1 //===- SemaChecking.cpp - Extra Semantic Checking -------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  This file implements extra semantic analysis beyond what is enforced
10 //  by the C type system.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/AST/APValue.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/Attr.h"
17 #include "clang/AST/AttrIterator.h"
18 #include "clang/AST/CharUnits.h"
19 #include "clang/AST/Decl.h"
20 #include "clang/AST/DeclBase.h"
21 #include "clang/AST/DeclCXX.h"
22 #include "clang/AST/DeclObjC.h"
23 #include "clang/AST/DeclarationName.h"
24 #include "clang/AST/EvaluatedExprVisitor.h"
25 #include "clang/AST/Expr.h"
26 #include "clang/AST/ExprCXX.h"
27 #include "clang/AST/ExprObjC.h"
28 #include "clang/AST/ExprOpenMP.h"
29 #include "clang/AST/FormatString.h"
30 #include "clang/AST/NSAPI.h"
31 #include "clang/AST/NonTrivialTypeVisitor.h"
32 #include "clang/AST/OperationKinds.h"
33 #include "clang/AST/RecordLayout.h"
34 #include "clang/AST/Stmt.h"
35 #include "clang/AST/TemplateBase.h"
36 #include "clang/AST/Type.h"
37 #include "clang/AST/TypeLoc.h"
38 #include "clang/AST/UnresolvedSet.h"
39 #include "clang/Basic/AddressSpaces.h"
40 #include "clang/Basic/CharInfo.h"
41 #include "clang/Basic/Diagnostic.h"
42 #include "clang/Basic/IdentifierTable.h"
43 #include "clang/Basic/LLVM.h"
44 #include "clang/Basic/LangOptions.h"
45 #include "clang/Basic/OpenCLOptions.h"
46 #include "clang/Basic/OperatorKinds.h"
47 #include "clang/Basic/PartialDiagnostic.h"
48 #include "clang/Basic/SourceLocation.h"
49 #include "clang/Basic/SourceManager.h"
50 #include "clang/Basic/Specifiers.h"
51 #include "clang/Basic/SyncScope.h"
52 #include "clang/Basic/TargetBuiltins.h"
53 #include "clang/Basic/TargetCXXABI.h"
54 #include "clang/Basic/TargetInfo.h"
55 #include "clang/Basic/TypeTraits.h"
56 #include "clang/Lex/Lexer.h" // TODO: Extract static functions to fix layering.
57 #include "clang/Sema/Initialization.h"
58 #include "clang/Sema/Lookup.h"
59 #include "clang/Sema/Ownership.h"
60 #include "clang/Sema/Scope.h"
61 #include "clang/Sema/ScopeInfo.h"
62 #include "clang/Sema/Sema.h"
63 #include "clang/Sema/SemaInternal.h"
64 #include "llvm/ADT/APFloat.h"
65 #include "llvm/ADT/APInt.h"
66 #include "llvm/ADT/APSInt.h"
67 #include "llvm/ADT/ArrayRef.h"
68 #include "llvm/ADT/DenseMap.h"
69 #include "llvm/ADT/FoldingSet.h"
70 #include "llvm/ADT/None.h"
71 #include "llvm/ADT/Optional.h"
72 #include "llvm/ADT/STLExtras.h"
73 #include "llvm/ADT/SmallBitVector.h"
74 #include "llvm/ADT/SmallPtrSet.h"
75 #include "llvm/ADT/SmallString.h"
76 #include "llvm/ADT/SmallVector.h"
77 #include "llvm/ADT/StringRef.h"
78 #include "llvm/ADT/StringSet.h"
79 #include "llvm/ADT/StringSwitch.h"
80 #include "llvm/ADT/Triple.h"
81 #include "llvm/Support/AtomicOrdering.h"
82 #include "llvm/Support/Casting.h"
83 #include "llvm/Support/Compiler.h"
84 #include "llvm/Support/ConvertUTF.h"
85 #include "llvm/Support/ErrorHandling.h"
86 #include "llvm/Support/Format.h"
87 #include "llvm/Support/Locale.h"
88 #include "llvm/Support/MathExtras.h"
89 #include "llvm/Support/SaveAndRestore.h"
90 #include "llvm/Support/raw_ostream.h"
91 #include <algorithm>
92 #include <bitset>
93 #include <cassert>
94 #include <cctype>
95 #include <cstddef>
96 #include <cstdint>
97 #include <functional>
98 #include <limits>
99 #include <string>
100 #include <tuple>
101 #include <utility>
102 
103 using namespace clang;
104 using namespace sema;
105 
106 SourceLocation Sema::getLocationOfStringLiteralByte(const StringLiteral *SL,
107                                                     unsigned ByteNo) const {
108   return SL->getLocationOfByte(ByteNo, getSourceManager(), LangOpts,
109                                Context.getTargetInfo());
110 }
111 
112 /// Checks that a call expression's argument count is the desired number.
113 /// This is useful when doing custom type-checking.  Returns true on error.
114 static bool checkArgCount(Sema &S, CallExpr *call, unsigned desiredArgCount) {
115   unsigned argCount = call->getNumArgs();
116   if (argCount == desiredArgCount) return false;
117 
118   if (argCount < desiredArgCount)
119     return S.Diag(call->getEndLoc(), diag::err_typecheck_call_too_few_args)
120            << 0 /*function call*/ << desiredArgCount << argCount
121            << call->getSourceRange();
122 
123   // Highlight all the excess arguments.
124   SourceRange range(call->getArg(desiredArgCount)->getBeginLoc(),
125                     call->getArg(argCount - 1)->getEndLoc());
126 
127   return S.Diag(range.getBegin(), diag::err_typecheck_call_too_many_args)
128     << 0 /*function call*/ << desiredArgCount << argCount
129     << call->getArg(1)->getSourceRange();
130 }
131 
132 /// Check that the first argument to __builtin_annotation is an integer
133 /// and the second argument is a non-wide string literal.
134 static bool SemaBuiltinAnnotation(Sema &S, CallExpr *TheCall) {
135   if (checkArgCount(S, TheCall, 2))
136     return true;
137 
138   // First argument should be an integer.
139   Expr *ValArg = TheCall->getArg(0);
140   QualType Ty = ValArg->getType();
141   if (!Ty->isIntegerType()) {
142     S.Diag(ValArg->getBeginLoc(), diag::err_builtin_annotation_first_arg)
143         << ValArg->getSourceRange();
144     return true;
145   }
146 
147   // Second argument should be a constant string.
148   Expr *StrArg = TheCall->getArg(1)->IgnoreParenCasts();
149   StringLiteral *Literal = dyn_cast<StringLiteral>(StrArg);
150   if (!Literal || !Literal->isAscii()) {
151     S.Diag(StrArg->getBeginLoc(), diag::err_builtin_annotation_second_arg)
152         << StrArg->getSourceRange();
153     return true;
154   }
155 
156   TheCall->setType(Ty);
157   return false;
158 }
159 
160 static bool SemaBuiltinMSVCAnnotation(Sema &S, CallExpr *TheCall) {
161   // We need at least one argument.
162   if (TheCall->getNumArgs() < 1) {
163     S.Diag(TheCall->getEndLoc(), diag::err_typecheck_call_too_few_args_at_least)
164         << 0 << 1 << TheCall->getNumArgs()
165         << TheCall->getCallee()->getSourceRange();
166     return true;
167   }
168 
169   // All arguments should be wide string literals.
170   for (Expr *Arg : TheCall->arguments()) {
171     auto *Literal = dyn_cast<StringLiteral>(Arg->IgnoreParenCasts());
172     if (!Literal || !Literal->isWide()) {
173       S.Diag(Arg->getBeginLoc(), diag::err_msvc_annotation_wide_str)
174           << Arg->getSourceRange();
175       return true;
176     }
177   }
178 
179   return false;
180 }
181 
182 /// Check that the argument to __builtin_addressof is a glvalue, and set the
183 /// result type to the corresponding pointer type.
184 static bool SemaBuiltinAddressof(Sema &S, CallExpr *TheCall) {
185   if (checkArgCount(S, TheCall, 1))
186     return true;
187 
188   ExprResult Arg(TheCall->getArg(0));
189   QualType ResultType = S.CheckAddressOfOperand(Arg, TheCall->getBeginLoc());
190   if (ResultType.isNull())
191     return true;
192 
193   TheCall->setArg(0, Arg.get());
194   TheCall->setType(ResultType);
195   return false;
196 }
197 
198 /// Check the number of arguments and set the result type to
199 /// the argument type.
200 static bool SemaBuiltinPreserveAI(Sema &S, CallExpr *TheCall) {
201   if (checkArgCount(S, TheCall, 1))
202     return true;
203 
204   TheCall->setType(TheCall->getArg(0)->getType());
205   return false;
206 }
207 
208 /// Check that the value argument for __builtin_is_aligned(value, alignment) and
209 /// __builtin_aligned_{up,down}(value, alignment) is an integer or a pointer
210 /// type (but not a function pointer) and that the alignment is a power-of-two.
211 static bool SemaBuiltinAlignment(Sema &S, CallExpr *TheCall, unsigned ID) {
212   if (checkArgCount(S, TheCall, 2))
213     return true;
214 
215   clang::Expr *Source = TheCall->getArg(0);
216   bool IsBooleanAlignBuiltin = ID == Builtin::BI__builtin_is_aligned;
217 
218   auto IsValidIntegerType = [](QualType Ty) {
219     return Ty->isIntegerType() && !Ty->isEnumeralType() && !Ty->isBooleanType();
220   };
221   QualType SrcTy = Source->getType();
222   // We should also be able to use it with arrays (but not functions!).
223   if (SrcTy->canDecayToPointerType() && SrcTy->isArrayType()) {
224     SrcTy = S.Context.getDecayedType(SrcTy);
225   }
226   if ((!SrcTy->isPointerType() && !IsValidIntegerType(SrcTy)) ||
227       SrcTy->isFunctionPointerType()) {
228     // FIXME: this is not quite the right error message since we don't allow
229     // floating point types, or member pointers.
230     S.Diag(Source->getExprLoc(), diag::err_typecheck_expect_scalar_operand)
231         << SrcTy;
232     return true;
233   }
234 
235   clang::Expr *AlignOp = TheCall->getArg(1);
236   if (!IsValidIntegerType(AlignOp->getType())) {
237     S.Diag(AlignOp->getExprLoc(), diag::err_typecheck_expect_int)
238         << AlignOp->getType();
239     return true;
240   }
241   Expr::EvalResult AlignResult;
242   unsigned MaxAlignmentBits = S.Context.getIntWidth(SrcTy) - 1;
243   // We can't check validity of alignment if it is value dependent.
244   if (!AlignOp->isValueDependent() &&
245       AlignOp->EvaluateAsInt(AlignResult, S.Context,
246                              Expr::SE_AllowSideEffects)) {
247     llvm::APSInt AlignValue = AlignResult.Val.getInt();
248     llvm::APSInt MaxValue(
249         llvm::APInt::getOneBitSet(MaxAlignmentBits + 1, MaxAlignmentBits));
250     if (AlignValue < 1) {
251       S.Diag(AlignOp->getExprLoc(), diag::err_alignment_too_small) << 1;
252       return true;
253     }
254     if (llvm::APSInt::compareValues(AlignValue, MaxValue) > 0) {
255       S.Diag(AlignOp->getExprLoc(), diag::err_alignment_too_big)
256           << toString(MaxValue, 10);
257       return true;
258     }
259     if (!AlignValue.isPowerOf2()) {
260       S.Diag(AlignOp->getExprLoc(), diag::err_alignment_not_power_of_two);
261       return true;
262     }
263     if (AlignValue == 1) {
264       S.Diag(AlignOp->getExprLoc(), diag::warn_alignment_builtin_useless)
265           << IsBooleanAlignBuiltin;
266     }
267   }
268 
269   ExprResult SrcArg = S.PerformCopyInitialization(
270       InitializedEntity::InitializeParameter(S.Context, SrcTy, false),
271       SourceLocation(), Source);
272   if (SrcArg.isInvalid())
273     return true;
274   TheCall->setArg(0, SrcArg.get());
275   ExprResult AlignArg =
276       S.PerformCopyInitialization(InitializedEntity::InitializeParameter(
277                                       S.Context, AlignOp->getType(), false),
278                                   SourceLocation(), AlignOp);
279   if (AlignArg.isInvalid())
280     return true;
281   TheCall->setArg(1, AlignArg.get());
282   // For align_up/align_down, the return type is the same as the (potentially
283   // decayed) argument type including qualifiers. For is_aligned(), the result
284   // is always bool.
285   TheCall->setType(IsBooleanAlignBuiltin ? S.Context.BoolTy : SrcTy);
286   return false;
287 }
288 
289 static bool SemaBuiltinOverflow(Sema &S, CallExpr *TheCall,
290                                 unsigned BuiltinID) {
291   if (checkArgCount(S, TheCall, 3))
292     return true;
293 
294   // First two arguments should be integers.
295   for (unsigned I = 0; I < 2; ++I) {
296     ExprResult Arg = S.DefaultFunctionArrayLvalueConversion(TheCall->getArg(I));
297     if (Arg.isInvalid()) return true;
298     TheCall->setArg(I, Arg.get());
299 
300     QualType Ty = Arg.get()->getType();
301     if (!Ty->isIntegerType()) {
302       S.Diag(Arg.get()->getBeginLoc(), diag::err_overflow_builtin_must_be_int)
303           << Ty << Arg.get()->getSourceRange();
304       return true;
305     }
306   }
307 
308   // Third argument should be a pointer to a non-const integer.
309   // IRGen correctly handles volatile, restrict, and address spaces, and
310   // the other qualifiers aren't possible.
311   {
312     ExprResult Arg = S.DefaultFunctionArrayLvalueConversion(TheCall->getArg(2));
313     if (Arg.isInvalid()) return true;
314     TheCall->setArg(2, Arg.get());
315 
316     QualType Ty = Arg.get()->getType();
317     const auto *PtrTy = Ty->getAs<PointerType>();
318     if (!PtrTy ||
319         !PtrTy->getPointeeType()->isIntegerType() ||
320         PtrTy->getPointeeType().isConstQualified()) {
321       S.Diag(Arg.get()->getBeginLoc(),
322              diag::err_overflow_builtin_must_be_ptr_int)
323         << Ty << Arg.get()->getSourceRange();
324       return true;
325     }
326   }
327 
328   // Disallow signed ExtIntType args larger than 128 bits to mul function until
329   // we improve backend support.
330   if (BuiltinID == Builtin::BI__builtin_mul_overflow) {
331     for (unsigned I = 0; I < 3; ++I) {
332       const auto Arg = TheCall->getArg(I);
333       // Third argument will be a pointer.
334       auto Ty = I < 2 ? Arg->getType() : Arg->getType()->getPointeeType();
335       if (Ty->isExtIntType() && Ty->isSignedIntegerType() &&
336           S.getASTContext().getIntWidth(Ty) > 128)
337         return S.Diag(Arg->getBeginLoc(),
338                       diag::err_overflow_builtin_ext_int_max_size)
339                << 128;
340     }
341   }
342 
343   return false;
344 }
345 
346 static bool SemaBuiltinCallWithStaticChain(Sema &S, CallExpr *BuiltinCall) {
347   if (checkArgCount(S, BuiltinCall, 2))
348     return true;
349 
350   SourceLocation BuiltinLoc = BuiltinCall->getBeginLoc();
351   Expr *Builtin = BuiltinCall->getCallee()->IgnoreImpCasts();
352   Expr *Call = BuiltinCall->getArg(0);
353   Expr *Chain = BuiltinCall->getArg(1);
354 
355   if (Call->getStmtClass() != Stmt::CallExprClass) {
356     S.Diag(BuiltinLoc, diag::err_first_argument_to_cwsc_not_call)
357         << Call->getSourceRange();
358     return true;
359   }
360 
361   auto CE = cast<CallExpr>(Call);
362   if (CE->getCallee()->getType()->isBlockPointerType()) {
363     S.Diag(BuiltinLoc, diag::err_first_argument_to_cwsc_block_call)
364         << Call->getSourceRange();
365     return true;
366   }
367 
368   const Decl *TargetDecl = CE->getCalleeDecl();
369   if (const FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(TargetDecl))
370     if (FD->getBuiltinID()) {
371       S.Diag(BuiltinLoc, diag::err_first_argument_to_cwsc_builtin_call)
372           << Call->getSourceRange();
373       return true;
374     }
375 
376   if (isa<CXXPseudoDestructorExpr>(CE->getCallee()->IgnoreParens())) {
377     S.Diag(BuiltinLoc, diag::err_first_argument_to_cwsc_pdtor_call)
378         << Call->getSourceRange();
379     return true;
380   }
381 
382   ExprResult ChainResult = S.UsualUnaryConversions(Chain);
383   if (ChainResult.isInvalid())
384     return true;
385   if (!ChainResult.get()->getType()->isPointerType()) {
386     S.Diag(BuiltinLoc, diag::err_second_argument_to_cwsc_not_pointer)
387         << Chain->getSourceRange();
388     return true;
389   }
390 
391   QualType ReturnTy = CE->getCallReturnType(S.Context);
392   QualType ArgTys[2] = { ReturnTy, ChainResult.get()->getType() };
393   QualType BuiltinTy = S.Context.getFunctionType(
394       ReturnTy, ArgTys, FunctionProtoType::ExtProtoInfo());
395   QualType BuiltinPtrTy = S.Context.getPointerType(BuiltinTy);
396 
397   Builtin =
398       S.ImpCastExprToType(Builtin, BuiltinPtrTy, CK_BuiltinFnToFnPtr).get();
399 
400   BuiltinCall->setType(CE->getType());
401   BuiltinCall->setValueKind(CE->getValueKind());
402   BuiltinCall->setObjectKind(CE->getObjectKind());
403   BuiltinCall->setCallee(Builtin);
404   BuiltinCall->setArg(1, ChainResult.get());
405 
406   return false;
407 }
408 
409 namespace {
410 
411 class EstimateSizeFormatHandler
412     : public analyze_format_string::FormatStringHandler {
413   size_t Size;
414 
415 public:
416   EstimateSizeFormatHandler(StringRef Format)
417       : Size(std::min(Format.find(0), Format.size()) +
418              1 /* null byte always written by sprintf */) {}
419 
420   bool HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier &FS,
421                              const char *, unsigned SpecifierLen) override {
422 
423     const size_t FieldWidth = computeFieldWidth(FS);
424     const size_t Precision = computePrecision(FS);
425 
426     // The actual format.
427     switch (FS.getConversionSpecifier().getKind()) {
428     // Just a char.
429     case analyze_format_string::ConversionSpecifier::cArg:
430     case analyze_format_string::ConversionSpecifier::CArg:
431       Size += std::max(FieldWidth, (size_t)1);
432       break;
433     // Just an integer.
434     case analyze_format_string::ConversionSpecifier::dArg:
435     case analyze_format_string::ConversionSpecifier::DArg:
436     case analyze_format_string::ConversionSpecifier::iArg:
437     case analyze_format_string::ConversionSpecifier::oArg:
438     case analyze_format_string::ConversionSpecifier::OArg:
439     case analyze_format_string::ConversionSpecifier::uArg:
440     case analyze_format_string::ConversionSpecifier::UArg:
441     case analyze_format_string::ConversionSpecifier::xArg:
442     case analyze_format_string::ConversionSpecifier::XArg:
443       Size += std::max(FieldWidth, Precision);
444       break;
445 
446     // %g style conversion switches between %f or %e style dynamically.
447     // %f always takes less space, so default to it.
448     case analyze_format_string::ConversionSpecifier::gArg:
449     case analyze_format_string::ConversionSpecifier::GArg:
450 
451     // Floating point number in the form '[+]ddd.ddd'.
452     case analyze_format_string::ConversionSpecifier::fArg:
453     case analyze_format_string::ConversionSpecifier::FArg:
454       Size += std::max(FieldWidth, 1 /* integer part */ +
455                                        (Precision ? 1 + Precision
456                                                   : 0) /* period + decimal */);
457       break;
458 
459     // Floating point number in the form '[-]d.ddde[+-]dd'.
460     case analyze_format_string::ConversionSpecifier::eArg:
461     case analyze_format_string::ConversionSpecifier::EArg:
462       Size +=
463           std::max(FieldWidth,
464                    1 /* integer part */ +
465                        (Precision ? 1 + Precision : 0) /* period + decimal */ +
466                        1 /* e or E letter */ + 2 /* exponent */);
467       break;
468 
469     // Floating point number in the form '[-]0xh.hhhhp±dd'.
470     case analyze_format_string::ConversionSpecifier::aArg:
471     case analyze_format_string::ConversionSpecifier::AArg:
472       Size +=
473           std::max(FieldWidth,
474                    2 /* 0x */ + 1 /* integer part */ +
475                        (Precision ? 1 + Precision : 0) /* period + decimal */ +
476                        1 /* p or P letter */ + 1 /* + or - */ + 1 /* value */);
477       break;
478 
479     // Just a string.
480     case analyze_format_string::ConversionSpecifier::sArg:
481     case analyze_format_string::ConversionSpecifier::SArg:
482       Size += FieldWidth;
483       break;
484 
485     // Just a pointer in the form '0xddd'.
486     case analyze_format_string::ConversionSpecifier::pArg:
487       Size += std::max(FieldWidth, 2 /* leading 0x */ + Precision);
488       break;
489 
490     // A plain percent.
491     case analyze_format_string::ConversionSpecifier::PercentArg:
492       Size += 1;
493       break;
494 
495     default:
496       break;
497     }
498 
499     Size += FS.hasPlusPrefix() || FS.hasSpacePrefix();
500 
501     if (FS.hasAlternativeForm()) {
502       switch (FS.getConversionSpecifier().getKind()) {
503       default:
504         break;
505       // Force a leading '0'.
506       case analyze_format_string::ConversionSpecifier::oArg:
507         Size += 1;
508         break;
509       // Force a leading '0x'.
510       case analyze_format_string::ConversionSpecifier::xArg:
511       case analyze_format_string::ConversionSpecifier::XArg:
512         Size += 2;
513         break;
514       // Force a period '.' before decimal, even if precision is 0.
515       case analyze_format_string::ConversionSpecifier::aArg:
516       case analyze_format_string::ConversionSpecifier::AArg:
517       case analyze_format_string::ConversionSpecifier::eArg:
518       case analyze_format_string::ConversionSpecifier::EArg:
519       case analyze_format_string::ConversionSpecifier::fArg:
520       case analyze_format_string::ConversionSpecifier::FArg:
521       case analyze_format_string::ConversionSpecifier::gArg:
522       case analyze_format_string::ConversionSpecifier::GArg:
523         Size += (Precision ? 0 : 1);
524         break;
525       }
526     }
527     assert(SpecifierLen <= Size && "no underflow");
528     Size -= SpecifierLen;
529     return true;
530   }
531 
532   size_t getSizeLowerBound() const { return Size; }
533 
534 private:
535   static size_t computeFieldWidth(const analyze_printf::PrintfSpecifier &FS) {
536     const analyze_format_string::OptionalAmount &FW = FS.getFieldWidth();
537     size_t FieldWidth = 0;
538     if (FW.getHowSpecified() == analyze_format_string::OptionalAmount::Constant)
539       FieldWidth = FW.getConstantAmount();
540     return FieldWidth;
541   }
542 
543   static size_t computePrecision(const analyze_printf::PrintfSpecifier &FS) {
544     const analyze_format_string::OptionalAmount &FW = FS.getPrecision();
545     size_t Precision = 0;
546 
547     // See man 3 printf for default precision value based on the specifier.
548     switch (FW.getHowSpecified()) {
549     case analyze_format_string::OptionalAmount::NotSpecified:
550       switch (FS.getConversionSpecifier().getKind()) {
551       default:
552         break;
553       case analyze_format_string::ConversionSpecifier::dArg: // %d
554       case analyze_format_string::ConversionSpecifier::DArg: // %D
555       case analyze_format_string::ConversionSpecifier::iArg: // %i
556         Precision = 1;
557         break;
558       case analyze_format_string::ConversionSpecifier::oArg: // %d
559       case analyze_format_string::ConversionSpecifier::OArg: // %D
560       case analyze_format_string::ConversionSpecifier::uArg: // %d
561       case analyze_format_string::ConversionSpecifier::UArg: // %D
562       case analyze_format_string::ConversionSpecifier::xArg: // %d
563       case analyze_format_string::ConversionSpecifier::XArg: // %D
564         Precision = 1;
565         break;
566       case analyze_format_string::ConversionSpecifier::fArg: // %f
567       case analyze_format_string::ConversionSpecifier::FArg: // %F
568       case analyze_format_string::ConversionSpecifier::eArg: // %e
569       case analyze_format_string::ConversionSpecifier::EArg: // %E
570       case analyze_format_string::ConversionSpecifier::gArg: // %g
571       case analyze_format_string::ConversionSpecifier::GArg: // %G
572         Precision = 6;
573         break;
574       case analyze_format_string::ConversionSpecifier::pArg: // %d
575         Precision = 1;
576         break;
577       }
578       break;
579     case analyze_format_string::OptionalAmount::Constant:
580       Precision = FW.getConstantAmount();
581       break;
582     default:
583       break;
584     }
585     return Precision;
586   }
587 };
588 
589 } // namespace
590 
591 void Sema::checkFortifiedBuiltinMemoryFunction(FunctionDecl *FD,
592                                                CallExpr *TheCall) {
593   if (TheCall->isValueDependent() || TheCall->isTypeDependent() ||
594       isConstantEvaluated())
595     return;
596 
597   unsigned BuiltinID = FD->getBuiltinID(/*ConsiderWrappers=*/true);
598   if (!BuiltinID)
599     return;
600 
601   const TargetInfo &TI = getASTContext().getTargetInfo();
602   unsigned SizeTypeWidth = TI.getTypeWidth(TI.getSizeType());
603 
604   auto ComputeExplicitObjectSizeArgument =
605       [&](unsigned Index) -> Optional<llvm::APSInt> {
606     Expr::EvalResult Result;
607     Expr *SizeArg = TheCall->getArg(Index);
608     if (!SizeArg->EvaluateAsInt(Result, getASTContext()))
609       return llvm::None;
610     return Result.Val.getInt();
611   };
612 
613   auto ComputeSizeArgument = [&](unsigned Index) -> Optional<llvm::APSInt> {
614     // If the parameter has a pass_object_size attribute, then we should use its
615     // (potentially) more strict checking mode. Otherwise, conservatively assume
616     // type 0.
617     int BOSType = 0;
618     if (const auto *POS =
619             FD->getParamDecl(Index)->getAttr<PassObjectSizeAttr>())
620       BOSType = POS->getType();
621 
622     const Expr *ObjArg = TheCall->getArg(Index);
623     uint64_t Result;
624     if (!ObjArg->tryEvaluateObjectSize(Result, getASTContext(), BOSType))
625       return llvm::None;
626 
627     // Get the object size in the target's size_t width.
628     return llvm::APSInt::getUnsigned(Result).extOrTrunc(SizeTypeWidth);
629   };
630 
631   auto ComputeStrLenArgument = [&](unsigned Index) -> Optional<llvm::APSInt> {
632     Expr *ObjArg = TheCall->getArg(Index);
633     uint64_t Result;
634     if (!ObjArg->tryEvaluateStrLen(Result, getASTContext()))
635       return llvm::None;
636     // Add 1 for null byte.
637     return llvm::APSInt::getUnsigned(Result + 1).extOrTrunc(SizeTypeWidth);
638   };
639 
640   Optional<llvm::APSInt> SourceSize;
641   Optional<llvm::APSInt> DestinationSize;
642   unsigned DiagID = 0;
643   bool IsChkVariant = false;
644 
645   switch (BuiltinID) {
646   default:
647     return;
648   case Builtin::BI__builtin_strcpy:
649   case Builtin::BIstrcpy: {
650     DiagID = diag::warn_fortify_strlen_overflow;
651     SourceSize = ComputeStrLenArgument(1);
652     DestinationSize = ComputeSizeArgument(0);
653     break;
654   }
655 
656   case Builtin::BI__builtin___strcpy_chk: {
657     DiagID = diag::warn_fortify_strlen_overflow;
658     SourceSize = ComputeStrLenArgument(1);
659     DestinationSize = ComputeExplicitObjectSizeArgument(2);
660     IsChkVariant = true;
661     break;
662   }
663 
664   case Builtin::BIsprintf:
665   case Builtin::BI__builtin___sprintf_chk: {
666     size_t FormatIndex = BuiltinID == Builtin::BIsprintf ? 1 : 3;
667     auto *FormatExpr = TheCall->getArg(FormatIndex)->IgnoreParenImpCasts();
668 
669     if (auto *Format = dyn_cast<StringLiteral>(FormatExpr)) {
670 
671       if (!Format->isAscii() && !Format->isUTF8())
672         return;
673 
674       StringRef FormatStrRef = Format->getString();
675       EstimateSizeFormatHandler H(FormatStrRef);
676       const char *FormatBytes = FormatStrRef.data();
677       const ConstantArrayType *T =
678           Context.getAsConstantArrayType(Format->getType());
679       assert(T && "String literal not of constant array type!");
680       size_t TypeSize = T->getSize().getZExtValue();
681 
682       // In case there's a null byte somewhere.
683       size_t StrLen =
684           std::min(std::max(TypeSize, size_t(1)) - 1, FormatStrRef.find(0));
685       if (!analyze_format_string::ParsePrintfString(
686               H, FormatBytes, FormatBytes + StrLen, getLangOpts(),
687               Context.getTargetInfo(), false)) {
688         DiagID = diag::warn_fortify_source_format_overflow;
689         SourceSize = llvm::APSInt::getUnsigned(H.getSizeLowerBound())
690                          .extOrTrunc(SizeTypeWidth);
691         if (BuiltinID == Builtin::BI__builtin___sprintf_chk) {
692           DestinationSize = ComputeExplicitObjectSizeArgument(2);
693           IsChkVariant = true;
694         } else {
695           DestinationSize = ComputeSizeArgument(0);
696         }
697         break;
698       }
699     }
700     return;
701   }
702   case Builtin::BI__builtin___memcpy_chk:
703   case Builtin::BI__builtin___memmove_chk:
704   case Builtin::BI__builtin___memset_chk:
705   case Builtin::BI__builtin___strlcat_chk:
706   case Builtin::BI__builtin___strlcpy_chk:
707   case Builtin::BI__builtin___strncat_chk:
708   case Builtin::BI__builtin___strncpy_chk:
709   case Builtin::BI__builtin___stpncpy_chk:
710   case Builtin::BI__builtin___memccpy_chk:
711   case Builtin::BI__builtin___mempcpy_chk: {
712     DiagID = diag::warn_builtin_chk_overflow;
713     SourceSize = ComputeExplicitObjectSizeArgument(TheCall->getNumArgs() - 2);
714     DestinationSize =
715         ComputeExplicitObjectSizeArgument(TheCall->getNumArgs() - 1);
716     IsChkVariant = true;
717     break;
718   }
719 
720   case Builtin::BI__builtin___snprintf_chk:
721   case Builtin::BI__builtin___vsnprintf_chk: {
722     DiagID = diag::warn_builtin_chk_overflow;
723     SourceSize = ComputeExplicitObjectSizeArgument(1);
724     DestinationSize = ComputeExplicitObjectSizeArgument(3);
725     IsChkVariant = true;
726     break;
727   }
728 
729   case Builtin::BIstrncat:
730   case Builtin::BI__builtin_strncat:
731   case Builtin::BIstrncpy:
732   case Builtin::BI__builtin_strncpy:
733   case Builtin::BIstpncpy:
734   case Builtin::BI__builtin_stpncpy: {
735     // Whether these functions overflow depends on the runtime strlen of the
736     // string, not just the buffer size, so emitting the "always overflow"
737     // diagnostic isn't quite right. We should still diagnose passing a buffer
738     // size larger than the destination buffer though; this is a runtime abort
739     // in _FORTIFY_SOURCE mode, and is quite suspicious otherwise.
740     DiagID = diag::warn_fortify_source_size_mismatch;
741     SourceSize = ComputeExplicitObjectSizeArgument(TheCall->getNumArgs() - 1);
742     DestinationSize = ComputeSizeArgument(0);
743     break;
744   }
745 
746   case Builtin::BImemcpy:
747   case Builtin::BI__builtin_memcpy:
748   case Builtin::BImemmove:
749   case Builtin::BI__builtin_memmove:
750   case Builtin::BImemset:
751   case Builtin::BI__builtin_memset:
752   case Builtin::BImempcpy:
753   case Builtin::BI__builtin_mempcpy: {
754     DiagID = diag::warn_fortify_source_overflow;
755     SourceSize = ComputeExplicitObjectSizeArgument(TheCall->getNumArgs() - 1);
756     DestinationSize = ComputeSizeArgument(0);
757     break;
758   }
759   case Builtin::BIsnprintf:
760   case Builtin::BI__builtin_snprintf:
761   case Builtin::BIvsnprintf:
762   case Builtin::BI__builtin_vsnprintf: {
763     DiagID = diag::warn_fortify_source_size_mismatch;
764     SourceSize = ComputeExplicitObjectSizeArgument(1);
765     DestinationSize = ComputeSizeArgument(0);
766     break;
767   }
768   }
769 
770   if (!SourceSize || !DestinationSize ||
771       SourceSize.getValue().ule(DestinationSize.getValue()))
772     return;
773 
774   StringRef FunctionName = getASTContext().BuiltinInfo.getName(BuiltinID);
775   // Skim off the details of whichever builtin was called to produce a better
776   // diagnostic, as it's unlikley that the user wrote the __builtin explicitly.
777   if (IsChkVariant) {
778     FunctionName = FunctionName.drop_front(std::strlen("__builtin___"));
779     FunctionName = FunctionName.drop_back(std::strlen("_chk"));
780   } else if (FunctionName.startswith("__builtin_")) {
781     FunctionName = FunctionName.drop_front(std::strlen("__builtin_"));
782   }
783 
784   SmallString<16> DestinationStr;
785   SmallString<16> SourceStr;
786   DestinationSize->toString(DestinationStr, /*Radix=*/10);
787   SourceSize->toString(SourceStr, /*Radix=*/10);
788   DiagRuntimeBehavior(TheCall->getBeginLoc(), TheCall,
789                       PDiag(DiagID)
790                           << FunctionName << DestinationStr << SourceStr);
791 }
792 
793 static bool SemaBuiltinSEHScopeCheck(Sema &SemaRef, CallExpr *TheCall,
794                                      Scope::ScopeFlags NeededScopeFlags,
795                                      unsigned DiagID) {
796   // Scopes aren't available during instantiation. Fortunately, builtin
797   // functions cannot be template args so they cannot be formed through template
798   // instantiation. Therefore checking once during the parse is sufficient.
799   if (SemaRef.inTemplateInstantiation())
800     return false;
801 
802   Scope *S = SemaRef.getCurScope();
803   while (S && !S->isSEHExceptScope())
804     S = S->getParent();
805   if (!S || !(S->getFlags() & NeededScopeFlags)) {
806     auto *DRE = cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts());
807     SemaRef.Diag(TheCall->getExprLoc(), DiagID)
808         << DRE->getDecl()->getIdentifier();
809     return true;
810   }
811 
812   return false;
813 }
814 
815 static inline bool isBlockPointer(Expr *Arg) {
816   return Arg->getType()->isBlockPointerType();
817 }
818 
819 /// OpenCL C v2.0, s6.13.17.2 - Checks that the block parameters are all local
820 /// void*, which is a requirement of device side enqueue.
821 static bool checkOpenCLBlockArgs(Sema &S, Expr *BlockArg) {
822   const BlockPointerType *BPT =
823       cast<BlockPointerType>(BlockArg->getType().getCanonicalType());
824   ArrayRef<QualType> Params =
825       BPT->getPointeeType()->castAs<FunctionProtoType>()->getParamTypes();
826   unsigned ArgCounter = 0;
827   bool IllegalParams = false;
828   // Iterate through the block parameters until either one is found that is not
829   // a local void*, or the block is valid.
830   for (ArrayRef<QualType>::iterator I = Params.begin(), E = Params.end();
831        I != E; ++I, ++ArgCounter) {
832     if (!(*I)->isPointerType() || !(*I)->getPointeeType()->isVoidType() ||
833         (*I)->getPointeeType().getQualifiers().getAddressSpace() !=
834             LangAS::opencl_local) {
835       // Get the location of the error. If a block literal has been passed
836       // (BlockExpr) then we can point straight to the offending argument,
837       // else we just point to the variable reference.
838       SourceLocation ErrorLoc;
839       if (isa<BlockExpr>(BlockArg)) {
840         BlockDecl *BD = cast<BlockExpr>(BlockArg)->getBlockDecl();
841         ErrorLoc = BD->getParamDecl(ArgCounter)->getBeginLoc();
842       } else if (isa<DeclRefExpr>(BlockArg)) {
843         ErrorLoc = cast<DeclRefExpr>(BlockArg)->getBeginLoc();
844       }
845       S.Diag(ErrorLoc,
846              diag::err_opencl_enqueue_kernel_blocks_non_local_void_args);
847       IllegalParams = true;
848     }
849   }
850 
851   return IllegalParams;
852 }
853 
854 static bool checkOpenCLSubgroupExt(Sema &S, CallExpr *Call) {
855   if (!S.getOpenCLOptions().isSupported("cl_khr_subgroups", S.getLangOpts())) {
856     S.Diag(Call->getBeginLoc(), diag::err_opencl_requires_extension)
857         << 1 << Call->getDirectCallee() << "cl_khr_subgroups";
858     return true;
859   }
860   return false;
861 }
862 
863 static bool SemaOpenCLBuiltinNDRangeAndBlock(Sema &S, CallExpr *TheCall) {
864   if (checkArgCount(S, TheCall, 2))
865     return true;
866 
867   if (checkOpenCLSubgroupExt(S, TheCall))
868     return true;
869 
870   // First argument is an ndrange_t type.
871   Expr *NDRangeArg = TheCall->getArg(0);
872   if (NDRangeArg->getType().getUnqualifiedType().getAsString() != "ndrange_t") {
873     S.Diag(NDRangeArg->getBeginLoc(), diag::err_opencl_builtin_expected_type)
874         << TheCall->getDirectCallee() << "'ndrange_t'";
875     return true;
876   }
877 
878   Expr *BlockArg = TheCall->getArg(1);
879   if (!isBlockPointer(BlockArg)) {
880     S.Diag(BlockArg->getBeginLoc(), diag::err_opencl_builtin_expected_type)
881         << TheCall->getDirectCallee() << "block";
882     return true;
883   }
884   return checkOpenCLBlockArgs(S, BlockArg);
885 }
886 
887 /// OpenCL C v2.0, s6.13.17.6 - Check the argument to the
888 /// get_kernel_work_group_size
889 /// and get_kernel_preferred_work_group_size_multiple builtin functions.
890 static bool SemaOpenCLBuiltinKernelWorkGroupSize(Sema &S, CallExpr *TheCall) {
891   if (checkArgCount(S, TheCall, 1))
892     return true;
893 
894   Expr *BlockArg = TheCall->getArg(0);
895   if (!isBlockPointer(BlockArg)) {
896     S.Diag(BlockArg->getBeginLoc(), diag::err_opencl_builtin_expected_type)
897         << TheCall->getDirectCallee() << "block";
898     return true;
899   }
900   return checkOpenCLBlockArgs(S, BlockArg);
901 }
902 
903 /// Diagnose integer type and any valid implicit conversion to it.
904 static bool checkOpenCLEnqueueIntType(Sema &S, Expr *E,
905                                       const QualType &IntType);
906 
907 static bool checkOpenCLEnqueueLocalSizeArgs(Sema &S, CallExpr *TheCall,
908                                             unsigned Start, unsigned End) {
909   bool IllegalParams = false;
910   for (unsigned I = Start; I <= End; ++I)
911     IllegalParams |= checkOpenCLEnqueueIntType(S, TheCall->getArg(I),
912                                               S.Context.getSizeType());
913   return IllegalParams;
914 }
915 
916 /// OpenCL v2.0, s6.13.17.1 - Check that sizes are provided for all
917 /// 'local void*' parameter of passed block.
918 static bool checkOpenCLEnqueueVariadicArgs(Sema &S, CallExpr *TheCall,
919                                            Expr *BlockArg,
920                                            unsigned NumNonVarArgs) {
921   const BlockPointerType *BPT =
922       cast<BlockPointerType>(BlockArg->getType().getCanonicalType());
923   unsigned NumBlockParams =
924       BPT->getPointeeType()->castAs<FunctionProtoType>()->getNumParams();
925   unsigned TotalNumArgs = TheCall->getNumArgs();
926 
927   // For each argument passed to the block, a corresponding uint needs to
928   // be passed to describe the size of the local memory.
929   if (TotalNumArgs != NumBlockParams + NumNonVarArgs) {
930     S.Diag(TheCall->getBeginLoc(),
931            diag::err_opencl_enqueue_kernel_local_size_args);
932     return true;
933   }
934 
935   // Check that the sizes of the local memory are specified by integers.
936   return checkOpenCLEnqueueLocalSizeArgs(S, TheCall, NumNonVarArgs,
937                                          TotalNumArgs - 1);
938 }
939 
940 /// OpenCL C v2.0, s6.13.17 - Enqueue kernel function contains four different
941 /// overload formats specified in Table 6.13.17.1.
942 /// int enqueue_kernel(queue_t queue,
943 ///                    kernel_enqueue_flags_t flags,
944 ///                    const ndrange_t ndrange,
945 ///                    void (^block)(void))
946 /// int enqueue_kernel(queue_t queue,
947 ///                    kernel_enqueue_flags_t flags,
948 ///                    const ndrange_t ndrange,
949 ///                    uint num_events_in_wait_list,
950 ///                    clk_event_t *event_wait_list,
951 ///                    clk_event_t *event_ret,
952 ///                    void (^block)(void))
953 /// int enqueue_kernel(queue_t queue,
954 ///                    kernel_enqueue_flags_t flags,
955 ///                    const ndrange_t ndrange,
956 ///                    void (^block)(local void*, ...),
957 ///                    uint size0, ...)
958 /// int enqueue_kernel(queue_t queue,
959 ///                    kernel_enqueue_flags_t flags,
960 ///                    const ndrange_t ndrange,
961 ///                    uint num_events_in_wait_list,
962 ///                    clk_event_t *event_wait_list,
963 ///                    clk_event_t *event_ret,
964 ///                    void (^block)(local void*, ...),
965 ///                    uint size0, ...)
966 static bool SemaOpenCLBuiltinEnqueueKernel(Sema &S, CallExpr *TheCall) {
967   unsigned NumArgs = TheCall->getNumArgs();
968 
969   if (NumArgs < 4) {
970     S.Diag(TheCall->getBeginLoc(),
971            diag::err_typecheck_call_too_few_args_at_least)
972         << 0 << 4 << NumArgs;
973     return true;
974   }
975 
976   Expr *Arg0 = TheCall->getArg(0);
977   Expr *Arg1 = TheCall->getArg(1);
978   Expr *Arg2 = TheCall->getArg(2);
979   Expr *Arg3 = TheCall->getArg(3);
980 
981   // First argument always needs to be a queue_t type.
982   if (!Arg0->getType()->isQueueT()) {
983     S.Diag(TheCall->getArg(0)->getBeginLoc(),
984            diag::err_opencl_builtin_expected_type)
985         << TheCall->getDirectCallee() << S.Context.OCLQueueTy;
986     return true;
987   }
988 
989   // Second argument always needs to be a kernel_enqueue_flags_t enum value.
990   if (!Arg1->getType()->isIntegerType()) {
991     S.Diag(TheCall->getArg(1)->getBeginLoc(),
992            diag::err_opencl_builtin_expected_type)
993         << TheCall->getDirectCallee() << "'kernel_enqueue_flags_t' (i.e. uint)";
994     return true;
995   }
996 
997   // Third argument is always an ndrange_t type.
998   if (Arg2->getType().getUnqualifiedType().getAsString() != "ndrange_t") {
999     S.Diag(TheCall->getArg(2)->getBeginLoc(),
1000            diag::err_opencl_builtin_expected_type)
1001         << TheCall->getDirectCallee() << "'ndrange_t'";
1002     return true;
1003   }
1004 
1005   // With four arguments, there is only one form that the function could be
1006   // called in: no events and no variable arguments.
1007   if (NumArgs == 4) {
1008     // check that the last argument is the right block type.
1009     if (!isBlockPointer(Arg3)) {
1010       S.Diag(Arg3->getBeginLoc(), diag::err_opencl_builtin_expected_type)
1011           << TheCall->getDirectCallee() << "block";
1012       return true;
1013     }
1014     // we have a block type, check the prototype
1015     const BlockPointerType *BPT =
1016         cast<BlockPointerType>(Arg3->getType().getCanonicalType());
1017     if (BPT->getPointeeType()->castAs<FunctionProtoType>()->getNumParams() > 0) {
1018       S.Diag(Arg3->getBeginLoc(),
1019              diag::err_opencl_enqueue_kernel_blocks_no_args);
1020       return true;
1021     }
1022     return false;
1023   }
1024   // we can have block + varargs.
1025   if (isBlockPointer(Arg3))
1026     return (checkOpenCLBlockArgs(S, Arg3) ||
1027             checkOpenCLEnqueueVariadicArgs(S, TheCall, Arg3, 4));
1028   // last two cases with either exactly 7 args or 7 args and varargs.
1029   if (NumArgs >= 7) {
1030     // check common block argument.
1031     Expr *Arg6 = TheCall->getArg(6);
1032     if (!isBlockPointer(Arg6)) {
1033       S.Diag(Arg6->getBeginLoc(), diag::err_opencl_builtin_expected_type)
1034           << TheCall->getDirectCallee() << "block";
1035       return true;
1036     }
1037     if (checkOpenCLBlockArgs(S, Arg6))
1038       return true;
1039 
1040     // Forth argument has to be any integer type.
1041     if (!Arg3->getType()->isIntegerType()) {
1042       S.Diag(TheCall->getArg(3)->getBeginLoc(),
1043              diag::err_opencl_builtin_expected_type)
1044           << TheCall->getDirectCallee() << "integer";
1045       return true;
1046     }
1047     // check remaining common arguments.
1048     Expr *Arg4 = TheCall->getArg(4);
1049     Expr *Arg5 = TheCall->getArg(5);
1050 
1051     // Fifth argument is always passed as a pointer to clk_event_t.
1052     if (!Arg4->isNullPointerConstant(S.Context,
1053                                      Expr::NPC_ValueDependentIsNotNull) &&
1054         !Arg4->getType()->getPointeeOrArrayElementType()->isClkEventT()) {
1055       S.Diag(TheCall->getArg(4)->getBeginLoc(),
1056              diag::err_opencl_builtin_expected_type)
1057           << TheCall->getDirectCallee()
1058           << S.Context.getPointerType(S.Context.OCLClkEventTy);
1059       return true;
1060     }
1061 
1062     // Sixth argument is always passed as a pointer to clk_event_t.
1063     if (!Arg5->isNullPointerConstant(S.Context,
1064                                      Expr::NPC_ValueDependentIsNotNull) &&
1065         !(Arg5->getType()->isPointerType() &&
1066           Arg5->getType()->getPointeeType()->isClkEventT())) {
1067       S.Diag(TheCall->getArg(5)->getBeginLoc(),
1068              diag::err_opencl_builtin_expected_type)
1069           << TheCall->getDirectCallee()
1070           << S.Context.getPointerType(S.Context.OCLClkEventTy);
1071       return true;
1072     }
1073 
1074     if (NumArgs == 7)
1075       return false;
1076 
1077     return checkOpenCLEnqueueVariadicArgs(S, TheCall, Arg6, 7);
1078   }
1079 
1080   // None of the specific case has been detected, give generic error
1081   S.Diag(TheCall->getBeginLoc(),
1082          diag::err_opencl_enqueue_kernel_incorrect_args);
1083   return true;
1084 }
1085 
1086 /// Returns OpenCL access qual.
1087 static OpenCLAccessAttr *getOpenCLArgAccess(const Decl *D) {
1088     return D->getAttr<OpenCLAccessAttr>();
1089 }
1090 
1091 /// Returns true if pipe element type is different from the pointer.
1092 static bool checkOpenCLPipeArg(Sema &S, CallExpr *Call) {
1093   const Expr *Arg0 = Call->getArg(0);
1094   // First argument type should always be pipe.
1095   if (!Arg0->getType()->isPipeType()) {
1096     S.Diag(Call->getBeginLoc(), diag::err_opencl_builtin_pipe_first_arg)
1097         << Call->getDirectCallee() << Arg0->getSourceRange();
1098     return true;
1099   }
1100   OpenCLAccessAttr *AccessQual =
1101       getOpenCLArgAccess(cast<DeclRefExpr>(Arg0)->getDecl());
1102   // Validates the access qualifier is compatible with the call.
1103   // OpenCL v2.0 s6.13.16 - The access qualifiers for pipe should only be
1104   // read_only and write_only, and assumed to be read_only if no qualifier is
1105   // specified.
1106   switch (Call->getDirectCallee()->getBuiltinID()) {
1107   case Builtin::BIread_pipe:
1108   case Builtin::BIreserve_read_pipe:
1109   case Builtin::BIcommit_read_pipe:
1110   case Builtin::BIwork_group_reserve_read_pipe:
1111   case Builtin::BIsub_group_reserve_read_pipe:
1112   case Builtin::BIwork_group_commit_read_pipe:
1113   case Builtin::BIsub_group_commit_read_pipe:
1114     if (!(!AccessQual || AccessQual->isReadOnly())) {
1115       S.Diag(Arg0->getBeginLoc(),
1116              diag::err_opencl_builtin_pipe_invalid_access_modifier)
1117           << "read_only" << Arg0->getSourceRange();
1118       return true;
1119     }
1120     break;
1121   case Builtin::BIwrite_pipe:
1122   case Builtin::BIreserve_write_pipe:
1123   case Builtin::BIcommit_write_pipe:
1124   case Builtin::BIwork_group_reserve_write_pipe:
1125   case Builtin::BIsub_group_reserve_write_pipe:
1126   case Builtin::BIwork_group_commit_write_pipe:
1127   case Builtin::BIsub_group_commit_write_pipe:
1128     if (!(AccessQual && AccessQual->isWriteOnly())) {
1129       S.Diag(Arg0->getBeginLoc(),
1130              diag::err_opencl_builtin_pipe_invalid_access_modifier)
1131           << "write_only" << Arg0->getSourceRange();
1132       return true;
1133     }
1134     break;
1135   default:
1136     break;
1137   }
1138   return false;
1139 }
1140 
1141 /// Returns true if pipe element type is different from the pointer.
1142 static bool checkOpenCLPipePacketType(Sema &S, CallExpr *Call, unsigned Idx) {
1143   const Expr *Arg0 = Call->getArg(0);
1144   const Expr *ArgIdx = Call->getArg(Idx);
1145   const PipeType *PipeTy = cast<PipeType>(Arg0->getType());
1146   const QualType EltTy = PipeTy->getElementType();
1147   const PointerType *ArgTy = ArgIdx->getType()->getAs<PointerType>();
1148   // The Idx argument should be a pointer and the type of the pointer and
1149   // the type of pipe element should also be the same.
1150   if (!ArgTy ||
1151       !S.Context.hasSameType(
1152           EltTy, ArgTy->getPointeeType()->getCanonicalTypeInternal())) {
1153     S.Diag(Call->getBeginLoc(), diag::err_opencl_builtin_pipe_invalid_arg)
1154         << Call->getDirectCallee() << S.Context.getPointerType(EltTy)
1155         << ArgIdx->getType() << ArgIdx->getSourceRange();
1156     return true;
1157   }
1158   return false;
1159 }
1160 
1161 // Performs semantic analysis for the read/write_pipe call.
1162 // \param S Reference to the semantic analyzer.
1163 // \param Call A pointer to the builtin call.
1164 // \return True if a semantic error has been found, false otherwise.
1165 static bool SemaBuiltinRWPipe(Sema &S, CallExpr *Call) {
1166   // OpenCL v2.0 s6.13.16.2 - The built-in read/write
1167   // functions have two forms.
1168   switch (Call->getNumArgs()) {
1169   case 2:
1170     if (checkOpenCLPipeArg(S, Call))
1171       return true;
1172     // The call with 2 arguments should be
1173     // read/write_pipe(pipe T, T*).
1174     // Check packet type T.
1175     if (checkOpenCLPipePacketType(S, Call, 1))
1176       return true;
1177     break;
1178 
1179   case 4: {
1180     if (checkOpenCLPipeArg(S, Call))
1181       return true;
1182     // The call with 4 arguments should be
1183     // read/write_pipe(pipe T, reserve_id_t, uint, T*).
1184     // Check reserve_id_t.
1185     if (!Call->getArg(1)->getType()->isReserveIDT()) {
1186       S.Diag(Call->getBeginLoc(), diag::err_opencl_builtin_pipe_invalid_arg)
1187           << Call->getDirectCallee() << S.Context.OCLReserveIDTy
1188           << Call->getArg(1)->getType() << Call->getArg(1)->getSourceRange();
1189       return true;
1190     }
1191 
1192     // Check the index.
1193     const Expr *Arg2 = Call->getArg(2);
1194     if (!Arg2->getType()->isIntegerType() &&
1195         !Arg2->getType()->isUnsignedIntegerType()) {
1196       S.Diag(Call->getBeginLoc(), diag::err_opencl_builtin_pipe_invalid_arg)
1197           << Call->getDirectCallee() << S.Context.UnsignedIntTy
1198           << Arg2->getType() << Arg2->getSourceRange();
1199       return true;
1200     }
1201 
1202     // Check packet type T.
1203     if (checkOpenCLPipePacketType(S, Call, 3))
1204       return true;
1205   } break;
1206   default:
1207     S.Diag(Call->getBeginLoc(), diag::err_opencl_builtin_pipe_arg_num)
1208         << Call->getDirectCallee() << Call->getSourceRange();
1209     return true;
1210   }
1211 
1212   return false;
1213 }
1214 
1215 // Performs a semantic analysis on the {work_group_/sub_group_
1216 //        /_}reserve_{read/write}_pipe
1217 // \param S Reference to the semantic analyzer.
1218 // \param Call The call to the builtin function to be analyzed.
1219 // \return True if a semantic error was found, false otherwise.
1220 static bool SemaBuiltinReserveRWPipe(Sema &S, CallExpr *Call) {
1221   if (checkArgCount(S, Call, 2))
1222     return true;
1223 
1224   if (checkOpenCLPipeArg(S, Call))
1225     return true;
1226 
1227   // Check the reserve size.
1228   if (!Call->getArg(1)->getType()->isIntegerType() &&
1229       !Call->getArg(1)->getType()->isUnsignedIntegerType()) {
1230     S.Diag(Call->getBeginLoc(), diag::err_opencl_builtin_pipe_invalid_arg)
1231         << Call->getDirectCallee() << S.Context.UnsignedIntTy
1232         << Call->getArg(1)->getType() << Call->getArg(1)->getSourceRange();
1233     return true;
1234   }
1235 
1236   // Since return type of reserve_read/write_pipe built-in function is
1237   // reserve_id_t, which is not defined in the builtin def file , we used int
1238   // as return type and need to override the return type of these functions.
1239   Call->setType(S.Context.OCLReserveIDTy);
1240 
1241   return false;
1242 }
1243 
1244 // Performs a semantic analysis on {work_group_/sub_group_
1245 //        /_}commit_{read/write}_pipe
1246 // \param S Reference to the semantic analyzer.
1247 // \param Call The call to the builtin function to be analyzed.
1248 // \return True if a semantic error was found, false otherwise.
1249 static bool SemaBuiltinCommitRWPipe(Sema &S, CallExpr *Call) {
1250   if (checkArgCount(S, Call, 2))
1251     return true;
1252 
1253   if (checkOpenCLPipeArg(S, Call))
1254     return true;
1255 
1256   // Check reserve_id_t.
1257   if (!Call->getArg(1)->getType()->isReserveIDT()) {
1258     S.Diag(Call->getBeginLoc(), diag::err_opencl_builtin_pipe_invalid_arg)
1259         << Call->getDirectCallee() << S.Context.OCLReserveIDTy
1260         << Call->getArg(1)->getType() << Call->getArg(1)->getSourceRange();
1261     return true;
1262   }
1263 
1264   return false;
1265 }
1266 
1267 // Performs a semantic analysis on the call to built-in Pipe
1268 //        Query Functions.
1269 // \param S Reference to the semantic analyzer.
1270 // \param Call The call to the builtin function to be analyzed.
1271 // \return True if a semantic error was found, false otherwise.
1272 static bool SemaBuiltinPipePackets(Sema &S, CallExpr *Call) {
1273   if (checkArgCount(S, Call, 1))
1274     return true;
1275 
1276   if (!Call->getArg(0)->getType()->isPipeType()) {
1277     S.Diag(Call->getBeginLoc(), diag::err_opencl_builtin_pipe_first_arg)
1278         << Call->getDirectCallee() << Call->getArg(0)->getSourceRange();
1279     return true;
1280   }
1281 
1282   return false;
1283 }
1284 
1285 // OpenCL v2.0 s6.13.9 - Address space qualifier functions.
1286 // Performs semantic analysis for the to_global/local/private call.
1287 // \param S Reference to the semantic analyzer.
1288 // \param BuiltinID ID of the builtin function.
1289 // \param Call A pointer to the builtin call.
1290 // \return True if a semantic error has been found, false otherwise.
1291 static bool SemaOpenCLBuiltinToAddr(Sema &S, unsigned BuiltinID,
1292                                     CallExpr *Call) {
1293   if (checkArgCount(S, Call, 1))
1294     return true;
1295 
1296   auto RT = Call->getArg(0)->getType();
1297   if (!RT->isPointerType() || RT->getPointeeType()
1298       .getAddressSpace() == LangAS::opencl_constant) {
1299     S.Diag(Call->getBeginLoc(), diag::err_opencl_builtin_to_addr_invalid_arg)
1300         << Call->getArg(0) << Call->getDirectCallee() << Call->getSourceRange();
1301     return true;
1302   }
1303 
1304   if (RT->getPointeeType().getAddressSpace() != LangAS::opencl_generic) {
1305     S.Diag(Call->getArg(0)->getBeginLoc(),
1306            diag::warn_opencl_generic_address_space_arg)
1307         << Call->getDirectCallee()->getNameInfo().getAsString()
1308         << Call->getArg(0)->getSourceRange();
1309   }
1310 
1311   RT = RT->getPointeeType();
1312   auto Qual = RT.getQualifiers();
1313   switch (BuiltinID) {
1314   case Builtin::BIto_global:
1315     Qual.setAddressSpace(LangAS::opencl_global);
1316     break;
1317   case Builtin::BIto_local:
1318     Qual.setAddressSpace(LangAS::opencl_local);
1319     break;
1320   case Builtin::BIto_private:
1321     Qual.setAddressSpace(LangAS::opencl_private);
1322     break;
1323   default:
1324     llvm_unreachable("Invalid builtin function");
1325   }
1326   Call->setType(S.Context.getPointerType(S.Context.getQualifiedType(
1327       RT.getUnqualifiedType(), Qual)));
1328 
1329   return false;
1330 }
1331 
1332 static ExprResult SemaBuiltinLaunder(Sema &S, CallExpr *TheCall) {
1333   if (checkArgCount(S, TheCall, 1))
1334     return ExprError();
1335 
1336   // Compute __builtin_launder's parameter type from the argument.
1337   // The parameter type is:
1338   //  * The type of the argument if it's not an array or function type,
1339   //  Otherwise,
1340   //  * The decayed argument type.
1341   QualType ParamTy = [&]() {
1342     QualType ArgTy = TheCall->getArg(0)->getType();
1343     if (const ArrayType *Ty = ArgTy->getAsArrayTypeUnsafe())
1344       return S.Context.getPointerType(Ty->getElementType());
1345     if (ArgTy->isFunctionType()) {
1346       return S.Context.getPointerType(ArgTy);
1347     }
1348     return ArgTy;
1349   }();
1350 
1351   TheCall->setType(ParamTy);
1352 
1353   auto DiagSelect = [&]() -> llvm::Optional<unsigned> {
1354     if (!ParamTy->isPointerType())
1355       return 0;
1356     if (ParamTy->isFunctionPointerType())
1357       return 1;
1358     if (ParamTy->isVoidPointerType())
1359       return 2;
1360     return llvm::Optional<unsigned>{};
1361   }();
1362   if (DiagSelect.hasValue()) {
1363     S.Diag(TheCall->getBeginLoc(), diag::err_builtin_launder_invalid_arg)
1364         << DiagSelect.getValue() << TheCall->getSourceRange();
1365     return ExprError();
1366   }
1367 
1368   // We either have an incomplete class type, or we have a class template
1369   // whose instantiation has not been forced. Example:
1370   //
1371   //   template <class T> struct Foo { T value; };
1372   //   Foo<int> *p = nullptr;
1373   //   auto *d = __builtin_launder(p);
1374   if (S.RequireCompleteType(TheCall->getBeginLoc(), ParamTy->getPointeeType(),
1375                             diag::err_incomplete_type))
1376     return ExprError();
1377 
1378   assert(ParamTy->getPointeeType()->isObjectType() &&
1379          "Unhandled non-object pointer case");
1380 
1381   InitializedEntity Entity =
1382       InitializedEntity::InitializeParameter(S.Context, ParamTy, false);
1383   ExprResult Arg =
1384       S.PerformCopyInitialization(Entity, SourceLocation(), TheCall->getArg(0));
1385   if (Arg.isInvalid())
1386     return ExprError();
1387   TheCall->setArg(0, Arg.get());
1388 
1389   return TheCall;
1390 }
1391 
1392 // Emit an error and return true if the current architecture is not in the list
1393 // of supported architectures.
1394 static bool
1395 CheckBuiltinTargetSupport(Sema &S, unsigned BuiltinID, CallExpr *TheCall,
1396                           ArrayRef<llvm::Triple::ArchType> SupportedArchs) {
1397   llvm::Triple::ArchType CurArch =
1398       S.getASTContext().getTargetInfo().getTriple().getArch();
1399   if (llvm::is_contained(SupportedArchs, CurArch))
1400     return false;
1401   S.Diag(TheCall->getBeginLoc(), diag::err_builtin_target_unsupported)
1402       << TheCall->getSourceRange();
1403   return true;
1404 }
1405 
1406 static void CheckNonNullArgument(Sema &S, const Expr *ArgExpr,
1407                                  SourceLocation CallSiteLoc);
1408 
1409 bool Sema::CheckTSBuiltinFunctionCall(const TargetInfo &TI, unsigned BuiltinID,
1410                                       CallExpr *TheCall) {
1411   switch (TI.getTriple().getArch()) {
1412   default:
1413     // Some builtins don't require additional checking, so just consider these
1414     // acceptable.
1415     return false;
1416   case llvm::Triple::arm:
1417   case llvm::Triple::armeb:
1418   case llvm::Triple::thumb:
1419   case llvm::Triple::thumbeb:
1420     return CheckARMBuiltinFunctionCall(TI, BuiltinID, TheCall);
1421   case llvm::Triple::aarch64:
1422   case llvm::Triple::aarch64_32:
1423   case llvm::Triple::aarch64_be:
1424     return CheckAArch64BuiltinFunctionCall(TI, BuiltinID, TheCall);
1425   case llvm::Triple::bpfeb:
1426   case llvm::Triple::bpfel:
1427     return CheckBPFBuiltinFunctionCall(BuiltinID, TheCall);
1428   case llvm::Triple::hexagon:
1429     return CheckHexagonBuiltinFunctionCall(BuiltinID, TheCall);
1430   case llvm::Triple::mips:
1431   case llvm::Triple::mipsel:
1432   case llvm::Triple::mips64:
1433   case llvm::Triple::mips64el:
1434     return CheckMipsBuiltinFunctionCall(TI, BuiltinID, TheCall);
1435   case llvm::Triple::systemz:
1436     return CheckSystemZBuiltinFunctionCall(BuiltinID, TheCall);
1437   case llvm::Triple::x86:
1438   case llvm::Triple::x86_64:
1439     return CheckX86BuiltinFunctionCall(TI, BuiltinID, TheCall);
1440   case llvm::Triple::ppc:
1441   case llvm::Triple::ppcle:
1442   case llvm::Triple::ppc64:
1443   case llvm::Triple::ppc64le:
1444     return CheckPPCBuiltinFunctionCall(TI, BuiltinID, TheCall);
1445   case llvm::Triple::amdgcn:
1446     return CheckAMDGCNBuiltinFunctionCall(BuiltinID, TheCall);
1447   case llvm::Triple::riscv32:
1448   case llvm::Triple::riscv64:
1449     return CheckRISCVBuiltinFunctionCall(TI, BuiltinID, TheCall);
1450   }
1451 }
1452 
1453 ExprResult
1454 Sema::CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID,
1455                                CallExpr *TheCall) {
1456   ExprResult TheCallResult(TheCall);
1457 
1458   // Find out if any arguments are required to be integer constant expressions.
1459   unsigned ICEArguments = 0;
1460   ASTContext::GetBuiltinTypeError Error;
1461   Context.GetBuiltinType(BuiltinID, Error, &ICEArguments);
1462   if (Error != ASTContext::GE_None)
1463     ICEArguments = 0;  // Don't diagnose previously diagnosed errors.
1464 
1465   // If any arguments are required to be ICE's, check and diagnose.
1466   for (unsigned ArgNo = 0; ICEArguments != 0; ++ArgNo) {
1467     // Skip arguments not required to be ICE's.
1468     if ((ICEArguments & (1 << ArgNo)) == 0) continue;
1469 
1470     llvm::APSInt Result;
1471     if (SemaBuiltinConstantArg(TheCall, ArgNo, Result))
1472       return true;
1473     ICEArguments &= ~(1 << ArgNo);
1474   }
1475 
1476   switch (BuiltinID) {
1477   case Builtin::BI__builtin___CFStringMakeConstantString:
1478     assert(TheCall->getNumArgs() == 1 &&
1479            "Wrong # arguments to builtin CFStringMakeConstantString");
1480     if (CheckObjCString(TheCall->getArg(0)))
1481       return ExprError();
1482     break;
1483   case Builtin::BI__builtin_ms_va_start:
1484   case Builtin::BI__builtin_stdarg_start:
1485   case Builtin::BI__builtin_va_start:
1486     if (SemaBuiltinVAStart(BuiltinID, TheCall))
1487       return ExprError();
1488     break;
1489   case Builtin::BI__va_start: {
1490     switch (Context.getTargetInfo().getTriple().getArch()) {
1491     case llvm::Triple::aarch64:
1492     case llvm::Triple::arm:
1493     case llvm::Triple::thumb:
1494       if (SemaBuiltinVAStartARMMicrosoft(TheCall))
1495         return ExprError();
1496       break;
1497     default:
1498       if (SemaBuiltinVAStart(BuiltinID, TheCall))
1499         return ExprError();
1500       break;
1501     }
1502     break;
1503   }
1504 
1505   // The acquire, release, and no fence variants are ARM and AArch64 only.
1506   case Builtin::BI_interlockedbittestandset_acq:
1507   case Builtin::BI_interlockedbittestandset_rel:
1508   case Builtin::BI_interlockedbittestandset_nf:
1509   case Builtin::BI_interlockedbittestandreset_acq:
1510   case Builtin::BI_interlockedbittestandreset_rel:
1511   case Builtin::BI_interlockedbittestandreset_nf:
1512     if (CheckBuiltinTargetSupport(
1513             *this, BuiltinID, TheCall,
1514             {llvm::Triple::arm, llvm::Triple::thumb, llvm::Triple::aarch64}))
1515       return ExprError();
1516     break;
1517 
1518   // The 64-bit bittest variants are x64, ARM, and AArch64 only.
1519   case Builtin::BI_bittest64:
1520   case Builtin::BI_bittestandcomplement64:
1521   case Builtin::BI_bittestandreset64:
1522   case Builtin::BI_bittestandset64:
1523   case Builtin::BI_interlockedbittestandreset64:
1524   case Builtin::BI_interlockedbittestandset64:
1525     if (CheckBuiltinTargetSupport(*this, BuiltinID, TheCall,
1526                                   {llvm::Triple::x86_64, llvm::Triple::arm,
1527                                    llvm::Triple::thumb, llvm::Triple::aarch64}))
1528       return ExprError();
1529     break;
1530 
1531   case Builtin::BI__builtin_isgreater:
1532   case Builtin::BI__builtin_isgreaterequal:
1533   case Builtin::BI__builtin_isless:
1534   case Builtin::BI__builtin_islessequal:
1535   case Builtin::BI__builtin_islessgreater:
1536   case Builtin::BI__builtin_isunordered:
1537     if (SemaBuiltinUnorderedCompare(TheCall))
1538       return ExprError();
1539     break;
1540   case Builtin::BI__builtin_fpclassify:
1541     if (SemaBuiltinFPClassification(TheCall, 6))
1542       return ExprError();
1543     break;
1544   case Builtin::BI__builtin_isfinite:
1545   case Builtin::BI__builtin_isinf:
1546   case Builtin::BI__builtin_isinf_sign:
1547   case Builtin::BI__builtin_isnan:
1548   case Builtin::BI__builtin_isnormal:
1549   case Builtin::BI__builtin_signbit:
1550   case Builtin::BI__builtin_signbitf:
1551   case Builtin::BI__builtin_signbitl:
1552     if (SemaBuiltinFPClassification(TheCall, 1))
1553       return ExprError();
1554     break;
1555   case Builtin::BI__builtin_shufflevector:
1556     return SemaBuiltinShuffleVector(TheCall);
1557     // TheCall will be freed by the smart pointer here, but that's fine, since
1558     // SemaBuiltinShuffleVector guts it, but then doesn't release it.
1559   case Builtin::BI__builtin_prefetch:
1560     if (SemaBuiltinPrefetch(TheCall))
1561       return ExprError();
1562     break;
1563   case Builtin::BI__builtin_alloca_with_align:
1564     if (SemaBuiltinAllocaWithAlign(TheCall))
1565       return ExprError();
1566     LLVM_FALLTHROUGH;
1567   case Builtin::BI__builtin_alloca:
1568     Diag(TheCall->getBeginLoc(), diag::warn_alloca)
1569         << TheCall->getDirectCallee();
1570     break;
1571   case Builtin::BI__arithmetic_fence:
1572     if (SemaBuiltinArithmeticFence(TheCall))
1573       return ExprError();
1574     break;
1575   case Builtin::BI__assume:
1576   case Builtin::BI__builtin_assume:
1577     if (SemaBuiltinAssume(TheCall))
1578       return ExprError();
1579     break;
1580   case Builtin::BI__builtin_assume_aligned:
1581     if (SemaBuiltinAssumeAligned(TheCall))
1582       return ExprError();
1583     break;
1584   case Builtin::BI__builtin_dynamic_object_size:
1585   case Builtin::BI__builtin_object_size:
1586     if (SemaBuiltinConstantArgRange(TheCall, 1, 0, 3))
1587       return ExprError();
1588     break;
1589   case Builtin::BI__builtin_longjmp:
1590     if (SemaBuiltinLongjmp(TheCall))
1591       return ExprError();
1592     break;
1593   case Builtin::BI__builtin_setjmp:
1594     if (SemaBuiltinSetjmp(TheCall))
1595       return ExprError();
1596     break;
1597   case Builtin::BI__builtin_classify_type:
1598     if (checkArgCount(*this, TheCall, 1)) return true;
1599     TheCall->setType(Context.IntTy);
1600     break;
1601   case Builtin::BI__builtin_complex:
1602     if (SemaBuiltinComplex(TheCall))
1603       return ExprError();
1604     break;
1605   case Builtin::BI__builtin_constant_p: {
1606     if (checkArgCount(*this, TheCall, 1)) return true;
1607     ExprResult Arg = DefaultFunctionArrayLvalueConversion(TheCall->getArg(0));
1608     if (Arg.isInvalid()) return true;
1609     TheCall->setArg(0, Arg.get());
1610     TheCall->setType(Context.IntTy);
1611     break;
1612   }
1613   case Builtin::BI__builtin_launder:
1614     return SemaBuiltinLaunder(*this, TheCall);
1615   case Builtin::BI__sync_fetch_and_add:
1616   case Builtin::BI__sync_fetch_and_add_1:
1617   case Builtin::BI__sync_fetch_and_add_2:
1618   case Builtin::BI__sync_fetch_and_add_4:
1619   case Builtin::BI__sync_fetch_and_add_8:
1620   case Builtin::BI__sync_fetch_and_add_16:
1621   case Builtin::BI__sync_fetch_and_sub:
1622   case Builtin::BI__sync_fetch_and_sub_1:
1623   case Builtin::BI__sync_fetch_and_sub_2:
1624   case Builtin::BI__sync_fetch_and_sub_4:
1625   case Builtin::BI__sync_fetch_and_sub_8:
1626   case Builtin::BI__sync_fetch_and_sub_16:
1627   case Builtin::BI__sync_fetch_and_or:
1628   case Builtin::BI__sync_fetch_and_or_1:
1629   case Builtin::BI__sync_fetch_and_or_2:
1630   case Builtin::BI__sync_fetch_and_or_4:
1631   case Builtin::BI__sync_fetch_and_or_8:
1632   case Builtin::BI__sync_fetch_and_or_16:
1633   case Builtin::BI__sync_fetch_and_and:
1634   case Builtin::BI__sync_fetch_and_and_1:
1635   case Builtin::BI__sync_fetch_and_and_2:
1636   case Builtin::BI__sync_fetch_and_and_4:
1637   case Builtin::BI__sync_fetch_and_and_8:
1638   case Builtin::BI__sync_fetch_and_and_16:
1639   case Builtin::BI__sync_fetch_and_xor:
1640   case Builtin::BI__sync_fetch_and_xor_1:
1641   case Builtin::BI__sync_fetch_and_xor_2:
1642   case Builtin::BI__sync_fetch_and_xor_4:
1643   case Builtin::BI__sync_fetch_and_xor_8:
1644   case Builtin::BI__sync_fetch_and_xor_16:
1645   case Builtin::BI__sync_fetch_and_nand:
1646   case Builtin::BI__sync_fetch_and_nand_1:
1647   case Builtin::BI__sync_fetch_and_nand_2:
1648   case Builtin::BI__sync_fetch_and_nand_4:
1649   case Builtin::BI__sync_fetch_and_nand_8:
1650   case Builtin::BI__sync_fetch_and_nand_16:
1651   case Builtin::BI__sync_add_and_fetch:
1652   case Builtin::BI__sync_add_and_fetch_1:
1653   case Builtin::BI__sync_add_and_fetch_2:
1654   case Builtin::BI__sync_add_and_fetch_4:
1655   case Builtin::BI__sync_add_and_fetch_8:
1656   case Builtin::BI__sync_add_and_fetch_16:
1657   case Builtin::BI__sync_sub_and_fetch:
1658   case Builtin::BI__sync_sub_and_fetch_1:
1659   case Builtin::BI__sync_sub_and_fetch_2:
1660   case Builtin::BI__sync_sub_and_fetch_4:
1661   case Builtin::BI__sync_sub_and_fetch_8:
1662   case Builtin::BI__sync_sub_and_fetch_16:
1663   case Builtin::BI__sync_and_and_fetch:
1664   case Builtin::BI__sync_and_and_fetch_1:
1665   case Builtin::BI__sync_and_and_fetch_2:
1666   case Builtin::BI__sync_and_and_fetch_4:
1667   case Builtin::BI__sync_and_and_fetch_8:
1668   case Builtin::BI__sync_and_and_fetch_16:
1669   case Builtin::BI__sync_or_and_fetch:
1670   case Builtin::BI__sync_or_and_fetch_1:
1671   case Builtin::BI__sync_or_and_fetch_2:
1672   case Builtin::BI__sync_or_and_fetch_4:
1673   case Builtin::BI__sync_or_and_fetch_8:
1674   case Builtin::BI__sync_or_and_fetch_16:
1675   case Builtin::BI__sync_xor_and_fetch:
1676   case Builtin::BI__sync_xor_and_fetch_1:
1677   case Builtin::BI__sync_xor_and_fetch_2:
1678   case Builtin::BI__sync_xor_and_fetch_4:
1679   case Builtin::BI__sync_xor_and_fetch_8:
1680   case Builtin::BI__sync_xor_and_fetch_16:
1681   case Builtin::BI__sync_nand_and_fetch:
1682   case Builtin::BI__sync_nand_and_fetch_1:
1683   case Builtin::BI__sync_nand_and_fetch_2:
1684   case Builtin::BI__sync_nand_and_fetch_4:
1685   case Builtin::BI__sync_nand_and_fetch_8:
1686   case Builtin::BI__sync_nand_and_fetch_16:
1687   case Builtin::BI__sync_val_compare_and_swap:
1688   case Builtin::BI__sync_val_compare_and_swap_1:
1689   case Builtin::BI__sync_val_compare_and_swap_2:
1690   case Builtin::BI__sync_val_compare_and_swap_4:
1691   case Builtin::BI__sync_val_compare_and_swap_8:
1692   case Builtin::BI__sync_val_compare_and_swap_16:
1693   case Builtin::BI__sync_bool_compare_and_swap:
1694   case Builtin::BI__sync_bool_compare_and_swap_1:
1695   case Builtin::BI__sync_bool_compare_and_swap_2:
1696   case Builtin::BI__sync_bool_compare_and_swap_4:
1697   case Builtin::BI__sync_bool_compare_and_swap_8:
1698   case Builtin::BI__sync_bool_compare_and_swap_16:
1699   case Builtin::BI__sync_lock_test_and_set:
1700   case Builtin::BI__sync_lock_test_and_set_1:
1701   case Builtin::BI__sync_lock_test_and_set_2:
1702   case Builtin::BI__sync_lock_test_and_set_4:
1703   case Builtin::BI__sync_lock_test_and_set_8:
1704   case Builtin::BI__sync_lock_test_and_set_16:
1705   case Builtin::BI__sync_lock_release:
1706   case Builtin::BI__sync_lock_release_1:
1707   case Builtin::BI__sync_lock_release_2:
1708   case Builtin::BI__sync_lock_release_4:
1709   case Builtin::BI__sync_lock_release_8:
1710   case Builtin::BI__sync_lock_release_16:
1711   case Builtin::BI__sync_swap:
1712   case Builtin::BI__sync_swap_1:
1713   case Builtin::BI__sync_swap_2:
1714   case Builtin::BI__sync_swap_4:
1715   case Builtin::BI__sync_swap_8:
1716   case Builtin::BI__sync_swap_16:
1717     return SemaBuiltinAtomicOverloaded(TheCallResult);
1718   case Builtin::BI__sync_synchronize:
1719     Diag(TheCall->getBeginLoc(), diag::warn_atomic_implicit_seq_cst)
1720         << TheCall->getCallee()->getSourceRange();
1721     break;
1722   case Builtin::BI__builtin_nontemporal_load:
1723   case Builtin::BI__builtin_nontemporal_store:
1724     return SemaBuiltinNontemporalOverloaded(TheCallResult);
1725   case Builtin::BI__builtin_memcpy_inline: {
1726     clang::Expr *SizeOp = TheCall->getArg(2);
1727     // We warn about copying to or from `nullptr` pointers when `size` is
1728     // greater than 0. When `size` is value dependent we cannot evaluate its
1729     // value so we bail out.
1730     if (SizeOp->isValueDependent())
1731       break;
1732     if (!SizeOp->EvaluateKnownConstInt(Context).isNullValue()) {
1733       CheckNonNullArgument(*this, TheCall->getArg(0), TheCall->getExprLoc());
1734       CheckNonNullArgument(*this, TheCall->getArg(1), TheCall->getExprLoc());
1735     }
1736     break;
1737   }
1738 #define BUILTIN(ID, TYPE, ATTRS)
1739 #define ATOMIC_BUILTIN(ID, TYPE, ATTRS) \
1740   case Builtin::BI##ID: \
1741     return SemaAtomicOpsOverloaded(TheCallResult, AtomicExpr::AO##ID);
1742 #include "clang/Basic/Builtins.def"
1743   case Builtin::BI__annotation:
1744     if (SemaBuiltinMSVCAnnotation(*this, TheCall))
1745       return ExprError();
1746     break;
1747   case Builtin::BI__builtin_annotation:
1748     if (SemaBuiltinAnnotation(*this, TheCall))
1749       return ExprError();
1750     break;
1751   case Builtin::BI__builtin_addressof:
1752     if (SemaBuiltinAddressof(*this, TheCall))
1753       return ExprError();
1754     break;
1755   case Builtin::BI__builtin_is_aligned:
1756   case Builtin::BI__builtin_align_up:
1757   case Builtin::BI__builtin_align_down:
1758     if (SemaBuiltinAlignment(*this, TheCall, BuiltinID))
1759       return ExprError();
1760     break;
1761   case Builtin::BI__builtin_add_overflow:
1762   case Builtin::BI__builtin_sub_overflow:
1763   case Builtin::BI__builtin_mul_overflow:
1764     if (SemaBuiltinOverflow(*this, TheCall, BuiltinID))
1765       return ExprError();
1766     break;
1767   case Builtin::BI__builtin_operator_new:
1768   case Builtin::BI__builtin_operator_delete: {
1769     bool IsDelete = BuiltinID == Builtin::BI__builtin_operator_delete;
1770     ExprResult Res =
1771         SemaBuiltinOperatorNewDeleteOverloaded(TheCallResult, IsDelete);
1772     if (Res.isInvalid())
1773       CorrectDelayedTyposInExpr(TheCallResult.get());
1774     return Res;
1775   }
1776   case Builtin::BI__builtin_dump_struct: {
1777     // We first want to ensure we are called with 2 arguments
1778     if (checkArgCount(*this, TheCall, 2))
1779       return ExprError();
1780     // Ensure that the first argument is of type 'struct XX *'
1781     const Expr *PtrArg = TheCall->getArg(0)->IgnoreParenImpCasts();
1782     const QualType PtrArgType = PtrArg->getType();
1783     if (!PtrArgType->isPointerType() ||
1784         !PtrArgType->getPointeeType()->isRecordType()) {
1785       Diag(PtrArg->getBeginLoc(), diag::err_typecheck_convert_incompatible)
1786           << PtrArgType << "structure pointer" << 1 << 0 << 3 << 1 << PtrArgType
1787           << "structure pointer";
1788       return ExprError();
1789     }
1790 
1791     // Ensure that the second argument is of type 'FunctionType'
1792     const Expr *FnPtrArg = TheCall->getArg(1)->IgnoreImpCasts();
1793     const QualType FnPtrArgType = FnPtrArg->getType();
1794     if (!FnPtrArgType->isPointerType()) {
1795       Diag(FnPtrArg->getBeginLoc(), diag::err_typecheck_convert_incompatible)
1796           << FnPtrArgType << "'int (*)(const char *, ...)'" << 1 << 0 << 3 << 2
1797           << FnPtrArgType << "'int (*)(const char *, ...)'";
1798       return ExprError();
1799     }
1800 
1801     const auto *FuncType =
1802         FnPtrArgType->getPointeeType()->getAs<FunctionType>();
1803 
1804     if (!FuncType) {
1805       Diag(FnPtrArg->getBeginLoc(), diag::err_typecheck_convert_incompatible)
1806           << FnPtrArgType << "'int (*)(const char *, ...)'" << 1 << 0 << 3 << 2
1807           << FnPtrArgType << "'int (*)(const char *, ...)'";
1808       return ExprError();
1809     }
1810 
1811     if (const auto *FT = dyn_cast<FunctionProtoType>(FuncType)) {
1812       if (!FT->getNumParams()) {
1813         Diag(FnPtrArg->getBeginLoc(), diag::err_typecheck_convert_incompatible)
1814             << FnPtrArgType << "'int (*)(const char *, ...)'" << 1 << 0 << 3
1815             << 2 << FnPtrArgType << "'int (*)(const char *, ...)'";
1816         return ExprError();
1817       }
1818       QualType PT = FT->getParamType(0);
1819       if (!FT->isVariadic() || FT->getReturnType() != Context.IntTy ||
1820           !PT->isPointerType() || !PT->getPointeeType()->isCharType() ||
1821           !PT->getPointeeType().isConstQualified()) {
1822         Diag(FnPtrArg->getBeginLoc(), diag::err_typecheck_convert_incompatible)
1823             << FnPtrArgType << "'int (*)(const char *, ...)'" << 1 << 0 << 3
1824             << 2 << FnPtrArgType << "'int (*)(const char *, ...)'";
1825         return ExprError();
1826       }
1827     }
1828 
1829     TheCall->setType(Context.IntTy);
1830     break;
1831   }
1832   case Builtin::BI__builtin_expect_with_probability: {
1833     // We first want to ensure we are called with 3 arguments
1834     if (checkArgCount(*this, TheCall, 3))
1835       return ExprError();
1836     // then check probability is constant float in range [0.0, 1.0]
1837     const Expr *ProbArg = TheCall->getArg(2);
1838     SmallVector<PartialDiagnosticAt, 8> Notes;
1839     Expr::EvalResult Eval;
1840     Eval.Diag = &Notes;
1841     if ((!ProbArg->EvaluateAsConstantExpr(Eval, Context)) ||
1842         !Eval.Val.isFloat()) {
1843       Diag(ProbArg->getBeginLoc(), diag::err_probability_not_constant_float)
1844           << ProbArg->getSourceRange();
1845       for (const PartialDiagnosticAt &PDiag : Notes)
1846         Diag(PDiag.first, PDiag.second);
1847       return ExprError();
1848     }
1849     llvm::APFloat Probability = Eval.Val.getFloat();
1850     bool LoseInfo = false;
1851     Probability.convert(llvm::APFloat::IEEEdouble(),
1852                         llvm::RoundingMode::Dynamic, &LoseInfo);
1853     if (!(Probability >= llvm::APFloat(0.0) &&
1854           Probability <= llvm::APFloat(1.0))) {
1855       Diag(ProbArg->getBeginLoc(), diag::err_probability_out_of_range)
1856           << ProbArg->getSourceRange();
1857       return ExprError();
1858     }
1859     break;
1860   }
1861   case Builtin::BI__builtin_preserve_access_index:
1862     if (SemaBuiltinPreserveAI(*this, TheCall))
1863       return ExprError();
1864     break;
1865   case Builtin::BI__builtin_call_with_static_chain:
1866     if (SemaBuiltinCallWithStaticChain(*this, TheCall))
1867       return ExprError();
1868     break;
1869   case Builtin::BI__exception_code:
1870   case Builtin::BI_exception_code:
1871     if (SemaBuiltinSEHScopeCheck(*this, TheCall, Scope::SEHExceptScope,
1872                                  diag::err_seh___except_block))
1873       return ExprError();
1874     break;
1875   case Builtin::BI__exception_info:
1876   case Builtin::BI_exception_info:
1877     if (SemaBuiltinSEHScopeCheck(*this, TheCall, Scope::SEHFilterScope,
1878                                  diag::err_seh___except_filter))
1879       return ExprError();
1880     break;
1881   case Builtin::BI__GetExceptionInfo:
1882     if (checkArgCount(*this, TheCall, 1))
1883       return ExprError();
1884 
1885     if (CheckCXXThrowOperand(
1886             TheCall->getBeginLoc(),
1887             Context.getExceptionObjectType(FDecl->getParamDecl(0)->getType()),
1888             TheCall))
1889       return ExprError();
1890 
1891     TheCall->setType(Context.VoidPtrTy);
1892     break;
1893   // OpenCL v2.0, s6.13.16 - Pipe functions
1894   case Builtin::BIread_pipe:
1895   case Builtin::BIwrite_pipe:
1896     // Since those two functions are declared with var args, we need a semantic
1897     // check for the argument.
1898     if (SemaBuiltinRWPipe(*this, TheCall))
1899       return ExprError();
1900     break;
1901   case Builtin::BIreserve_read_pipe:
1902   case Builtin::BIreserve_write_pipe:
1903   case Builtin::BIwork_group_reserve_read_pipe:
1904   case Builtin::BIwork_group_reserve_write_pipe:
1905     if (SemaBuiltinReserveRWPipe(*this, TheCall))
1906       return ExprError();
1907     break;
1908   case Builtin::BIsub_group_reserve_read_pipe:
1909   case Builtin::BIsub_group_reserve_write_pipe:
1910     if (checkOpenCLSubgroupExt(*this, TheCall) ||
1911         SemaBuiltinReserveRWPipe(*this, TheCall))
1912       return ExprError();
1913     break;
1914   case Builtin::BIcommit_read_pipe:
1915   case Builtin::BIcommit_write_pipe:
1916   case Builtin::BIwork_group_commit_read_pipe:
1917   case Builtin::BIwork_group_commit_write_pipe:
1918     if (SemaBuiltinCommitRWPipe(*this, TheCall))
1919       return ExprError();
1920     break;
1921   case Builtin::BIsub_group_commit_read_pipe:
1922   case Builtin::BIsub_group_commit_write_pipe:
1923     if (checkOpenCLSubgroupExt(*this, TheCall) ||
1924         SemaBuiltinCommitRWPipe(*this, TheCall))
1925       return ExprError();
1926     break;
1927   case Builtin::BIget_pipe_num_packets:
1928   case Builtin::BIget_pipe_max_packets:
1929     if (SemaBuiltinPipePackets(*this, TheCall))
1930       return ExprError();
1931     break;
1932   case Builtin::BIto_global:
1933   case Builtin::BIto_local:
1934   case Builtin::BIto_private:
1935     if (SemaOpenCLBuiltinToAddr(*this, BuiltinID, TheCall))
1936       return ExprError();
1937     break;
1938   // OpenCL v2.0, s6.13.17 - Enqueue kernel functions.
1939   case Builtin::BIenqueue_kernel:
1940     if (SemaOpenCLBuiltinEnqueueKernel(*this, TheCall))
1941       return ExprError();
1942     break;
1943   case Builtin::BIget_kernel_work_group_size:
1944   case Builtin::BIget_kernel_preferred_work_group_size_multiple:
1945     if (SemaOpenCLBuiltinKernelWorkGroupSize(*this, TheCall))
1946       return ExprError();
1947     break;
1948   case Builtin::BIget_kernel_max_sub_group_size_for_ndrange:
1949   case Builtin::BIget_kernel_sub_group_count_for_ndrange:
1950     if (SemaOpenCLBuiltinNDRangeAndBlock(*this, TheCall))
1951       return ExprError();
1952     break;
1953   case Builtin::BI__builtin_os_log_format:
1954     Cleanup.setExprNeedsCleanups(true);
1955     LLVM_FALLTHROUGH;
1956   case Builtin::BI__builtin_os_log_format_buffer_size:
1957     if (SemaBuiltinOSLogFormat(TheCall))
1958       return ExprError();
1959     break;
1960   case Builtin::BI__builtin_frame_address:
1961   case Builtin::BI__builtin_return_address: {
1962     if (SemaBuiltinConstantArgRange(TheCall, 0, 0, 0xFFFF))
1963       return ExprError();
1964 
1965     // -Wframe-address warning if non-zero passed to builtin
1966     // return/frame address.
1967     Expr::EvalResult Result;
1968     if (!TheCall->getArg(0)->isValueDependent() &&
1969         TheCall->getArg(0)->EvaluateAsInt(Result, getASTContext()) &&
1970         Result.Val.getInt() != 0)
1971       Diag(TheCall->getBeginLoc(), diag::warn_frame_address)
1972           << ((BuiltinID == Builtin::BI__builtin_return_address)
1973                   ? "__builtin_return_address"
1974                   : "__builtin_frame_address")
1975           << TheCall->getSourceRange();
1976     break;
1977   }
1978 
1979   case Builtin::BI__builtin_matrix_transpose:
1980     return SemaBuiltinMatrixTranspose(TheCall, TheCallResult);
1981 
1982   case Builtin::BI__builtin_matrix_column_major_load:
1983     return SemaBuiltinMatrixColumnMajorLoad(TheCall, TheCallResult);
1984 
1985   case Builtin::BI__builtin_matrix_column_major_store:
1986     return SemaBuiltinMatrixColumnMajorStore(TheCall, TheCallResult);
1987 
1988   case Builtin::BI__builtin_get_device_side_mangled_name: {
1989     auto Check = [](CallExpr *TheCall) {
1990       if (TheCall->getNumArgs() != 1)
1991         return false;
1992       auto *DRE = dyn_cast<DeclRefExpr>(TheCall->getArg(0)->IgnoreImpCasts());
1993       if (!DRE)
1994         return false;
1995       auto *D = DRE->getDecl();
1996       if (!isa<FunctionDecl>(D) && !isa<VarDecl>(D))
1997         return false;
1998       return D->hasAttr<CUDAGlobalAttr>() || D->hasAttr<CUDADeviceAttr>() ||
1999              D->hasAttr<CUDAConstantAttr>() || D->hasAttr<HIPManagedAttr>();
2000     };
2001     if (!Check(TheCall)) {
2002       Diag(TheCall->getBeginLoc(),
2003            diag::err_hip_invalid_args_builtin_mangled_name);
2004       return ExprError();
2005     }
2006   }
2007   }
2008 
2009   // Since the target specific builtins for each arch overlap, only check those
2010   // of the arch we are compiling for.
2011   if (Context.BuiltinInfo.isTSBuiltin(BuiltinID)) {
2012     if (Context.BuiltinInfo.isAuxBuiltinID(BuiltinID)) {
2013       assert(Context.getAuxTargetInfo() &&
2014              "Aux Target Builtin, but not an aux target?");
2015 
2016       if (CheckTSBuiltinFunctionCall(
2017               *Context.getAuxTargetInfo(),
2018               Context.BuiltinInfo.getAuxBuiltinID(BuiltinID), TheCall))
2019         return ExprError();
2020     } else {
2021       if (CheckTSBuiltinFunctionCall(Context.getTargetInfo(), BuiltinID,
2022                                      TheCall))
2023         return ExprError();
2024     }
2025   }
2026 
2027   return TheCallResult;
2028 }
2029 
2030 // Get the valid immediate range for the specified NEON type code.
2031 static unsigned RFT(unsigned t, bool shift = false, bool ForceQuad = false) {
2032   NeonTypeFlags Type(t);
2033   int IsQuad = ForceQuad ? true : Type.isQuad();
2034   switch (Type.getEltType()) {
2035   case NeonTypeFlags::Int8:
2036   case NeonTypeFlags::Poly8:
2037     return shift ? 7 : (8 << IsQuad) - 1;
2038   case NeonTypeFlags::Int16:
2039   case NeonTypeFlags::Poly16:
2040     return shift ? 15 : (4 << IsQuad) - 1;
2041   case NeonTypeFlags::Int32:
2042     return shift ? 31 : (2 << IsQuad) - 1;
2043   case NeonTypeFlags::Int64:
2044   case NeonTypeFlags::Poly64:
2045     return shift ? 63 : (1 << IsQuad) - 1;
2046   case NeonTypeFlags::Poly128:
2047     return shift ? 127 : (1 << IsQuad) - 1;
2048   case NeonTypeFlags::Float16:
2049     assert(!shift && "cannot shift float types!");
2050     return (4 << IsQuad) - 1;
2051   case NeonTypeFlags::Float32:
2052     assert(!shift && "cannot shift float types!");
2053     return (2 << IsQuad) - 1;
2054   case NeonTypeFlags::Float64:
2055     assert(!shift && "cannot shift float types!");
2056     return (1 << IsQuad) - 1;
2057   case NeonTypeFlags::BFloat16:
2058     assert(!shift && "cannot shift float types!");
2059     return (4 << IsQuad) - 1;
2060   }
2061   llvm_unreachable("Invalid NeonTypeFlag!");
2062 }
2063 
2064 /// getNeonEltType - Return the QualType corresponding to the elements of
2065 /// the vector type specified by the NeonTypeFlags.  This is used to check
2066 /// the pointer arguments for Neon load/store intrinsics.
2067 static QualType getNeonEltType(NeonTypeFlags Flags, ASTContext &Context,
2068                                bool IsPolyUnsigned, bool IsInt64Long) {
2069   switch (Flags.getEltType()) {
2070   case NeonTypeFlags::Int8:
2071     return Flags.isUnsigned() ? Context.UnsignedCharTy : Context.SignedCharTy;
2072   case NeonTypeFlags::Int16:
2073     return Flags.isUnsigned() ? Context.UnsignedShortTy : Context.ShortTy;
2074   case NeonTypeFlags::Int32:
2075     return Flags.isUnsigned() ? Context.UnsignedIntTy : Context.IntTy;
2076   case NeonTypeFlags::Int64:
2077     if (IsInt64Long)
2078       return Flags.isUnsigned() ? Context.UnsignedLongTy : Context.LongTy;
2079     else
2080       return Flags.isUnsigned() ? Context.UnsignedLongLongTy
2081                                 : Context.LongLongTy;
2082   case NeonTypeFlags::Poly8:
2083     return IsPolyUnsigned ? Context.UnsignedCharTy : Context.SignedCharTy;
2084   case NeonTypeFlags::Poly16:
2085     return IsPolyUnsigned ? Context.UnsignedShortTy : Context.ShortTy;
2086   case NeonTypeFlags::Poly64:
2087     if (IsInt64Long)
2088       return Context.UnsignedLongTy;
2089     else
2090       return Context.UnsignedLongLongTy;
2091   case NeonTypeFlags::Poly128:
2092     break;
2093   case NeonTypeFlags::Float16:
2094     return Context.HalfTy;
2095   case NeonTypeFlags::Float32:
2096     return Context.FloatTy;
2097   case NeonTypeFlags::Float64:
2098     return Context.DoubleTy;
2099   case NeonTypeFlags::BFloat16:
2100     return Context.BFloat16Ty;
2101   }
2102   llvm_unreachable("Invalid NeonTypeFlag!");
2103 }
2104 
2105 bool Sema::CheckSVEBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
2106   // Range check SVE intrinsics that take immediate values.
2107   SmallVector<std::tuple<int,int,int>, 3> ImmChecks;
2108 
2109   switch (BuiltinID) {
2110   default:
2111     return false;
2112 #define GET_SVE_IMMEDIATE_CHECK
2113 #include "clang/Basic/arm_sve_sema_rangechecks.inc"
2114 #undef GET_SVE_IMMEDIATE_CHECK
2115   }
2116 
2117   // Perform all the immediate checks for this builtin call.
2118   bool HasError = false;
2119   for (auto &I : ImmChecks) {
2120     int ArgNum, CheckTy, ElementSizeInBits;
2121     std::tie(ArgNum, CheckTy, ElementSizeInBits) = I;
2122 
2123     typedef bool(*OptionSetCheckFnTy)(int64_t Value);
2124 
2125     // Function that checks whether the operand (ArgNum) is an immediate
2126     // that is one of the predefined values.
2127     auto CheckImmediateInSet = [&](OptionSetCheckFnTy CheckImm,
2128                                    int ErrDiag) -> bool {
2129       // We can't check the value of a dependent argument.
2130       Expr *Arg = TheCall->getArg(ArgNum);
2131       if (Arg->isTypeDependent() || Arg->isValueDependent())
2132         return false;
2133 
2134       // Check constant-ness first.
2135       llvm::APSInt Imm;
2136       if (SemaBuiltinConstantArg(TheCall, ArgNum, Imm))
2137         return true;
2138 
2139       if (!CheckImm(Imm.getSExtValue()))
2140         return Diag(TheCall->getBeginLoc(), ErrDiag) << Arg->getSourceRange();
2141       return false;
2142     };
2143 
2144     switch ((SVETypeFlags::ImmCheckType)CheckTy) {
2145     case SVETypeFlags::ImmCheck0_31:
2146       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0, 31))
2147         HasError = true;
2148       break;
2149     case SVETypeFlags::ImmCheck0_13:
2150       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0, 13))
2151         HasError = true;
2152       break;
2153     case SVETypeFlags::ImmCheck1_16:
2154       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 1, 16))
2155         HasError = true;
2156       break;
2157     case SVETypeFlags::ImmCheck0_7:
2158       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0, 7))
2159         HasError = true;
2160       break;
2161     case SVETypeFlags::ImmCheckExtract:
2162       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0,
2163                                       (2048 / ElementSizeInBits) - 1))
2164         HasError = true;
2165       break;
2166     case SVETypeFlags::ImmCheckShiftRight:
2167       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 1, ElementSizeInBits))
2168         HasError = true;
2169       break;
2170     case SVETypeFlags::ImmCheckShiftRightNarrow:
2171       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 1,
2172                                       ElementSizeInBits / 2))
2173         HasError = true;
2174       break;
2175     case SVETypeFlags::ImmCheckShiftLeft:
2176       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0,
2177                                       ElementSizeInBits - 1))
2178         HasError = true;
2179       break;
2180     case SVETypeFlags::ImmCheckLaneIndex:
2181       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0,
2182                                       (128 / (1 * ElementSizeInBits)) - 1))
2183         HasError = true;
2184       break;
2185     case SVETypeFlags::ImmCheckLaneIndexCompRotate:
2186       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0,
2187                                       (128 / (2 * ElementSizeInBits)) - 1))
2188         HasError = true;
2189       break;
2190     case SVETypeFlags::ImmCheckLaneIndexDot:
2191       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0,
2192                                       (128 / (4 * ElementSizeInBits)) - 1))
2193         HasError = true;
2194       break;
2195     case SVETypeFlags::ImmCheckComplexRot90_270:
2196       if (CheckImmediateInSet([](int64_t V) { return V == 90 || V == 270; },
2197                               diag::err_rotation_argument_to_cadd))
2198         HasError = true;
2199       break;
2200     case SVETypeFlags::ImmCheckComplexRotAll90:
2201       if (CheckImmediateInSet(
2202               [](int64_t V) {
2203                 return V == 0 || V == 90 || V == 180 || V == 270;
2204               },
2205               diag::err_rotation_argument_to_cmla))
2206         HasError = true;
2207       break;
2208     case SVETypeFlags::ImmCheck0_1:
2209       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0, 1))
2210         HasError = true;
2211       break;
2212     case SVETypeFlags::ImmCheck0_2:
2213       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0, 2))
2214         HasError = true;
2215       break;
2216     case SVETypeFlags::ImmCheck0_3:
2217       if (SemaBuiltinConstantArgRange(TheCall, ArgNum, 0, 3))
2218         HasError = true;
2219       break;
2220     }
2221   }
2222 
2223   return HasError;
2224 }
2225 
2226 bool Sema::CheckNeonBuiltinFunctionCall(const TargetInfo &TI,
2227                                         unsigned BuiltinID, CallExpr *TheCall) {
2228   llvm::APSInt Result;
2229   uint64_t mask = 0;
2230   unsigned TV = 0;
2231   int PtrArgNum = -1;
2232   bool HasConstPtr = false;
2233   switch (BuiltinID) {
2234 #define GET_NEON_OVERLOAD_CHECK
2235 #include "clang/Basic/arm_neon.inc"
2236 #include "clang/Basic/arm_fp16.inc"
2237 #undef GET_NEON_OVERLOAD_CHECK
2238   }
2239 
2240   // For NEON intrinsics which are overloaded on vector element type, validate
2241   // the immediate which specifies which variant to emit.
2242   unsigned ImmArg = TheCall->getNumArgs()-1;
2243   if (mask) {
2244     if (SemaBuiltinConstantArg(TheCall, ImmArg, Result))
2245       return true;
2246 
2247     TV = Result.getLimitedValue(64);
2248     if ((TV > 63) || (mask & (1ULL << TV)) == 0)
2249       return Diag(TheCall->getBeginLoc(), diag::err_invalid_neon_type_code)
2250              << TheCall->getArg(ImmArg)->getSourceRange();
2251   }
2252 
2253   if (PtrArgNum >= 0) {
2254     // Check that pointer arguments have the specified type.
2255     Expr *Arg = TheCall->getArg(PtrArgNum);
2256     if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Arg))
2257       Arg = ICE->getSubExpr();
2258     ExprResult RHS = DefaultFunctionArrayLvalueConversion(Arg);
2259     QualType RHSTy = RHS.get()->getType();
2260 
2261     llvm::Triple::ArchType Arch = TI.getTriple().getArch();
2262     bool IsPolyUnsigned = Arch == llvm::Triple::aarch64 ||
2263                           Arch == llvm::Triple::aarch64_32 ||
2264                           Arch == llvm::Triple::aarch64_be;
2265     bool IsInt64Long = TI.getInt64Type() == TargetInfo::SignedLong;
2266     QualType EltTy =
2267         getNeonEltType(NeonTypeFlags(TV), Context, IsPolyUnsigned, IsInt64Long);
2268     if (HasConstPtr)
2269       EltTy = EltTy.withConst();
2270     QualType LHSTy = Context.getPointerType(EltTy);
2271     AssignConvertType ConvTy;
2272     ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS);
2273     if (RHS.isInvalid())
2274       return true;
2275     if (DiagnoseAssignmentResult(ConvTy, Arg->getBeginLoc(), LHSTy, RHSTy,
2276                                  RHS.get(), AA_Assigning))
2277       return true;
2278   }
2279 
2280   // For NEON intrinsics which take an immediate value as part of the
2281   // instruction, range check them here.
2282   unsigned i = 0, l = 0, u = 0;
2283   switch (BuiltinID) {
2284   default:
2285     return false;
2286   #define GET_NEON_IMMEDIATE_CHECK
2287   #include "clang/Basic/arm_neon.inc"
2288   #include "clang/Basic/arm_fp16.inc"
2289   #undef GET_NEON_IMMEDIATE_CHECK
2290   }
2291 
2292   return SemaBuiltinConstantArgRange(TheCall, i, l, u + l);
2293 }
2294 
2295 bool Sema::CheckMVEBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
2296   switch (BuiltinID) {
2297   default:
2298     return false;
2299   #include "clang/Basic/arm_mve_builtin_sema.inc"
2300   }
2301 }
2302 
2303 bool Sema::CheckCDEBuiltinFunctionCall(const TargetInfo &TI, unsigned BuiltinID,
2304                                        CallExpr *TheCall) {
2305   bool Err = false;
2306   switch (BuiltinID) {
2307   default:
2308     return false;
2309 #include "clang/Basic/arm_cde_builtin_sema.inc"
2310   }
2311 
2312   if (Err)
2313     return true;
2314 
2315   return CheckARMCoprocessorImmediate(TI, TheCall->getArg(0), /*WantCDE*/ true);
2316 }
2317 
2318 bool Sema::CheckARMCoprocessorImmediate(const TargetInfo &TI,
2319                                         const Expr *CoprocArg, bool WantCDE) {
2320   if (isConstantEvaluated())
2321     return false;
2322 
2323   // We can't check the value of a dependent argument.
2324   if (CoprocArg->isTypeDependent() || CoprocArg->isValueDependent())
2325     return false;
2326 
2327   llvm::APSInt CoprocNoAP = *CoprocArg->getIntegerConstantExpr(Context);
2328   int64_t CoprocNo = CoprocNoAP.getExtValue();
2329   assert(CoprocNo >= 0 && "Coprocessor immediate must be non-negative");
2330 
2331   uint32_t CDECoprocMask = TI.getARMCDECoprocMask();
2332   bool IsCDECoproc = CoprocNo <= 7 && (CDECoprocMask & (1 << CoprocNo));
2333 
2334   if (IsCDECoproc != WantCDE)
2335     return Diag(CoprocArg->getBeginLoc(), diag::err_arm_invalid_coproc)
2336            << (int)CoprocNo << (int)WantCDE << CoprocArg->getSourceRange();
2337 
2338   return false;
2339 }
2340 
2341 bool Sema::CheckARMBuiltinExclusiveCall(unsigned BuiltinID, CallExpr *TheCall,
2342                                         unsigned MaxWidth) {
2343   assert((BuiltinID == ARM::BI__builtin_arm_ldrex ||
2344           BuiltinID == ARM::BI__builtin_arm_ldaex ||
2345           BuiltinID == ARM::BI__builtin_arm_strex ||
2346           BuiltinID == ARM::BI__builtin_arm_stlex ||
2347           BuiltinID == AArch64::BI__builtin_arm_ldrex ||
2348           BuiltinID == AArch64::BI__builtin_arm_ldaex ||
2349           BuiltinID == AArch64::BI__builtin_arm_strex ||
2350           BuiltinID == AArch64::BI__builtin_arm_stlex) &&
2351          "unexpected ARM builtin");
2352   bool IsLdrex = BuiltinID == ARM::BI__builtin_arm_ldrex ||
2353                  BuiltinID == ARM::BI__builtin_arm_ldaex ||
2354                  BuiltinID == AArch64::BI__builtin_arm_ldrex ||
2355                  BuiltinID == AArch64::BI__builtin_arm_ldaex;
2356 
2357   DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts());
2358 
2359   // Ensure that we have the proper number of arguments.
2360   if (checkArgCount(*this, TheCall, IsLdrex ? 1 : 2))
2361     return true;
2362 
2363   // Inspect the pointer argument of the atomic builtin.  This should always be
2364   // a pointer type, whose element is an integral scalar or pointer type.
2365   // Because it is a pointer type, we don't have to worry about any implicit
2366   // casts here.
2367   Expr *PointerArg = TheCall->getArg(IsLdrex ? 0 : 1);
2368   ExprResult PointerArgRes = DefaultFunctionArrayLvalueConversion(PointerArg);
2369   if (PointerArgRes.isInvalid())
2370     return true;
2371   PointerArg = PointerArgRes.get();
2372 
2373   const PointerType *pointerType = PointerArg->getType()->getAs<PointerType>();
2374   if (!pointerType) {
2375     Diag(DRE->getBeginLoc(), diag::err_atomic_builtin_must_be_pointer)
2376         << PointerArg->getType() << PointerArg->getSourceRange();
2377     return true;
2378   }
2379 
2380   // ldrex takes a "const volatile T*" and strex takes a "volatile T*". Our next
2381   // task is to insert the appropriate casts into the AST. First work out just
2382   // what the appropriate type is.
2383   QualType ValType = pointerType->getPointeeType();
2384   QualType AddrType = ValType.getUnqualifiedType().withVolatile();
2385   if (IsLdrex)
2386     AddrType.addConst();
2387 
2388   // Issue a warning if the cast is dodgy.
2389   CastKind CastNeeded = CK_NoOp;
2390   if (!AddrType.isAtLeastAsQualifiedAs(ValType)) {
2391     CastNeeded = CK_BitCast;
2392     Diag(DRE->getBeginLoc(), diag::ext_typecheck_convert_discards_qualifiers)
2393         << PointerArg->getType() << Context.getPointerType(AddrType)
2394         << AA_Passing << PointerArg->getSourceRange();
2395   }
2396 
2397   // Finally, do the cast and replace the argument with the corrected version.
2398   AddrType = Context.getPointerType(AddrType);
2399   PointerArgRes = ImpCastExprToType(PointerArg, AddrType, CastNeeded);
2400   if (PointerArgRes.isInvalid())
2401     return true;
2402   PointerArg = PointerArgRes.get();
2403 
2404   TheCall->setArg(IsLdrex ? 0 : 1, PointerArg);
2405 
2406   // In general, we allow ints, floats and pointers to be loaded and stored.
2407   if (!ValType->isIntegerType() && !ValType->isAnyPointerType() &&
2408       !ValType->isBlockPointerType() && !ValType->isFloatingType()) {
2409     Diag(DRE->getBeginLoc(), diag::err_atomic_builtin_must_be_pointer_intfltptr)
2410         << PointerArg->getType() << PointerArg->getSourceRange();
2411     return true;
2412   }
2413 
2414   // But ARM doesn't have instructions to deal with 128-bit versions.
2415   if (Context.getTypeSize(ValType) > MaxWidth) {
2416     assert(MaxWidth == 64 && "Diagnostic unexpectedly inaccurate");
2417     Diag(DRE->getBeginLoc(), diag::err_atomic_exclusive_builtin_pointer_size)
2418         << PointerArg->getType() << PointerArg->getSourceRange();
2419     return true;
2420   }
2421 
2422   switch (ValType.getObjCLifetime()) {
2423   case Qualifiers::OCL_None:
2424   case Qualifiers::OCL_ExplicitNone:
2425     // okay
2426     break;
2427 
2428   case Qualifiers::OCL_Weak:
2429   case Qualifiers::OCL_Strong:
2430   case Qualifiers::OCL_Autoreleasing:
2431     Diag(DRE->getBeginLoc(), diag::err_arc_atomic_ownership)
2432         << ValType << PointerArg->getSourceRange();
2433     return true;
2434   }
2435 
2436   if (IsLdrex) {
2437     TheCall->setType(ValType);
2438     return false;
2439   }
2440 
2441   // Initialize the argument to be stored.
2442   ExprResult ValArg = TheCall->getArg(0);
2443   InitializedEntity Entity = InitializedEntity::InitializeParameter(
2444       Context, ValType, /*consume*/ false);
2445   ValArg = PerformCopyInitialization(Entity, SourceLocation(), ValArg);
2446   if (ValArg.isInvalid())
2447     return true;
2448   TheCall->setArg(0, ValArg.get());
2449 
2450   // __builtin_arm_strex always returns an int. It's marked as such in the .def,
2451   // but the custom checker bypasses all default analysis.
2452   TheCall->setType(Context.IntTy);
2453   return false;
2454 }
2455 
2456 bool Sema::CheckARMBuiltinFunctionCall(const TargetInfo &TI, unsigned BuiltinID,
2457                                        CallExpr *TheCall) {
2458   if (BuiltinID == ARM::BI__builtin_arm_ldrex ||
2459       BuiltinID == ARM::BI__builtin_arm_ldaex ||
2460       BuiltinID == ARM::BI__builtin_arm_strex ||
2461       BuiltinID == ARM::BI__builtin_arm_stlex) {
2462     return CheckARMBuiltinExclusiveCall(BuiltinID, TheCall, 64);
2463   }
2464 
2465   if (BuiltinID == ARM::BI__builtin_arm_prefetch) {
2466     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1) ||
2467       SemaBuiltinConstantArgRange(TheCall, 2, 0, 1);
2468   }
2469 
2470   if (BuiltinID == ARM::BI__builtin_arm_rsr64 ||
2471       BuiltinID == ARM::BI__builtin_arm_wsr64)
2472     return SemaBuiltinARMSpecialReg(BuiltinID, TheCall, 0, 3, false);
2473 
2474   if (BuiltinID == ARM::BI__builtin_arm_rsr ||
2475       BuiltinID == ARM::BI__builtin_arm_rsrp ||
2476       BuiltinID == ARM::BI__builtin_arm_wsr ||
2477       BuiltinID == ARM::BI__builtin_arm_wsrp)
2478     return SemaBuiltinARMSpecialReg(BuiltinID, TheCall, 0, 5, true);
2479 
2480   if (CheckNeonBuiltinFunctionCall(TI, BuiltinID, TheCall))
2481     return true;
2482   if (CheckMVEBuiltinFunctionCall(BuiltinID, TheCall))
2483     return true;
2484   if (CheckCDEBuiltinFunctionCall(TI, BuiltinID, TheCall))
2485     return true;
2486 
2487   // For intrinsics which take an immediate value as part of the instruction,
2488   // range check them here.
2489   // FIXME: VFP Intrinsics should error if VFP not present.
2490   switch (BuiltinID) {
2491   default: return false;
2492   case ARM::BI__builtin_arm_ssat:
2493     return SemaBuiltinConstantArgRange(TheCall, 1, 1, 32);
2494   case ARM::BI__builtin_arm_usat:
2495     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 31);
2496   case ARM::BI__builtin_arm_ssat16:
2497     return SemaBuiltinConstantArgRange(TheCall, 1, 1, 16);
2498   case ARM::BI__builtin_arm_usat16:
2499     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 15);
2500   case ARM::BI__builtin_arm_vcvtr_f:
2501   case ARM::BI__builtin_arm_vcvtr_d:
2502     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1);
2503   case ARM::BI__builtin_arm_dmb:
2504   case ARM::BI__builtin_arm_dsb:
2505   case ARM::BI__builtin_arm_isb:
2506   case ARM::BI__builtin_arm_dbg:
2507     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 15);
2508   case ARM::BI__builtin_arm_cdp:
2509   case ARM::BI__builtin_arm_cdp2:
2510   case ARM::BI__builtin_arm_mcr:
2511   case ARM::BI__builtin_arm_mcr2:
2512   case ARM::BI__builtin_arm_mrc:
2513   case ARM::BI__builtin_arm_mrc2:
2514   case ARM::BI__builtin_arm_mcrr:
2515   case ARM::BI__builtin_arm_mcrr2:
2516   case ARM::BI__builtin_arm_mrrc:
2517   case ARM::BI__builtin_arm_mrrc2:
2518   case ARM::BI__builtin_arm_ldc:
2519   case ARM::BI__builtin_arm_ldcl:
2520   case ARM::BI__builtin_arm_ldc2:
2521   case ARM::BI__builtin_arm_ldc2l:
2522   case ARM::BI__builtin_arm_stc:
2523   case ARM::BI__builtin_arm_stcl:
2524   case ARM::BI__builtin_arm_stc2:
2525   case ARM::BI__builtin_arm_stc2l:
2526     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 15) ||
2527            CheckARMCoprocessorImmediate(TI, TheCall->getArg(0),
2528                                         /*WantCDE*/ false);
2529   }
2530 }
2531 
2532 bool Sema::CheckAArch64BuiltinFunctionCall(const TargetInfo &TI,
2533                                            unsigned BuiltinID,
2534                                            CallExpr *TheCall) {
2535   if (BuiltinID == AArch64::BI__builtin_arm_ldrex ||
2536       BuiltinID == AArch64::BI__builtin_arm_ldaex ||
2537       BuiltinID == AArch64::BI__builtin_arm_strex ||
2538       BuiltinID == AArch64::BI__builtin_arm_stlex) {
2539     return CheckARMBuiltinExclusiveCall(BuiltinID, TheCall, 128);
2540   }
2541 
2542   if (BuiltinID == AArch64::BI__builtin_arm_prefetch) {
2543     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1) ||
2544       SemaBuiltinConstantArgRange(TheCall, 2, 0, 2) ||
2545       SemaBuiltinConstantArgRange(TheCall, 3, 0, 1) ||
2546       SemaBuiltinConstantArgRange(TheCall, 4, 0, 1);
2547   }
2548 
2549   if (BuiltinID == AArch64::BI__builtin_arm_rsr64 ||
2550       BuiltinID == AArch64::BI__builtin_arm_wsr64)
2551     return SemaBuiltinARMSpecialReg(BuiltinID, TheCall, 0, 5, true);
2552 
2553   // Memory Tagging Extensions (MTE) Intrinsics
2554   if (BuiltinID == AArch64::BI__builtin_arm_irg ||
2555       BuiltinID == AArch64::BI__builtin_arm_addg ||
2556       BuiltinID == AArch64::BI__builtin_arm_gmi ||
2557       BuiltinID == AArch64::BI__builtin_arm_ldg ||
2558       BuiltinID == AArch64::BI__builtin_arm_stg ||
2559       BuiltinID == AArch64::BI__builtin_arm_subp) {
2560     return SemaBuiltinARMMemoryTaggingCall(BuiltinID, TheCall);
2561   }
2562 
2563   if (BuiltinID == AArch64::BI__builtin_arm_rsr ||
2564       BuiltinID == AArch64::BI__builtin_arm_rsrp ||
2565       BuiltinID == AArch64::BI__builtin_arm_wsr ||
2566       BuiltinID == AArch64::BI__builtin_arm_wsrp)
2567     return SemaBuiltinARMSpecialReg(BuiltinID, TheCall, 0, 5, true);
2568 
2569   // Only check the valid encoding range. Any constant in this range would be
2570   // converted to a register of the form S1_2_C3_C4_5. Let the hardware throw
2571   // an exception for incorrect registers. This matches MSVC behavior.
2572   if (BuiltinID == AArch64::BI_ReadStatusReg ||
2573       BuiltinID == AArch64::BI_WriteStatusReg)
2574     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 0x7fff);
2575 
2576   if (BuiltinID == AArch64::BI__getReg)
2577     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 31);
2578 
2579   if (CheckNeonBuiltinFunctionCall(TI, BuiltinID, TheCall))
2580     return true;
2581 
2582   if (CheckSVEBuiltinFunctionCall(BuiltinID, TheCall))
2583     return true;
2584 
2585   // For intrinsics which take an immediate value as part of the instruction,
2586   // range check them here.
2587   unsigned i = 0, l = 0, u = 0;
2588   switch (BuiltinID) {
2589   default: return false;
2590   case AArch64::BI__builtin_arm_dmb:
2591   case AArch64::BI__builtin_arm_dsb:
2592   case AArch64::BI__builtin_arm_isb: l = 0; u = 15; break;
2593   case AArch64::BI__builtin_arm_tcancel: l = 0; u = 65535; break;
2594   }
2595 
2596   return SemaBuiltinConstantArgRange(TheCall, i, l, u + l);
2597 }
2598 
2599 static bool isValidBPFPreserveFieldInfoArg(Expr *Arg) {
2600   if (Arg->getType()->getAsPlaceholderType())
2601     return false;
2602 
2603   // The first argument needs to be a record field access.
2604   // If it is an array element access, we delay decision
2605   // to BPF backend to check whether the access is a
2606   // field access or not.
2607   return (Arg->IgnoreParens()->getObjectKind() == OK_BitField ||
2608           dyn_cast<MemberExpr>(Arg->IgnoreParens()) ||
2609           dyn_cast<ArraySubscriptExpr>(Arg->IgnoreParens()));
2610 }
2611 
2612 static bool isEltOfVectorTy(ASTContext &Context, CallExpr *Call, Sema &S,
2613                             QualType VectorTy, QualType EltTy) {
2614   QualType VectorEltTy = VectorTy->castAs<VectorType>()->getElementType();
2615   if (!Context.hasSameType(VectorEltTy, EltTy)) {
2616     S.Diag(Call->getBeginLoc(), diag::err_typecheck_call_different_arg_types)
2617         << Call->getSourceRange() << VectorEltTy << EltTy;
2618     return false;
2619   }
2620   return true;
2621 }
2622 
2623 static bool isValidBPFPreserveTypeInfoArg(Expr *Arg) {
2624   QualType ArgType = Arg->getType();
2625   if (ArgType->getAsPlaceholderType())
2626     return false;
2627 
2628   // for TYPE_EXISTENCE/TYPE_SIZEOF reloc type
2629   // format:
2630   //   1. __builtin_preserve_type_info(*(<type> *)0, flag);
2631   //   2. <type> var;
2632   //      __builtin_preserve_type_info(var, flag);
2633   if (!dyn_cast<DeclRefExpr>(Arg->IgnoreParens()) &&
2634       !dyn_cast<UnaryOperator>(Arg->IgnoreParens()))
2635     return false;
2636 
2637   // Typedef type.
2638   if (ArgType->getAs<TypedefType>())
2639     return true;
2640 
2641   // Record type or Enum type.
2642   const Type *Ty = ArgType->getUnqualifiedDesugaredType();
2643   if (const auto *RT = Ty->getAs<RecordType>()) {
2644     if (!RT->getDecl()->getDeclName().isEmpty())
2645       return true;
2646   } else if (const auto *ET = Ty->getAs<EnumType>()) {
2647     if (!ET->getDecl()->getDeclName().isEmpty())
2648       return true;
2649   }
2650 
2651   return false;
2652 }
2653 
2654 static bool isValidBPFPreserveEnumValueArg(Expr *Arg) {
2655   QualType ArgType = Arg->getType();
2656   if (ArgType->getAsPlaceholderType())
2657     return false;
2658 
2659   // for ENUM_VALUE_EXISTENCE/ENUM_VALUE reloc type
2660   // format:
2661   //   __builtin_preserve_enum_value(*(<enum_type> *)<enum_value>,
2662   //                                 flag);
2663   const auto *UO = dyn_cast<UnaryOperator>(Arg->IgnoreParens());
2664   if (!UO)
2665     return false;
2666 
2667   const auto *CE = dyn_cast<CStyleCastExpr>(UO->getSubExpr());
2668   if (!CE)
2669     return false;
2670   if (CE->getCastKind() != CK_IntegralToPointer &&
2671       CE->getCastKind() != CK_NullToPointer)
2672     return false;
2673 
2674   // The integer must be from an EnumConstantDecl.
2675   const auto *DR = dyn_cast<DeclRefExpr>(CE->getSubExpr());
2676   if (!DR)
2677     return false;
2678 
2679   const EnumConstantDecl *Enumerator =
2680       dyn_cast<EnumConstantDecl>(DR->getDecl());
2681   if (!Enumerator)
2682     return false;
2683 
2684   // The type must be EnumType.
2685   const Type *Ty = ArgType->getUnqualifiedDesugaredType();
2686   const auto *ET = Ty->getAs<EnumType>();
2687   if (!ET)
2688     return false;
2689 
2690   // The enum value must be supported.
2691   for (auto *EDI : ET->getDecl()->enumerators()) {
2692     if (EDI == Enumerator)
2693       return true;
2694   }
2695 
2696   return false;
2697 }
2698 
2699 bool Sema::CheckBPFBuiltinFunctionCall(unsigned BuiltinID,
2700                                        CallExpr *TheCall) {
2701   assert((BuiltinID == BPF::BI__builtin_preserve_field_info ||
2702           BuiltinID == BPF::BI__builtin_btf_type_id ||
2703           BuiltinID == BPF::BI__builtin_preserve_type_info ||
2704           BuiltinID == BPF::BI__builtin_preserve_enum_value) &&
2705          "unexpected BPF builtin");
2706 
2707   if (checkArgCount(*this, TheCall, 2))
2708     return true;
2709 
2710   // The second argument needs to be a constant int
2711   Expr *Arg = TheCall->getArg(1);
2712   Optional<llvm::APSInt> Value = Arg->getIntegerConstantExpr(Context);
2713   diag::kind kind;
2714   if (!Value) {
2715     if (BuiltinID == BPF::BI__builtin_preserve_field_info)
2716       kind = diag::err_preserve_field_info_not_const;
2717     else if (BuiltinID == BPF::BI__builtin_btf_type_id)
2718       kind = diag::err_btf_type_id_not_const;
2719     else if (BuiltinID == BPF::BI__builtin_preserve_type_info)
2720       kind = diag::err_preserve_type_info_not_const;
2721     else
2722       kind = diag::err_preserve_enum_value_not_const;
2723     Diag(Arg->getBeginLoc(), kind) << 2 << Arg->getSourceRange();
2724     return true;
2725   }
2726 
2727   // The first argument
2728   Arg = TheCall->getArg(0);
2729   bool InvalidArg = false;
2730   bool ReturnUnsignedInt = true;
2731   if (BuiltinID == BPF::BI__builtin_preserve_field_info) {
2732     if (!isValidBPFPreserveFieldInfoArg(Arg)) {
2733       InvalidArg = true;
2734       kind = diag::err_preserve_field_info_not_field;
2735     }
2736   } else if (BuiltinID == BPF::BI__builtin_preserve_type_info) {
2737     if (!isValidBPFPreserveTypeInfoArg(Arg)) {
2738       InvalidArg = true;
2739       kind = diag::err_preserve_type_info_invalid;
2740     }
2741   } else if (BuiltinID == BPF::BI__builtin_preserve_enum_value) {
2742     if (!isValidBPFPreserveEnumValueArg(Arg)) {
2743       InvalidArg = true;
2744       kind = diag::err_preserve_enum_value_invalid;
2745     }
2746     ReturnUnsignedInt = false;
2747   } else if (BuiltinID == BPF::BI__builtin_btf_type_id) {
2748     ReturnUnsignedInt = false;
2749   }
2750 
2751   if (InvalidArg) {
2752     Diag(Arg->getBeginLoc(), kind) << 1 << Arg->getSourceRange();
2753     return true;
2754   }
2755 
2756   if (ReturnUnsignedInt)
2757     TheCall->setType(Context.UnsignedIntTy);
2758   else
2759     TheCall->setType(Context.UnsignedLongTy);
2760   return false;
2761 }
2762 
2763 bool Sema::CheckHexagonBuiltinArgument(unsigned BuiltinID, CallExpr *TheCall) {
2764   struct ArgInfo {
2765     uint8_t OpNum;
2766     bool IsSigned;
2767     uint8_t BitWidth;
2768     uint8_t Align;
2769   };
2770   struct BuiltinInfo {
2771     unsigned BuiltinID;
2772     ArgInfo Infos[2];
2773   };
2774 
2775   static BuiltinInfo Infos[] = {
2776     { Hexagon::BI__builtin_circ_ldd,                  {{ 3, true,  4,  3 }} },
2777     { Hexagon::BI__builtin_circ_ldw,                  {{ 3, true,  4,  2 }} },
2778     { Hexagon::BI__builtin_circ_ldh,                  {{ 3, true,  4,  1 }} },
2779     { Hexagon::BI__builtin_circ_lduh,                 {{ 3, true,  4,  1 }} },
2780     { Hexagon::BI__builtin_circ_ldb,                  {{ 3, true,  4,  0 }} },
2781     { Hexagon::BI__builtin_circ_ldub,                 {{ 3, true,  4,  0 }} },
2782     { Hexagon::BI__builtin_circ_std,                  {{ 3, true,  4,  3 }} },
2783     { Hexagon::BI__builtin_circ_stw,                  {{ 3, true,  4,  2 }} },
2784     { Hexagon::BI__builtin_circ_sth,                  {{ 3, true,  4,  1 }} },
2785     { Hexagon::BI__builtin_circ_sthhi,                {{ 3, true,  4,  1 }} },
2786     { Hexagon::BI__builtin_circ_stb,                  {{ 3, true,  4,  0 }} },
2787 
2788     { Hexagon::BI__builtin_HEXAGON_L2_loadrub_pci,    {{ 1, true,  4,  0 }} },
2789     { Hexagon::BI__builtin_HEXAGON_L2_loadrb_pci,     {{ 1, true,  4,  0 }} },
2790     { Hexagon::BI__builtin_HEXAGON_L2_loadruh_pci,    {{ 1, true,  4,  1 }} },
2791     { Hexagon::BI__builtin_HEXAGON_L2_loadrh_pci,     {{ 1, true,  4,  1 }} },
2792     { Hexagon::BI__builtin_HEXAGON_L2_loadri_pci,     {{ 1, true,  4,  2 }} },
2793     { Hexagon::BI__builtin_HEXAGON_L2_loadrd_pci,     {{ 1, true,  4,  3 }} },
2794     { Hexagon::BI__builtin_HEXAGON_S2_storerb_pci,    {{ 1, true,  4,  0 }} },
2795     { Hexagon::BI__builtin_HEXAGON_S2_storerh_pci,    {{ 1, true,  4,  1 }} },
2796     { Hexagon::BI__builtin_HEXAGON_S2_storerf_pci,    {{ 1, true,  4,  1 }} },
2797     { Hexagon::BI__builtin_HEXAGON_S2_storeri_pci,    {{ 1, true,  4,  2 }} },
2798     { Hexagon::BI__builtin_HEXAGON_S2_storerd_pci,    {{ 1, true,  4,  3 }} },
2799 
2800     { Hexagon::BI__builtin_HEXAGON_A2_combineii,      {{ 1, true,  8,  0 }} },
2801     { Hexagon::BI__builtin_HEXAGON_A2_tfrih,          {{ 1, false, 16, 0 }} },
2802     { Hexagon::BI__builtin_HEXAGON_A2_tfril,          {{ 1, false, 16, 0 }} },
2803     { Hexagon::BI__builtin_HEXAGON_A2_tfrpi,          {{ 0, true,  8,  0 }} },
2804     { Hexagon::BI__builtin_HEXAGON_A4_bitspliti,      {{ 1, false, 5,  0 }} },
2805     { Hexagon::BI__builtin_HEXAGON_A4_cmpbeqi,        {{ 1, false, 8,  0 }} },
2806     { Hexagon::BI__builtin_HEXAGON_A4_cmpbgti,        {{ 1, true,  8,  0 }} },
2807     { Hexagon::BI__builtin_HEXAGON_A4_cround_ri,      {{ 1, false, 5,  0 }} },
2808     { Hexagon::BI__builtin_HEXAGON_A4_round_ri,       {{ 1, false, 5,  0 }} },
2809     { Hexagon::BI__builtin_HEXAGON_A4_round_ri_sat,   {{ 1, false, 5,  0 }} },
2810     { Hexagon::BI__builtin_HEXAGON_A4_vcmpbeqi,       {{ 1, false, 8,  0 }} },
2811     { Hexagon::BI__builtin_HEXAGON_A4_vcmpbgti,       {{ 1, true,  8,  0 }} },
2812     { Hexagon::BI__builtin_HEXAGON_A4_vcmpbgtui,      {{ 1, false, 7,  0 }} },
2813     { Hexagon::BI__builtin_HEXAGON_A4_vcmpheqi,       {{ 1, true,  8,  0 }} },
2814     { Hexagon::BI__builtin_HEXAGON_A4_vcmphgti,       {{ 1, true,  8,  0 }} },
2815     { Hexagon::BI__builtin_HEXAGON_A4_vcmphgtui,      {{ 1, false, 7,  0 }} },
2816     { Hexagon::BI__builtin_HEXAGON_A4_vcmpweqi,       {{ 1, true,  8,  0 }} },
2817     { Hexagon::BI__builtin_HEXAGON_A4_vcmpwgti,       {{ 1, true,  8,  0 }} },
2818     { Hexagon::BI__builtin_HEXAGON_A4_vcmpwgtui,      {{ 1, false, 7,  0 }} },
2819     { Hexagon::BI__builtin_HEXAGON_C2_bitsclri,       {{ 1, false, 6,  0 }} },
2820     { Hexagon::BI__builtin_HEXAGON_C2_muxii,          {{ 2, true,  8,  0 }} },
2821     { Hexagon::BI__builtin_HEXAGON_C4_nbitsclri,      {{ 1, false, 6,  0 }} },
2822     { Hexagon::BI__builtin_HEXAGON_F2_dfclass,        {{ 1, false, 5,  0 }} },
2823     { Hexagon::BI__builtin_HEXAGON_F2_dfimm_n,        {{ 0, false, 10, 0 }} },
2824     { Hexagon::BI__builtin_HEXAGON_F2_dfimm_p,        {{ 0, false, 10, 0 }} },
2825     { Hexagon::BI__builtin_HEXAGON_F2_sfclass,        {{ 1, false, 5,  0 }} },
2826     { Hexagon::BI__builtin_HEXAGON_F2_sfimm_n,        {{ 0, false, 10, 0 }} },
2827     { Hexagon::BI__builtin_HEXAGON_F2_sfimm_p,        {{ 0, false, 10, 0 }} },
2828     { Hexagon::BI__builtin_HEXAGON_M4_mpyri_addi,     {{ 2, false, 6,  0 }} },
2829     { Hexagon::BI__builtin_HEXAGON_M4_mpyri_addr_u2,  {{ 1, false, 6,  2 }} },
2830     { Hexagon::BI__builtin_HEXAGON_S2_addasl_rrri,    {{ 2, false, 3,  0 }} },
2831     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_p_acc,    {{ 2, false, 6,  0 }} },
2832     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_p_and,    {{ 2, false, 6,  0 }} },
2833     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_p,        {{ 1, false, 6,  0 }} },
2834     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_p_nac,    {{ 2, false, 6,  0 }} },
2835     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_p_or,     {{ 2, false, 6,  0 }} },
2836     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_p_xacc,   {{ 2, false, 6,  0 }} },
2837     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_r_acc,    {{ 2, false, 5,  0 }} },
2838     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_r_and,    {{ 2, false, 5,  0 }} },
2839     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_r,        {{ 1, false, 5,  0 }} },
2840     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_r_nac,    {{ 2, false, 5,  0 }} },
2841     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_r_or,     {{ 2, false, 5,  0 }} },
2842     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_r_sat,    {{ 1, false, 5,  0 }} },
2843     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_r_xacc,   {{ 2, false, 5,  0 }} },
2844     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_vh,       {{ 1, false, 4,  0 }} },
2845     { Hexagon::BI__builtin_HEXAGON_S2_asl_i_vw,       {{ 1, false, 5,  0 }} },
2846     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_p_acc,    {{ 2, false, 6,  0 }} },
2847     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_p_and,    {{ 2, false, 6,  0 }} },
2848     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_p,        {{ 1, false, 6,  0 }} },
2849     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_p_nac,    {{ 2, false, 6,  0 }} },
2850     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_p_or,     {{ 2, false, 6,  0 }} },
2851     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_p_rnd_goodsyntax,
2852                                                       {{ 1, false, 6,  0 }} },
2853     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_p_rnd,    {{ 1, false, 6,  0 }} },
2854     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_r_acc,    {{ 2, false, 5,  0 }} },
2855     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_r_and,    {{ 2, false, 5,  0 }} },
2856     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_r,        {{ 1, false, 5,  0 }} },
2857     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_r_nac,    {{ 2, false, 5,  0 }} },
2858     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_r_or,     {{ 2, false, 5,  0 }} },
2859     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_r_rnd_goodsyntax,
2860                                                       {{ 1, false, 5,  0 }} },
2861     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_r_rnd,    {{ 1, false, 5,  0 }} },
2862     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_svw_trun, {{ 1, false, 5,  0 }} },
2863     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_vh,       {{ 1, false, 4,  0 }} },
2864     { Hexagon::BI__builtin_HEXAGON_S2_asr_i_vw,       {{ 1, false, 5,  0 }} },
2865     { Hexagon::BI__builtin_HEXAGON_S2_clrbit_i,       {{ 1, false, 5,  0 }} },
2866     { Hexagon::BI__builtin_HEXAGON_S2_extractu,       {{ 1, false, 5,  0 },
2867                                                        { 2, false, 5,  0 }} },
2868     { Hexagon::BI__builtin_HEXAGON_S2_extractup,      {{ 1, false, 6,  0 },
2869                                                        { 2, false, 6,  0 }} },
2870     { Hexagon::BI__builtin_HEXAGON_S2_insert,         {{ 2, false, 5,  0 },
2871                                                        { 3, false, 5,  0 }} },
2872     { Hexagon::BI__builtin_HEXAGON_S2_insertp,        {{ 2, false, 6,  0 },
2873                                                        { 3, false, 6,  0 }} },
2874     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_p_acc,    {{ 2, false, 6,  0 }} },
2875     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_p_and,    {{ 2, false, 6,  0 }} },
2876     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_p,        {{ 1, false, 6,  0 }} },
2877     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_p_nac,    {{ 2, false, 6,  0 }} },
2878     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_p_or,     {{ 2, false, 6,  0 }} },
2879     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_p_xacc,   {{ 2, false, 6,  0 }} },
2880     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_r_acc,    {{ 2, false, 5,  0 }} },
2881     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_r_and,    {{ 2, false, 5,  0 }} },
2882     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_r,        {{ 1, false, 5,  0 }} },
2883     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_r_nac,    {{ 2, false, 5,  0 }} },
2884     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_r_or,     {{ 2, false, 5,  0 }} },
2885     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_r_xacc,   {{ 2, false, 5,  0 }} },
2886     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_vh,       {{ 1, false, 4,  0 }} },
2887     { Hexagon::BI__builtin_HEXAGON_S2_lsr_i_vw,       {{ 1, false, 5,  0 }} },
2888     { Hexagon::BI__builtin_HEXAGON_S2_setbit_i,       {{ 1, false, 5,  0 }} },
2889     { Hexagon::BI__builtin_HEXAGON_S2_tableidxb_goodsyntax,
2890                                                       {{ 2, false, 4,  0 },
2891                                                        { 3, false, 5,  0 }} },
2892     { Hexagon::BI__builtin_HEXAGON_S2_tableidxd_goodsyntax,
2893                                                       {{ 2, false, 4,  0 },
2894                                                        { 3, false, 5,  0 }} },
2895     { Hexagon::BI__builtin_HEXAGON_S2_tableidxh_goodsyntax,
2896                                                       {{ 2, false, 4,  0 },
2897                                                        { 3, false, 5,  0 }} },
2898     { Hexagon::BI__builtin_HEXAGON_S2_tableidxw_goodsyntax,
2899                                                       {{ 2, false, 4,  0 },
2900                                                        { 3, false, 5,  0 }} },
2901     { Hexagon::BI__builtin_HEXAGON_S2_togglebit_i,    {{ 1, false, 5,  0 }} },
2902     { Hexagon::BI__builtin_HEXAGON_S2_tstbit_i,       {{ 1, false, 5,  0 }} },
2903     { Hexagon::BI__builtin_HEXAGON_S2_valignib,       {{ 2, false, 3,  0 }} },
2904     { Hexagon::BI__builtin_HEXAGON_S2_vspliceib,      {{ 2, false, 3,  0 }} },
2905     { Hexagon::BI__builtin_HEXAGON_S4_addi_asl_ri,    {{ 2, false, 5,  0 }} },
2906     { Hexagon::BI__builtin_HEXAGON_S4_addi_lsr_ri,    {{ 2, false, 5,  0 }} },
2907     { Hexagon::BI__builtin_HEXAGON_S4_andi_asl_ri,    {{ 2, false, 5,  0 }} },
2908     { Hexagon::BI__builtin_HEXAGON_S4_andi_lsr_ri,    {{ 2, false, 5,  0 }} },
2909     { Hexagon::BI__builtin_HEXAGON_S4_clbaddi,        {{ 1, true , 6,  0 }} },
2910     { Hexagon::BI__builtin_HEXAGON_S4_clbpaddi,       {{ 1, true,  6,  0 }} },
2911     { Hexagon::BI__builtin_HEXAGON_S4_extract,        {{ 1, false, 5,  0 },
2912                                                        { 2, false, 5,  0 }} },
2913     { Hexagon::BI__builtin_HEXAGON_S4_extractp,       {{ 1, false, 6,  0 },
2914                                                        { 2, false, 6,  0 }} },
2915     { Hexagon::BI__builtin_HEXAGON_S4_lsli,           {{ 0, true,  6,  0 }} },
2916     { Hexagon::BI__builtin_HEXAGON_S4_ntstbit_i,      {{ 1, false, 5,  0 }} },
2917     { Hexagon::BI__builtin_HEXAGON_S4_ori_asl_ri,     {{ 2, false, 5,  0 }} },
2918     { Hexagon::BI__builtin_HEXAGON_S4_ori_lsr_ri,     {{ 2, false, 5,  0 }} },
2919     { Hexagon::BI__builtin_HEXAGON_S4_subi_asl_ri,    {{ 2, false, 5,  0 }} },
2920     { Hexagon::BI__builtin_HEXAGON_S4_subi_lsr_ri,    {{ 2, false, 5,  0 }} },
2921     { Hexagon::BI__builtin_HEXAGON_S4_vrcrotate_acc,  {{ 3, false, 2,  0 }} },
2922     { Hexagon::BI__builtin_HEXAGON_S4_vrcrotate,      {{ 2, false, 2,  0 }} },
2923     { Hexagon::BI__builtin_HEXAGON_S5_asrhub_rnd_sat_goodsyntax,
2924                                                       {{ 1, false, 4,  0 }} },
2925     { Hexagon::BI__builtin_HEXAGON_S5_asrhub_sat,     {{ 1, false, 4,  0 }} },
2926     { Hexagon::BI__builtin_HEXAGON_S5_vasrhrnd_goodsyntax,
2927                                                       {{ 1, false, 4,  0 }} },
2928     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_p,        {{ 1, false, 6,  0 }} },
2929     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_p_acc,    {{ 2, false, 6,  0 }} },
2930     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_p_and,    {{ 2, false, 6,  0 }} },
2931     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_p_nac,    {{ 2, false, 6,  0 }} },
2932     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_p_or,     {{ 2, false, 6,  0 }} },
2933     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_p_xacc,   {{ 2, false, 6,  0 }} },
2934     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_r,        {{ 1, false, 5,  0 }} },
2935     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_r_acc,    {{ 2, false, 5,  0 }} },
2936     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_r_and,    {{ 2, false, 5,  0 }} },
2937     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_r_nac,    {{ 2, false, 5,  0 }} },
2938     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_r_or,     {{ 2, false, 5,  0 }} },
2939     { Hexagon::BI__builtin_HEXAGON_S6_rol_i_r_xacc,   {{ 2, false, 5,  0 }} },
2940     { Hexagon::BI__builtin_HEXAGON_V6_valignbi,       {{ 2, false, 3,  0 }} },
2941     { Hexagon::BI__builtin_HEXAGON_V6_valignbi_128B,  {{ 2, false, 3,  0 }} },
2942     { Hexagon::BI__builtin_HEXAGON_V6_vlalignbi,      {{ 2, false, 3,  0 }} },
2943     { Hexagon::BI__builtin_HEXAGON_V6_vlalignbi_128B, {{ 2, false, 3,  0 }} },
2944     { Hexagon::BI__builtin_HEXAGON_V6_vrmpybusi,      {{ 2, false, 1,  0 }} },
2945     { Hexagon::BI__builtin_HEXAGON_V6_vrmpybusi_128B, {{ 2, false, 1,  0 }} },
2946     { Hexagon::BI__builtin_HEXAGON_V6_vrmpybusi_acc,  {{ 3, false, 1,  0 }} },
2947     { Hexagon::BI__builtin_HEXAGON_V6_vrmpybusi_acc_128B,
2948                                                       {{ 3, false, 1,  0 }} },
2949     { Hexagon::BI__builtin_HEXAGON_V6_vrmpyubi,       {{ 2, false, 1,  0 }} },
2950     { Hexagon::BI__builtin_HEXAGON_V6_vrmpyubi_128B,  {{ 2, false, 1,  0 }} },
2951     { Hexagon::BI__builtin_HEXAGON_V6_vrmpyubi_acc,   {{ 3, false, 1,  0 }} },
2952     { Hexagon::BI__builtin_HEXAGON_V6_vrmpyubi_acc_128B,
2953                                                       {{ 3, false, 1,  0 }} },
2954     { Hexagon::BI__builtin_HEXAGON_V6_vrsadubi,       {{ 2, false, 1,  0 }} },
2955     { Hexagon::BI__builtin_HEXAGON_V6_vrsadubi_128B,  {{ 2, false, 1,  0 }} },
2956     { Hexagon::BI__builtin_HEXAGON_V6_vrsadubi_acc,   {{ 3, false, 1,  0 }} },
2957     { Hexagon::BI__builtin_HEXAGON_V6_vrsadubi_acc_128B,
2958                                                       {{ 3, false, 1,  0 }} },
2959   };
2960 
2961   // Use a dynamically initialized static to sort the table exactly once on
2962   // first run.
2963   static const bool SortOnce =
2964       (llvm::sort(Infos,
2965                  [](const BuiltinInfo &LHS, const BuiltinInfo &RHS) {
2966                    return LHS.BuiltinID < RHS.BuiltinID;
2967                  }),
2968        true);
2969   (void)SortOnce;
2970 
2971   const BuiltinInfo *F = llvm::partition_point(
2972       Infos, [=](const BuiltinInfo &BI) { return BI.BuiltinID < BuiltinID; });
2973   if (F == std::end(Infos) || F->BuiltinID != BuiltinID)
2974     return false;
2975 
2976   bool Error = false;
2977 
2978   for (const ArgInfo &A : F->Infos) {
2979     // Ignore empty ArgInfo elements.
2980     if (A.BitWidth == 0)
2981       continue;
2982 
2983     int32_t Min = A.IsSigned ? -(1 << (A.BitWidth - 1)) : 0;
2984     int32_t Max = (1 << (A.IsSigned ? A.BitWidth - 1 : A.BitWidth)) - 1;
2985     if (!A.Align) {
2986       Error |= SemaBuiltinConstantArgRange(TheCall, A.OpNum, Min, Max);
2987     } else {
2988       unsigned M = 1 << A.Align;
2989       Min *= M;
2990       Max *= M;
2991       Error |= SemaBuiltinConstantArgRange(TheCall, A.OpNum, Min, Max) |
2992                SemaBuiltinConstantArgMultiple(TheCall, A.OpNum, M);
2993     }
2994   }
2995   return Error;
2996 }
2997 
2998 bool Sema::CheckHexagonBuiltinFunctionCall(unsigned BuiltinID,
2999                                            CallExpr *TheCall) {
3000   return CheckHexagonBuiltinArgument(BuiltinID, TheCall);
3001 }
3002 
3003 bool Sema::CheckMipsBuiltinFunctionCall(const TargetInfo &TI,
3004                                         unsigned BuiltinID, CallExpr *TheCall) {
3005   return CheckMipsBuiltinCpu(TI, BuiltinID, TheCall) ||
3006          CheckMipsBuiltinArgument(BuiltinID, TheCall);
3007 }
3008 
3009 bool Sema::CheckMipsBuiltinCpu(const TargetInfo &TI, unsigned BuiltinID,
3010                                CallExpr *TheCall) {
3011 
3012   if (Mips::BI__builtin_mips_addu_qb <= BuiltinID &&
3013       BuiltinID <= Mips::BI__builtin_mips_lwx) {
3014     if (!TI.hasFeature("dsp"))
3015       return Diag(TheCall->getBeginLoc(), diag::err_mips_builtin_requires_dsp);
3016   }
3017 
3018   if (Mips::BI__builtin_mips_absq_s_qb <= BuiltinID &&
3019       BuiltinID <= Mips::BI__builtin_mips_subuh_r_qb) {
3020     if (!TI.hasFeature("dspr2"))
3021       return Diag(TheCall->getBeginLoc(),
3022                   diag::err_mips_builtin_requires_dspr2);
3023   }
3024 
3025   if (Mips::BI__builtin_msa_add_a_b <= BuiltinID &&
3026       BuiltinID <= Mips::BI__builtin_msa_xori_b) {
3027     if (!TI.hasFeature("msa"))
3028       return Diag(TheCall->getBeginLoc(), diag::err_mips_builtin_requires_msa);
3029   }
3030 
3031   return false;
3032 }
3033 
3034 // CheckMipsBuiltinArgument - Checks the constant value passed to the
3035 // intrinsic is correct. The switch statement is ordered by DSP, MSA. The
3036 // ordering for DSP is unspecified. MSA is ordered by the data format used
3037 // by the underlying instruction i.e., df/m, df/n and then by size.
3038 //
3039 // FIXME: The size tests here should instead be tablegen'd along with the
3040 //        definitions from include/clang/Basic/BuiltinsMips.def.
3041 // FIXME: GCC is strict on signedness for some of these intrinsics, we should
3042 //        be too.
3043 bool Sema::CheckMipsBuiltinArgument(unsigned BuiltinID, CallExpr *TheCall) {
3044   unsigned i = 0, l = 0, u = 0, m = 0;
3045   switch (BuiltinID) {
3046   default: return false;
3047   case Mips::BI__builtin_mips_wrdsp: i = 1; l = 0; u = 63; break;
3048   case Mips::BI__builtin_mips_rddsp: i = 0; l = 0; u = 63; break;
3049   case Mips::BI__builtin_mips_append: i = 2; l = 0; u = 31; break;
3050   case Mips::BI__builtin_mips_balign: i = 2; l = 0; u = 3; break;
3051   case Mips::BI__builtin_mips_precr_sra_ph_w: i = 2; l = 0; u = 31; break;
3052   case Mips::BI__builtin_mips_precr_sra_r_ph_w: i = 2; l = 0; u = 31; break;
3053   case Mips::BI__builtin_mips_prepend: i = 2; l = 0; u = 31; break;
3054   // MSA intrinsics. Instructions (which the intrinsics maps to) which use the
3055   // df/m field.
3056   // These intrinsics take an unsigned 3 bit immediate.
3057   case Mips::BI__builtin_msa_bclri_b:
3058   case Mips::BI__builtin_msa_bnegi_b:
3059   case Mips::BI__builtin_msa_bseti_b:
3060   case Mips::BI__builtin_msa_sat_s_b:
3061   case Mips::BI__builtin_msa_sat_u_b:
3062   case Mips::BI__builtin_msa_slli_b:
3063   case Mips::BI__builtin_msa_srai_b:
3064   case Mips::BI__builtin_msa_srari_b:
3065   case Mips::BI__builtin_msa_srli_b:
3066   case Mips::BI__builtin_msa_srlri_b: i = 1; l = 0; u = 7; break;
3067   case Mips::BI__builtin_msa_binsli_b:
3068   case Mips::BI__builtin_msa_binsri_b: i = 2; l = 0; u = 7; break;
3069   // These intrinsics take an unsigned 4 bit immediate.
3070   case Mips::BI__builtin_msa_bclri_h:
3071   case Mips::BI__builtin_msa_bnegi_h:
3072   case Mips::BI__builtin_msa_bseti_h:
3073   case Mips::BI__builtin_msa_sat_s_h:
3074   case Mips::BI__builtin_msa_sat_u_h:
3075   case Mips::BI__builtin_msa_slli_h:
3076   case Mips::BI__builtin_msa_srai_h:
3077   case Mips::BI__builtin_msa_srari_h:
3078   case Mips::BI__builtin_msa_srli_h:
3079   case Mips::BI__builtin_msa_srlri_h: i = 1; l = 0; u = 15; break;
3080   case Mips::BI__builtin_msa_binsli_h:
3081   case Mips::BI__builtin_msa_binsri_h: i = 2; l = 0; u = 15; break;
3082   // These intrinsics take an unsigned 5 bit immediate.
3083   // The first block of intrinsics actually have an unsigned 5 bit field,
3084   // not a df/n field.
3085   case Mips::BI__builtin_msa_cfcmsa:
3086   case Mips::BI__builtin_msa_ctcmsa: i = 0; l = 0; u = 31; break;
3087   case Mips::BI__builtin_msa_clei_u_b:
3088   case Mips::BI__builtin_msa_clei_u_h:
3089   case Mips::BI__builtin_msa_clei_u_w:
3090   case Mips::BI__builtin_msa_clei_u_d:
3091   case Mips::BI__builtin_msa_clti_u_b:
3092   case Mips::BI__builtin_msa_clti_u_h:
3093   case Mips::BI__builtin_msa_clti_u_w:
3094   case Mips::BI__builtin_msa_clti_u_d:
3095   case Mips::BI__builtin_msa_maxi_u_b:
3096   case Mips::BI__builtin_msa_maxi_u_h:
3097   case Mips::BI__builtin_msa_maxi_u_w:
3098   case Mips::BI__builtin_msa_maxi_u_d:
3099   case Mips::BI__builtin_msa_mini_u_b:
3100   case Mips::BI__builtin_msa_mini_u_h:
3101   case Mips::BI__builtin_msa_mini_u_w:
3102   case Mips::BI__builtin_msa_mini_u_d:
3103   case Mips::BI__builtin_msa_addvi_b:
3104   case Mips::BI__builtin_msa_addvi_h:
3105   case Mips::BI__builtin_msa_addvi_w:
3106   case Mips::BI__builtin_msa_addvi_d:
3107   case Mips::BI__builtin_msa_bclri_w:
3108   case Mips::BI__builtin_msa_bnegi_w:
3109   case Mips::BI__builtin_msa_bseti_w:
3110   case Mips::BI__builtin_msa_sat_s_w:
3111   case Mips::BI__builtin_msa_sat_u_w:
3112   case Mips::BI__builtin_msa_slli_w:
3113   case Mips::BI__builtin_msa_srai_w:
3114   case Mips::BI__builtin_msa_srari_w:
3115   case Mips::BI__builtin_msa_srli_w:
3116   case Mips::BI__builtin_msa_srlri_w:
3117   case Mips::BI__builtin_msa_subvi_b:
3118   case Mips::BI__builtin_msa_subvi_h:
3119   case Mips::BI__builtin_msa_subvi_w:
3120   case Mips::BI__builtin_msa_subvi_d: i = 1; l = 0; u = 31; break;
3121   case Mips::BI__builtin_msa_binsli_w:
3122   case Mips::BI__builtin_msa_binsri_w: i = 2; l = 0; u = 31; break;
3123   // These intrinsics take an unsigned 6 bit immediate.
3124   case Mips::BI__builtin_msa_bclri_d:
3125   case Mips::BI__builtin_msa_bnegi_d:
3126   case Mips::BI__builtin_msa_bseti_d:
3127   case Mips::BI__builtin_msa_sat_s_d:
3128   case Mips::BI__builtin_msa_sat_u_d:
3129   case Mips::BI__builtin_msa_slli_d:
3130   case Mips::BI__builtin_msa_srai_d:
3131   case Mips::BI__builtin_msa_srari_d:
3132   case Mips::BI__builtin_msa_srli_d:
3133   case Mips::BI__builtin_msa_srlri_d: i = 1; l = 0; u = 63; break;
3134   case Mips::BI__builtin_msa_binsli_d:
3135   case Mips::BI__builtin_msa_binsri_d: i = 2; l = 0; u = 63; break;
3136   // These intrinsics take a signed 5 bit immediate.
3137   case Mips::BI__builtin_msa_ceqi_b:
3138   case Mips::BI__builtin_msa_ceqi_h:
3139   case Mips::BI__builtin_msa_ceqi_w:
3140   case Mips::BI__builtin_msa_ceqi_d:
3141   case Mips::BI__builtin_msa_clti_s_b:
3142   case Mips::BI__builtin_msa_clti_s_h:
3143   case Mips::BI__builtin_msa_clti_s_w:
3144   case Mips::BI__builtin_msa_clti_s_d:
3145   case Mips::BI__builtin_msa_clei_s_b:
3146   case Mips::BI__builtin_msa_clei_s_h:
3147   case Mips::BI__builtin_msa_clei_s_w:
3148   case Mips::BI__builtin_msa_clei_s_d:
3149   case Mips::BI__builtin_msa_maxi_s_b:
3150   case Mips::BI__builtin_msa_maxi_s_h:
3151   case Mips::BI__builtin_msa_maxi_s_w:
3152   case Mips::BI__builtin_msa_maxi_s_d:
3153   case Mips::BI__builtin_msa_mini_s_b:
3154   case Mips::BI__builtin_msa_mini_s_h:
3155   case Mips::BI__builtin_msa_mini_s_w:
3156   case Mips::BI__builtin_msa_mini_s_d: i = 1; l = -16; u = 15; break;
3157   // These intrinsics take an unsigned 8 bit immediate.
3158   case Mips::BI__builtin_msa_andi_b:
3159   case Mips::BI__builtin_msa_nori_b:
3160   case Mips::BI__builtin_msa_ori_b:
3161   case Mips::BI__builtin_msa_shf_b:
3162   case Mips::BI__builtin_msa_shf_h:
3163   case Mips::BI__builtin_msa_shf_w:
3164   case Mips::BI__builtin_msa_xori_b: i = 1; l = 0; u = 255; break;
3165   case Mips::BI__builtin_msa_bseli_b:
3166   case Mips::BI__builtin_msa_bmnzi_b:
3167   case Mips::BI__builtin_msa_bmzi_b: i = 2; l = 0; u = 255; break;
3168   // df/n format
3169   // These intrinsics take an unsigned 4 bit immediate.
3170   case Mips::BI__builtin_msa_copy_s_b:
3171   case Mips::BI__builtin_msa_copy_u_b:
3172   case Mips::BI__builtin_msa_insve_b:
3173   case Mips::BI__builtin_msa_splati_b: i = 1; l = 0; u = 15; break;
3174   case Mips::BI__builtin_msa_sldi_b: i = 2; l = 0; u = 15; break;
3175   // These intrinsics take an unsigned 3 bit immediate.
3176   case Mips::BI__builtin_msa_copy_s_h:
3177   case Mips::BI__builtin_msa_copy_u_h:
3178   case Mips::BI__builtin_msa_insve_h:
3179   case Mips::BI__builtin_msa_splati_h: i = 1; l = 0; u = 7; break;
3180   case Mips::BI__builtin_msa_sldi_h: i = 2; l = 0; u = 7; break;
3181   // These intrinsics take an unsigned 2 bit immediate.
3182   case Mips::BI__builtin_msa_copy_s_w:
3183   case Mips::BI__builtin_msa_copy_u_w:
3184   case Mips::BI__builtin_msa_insve_w:
3185   case Mips::BI__builtin_msa_splati_w: i = 1; l = 0; u = 3; break;
3186   case Mips::BI__builtin_msa_sldi_w: i = 2; l = 0; u = 3; break;
3187   // These intrinsics take an unsigned 1 bit immediate.
3188   case Mips::BI__builtin_msa_copy_s_d:
3189   case Mips::BI__builtin_msa_copy_u_d:
3190   case Mips::BI__builtin_msa_insve_d:
3191   case Mips::BI__builtin_msa_splati_d: i = 1; l = 0; u = 1; break;
3192   case Mips::BI__builtin_msa_sldi_d: i = 2; l = 0; u = 1; break;
3193   // Memory offsets and immediate loads.
3194   // These intrinsics take a signed 10 bit immediate.
3195   case Mips::BI__builtin_msa_ldi_b: i = 0; l = -128; u = 255; break;
3196   case Mips::BI__builtin_msa_ldi_h:
3197   case Mips::BI__builtin_msa_ldi_w:
3198   case Mips::BI__builtin_msa_ldi_d: i = 0; l = -512; u = 511; break;
3199   case Mips::BI__builtin_msa_ld_b: i = 1; l = -512; u = 511; m = 1; break;
3200   case Mips::BI__builtin_msa_ld_h: i = 1; l = -1024; u = 1022; m = 2; break;
3201   case Mips::BI__builtin_msa_ld_w: i = 1; l = -2048; u = 2044; m = 4; break;
3202   case Mips::BI__builtin_msa_ld_d: i = 1; l = -4096; u = 4088; m = 8; break;
3203   case Mips::BI__builtin_msa_ldr_d: i = 1; l = -4096; u = 4088; m = 8; break;
3204   case Mips::BI__builtin_msa_ldr_w: i = 1; l = -2048; u = 2044; m = 4; break;
3205   case Mips::BI__builtin_msa_st_b: i = 2; l = -512; u = 511; m = 1; break;
3206   case Mips::BI__builtin_msa_st_h: i = 2; l = -1024; u = 1022; m = 2; break;
3207   case Mips::BI__builtin_msa_st_w: i = 2; l = -2048; u = 2044; m = 4; break;
3208   case Mips::BI__builtin_msa_st_d: i = 2; l = -4096; u = 4088; m = 8; break;
3209   case Mips::BI__builtin_msa_str_d: i = 2; l = -4096; u = 4088; m = 8; break;
3210   case Mips::BI__builtin_msa_str_w: i = 2; l = -2048; u = 2044; m = 4; break;
3211   }
3212 
3213   if (!m)
3214     return SemaBuiltinConstantArgRange(TheCall, i, l, u);
3215 
3216   return SemaBuiltinConstantArgRange(TheCall, i, l, u) ||
3217          SemaBuiltinConstantArgMultiple(TheCall, i, m);
3218 }
3219 
3220 /// DecodePPCMMATypeFromStr - This decodes one PPC MMA type descriptor from Str,
3221 /// advancing the pointer over the consumed characters. The decoded type is
3222 /// returned. If the decoded type represents a constant integer with a
3223 /// constraint on its value then Mask is set to that value. The type descriptors
3224 /// used in Str are specific to PPC MMA builtins and are documented in the file
3225 /// defining the PPC builtins.
3226 static QualType DecodePPCMMATypeFromStr(ASTContext &Context, const char *&Str,
3227                                         unsigned &Mask) {
3228   bool RequireICE = false;
3229   ASTContext::GetBuiltinTypeError Error = ASTContext::GE_None;
3230   switch (*Str++) {
3231   case 'V':
3232     return Context.getVectorType(Context.UnsignedCharTy, 16,
3233                                  VectorType::VectorKind::AltiVecVector);
3234   case 'i': {
3235     char *End;
3236     unsigned size = strtoul(Str, &End, 10);
3237     assert(End != Str && "Missing constant parameter constraint");
3238     Str = End;
3239     Mask = size;
3240     return Context.IntTy;
3241   }
3242   case 'W': {
3243     char *End;
3244     unsigned size = strtoul(Str, &End, 10);
3245     assert(End != Str && "Missing PowerPC MMA type size");
3246     Str = End;
3247     QualType Type;
3248     switch (size) {
3249   #define PPC_VECTOR_TYPE(typeName, Id, size) \
3250     case size: Type = Context.Id##Ty; break;
3251   #include "clang/Basic/PPCTypes.def"
3252     default: llvm_unreachable("Invalid PowerPC MMA vector type");
3253     }
3254     bool CheckVectorArgs = false;
3255     while (!CheckVectorArgs) {
3256       switch (*Str++) {
3257       case '*':
3258         Type = Context.getPointerType(Type);
3259         break;
3260       case 'C':
3261         Type = Type.withConst();
3262         break;
3263       default:
3264         CheckVectorArgs = true;
3265         --Str;
3266         break;
3267       }
3268     }
3269     return Type;
3270   }
3271   default:
3272     return Context.DecodeTypeStr(--Str, Context, Error, RequireICE, true);
3273   }
3274 }
3275 
3276 static bool isPPC_64Builtin(unsigned BuiltinID) {
3277   // These builtins only work on PPC 64bit targets.
3278   switch (BuiltinID) {
3279   case PPC::BI__builtin_divde:
3280   case PPC::BI__builtin_divdeu:
3281   case PPC::BI__builtin_bpermd:
3282   case PPC::BI__builtin_ppc_ldarx:
3283   case PPC::BI__builtin_ppc_stdcx:
3284   case PPC::BI__builtin_ppc_tdw:
3285   case PPC::BI__builtin_ppc_trapd:
3286   case PPC::BI__builtin_ppc_cmpeqb:
3287   case PPC::BI__builtin_ppc_setb:
3288   case PPC::BI__builtin_ppc_mulhd:
3289   case PPC::BI__builtin_ppc_mulhdu:
3290   case PPC::BI__builtin_ppc_maddhd:
3291   case PPC::BI__builtin_ppc_maddhdu:
3292   case PPC::BI__builtin_ppc_maddld:
3293   case PPC::BI__builtin_ppc_load8r:
3294   case PPC::BI__builtin_ppc_store8r:
3295   case PPC::BI__builtin_ppc_insert_exp:
3296   case PPC::BI__builtin_ppc_extract_sig:
3297   case PPC::BI__builtin_ppc_addex:
3298     return true;
3299   }
3300   return false;
3301 }
3302 
3303 static bool SemaFeatureCheck(Sema &S, CallExpr *TheCall,
3304                              StringRef FeatureToCheck, unsigned DiagID,
3305                              StringRef DiagArg = "") {
3306   if (S.Context.getTargetInfo().hasFeature(FeatureToCheck))
3307     return false;
3308 
3309   if (DiagArg.empty())
3310     S.Diag(TheCall->getBeginLoc(), DiagID) << TheCall->getSourceRange();
3311   else
3312     S.Diag(TheCall->getBeginLoc(), DiagID)
3313         << DiagArg << TheCall->getSourceRange();
3314 
3315   return true;
3316 }
3317 
3318 /// Returns true if the argument consists of one contiguous run of 1s with any
3319 /// number of 0s on either side. The 1s are allowed to wrap from LSB to MSB, so
3320 /// 0x000FFF0, 0x0000FFFF, 0xFF0000FF, 0x0 are all runs. 0x0F0F0000 is not,
3321 /// since all 1s are not contiguous.
3322 bool Sema::SemaValueIsRunOfOnes(CallExpr *TheCall, unsigned ArgNum) {
3323   llvm::APSInt Result;
3324   // We can't check the value of a dependent argument.
3325   Expr *Arg = TheCall->getArg(ArgNum);
3326   if (Arg->isTypeDependent() || Arg->isValueDependent())
3327     return false;
3328 
3329   // Check constant-ness first.
3330   if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
3331     return true;
3332 
3333   // Check contiguous run of 1s, 0xFF0000FF is also a run of 1s.
3334   if (Result.isShiftedMask() || (~Result).isShiftedMask())
3335     return false;
3336 
3337   return Diag(TheCall->getBeginLoc(),
3338               diag::err_argument_not_contiguous_bit_field)
3339          << ArgNum << Arg->getSourceRange();
3340 }
3341 
3342 bool Sema::CheckPPCBuiltinFunctionCall(const TargetInfo &TI, unsigned BuiltinID,
3343                                        CallExpr *TheCall) {
3344   unsigned i = 0, l = 0, u = 0;
3345   bool IsTarget64Bit = TI.getTypeWidth(TI.getIntPtrType()) == 64;
3346   llvm::APSInt Result;
3347 
3348   if (isPPC_64Builtin(BuiltinID) && !IsTarget64Bit)
3349     return Diag(TheCall->getBeginLoc(), diag::err_64_bit_builtin_32_bit_tgt)
3350            << TheCall->getSourceRange();
3351 
3352   switch (BuiltinID) {
3353   default: return false;
3354   case PPC::BI__builtin_altivec_crypto_vshasigmaw:
3355   case PPC::BI__builtin_altivec_crypto_vshasigmad:
3356     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1) ||
3357            SemaBuiltinConstantArgRange(TheCall, 2, 0, 15);
3358   case PPC::BI__builtin_altivec_dss:
3359     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 3);
3360   case PPC::BI__builtin_tbegin:
3361   case PPC::BI__builtin_tend: i = 0; l = 0; u = 1; break;
3362   case PPC::BI__builtin_tsr: i = 0; l = 0; u = 7; break;
3363   case PPC::BI__builtin_tabortwc:
3364   case PPC::BI__builtin_tabortdc: i = 0; l = 0; u = 31; break;
3365   case PPC::BI__builtin_tabortwci:
3366   case PPC::BI__builtin_tabortdci:
3367     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 31) ||
3368            SemaBuiltinConstantArgRange(TheCall, 2, 0, 31);
3369   case PPC::BI__builtin_altivec_dst:
3370   case PPC::BI__builtin_altivec_dstt:
3371   case PPC::BI__builtin_altivec_dstst:
3372   case PPC::BI__builtin_altivec_dststt:
3373     return SemaBuiltinConstantArgRange(TheCall, 2, 0, 3);
3374   case PPC::BI__builtin_vsx_xxpermdi:
3375   case PPC::BI__builtin_vsx_xxsldwi:
3376     return SemaBuiltinVSX(TheCall);
3377   case PPC::BI__builtin_divwe:
3378   case PPC::BI__builtin_divweu:
3379   case PPC::BI__builtin_divde:
3380   case PPC::BI__builtin_divdeu:
3381     return SemaFeatureCheck(*this, TheCall, "extdiv",
3382                             diag::err_ppc_builtin_only_on_arch, "7");
3383   case PPC::BI__builtin_bpermd:
3384     return SemaFeatureCheck(*this, TheCall, "bpermd",
3385                             diag::err_ppc_builtin_only_on_arch, "7");
3386   case PPC::BI__builtin_unpack_vector_int128:
3387     return SemaFeatureCheck(*this, TheCall, "vsx",
3388                             diag::err_ppc_builtin_only_on_arch, "7") ||
3389            SemaBuiltinConstantArgRange(TheCall, 1, 0, 1);
3390   case PPC::BI__builtin_pack_vector_int128:
3391     return SemaFeatureCheck(*this, TheCall, "vsx",
3392                             diag::err_ppc_builtin_only_on_arch, "7");
3393   case PPC::BI__builtin_altivec_vgnb:
3394      return SemaBuiltinConstantArgRange(TheCall, 1, 2, 7);
3395   case PPC::BI__builtin_altivec_vec_replace_elt:
3396   case PPC::BI__builtin_altivec_vec_replace_unaligned: {
3397     QualType VecTy = TheCall->getArg(0)->getType();
3398     QualType EltTy = TheCall->getArg(1)->getType();
3399     unsigned Width = Context.getIntWidth(EltTy);
3400     return SemaBuiltinConstantArgRange(TheCall, 2, 0, Width == 32 ? 12 : 8) ||
3401            !isEltOfVectorTy(Context, TheCall, *this, VecTy, EltTy);
3402   }
3403   case PPC::BI__builtin_vsx_xxeval:
3404      return SemaBuiltinConstantArgRange(TheCall, 3, 0, 255);
3405   case PPC::BI__builtin_altivec_vsldbi:
3406      return SemaBuiltinConstantArgRange(TheCall, 2, 0, 7);
3407   case PPC::BI__builtin_altivec_vsrdbi:
3408      return SemaBuiltinConstantArgRange(TheCall, 2, 0, 7);
3409   case PPC::BI__builtin_vsx_xxpermx:
3410      return SemaBuiltinConstantArgRange(TheCall, 3, 0, 7);
3411   case PPC::BI__builtin_ppc_tw:
3412   case PPC::BI__builtin_ppc_tdw:
3413     return SemaBuiltinConstantArgRange(TheCall, 2, 1, 31);
3414   case PPC::BI__builtin_ppc_cmpeqb:
3415   case PPC::BI__builtin_ppc_setb:
3416   case PPC::BI__builtin_ppc_maddhd:
3417   case PPC::BI__builtin_ppc_maddhdu:
3418   case PPC::BI__builtin_ppc_maddld:
3419     return SemaFeatureCheck(*this, TheCall, "isa-v30-instructions",
3420                             diag::err_ppc_builtin_only_on_arch, "9");
3421   case PPC::BI__builtin_ppc_cmprb:
3422     return SemaFeatureCheck(*this, TheCall, "isa-v30-instructions",
3423                             diag::err_ppc_builtin_only_on_arch, "9") ||
3424            SemaBuiltinConstantArgRange(TheCall, 0, 0, 1);
3425   // For __rlwnm, __rlwimi and __rldimi, the last parameter mask must
3426   // be a constant that represents a contiguous bit field.
3427   case PPC::BI__builtin_ppc_rlwnm:
3428     return SemaBuiltinConstantArg(TheCall, 1, Result) ||
3429            SemaValueIsRunOfOnes(TheCall, 2);
3430   case PPC::BI__builtin_ppc_rlwimi:
3431   case PPC::BI__builtin_ppc_rldimi:
3432     return SemaBuiltinConstantArg(TheCall, 2, Result) ||
3433            SemaValueIsRunOfOnes(TheCall, 3);
3434   case PPC::BI__builtin_ppc_extract_exp:
3435   case PPC::BI__builtin_ppc_extract_sig:
3436   case PPC::BI__builtin_ppc_insert_exp:
3437     return SemaFeatureCheck(*this, TheCall, "power9-vector",
3438                             diag::err_ppc_builtin_only_on_arch, "9");
3439   case PPC::BI__builtin_ppc_addex: {
3440     if (SemaFeatureCheck(*this, TheCall, "isa-v30-instructions",
3441                          diag::err_ppc_builtin_only_on_arch, "9") ||
3442         SemaBuiltinConstantArgRange(TheCall, 2, 0, 3))
3443       return true;
3444     // Output warning for reserved values 1 to 3.
3445     int ArgValue =
3446         TheCall->getArg(2)->getIntegerConstantExpr(Context)->getSExtValue();
3447     if (ArgValue != 0)
3448       Diag(TheCall->getBeginLoc(), diag::warn_argument_undefined_behaviour)
3449           << ArgValue;
3450     return false;
3451   }
3452   case PPC::BI__builtin_ppc_mtfsb0:
3453   case PPC::BI__builtin_ppc_mtfsb1:
3454     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 31);
3455   case PPC::BI__builtin_ppc_mtfsf:
3456     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 255);
3457   case PPC::BI__builtin_ppc_mtfsfi:
3458     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 7) ||
3459            SemaBuiltinConstantArgRange(TheCall, 1, 0, 15);
3460   case PPC::BI__builtin_ppc_alignx:
3461     return SemaBuiltinConstantArgPower2(TheCall, 0);
3462   case PPC::BI__builtin_ppc_rdlam:
3463     return SemaValueIsRunOfOnes(TheCall, 2);
3464   case PPC::BI__builtin_ppc_icbt:
3465   case PPC::BI__builtin_ppc_sthcx:
3466   case PPC::BI__builtin_ppc_stbcx:
3467   case PPC::BI__builtin_ppc_lharx:
3468   case PPC::BI__builtin_ppc_lbarx:
3469     return SemaFeatureCheck(*this, TheCall, "isa-v207-instructions",
3470                             diag::err_ppc_builtin_only_on_arch, "8");
3471   case PPC::BI__builtin_vsx_ldrmb:
3472   case PPC::BI__builtin_vsx_strmb:
3473     return SemaFeatureCheck(*this, TheCall, "isa-v207-instructions",
3474                             diag::err_ppc_builtin_only_on_arch, "8") ||
3475            SemaBuiltinConstantArgRange(TheCall, 1, 1, 16);
3476 #define CUSTOM_BUILTIN(Name, Intr, Types, Acc) \
3477   case PPC::BI__builtin_##Name: \
3478     return SemaBuiltinPPCMMACall(TheCall, Types);
3479 #include "clang/Basic/BuiltinsPPC.def"
3480   }
3481   return SemaBuiltinConstantArgRange(TheCall, i, l, u);
3482 }
3483 
3484 // Check if the given type is a non-pointer PPC MMA type. This function is used
3485 // in Sema to prevent invalid uses of restricted PPC MMA types.
3486 bool Sema::CheckPPCMMAType(QualType Type, SourceLocation TypeLoc) {
3487   if (Type->isPointerType() || Type->isArrayType())
3488     return false;
3489 
3490   QualType CoreType = Type.getCanonicalType().getUnqualifiedType();
3491 #define PPC_VECTOR_TYPE(Name, Id, Size) || CoreType == Context.Id##Ty
3492   if (false
3493 #include "clang/Basic/PPCTypes.def"
3494      ) {
3495     Diag(TypeLoc, diag::err_ppc_invalid_use_mma_type);
3496     return true;
3497   }
3498   return false;
3499 }
3500 
3501 bool Sema::CheckAMDGCNBuiltinFunctionCall(unsigned BuiltinID,
3502                                           CallExpr *TheCall) {
3503   // position of memory order and scope arguments in the builtin
3504   unsigned OrderIndex, ScopeIndex;
3505   switch (BuiltinID) {
3506   case AMDGPU::BI__builtin_amdgcn_atomic_inc32:
3507   case AMDGPU::BI__builtin_amdgcn_atomic_inc64:
3508   case AMDGPU::BI__builtin_amdgcn_atomic_dec32:
3509   case AMDGPU::BI__builtin_amdgcn_atomic_dec64:
3510     OrderIndex = 2;
3511     ScopeIndex = 3;
3512     break;
3513   case AMDGPU::BI__builtin_amdgcn_fence:
3514     OrderIndex = 0;
3515     ScopeIndex = 1;
3516     break;
3517   default:
3518     return false;
3519   }
3520 
3521   ExprResult Arg = TheCall->getArg(OrderIndex);
3522   auto ArgExpr = Arg.get();
3523   Expr::EvalResult ArgResult;
3524 
3525   if (!ArgExpr->EvaluateAsInt(ArgResult, Context))
3526     return Diag(ArgExpr->getExprLoc(), diag::err_typecheck_expect_int)
3527            << ArgExpr->getType();
3528   auto Ord = ArgResult.Val.getInt().getZExtValue();
3529 
3530   // Check valididty of memory ordering as per C11 / C++11's memody model.
3531   // Only fence needs check. Atomic dec/inc allow all memory orders.
3532   if (!llvm::isValidAtomicOrderingCABI(Ord))
3533     return Diag(ArgExpr->getBeginLoc(),
3534                 diag::warn_atomic_op_has_invalid_memory_order)
3535            << ArgExpr->getSourceRange();
3536   switch (static_cast<llvm::AtomicOrderingCABI>(Ord)) {
3537   case llvm::AtomicOrderingCABI::relaxed:
3538   case llvm::AtomicOrderingCABI::consume:
3539     if (BuiltinID == AMDGPU::BI__builtin_amdgcn_fence)
3540       return Diag(ArgExpr->getBeginLoc(),
3541                   diag::warn_atomic_op_has_invalid_memory_order)
3542              << ArgExpr->getSourceRange();
3543     break;
3544   case llvm::AtomicOrderingCABI::acquire:
3545   case llvm::AtomicOrderingCABI::release:
3546   case llvm::AtomicOrderingCABI::acq_rel:
3547   case llvm::AtomicOrderingCABI::seq_cst:
3548     break;
3549   }
3550 
3551   Arg = TheCall->getArg(ScopeIndex);
3552   ArgExpr = Arg.get();
3553   Expr::EvalResult ArgResult1;
3554   // Check that sync scope is a constant literal
3555   if (!ArgExpr->EvaluateAsConstantExpr(ArgResult1, Context))
3556     return Diag(ArgExpr->getExprLoc(), diag::err_expr_not_string_literal)
3557            << ArgExpr->getType();
3558 
3559   return false;
3560 }
3561 
3562 bool Sema::CheckRISCVLMUL(CallExpr *TheCall, unsigned ArgNum) {
3563   llvm::APSInt Result;
3564 
3565   // We can't check the value of a dependent argument.
3566   Expr *Arg = TheCall->getArg(ArgNum);
3567   if (Arg->isTypeDependent() || Arg->isValueDependent())
3568     return false;
3569 
3570   // Check constant-ness first.
3571   if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
3572     return true;
3573 
3574   int64_t Val = Result.getSExtValue();
3575   if ((Val >= 0 && Val <= 3) || (Val >= 5 && Val <= 7))
3576     return false;
3577 
3578   return Diag(TheCall->getBeginLoc(), diag::err_riscv_builtin_invalid_lmul)
3579          << Arg->getSourceRange();
3580 }
3581 
3582 bool Sema::CheckRISCVBuiltinFunctionCall(const TargetInfo &TI,
3583                                          unsigned BuiltinID,
3584                                          CallExpr *TheCall) {
3585   // CodeGenFunction can also detect this, but this gives a better error
3586   // message.
3587   bool FeatureMissing = false;
3588   SmallVector<StringRef> ReqFeatures;
3589   StringRef Features = Context.BuiltinInfo.getRequiredFeatures(BuiltinID);
3590   Features.split(ReqFeatures, ',');
3591 
3592   // Check if each required feature is included
3593   for (StringRef F : ReqFeatures) {
3594     if (TI.hasFeature(F))
3595       continue;
3596 
3597     // If the feature is 64bit, alter the string so it will print better in
3598     // the diagnostic.
3599     if (F == "64bit")
3600       F = "RV64";
3601 
3602     // Convert features like "zbr" and "experimental-zbr" to "Zbr".
3603     F.consume_front("experimental-");
3604     std::string FeatureStr = F.str();
3605     FeatureStr[0] = std::toupper(FeatureStr[0]);
3606 
3607     // Error message
3608     FeatureMissing = true;
3609     Diag(TheCall->getBeginLoc(), diag::err_riscv_builtin_requires_extension)
3610         << TheCall->getSourceRange() << StringRef(FeatureStr);
3611   }
3612 
3613   if (FeatureMissing)
3614     return true;
3615 
3616   switch (BuiltinID) {
3617   case RISCV::BI__builtin_rvv_vsetvli:
3618     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 3) ||
3619            CheckRISCVLMUL(TheCall, 2);
3620   case RISCV::BI__builtin_rvv_vsetvlimax:
3621     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 3) ||
3622            CheckRISCVLMUL(TheCall, 1);
3623   case RISCV::BI__builtin_rvv_vget_v_i8m2_i8m1:
3624   case RISCV::BI__builtin_rvv_vget_v_i16m2_i16m1:
3625   case RISCV::BI__builtin_rvv_vget_v_i32m2_i32m1:
3626   case RISCV::BI__builtin_rvv_vget_v_i64m2_i64m1:
3627   case RISCV::BI__builtin_rvv_vget_v_f32m2_f32m1:
3628   case RISCV::BI__builtin_rvv_vget_v_f64m2_f64m1:
3629   case RISCV::BI__builtin_rvv_vget_v_u8m2_u8m1:
3630   case RISCV::BI__builtin_rvv_vget_v_u16m2_u16m1:
3631   case RISCV::BI__builtin_rvv_vget_v_u32m2_u32m1:
3632   case RISCV::BI__builtin_rvv_vget_v_u64m2_u64m1:
3633   case RISCV::BI__builtin_rvv_vget_v_i8m4_i8m2:
3634   case RISCV::BI__builtin_rvv_vget_v_i16m4_i16m2:
3635   case RISCV::BI__builtin_rvv_vget_v_i32m4_i32m2:
3636   case RISCV::BI__builtin_rvv_vget_v_i64m4_i64m2:
3637   case RISCV::BI__builtin_rvv_vget_v_f32m4_f32m2:
3638   case RISCV::BI__builtin_rvv_vget_v_f64m4_f64m2:
3639   case RISCV::BI__builtin_rvv_vget_v_u8m4_u8m2:
3640   case RISCV::BI__builtin_rvv_vget_v_u16m4_u16m2:
3641   case RISCV::BI__builtin_rvv_vget_v_u32m4_u32m2:
3642   case RISCV::BI__builtin_rvv_vget_v_u64m4_u64m2:
3643   case RISCV::BI__builtin_rvv_vget_v_i8m8_i8m4:
3644   case RISCV::BI__builtin_rvv_vget_v_i16m8_i16m4:
3645   case RISCV::BI__builtin_rvv_vget_v_i32m8_i32m4:
3646   case RISCV::BI__builtin_rvv_vget_v_i64m8_i64m4:
3647   case RISCV::BI__builtin_rvv_vget_v_f32m8_f32m4:
3648   case RISCV::BI__builtin_rvv_vget_v_f64m8_f64m4:
3649   case RISCV::BI__builtin_rvv_vget_v_u8m8_u8m4:
3650   case RISCV::BI__builtin_rvv_vget_v_u16m8_u16m4:
3651   case RISCV::BI__builtin_rvv_vget_v_u32m8_u32m4:
3652   case RISCV::BI__builtin_rvv_vget_v_u64m8_u64m4:
3653     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1);
3654   case RISCV::BI__builtin_rvv_vget_v_i8m4_i8m1:
3655   case RISCV::BI__builtin_rvv_vget_v_i16m4_i16m1:
3656   case RISCV::BI__builtin_rvv_vget_v_i32m4_i32m1:
3657   case RISCV::BI__builtin_rvv_vget_v_i64m4_i64m1:
3658   case RISCV::BI__builtin_rvv_vget_v_f32m4_f32m1:
3659   case RISCV::BI__builtin_rvv_vget_v_f64m4_f64m1:
3660   case RISCV::BI__builtin_rvv_vget_v_u8m4_u8m1:
3661   case RISCV::BI__builtin_rvv_vget_v_u16m4_u16m1:
3662   case RISCV::BI__builtin_rvv_vget_v_u32m4_u32m1:
3663   case RISCV::BI__builtin_rvv_vget_v_u64m4_u64m1:
3664   case RISCV::BI__builtin_rvv_vget_v_i8m8_i8m2:
3665   case RISCV::BI__builtin_rvv_vget_v_i16m8_i16m2:
3666   case RISCV::BI__builtin_rvv_vget_v_i32m8_i32m2:
3667   case RISCV::BI__builtin_rvv_vget_v_i64m8_i64m2:
3668   case RISCV::BI__builtin_rvv_vget_v_f32m8_f32m2:
3669   case RISCV::BI__builtin_rvv_vget_v_f64m8_f64m2:
3670   case RISCV::BI__builtin_rvv_vget_v_u8m8_u8m2:
3671   case RISCV::BI__builtin_rvv_vget_v_u16m8_u16m2:
3672   case RISCV::BI__builtin_rvv_vget_v_u32m8_u32m2:
3673   case RISCV::BI__builtin_rvv_vget_v_u64m8_u64m2:
3674     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 3);
3675   case RISCV::BI__builtin_rvv_vget_v_i8m8_i8m1:
3676   case RISCV::BI__builtin_rvv_vget_v_i16m8_i16m1:
3677   case RISCV::BI__builtin_rvv_vget_v_i32m8_i32m1:
3678   case RISCV::BI__builtin_rvv_vget_v_i64m8_i64m1:
3679   case RISCV::BI__builtin_rvv_vget_v_f32m8_f32m1:
3680   case RISCV::BI__builtin_rvv_vget_v_f64m8_f64m1:
3681   case RISCV::BI__builtin_rvv_vget_v_u8m8_u8m1:
3682   case RISCV::BI__builtin_rvv_vget_v_u16m8_u16m1:
3683   case RISCV::BI__builtin_rvv_vget_v_u32m8_u32m1:
3684   case RISCV::BI__builtin_rvv_vget_v_u64m8_u64m1:
3685     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 7);
3686   case RISCV::BI__builtin_rvv_vset_v_i8m1_i8m2:
3687   case RISCV::BI__builtin_rvv_vset_v_i16m1_i16m2:
3688   case RISCV::BI__builtin_rvv_vset_v_i32m1_i32m2:
3689   case RISCV::BI__builtin_rvv_vset_v_i64m1_i64m2:
3690   case RISCV::BI__builtin_rvv_vset_v_f32m1_f32m2:
3691   case RISCV::BI__builtin_rvv_vset_v_f64m1_f64m2:
3692   case RISCV::BI__builtin_rvv_vset_v_u8m1_u8m2:
3693   case RISCV::BI__builtin_rvv_vset_v_u16m1_u16m2:
3694   case RISCV::BI__builtin_rvv_vset_v_u32m1_u32m2:
3695   case RISCV::BI__builtin_rvv_vset_v_u64m1_u64m2:
3696   case RISCV::BI__builtin_rvv_vset_v_i8m2_i8m4:
3697   case RISCV::BI__builtin_rvv_vset_v_i16m2_i16m4:
3698   case RISCV::BI__builtin_rvv_vset_v_i32m2_i32m4:
3699   case RISCV::BI__builtin_rvv_vset_v_i64m2_i64m4:
3700   case RISCV::BI__builtin_rvv_vset_v_f32m2_f32m4:
3701   case RISCV::BI__builtin_rvv_vset_v_f64m2_f64m4:
3702   case RISCV::BI__builtin_rvv_vset_v_u8m2_u8m4:
3703   case RISCV::BI__builtin_rvv_vset_v_u16m2_u16m4:
3704   case RISCV::BI__builtin_rvv_vset_v_u32m2_u32m4:
3705   case RISCV::BI__builtin_rvv_vset_v_u64m2_u64m4:
3706   case RISCV::BI__builtin_rvv_vset_v_i8m4_i8m8:
3707   case RISCV::BI__builtin_rvv_vset_v_i16m4_i16m8:
3708   case RISCV::BI__builtin_rvv_vset_v_i32m4_i32m8:
3709   case RISCV::BI__builtin_rvv_vset_v_i64m4_i64m8:
3710   case RISCV::BI__builtin_rvv_vset_v_f32m4_f32m8:
3711   case RISCV::BI__builtin_rvv_vset_v_f64m4_f64m8:
3712   case RISCV::BI__builtin_rvv_vset_v_u8m4_u8m8:
3713   case RISCV::BI__builtin_rvv_vset_v_u16m4_u16m8:
3714   case RISCV::BI__builtin_rvv_vset_v_u32m4_u32m8:
3715   case RISCV::BI__builtin_rvv_vset_v_u64m4_u64m8:
3716     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1);
3717   case RISCV::BI__builtin_rvv_vset_v_i8m1_i8m4:
3718   case RISCV::BI__builtin_rvv_vset_v_i16m1_i16m4:
3719   case RISCV::BI__builtin_rvv_vset_v_i32m1_i32m4:
3720   case RISCV::BI__builtin_rvv_vset_v_i64m1_i64m4:
3721   case RISCV::BI__builtin_rvv_vset_v_f32m1_f32m4:
3722   case RISCV::BI__builtin_rvv_vset_v_f64m1_f64m4:
3723   case RISCV::BI__builtin_rvv_vset_v_u8m1_u8m4:
3724   case RISCV::BI__builtin_rvv_vset_v_u16m1_u16m4:
3725   case RISCV::BI__builtin_rvv_vset_v_u32m1_u32m4:
3726   case RISCV::BI__builtin_rvv_vset_v_u64m1_u64m4:
3727   case RISCV::BI__builtin_rvv_vset_v_i8m2_i8m8:
3728   case RISCV::BI__builtin_rvv_vset_v_i16m2_i16m8:
3729   case RISCV::BI__builtin_rvv_vset_v_i32m2_i32m8:
3730   case RISCV::BI__builtin_rvv_vset_v_i64m2_i64m8:
3731   case RISCV::BI__builtin_rvv_vset_v_f32m2_f32m8:
3732   case RISCV::BI__builtin_rvv_vset_v_f64m2_f64m8:
3733   case RISCV::BI__builtin_rvv_vset_v_u8m2_u8m8:
3734   case RISCV::BI__builtin_rvv_vset_v_u16m2_u16m8:
3735   case RISCV::BI__builtin_rvv_vset_v_u32m2_u32m8:
3736   case RISCV::BI__builtin_rvv_vset_v_u64m2_u64m8:
3737     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 3);
3738   case RISCV::BI__builtin_rvv_vset_v_i8m1_i8m8:
3739   case RISCV::BI__builtin_rvv_vset_v_i16m1_i16m8:
3740   case RISCV::BI__builtin_rvv_vset_v_i32m1_i32m8:
3741   case RISCV::BI__builtin_rvv_vset_v_i64m1_i64m8:
3742   case RISCV::BI__builtin_rvv_vset_v_f32m1_f32m8:
3743   case RISCV::BI__builtin_rvv_vset_v_f64m1_f64m8:
3744   case RISCV::BI__builtin_rvv_vset_v_u8m1_u8m8:
3745   case RISCV::BI__builtin_rvv_vset_v_u16m1_u16m8:
3746   case RISCV::BI__builtin_rvv_vset_v_u32m1_u32m8:
3747   case RISCV::BI__builtin_rvv_vset_v_u64m1_u64m8:
3748     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 7);
3749   }
3750 
3751   return false;
3752 }
3753 
3754 bool Sema::CheckSystemZBuiltinFunctionCall(unsigned BuiltinID,
3755                                            CallExpr *TheCall) {
3756   if (BuiltinID == SystemZ::BI__builtin_tabort) {
3757     Expr *Arg = TheCall->getArg(0);
3758     if (Optional<llvm::APSInt> AbortCode = Arg->getIntegerConstantExpr(Context))
3759       if (AbortCode->getSExtValue() >= 0 && AbortCode->getSExtValue() < 256)
3760         return Diag(Arg->getBeginLoc(), diag::err_systemz_invalid_tabort_code)
3761                << Arg->getSourceRange();
3762   }
3763 
3764   // For intrinsics which take an immediate value as part of the instruction,
3765   // range check them here.
3766   unsigned i = 0, l = 0, u = 0;
3767   switch (BuiltinID) {
3768   default: return false;
3769   case SystemZ::BI__builtin_s390_lcbb: i = 1; l = 0; u = 15; break;
3770   case SystemZ::BI__builtin_s390_verimb:
3771   case SystemZ::BI__builtin_s390_verimh:
3772   case SystemZ::BI__builtin_s390_verimf:
3773   case SystemZ::BI__builtin_s390_verimg: i = 3; l = 0; u = 255; break;
3774   case SystemZ::BI__builtin_s390_vfaeb:
3775   case SystemZ::BI__builtin_s390_vfaeh:
3776   case SystemZ::BI__builtin_s390_vfaef:
3777   case SystemZ::BI__builtin_s390_vfaebs:
3778   case SystemZ::BI__builtin_s390_vfaehs:
3779   case SystemZ::BI__builtin_s390_vfaefs:
3780   case SystemZ::BI__builtin_s390_vfaezb:
3781   case SystemZ::BI__builtin_s390_vfaezh:
3782   case SystemZ::BI__builtin_s390_vfaezf:
3783   case SystemZ::BI__builtin_s390_vfaezbs:
3784   case SystemZ::BI__builtin_s390_vfaezhs:
3785   case SystemZ::BI__builtin_s390_vfaezfs: i = 2; l = 0; u = 15; break;
3786   case SystemZ::BI__builtin_s390_vfisb:
3787   case SystemZ::BI__builtin_s390_vfidb:
3788     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 15) ||
3789            SemaBuiltinConstantArgRange(TheCall, 2, 0, 15);
3790   case SystemZ::BI__builtin_s390_vftcisb:
3791   case SystemZ::BI__builtin_s390_vftcidb: i = 1; l = 0; u = 4095; break;
3792   case SystemZ::BI__builtin_s390_vlbb: i = 1; l = 0; u = 15; break;
3793   case SystemZ::BI__builtin_s390_vpdi: i = 2; l = 0; u = 15; break;
3794   case SystemZ::BI__builtin_s390_vsldb: i = 2; l = 0; u = 15; break;
3795   case SystemZ::BI__builtin_s390_vstrcb:
3796   case SystemZ::BI__builtin_s390_vstrch:
3797   case SystemZ::BI__builtin_s390_vstrcf:
3798   case SystemZ::BI__builtin_s390_vstrczb:
3799   case SystemZ::BI__builtin_s390_vstrczh:
3800   case SystemZ::BI__builtin_s390_vstrczf:
3801   case SystemZ::BI__builtin_s390_vstrcbs:
3802   case SystemZ::BI__builtin_s390_vstrchs:
3803   case SystemZ::BI__builtin_s390_vstrcfs:
3804   case SystemZ::BI__builtin_s390_vstrczbs:
3805   case SystemZ::BI__builtin_s390_vstrczhs:
3806   case SystemZ::BI__builtin_s390_vstrczfs: i = 3; l = 0; u = 15; break;
3807   case SystemZ::BI__builtin_s390_vmslg: i = 3; l = 0; u = 15; break;
3808   case SystemZ::BI__builtin_s390_vfminsb:
3809   case SystemZ::BI__builtin_s390_vfmaxsb:
3810   case SystemZ::BI__builtin_s390_vfmindb:
3811   case SystemZ::BI__builtin_s390_vfmaxdb: i = 2; l = 0; u = 15; break;
3812   case SystemZ::BI__builtin_s390_vsld: i = 2; l = 0; u = 7; break;
3813   case SystemZ::BI__builtin_s390_vsrd: i = 2; l = 0; u = 7; break;
3814   case SystemZ::BI__builtin_s390_vclfnhs:
3815   case SystemZ::BI__builtin_s390_vclfnls:
3816   case SystemZ::BI__builtin_s390_vcfn:
3817   case SystemZ::BI__builtin_s390_vcnf: i = 1; l = 0; u = 15; break;
3818   case SystemZ::BI__builtin_s390_vcrnfs: i = 2; l = 0; u = 15; break;
3819   }
3820   return SemaBuiltinConstantArgRange(TheCall, i, l, u);
3821 }
3822 
3823 /// SemaBuiltinCpuSupports - Handle __builtin_cpu_supports(char *).
3824 /// This checks that the target supports __builtin_cpu_supports and
3825 /// that the string argument is constant and valid.
3826 static bool SemaBuiltinCpuSupports(Sema &S, const TargetInfo &TI,
3827                                    CallExpr *TheCall) {
3828   Expr *Arg = TheCall->getArg(0);
3829 
3830   // Check if the argument is a string literal.
3831   if (!isa<StringLiteral>(Arg->IgnoreParenImpCasts()))
3832     return S.Diag(TheCall->getBeginLoc(), diag::err_expr_not_string_literal)
3833            << Arg->getSourceRange();
3834 
3835   // Check the contents of the string.
3836   StringRef Feature =
3837       cast<StringLiteral>(Arg->IgnoreParenImpCasts())->getString();
3838   if (!TI.validateCpuSupports(Feature))
3839     return S.Diag(TheCall->getBeginLoc(), diag::err_invalid_cpu_supports)
3840            << Arg->getSourceRange();
3841   return false;
3842 }
3843 
3844 /// SemaBuiltinCpuIs - Handle __builtin_cpu_is(char *).
3845 /// This checks that the target supports __builtin_cpu_is and
3846 /// that the string argument is constant and valid.
3847 static bool SemaBuiltinCpuIs(Sema &S, const TargetInfo &TI, CallExpr *TheCall) {
3848   Expr *Arg = TheCall->getArg(0);
3849 
3850   // Check if the argument is a string literal.
3851   if (!isa<StringLiteral>(Arg->IgnoreParenImpCasts()))
3852     return S.Diag(TheCall->getBeginLoc(), diag::err_expr_not_string_literal)
3853            << Arg->getSourceRange();
3854 
3855   // Check the contents of the string.
3856   StringRef Feature =
3857       cast<StringLiteral>(Arg->IgnoreParenImpCasts())->getString();
3858   if (!TI.validateCpuIs(Feature))
3859     return S.Diag(TheCall->getBeginLoc(), diag::err_invalid_cpu_is)
3860            << Arg->getSourceRange();
3861   return false;
3862 }
3863 
3864 // Check if the rounding mode is legal.
3865 bool Sema::CheckX86BuiltinRoundingOrSAE(unsigned BuiltinID, CallExpr *TheCall) {
3866   // Indicates if this instruction has rounding control or just SAE.
3867   bool HasRC = false;
3868 
3869   unsigned ArgNum = 0;
3870   switch (BuiltinID) {
3871   default:
3872     return false;
3873   case X86::BI__builtin_ia32_vcvttsd2si32:
3874   case X86::BI__builtin_ia32_vcvttsd2si64:
3875   case X86::BI__builtin_ia32_vcvttsd2usi32:
3876   case X86::BI__builtin_ia32_vcvttsd2usi64:
3877   case X86::BI__builtin_ia32_vcvttss2si32:
3878   case X86::BI__builtin_ia32_vcvttss2si64:
3879   case X86::BI__builtin_ia32_vcvttss2usi32:
3880   case X86::BI__builtin_ia32_vcvttss2usi64:
3881   case X86::BI__builtin_ia32_vcvttsh2si32:
3882   case X86::BI__builtin_ia32_vcvttsh2si64:
3883   case X86::BI__builtin_ia32_vcvttsh2usi32:
3884   case X86::BI__builtin_ia32_vcvttsh2usi64:
3885     ArgNum = 1;
3886     break;
3887   case X86::BI__builtin_ia32_maxpd512:
3888   case X86::BI__builtin_ia32_maxps512:
3889   case X86::BI__builtin_ia32_minpd512:
3890   case X86::BI__builtin_ia32_minps512:
3891   case X86::BI__builtin_ia32_maxph512:
3892   case X86::BI__builtin_ia32_minph512:
3893     ArgNum = 2;
3894     break;
3895   case X86::BI__builtin_ia32_vcvtph2pd512_mask:
3896   case X86::BI__builtin_ia32_vcvtph2psx512_mask:
3897   case X86::BI__builtin_ia32_cvtps2pd512_mask:
3898   case X86::BI__builtin_ia32_cvttpd2dq512_mask:
3899   case X86::BI__builtin_ia32_cvttpd2qq512_mask:
3900   case X86::BI__builtin_ia32_cvttpd2udq512_mask:
3901   case X86::BI__builtin_ia32_cvttpd2uqq512_mask:
3902   case X86::BI__builtin_ia32_cvttps2dq512_mask:
3903   case X86::BI__builtin_ia32_cvttps2qq512_mask:
3904   case X86::BI__builtin_ia32_cvttps2udq512_mask:
3905   case X86::BI__builtin_ia32_cvttps2uqq512_mask:
3906   case X86::BI__builtin_ia32_vcvttph2w512_mask:
3907   case X86::BI__builtin_ia32_vcvttph2uw512_mask:
3908   case X86::BI__builtin_ia32_vcvttph2dq512_mask:
3909   case X86::BI__builtin_ia32_vcvttph2udq512_mask:
3910   case X86::BI__builtin_ia32_vcvttph2qq512_mask:
3911   case X86::BI__builtin_ia32_vcvttph2uqq512_mask:
3912   case X86::BI__builtin_ia32_exp2pd_mask:
3913   case X86::BI__builtin_ia32_exp2ps_mask:
3914   case X86::BI__builtin_ia32_getexppd512_mask:
3915   case X86::BI__builtin_ia32_getexpps512_mask:
3916   case X86::BI__builtin_ia32_getexpph512_mask:
3917   case X86::BI__builtin_ia32_rcp28pd_mask:
3918   case X86::BI__builtin_ia32_rcp28ps_mask:
3919   case X86::BI__builtin_ia32_rsqrt28pd_mask:
3920   case X86::BI__builtin_ia32_rsqrt28ps_mask:
3921   case X86::BI__builtin_ia32_vcomisd:
3922   case X86::BI__builtin_ia32_vcomiss:
3923   case X86::BI__builtin_ia32_vcomish:
3924   case X86::BI__builtin_ia32_vcvtph2ps512_mask:
3925     ArgNum = 3;
3926     break;
3927   case X86::BI__builtin_ia32_cmppd512_mask:
3928   case X86::BI__builtin_ia32_cmpps512_mask:
3929   case X86::BI__builtin_ia32_cmpsd_mask:
3930   case X86::BI__builtin_ia32_cmpss_mask:
3931   case X86::BI__builtin_ia32_cmpsh_mask:
3932   case X86::BI__builtin_ia32_vcvtsh2sd_round_mask:
3933   case X86::BI__builtin_ia32_vcvtsh2ss_round_mask:
3934   case X86::BI__builtin_ia32_cvtss2sd_round_mask:
3935   case X86::BI__builtin_ia32_getexpsd128_round_mask:
3936   case X86::BI__builtin_ia32_getexpss128_round_mask:
3937   case X86::BI__builtin_ia32_getexpsh128_round_mask:
3938   case X86::BI__builtin_ia32_getmantpd512_mask:
3939   case X86::BI__builtin_ia32_getmantps512_mask:
3940   case X86::BI__builtin_ia32_getmantph512_mask:
3941   case X86::BI__builtin_ia32_maxsd_round_mask:
3942   case X86::BI__builtin_ia32_maxss_round_mask:
3943   case X86::BI__builtin_ia32_maxsh_round_mask:
3944   case X86::BI__builtin_ia32_minsd_round_mask:
3945   case X86::BI__builtin_ia32_minss_round_mask:
3946   case X86::BI__builtin_ia32_minsh_round_mask:
3947   case X86::BI__builtin_ia32_rcp28sd_round_mask:
3948   case X86::BI__builtin_ia32_rcp28ss_round_mask:
3949   case X86::BI__builtin_ia32_reducepd512_mask:
3950   case X86::BI__builtin_ia32_reduceps512_mask:
3951   case X86::BI__builtin_ia32_reduceph512_mask:
3952   case X86::BI__builtin_ia32_rndscalepd_mask:
3953   case X86::BI__builtin_ia32_rndscaleps_mask:
3954   case X86::BI__builtin_ia32_rndscaleph_mask:
3955   case X86::BI__builtin_ia32_rsqrt28sd_round_mask:
3956   case X86::BI__builtin_ia32_rsqrt28ss_round_mask:
3957     ArgNum = 4;
3958     break;
3959   case X86::BI__builtin_ia32_fixupimmpd512_mask:
3960   case X86::BI__builtin_ia32_fixupimmpd512_maskz:
3961   case X86::BI__builtin_ia32_fixupimmps512_mask:
3962   case X86::BI__builtin_ia32_fixupimmps512_maskz:
3963   case X86::BI__builtin_ia32_fixupimmsd_mask:
3964   case X86::BI__builtin_ia32_fixupimmsd_maskz:
3965   case X86::BI__builtin_ia32_fixupimmss_mask:
3966   case X86::BI__builtin_ia32_fixupimmss_maskz:
3967   case X86::BI__builtin_ia32_getmantsd_round_mask:
3968   case X86::BI__builtin_ia32_getmantss_round_mask:
3969   case X86::BI__builtin_ia32_getmantsh_round_mask:
3970   case X86::BI__builtin_ia32_rangepd512_mask:
3971   case X86::BI__builtin_ia32_rangeps512_mask:
3972   case X86::BI__builtin_ia32_rangesd128_round_mask:
3973   case X86::BI__builtin_ia32_rangess128_round_mask:
3974   case X86::BI__builtin_ia32_reducesd_mask:
3975   case X86::BI__builtin_ia32_reducess_mask:
3976   case X86::BI__builtin_ia32_reducesh_mask:
3977   case X86::BI__builtin_ia32_rndscalesd_round_mask:
3978   case X86::BI__builtin_ia32_rndscaless_round_mask:
3979   case X86::BI__builtin_ia32_rndscalesh_round_mask:
3980     ArgNum = 5;
3981     break;
3982   case X86::BI__builtin_ia32_vcvtsd2si64:
3983   case X86::BI__builtin_ia32_vcvtsd2si32:
3984   case X86::BI__builtin_ia32_vcvtsd2usi32:
3985   case X86::BI__builtin_ia32_vcvtsd2usi64:
3986   case X86::BI__builtin_ia32_vcvtss2si32:
3987   case X86::BI__builtin_ia32_vcvtss2si64:
3988   case X86::BI__builtin_ia32_vcvtss2usi32:
3989   case X86::BI__builtin_ia32_vcvtss2usi64:
3990   case X86::BI__builtin_ia32_vcvtsh2si32:
3991   case X86::BI__builtin_ia32_vcvtsh2si64:
3992   case X86::BI__builtin_ia32_vcvtsh2usi32:
3993   case X86::BI__builtin_ia32_vcvtsh2usi64:
3994   case X86::BI__builtin_ia32_sqrtpd512:
3995   case X86::BI__builtin_ia32_sqrtps512:
3996   case X86::BI__builtin_ia32_sqrtph512:
3997     ArgNum = 1;
3998     HasRC = true;
3999     break;
4000   case X86::BI__builtin_ia32_addph512:
4001   case X86::BI__builtin_ia32_divph512:
4002   case X86::BI__builtin_ia32_mulph512:
4003   case X86::BI__builtin_ia32_subph512:
4004   case X86::BI__builtin_ia32_addpd512:
4005   case X86::BI__builtin_ia32_addps512:
4006   case X86::BI__builtin_ia32_divpd512:
4007   case X86::BI__builtin_ia32_divps512:
4008   case X86::BI__builtin_ia32_mulpd512:
4009   case X86::BI__builtin_ia32_mulps512:
4010   case X86::BI__builtin_ia32_subpd512:
4011   case X86::BI__builtin_ia32_subps512:
4012   case X86::BI__builtin_ia32_cvtsi2sd64:
4013   case X86::BI__builtin_ia32_cvtsi2ss32:
4014   case X86::BI__builtin_ia32_cvtsi2ss64:
4015   case X86::BI__builtin_ia32_cvtusi2sd64:
4016   case X86::BI__builtin_ia32_cvtusi2ss32:
4017   case X86::BI__builtin_ia32_cvtusi2ss64:
4018   case X86::BI__builtin_ia32_vcvtusi2sh:
4019   case X86::BI__builtin_ia32_vcvtusi642sh:
4020   case X86::BI__builtin_ia32_vcvtsi2sh:
4021   case X86::BI__builtin_ia32_vcvtsi642sh:
4022     ArgNum = 2;
4023     HasRC = true;
4024     break;
4025   case X86::BI__builtin_ia32_cvtdq2ps512_mask:
4026   case X86::BI__builtin_ia32_cvtudq2ps512_mask:
4027   case X86::BI__builtin_ia32_vcvtpd2ph512_mask:
4028   case X86::BI__builtin_ia32_vcvtps2phx512_mask:
4029   case X86::BI__builtin_ia32_cvtpd2ps512_mask:
4030   case X86::BI__builtin_ia32_cvtpd2dq512_mask:
4031   case X86::BI__builtin_ia32_cvtpd2qq512_mask:
4032   case X86::BI__builtin_ia32_cvtpd2udq512_mask:
4033   case X86::BI__builtin_ia32_cvtpd2uqq512_mask:
4034   case X86::BI__builtin_ia32_cvtps2dq512_mask:
4035   case X86::BI__builtin_ia32_cvtps2qq512_mask:
4036   case X86::BI__builtin_ia32_cvtps2udq512_mask:
4037   case X86::BI__builtin_ia32_cvtps2uqq512_mask:
4038   case X86::BI__builtin_ia32_cvtqq2pd512_mask:
4039   case X86::BI__builtin_ia32_cvtqq2ps512_mask:
4040   case X86::BI__builtin_ia32_cvtuqq2pd512_mask:
4041   case X86::BI__builtin_ia32_cvtuqq2ps512_mask:
4042   case X86::BI__builtin_ia32_vcvtdq2ph512_mask:
4043   case X86::BI__builtin_ia32_vcvtudq2ph512_mask:
4044   case X86::BI__builtin_ia32_vcvtw2ph512_mask:
4045   case X86::BI__builtin_ia32_vcvtuw2ph512_mask:
4046   case X86::BI__builtin_ia32_vcvtph2w512_mask:
4047   case X86::BI__builtin_ia32_vcvtph2uw512_mask:
4048   case X86::BI__builtin_ia32_vcvtph2dq512_mask:
4049   case X86::BI__builtin_ia32_vcvtph2udq512_mask:
4050   case X86::BI__builtin_ia32_vcvtph2qq512_mask:
4051   case X86::BI__builtin_ia32_vcvtph2uqq512_mask:
4052   case X86::BI__builtin_ia32_vcvtqq2ph512_mask:
4053   case X86::BI__builtin_ia32_vcvtuqq2ph512_mask:
4054     ArgNum = 3;
4055     HasRC = true;
4056     break;
4057   case X86::BI__builtin_ia32_addsh_round_mask:
4058   case X86::BI__builtin_ia32_addss_round_mask:
4059   case X86::BI__builtin_ia32_addsd_round_mask:
4060   case X86::BI__builtin_ia32_divsh_round_mask:
4061   case X86::BI__builtin_ia32_divss_round_mask:
4062   case X86::BI__builtin_ia32_divsd_round_mask:
4063   case X86::BI__builtin_ia32_mulsh_round_mask:
4064   case X86::BI__builtin_ia32_mulss_round_mask:
4065   case X86::BI__builtin_ia32_mulsd_round_mask:
4066   case X86::BI__builtin_ia32_subsh_round_mask:
4067   case X86::BI__builtin_ia32_subss_round_mask:
4068   case X86::BI__builtin_ia32_subsd_round_mask:
4069   case X86::BI__builtin_ia32_scalefph512_mask:
4070   case X86::BI__builtin_ia32_scalefpd512_mask:
4071   case X86::BI__builtin_ia32_scalefps512_mask:
4072   case X86::BI__builtin_ia32_scalefsd_round_mask:
4073   case X86::BI__builtin_ia32_scalefss_round_mask:
4074   case X86::BI__builtin_ia32_scalefsh_round_mask:
4075   case X86::BI__builtin_ia32_cvtsd2ss_round_mask:
4076   case X86::BI__builtin_ia32_vcvtss2sh_round_mask:
4077   case X86::BI__builtin_ia32_vcvtsd2sh_round_mask:
4078   case X86::BI__builtin_ia32_sqrtsd_round_mask:
4079   case X86::BI__builtin_ia32_sqrtss_round_mask:
4080   case X86::BI__builtin_ia32_sqrtsh_round_mask:
4081   case X86::BI__builtin_ia32_vfmaddsd3_mask:
4082   case X86::BI__builtin_ia32_vfmaddsd3_maskz:
4083   case X86::BI__builtin_ia32_vfmaddsd3_mask3:
4084   case X86::BI__builtin_ia32_vfmaddss3_mask:
4085   case X86::BI__builtin_ia32_vfmaddss3_maskz:
4086   case X86::BI__builtin_ia32_vfmaddss3_mask3:
4087   case X86::BI__builtin_ia32_vfmaddsh3_mask:
4088   case X86::BI__builtin_ia32_vfmaddsh3_maskz:
4089   case X86::BI__builtin_ia32_vfmaddsh3_mask3:
4090   case X86::BI__builtin_ia32_vfmaddpd512_mask:
4091   case X86::BI__builtin_ia32_vfmaddpd512_maskz:
4092   case X86::BI__builtin_ia32_vfmaddpd512_mask3:
4093   case X86::BI__builtin_ia32_vfmsubpd512_mask3:
4094   case X86::BI__builtin_ia32_vfmaddps512_mask:
4095   case X86::BI__builtin_ia32_vfmaddps512_maskz:
4096   case X86::BI__builtin_ia32_vfmaddps512_mask3:
4097   case X86::BI__builtin_ia32_vfmsubps512_mask3:
4098   case X86::BI__builtin_ia32_vfmaddph512_mask:
4099   case X86::BI__builtin_ia32_vfmaddph512_maskz:
4100   case X86::BI__builtin_ia32_vfmaddph512_mask3:
4101   case X86::BI__builtin_ia32_vfmsubph512_mask3:
4102   case X86::BI__builtin_ia32_vfmaddsubpd512_mask:
4103   case X86::BI__builtin_ia32_vfmaddsubpd512_maskz:
4104   case X86::BI__builtin_ia32_vfmaddsubpd512_mask3:
4105   case X86::BI__builtin_ia32_vfmsubaddpd512_mask3:
4106   case X86::BI__builtin_ia32_vfmaddsubps512_mask:
4107   case X86::BI__builtin_ia32_vfmaddsubps512_maskz:
4108   case X86::BI__builtin_ia32_vfmaddsubps512_mask3:
4109   case X86::BI__builtin_ia32_vfmsubaddps512_mask3:
4110   case X86::BI__builtin_ia32_vfmaddsubph512_mask:
4111   case X86::BI__builtin_ia32_vfmaddsubph512_maskz:
4112   case X86::BI__builtin_ia32_vfmaddsubph512_mask3:
4113   case X86::BI__builtin_ia32_vfmsubaddph512_mask3:
4114   case X86::BI__builtin_ia32_vfmaddcsh_mask:
4115   case X86::BI__builtin_ia32_vfmaddcph512_mask:
4116   case X86::BI__builtin_ia32_vfmaddcph512_maskz:
4117   case X86::BI__builtin_ia32_vfcmaddcsh_mask:
4118   case X86::BI__builtin_ia32_vfcmaddcph512_mask:
4119   case X86::BI__builtin_ia32_vfcmaddcph512_maskz:
4120   case X86::BI__builtin_ia32_vfmulcsh_mask:
4121   case X86::BI__builtin_ia32_vfmulcph512_mask:
4122   case X86::BI__builtin_ia32_vfcmulcsh_mask:
4123   case X86::BI__builtin_ia32_vfcmulcph512_mask:
4124     ArgNum = 4;
4125     HasRC = true;
4126     break;
4127   }
4128 
4129   llvm::APSInt Result;
4130 
4131   // We can't check the value of a dependent argument.
4132   Expr *Arg = TheCall->getArg(ArgNum);
4133   if (Arg->isTypeDependent() || Arg->isValueDependent())
4134     return false;
4135 
4136   // Check constant-ness first.
4137   if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
4138     return true;
4139 
4140   // Make sure rounding mode is either ROUND_CUR_DIRECTION or ROUND_NO_EXC bit
4141   // is set. If the intrinsic has rounding control(bits 1:0), make sure its only
4142   // combined with ROUND_NO_EXC. If the intrinsic does not have rounding
4143   // control, allow ROUND_NO_EXC and ROUND_CUR_DIRECTION together.
4144   if (Result == 4/*ROUND_CUR_DIRECTION*/ ||
4145       Result == 8/*ROUND_NO_EXC*/ ||
4146       (!HasRC && Result == 12/*ROUND_CUR_DIRECTION|ROUND_NO_EXC*/) ||
4147       (HasRC && Result.getZExtValue() >= 8 && Result.getZExtValue() <= 11))
4148     return false;
4149 
4150   return Diag(TheCall->getBeginLoc(), diag::err_x86_builtin_invalid_rounding)
4151          << Arg->getSourceRange();
4152 }
4153 
4154 // Check if the gather/scatter scale is legal.
4155 bool Sema::CheckX86BuiltinGatherScatterScale(unsigned BuiltinID,
4156                                              CallExpr *TheCall) {
4157   unsigned ArgNum = 0;
4158   switch (BuiltinID) {
4159   default:
4160     return false;
4161   case X86::BI__builtin_ia32_gatherpfdpd:
4162   case X86::BI__builtin_ia32_gatherpfdps:
4163   case X86::BI__builtin_ia32_gatherpfqpd:
4164   case X86::BI__builtin_ia32_gatherpfqps:
4165   case X86::BI__builtin_ia32_scatterpfdpd:
4166   case X86::BI__builtin_ia32_scatterpfdps:
4167   case X86::BI__builtin_ia32_scatterpfqpd:
4168   case X86::BI__builtin_ia32_scatterpfqps:
4169     ArgNum = 3;
4170     break;
4171   case X86::BI__builtin_ia32_gatherd_pd:
4172   case X86::BI__builtin_ia32_gatherd_pd256:
4173   case X86::BI__builtin_ia32_gatherq_pd:
4174   case X86::BI__builtin_ia32_gatherq_pd256:
4175   case X86::BI__builtin_ia32_gatherd_ps:
4176   case X86::BI__builtin_ia32_gatherd_ps256:
4177   case X86::BI__builtin_ia32_gatherq_ps:
4178   case X86::BI__builtin_ia32_gatherq_ps256:
4179   case X86::BI__builtin_ia32_gatherd_q:
4180   case X86::BI__builtin_ia32_gatherd_q256:
4181   case X86::BI__builtin_ia32_gatherq_q:
4182   case X86::BI__builtin_ia32_gatherq_q256:
4183   case X86::BI__builtin_ia32_gatherd_d:
4184   case X86::BI__builtin_ia32_gatherd_d256:
4185   case X86::BI__builtin_ia32_gatherq_d:
4186   case X86::BI__builtin_ia32_gatherq_d256:
4187   case X86::BI__builtin_ia32_gather3div2df:
4188   case X86::BI__builtin_ia32_gather3div2di:
4189   case X86::BI__builtin_ia32_gather3div4df:
4190   case X86::BI__builtin_ia32_gather3div4di:
4191   case X86::BI__builtin_ia32_gather3div4sf:
4192   case X86::BI__builtin_ia32_gather3div4si:
4193   case X86::BI__builtin_ia32_gather3div8sf:
4194   case X86::BI__builtin_ia32_gather3div8si:
4195   case X86::BI__builtin_ia32_gather3siv2df:
4196   case X86::BI__builtin_ia32_gather3siv2di:
4197   case X86::BI__builtin_ia32_gather3siv4df:
4198   case X86::BI__builtin_ia32_gather3siv4di:
4199   case X86::BI__builtin_ia32_gather3siv4sf:
4200   case X86::BI__builtin_ia32_gather3siv4si:
4201   case X86::BI__builtin_ia32_gather3siv8sf:
4202   case X86::BI__builtin_ia32_gather3siv8si:
4203   case X86::BI__builtin_ia32_gathersiv8df:
4204   case X86::BI__builtin_ia32_gathersiv16sf:
4205   case X86::BI__builtin_ia32_gatherdiv8df:
4206   case X86::BI__builtin_ia32_gatherdiv16sf:
4207   case X86::BI__builtin_ia32_gathersiv8di:
4208   case X86::BI__builtin_ia32_gathersiv16si:
4209   case X86::BI__builtin_ia32_gatherdiv8di:
4210   case X86::BI__builtin_ia32_gatherdiv16si:
4211   case X86::BI__builtin_ia32_scatterdiv2df:
4212   case X86::BI__builtin_ia32_scatterdiv2di:
4213   case X86::BI__builtin_ia32_scatterdiv4df:
4214   case X86::BI__builtin_ia32_scatterdiv4di:
4215   case X86::BI__builtin_ia32_scatterdiv4sf:
4216   case X86::BI__builtin_ia32_scatterdiv4si:
4217   case X86::BI__builtin_ia32_scatterdiv8sf:
4218   case X86::BI__builtin_ia32_scatterdiv8si:
4219   case X86::BI__builtin_ia32_scattersiv2df:
4220   case X86::BI__builtin_ia32_scattersiv2di:
4221   case X86::BI__builtin_ia32_scattersiv4df:
4222   case X86::BI__builtin_ia32_scattersiv4di:
4223   case X86::BI__builtin_ia32_scattersiv4sf:
4224   case X86::BI__builtin_ia32_scattersiv4si:
4225   case X86::BI__builtin_ia32_scattersiv8sf:
4226   case X86::BI__builtin_ia32_scattersiv8si:
4227   case X86::BI__builtin_ia32_scattersiv8df:
4228   case X86::BI__builtin_ia32_scattersiv16sf:
4229   case X86::BI__builtin_ia32_scatterdiv8df:
4230   case X86::BI__builtin_ia32_scatterdiv16sf:
4231   case X86::BI__builtin_ia32_scattersiv8di:
4232   case X86::BI__builtin_ia32_scattersiv16si:
4233   case X86::BI__builtin_ia32_scatterdiv8di:
4234   case X86::BI__builtin_ia32_scatterdiv16si:
4235     ArgNum = 4;
4236     break;
4237   }
4238 
4239   llvm::APSInt Result;
4240 
4241   // We can't check the value of a dependent argument.
4242   Expr *Arg = TheCall->getArg(ArgNum);
4243   if (Arg->isTypeDependent() || Arg->isValueDependent())
4244     return false;
4245 
4246   // Check constant-ness first.
4247   if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
4248     return true;
4249 
4250   if (Result == 1 || Result == 2 || Result == 4 || Result == 8)
4251     return false;
4252 
4253   return Diag(TheCall->getBeginLoc(), diag::err_x86_builtin_invalid_scale)
4254          << Arg->getSourceRange();
4255 }
4256 
4257 enum { TileRegLow = 0, TileRegHigh = 7 };
4258 
4259 bool Sema::CheckX86BuiltinTileArgumentsRange(CallExpr *TheCall,
4260                                              ArrayRef<int> ArgNums) {
4261   for (int ArgNum : ArgNums) {
4262     if (SemaBuiltinConstantArgRange(TheCall, ArgNum, TileRegLow, TileRegHigh))
4263       return true;
4264   }
4265   return false;
4266 }
4267 
4268 bool Sema::CheckX86BuiltinTileDuplicate(CallExpr *TheCall,
4269                                         ArrayRef<int> ArgNums) {
4270   // Because the max number of tile register is TileRegHigh + 1, so here we use
4271   // each bit to represent the usage of them in bitset.
4272   std::bitset<TileRegHigh + 1> ArgValues;
4273   for (int ArgNum : ArgNums) {
4274     Expr *Arg = TheCall->getArg(ArgNum);
4275     if (Arg->isTypeDependent() || Arg->isValueDependent())
4276       continue;
4277 
4278     llvm::APSInt Result;
4279     if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
4280       return true;
4281     int ArgExtValue = Result.getExtValue();
4282     assert((ArgExtValue >= TileRegLow || ArgExtValue <= TileRegHigh) &&
4283            "Incorrect tile register num.");
4284     if (ArgValues.test(ArgExtValue))
4285       return Diag(TheCall->getBeginLoc(),
4286                   diag::err_x86_builtin_tile_arg_duplicate)
4287              << TheCall->getArg(ArgNum)->getSourceRange();
4288     ArgValues.set(ArgExtValue);
4289   }
4290   return false;
4291 }
4292 
4293 bool Sema::CheckX86BuiltinTileRangeAndDuplicate(CallExpr *TheCall,
4294                                                 ArrayRef<int> ArgNums) {
4295   return CheckX86BuiltinTileArgumentsRange(TheCall, ArgNums) ||
4296          CheckX86BuiltinTileDuplicate(TheCall, ArgNums);
4297 }
4298 
4299 bool Sema::CheckX86BuiltinTileArguments(unsigned BuiltinID, CallExpr *TheCall) {
4300   switch (BuiltinID) {
4301   default:
4302     return false;
4303   case X86::BI__builtin_ia32_tileloadd64:
4304   case X86::BI__builtin_ia32_tileloaddt164:
4305   case X86::BI__builtin_ia32_tilestored64:
4306   case X86::BI__builtin_ia32_tilezero:
4307     return CheckX86BuiltinTileArgumentsRange(TheCall, 0);
4308   case X86::BI__builtin_ia32_tdpbssd:
4309   case X86::BI__builtin_ia32_tdpbsud:
4310   case X86::BI__builtin_ia32_tdpbusd:
4311   case X86::BI__builtin_ia32_tdpbuud:
4312   case X86::BI__builtin_ia32_tdpbf16ps:
4313     return CheckX86BuiltinTileRangeAndDuplicate(TheCall, {0, 1, 2});
4314   }
4315 }
4316 static bool isX86_32Builtin(unsigned BuiltinID) {
4317   // These builtins only work on x86-32 targets.
4318   switch (BuiltinID) {
4319   case X86::BI__builtin_ia32_readeflags_u32:
4320   case X86::BI__builtin_ia32_writeeflags_u32:
4321     return true;
4322   }
4323 
4324   return false;
4325 }
4326 
4327 bool Sema::CheckX86BuiltinFunctionCall(const TargetInfo &TI, unsigned BuiltinID,
4328                                        CallExpr *TheCall) {
4329   if (BuiltinID == X86::BI__builtin_cpu_supports)
4330     return SemaBuiltinCpuSupports(*this, TI, TheCall);
4331 
4332   if (BuiltinID == X86::BI__builtin_cpu_is)
4333     return SemaBuiltinCpuIs(*this, TI, TheCall);
4334 
4335   // Check for 32-bit only builtins on a 64-bit target.
4336   const llvm::Triple &TT = TI.getTriple();
4337   if (TT.getArch() != llvm::Triple::x86 && isX86_32Builtin(BuiltinID))
4338     return Diag(TheCall->getCallee()->getBeginLoc(),
4339                 diag::err_32_bit_builtin_64_bit_tgt);
4340 
4341   // If the intrinsic has rounding or SAE make sure its valid.
4342   if (CheckX86BuiltinRoundingOrSAE(BuiltinID, TheCall))
4343     return true;
4344 
4345   // If the intrinsic has a gather/scatter scale immediate make sure its valid.
4346   if (CheckX86BuiltinGatherScatterScale(BuiltinID, TheCall))
4347     return true;
4348 
4349   // If the intrinsic has a tile arguments, make sure they are valid.
4350   if (CheckX86BuiltinTileArguments(BuiltinID, TheCall))
4351     return true;
4352 
4353   // For intrinsics which take an immediate value as part of the instruction,
4354   // range check them here.
4355   int i = 0, l = 0, u = 0;
4356   switch (BuiltinID) {
4357   default:
4358     return false;
4359   case X86::BI__builtin_ia32_vec_ext_v2si:
4360   case X86::BI__builtin_ia32_vec_ext_v2di:
4361   case X86::BI__builtin_ia32_vextractf128_pd256:
4362   case X86::BI__builtin_ia32_vextractf128_ps256:
4363   case X86::BI__builtin_ia32_vextractf128_si256:
4364   case X86::BI__builtin_ia32_extract128i256:
4365   case X86::BI__builtin_ia32_extractf64x4_mask:
4366   case X86::BI__builtin_ia32_extracti64x4_mask:
4367   case X86::BI__builtin_ia32_extractf32x8_mask:
4368   case X86::BI__builtin_ia32_extracti32x8_mask:
4369   case X86::BI__builtin_ia32_extractf64x2_256_mask:
4370   case X86::BI__builtin_ia32_extracti64x2_256_mask:
4371   case X86::BI__builtin_ia32_extractf32x4_256_mask:
4372   case X86::BI__builtin_ia32_extracti32x4_256_mask:
4373     i = 1; l = 0; u = 1;
4374     break;
4375   case X86::BI__builtin_ia32_vec_set_v2di:
4376   case X86::BI__builtin_ia32_vinsertf128_pd256:
4377   case X86::BI__builtin_ia32_vinsertf128_ps256:
4378   case X86::BI__builtin_ia32_vinsertf128_si256:
4379   case X86::BI__builtin_ia32_insert128i256:
4380   case X86::BI__builtin_ia32_insertf32x8:
4381   case X86::BI__builtin_ia32_inserti32x8:
4382   case X86::BI__builtin_ia32_insertf64x4:
4383   case X86::BI__builtin_ia32_inserti64x4:
4384   case X86::BI__builtin_ia32_insertf64x2_256:
4385   case X86::BI__builtin_ia32_inserti64x2_256:
4386   case X86::BI__builtin_ia32_insertf32x4_256:
4387   case X86::BI__builtin_ia32_inserti32x4_256:
4388     i = 2; l = 0; u = 1;
4389     break;
4390   case X86::BI__builtin_ia32_vpermilpd:
4391   case X86::BI__builtin_ia32_vec_ext_v4hi:
4392   case X86::BI__builtin_ia32_vec_ext_v4si:
4393   case X86::BI__builtin_ia32_vec_ext_v4sf:
4394   case X86::BI__builtin_ia32_vec_ext_v4di:
4395   case X86::BI__builtin_ia32_extractf32x4_mask:
4396   case X86::BI__builtin_ia32_extracti32x4_mask:
4397   case X86::BI__builtin_ia32_extractf64x2_512_mask:
4398   case X86::BI__builtin_ia32_extracti64x2_512_mask:
4399     i = 1; l = 0; u = 3;
4400     break;
4401   case X86::BI_mm_prefetch:
4402   case X86::BI__builtin_ia32_vec_ext_v8hi:
4403   case X86::BI__builtin_ia32_vec_ext_v8si:
4404     i = 1; l = 0; u = 7;
4405     break;
4406   case X86::BI__builtin_ia32_sha1rnds4:
4407   case X86::BI__builtin_ia32_blendpd:
4408   case X86::BI__builtin_ia32_shufpd:
4409   case X86::BI__builtin_ia32_vec_set_v4hi:
4410   case X86::BI__builtin_ia32_vec_set_v4si:
4411   case X86::BI__builtin_ia32_vec_set_v4di:
4412   case X86::BI__builtin_ia32_shuf_f32x4_256:
4413   case X86::BI__builtin_ia32_shuf_f64x2_256:
4414   case X86::BI__builtin_ia32_shuf_i32x4_256:
4415   case X86::BI__builtin_ia32_shuf_i64x2_256:
4416   case X86::BI__builtin_ia32_insertf64x2_512:
4417   case X86::BI__builtin_ia32_inserti64x2_512:
4418   case X86::BI__builtin_ia32_insertf32x4:
4419   case X86::BI__builtin_ia32_inserti32x4:
4420     i = 2; l = 0; u = 3;
4421     break;
4422   case X86::BI__builtin_ia32_vpermil2pd:
4423   case X86::BI__builtin_ia32_vpermil2pd256:
4424   case X86::BI__builtin_ia32_vpermil2ps:
4425   case X86::BI__builtin_ia32_vpermil2ps256:
4426     i = 3; l = 0; u = 3;
4427     break;
4428   case X86::BI__builtin_ia32_cmpb128_mask:
4429   case X86::BI__builtin_ia32_cmpw128_mask:
4430   case X86::BI__builtin_ia32_cmpd128_mask:
4431   case X86::BI__builtin_ia32_cmpq128_mask:
4432   case X86::BI__builtin_ia32_cmpb256_mask:
4433   case X86::BI__builtin_ia32_cmpw256_mask:
4434   case X86::BI__builtin_ia32_cmpd256_mask:
4435   case X86::BI__builtin_ia32_cmpq256_mask:
4436   case X86::BI__builtin_ia32_cmpb512_mask:
4437   case X86::BI__builtin_ia32_cmpw512_mask:
4438   case X86::BI__builtin_ia32_cmpd512_mask:
4439   case X86::BI__builtin_ia32_cmpq512_mask:
4440   case X86::BI__builtin_ia32_ucmpb128_mask:
4441   case X86::BI__builtin_ia32_ucmpw128_mask:
4442   case X86::BI__builtin_ia32_ucmpd128_mask:
4443   case X86::BI__builtin_ia32_ucmpq128_mask:
4444   case X86::BI__builtin_ia32_ucmpb256_mask:
4445   case X86::BI__builtin_ia32_ucmpw256_mask:
4446   case X86::BI__builtin_ia32_ucmpd256_mask:
4447   case X86::BI__builtin_ia32_ucmpq256_mask:
4448   case X86::BI__builtin_ia32_ucmpb512_mask:
4449   case X86::BI__builtin_ia32_ucmpw512_mask:
4450   case X86::BI__builtin_ia32_ucmpd512_mask:
4451   case X86::BI__builtin_ia32_ucmpq512_mask:
4452   case X86::BI__builtin_ia32_vpcomub:
4453   case X86::BI__builtin_ia32_vpcomuw:
4454   case X86::BI__builtin_ia32_vpcomud:
4455   case X86::BI__builtin_ia32_vpcomuq:
4456   case X86::BI__builtin_ia32_vpcomb:
4457   case X86::BI__builtin_ia32_vpcomw:
4458   case X86::BI__builtin_ia32_vpcomd:
4459   case X86::BI__builtin_ia32_vpcomq:
4460   case X86::BI__builtin_ia32_vec_set_v8hi:
4461   case X86::BI__builtin_ia32_vec_set_v8si:
4462     i = 2; l = 0; u = 7;
4463     break;
4464   case X86::BI__builtin_ia32_vpermilpd256:
4465   case X86::BI__builtin_ia32_roundps:
4466   case X86::BI__builtin_ia32_roundpd:
4467   case X86::BI__builtin_ia32_roundps256:
4468   case X86::BI__builtin_ia32_roundpd256:
4469   case X86::BI__builtin_ia32_getmantpd128_mask:
4470   case X86::BI__builtin_ia32_getmantpd256_mask:
4471   case X86::BI__builtin_ia32_getmantps128_mask:
4472   case X86::BI__builtin_ia32_getmantps256_mask:
4473   case X86::BI__builtin_ia32_getmantpd512_mask:
4474   case X86::BI__builtin_ia32_getmantps512_mask:
4475   case X86::BI__builtin_ia32_getmantph128_mask:
4476   case X86::BI__builtin_ia32_getmantph256_mask:
4477   case X86::BI__builtin_ia32_getmantph512_mask:
4478   case X86::BI__builtin_ia32_vec_ext_v16qi:
4479   case X86::BI__builtin_ia32_vec_ext_v16hi:
4480     i = 1; l = 0; u = 15;
4481     break;
4482   case X86::BI__builtin_ia32_pblendd128:
4483   case X86::BI__builtin_ia32_blendps:
4484   case X86::BI__builtin_ia32_blendpd256:
4485   case X86::BI__builtin_ia32_shufpd256:
4486   case X86::BI__builtin_ia32_roundss:
4487   case X86::BI__builtin_ia32_roundsd:
4488   case X86::BI__builtin_ia32_rangepd128_mask:
4489   case X86::BI__builtin_ia32_rangepd256_mask:
4490   case X86::BI__builtin_ia32_rangepd512_mask:
4491   case X86::BI__builtin_ia32_rangeps128_mask:
4492   case X86::BI__builtin_ia32_rangeps256_mask:
4493   case X86::BI__builtin_ia32_rangeps512_mask:
4494   case X86::BI__builtin_ia32_getmantsd_round_mask:
4495   case X86::BI__builtin_ia32_getmantss_round_mask:
4496   case X86::BI__builtin_ia32_getmantsh_round_mask:
4497   case X86::BI__builtin_ia32_vec_set_v16qi:
4498   case X86::BI__builtin_ia32_vec_set_v16hi:
4499     i = 2; l = 0; u = 15;
4500     break;
4501   case X86::BI__builtin_ia32_vec_ext_v32qi:
4502     i = 1; l = 0; u = 31;
4503     break;
4504   case X86::BI__builtin_ia32_cmpps:
4505   case X86::BI__builtin_ia32_cmpss:
4506   case X86::BI__builtin_ia32_cmppd:
4507   case X86::BI__builtin_ia32_cmpsd:
4508   case X86::BI__builtin_ia32_cmpps256:
4509   case X86::BI__builtin_ia32_cmppd256:
4510   case X86::BI__builtin_ia32_cmpps128_mask:
4511   case X86::BI__builtin_ia32_cmppd128_mask:
4512   case X86::BI__builtin_ia32_cmpps256_mask:
4513   case X86::BI__builtin_ia32_cmppd256_mask:
4514   case X86::BI__builtin_ia32_cmpps512_mask:
4515   case X86::BI__builtin_ia32_cmppd512_mask:
4516   case X86::BI__builtin_ia32_cmpsd_mask:
4517   case X86::BI__builtin_ia32_cmpss_mask:
4518   case X86::BI__builtin_ia32_vec_set_v32qi:
4519     i = 2; l = 0; u = 31;
4520     break;
4521   case X86::BI__builtin_ia32_permdf256:
4522   case X86::BI__builtin_ia32_permdi256:
4523   case X86::BI__builtin_ia32_permdf512:
4524   case X86::BI__builtin_ia32_permdi512:
4525   case X86::BI__builtin_ia32_vpermilps:
4526   case X86::BI__builtin_ia32_vpermilps256:
4527   case X86::BI__builtin_ia32_vpermilpd512:
4528   case X86::BI__builtin_ia32_vpermilps512:
4529   case X86::BI__builtin_ia32_pshufd:
4530   case X86::BI__builtin_ia32_pshufd256:
4531   case X86::BI__builtin_ia32_pshufd512:
4532   case X86::BI__builtin_ia32_pshufhw:
4533   case X86::BI__builtin_ia32_pshufhw256:
4534   case X86::BI__builtin_ia32_pshufhw512:
4535   case X86::BI__builtin_ia32_pshuflw:
4536   case X86::BI__builtin_ia32_pshuflw256:
4537   case X86::BI__builtin_ia32_pshuflw512:
4538   case X86::BI__builtin_ia32_vcvtps2ph:
4539   case X86::BI__builtin_ia32_vcvtps2ph_mask:
4540   case X86::BI__builtin_ia32_vcvtps2ph256:
4541   case X86::BI__builtin_ia32_vcvtps2ph256_mask:
4542   case X86::BI__builtin_ia32_vcvtps2ph512_mask:
4543   case X86::BI__builtin_ia32_rndscaleps_128_mask:
4544   case X86::BI__builtin_ia32_rndscalepd_128_mask:
4545   case X86::BI__builtin_ia32_rndscaleps_256_mask:
4546   case X86::BI__builtin_ia32_rndscalepd_256_mask:
4547   case X86::BI__builtin_ia32_rndscaleps_mask:
4548   case X86::BI__builtin_ia32_rndscalepd_mask:
4549   case X86::BI__builtin_ia32_rndscaleph_mask:
4550   case X86::BI__builtin_ia32_reducepd128_mask:
4551   case X86::BI__builtin_ia32_reducepd256_mask:
4552   case X86::BI__builtin_ia32_reducepd512_mask:
4553   case X86::BI__builtin_ia32_reduceps128_mask:
4554   case X86::BI__builtin_ia32_reduceps256_mask:
4555   case X86::BI__builtin_ia32_reduceps512_mask:
4556   case X86::BI__builtin_ia32_reduceph128_mask:
4557   case X86::BI__builtin_ia32_reduceph256_mask:
4558   case X86::BI__builtin_ia32_reduceph512_mask:
4559   case X86::BI__builtin_ia32_prold512:
4560   case X86::BI__builtin_ia32_prolq512:
4561   case X86::BI__builtin_ia32_prold128:
4562   case X86::BI__builtin_ia32_prold256:
4563   case X86::BI__builtin_ia32_prolq128:
4564   case X86::BI__builtin_ia32_prolq256:
4565   case X86::BI__builtin_ia32_prord512:
4566   case X86::BI__builtin_ia32_prorq512:
4567   case X86::BI__builtin_ia32_prord128:
4568   case X86::BI__builtin_ia32_prord256:
4569   case X86::BI__builtin_ia32_prorq128:
4570   case X86::BI__builtin_ia32_prorq256:
4571   case X86::BI__builtin_ia32_fpclasspd128_mask:
4572   case X86::BI__builtin_ia32_fpclasspd256_mask:
4573   case X86::BI__builtin_ia32_fpclassps128_mask:
4574   case X86::BI__builtin_ia32_fpclassps256_mask:
4575   case X86::BI__builtin_ia32_fpclassps512_mask:
4576   case X86::BI__builtin_ia32_fpclasspd512_mask:
4577   case X86::BI__builtin_ia32_fpclassph128_mask:
4578   case X86::BI__builtin_ia32_fpclassph256_mask:
4579   case X86::BI__builtin_ia32_fpclassph512_mask:
4580   case X86::BI__builtin_ia32_fpclasssd_mask:
4581   case X86::BI__builtin_ia32_fpclassss_mask:
4582   case X86::BI__builtin_ia32_fpclasssh_mask:
4583   case X86::BI__builtin_ia32_pslldqi128_byteshift:
4584   case X86::BI__builtin_ia32_pslldqi256_byteshift:
4585   case X86::BI__builtin_ia32_pslldqi512_byteshift:
4586   case X86::BI__builtin_ia32_psrldqi128_byteshift:
4587   case X86::BI__builtin_ia32_psrldqi256_byteshift:
4588   case X86::BI__builtin_ia32_psrldqi512_byteshift:
4589   case X86::BI__builtin_ia32_kshiftliqi:
4590   case X86::BI__builtin_ia32_kshiftlihi:
4591   case X86::BI__builtin_ia32_kshiftlisi:
4592   case X86::BI__builtin_ia32_kshiftlidi:
4593   case X86::BI__builtin_ia32_kshiftriqi:
4594   case X86::BI__builtin_ia32_kshiftrihi:
4595   case X86::BI__builtin_ia32_kshiftrisi:
4596   case X86::BI__builtin_ia32_kshiftridi:
4597     i = 1; l = 0; u = 255;
4598     break;
4599   case X86::BI__builtin_ia32_vperm2f128_pd256:
4600   case X86::BI__builtin_ia32_vperm2f128_ps256:
4601   case X86::BI__builtin_ia32_vperm2f128_si256:
4602   case X86::BI__builtin_ia32_permti256:
4603   case X86::BI__builtin_ia32_pblendw128:
4604   case X86::BI__builtin_ia32_pblendw256:
4605   case X86::BI__builtin_ia32_blendps256:
4606   case X86::BI__builtin_ia32_pblendd256:
4607   case X86::BI__builtin_ia32_palignr128:
4608   case X86::BI__builtin_ia32_palignr256:
4609   case X86::BI__builtin_ia32_palignr512:
4610   case X86::BI__builtin_ia32_alignq512:
4611   case X86::BI__builtin_ia32_alignd512:
4612   case X86::BI__builtin_ia32_alignd128:
4613   case X86::BI__builtin_ia32_alignd256:
4614   case X86::BI__builtin_ia32_alignq128:
4615   case X86::BI__builtin_ia32_alignq256:
4616   case X86::BI__builtin_ia32_vcomisd:
4617   case X86::BI__builtin_ia32_vcomiss:
4618   case X86::BI__builtin_ia32_shuf_f32x4:
4619   case X86::BI__builtin_ia32_shuf_f64x2:
4620   case X86::BI__builtin_ia32_shuf_i32x4:
4621   case X86::BI__builtin_ia32_shuf_i64x2:
4622   case X86::BI__builtin_ia32_shufpd512:
4623   case X86::BI__builtin_ia32_shufps:
4624   case X86::BI__builtin_ia32_shufps256:
4625   case X86::BI__builtin_ia32_shufps512:
4626   case X86::BI__builtin_ia32_dbpsadbw128:
4627   case X86::BI__builtin_ia32_dbpsadbw256:
4628   case X86::BI__builtin_ia32_dbpsadbw512:
4629   case X86::BI__builtin_ia32_vpshldd128:
4630   case X86::BI__builtin_ia32_vpshldd256:
4631   case X86::BI__builtin_ia32_vpshldd512:
4632   case X86::BI__builtin_ia32_vpshldq128:
4633   case X86::BI__builtin_ia32_vpshldq256:
4634   case X86::BI__builtin_ia32_vpshldq512:
4635   case X86::BI__builtin_ia32_vpshldw128:
4636   case X86::BI__builtin_ia32_vpshldw256:
4637   case X86::BI__builtin_ia32_vpshldw512:
4638   case X86::BI__builtin_ia32_vpshrdd128:
4639   case X86::BI__builtin_ia32_vpshrdd256:
4640   case X86::BI__builtin_ia32_vpshrdd512:
4641   case X86::BI__builtin_ia32_vpshrdq128:
4642   case X86::BI__builtin_ia32_vpshrdq256:
4643   case X86::BI__builtin_ia32_vpshrdq512:
4644   case X86::BI__builtin_ia32_vpshrdw128:
4645   case X86::BI__builtin_ia32_vpshrdw256:
4646   case X86::BI__builtin_ia32_vpshrdw512:
4647     i = 2; l = 0; u = 255;
4648     break;
4649   case X86::BI__builtin_ia32_fixupimmpd512_mask:
4650   case X86::BI__builtin_ia32_fixupimmpd512_maskz:
4651   case X86::BI__builtin_ia32_fixupimmps512_mask:
4652   case X86::BI__builtin_ia32_fixupimmps512_maskz:
4653   case X86::BI__builtin_ia32_fixupimmsd_mask:
4654   case X86::BI__builtin_ia32_fixupimmsd_maskz:
4655   case X86::BI__builtin_ia32_fixupimmss_mask:
4656   case X86::BI__builtin_ia32_fixupimmss_maskz:
4657   case X86::BI__builtin_ia32_fixupimmpd128_mask:
4658   case X86::BI__builtin_ia32_fixupimmpd128_maskz:
4659   case X86::BI__builtin_ia32_fixupimmpd256_mask:
4660   case X86::BI__builtin_ia32_fixupimmpd256_maskz:
4661   case X86::BI__builtin_ia32_fixupimmps128_mask:
4662   case X86::BI__builtin_ia32_fixupimmps128_maskz:
4663   case X86::BI__builtin_ia32_fixupimmps256_mask:
4664   case X86::BI__builtin_ia32_fixupimmps256_maskz:
4665   case X86::BI__builtin_ia32_pternlogd512_mask:
4666   case X86::BI__builtin_ia32_pternlogd512_maskz:
4667   case X86::BI__builtin_ia32_pternlogq512_mask:
4668   case X86::BI__builtin_ia32_pternlogq512_maskz:
4669   case X86::BI__builtin_ia32_pternlogd128_mask:
4670   case X86::BI__builtin_ia32_pternlogd128_maskz:
4671   case X86::BI__builtin_ia32_pternlogd256_mask:
4672   case X86::BI__builtin_ia32_pternlogd256_maskz:
4673   case X86::BI__builtin_ia32_pternlogq128_mask:
4674   case X86::BI__builtin_ia32_pternlogq128_maskz:
4675   case X86::BI__builtin_ia32_pternlogq256_mask:
4676   case X86::BI__builtin_ia32_pternlogq256_maskz:
4677     i = 3; l = 0; u = 255;
4678     break;
4679   case X86::BI__builtin_ia32_gatherpfdpd:
4680   case X86::BI__builtin_ia32_gatherpfdps:
4681   case X86::BI__builtin_ia32_gatherpfqpd:
4682   case X86::BI__builtin_ia32_gatherpfqps:
4683   case X86::BI__builtin_ia32_scatterpfdpd:
4684   case X86::BI__builtin_ia32_scatterpfdps:
4685   case X86::BI__builtin_ia32_scatterpfqpd:
4686   case X86::BI__builtin_ia32_scatterpfqps:
4687     i = 4; l = 2; u = 3;
4688     break;
4689   case X86::BI__builtin_ia32_reducesd_mask:
4690   case X86::BI__builtin_ia32_reducess_mask:
4691   case X86::BI__builtin_ia32_rndscalesd_round_mask:
4692   case X86::BI__builtin_ia32_rndscaless_round_mask:
4693   case X86::BI__builtin_ia32_rndscalesh_round_mask:
4694   case X86::BI__builtin_ia32_reducesh_mask:
4695     i = 4; l = 0; u = 255;
4696     break;
4697   }
4698 
4699   // Note that we don't force a hard error on the range check here, allowing
4700   // template-generated or macro-generated dead code to potentially have out-of-
4701   // range values. These need to code generate, but don't need to necessarily
4702   // make any sense. We use a warning that defaults to an error.
4703   return SemaBuiltinConstantArgRange(TheCall, i, l, u, /*RangeIsError*/ false);
4704 }
4705 
4706 /// Given a FunctionDecl's FormatAttr, attempts to populate the FomatStringInfo
4707 /// parameter with the FormatAttr's correct format_idx and firstDataArg.
4708 /// Returns true when the format fits the function and the FormatStringInfo has
4709 /// been populated.
4710 bool Sema::getFormatStringInfo(const FormatAttr *Format, bool IsCXXMember,
4711                                FormatStringInfo *FSI) {
4712   FSI->HasVAListArg = Format->getFirstArg() == 0;
4713   FSI->FormatIdx = Format->getFormatIdx() - 1;
4714   FSI->FirstDataArg = FSI->HasVAListArg ? 0 : Format->getFirstArg() - 1;
4715 
4716   // The way the format attribute works in GCC, the implicit this argument
4717   // of member functions is counted. However, it doesn't appear in our own
4718   // lists, so decrement format_idx in that case.
4719   if (IsCXXMember) {
4720     if(FSI->FormatIdx == 0)
4721       return false;
4722     --FSI->FormatIdx;
4723     if (FSI->FirstDataArg != 0)
4724       --FSI->FirstDataArg;
4725   }
4726   return true;
4727 }
4728 
4729 /// Checks if a the given expression evaluates to null.
4730 ///
4731 /// Returns true if the value evaluates to null.
4732 static bool CheckNonNullExpr(Sema &S, const Expr *Expr) {
4733   // If the expression has non-null type, it doesn't evaluate to null.
4734   if (auto nullability
4735         = Expr->IgnoreImplicit()->getType()->getNullability(S.Context)) {
4736     if (*nullability == NullabilityKind::NonNull)
4737       return false;
4738   }
4739 
4740   // As a special case, transparent unions initialized with zero are
4741   // considered null for the purposes of the nonnull attribute.
4742   if (const RecordType *UT = Expr->getType()->getAsUnionType()) {
4743     if (UT->getDecl()->hasAttr<TransparentUnionAttr>())
4744       if (const CompoundLiteralExpr *CLE =
4745           dyn_cast<CompoundLiteralExpr>(Expr))
4746         if (const InitListExpr *ILE =
4747             dyn_cast<InitListExpr>(CLE->getInitializer()))
4748           Expr = ILE->getInit(0);
4749   }
4750 
4751   bool Result;
4752   return (!Expr->isValueDependent() &&
4753           Expr->EvaluateAsBooleanCondition(Result, S.Context) &&
4754           !Result);
4755 }
4756 
4757 static void CheckNonNullArgument(Sema &S,
4758                                  const Expr *ArgExpr,
4759                                  SourceLocation CallSiteLoc) {
4760   if (CheckNonNullExpr(S, ArgExpr))
4761     S.DiagRuntimeBehavior(CallSiteLoc, ArgExpr,
4762                           S.PDiag(diag::warn_null_arg)
4763                               << ArgExpr->getSourceRange());
4764 }
4765 
4766 bool Sema::GetFormatNSStringIdx(const FormatAttr *Format, unsigned &Idx) {
4767   FormatStringInfo FSI;
4768   if ((GetFormatStringType(Format) == FST_NSString) &&
4769       getFormatStringInfo(Format, false, &FSI)) {
4770     Idx = FSI.FormatIdx;
4771     return true;
4772   }
4773   return false;
4774 }
4775 
4776 /// Diagnose use of %s directive in an NSString which is being passed
4777 /// as formatting string to formatting method.
4778 static void
4779 DiagnoseCStringFormatDirectiveInCFAPI(Sema &S,
4780                                         const NamedDecl *FDecl,
4781                                         Expr **Args,
4782                                         unsigned NumArgs) {
4783   unsigned Idx = 0;
4784   bool Format = false;
4785   ObjCStringFormatFamily SFFamily = FDecl->getObjCFStringFormattingFamily();
4786   if (SFFamily == ObjCStringFormatFamily::SFF_CFString) {
4787     Idx = 2;
4788     Format = true;
4789   }
4790   else
4791     for (const auto *I : FDecl->specific_attrs<FormatAttr>()) {
4792       if (S.GetFormatNSStringIdx(I, Idx)) {
4793         Format = true;
4794         break;
4795       }
4796     }
4797   if (!Format || NumArgs <= Idx)
4798     return;
4799   const Expr *FormatExpr = Args[Idx];
4800   if (const CStyleCastExpr *CSCE = dyn_cast<CStyleCastExpr>(FormatExpr))
4801     FormatExpr = CSCE->getSubExpr();
4802   const StringLiteral *FormatString;
4803   if (const ObjCStringLiteral *OSL =
4804       dyn_cast<ObjCStringLiteral>(FormatExpr->IgnoreParenImpCasts()))
4805     FormatString = OSL->getString();
4806   else
4807     FormatString = dyn_cast<StringLiteral>(FormatExpr->IgnoreParenImpCasts());
4808   if (!FormatString)
4809     return;
4810   if (S.FormatStringHasSArg(FormatString)) {
4811     S.Diag(FormatExpr->getExprLoc(), diag::warn_objc_cdirective_format_string)
4812       << "%s" << 1 << 1;
4813     S.Diag(FDecl->getLocation(), diag::note_entity_declared_at)
4814       << FDecl->getDeclName();
4815   }
4816 }
4817 
4818 /// Determine whether the given type has a non-null nullability annotation.
4819 static bool isNonNullType(ASTContext &ctx, QualType type) {
4820   if (auto nullability = type->getNullability(ctx))
4821     return *nullability == NullabilityKind::NonNull;
4822 
4823   return false;
4824 }
4825 
4826 static void CheckNonNullArguments(Sema &S,
4827                                   const NamedDecl *FDecl,
4828                                   const FunctionProtoType *Proto,
4829                                   ArrayRef<const Expr *> Args,
4830                                   SourceLocation CallSiteLoc) {
4831   assert((FDecl || Proto) && "Need a function declaration or prototype");
4832 
4833   // Already checked by by constant evaluator.
4834   if (S.isConstantEvaluated())
4835     return;
4836   // Check the attributes attached to the method/function itself.
4837   llvm::SmallBitVector NonNullArgs;
4838   if (FDecl) {
4839     // Handle the nonnull attribute on the function/method declaration itself.
4840     for (const auto *NonNull : FDecl->specific_attrs<NonNullAttr>()) {
4841       if (!NonNull->args_size()) {
4842         // Easy case: all pointer arguments are nonnull.
4843         for (const auto *Arg : Args)
4844           if (S.isValidPointerAttrType(Arg->getType()))
4845             CheckNonNullArgument(S, Arg, CallSiteLoc);
4846         return;
4847       }
4848 
4849       for (const ParamIdx &Idx : NonNull->args()) {
4850         unsigned IdxAST = Idx.getASTIndex();
4851         if (IdxAST >= Args.size())
4852           continue;
4853         if (NonNullArgs.empty())
4854           NonNullArgs.resize(Args.size());
4855         NonNullArgs.set(IdxAST);
4856       }
4857     }
4858   }
4859 
4860   if (FDecl && (isa<FunctionDecl>(FDecl) || isa<ObjCMethodDecl>(FDecl))) {
4861     // Handle the nonnull attribute on the parameters of the
4862     // function/method.
4863     ArrayRef<ParmVarDecl*> parms;
4864     if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(FDecl))
4865       parms = FD->parameters();
4866     else
4867       parms = cast<ObjCMethodDecl>(FDecl)->parameters();
4868 
4869     unsigned ParamIndex = 0;
4870     for (ArrayRef<ParmVarDecl*>::iterator I = parms.begin(), E = parms.end();
4871          I != E; ++I, ++ParamIndex) {
4872       const ParmVarDecl *PVD = *I;
4873       if (PVD->hasAttr<NonNullAttr>() ||
4874           isNonNullType(S.Context, PVD->getType())) {
4875         if (NonNullArgs.empty())
4876           NonNullArgs.resize(Args.size());
4877 
4878         NonNullArgs.set(ParamIndex);
4879       }
4880     }
4881   } else {
4882     // If we have a non-function, non-method declaration but no
4883     // function prototype, try to dig out the function prototype.
4884     if (!Proto) {
4885       if (const ValueDecl *VD = dyn_cast<ValueDecl>(FDecl)) {
4886         QualType type = VD->getType().getNonReferenceType();
4887         if (auto pointerType = type->getAs<PointerType>())
4888           type = pointerType->getPointeeType();
4889         else if (auto blockType = type->getAs<BlockPointerType>())
4890           type = blockType->getPointeeType();
4891         // FIXME: data member pointers?
4892 
4893         // Dig out the function prototype, if there is one.
4894         Proto = type->getAs<FunctionProtoType>();
4895       }
4896     }
4897 
4898     // Fill in non-null argument information from the nullability
4899     // information on the parameter types (if we have them).
4900     if (Proto) {
4901       unsigned Index = 0;
4902       for (auto paramType : Proto->getParamTypes()) {
4903         if (isNonNullType(S.Context, paramType)) {
4904           if (NonNullArgs.empty())
4905             NonNullArgs.resize(Args.size());
4906 
4907           NonNullArgs.set(Index);
4908         }
4909 
4910         ++Index;
4911       }
4912     }
4913   }
4914 
4915   // Check for non-null arguments.
4916   for (unsigned ArgIndex = 0, ArgIndexEnd = NonNullArgs.size();
4917        ArgIndex != ArgIndexEnd; ++ArgIndex) {
4918     if (NonNullArgs[ArgIndex])
4919       CheckNonNullArgument(S, Args[ArgIndex], CallSiteLoc);
4920   }
4921 }
4922 
4923 /// Warn if a pointer or reference argument passed to a function points to an
4924 /// object that is less aligned than the parameter. This can happen when
4925 /// creating a typedef with a lower alignment than the original type and then
4926 /// calling functions defined in terms of the original type.
4927 void Sema::CheckArgAlignment(SourceLocation Loc, NamedDecl *FDecl,
4928                              StringRef ParamName, QualType ArgTy,
4929                              QualType ParamTy) {
4930 
4931   // If a function accepts a pointer or reference type
4932   if (!ParamTy->isPointerType() && !ParamTy->isReferenceType())
4933     return;
4934 
4935   // If the parameter is a pointer type, get the pointee type for the
4936   // argument too. If the parameter is a reference type, don't try to get
4937   // the pointee type for the argument.
4938   if (ParamTy->isPointerType())
4939     ArgTy = ArgTy->getPointeeType();
4940 
4941   // Remove reference or pointer
4942   ParamTy = ParamTy->getPointeeType();
4943 
4944   // Find expected alignment, and the actual alignment of the passed object.
4945   // getTypeAlignInChars requires complete types
4946   if (ArgTy.isNull() || ParamTy->isIncompleteType() ||
4947       ArgTy->isIncompleteType() || ParamTy->isUndeducedType() ||
4948       ArgTy->isUndeducedType())
4949     return;
4950 
4951   CharUnits ParamAlign = Context.getTypeAlignInChars(ParamTy);
4952   CharUnits ArgAlign = Context.getTypeAlignInChars(ArgTy);
4953 
4954   // If the argument is less aligned than the parameter, there is a
4955   // potential alignment issue.
4956   if (ArgAlign < ParamAlign)
4957     Diag(Loc, diag::warn_param_mismatched_alignment)
4958         << (int)ArgAlign.getQuantity() << (int)ParamAlign.getQuantity()
4959         << ParamName << FDecl;
4960 }
4961 
4962 /// Handles the checks for format strings, non-POD arguments to vararg
4963 /// functions, NULL arguments passed to non-NULL parameters, and diagnose_if
4964 /// attributes.
4965 void Sema::checkCall(NamedDecl *FDecl, const FunctionProtoType *Proto,
4966                      const Expr *ThisArg, ArrayRef<const Expr *> Args,
4967                      bool IsMemberFunction, SourceLocation Loc,
4968                      SourceRange Range, VariadicCallType CallType) {
4969   // FIXME: We should check as much as we can in the template definition.
4970   if (CurContext->isDependentContext())
4971     return;
4972 
4973   // Printf and scanf checking.
4974   llvm::SmallBitVector CheckedVarArgs;
4975   if (FDecl) {
4976     for (const auto *I : FDecl->specific_attrs<FormatAttr>()) {
4977       // Only create vector if there are format attributes.
4978       CheckedVarArgs.resize(Args.size());
4979 
4980       CheckFormatArguments(I, Args, IsMemberFunction, CallType, Loc, Range,
4981                            CheckedVarArgs);
4982     }
4983   }
4984 
4985   // Refuse POD arguments that weren't caught by the format string
4986   // checks above.
4987   auto *FD = dyn_cast_or_null<FunctionDecl>(FDecl);
4988   if (CallType != VariadicDoesNotApply &&
4989       (!FD || FD->getBuiltinID() != Builtin::BI__noop)) {
4990     unsigned NumParams = Proto ? Proto->getNumParams()
4991                        : FDecl && isa<FunctionDecl>(FDecl)
4992                            ? cast<FunctionDecl>(FDecl)->getNumParams()
4993                        : FDecl && isa<ObjCMethodDecl>(FDecl)
4994                            ? cast<ObjCMethodDecl>(FDecl)->param_size()
4995                        : 0;
4996 
4997     for (unsigned ArgIdx = NumParams; ArgIdx < Args.size(); ++ArgIdx) {
4998       // Args[ArgIdx] can be null in malformed code.
4999       if (const Expr *Arg = Args[ArgIdx]) {
5000         if (CheckedVarArgs.empty() || !CheckedVarArgs[ArgIdx])
5001           checkVariadicArgument(Arg, CallType);
5002       }
5003     }
5004   }
5005 
5006   if (FDecl || Proto) {
5007     CheckNonNullArguments(*this, FDecl, Proto, Args, Loc);
5008 
5009     // Type safety checking.
5010     if (FDecl) {
5011       for (const auto *I : FDecl->specific_attrs<ArgumentWithTypeTagAttr>())
5012         CheckArgumentWithTypeTag(I, Args, Loc);
5013     }
5014   }
5015 
5016   // Check that passed arguments match the alignment of original arguments.
5017   // Try to get the missing prototype from the declaration.
5018   if (!Proto && FDecl) {
5019     const auto *FT = FDecl->getFunctionType();
5020     if (isa_and_nonnull<FunctionProtoType>(FT))
5021       Proto = cast<FunctionProtoType>(FDecl->getFunctionType());
5022   }
5023   if (Proto) {
5024     // For variadic functions, we may have more args than parameters.
5025     // For some K&R functions, we may have less args than parameters.
5026     const auto N = std::min<unsigned>(Proto->getNumParams(), Args.size());
5027     for (unsigned ArgIdx = 0; ArgIdx < N; ++ArgIdx) {
5028       // Args[ArgIdx] can be null in malformed code.
5029       if (const Expr *Arg = Args[ArgIdx]) {
5030         if (Arg->containsErrors())
5031           continue;
5032 
5033         QualType ParamTy = Proto->getParamType(ArgIdx);
5034         QualType ArgTy = Arg->getType();
5035         CheckArgAlignment(Arg->getExprLoc(), FDecl, std::to_string(ArgIdx + 1),
5036                           ArgTy, ParamTy);
5037       }
5038     }
5039   }
5040 
5041   if (FDecl && FDecl->hasAttr<AllocAlignAttr>()) {
5042     auto *AA = FDecl->getAttr<AllocAlignAttr>();
5043     const Expr *Arg = Args[AA->getParamIndex().getASTIndex()];
5044     if (!Arg->isValueDependent()) {
5045       Expr::EvalResult Align;
5046       if (Arg->EvaluateAsInt(Align, Context)) {
5047         const llvm::APSInt &I = Align.Val.getInt();
5048         if (!I.isPowerOf2())
5049           Diag(Arg->getExprLoc(), diag::warn_alignment_not_power_of_two)
5050               << Arg->getSourceRange();
5051 
5052         if (I > Sema::MaximumAlignment)
5053           Diag(Arg->getExprLoc(), diag::warn_assume_aligned_too_great)
5054               << Arg->getSourceRange() << Sema::MaximumAlignment;
5055       }
5056     }
5057   }
5058 
5059   if (FD)
5060     diagnoseArgDependentDiagnoseIfAttrs(FD, ThisArg, Args, Loc);
5061 }
5062 
5063 /// CheckConstructorCall - Check a constructor call for correctness and safety
5064 /// properties not enforced by the C type system.
5065 void Sema::CheckConstructorCall(FunctionDecl *FDecl, QualType ThisType,
5066                                 ArrayRef<const Expr *> Args,
5067                                 const FunctionProtoType *Proto,
5068                                 SourceLocation Loc) {
5069   VariadicCallType CallType =
5070       Proto->isVariadic() ? VariadicConstructor : VariadicDoesNotApply;
5071 
5072   auto *Ctor = cast<CXXConstructorDecl>(FDecl);
5073   CheckArgAlignment(Loc, FDecl, "'this'", Context.getPointerType(ThisType),
5074                     Context.getPointerType(Ctor->getThisObjectType()));
5075 
5076   checkCall(FDecl, Proto, /*ThisArg=*/nullptr, Args, /*IsMemberFunction=*/true,
5077             Loc, SourceRange(), CallType);
5078 }
5079 
5080 /// CheckFunctionCall - Check a direct function call for various correctness
5081 /// and safety properties not strictly enforced by the C type system.
5082 bool Sema::CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall,
5083                              const FunctionProtoType *Proto) {
5084   bool IsMemberOperatorCall = isa<CXXOperatorCallExpr>(TheCall) &&
5085                               isa<CXXMethodDecl>(FDecl);
5086   bool IsMemberFunction = isa<CXXMemberCallExpr>(TheCall) ||
5087                           IsMemberOperatorCall;
5088   VariadicCallType CallType = getVariadicCallType(FDecl, Proto,
5089                                                   TheCall->getCallee());
5090   Expr** Args = TheCall->getArgs();
5091   unsigned NumArgs = TheCall->getNumArgs();
5092 
5093   Expr *ImplicitThis = nullptr;
5094   if (IsMemberOperatorCall) {
5095     // If this is a call to a member operator, hide the first argument
5096     // from checkCall.
5097     // FIXME: Our choice of AST representation here is less than ideal.
5098     ImplicitThis = Args[0];
5099     ++Args;
5100     --NumArgs;
5101   } else if (IsMemberFunction)
5102     ImplicitThis =
5103         cast<CXXMemberCallExpr>(TheCall)->getImplicitObjectArgument();
5104 
5105   if (ImplicitThis) {
5106     // ImplicitThis may or may not be a pointer, depending on whether . or -> is
5107     // used.
5108     QualType ThisType = ImplicitThis->getType();
5109     if (!ThisType->isPointerType()) {
5110       assert(!ThisType->isReferenceType());
5111       ThisType = Context.getPointerType(ThisType);
5112     }
5113 
5114     QualType ThisTypeFromDecl =
5115         Context.getPointerType(cast<CXXMethodDecl>(FDecl)->getThisObjectType());
5116 
5117     CheckArgAlignment(TheCall->getRParenLoc(), FDecl, "'this'", ThisType,
5118                       ThisTypeFromDecl);
5119   }
5120 
5121   checkCall(FDecl, Proto, ImplicitThis, llvm::makeArrayRef(Args, NumArgs),
5122             IsMemberFunction, TheCall->getRParenLoc(),
5123             TheCall->getCallee()->getSourceRange(), CallType);
5124 
5125   IdentifierInfo *FnInfo = FDecl->getIdentifier();
5126   // None of the checks below are needed for functions that don't have
5127   // simple names (e.g., C++ conversion functions).
5128   if (!FnInfo)
5129     return false;
5130 
5131   CheckTCBEnforcement(TheCall, FDecl);
5132 
5133   CheckAbsoluteValueFunction(TheCall, FDecl);
5134   CheckMaxUnsignedZero(TheCall, FDecl);
5135 
5136   if (getLangOpts().ObjC)
5137     DiagnoseCStringFormatDirectiveInCFAPI(*this, FDecl, Args, NumArgs);
5138 
5139   unsigned CMId = FDecl->getMemoryFunctionKind();
5140 
5141   // Handle memory setting and copying functions.
5142   switch (CMId) {
5143   case 0:
5144     return false;
5145   case Builtin::BIstrlcpy: // fallthrough
5146   case Builtin::BIstrlcat:
5147     CheckStrlcpycatArguments(TheCall, FnInfo);
5148     break;
5149   case Builtin::BIstrncat:
5150     CheckStrncatArguments(TheCall, FnInfo);
5151     break;
5152   case Builtin::BIfree:
5153     CheckFreeArguments(TheCall);
5154     break;
5155   default:
5156     CheckMemaccessArguments(TheCall, CMId, FnInfo);
5157   }
5158 
5159   return false;
5160 }
5161 
5162 bool Sema::CheckObjCMethodCall(ObjCMethodDecl *Method, SourceLocation lbrac,
5163                                ArrayRef<const Expr *> Args) {
5164   VariadicCallType CallType =
5165       Method->isVariadic() ? VariadicMethod : VariadicDoesNotApply;
5166 
5167   checkCall(Method, nullptr, /*ThisArg=*/nullptr, Args,
5168             /*IsMemberFunction=*/false, lbrac, Method->getSourceRange(),
5169             CallType);
5170 
5171   return false;
5172 }
5173 
5174 bool Sema::CheckPointerCall(NamedDecl *NDecl, CallExpr *TheCall,
5175                             const FunctionProtoType *Proto) {
5176   QualType Ty;
5177   if (const auto *V = dyn_cast<VarDecl>(NDecl))
5178     Ty = V->getType().getNonReferenceType();
5179   else if (const auto *F = dyn_cast<FieldDecl>(NDecl))
5180     Ty = F->getType().getNonReferenceType();
5181   else
5182     return false;
5183 
5184   if (!Ty->isBlockPointerType() && !Ty->isFunctionPointerType() &&
5185       !Ty->isFunctionProtoType())
5186     return false;
5187 
5188   VariadicCallType CallType;
5189   if (!Proto || !Proto->isVariadic()) {
5190     CallType = VariadicDoesNotApply;
5191   } else if (Ty->isBlockPointerType()) {
5192     CallType = VariadicBlock;
5193   } else { // Ty->isFunctionPointerType()
5194     CallType = VariadicFunction;
5195   }
5196 
5197   checkCall(NDecl, Proto, /*ThisArg=*/nullptr,
5198             llvm::makeArrayRef(TheCall->getArgs(), TheCall->getNumArgs()),
5199             /*IsMemberFunction=*/false, TheCall->getRParenLoc(),
5200             TheCall->getCallee()->getSourceRange(), CallType);
5201 
5202   return false;
5203 }
5204 
5205 /// Checks function calls when a FunctionDecl or a NamedDecl is not available,
5206 /// such as function pointers returned from functions.
5207 bool Sema::CheckOtherCall(CallExpr *TheCall, const FunctionProtoType *Proto) {
5208   VariadicCallType CallType = getVariadicCallType(/*FDecl=*/nullptr, Proto,
5209                                                   TheCall->getCallee());
5210   checkCall(/*FDecl=*/nullptr, Proto, /*ThisArg=*/nullptr,
5211             llvm::makeArrayRef(TheCall->getArgs(), TheCall->getNumArgs()),
5212             /*IsMemberFunction=*/false, TheCall->getRParenLoc(),
5213             TheCall->getCallee()->getSourceRange(), CallType);
5214 
5215   return false;
5216 }
5217 
5218 static bool isValidOrderingForOp(int64_t Ordering, AtomicExpr::AtomicOp Op) {
5219   if (!llvm::isValidAtomicOrderingCABI(Ordering))
5220     return false;
5221 
5222   auto OrderingCABI = (llvm::AtomicOrderingCABI)Ordering;
5223   switch (Op) {
5224   case AtomicExpr::AO__c11_atomic_init:
5225   case AtomicExpr::AO__opencl_atomic_init:
5226     llvm_unreachable("There is no ordering argument for an init");
5227 
5228   case AtomicExpr::AO__c11_atomic_load:
5229   case AtomicExpr::AO__opencl_atomic_load:
5230   case AtomicExpr::AO__atomic_load_n:
5231   case AtomicExpr::AO__atomic_load:
5232     return OrderingCABI != llvm::AtomicOrderingCABI::release &&
5233            OrderingCABI != llvm::AtomicOrderingCABI::acq_rel;
5234 
5235   case AtomicExpr::AO__c11_atomic_store:
5236   case AtomicExpr::AO__opencl_atomic_store:
5237   case AtomicExpr::AO__atomic_store:
5238   case AtomicExpr::AO__atomic_store_n:
5239     return OrderingCABI != llvm::AtomicOrderingCABI::consume &&
5240            OrderingCABI != llvm::AtomicOrderingCABI::acquire &&
5241            OrderingCABI != llvm::AtomicOrderingCABI::acq_rel;
5242 
5243   default:
5244     return true;
5245   }
5246 }
5247 
5248 ExprResult Sema::SemaAtomicOpsOverloaded(ExprResult TheCallResult,
5249                                          AtomicExpr::AtomicOp Op) {
5250   CallExpr *TheCall = cast<CallExpr>(TheCallResult.get());
5251   DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts());
5252   MultiExprArg Args{TheCall->getArgs(), TheCall->getNumArgs()};
5253   return BuildAtomicExpr({TheCall->getBeginLoc(), TheCall->getEndLoc()},
5254                          DRE->getSourceRange(), TheCall->getRParenLoc(), Args,
5255                          Op);
5256 }
5257 
5258 ExprResult Sema::BuildAtomicExpr(SourceRange CallRange, SourceRange ExprRange,
5259                                  SourceLocation RParenLoc, MultiExprArg Args,
5260                                  AtomicExpr::AtomicOp Op,
5261                                  AtomicArgumentOrder ArgOrder) {
5262   // All the non-OpenCL operations take one of the following forms.
5263   // The OpenCL operations take the __c11 forms with one extra argument for
5264   // synchronization scope.
5265   enum {
5266     // C    __c11_atomic_init(A *, C)
5267     Init,
5268 
5269     // C    __c11_atomic_load(A *, int)
5270     Load,
5271 
5272     // void __atomic_load(A *, CP, int)
5273     LoadCopy,
5274 
5275     // void __atomic_store(A *, CP, int)
5276     Copy,
5277 
5278     // C    __c11_atomic_add(A *, M, int)
5279     Arithmetic,
5280 
5281     // C    __atomic_exchange_n(A *, CP, int)
5282     Xchg,
5283 
5284     // void __atomic_exchange(A *, C *, CP, int)
5285     GNUXchg,
5286 
5287     // bool __c11_atomic_compare_exchange_strong(A *, C *, CP, int, int)
5288     C11CmpXchg,
5289 
5290     // bool __atomic_compare_exchange(A *, C *, CP, bool, int, int)
5291     GNUCmpXchg
5292   } Form = Init;
5293 
5294   const unsigned NumForm = GNUCmpXchg + 1;
5295   const unsigned NumArgs[] = { 2, 2, 3, 3, 3, 3, 4, 5, 6 };
5296   const unsigned NumVals[] = { 1, 0, 1, 1, 1, 1, 2, 2, 3 };
5297   // where:
5298   //   C is an appropriate type,
5299   //   A is volatile _Atomic(C) for __c11 builtins and is C for GNU builtins,
5300   //   CP is C for __c11 builtins and GNU _n builtins and is C * otherwise,
5301   //   M is C if C is an integer, and ptrdiff_t if C is a pointer, and
5302   //   the int parameters are for orderings.
5303 
5304   static_assert(sizeof(NumArgs)/sizeof(NumArgs[0]) == NumForm
5305       && sizeof(NumVals)/sizeof(NumVals[0]) == NumForm,
5306       "need to update code for modified forms");
5307   static_assert(AtomicExpr::AO__c11_atomic_init == 0 &&
5308                     AtomicExpr::AO__c11_atomic_fetch_min + 1 ==
5309                         AtomicExpr::AO__atomic_load,
5310                 "need to update code for modified C11 atomics");
5311   bool IsOpenCL = Op >= AtomicExpr::AO__opencl_atomic_init &&
5312                   Op <= AtomicExpr::AO__opencl_atomic_fetch_max;
5313   bool IsC11 = (Op >= AtomicExpr::AO__c11_atomic_init &&
5314                Op <= AtomicExpr::AO__c11_atomic_fetch_min) ||
5315                IsOpenCL;
5316   bool IsN = Op == AtomicExpr::AO__atomic_load_n ||
5317              Op == AtomicExpr::AO__atomic_store_n ||
5318              Op == AtomicExpr::AO__atomic_exchange_n ||
5319              Op == AtomicExpr::AO__atomic_compare_exchange_n;
5320   bool IsAddSub = false;
5321 
5322   switch (Op) {
5323   case AtomicExpr::AO__c11_atomic_init:
5324   case AtomicExpr::AO__opencl_atomic_init:
5325     Form = Init;
5326     break;
5327 
5328   case AtomicExpr::AO__c11_atomic_load:
5329   case AtomicExpr::AO__opencl_atomic_load:
5330   case AtomicExpr::AO__atomic_load_n:
5331     Form = Load;
5332     break;
5333 
5334   case AtomicExpr::AO__atomic_load:
5335     Form = LoadCopy;
5336     break;
5337 
5338   case AtomicExpr::AO__c11_atomic_store:
5339   case AtomicExpr::AO__opencl_atomic_store:
5340   case AtomicExpr::AO__atomic_store:
5341   case AtomicExpr::AO__atomic_store_n:
5342     Form = Copy;
5343     break;
5344 
5345   case AtomicExpr::AO__c11_atomic_fetch_add:
5346   case AtomicExpr::AO__c11_atomic_fetch_sub:
5347   case AtomicExpr::AO__opencl_atomic_fetch_add:
5348   case AtomicExpr::AO__opencl_atomic_fetch_sub:
5349   case AtomicExpr::AO__atomic_fetch_add:
5350   case AtomicExpr::AO__atomic_fetch_sub:
5351   case AtomicExpr::AO__atomic_add_fetch:
5352   case AtomicExpr::AO__atomic_sub_fetch:
5353     IsAddSub = true;
5354     Form = Arithmetic;
5355     break;
5356   case AtomicExpr::AO__c11_atomic_fetch_and:
5357   case AtomicExpr::AO__c11_atomic_fetch_or:
5358   case AtomicExpr::AO__c11_atomic_fetch_xor:
5359   case AtomicExpr::AO__opencl_atomic_fetch_and:
5360   case AtomicExpr::AO__opencl_atomic_fetch_or:
5361   case AtomicExpr::AO__opencl_atomic_fetch_xor:
5362   case AtomicExpr::AO__atomic_fetch_and:
5363   case AtomicExpr::AO__atomic_fetch_or:
5364   case AtomicExpr::AO__atomic_fetch_xor:
5365   case AtomicExpr::AO__atomic_fetch_nand:
5366   case AtomicExpr::AO__atomic_and_fetch:
5367   case AtomicExpr::AO__atomic_or_fetch:
5368   case AtomicExpr::AO__atomic_xor_fetch:
5369   case AtomicExpr::AO__atomic_nand_fetch:
5370     Form = Arithmetic;
5371     break;
5372   case AtomicExpr::AO__c11_atomic_fetch_min:
5373   case AtomicExpr::AO__c11_atomic_fetch_max:
5374   case AtomicExpr::AO__opencl_atomic_fetch_min:
5375   case AtomicExpr::AO__opencl_atomic_fetch_max:
5376   case AtomicExpr::AO__atomic_min_fetch:
5377   case AtomicExpr::AO__atomic_max_fetch:
5378   case AtomicExpr::AO__atomic_fetch_min:
5379   case AtomicExpr::AO__atomic_fetch_max:
5380     Form = Arithmetic;
5381     break;
5382 
5383   case AtomicExpr::AO__c11_atomic_exchange:
5384   case AtomicExpr::AO__opencl_atomic_exchange:
5385   case AtomicExpr::AO__atomic_exchange_n:
5386     Form = Xchg;
5387     break;
5388 
5389   case AtomicExpr::AO__atomic_exchange:
5390     Form = GNUXchg;
5391     break;
5392 
5393   case AtomicExpr::AO__c11_atomic_compare_exchange_strong:
5394   case AtomicExpr::AO__c11_atomic_compare_exchange_weak:
5395   case AtomicExpr::AO__opencl_atomic_compare_exchange_strong:
5396   case AtomicExpr::AO__opencl_atomic_compare_exchange_weak:
5397     Form = C11CmpXchg;
5398     break;
5399 
5400   case AtomicExpr::AO__atomic_compare_exchange:
5401   case AtomicExpr::AO__atomic_compare_exchange_n:
5402     Form = GNUCmpXchg;
5403     break;
5404   }
5405 
5406   unsigned AdjustedNumArgs = NumArgs[Form];
5407   if (IsOpenCL && Op != AtomicExpr::AO__opencl_atomic_init)
5408     ++AdjustedNumArgs;
5409   // Check we have the right number of arguments.
5410   if (Args.size() < AdjustedNumArgs) {
5411     Diag(CallRange.getEnd(), diag::err_typecheck_call_too_few_args)
5412         << 0 << AdjustedNumArgs << static_cast<unsigned>(Args.size())
5413         << ExprRange;
5414     return ExprError();
5415   } else if (Args.size() > AdjustedNumArgs) {
5416     Diag(Args[AdjustedNumArgs]->getBeginLoc(),
5417          diag::err_typecheck_call_too_many_args)
5418         << 0 << AdjustedNumArgs << static_cast<unsigned>(Args.size())
5419         << ExprRange;
5420     return ExprError();
5421   }
5422 
5423   // Inspect the first argument of the atomic operation.
5424   Expr *Ptr = Args[0];
5425   ExprResult ConvertedPtr = DefaultFunctionArrayLvalueConversion(Ptr);
5426   if (ConvertedPtr.isInvalid())
5427     return ExprError();
5428 
5429   Ptr = ConvertedPtr.get();
5430   const PointerType *pointerType = Ptr->getType()->getAs<PointerType>();
5431   if (!pointerType) {
5432     Diag(ExprRange.getBegin(), diag::err_atomic_builtin_must_be_pointer)
5433         << Ptr->getType() << Ptr->getSourceRange();
5434     return ExprError();
5435   }
5436 
5437   // For a __c11 builtin, this should be a pointer to an _Atomic type.
5438   QualType AtomTy = pointerType->getPointeeType(); // 'A'
5439   QualType ValType = AtomTy; // 'C'
5440   if (IsC11) {
5441     if (!AtomTy->isAtomicType()) {
5442       Diag(ExprRange.getBegin(), diag::err_atomic_op_needs_atomic)
5443           << Ptr->getType() << Ptr->getSourceRange();
5444       return ExprError();
5445     }
5446     if ((Form != Load && Form != LoadCopy && AtomTy.isConstQualified()) ||
5447         AtomTy.getAddressSpace() == LangAS::opencl_constant) {
5448       Diag(ExprRange.getBegin(), diag::err_atomic_op_needs_non_const_atomic)
5449           << (AtomTy.isConstQualified() ? 0 : 1) << Ptr->getType()
5450           << Ptr->getSourceRange();
5451       return ExprError();
5452     }
5453     ValType = AtomTy->castAs<AtomicType>()->getValueType();
5454   } else if (Form != Load && Form != LoadCopy) {
5455     if (ValType.isConstQualified()) {
5456       Diag(ExprRange.getBegin(), diag::err_atomic_op_needs_non_const_pointer)
5457           << Ptr->getType() << Ptr->getSourceRange();
5458       return ExprError();
5459     }
5460   }
5461 
5462   // For an arithmetic operation, the implied arithmetic must be well-formed.
5463   if (Form == Arithmetic) {
5464     // gcc does not enforce these rules for GNU atomics, but we do so for
5465     // sanity.
5466     auto IsAllowedValueType = [&](QualType ValType) {
5467       if (ValType->isIntegerType())
5468         return true;
5469       if (ValType->isPointerType())
5470         return true;
5471       if (!ValType->isFloatingType())
5472         return false;
5473       // LLVM Parser does not allow atomicrmw with x86_fp80 type.
5474       if (ValType->isSpecificBuiltinType(BuiltinType::LongDouble) &&
5475           &Context.getTargetInfo().getLongDoubleFormat() ==
5476               &llvm::APFloat::x87DoubleExtended())
5477         return false;
5478       return true;
5479     };
5480     if (IsAddSub && !IsAllowedValueType(ValType)) {
5481       Diag(ExprRange.getBegin(), diag::err_atomic_op_needs_atomic_int_ptr_or_fp)
5482           << IsC11 << Ptr->getType() << Ptr->getSourceRange();
5483       return ExprError();
5484     }
5485     if (!IsAddSub && !ValType->isIntegerType()) {
5486       Diag(ExprRange.getBegin(), diag::err_atomic_op_needs_atomic_int)
5487           << IsC11 << Ptr->getType() << Ptr->getSourceRange();
5488       return ExprError();
5489     }
5490     if (IsC11 && ValType->isPointerType() &&
5491         RequireCompleteType(Ptr->getBeginLoc(), ValType->getPointeeType(),
5492                             diag::err_incomplete_type)) {
5493       return ExprError();
5494     }
5495   } else if (IsN && !ValType->isIntegerType() && !ValType->isPointerType()) {
5496     // For __atomic_*_n operations, the value type must be a scalar integral or
5497     // pointer type which is 1, 2, 4, 8 or 16 bytes in length.
5498     Diag(ExprRange.getBegin(), diag::err_atomic_op_needs_atomic_int_or_ptr)
5499         << IsC11 << Ptr->getType() << Ptr->getSourceRange();
5500     return ExprError();
5501   }
5502 
5503   if (!IsC11 && !AtomTy.isTriviallyCopyableType(Context) &&
5504       !AtomTy->isScalarType()) {
5505     // For GNU atomics, require a trivially-copyable type. This is not part of
5506     // the GNU atomics specification, but we enforce it for sanity.
5507     Diag(ExprRange.getBegin(), diag::err_atomic_op_needs_trivial_copy)
5508         << Ptr->getType() << Ptr->getSourceRange();
5509     return ExprError();
5510   }
5511 
5512   switch (ValType.getObjCLifetime()) {
5513   case Qualifiers::OCL_None:
5514   case Qualifiers::OCL_ExplicitNone:
5515     // okay
5516     break;
5517 
5518   case Qualifiers::OCL_Weak:
5519   case Qualifiers::OCL_Strong:
5520   case Qualifiers::OCL_Autoreleasing:
5521     // FIXME: Can this happen? By this point, ValType should be known
5522     // to be trivially copyable.
5523     Diag(ExprRange.getBegin(), diag::err_arc_atomic_ownership)
5524         << ValType << Ptr->getSourceRange();
5525     return ExprError();
5526   }
5527 
5528   // All atomic operations have an overload which takes a pointer to a volatile
5529   // 'A'.  We shouldn't let the volatile-ness of the pointee-type inject itself
5530   // into the result or the other operands. Similarly atomic_load takes a
5531   // pointer to a const 'A'.
5532   ValType.removeLocalVolatile();
5533   ValType.removeLocalConst();
5534   QualType ResultType = ValType;
5535   if (Form == Copy || Form == LoadCopy || Form == GNUXchg ||
5536       Form == Init)
5537     ResultType = Context.VoidTy;
5538   else if (Form == C11CmpXchg || Form == GNUCmpXchg)
5539     ResultType = Context.BoolTy;
5540 
5541   // The type of a parameter passed 'by value'. In the GNU atomics, such
5542   // arguments are actually passed as pointers.
5543   QualType ByValType = ValType; // 'CP'
5544   bool IsPassedByAddress = false;
5545   if (!IsC11 && !IsN) {
5546     ByValType = Ptr->getType();
5547     IsPassedByAddress = true;
5548   }
5549 
5550   SmallVector<Expr *, 5> APIOrderedArgs;
5551   if (ArgOrder == Sema::AtomicArgumentOrder::AST) {
5552     APIOrderedArgs.push_back(Args[0]);
5553     switch (Form) {
5554     case Init:
5555     case Load:
5556       APIOrderedArgs.push_back(Args[1]); // Val1/Order
5557       break;
5558     case LoadCopy:
5559     case Copy:
5560     case Arithmetic:
5561     case Xchg:
5562       APIOrderedArgs.push_back(Args[2]); // Val1
5563       APIOrderedArgs.push_back(Args[1]); // Order
5564       break;
5565     case GNUXchg:
5566       APIOrderedArgs.push_back(Args[2]); // Val1
5567       APIOrderedArgs.push_back(Args[3]); // Val2
5568       APIOrderedArgs.push_back(Args[1]); // Order
5569       break;
5570     case C11CmpXchg:
5571       APIOrderedArgs.push_back(Args[2]); // Val1
5572       APIOrderedArgs.push_back(Args[4]); // Val2
5573       APIOrderedArgs.push_back(Args[1]); // Order
5574       APIOrderedArgs.push_back(Args[3]); // OrderFail
5575       break;
5576     case GNUCmpXchg:
5577       APIOrderedArgs.push_back(Args[2]); // Val1
5578       APIOrderedArgs.push_back(Args[4]); // Val2
5579       APIOrderedArgs.push_back(Args[5]); // Weak
5580       APIOrderedArgs.push_back(Args[1]); // Order
5581       APIOrderedArgs.push_back(Args[3]); // OrderFail
5582       break;
5583     }
5584   } else
5585     APIOrderedArgs.append(Args.begin(), Args.end());
5586 
5587   // The first argument's non-CV pointer type is used to deduce the type of
5588   // subsequent arguments, except for:
5589   //  - weak flag (always converted to bool)
5590   //  - memory order (always converted to int)
5591   //  - scope  (always converted to int)
5592   for (unsigned i = 0; i != APIOrderedArgs.size(); ++i) {
5593     QualType Ty;
5594     if (i < NumVals[Form] + 1) {
5595       switch (i) {
5596       case 0:
5597         // The first argument is always a pointer. It has a fixed type.
5598         // It is always dereferenced, a nullptr is undefined.
5599         CheckNonNullArgument(*this, APIOrderedArgs[i], ExprRange.getBegin());
5600         // Nothing else to do: we already know all we want about this pointer.
5601         continue;
5602       case 1:
5603         // The second argument is the non-atomic operand. For arithmetic, this
5604         // is always passed by value, and for a compare_exchange it is always
5605         // passed by address. For the rest, GNU uses by-address and C11 uses
5606         // by-value.
5607         assert(Form != Load);
5608         if (Form == Arithmetic && ValType->isPointerType())
5609           Ty = Context.getPointerDiffType();
5610         else if (Form == Init || Form == Arithmetic)
5611           Ty = ValType;
5612         else if (Form == Copy || Form == Xchg) {
5613           if (IsPassedByAddress) {
5614             // The value pointer is always dereferenced, a nullptr is undefined.
5615             CheckNonNullArgument(*this, APIOrderedArgs[i],
5616                                  ExprRange.getBegin());
5617           }
5618           Ty = ByValType;
5619         } else {
5620           Expr *ValArg = APIOrderedArgs[i];
5621           // The value pointer is always dereferenced, a nullptr is undefined.
5622           CheckNonNullArgument(*this, ValArg, ExprRange.getBegin());
5623           LangAS AS = LangAS::Default;
5624           // Keep address space of non-atomic pointer type.
5625           if (const PointerType *PtrTy =
5626                   ValArg->getType()->getAs<PointerType>()) {
5627             AS = PtrTy->getPointeeType().getAddressSpace();
5628           }
5629           Ty = Context.getPointerType(
5630               Context.getAddrSpaceQualType(ValType.getUnqualifiedType(), AS));
5631         }
5632         break;
5633       case 2:
5634         // The third argument to compare_exchange / GNU exchange is the desired
5635         // value, either by-value (for the C11 and *_n variant) or as a pointer.
5636         if (IsPassedByAddress)
5637           CheckNonNullArgument(*this, APIOrderedArgs[i], ExprRange.getBegin());
5638         Ty = ByValType;
5639         break;
5640       case 3:
5641         // The fourth argument to GNU compare_exchange is a 'weak' flag.
5642         Ty = Context.BoolTy;
5643         break;
5644       }
5645     } else {
5646       // The order(s) and scope are always converted to int.
5647       Ty = Context.IntTy;
5648     }
5649 
5650     InitializedEntity Entity =
5651         InitializedEntity::InitializeParameter(Context, Ty, false);
5652     ExprResult Arg = APIOrderedArgs[i];
5653     Arg = PerformCopyInitialization(Entity, SourceLocation(), Arg);
5654     if (Arg.isInvalid())
5655       return true;
5656     APIOrderedArgs[i] = Arg.get();
5657   }
5658 
5659   // Permute the arguments into a 'consistent' order.
5660   SmallVector<Expr*, 5> SubExprs;
5661   SubExprs.push_back(Ptr);
5662   switch (Form) {
5663   case Init:
5664     // Note, AtomicExpr::getVal1() has a special case for this atomic.
5665     SubExprs.push_back(APIOrderedArgs[1]); // Val1
5666     break;
5667   case Load:
5668     SubExprs.push_back(APIOrderedArgs[1]); // Order
5669     break;
5670   case LoadCopy:
5671   case Copy:
5672   case Arithmetic:
5673   case Xchg:
5674     SubExprs.push_back(APIOrderedArgs[2]); // Order
5675     SubExprs.push_back(APIOrderedArgs[1]); // Val1
5676     break;
5677   case GNUXchg:
5678     // Note, AtomicExpr::getVal2() has a special case for this atomic.
5679     SubExprs.push_back(APIOrderedArgs[3]); // Order
5680     SubExprs.push_back(APIOrderedArgs[1]); // Val1
5681     SubExprs.push_back(APIOrderedArgs[2]); // Val2
5682     break;
5683   case C11CmpXchg:
5684     SubExprs.push_back(APIOrderedArgs[3]); // Order
5685     SubExprs.push_back(APIOrderedArgs[1]); // Val1
5686     SubExprs.push_back(APIOrderedArgs[4]); // OrderFail
5687     SubExprs.push_back(APIOrderedArgs[2]); // Val2
5688     break;
5689   case GNUCmpXchg:
5690     SubExprs.push_back(APIOrderedArgs[4]); // Order
5691     SubExprs.push_back(APIOrderedArgs[1]); // Val1
5692     SubExprs.push_back(APIOrderedArgs[5]); // OrderFail
5693     SubExprs.push_back(APIOrderedArgs[2]); // Val2
5694     SubExprs.push_back(APIOrderedArgs[3]); // Weak
5695     break;
5696   }
5697 
5698   if (SubExprs.size() >= 2 && Form != Init) {
5699     if (Optional<llvm::APSInt> Result =
5700             SubExprs[1]->getIntegerConstantExpr(Context))
5701       if (!isValidOrderingForOp(Result->getSExtValue(), Op))
5702         Diag(SubExprs[1]->getBeginLoc(),
5703              diag::warn_atomic_op_has_invalid_memory_order)
5704             << SubExprs[1]->getSourceRange();
5705   }
5706 
5707   if (auto ScopeModel = AtomicExpr::getScopeModel(Op)) {
5708     auto *Scope = Args[Args.size() - 1];
5709     if (Optional<llvm::APSInt> Result =
5710             Scope->getIntegerConstantExpr(Context)) {
5711       if (!ScopeModel->isValid(Result->getZExtValue()))
5712         Diag(Scope->getBeginLoc(), diag::err_atomic_op_has_invalid_synch_scope)
5713             << Scope->getSourceRange();
5714     }
5715     SubExprs.push_back(Scope);
5716   }
5717 
5718   AtomicExpr *AE = new (Context)
5719       AtomicExpr(ExprRange.getBegin(), SubExprs, ResultType, Op, RParenLoc);
5720 
5721   if ((Op == AtomicExpr::AO__c11_atomic_load ||
5722        Op == AtomicExpr::AO__c11_atomic_store ||
5723        Op == AtomicExpr::AO__opencl_atomic_load ||
5724        Op == AtomicExpr::AO__opencl_atomic_store ) &&
5725       Context.AtomicUsesUnsupportedLibcall(AE))
5726     Diag(AE->getBeginLoc(), diag::err_atomic_load_store_uses_lib)
5727         << ((Op == AtomicExpr::AO__c11_atomic_load ||
5728              Op == AtomicExpr::AO__opencl_atomic_load)
5729                 ? 0
5730                 : 1);
5731 
5732   if (ValType->isExtIntType()) {
5733     Diag(Ptr->getExprLoc(), diag::err_atomic_builtin_ext_int_prohibit);
5734     return ExprError();
5735   }
5736 
5737   return AE;
5738 }
5739 
5740 /// checkBuiltinArgument - Given a call to a builtin function, perform
5741 /// normal type-checking on the given argument, updating the call in
5742 /// place.  This is useful when a builtin function requires custom
5743 /// type-checking for some of its arguments but not necessarily all of
5744 /// them.
5745 ///
5746 /// Returns true on error.
5747 static bool checkBuiltinArgument(Sema &S, CallExpr *E, unsigned ArgIndex) {
5748   FunctionDecl *Fn = E->getDirectCallee();
5749   assert(Fn && "builtin call without direct callee!");
5750 
5751   ParmVarDecl *Param = Fn->getParamDecl(ArgIndex);
5752   InitializedEntity Entity =
5753     InitializedEntity::InitializeParameter(S.Context, Param);
5754 
5755   ExprResult Arg = E->getArg(0);
5756   Arg = S.PerformCopyInitialization(Entity, SourceLocation(), Arg);
5757   if (Arg.isInvalid())
5758     return true;
5759 
5760   E->setArg(ArgIndex, Arg.get());
5761   return false;
5762 }
5763 
5764 /// We have a call to a function like __sync_fetch_and_add, which is an
5765 /// overloaded function based on the pointer type of its first argument.
5766 /// The main BuildCallExpr routines have already promoted the types of
5767 /// arguments because all of these calls are prototyped as void(...).
5768 ///
5769 /// This function goes through and does final semantic checking for these
5770 /// builtins, as well as generating any warnings.
5771 ExprResult
5772 Sema::SemaBuiltinAtomicOverloaded(ExprResult TheCallResult) {
5773   CallExpr *TheCall = static_cast<CallExpr *>(TheCallResult.get());
5774   Expr *Callee = TheCall->getCallee();
5775   DeclRefExpr *DRE = cast<DeclRefExpr>(Callee->IgnoreParenCasts());
5776   FunctionDecl *FDecl = cast<FunctionDecl>(DRE->getDecl());
5777 
5778   // Ensure that we have at least one argument to do type inference from.
5779   if (TheCall->getNumArgs() < 1) {
5780     Diag(TheCall->getEndLoc(), diag::err_typecheck_call_too_few_args_at_least)
5781         << 0 << 1 << TheCall->getNumArgs() << Callee->getSourceRange();
5782     return ExprError();
5783   }
5784 
5785   // Inspect the first argument of the atomic builtin.  This should always be
5786   // a pointer type, whose element is an integral scalar or pointer type.
5787   // Because it is a pointer type, we don't have to worry about any implicit
5788   // casts here.
5789   // FIXME: We don't allow floating point scalars as input.
5790   Expr *FirstArg = TheCall->getArg(0);
5791   ExprResult FirstArgResult = DefaultFunctionArrayLvalueConversion(FirstArg);
5792   if (FirstArgResult.isInvalid())
5793     return ExprError();
5794   FirstArg = FirstArgResult.get();
5795   TheCall->setArg(0, FirstArg);
5796 
5797   const PointerType *pointerType = FirstArg->getType()->getAs<PointerType>();
5798   if (!pointerType) {
5799     Diag(DRE->getBeginLoc(), diag::err_atomic_builtin_must_be_pointer)
5800         << FirstArg->getType() << FirstArg->getSourceRange();
5801     return ExprError();
5802   }
5803 
5804   QualType ValType = pointerType->getPointeeType();
5805   if (!ValType->isIntegerType() && !ValType->isAnyPointerType() &&
5806       !ValType->isBlockPointerType()) {
5807     Diag(DRE->getBeginLoc(), diag::err_atomic_builtin_must_be_pointer_intptr)
5808         << FirstArg->getType() << FirstArg->getSourceRange();
5809     return ExprError();
5810   }
5811 
5812   if (ValType.isConstQualified()) {
5813     Diag(DRE->getBeginLoc(), diag::err_atomic_builtin_cannot_be_const)
5814         << FirstArg->getType() << FirstArg->getSourceRange();
5815     return ExprError();
5816   }
5817 
5818   switch (ValType.getObjCLifetime()) {
5819   case Qualifiers::OCL_None:
5820   case Qualifiers::OCL_ExplicitNone:
5821     // okay
5822     break;
5823 
5824   case Qualifiers::OCL_Weak:
5825   case Qualifiers::OCL_Strong:
5826   case Qualifiers::OCL_Autoreleasing:
5827     Diag(DRE->getBeginLoc(), diag::err_arc_atomic_ownership)
5828         << ValType << FirstArg->getSourceRange();
5829     return ExprError();
5830   }
5831 
5832   // Strip any qualifiers off ValType.
5833   ValType = ValType.getUnqualifiedType();
5834 
5835   // The majority of builtins return a value, but a few have special return
5836   // types, so allow them to override appropriately below.
5837   QualType ResultType = ValType;
5838 
5839   // We need to figure out which concrete builtin this maps onto.  For example,
5840   // __sync_fetch_and_add with a 2 byte object turns into
5841   // __sync_fetch_and_add_2.
5842 #define BUILTIN_ROW(x) \
5843   { Builtin::BI##x##_1, Builtin::BI##x##_2, Builtin::BI##x##_4, \
5844     Builtin::BI##x##_8, Builtin::BI##x##_16 }
5845 
5846   static const unsigned BuiltinIndices[][5] = {
5847     BUILTIN_ROW(__sync_fetch_and_add),
5848     BUILTIN_ROW(__sync_fetch_and_sub),
5849     BUILTIN_ROW(__sync_fetch_and_or),
5850     BUILTIN_ROW(__sync_fetch_and_and),
5851     BUILTIN_ROW(__sync_fetch_and_xor),
5852     BUILTIN_ROW(__sync_fetch_and_nand),
5853 
5854     BUILTIN_ROW(__sync_add_and_fetch),
5855     BUILTIN_ROW(__sync_sub_and_fetch),
5856     BUILTIN_ROW(__sync_and_and_fetch),
5857     BUILTIN_ROW(__sync_or_and_fetch),
5858     BUILTIN_ROW(__sync_xor_and_fetch),
5859     BUILTIN_ROW(__sync_nand_and_fetch),
5860 
5861     BUILTIN_ROW(__sync_val_compare_and_swap),
5862     BUILTIN_ROW(__sync_bool_compare_and_swap),
5863     BUILTIN_ROW(__sync_lock_test_and_set),
5864     BUILTIN_ROW(__sync_lock_release),
5865     BUILTIN_ROW(__sync_swap)
5866   };
5867 #undef BUILTIN_ROW
5868 
5869   // Determine the index of the size.
5870   unsigned SizeIndex;
5871   switch (Context.getTypeSizeInChars(ValType).getQuantity()) {
5872   case 1: SizeIndex = 0; break;
5873   case 2: SizeIndex = 1; break;
5874   case 4: SizeIndex = 2; break;
5875   case 8: SizeIndex = 3; break;
5876   case 16: SizeIndex = 4; break;
5877   default:
5878     Diag(DRE->getBeginLoc(), diag::err_atomic_builtin_pointer_size)
5879         << FirstArg->getType() << FirstArg->getSourceRange();
5880     return ExprError();
5881   }
5882 
5883   // Each of these builtins has one pointer argument, followed by some number of
5884   // values (0, 1 or 2) followed by a potentially empty varags list of stuff
5885   // that we ignore.  Find out which row of BuiltinIndices to read from as well
5886   // as the number of fixed args.
5887   unsigned BuiltinID = FDecl->getBuiltinID();
5888   unsigned BuiltinIndex, NumFixed = 1;
5889   bool WarnAboutSemanticsChange = false;
5890   switch (BuiltinID) {
5891   default: llvm_unreachable("Unknown overloaded atomic builtin!");
5892   case Builtin::BI__sync_fetch_and_add:
5893   case Builtin::BI__sync_fetch_and_add_1:
5894   case Builtin::BI__sync_fetch_and_add_2:
5895   case Builtin::BI__sync_fetch_and_add_4:
5896   case Builtin::BI__sync_fetch_and_add_8:
5897   case Builtin::BI__sync_fetch_and_add_16:
5898     BuiltinIndex = 0;
5899     break;
5900 
5901   case Builtin::BI__sync_fetch_and_sub:
5902   case Builtin::BI__sync_fetch_and_sub_1:
5903   case Builtin::BI__sync_fetch_and_sub_2:
5904   case Builtin::BI__sync_fetch_and_sub_4:
5905   case Builtin::BI__sync_fetch_and_sub_8:
5906   case Builtin::BI__sync_fetch_and_sub_16:
5907     BuiltinIndex = 1;
5908     break;
5909 
5910   case Builtin::BI__sync_fetch_and_or:
5911   case Builtin::BI__sync_fetch_and_or_1:
5912   case Builtin::BI__sync_fetch_and_or_2:
5913   case Builtin::BI__sync_fetch_and_or_4:
5914   case Builtin::BI__sync_fetch_and_or_8:
5915   case Builtin::BI__sync_fetch_and_or_16:
5916     BuiltinIndex = 2;
5917     break;
5918 
5919   case Builtin::BI__sync_fetch_and_and:
5920   case Builtin::BI__sync_fetch_and_and_1:
5921   case Builtin::BI__sync_fetch_and_and_2:
5922   case Builtin::BI__sync_fetch_and_and_4:
5923   case Builtin::BI__sync_fetch_and_and_8:
5924   case Builtin::BI__sync_fetch_and_and_16:
5925     BuiltinIndex = 3;
5926     break;
5927 
5928   case Builtin::BI__sync_fetch_and_xor:
5929   case Builtin::BI__sync_fetch_and_xor_1:
5930   case Builtin::BI__sync_fetch_and_xor_2:
5931   case Builtin::BI__sync_fetch_and_xor_4:
5932   case Builtin::BI__sync_fetch_and_xor_8:
5933   case Builtin::BI__sync_fetch_and_xor_16:
5934     BuiltinIndex = 4;
5935     break;
5936 
5937   case Builtin::BI__sync_fetch_and_nand:
5938   case Builtin::BI__sync_fetch_and_nand_1:
5939   case Builtin::BI__sync_fetch_and_nand_2:
5940   case Builtin::BI__sync_fetch_and_nand_4:
5941   case Builtin::BI__sync_fetch_and_nand_8:
5942   case Builtin::BI__sync_fetch_and_nand_16:
5943     BuiltinIndex = 5;
5944     WarnAboutSemanticsChange = true;
5945     break;
5946 
5947   case Builtin::BI__sync_add_and_fetch:
5948   case Builtin::BI__sync_add_and_fetch_1:
5949   case Builtin::BI__sync_add_and_fetch_2:
5950   case Builtin::BI__sync_add_and_fetch_4:
5951   case Builtin::BI__sync_add_and_fetch_8:
5952   case Builtin::BI__sync_add_and_fetch_16:
5953     BuiltinIndex = 6;
5954     break;
5955 
5956   case Builtin::BI__sync_sub_and_fetch:
5957   case Builtin::BI__sync_sub_and_fetch_1:
5958   case Builtin::BI__sync_sub_and_fetch_2:
5959   case Builtin::BI__sync_sub_and_fetch_4:
5960   case Builtin::BI__sync_sub_and_fetch_8:
5961   case Builtin::BI__sync_sub_and_fetch_16:
5962     BuiltinIndex = 7;
5963     break;
5964 
5965   case Builtin::BI__sync_and_and_fetch:
5966   case Builtin::BI__sync_and_and_fetch_1:
5967   case Builtin::BI__sync_and_and_fetch_2:
5968   case Builtin::BI__sync_and_and_fetch_4:
5969   case Builtin::BI__sync_and_and_fetch_8:
5970   case Builtin::BI__sync_and_and_fetch_16:
5971     BuiltinIndex = 8;
5972     break;
5973 
5974   case Builtin::BI__sync_or_and_fetch:
5975   case Builtin::BI__sync_or_and_fetch_1:
5976   case Builtin::BI__sync_or_and_fetch_2:
5977   case Builtin::BI__sync_or_and_fetch_4:
5978   case Builtin::BI__sync_or_and_fetch_8:
5979   case Builtin::BI__sync_or_and_fetch_16:
5980     BuiltinIndex = 9;
5981     break;
5982 
5983   case Builtin::BI__sync_xor_and_fetch:
5984   case Builtin::BI__sync_xor_and_fetch_1:
5985   case Builtin::BI__sync_xor_and_fetch_2:
5986   case Builtin::BI__sync_xor_and_fetch_4:
5987   case Builtin::BI__sync_xor_and_fetch_8:
5988   case Builtin::BI__sync_xor_and_fetch_16:
5989     BuiltinIndex = 10;
5990     break;
5991 
5992   case Builtin::BI__sync_nand_and_fetch:
5993   case Builtin::BI__sync_nand_and_fetch_1:
5994   case Builtin::BI__sync_nand_and_fetch_2:
5995   case Builtin::BI__sync_nand_and_fetch_4:
5996   case Builtin::BI__sync_nand_and_fetch_8:
5997   case Builtin::BI__sync_nand_and_fetch_16:
5998     BuiltinIndex = 11;
5999     WarnAboutSemanticsChange = true;
6000     break;
6001 
6002   case Builtin::BI__sync_val_compare_and_swap:
6003   case Builtin::BI__sync_val_compare_and_swap_1:
6004   case Builtin::BI__sync_val_compare_and_swap_2:
6005   case Builtin::BI__sync_val_compare_and_swap_4:
6006   case Builtin::BI__sync_val_compare_and_swap_8:
6007   case Builtin::BI__sync_val_compare_and_swap_16:
6008     BuiltinIndex = 12;
6009     NumFixed = 2;
6010     break;
6011 
6012   case Builtin::BI__sync_bool_compare_and_swap:
6013   case Builtin::BI__sync_bool_compare_and_swap_1:
6014   case Builtin::BI__sync_bool_compare_and_swap_2:
6015   case Builtin::BI__sync_bool_compare_and_swap_4:
6016   case Builtin::BI__sync_bool_compare_and_swap_8:
6017   case Builtin::BI__sync_bool_compare_and_swap_16:
6018     BuiltinIndex = 13;
6019     NumFixed = 2;
6020     ResultType = Context.BoolTy;
6021     break;
6022 
6023   case Builtin::BI__sync_lock_test_and_set:
6024   case Builtin::BI__sync_lock_test_and_set_1:
6025   case Builtin::BI__sync_lock_test_and_set_2:
6026   case Builtin::BI__sync_lock_test_and_set_4:
6027   case Builtin::BI__sync_lock_test_and_set_8:
6028   case Builtin::BI__sync_lock_test_and_set_16:
6029     BuiltinIndex = 14;
6030     break;
6031 
6032   case Builtin::BI__sync_lock_release:
6033   case Builtin::BI__sync_lock_release_1:
6034   case Builtin::BI__sync_lock_release_2:
6035   case Builtin::BI__sync_lock_release_4:
6036   case Builtin::BI__sync_lock_release_8:
6037   case Builtin::BI__sync_lock_release_16:
6038     BuiltinIndex = 15;
6039     NumFixed = 0;
6040     ResultType = Context.VoidTy;
6041     break;
6042 
6043   case Builtin::BI__sync_swap:
6044   case Builtin::BI__sync_swap_1:
6045   case Builtin::BI__sync_swap_2:
6046   case Builtin::BI__sync_swap_4:
6047   case Builtin::BI__sync_swap_8:
6048   case Builtin::BI__sync_swap_16:
6049     BuiltinIndex = 16;
6050     break;
6051   }
6052 
6053   // Now that we know how many fixed arguments we expect, first check that we
6054   // have at least that many.
6055   if (TheCall->getNumArgs() < 1+NumFixed) {
6056     Diag(TheCall->getEndLoc(), diag::err_typecheck_call_too_few_args_at_least)
6057         << 0 << 1 + NumFixed << TheCall->getNumArgs()
6058         << Callee->getSourceRange();
6059     return ExprError();
6060   }
6061 
6062   Diag(TheCall->getEndLoc(), diag::warn_atomic_implicit_seq_cst)
6063       << Callee->getSourceRange();
6064 
6065   if (WarnAboutSemanticsChange) {
6066     Diag(TheCall->getEndLoc(), diag::warn_sync_fetch_and_nand_semantics_change)
6067         << Callee->getSourceRange();
6068   }
6069 
6070   // Get the decl for the concrete builtin from this, we can tell what the
6071   // concrete integer type we should convert to is.
6072   unsigned NewBuiltinID = BuiltinIndices[BuiltinIndex][SizeIndex];
6073   const char *NewBuiltinName = Context.BuiltinInfo.getName(NewBuiltinID);
6074   FunctionDecl *NewBuiltinDecl;
6075   if (NewBuiltinID == BuiltinID)
6076     NewBuiltinDecl = FDecl;
6077   else {
6078     // Perform builtin lookup to avoid redeclaring it.
6079     DeclarationName DN(&Context.Idents.get(NewBuiltinName));
6080     LookupResult Res(*this, DN, DRE->getBeginLoc(), LookupOrdinaryName);
6081     LookupName(Res, TUScope, /*AllowBuiltinCreation=*/true);
6082     assert(Res.getFoundDecl());
6083     NewBuiltinDecl = dyn_cast<FunctionDecl>(Res.getFoundDecl());
6084     if (!NewBuiltinDecl)
6085       return ExprError();
6086   }
6087 
6088   // The first argument --- the pointer --- has a fixed type; we
6089   // deduce the types of the rest of the arguments accordingly.  Walk
6090   // the remaining arguments, converting them to the deduced value type.
6091   for (unsigned i = 0; i != NumFixed; ++i) {
6092     ExprResult Arg = TheCall->getArg(i+1);
6093 
6094     // GCC does an implicit conversion to the pointer or integer ValType.  This
6095     // can fail in some cases (1i -> int**), check for this error case now.
6096     // Initialize the argument.
6097     InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
6098                                                    ValType, /*consume*/ false);
6099     Arg = PerformCopyInitialization(Entity, SourceLocation(), Arg);
6100     if (Arg.isInvalid())
6101       return ExprError();
6102 
6103     // Okay, we have something that *can* be converted to the right type.  Check
6104     // to see if there is a potentially weird extension going on here.  This can
6105     // happen when you do an atomic operation on something like an char* and
6106     // pass in 42.  The 42 gets converted to char.  This is even more strange
6107     // for things like 45.123 -> char, etc.
6108     // FIXME: Do this check.
6109     TheCall->setArg(i+1, Arg.get());
6110   }
6111 
6112   // Create a new DeclRefExpr to refer to the new decl.
6113   DeclRefExpr *NewDRE = DeclRefExpr::Create(
6114       Context, DRE->getQualifierLoc(), SourceLocation(), NewBuiltinDecl,
6115       /*enclosing*/ false, DRE->getLocation(), Context.BuiltinFnTy,
6116       DRE->getValueKind(), nullptr, nullptr, DRE->isNonOdrUse());
6117 
6118   // Set the callee in the CallExpr.
6119   // FIXME: This loses syntactic information.
6120   QualType CalleePtrTy = Context.getPointerType(NewBuiltinDecl->getType());
6121   ExprResult PromotedCall = ImpCastExprToType(NewDRE, CalleePtrTy,
6122                                               CK_BuiltinFnToFnPtr);
6123   TheCall->setCallee(PromotedCall.get());
6124 
6125   // Change the result type of the call to match the original value type. This
6126   // is arbitrary, but the codegen for these builtins ins design to handle it
6127   // gracefully.
6128   TheCall->setType(ResultType);
6129 
6130   // Prohibit use of _ExtInt with atomic builtins.
6131   // The arguments would have already been converted to the first argument's
6132   // type, so only need to check the first argument.
6133   const auto *ExtIntValType = ValType->getAs<ExtIntType>();
6134   if (ExtIntValType && !llvm::isPowerOf2_64(ExtIntValType->getNumBits())) {
6135     Diag(FirstArg->getExprLoc(), diag::err_atomic_builtin_ext_int_size);
6136     return ExprError();
6137   }
6138 
6139   return TheCallResult;
6140 }
6141 
6142 /// SemaBuiltinNontemporalOverloaded - We have a call to
6143 /// __builtin_nontemporal_store or __builtin_nontemporal_load, which is an
6144 /// overloaded function based on the pointer type of its last argument.
6145 ///
6146 /// This function goes through and does final semantic checking for these
6147 /// builtins.
6148 ExprResult Sema::SemaBuiltinNontemporalOverloaded(ExprResult TheCallResult) {
6149   CallExpr *TheCall = (CallExpr *)TheCallResult.get();
6150   DeclRefExpr *DRE =
6151       cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts());
6152   FunctionDecl *FDecl = cast<FunctionDecl>(DRE->getDecl());
6153   unsigned BuiltinID = FDecl->getBuiltinID();
6154   assert((BuiltinID == Builtin::BI__builtin_nontemporal_store ||
6155           BuiltinID == Builtin::BI__builtin_nontemporal_load) &&
6156          "Unexpected nontemporal load/store builtin!");
6157   bool isStore = BuiltinID == Builtin::BI__builtin_nontemporal_store;
6158   unsigned numArgs = isStore ? 2 : 1;
6159 
6160   // Ensure that we have the proper number of arguments.
6161   if (checkArgCount(*this, TheCall, numArgs))
6162     return ExprError();
6163 
6164   // Inspect the last argument of the nontemporal builtin.  This should always
6165   // be a pointer type, from which we imply the type of the memory access.
6166   // Because it is a pointer type, we don't have to worry about any implicit
6167   // casts here.
6168   Expr *PointerArg = TheCall->getArg(numArgs - 1);
6169   ExprResult PointerArgResult =
6170       DefaultFunctionArrayLvalueConversion(PointerArg);
6171 
6172   if (PointerArgResult.isInvalid())
6173     return ExprError();
6174   PointerArg = PointerArgResult.get();
6175   TheCall->setArg(numArgs - 1, PointerArg);
6176 
6177   const PointerType *pointerType = PointerArg->getType()->getAs<PointerType>();
6178   if (!pointerType) {
6179     Diag(DRE->getBeginLoc(), diag::err_nontemporal_builtin_must_be_pointer)
6180         << PointerArg->getType() << PointerArg->getSourceRange();
6181     return ExprError();
6182   }
6183 
6184   QualType ValType = pointerType->getPointeeType();
6185 
6186   // Strip any qualifiers off ValType.
6187   ValType = ValType.getUnqualifiedType();
6188   if (!ValType->isIntegerType() && !ValType->isAnyPointerType() &&
6189       !ValType->isBlockPointerType() && !ValType->isFloatingType() &&
6190       !ValType->isVectorType()) {
6191     Diag(DRE->getBeginLoc(),
6192          diag::err_nontemporal_builtin_must_be_pointer_intfltptr_or_vector)
6193         << PointerArg->getType() << PointerArg->getSourceRange();
6194     return ExprError();
6195   }
6196 
6197   if (!isStore) {
6198     TheCall->setType(ValType);
6199     return TheCallResult;
6200   }
6201 
6202   ExprResult ValArg = TheCall->getArg(0);
6203   InitializedEntity Entity = InitializedEntity::InitializeParameter(
6204       Context, ValType, /*consume*/ false);
6205   ValArg = PerformCopyInitialization(Entity, SourceLocation(), ValArg);
6206   if (ValArg.isInvalid())
6207     return ExprError();
6208 
6209   TheCall->setArg(0, ValArg.get());
6210   TheCall->setType(Context.VoidTy);
6211   return TheCallResult;
6212 }
6213 
6214 /// CheckObjCString - Checks that the argument to the builtin
6215 /// CFString constructor is correct
6216 /// Note: It might also make sense to do the UTF-16 conversion here (would
6217 /// simplify the backend).
6218 bool Sema::CheckObjCString(Expr *Arg) {
6219   Arg = Arg->IgnoreParenCasts();
6220   StringLiteral *Literal = dyn_cast<StringLiteral>(Arg);
6221 
6222   if (!Literal || !Literal->isAscii()) {
6223     Diag(Arg->getBeginLoc(), diag::err_cfstring_literal_not_string_constant)
6224         << Arg->getSourceRange();
6225     return true;
6226   }
6227 
6228   if (Literal->containsNonAsciiOrNull()) {
6229     StringRef String = Literal->getString();
6230     unsigned NumBytes = String.size();
6231     SmallVector<llvm::UTF16, 128> ToBuf(NumBytes);
6232     const llvm::UTF8 *FromPtr = (const llvm::UTF8 *)String.data();
6233     llvm::UTF16 *ToPtr = &ToBuf[0];
6234 
6235     llvm::ConversionResult Result =
6236         llvm::ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, &ToPtr,
6237                                  ToPtr + NumBytes, llvm::strictConversion);
6238     // Check for conversion failure.
6239     if (Result != llvm::conversionOK)
6240       Diag(Arg->getBeginLoc(), diag::warn_cfstring_truncated)
6241           << Arg->getSourceRange();
6242   }
6243   return false;
6244 }
6245 
6246 /// CheckObjCString - Checks that the format string argument to the os_log()
6247 /// and os_trace() functions is correct, and converts it to const char *.
6248 ExprResult Sema::CheckOSLogFormatStringArg(Expr *Arg) {
6249   Arg = Arg->IgnoreParenCasts();
6250   auto *Literal = dyn_cast<StringLiteral>(Arg);
6251   if (!Literal) {
6252     if (auto *ObjcLiteral = dyn_cast<ObjCStringLiteral>(Arg)) {
6253       Literal = ObjcLiteral->getString();
6254     }
6255   }
6256 
6257   if (!Literal || (!Literal->isAscii() && !Literal->isUTF8())) {
6258     return ExprError(
6259         Diag(Arg->getBeginLoc(), diag::err_os_log_format_not_string_constant)
6260         << Arg->getSourceRange());
6261   }
6262 
6263   ExprResult Result(Literal);
6264   QualType ResultTy = Context.getPointerType(Context.CharTy.withConst());
6265   InitializedEntity Entity =
6266       InitializedEntity::InitializeParameter(Context, ResultTy, false);
6267   Result = PerformCopyInitialization(Entity, SourceLocation(), Result);
6268   return Result;
6269 }
6270 
6271 /// Check that the user is calling the appropriate va_start builtin for the
6272 /// target and calling convention.
6273 static bool checkVAStartABI(Sema &S, unsigned BuiltinID, Expr *Fn) {
6274   const llvm::Triple &TT = S.Context.getTargetInfo().getTriple();
6275   bool IsX64 = TT.getArch() == llvm::Triple::x86_64;
6276   bool IsAArch64 = (TT.getArch() == llvm::Triple::aarch64 ||
6277                     TT.getArch() == llvm::Triple::aarch64_32);
6278   bool IsWindows = TT.isOSWindows();
6279   bool IsMSVAStart = BuiltinID == Builtin::BI__builtin_ms_va_start;
6280   if (IsX64 || IsAArch64) {
6281     CallingConv CC = CC_C;
6282     if (const FunctionDecl *FD = S.getCurFunctionDecl())
6283       CC = FD->getType()->castAs<FunctionType>()->getCallConv();
6284     if (IsMSVAStart) {
6285       // Don't allow this in System V ABI functions.
6286       if (CC == CC_X86_64SysV || (!IsWindows && CC != CC_Win64))
6287         return S.Diag(Fn->getBeginLoc(),
6288                       diag::err_ms_va_start_used_in_sysv_function);
6289     } else {
6290       // On x86-64/AArch64 Unix, don't allow this in Win64 ABI functions.
6291       // On x64 Windows, don't allow this in System V ABI functions.
6292       // (Yes, that means there's no corresponding way to support variadic
6293       // System V ABI functions on Windows.)
6294       if ((IsWindows && CC == CC_X86_64SysV) ||
6295           (!IsWindows && CC == CC_Win64))
6296         return S.Diag(Fn->getBeginLoc(),
6297                       diag::err_va_start_used_in_wrong_abi_function)
6298                << !IsWindows;
6299     }
6300     return false;
6301   }
6302 
6303   if (IsMSVAStart)
6304     return S.Diag(Fn->getBeginLoc(), diag::err_builtin_x64_aarch64_only);
6305   return false;
6306 }
6307 
6308 static bool checkVAStartIsInVariadicFunction(Sema &S, Expr *Fn,
6309                                              ParmVarDecl **LastParam = nullptr) {
6310   // Determine whether the current function, block, or obj-c method is variadic
6311   // and get its parameter list.
6312   bool IsVariadic = false;
6313   ArrayRef<ParmVarDecl *> Params;
6314   DeclContext *Caller = S.CurContext;
6315   if (auto *Block = dyn_cast<BlockDecl>(Caller)) {
6316     IsVariadic = Block->isVariadic();
6317     Params = Block->parameters();
6318   } else if (auto *FD = dyn_cast<FunctionDecl>(Caller)) {
6319     IsVariadic = FD->isVariadic();
6320     Params = FD->parameters();
6321   } else if (auto *MD = dyn_cast<ObjCMethodDecl>(Caller)) {
6322     IsVariadic = MD->isVariadic();
6323     // FIXME: This isn't correct for methods (results in bogus warning).
6324     Params = MD->parameters();
6325   } else if (isa<CapturedDecl>(Caller)) {
6326     // We don't support va_start in a CapturedDecl.
6327     S.Diag(Fn->getBeginLoc(), diag::err_va_start_captured_stmt);
6328     return true;
6329   } else {
6330     // This must be some other declcontext that parses exprs.
6331     S.Diag(Fn->getBeginLoc(), diag::err_va_start_outside_function);
6332     return true;
6333   }
6334 
6335   if (!IsVariadic) {
6336     S.Diag(Fn->getBeginLoc(), diag::err_va_start_fixed_function);
6337     return true;
6338   }
6339 
6340   if (LastParam)
6341     *LastParam = Params.empty() ? nullptr : Params.back();
6342 
6343   return false;
6344 }
6345 
6346 /// Check the arguments to '__builtin_va_start' or '__builtin_ms_va_start'
6347 /// for validity.  Emit an error and return true on failure; return false
6348 /// on success.
6349 bool Sema::SemaBuiltinVAStart(unsigned BuiltinID, CallExpr *TheCall) {
6350   Expr *Fn = TheCall->getCallee();
6351 
6352   if (checkVAStartABI(*this, BuiltinID, Fn))
6353     return true;
6354 
6355   if (checkArgCount(*this, TheCall, 2))
6356     return true;
6357 
6358   // Type-check the first argument normally.
6359   if (checkBuiltinArgument(*this, TheCall, 0))
6360     return true;
6361 
6362   // Check that the current function is variadic, and get its last parameter.
6363   ParmVarDecl *LastParam;
6364   if (checkVAStartIsInVariadicFunction(*this, Fn, &LastParam))
6365     return true;
6366 
6367   // Verify that the second argument to the builtin is the last argument of the
6368   // current function or method.
6369   bool SecondArgIsLastNamedArgument = false;
6370   const Expr *Arg = TheCall->getArg(1)->IgnoreParenCasts();
6371 
6372   // These are valid if SecondArgIsLastNamedArgument is false after the next
6373   // block.
6374   QualType Type;
6375   SourceLocation ParamLoc;
6376   bool IsCRegister = false;
6377 
6378   if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Arg)) {
6379     if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(DR->getDecl())) {
6380       SecondArgIsLastNamedArgument = PV == LastParam;
6381 
6382       Type = PV->getType();
6383       ParamLoc = PV->getLocation();
6384       IsCRegister =
6385           PV->getStorageClass() == SC_Register && !getLangOpts().CPlusPlus;
6386     }
6387   }
6388 
6389   if (!SecondArgIsLastNamedArgument)
6390     Diag(TheCall->getArg(1)->getBeginLoc(),
6391          diag::warn_second_arg_of_va_start_not_last_named_param);
6392   else if (IsCRegister || Type->isReferenceType() ||
6393            Type->isSpecificBuiltinType(BuiltinType::Float) || [=] {
6394              // Promotable integers are UB, but enumerations need a bit of
6395              // extra checking to see what their promotable type actually is.
6396              if (!Type->isPromotableIntegerType())
6397                return false;
6398              if (!Type->isEnumeralType())
6399                return true;
6400              const EnumDecl *ED = Type->castAs<EnumType>()->getDecl();
6401              return !(ED &&
6402                       Context.typesAreCompatible(ED->getPromotionType(), Type));
6403            }()) {
6404     unsigned Reason = 0;
6405     if (Type->isReferenceType())  Reason = 1;
6406     else if (IsCRegister)         Reason = 2;
6407     Diag(Arg->getBeginLoc(), diag::warn_va_start_type_is_undefined) << Reason;
6408     Diag(ParamLoc, diag::note_parameter_type) << Type;
6409   }
6410 
6411   TheCall->setType(Context.VoidTy);
6412   return false;
6413 }
6414 
6415 bool Sema::SemaBuiltinVAStartARMMicrosoft(CallExpr *Call) {
6416   // void __va_start(va_list *ap, const char *named_addr, size_t slot_size,
6417   //                 const char *named_addr);
6418 
6419   Expr *Func = Call->getCallee();
6420 
6421   if (Call->getNumArgs() < 3)
6422     return Diag(Call->getEndLoc(),
6423                 diag::err_typecheck_call_too_few_args_at_least)
6424            << 0 /*function call*/ << 3 << Call->getNumArgs();
6425 
6426   // Type-check the first argument normally.
6427   if (checkBuiltinArgument(*this, Call, 0))
6428     return true;
6429 
6430   // Check that the current function is variadic.
6431   if (checkVAStartIsInVariadicFunction(*this, Func))
6432     return true;
6433 
6434   // __va_start on Windows does not validate the parameter qualifiers
6435 
6436   const Expr *Arg1 = Call->getArg(1)->IgnoreParens();
6437   const Type *Arg1Ty = Arg1->getType().getCanonicalType().getTypePtr();
6438 
6439   const Expr *Arg2 = Call->getArg(2)->IgnoreParens();
6440   const Type *Arg2Ty = Arg2->getType().getCanonicalType().getTypePtr();
6441 
6442   const QualType &ConstCharPtrTy =
6443       Context.getPointerType(Context.CharTy.withConst());
6444   if (!Arg1Ty->isPointerType() ||
6445       Arg1Ty->getPointeeType().withoutLocalFastQualifiers() != Context.CharTy)
6446     Diag(Arg1->getBeginLoc(), diag::err_typecheck_convert_incompatible)
6447         << Arg1->getType() << ConstCharPtrTy << 1 /* different class */
6448         << 0                                      /* qualifier difference */
6449         << 3                                      /* parameter mismatch */
6450         << 2 << Arg1->getType() << ConstCharPtrTy;
6451 
6452   const QualType SizeTy = Context.getSizeType();
6453   if (Arg2Ty->getCanonicalTypeInternal().withoutLocalFastQualifiers() != SizeTy)
6454     Diag(Arg2->getBeginLoc(), diag::err_typecheck_convert_incompatible)
6455         << Arg2->getType() << SizeTy << 1 /* different class */
6456         << 0                              /* qualifier difference */
6457         << 3                              /* parameter mismatch */
6458         << 3 << Arg2->getType() << SizeTy;
6459 
6460   return false;
6461 }
6462 
6463 /// SemaBuiltinUnorderedCompare - Handle functions like __builtin_isgreater and
6464 /// friends.  This is declared to take (...), so we have to check everything.
6465 bool Sema::SemaBuiltinUnorderedCompare(CallExpr *TheCall) {
6466   if (checkArgCount(*this, TheCall, 2))
6467     return true;
6468 
6469   ExprResult OrigArg0 = TheCall->getArg(0);
6470   ExprResult OrigArg1 = TheCall->getArg(1);
6471 
6472   // Do standard promotions between the two arguments, returning their common
6473   // type.
6474   QualType Res = UsualArithmeticConversions(
6475       OrigArg0, OrigArg1, TheCall->getExprLoc(), ACK_Comparison);
6476   if (OrigArg0.isInvalid() || OrigArg1.isInvalid())
6477     return true;
6478 
6479   // Make sure any conversions are pushed back into the call; this is
6480   // type safe since unordered compare builtins are declared as "_Bool
6481   // foo(...)".
6482   TheCall->setArg(0, OrigArg0.get());
6483   TheCall->setArg(1, OrigArg1.get());
6484 
6485   if (OrigArg0.get()->isTypeDependent() || OrigArg1.get()->isTypeDependent())
6486     return false;
6487 
6488   // If the common type isn't a real floating type, then the arguments were
6489   // invalid for this operation.
6490   if (Res.isNull() || !Res->isRealFloatingType())
6491     return Diag(OrigArg0.get()->getBeginLoc(),
6492                 diag::err_typecheck_call_invalid_ordered_compare)
6493            << OrigArg0.get()->getType() << OrigArg1.get()->getType()
6494            << SourceRange(OrigArg0.get()->getBeginLoc(),
6495                           OrigArg1.get()->getEndLoc());
6496 
6497   return false;
6498 }
6499 
6500 /// SemaBuiltinSemaBuiltinFPClassification - Handle functions like
6501 /// __builtin_isnan and friends.  This is declared to take (...), so we have
6502 /// to check everything. We expect the last argument to be a floating point
6503 /// value.
6504 bool Sema::SemaBuiltinFPClassification(CallExpr *TheCall, unsigned NumArgs) {
6505   if (checkArgCount(*this, TheCall, NumArgs))
6506     return true;
6507 
6508   // __builtin_fpclassify is the only case where NumArgs != 1, so we can count
6509   // on all preceding parameters just being int.  Try all of those.
6510   for (unsigned i = 0; i < NumArgs - 1; ++i) {
6511     Expr *Arg = TheCall->getArg(i);
6512 
6513     if (Arg->isTypeDependent())
6514       return false;
6515 
6516     ExprResult Res = PerformImplicitConversion(Arg, Context.IntTy, AA_Passing);
6517 
6518     if (Res.isInvalid())
6519       return true;
6520     TheCall->setArg(i, Res.get());
6521   }
6522 
6523   Expr *OrigArg = TheCall->getArg(NumArgs-1);
6524 
6525   if (OrigArg->isTypeDependent())
6526     return false;
6527 
6528   // Usual Unary Conversions will convert half to float, which we want for
6529   // machines that use fp16 conversion intrinsics. Else, we wnat to leave the
6530   // type how it is, but do normal L->Rvalue conversions.
6531   if (Context.getTargetInfo().useFP16ConversionIntrinsics())
6532     OrigArg = UsualUnaryConversions(OrigArg).get();
6533   else
6534     OrigArg = DefaultFunctionArrayLvalueConversion(OrigArg).get();
6535   TheCall->setArg(NumArgs - 1, OrigArg);
6536 
6537   // This operation requires a non-_Complex floating-point number.
6538   if (!OrigArg->getType()->isRealFloatingType())
6539     return Diag(OrigArg->getBeginLoc(),
6540                 diag::err_typecheck_call_invalid_unary_fp)
6541            << OrigArg->getType() << OrigArg->getSourceRange();
6542 
6543   return false;
6544 }
6545 
6546 /// Perform semantic analysis for a call to __builtin_complex.
6547 bool Sema::SemaBuiltinComplex(CallExpr *TheCall) {
6548   if (checkArgCount(*this, TheCall, 2))
6549     return true;
6550 
6551   bool Dependent = false;
6552   for (unsigned I = 0; I != 2; ++I) {
6553     Expr *Arg = TheCall->getArg(I);
6554     QualType T = Arg->getType();
6555     if (T->isDependentType()) {
6556       Dependent = true;
6557       continue;
6558     }
6559 
6560     // Despite supporting _Complex int, GCC requires a real floating point type
6561     // for the operands of __builtin_complex.
6562     if (!T->isRealFloatingType()) {
6563       return Diag(Arg->getBeginLoc(), diag::err_typecheck_call_requires_real_fp)
6564              << Arg->getType() << Arg->getSourceRange();
6565     }
6566 
6567     ExprResult Converted = DefaultLvalueConversion(Arg);
6568     if (Converted.isInvalid())
6569       return true;
6570     TheCall->setArg(I, Converted.get());
6571   }
6572 
6573   if (Dependent) {
6574     TheCall->setType(Context.DependentTy);
6575     return false;
6576   }
6577 
6578   Expr *Real = TheCall->getArg(0);
6579   Expr *Imag = TheCall->getArg(1);
6580   if (!Context.hasSameType(Real->getType(), Imag->getType())) {
6581     return Diag(Real->getBeginLoc(),
6582                 diag::err_typecheck_call_different_arg_types)
6583            << Real->getType() << Imag->getType()
6584            << Real->getSourceRange() << Imag->getSourceRange();
6585   }
6586 
6587   // We don't allow _Complex _Float16 nor _Complex __fp16 as type specifiers;
6588   // don't allow this builtin to form those types either.
6589   // FIXME: Should we allow these types?
6590   if (Real->getType()->isFloat16Type())
6591     return Diag(TheCall->getBeginLoc(), diag::err_invalid_complex_spec)
6592            << "_Float16";
6593   if (Real->getType()->isHalfType())
6594     return Diag(TheCall->getBeginLoc(), diag::err_invalid_complex_spec)
6595            << "half";
6596 
6597   TheCall->setType(Context.getComplexType(Real->getType()));
6598   return false;
6599 }
6600 
6601 // Customized Sema Checking for VSX builtins that have the following signature:
6602 // vector [...] builtinName(vector [...], vector [...], const int);
6603 // Which takes the same type of vectors (any legal vector type) for the first
6604 // two arguments and takes compile time constant for the third argument.
6605 // Example builtins are :
6606 // vector double vec_xxpermdi(vector double, vector double, int);
6607 // vector short vec_xxsldwi(vector short, vector short, int);
6608 bool Sema::SemaBuiltinVSX(CallExpr *TheCall) {
6609   unsigned ExpectedNumArgs = 3;
6610   if (checkArgCount(*this, TheCall, ExpectedNumArgs))
6611     return true;
6612 
6613   // Check the third argument is a compile time constant
6614   if (!TheCall->getArg(2)->isIntegerConstantExpr(Context))
6615     return Diag(TheCall->getBeginLoc(),
6616                 diag::err_vsx_builtin_nonconstant_argument)
6617            << 3 /* argument index */ << TheCall->getDirectCallee()
6618            << SourceRange(TheCall->getArg(2)->getBeginLoc(),
6619                           TheCall->getArg(2)->getEndLoc());
6620 
6621   QualType Arg1Ty = TheCall->getArg(0)->getType();
6622   QualType Arg2Ty = TheCall->getArg(1)->getType();
6623 
6624   // Check the type of argument 1 and argument 2 are vectors.
6625   SourceLocation BuiltinLoc = TheCall->getBeginLoc();
6626   if ((!Arg1Ty->isVectorType() && !Arg1Ty->isDependentType()) ||
6627       (!Arg2Ty->isVectorType() && !Arg2Ty->isDependentType())) {
6628     return Diag(BuiltinLoc, diag::err_vec_builtin_non_vector)
6629            << TheCall->getDirectCallee()
6630            << SourceRange(TheCall->getArg(0)->getBeginLoc(),
6631                           TheCall->getArg(1)->getEndLoc());
6632   }
6633 
6634   // Check the first two arguments are the same type.
6635   if (!Context.hasSameUnqualifiedType(Arg1Ty, Arg2Ty)) {
6636     return Diag(BuiltinLoc, diag::err_vec_builtin_incompatible_vector)
6637            << TheCall->getDirectCallee()
6638            << SourceRange(TheCall->getArg(0)->getBeginLoc(),
6639                           TheCall->getArg(1)->getEndLoc());
6640   }
6641 
6642   // When default clang type checking is turned off and the customized type
6643   // checking is used, the returning type of the function must be explicitly
6644   // set. Otherwise it is _Bool by default.
6645   TheCall->setType(Arg1Ty);
6646 
6647   return false;
6648 }
6649 
6650 /// SemaBuiltinShuffleVector - Handle __builtin_shufflevector.
6651 // This is declared to take (...), so we have to check everything.
6652 ExprResult Sema::SemaBuiltinShuffleVector(CallExpr *TheCall) {
6653   if (TheCall->getNumArgs() < 2)
6654     return ExprError(Diag(TheCall->getEndLoc(),
6655                           diag::err_typecheck_call_too_few_args_at_least)
6656                      << 0 /*function call*/ << 2 << TheCall->getNumArgs()
6657                      << TheCall->getSourceRange());
6658 
6659   // Determine which of the following types of shufflevector we're checking:
6660   // 1) unary, vector mask: (lhs, mask)
6661   // 2) binary, scalar mask: (lhs, rhs, index, ..., index)
6662   QualType resType = TheCall->getArg(0)->getType();
6663   unsigned numElements = 0;
6664 
6665   if (!TheCall->getArg(0)->isTypeDependent() &&
6666       !TheCall->getArg(1)->isTypeDependent()) {
6667     QualType LHSType = TheCall->getArg(0)->getType();
6668     QualType RHSType = TheCall->getArg(1)->getType();
6669 
6670     if (!LHSType->isVectorType() || !RHSType->isVectorType())
6671       return ExprError(
6672           Diag(TheCall->getBeginLoc(), diag::err_vec_builtin_non_vector)
6673           << TheCall->getDirectCallee()
6674           << SourceRange(TheCall->getArg(0)->getBeginLoc(),
6675                          TheCall->getArg(1)->getEndLoc()));
6676 
6677     numElements = LHSType->castAs<VectorType>()->getNumElements();
6678     unsigned numResElements = TheCall->getNumArgs() - 2;
6679 
6680     // Check to see if we have a call with 2 vector arguments, the unary shuffle
6681     // with mask.  If so, verify that RHS is an integer vector type with the
6682     // same number of elts as lhs.
6683     if (TheCall->getNumArgs() == 2) {
6684       if (!RHSType->hasIntegerRepresentation() ||
6685           RHSType->castAs<VectorType>()->getNumElements() != numElements)
6686         return ExprError(Diag(TheCall->getBeginLoc(),
6687                               diag::err_vec_builtin_incompatible_vector)
6688                          << TheCall->getDirectCallee()
6689                          << SourceRange(TheCall->getArg(1)->getBeginLoc(),
6690                                         TheCall->getArg(1)->getEndLoc()));
6691     } else if (!Context.hasSameUnqualifiedType(LHSType, RHSType)) {
6692       return ExprError(Diag(TheCall->getBeginLoc(),
6693                             diag::err_vec_builtin_incompatible_vector)
6694                        << TheCall->getDirectCallee()
6695                        << SourceRange(TheCall->getArg(0)->getBeginLoc(),
6696                                       TheCall->getArg(1)->getEndLoc()));
6697     } else if (numElements != numResElements) {
6698       QualType eltType = LHSType->castAs<VectorType>()->getElementType();
6699       resType = Context.getVectorType(eltType, numResElements,
6700                                       VectorType::GenericVector);
6701     }
6702   }
6703 
6704   for (unsigned i = 2; i < TheCall->getNumArgs(); i++) {
6705     if (TheCall->getArg(i)->isTypeDependent() ||
6706         TheCall->getArg(i)->isValueDependent())
6707       continue;
6708 
6709     Optional<llvm::APSInt> Result;
6710     if (!(Result = TheCall->getArg(i)->getIntegerConstantExpr(Context)))
6711       return ExprError(Diag(TheCall->getBeginLoc(),
6712                             diag::err_shufflevector_nonconstant_argument)
6713                        << TheCall->getArg(i)->getSourceRange());
6714 
6715     // Allow -1 which will be translated to undef in the IR.
6716     if (Result->isSigned() && Result->isAllOnesValue())
6717       continue;
6718 
6719     if (Result->getActiveBits() > 64 ||
6720         Result->getZExtValue() >= numElements * 2)
6721       return ExprError(Diag(TheCall->getBeginLoc(),
6722                             diag::err_shufflevector_argument_too_large)
6723                        << TheCall->getArg(i)->getSourceRange());
6724   }
6725 
6726   SmallVector<Expr*, 32> exprs;
6727 
6728   for (unsigned i = 0, e = TheCall->getNumArgs(); i != e; i++) {
6729     exprs.push_back(TheCall->getArg(i));
6730     TheCall->setArg(i, nullptr);
6731   }
6732 
6733   return new (Context) ShuffleVectorExpr(Context, exprs, resType,
6734                                          TheCall->getCallee()->getBeginLoc(),
6735                                          TheCall->getRParenLoc());
6736 }
6737 
6738 /// SemaConvertVectorExpr - Handle __builtin_convertvector
6739 ExprResult Sema::SemaConvertVectorExpr(Expr *E, TypeSourceInfo *TInfo,
6740                                        SourceLocation BuiltinLoc,
6741                                        SourceLocation RParenLoc) {
6742   ExprValueKind VK = VK_PRValue;
6743   ExprObjectKind OK = OK_Ordinary;
6744   QualType DstTy = TInfo->getType();
6745   QualType SrcTy = E->getType();
6746 
6747   if (!SrcTy->isVectorType() && !SrcTy->isDependentType())
6748     return ExprError(Diag(BuiltinLoc,
6749                           diag::err_convertvector_non_vector)
6750                      << E->getSourceRange());
6751   if (!DstTy->isVectorType() && !DstTy->isDependentType())
6752     return ExprError(Diag(BuiltinLoc,
6753                           diag::err_convertvector_non_vector_type));
6754 
6755   if (!SrcTy->isDependentType() && !DstTy->isDependentType()) {
6756     unsigned SrcElts = SrcTy->castAs<VectorType>()->getNumElements();
6757     unsigned DstElts = DstTy->castAs<VectorType>()->getNumElements();
6758     if (SrcElts != DstElts)
6759       return ExprError(Diag(BuiltinLoc,
6760                             diag::err_convertvector_incompatible_vector)
6761                        << E->getSourceRange());
6762   }
6763 
6764   return new (Context)
6765       ConvertVectorExpr(E, TInfo, DstTy, VK, OK, BuiltinLoc, RParenLoc);
6766 }
6767 
6768 /// SemaBuiltinPrefetch - Handle __builtin_prefetch.
6769 // This is declared to take (const void*, ...) and can take two
6770 // optional constant int args.
6771 bool Sema::SemaBuiltinPrefetch(CallExpr *TheCall) {
6772   unsigned NumArgs = TheCall->getNumArgs();
6773 
6774   if (NumArgs > 3)
6775     return Diag(TheCall->getEndLoc(),
6776                 diag::err_typecheck_call_too_many_args_at_most)
6777            << 0 /*function call*/ << 3 << NumArgs << TheCall->getSourceRange();
6778 
6779   // Argument 0 is checked for us and the remaining arguments must be
6780   // constant integers.
6781   for (unsigned i = 1; i != NumArgs; ++i)
6782     if (SemaBuiltinConstantArgRange(TheCall, i, 0, i == 1 ? 1 : 3))
6783       return true;
6784 
6785   return false;
6786 }
6787 
6788 /// SemaBuiltinArithmeticFence - Handle __arithmetic_fence.
6789 bool Sema::SemaBuiltinArithmeticFence(CallExpr *TheCall) {
6790   if (!Context.getTargetInfo().checkArithmeticFenceSupported())
6791     return Diag(TheCall->getBeginLoc(), diag::err_builtin_target_unsupported)
6792            << SourceRange(TheCall->getBeginLoc(), TheCall->getEndLoc());
6793   if (checkArgCount(*this, TheCall, 1))
6794     return true;
6795   Expr *Arg = TheCall->getArg(0);
6796   if (Arg->isInstantiationDependent())
6797     return false;
6798 
6799   QualType ArgTy = Arg->getType();
6800   if (!ArgTy->hasFloatingRepresentation())
6801     return Diag(TheCall->getEndLoc(), diag::err_typecheck_expect_flt_or_vector)
6802            << ArgTy;
6803   if (Arg->isLValue()) {
6804     ExprResult FirstArg = DefaultLvalueConversion(Arg);
6805     TheCall->setArg(0, FirstArg.get());
6806   }
6807   TheCall->setType(TheCall->getArg(0)->getType());
6808   return false;
6809 }
6810 
6811 /// SemaBuiltinAssume - Handle __assume (MS Extension).
6812 // __assume does not evaluate its arguments, and should warn if its argument
6813 // has side effects.
6814 bool Sema::SemaBuiltinAssume(CallExpr *TheCall) {
6815   Expr *Arg = TheCall->getArg(0);
6816   if (Arg->isInstantiationDependent()) return false;
6817 
6818   if (Arg->HasSideEffects(Context))
6819     Diag(Arg->getBeginLoc(), diag::warn_assume_side_effects)
6820         << Arg->getSourceRange()
6821         << cast<FunctionDecl>(TheCall->getCalleeDecl())->getIdentifier();
6822 
6823   return false;
6824 }
6825 
6826 /// Handle __builtin_alloca_with_align. This is declared
6827 /// as (size_t, size_t) where the second size_t must be a power of 2 greater
6828 /// than 8.
6829 bool Sema::SemaBuiltinAllocaWithAlign(CallExpr *TheCall) {
6830   // The alignment must be a constant integer.
6831   Expr *Arg = TheCall->getArg(1);
6832 
6833   // We can't check the value of a dependent argument.
6834   if (!Arg->isTypeDependent() && !Arg->isValueDependent()) {
6835     if (const auto *UE =
6836             dyn_cast<UnaryExprOrTypeTraitExpr>(Arg->IgnoreParenImpCasts()))
6837       if (UE->getKind() == UETT_AlignOf ||
6838           UE->getKind() == UETT_PreferredAlignOf)
6839         Diag(TheCall->getBeginLoc(), diag::warn_alloca_align_alignof)
6840             << Arg->getSourceRange();
6841 
6842     llvm::APSInt Result = Arg->EvaluateKnownConstInt(Context);
6843 
6844     if (!Result.isPowerOf2())
6845       return Diag(TheCall->getBeginLoc(), diag::err_alignment_not_power_of_two)
6846              << Arg->getSourceRange();
6847 
6848     if (Result < Context.getCharWidth())
6849       return Diag(TheCall->getBeginLoc(), diag::err_alignment_too_small)
6850              << (unsigned)Context.getCharWidth() << Arg->getSourceRange();
6851 
6852     if (Result > std::numeric_limits<int32_t>::max())
6853       return Diag(TheCall->getBeginLoc(), diag::err_alignment_too_big)
6854              << std::numeric_limits<int32_t>::max() << Arg->getSourceRange();
6855   }
6856 
6857   return false;
6858 }
6859 
6860 /// Handle __builtin_assume_aligned. This is declared
6861 /// as (const void*, size_t, ...) and can take one optional constant int arg.
6862 bool Sema::SemaBuiltinAssumeAligned(CallExpr *TheCall) {
6863   unsigned NumArgs = TheCall->getNumArgs();
6864 
6865   if (NumArgs > 3)
6866     return Diag(TheCall->getEndLoc(),
6867                 diag::err_typecheck_call_too_many_args_at_most)
6868            << 0 /*function call*/ << 3 << NumArgs << TheCall->getSourceRange();
6869 
6870   // The alignment must be a constant integer.
6871   Expr *Arg = TheCall->getArg(1);
6872 
6873   // We can't check the value of a dependent argument.
6874   if (!Arg->isTypeDependent() && !Arg->isValueDependent()) {
6875     llvm::APSInt Result;
6876     if (SemaBuiltinConstantArg(TheCall, 1, Result))
6877       return true;
6878 
6879     if (!Result.isPowerOf2())
6880       return Diag(TheCall->getBeginLoc(), diag::err_alignment_not_power_of_two)
6881              << Arg->getSourceRange();
6882 
6883     if (Result > Sema::MaximumAlignment)
6884       Diag(TheCall->getBeginLoc(), diag::warn_assume_aligned_too_great)
6885           << Arg->getSourceRange() << Sema::MaximumAlignment;
6886   }
6887 
6888   if (NumArgs > 2) {
6889     ExprResult Arg(TheCall->getArg(2));
6890     InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
6891       Context.getSizeType(), false);
6892     Arg = PerformCopyInitialization(Entity, SourceLocation(), Arg);
6893     if (Arg.isInvalid()) return true;
6894     TheCall->setArg(2, Arg.get());
6895   }
6896 
6897   return false;
6898 }
6899 
6900 bool Sema::SemaBuiltinOSLogFormat(CallExpr *TheCall) {
6901   unsigned BuiltinID =
6902       cast<FunctionDecl>(TheCall->getCalleeDecl())->getBuiltinID();
6903   bool IsSizeCall = BuiltinID == Builtin::BI__builtin_os_log_format_buffer_size;
6904 
6905   unsigned NumArgs = TheCall->getNumArgs();
6906   unsigned NumRequiredArgs = IsSizeCall ? 1 : 2;
6907   if (NumArgs < NumRequiredArgs) {
6908     return Diag(TheCall->getEndLoc(), diag::err_typecheck_call_too_few_args)
6909            << 0 /* function call */ << NumRequiredArgs << NumArgs
6910            << TheCall->getSourceRange();
6911   }
6912   if (NumArgs >= NumRequiredArgs + 0x100) {
6913     return Diag(TheCall->getEndLoc(),
6914                 diag::err_typecheck_call_too_many_args_at_most)
6915            << 0 /* function call */ << (NumRequiredArgs + 0xff) << NumArgs
6916            << TheCall->getSourceRange();
6917   }
6918   unsigned i = 0;
6919 
6920   // For formatting call, check buffer arg.
6921   if (!IsSizeCall) {
6922     ExprResult Arg(TheCall->getArg(i));
6923     InitializedEntity Entity = InitializedEntity::InitializeParameter(
6924         Context, Context.VoidPtrTy, false);
6925     Arg = PerformCopyInitialization(Entity, SourceLocation(), Arg);
6926     if (Arg.isInvalid())
6927       return true;
6928     TheCall->setArg(i, Arg.get());
6929     i++;
6930   }
6931 
6932   // Check string literal arg.
6933   unsigned FormatIdx = i;
6934   {
6935     ExprResult Arg = CheckOSLogFormatStringArg(TheCall->getArg(i));
6936     if (Arg.isInvalid())
6937       return true;
6938     TheCall->setArg(i, Arg.get());
6939     i++;
6940   }
6941 
6942   // Make sure variadic args are scalar.
6943   unsigned FirstDataArg = i;
6944   while (i < NumArgs) {
6945     ExprResult Arg = DefaultVariadicArgumentPromotion(
6946         TheCall->getArg(i), VariadicFunction, nullptr);
6947     if (Arg.isInvalid())
6948       return true;
6949     CharUnits ArgSize = Context.getTypeSizeInChars(Arg.get()->getType());
6950     if (ArgSize.getQuantity() >= 0x100) {
6951       return Diag(Arg.get()->getEndLoc(), diag::err_os_log_argument_too_big)
6952              << i << (int)ArgSize.getQuantity() << 0xff
6953              << TheCall->getSourceRange();
6954     }
6955     TheCall->setArg(i, Arg.get());
6956     i++;
6957   }
6958 
6959   // Check formatting specifiers. NOTE: We're only doing this for the non-size
6960   // call to avoid duplicate diagnostics.
6961   if (!IsSizeCall) {
6962     llvm::SmallBitVector CheckedVarArgs(NumArgs, false);
6963     ArrayRef<const Expr *> Args(TheCall->getArgs(), TheCall->getNumArgs());
6964     bool Success = CheckFormatArguments(
6965         Args, /*HasVAListArg*/ false, FormatIdx, FirstDataArg, FST_OSLog,
6966         VariadicFunction, TheCall->getBeginLoc(), SourceRange(),
6967         CheckedVarArgs);
6968     if (!Success)
6969       return true;
6970   }
6971 
6972   if (IsSizeCall) {
6973     TheCall->setType(Context.getSizeType());
6974   } else {
6975     TheCall->setType(Context.VoidPtrTy);
6976   }
6977   return false;
6978 }
6979 
6980 /// SemaBuiltinConstantArg - Handle a check if argument ArgNum of CallExpr
6981 /// TheCall is a constant expression.
6982 bool Sema::SemaBuiltinConstantArg(CallExpr *TheCall, int ArgNum,
6983                                   llvm::APSInt &Result) {
6984   Expr *Arg = TheCall->getArg(ArgNum);
6985   DeclRefExpr *DRE =cast<DeclRefExpr>(TheCall->getCallee()->IgnoreParenCasts());
6986   FunctionDecl *FDecl = cast<FunctionDecl>(DRE->getDecl());
6987 
6988   if (Arg->isTypeDependent() || Arg->isValueDependent()) return false;
6989 
6990   Optional<llvm::APSInt> R;
6991   if (!(R = Arg->getIntegerConstantExpr(Context)))
6992     return Diag(TheCall->getBeginLoc(), diag::err_constant_integer_arg_type)
6993            << FDecl->getDeclName() << Arg->getSourceRange();
6994   Result = *R;
6995   return false;
6996 }
6997 
6998 /// SemaBuiltinConstantArgRange - Handle a check if argument ArgNum of CallExpr
6999 /// TheCall is a constant expression in the range [Low, High].
7000 bool Sema::SemaBuiltinConstantArgRange(CallExpr *TheCall, int ArgNum,
7001                                        int Low, int High, bool RangeIsError) {
7002   if (isConstantEvaluated())
7003     return false;
7004   llvm::APSInt Result;
7005 
7006   // We can't check the value of a dependent argument.
7007   Expr *Arg = TheCall->getArg(ArgNum);
7008   if (Arg->isTypeDependent() || Arg->isValueDependent())
7009     return false;
7010 
7011   // Check constant-ness first.
7012   if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
7013     return true;
7014 
7015   if (Result.getSExtValue() < Low || Result.getSExtValue() > High) {
7016     if (RangeIsError)
7017       return Diag(TheCall->getBeginLoc(), diag::err_argument_invalid_range)
7018              << toString(Result, 10) << Low << High << Arg->getSourceRange();
7019     else
7020       // Defer the warning until we know if the code will be emitted so that
7021       // dead code can ignore this.
7022       DiagRuntimeBehavior(TheCall->getBeginLoc(), TheCall,
7023                           PDiag(diag::warn_argument_invalid_range)
7024                               << toString(Result, 10) << Low << High
7025                               << Arg->getSourceRange());
7026   }
7027 
7028   return false;
7029 }
7030 
7031 /// SemaBuiltinConstantArgMultiple - Handle a check if argument ArgNum of CallExpr
7032 /// TheCall is a constant expression is a multiple of Num..
7033 bool Sema::SemaBuiltinConstantArgMultiple(CallExpr *TheCall, int ArgNum,
7034                                           unsigned Num) {
7035   llvm::APSInt Result;
7036 
7037   // We can't check the value of a dependent argument.
7038   Expr *Arg = TheCall->getArg(ArgNum);
7039   if (Arg->isTypeDependent() || Arg->isValueDependent())
7040     return false;
7041 
7042   // Check constant-ness first.
7043   if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
7044     return true;
7045 
7046   if (Result.getSExtValue() % Num != 0)
7047     return Diag(TheCall->getBeginLoc(), diag::err_argument_not_multiple)
7048            << Num << Arg->getSourceRange();
7049 
7050   return false;
7051 }
7052 
7053 /// SemaBuiltinConstantArgPower2 - Check if argument ArgNum of TheCall is a
7054 /// constant expression representing a power of 2.
7055 bool Sema::SemaBuiltinConstantArgPower2(CallExpr *TheCall, int ArgNum) {
7056   llvm::APSInt Result;
7057 
7058   // We can't check the value of a dependent argument.
7059   Expr *Arg = TheCall->getArg(ArgNum);
7060   if (Arg->isTypeDependent() || Arg->isValueDependent())
7061     return false;
7062 
7063   // Check constant-ness first.
7064   if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
7065     return true;
7066 
7067   // Bit-twiddling to test for a power of 2: for x > 0, x & (x-1) is zero if
7068   // and only if x is a power of 2.
7069   if (Result.isStrictlyPositive() && (Result & (Result - 1)) == 0)
7070     return false;
7071 
7072   return Diag(TheCall->getBeginLoc(), diag::err_argument_not_power_of_2)
7073          << Arg->getSourceRange();
7074 }
7075 
7076 static bool IsShiftedByte(llvm::APSInt Value) {
7077   if (Value.isNegative())
7078     return false;
7079 
7080   // Check if it's a shifted byte, by shifting it down
7081   while (true) {
7082     // If the value fits in the bottom byte, the check passes.
7083     if (Value < 0x100)
7084       return true;
7085 
7086     // Otherwise, if the value has _any_ bits in the bottom byte, the check
7087     // fails.
7088     if ((Value & 0xFF) != 0)
7089       return false;
7090 
7091     // If the bottom 8 bits are all 0, but something above that is nonzero,
7092     // then shifting the value right by 8 bits won't affect whether it's a
7093     // shifted byte or not. So do that, and go round again.
7094     Value >>= 8;
7095   }
7096 }
7097 
7098 /// SemaBuiltinConstantArgShiftedByte - Check if argument ArgNum of TheCall is
7099 /// a constant expression representing an arbitrary byte value shifted left by
7100 /// a multiple of 8 bits.
7101 bool Sema::SemaBuiltinConstantArgShiftedByte(CallExpr *TheCall, int ArgNum,
7102                                              unsigned ArgBits) {
7103   llvm::APSInt Result;
7104 
7105   // We can't check the value of a dependent argument.
7106   Expr *Arg = TheCall->getArg(ArgNum);
7107   if (Arg->isTypeDependent() || Arg->isValueDependent())
7108     return false;
7109 
7110   // Check constant-ness first.
7111   if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
7112     return true;
7113 
7114   // Truncate to the given size.
7115   Result = Result.getLoBits(ArgBits);
7116   Result.setIsUnsigned(true);
7117 
7118   if (IsShiftedByte(Result))
7119     return false;
7120 
7121   return Diag(TheCall->getBeginLoc(), diag::err_argument_not_shifted_byte)
7122          << Arg->getSourceRange();
7123 }
7124 
7125 /// SemaBuiltinConstantArgShiftedByteOr0xFF - Check if argument ArgNum of
7126 /// TheCall is a constant expression representing either a shifted byte value,
7127 /// or a value of the form 0x??FF (i.e. a member of the arithmetic progression
7128 /// 0x00FF, 0x01FF, ..., 0xFFFF). This strange range check is needed for some
7129 /// Arm MVE intrinsics.
7130 bool Sema::SemaBuiltinConstantArgShiftedByteOrXXFF(CallExpr *TheCall,
7131                                                    int ArgNum,
7132                                                    unsigned ArgBits) {
7133   llvm::APSInt Result;
7134 
7135   // We can't check the value of a dependent argument.
7136   Expr *Arg = TheCall->getArg(ArgNum);
7137   if (Arg->isTypeDependent() || Arg->isValueDependent())
7138     return false;
7139 
7140   // Check constant-ness first.
7141   if (SemaBuiltinConstantArg(TheCall, ArgNum, Result))
7142     return true;
7143 
7144   // Truncate to the given size.
7145   Result = Result.getLoBits(ArgBits);
7146   Result.setIsUnsigned(true);
7147 
7148   // Check to see if it's in either of the required forms.
7149   if (IsShiftedByte(Result) ||
7150       (Result > 0 && Result < 0x10000 && (Result & 0xFF) == 0xFF))
7151     return false;
7152 
7153   return Diag(TheCall->getBeginLoc(),
7154               diag::err_argument_not_shifted_byte_or_xxff)
7155          << Arg->getSourceRange();
7156 }
7157 
7158 /// SemaBuiltinARMMemoryTaggingCall - Handle calls of memory tagging extensions
7159 bool Sema::SemaBuiltinARMMemoryTaggingCall(unsigned BuiltinID, CallExpr *TheCall) {
7160   if (BuiltinID == AArch64::BI__builtin_arm_irg) {
7161     if (checkArgCount(*this, TheCall, 2))
7162       return true;
7163     Expr *Arg0 = TheCall->getArg(0);
7164     Expr *Arg1 = TheCall->getArg(1);
7165 
7166     ExprResult FirstArg = DefaultFunctionArrayLvalueConversion(Arg0);
7167     if (FirstArg.isInvalid())
7168       return true;
7169     QualType FirstArgType = FirstArg.get()->getType();
7170     if (!FirstArgType->isAnyPointerType())
7171       return Diag(TheCall->getBeginLoc(), diag::err_memtag_arg_must_be_pointer)
7172                << "first" << FirstArgType << Arg0->getSourceRange();
7173     TheCall->setArg(0, FirstArg.get());
7174 
7175     ExprResult SecArg = DefaultLvalueConversion(Arg1);
7176     if (SecArg.isInvalid())
7177       return true;
7178     QualType SecArgType = SecArg.get()->getType();
7179     if (!SecArgType->isIntegerType())
7180       return Diag(TheCall->getBeginLoc(), diag::err_memtag_arg_must_be_integer)
7181                << "second" << SecArgType << Arg1->getSourceRange();
7182 
7183     // Derive the return type from the pointer argument.
7184     TheCall->setType(FirstArgType);
7185     return false;
7186   }
7187 
7188   if (BuiltinID == AArch64::BI__builtin_arm_addg) {
7189     if (checkArgCount(*this, TheCall, 2))
7190       return true;
7191 
7192     Expr *Arg0 = TheCall->getArg(0);
7193     ExprResult FirstArg = DefaultFunctionArrayLvalueConversion(Arg0);
7194     if (FirstArg.isInvalid())
7195       return true;
7196     QualType FirstArgType = FirstArg.get()->getType();
7197     if (!FirstArgType->isAnyPointerType())
7198       return Diag(TheCall->getBeginLoc(), diag::err_memtag_arg_must_be_pointer)
7199                << "first" << FirstArgType << Arg0->getSourceRange();
7200     TheCall->setArg(0, FirstArg.get());
7201 
7202     // Derive the return type from the pointer argument.
7203     TheCall->setType(FirstArgType);
7204 
7205     // Second arg must be an constant in range [0,15]
7206     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 15);
7207   }
7208 
7209   if (BuiltinID == AArch64::BI__builtin_arm_gmi) {
7210     if (checkArgCount(*this, TheCall, 2))
7211       return true;
7212     Expr *Arg0 = TheCall->getArg(0);
7213     Expr *Arg1 = TheCall->getArg(1);
7214 
7215     ExprResult FirstArg = DefaultFunctionArrayLvalueConversion(Arg0);
7216     if (FirstArg.isInvalid())
7217       return true;
7218     QualType FirstArgType = FirstArg.get()->getType();
7219     if (!FirstArgType->isAnyPointerType())
7220       return Diag(TheCall->getBeginLoc(), diag::err_memtag_arg_must_be_pointer)
7221                << "first" << FirstArgType << Arg0->getSourceRange();
7222 
7223     QualType SecArgType = Arg1->getType();
7224     if (!SecArgType->isIntegerType())
7225       return Diag(TheCall->getBeginLoc(), diag::err_memtag_arg_must_be_integer)
7226                << "second" << SecArgType << Arg1->getSourceRange();
7227     TheCall->setType(Context.IntTy);
7228     return false;
7229   }
7230 
7231   if (BuiltinID == AArch64::BI__builtin_arm_ldg ||
7232       BuiltinID == AArch64::BI__builtin_arm_stg) {
7233     if (checkArgCount(*this, TheCall, 1))
7234       return true;
7235     Expr *Arg0 = TheCall->getArg(0);
7236     ExprResult FirstArg = DefaultFunctionArrayLvalueConversion(Arg0);
7237     if (FirstArg.isInvalid())
7238       return true;
7239 
7240     QualType FirstArgType = FirstArg.get()->getType();
7241     if (!FirstArgType->isAnyPointerType())
7242       return Diag(TheCall->getBeginLoc(), diag::err_memtag_arg_must_be_pointer)
7243                << "first" << FirstArgType << Arg0->getSourceRange();
7244     TheCall->setArg(0, FirstArg.get());
7245 
7246     // Derive the return type from the pointer argument.
7247     if (BuiltinID == AArch64::BI__builtin_arm_ldg)
7248       TheCall->setType(FirstArgType);
7249     return false;
7250   }
7251 
7252   if (BuiltinID == AArch64::BI__builtin_arm_subp) {
7253     Expr *ArgA = TheCall->getArg(0);
7254     Expr *ArgB = TheCall->getArg(1);
7255 
7256     ExprResult ArgExprA = DefaultFunctionArrayLvalueConversion(ArgA);
7257     ExprResult ArgExprB = DefaultFunctionArrayLvalueConversion(ArgB);
7258 
7259     if (ArgExprA.isInvalid() || ArgExprB.isInvalid())
7260       return true;
7261 
7262     QualType ArgTypeA = ArgExprA.get()->getType();
7263     QualType ArgTypeB = ArgExprB.get()->getType();
7264 
7265     auto isNull = [&] (Expr *E) -> bool {
7266       return E->isNullPointerConstant(
7267                         Context, Expr::NPC_ValueDependentIsNotNull); };
7268 
7269     // argument should be either a pointer or null
7270     if (!ArgTypeA->isAnyPointerType() && !isNull(ArgA))
7271       return Diag(TheCall->getBeginLoc(), diag::err_memtag_arg_null_or_pointer)
7272         << "first" << ArgTypeA << ArgA->getSourceRange();
7273 
7274     if (!ArgTypeB->isAnyPointerType() && !isNull(ArgB))
7275       return Diag(TheCall->getBeginLoc(), diag::err_memtag_arg_null_or_pointer)
7276         << "second" << ArgTypeB << ArgB->getSourceRange();
7277 
7278     // Ensure Pointee types are compatible
7279     if (ArgTypeA->isAnyPointerType() && !isNull(ArgA) &&
7280         ArgTypeB->isAnyPointerType() && !isNull(ArgB)) {
7281       QualType pointeeA = ArgTypeA->getPointeeType();
7282       QualType pointeeB = ArgTypeB->getPointeeType();
7283       if (!Context.typesAreCompatible(
7284              Context.getCanonicalType(pointeeA).getUnqualifiedType(),
7285              Context.getCanonicalType(pointeeB).getUnqualifiedType())) {
7286         return Diag(TheCall->getBeginLoc(), diag::err_typecheck_sub_ptr_compatible)
7287           << ArgTypeA <<  ArgTypeB << ArgA->getSourceRange()
7288           << ArgB->getSourceRange();
7289       }
7290     }
7291 
7292     // at least one argument should be pointer type
7293     if (!ArgTypeA->isAnyPointerType() && !ArgTypeB->isAnyPointerType())
7294       return Diag(TheCall->getBeginLoc(), diag::err_memtag_any2arg_pointer)
7295         <<  ArgTypeA << ArgTypeB << ArgA->getSourceRange();
7296 
7297     if (isNull(ArgA)) // adopt type of the other pointer
7298       ArgExprA = ImpCastExprToType(ArgExprA.get(), ArgTypeB, CK_NullToPointer);
7299 
7300     if (isNull(ArgB))
7301       ArgExprB = ImpCastExprToType(ArgExprB.get(), ArgTypeA, CK_NullToPointer);
7302 
7303     TheCall->setArg(0, ArgExprA.get());
7304     TheCall->setArg(1, ArgExprB.get());
7305     TheCall->setType(Context.LongLongTy);
7306     return false;
7307   }
7308   assert(false && "Unhandled ARM MTE intrinsic");
7309   return true;
7310 }
7311 
7312 /// SemaBuiltinARMSpecialReg - Handle a check if argument ArgNum of CallExpr
7313 /// TheCall is an ARM/AArch64 special register string literal.
7314 bool Sema::SemaBuiltinARMSpecialReg(unsigned BuiltinID, CallExpr *TheCall,
7315                                     int ArgNum, unsigned ExpectedFieldNum,
7316                                     bool AllowName) {
7317   bool IsARMBuiltin = BuiltinID == ARM::BI__builtin_arm_rsr64 ||
7318                       BuiltinID == ARM::BI__builtin_arm_wsr64 ||
7319                       BuiltinID == ARM::BI__builtin_arm_rsr ||
7320                       BuiltinID == ARM::BI__builtin_arm_rsrp ||
7321                       BuiltinID == ARM::BI__builtin_arm_wsr ||
7322                       BuiltinID == ARM::BI__builtin_arm_wsrp;
7323   bool IsAArch64Builtin = BuiltinID == AArch64::BI__builtin_arm_rsr64 ||
7324                           BuiltinID == AArch64::BI__builtin_arm_wsr64 ||
7325                           BuiltinID == AArch64::BI__builtin_arm_rsr ||
7326                           BuiltinID == AArch64::BI__builtin_arm_rsrp ||
7327                           BuiltinID == AArch64::BI__builtin_arm_wsr ||
7328                           BuiltinID == AArch64::BI__builtin_arm_wsrp;
7329   assert((IsARMBuiltin || IsAArch64Builtin) && "Unexpected ARM builtin.");
7330 
7331   // We can't check the value of a dependent argument.
7332   Expr *Arg = TheCall->getArg(ArgNum);
7333   if (Arg->isTypeDependent() || Arg->isValueDependent())
7334     return false;
7335 
7336   // Check if the argument is a string literal.
7337   if (!isa<StringLiteral>(Arg->IgnoreParenImpCasts()))
7338     return Diag(TheCall->getBeginLoc(), diag::err_expr_not_string_literal)
7339            << Arg->getSourceRange();
7340 
7341   // Check the type of special register given.
7342   StringRef Reg = cast<StringLiteral>(Arg->IgnoreParenImpCasts())->getString();
7343   SmallVector<StringRef, 6> Fields;
7344   Reg.split(Fields, ":");
7345 
7346   if (Fields.size() != ExpectedFieldNum && !(AllowName && Fields.size() == 1))
7347     return Diag(TheCall->getBeginLoc(), diag::err_arm_invalid_specialreg)
7348            << Arg->getSourceRange();
7349 
7350   // If the string is the name of a register then we cannot check that it is
7351   // valid here but if the string is of one the forms described in ACLE then we
7352   // can check that the supplied fields are integers and within the valid
7353   // ranges.
7354   if (Fields.size() > 1) {
7355     bool FiveFields = Fields.size() == 5;
7356 
7357     bool ValidString = true;
7358     if (IsARMBuiltin) {
7359       ValidString &= Fields[0].startswith_insensitive("cp") ||
7360                      Fields[0].startswith_insensitive("p");
7361       if (ValidString)
7362         Fields[0] = Fields[0].drop_front(
7363             Fields[0].startswith_insensitive("cp") ? 2 : 1);
7364 
7365       ValidString &= Fields[2].startswith_insensitive("c");
7366       if (ValidString)
7367         Fields[2] = Fields[2].drop_front(1);
7368 
7369       if (FiveFields) {
7370         ValidString &= Fields[3].startswith_insensitive("c");
7371         if (ValidString)
7372           Fields[3] = Fields[3].drop_front(1);
7373       }
7374     }
7375 
7376     SmallVector<int, 5> Ranges;
7377     if (FiveFields)
7378       Ranges.append({IsAArch64Builtin ? 1 : 15, 7, 15, 15, 7});
7379     else
7380       Ranges.append({15, 7, 15});
7381 
7382     for (unsigned i=0; i<Fields.size(); ++i) {
7383       int IntField;
7384       ValidString &= !Fields[i].getAsInteger(10, IntField);
7385       ValidString &= (IntField >= 0 && IntField <= Ranges[i]);
7386     }
7387 
7388     if (!ValidString)
7389       return Diag(TheCall->getBeginLoc(), diag::err_arm_invalid_specialreg)
7390              << Arg->getSourceRange();
7391   } else if (IsAArch64Builtin && Fields.size() == 1) {
7392     // If the register name is one of those that appear in the condition below
7393     // and the special register builtin being used is one of the write builtins,
7394     // then we require that the argument provided for writing to the register
7395     // is an integer constant expression. This is because it will be lowered to
7396     // an MSR (immediate) instruction, so we need to know the immediate at
7397     // compile time.
7398     if (TheCall->getNumArgs() != 2)
7399       return false;
7400 
7401     std::string RegLower = Reg.lower();
7402     if (RegLower != "spsel" && RegLower != "daifset" && RegLower != "daifclr" &&
7403         RegLower != "pan" && RegLower != "uao")
7404       return false;
7405 
7406     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 15);
7407   }
7408 
7409   return false;
7410 }
7411 
7412 /// SemaBuiltinPPCMMACall - Check the call to a PPC MMA builtin for validity.
7413 /// Emit an error and return true on failure; return false on success.
7414 /// TypeStr is a string containing the type descriptor of the value returned by
7415 /// the builtin and the descriptors of the expected type of the arguments.
7416 bool Sema::SemaBuiltinPPCMMACall(CallExpr *TheCall, const char *TypeStr) {
7417 
7418   assert((TypeStr[0] != '\0') &&
7419          "Invalid types in PPC MMA builtin declaration");
7420 
7421   unsigned Mask = 0;
7422   unsigned ArgNum = 0;
7423 
7424   // The first type in TypeStr is the type of the value returned by the
7425   // builtin. So we first read that type and change the type of TheCall.
7426   QualType type = DecodePPCMMATypeFromStr(Context, TypeStr, Mask);
7427   TheCall->setType(type);
7428 
7429   while (*TypeStr != '\0') {
7430     Mask = 0;
7431     QualType ExpectedType = DecodePPCMMATypeFromStr(Context, TypeStr, Mask);
7432     if (ArgNum >= TheCall->getNumArgs()) {
7433       ArgNum++;
7434       break;
7435     }
7436 
7437     Expr *Arg = TheCall->getArg(ArgNum);
7438     QualType ArgType = Arg->getType();
7439 
7440     if ((ExpectedType->isVoidPointerType() && !ArgType->isPointerType()) ||
7441         (!ExpectedType->isVoidPointerType() &&
7442            ArgType.getCanonicalType() != ExpectedType))
7443       return Diag(Arg->getBeginLoc(), diag::err_typecheck_convert_incompatible)
7444              << ArgType << ExpectedType << 1 << 0 << 0;
7445 
7446     // If the value of the Mask is not 0, we have a constraint in the size of
7447     // the integer argument so here we ensure the argument is a constant that
7448     // is in the valid range.
7449     if (Mask != 0 &&
7450         SemaBuiltinConstantArgRange(TheCall, ArgNum, 0, Mask, true))
7451       return true;
7452 
7453     ArgNum++;
7454   }
7455 
7456   // In case we exited early from the previous loop, there are other types to
7457   // read from TypeStr. So we need to read them all to ensure we have the right
7458   // number of arguments in TheCall and if it is not the case, to display a
7459   // better error message.
7460   while (*TypeStr != '\0') {
7461     (void) DecodePPCMMATypeFromStr(Context, TypeStr, Mask);
7462     ArgNum++;
7463   }
7464   if (checkArgCount(*this, TheCall, ArgNum))
7465     return true;
7466 
7467   return false;
7468 }
7469 
7470 /// SemaBuiltinLongjmp - Handle __builtin_longjmp(void *env[5], int val).
7471 /// This checks that the target supports __builtin_longjmp and
7472 /// that val is a constant 1.
7473 bool Sema::SemaBuiltinLongjmp(CallExpr *TheCall) {
7474   if (!Context.getTargetInfo().hasSjLjLowering())
7475     return Diag(TheCall->getBeginLoc(), diag::err_builtin_longjmp_unsupported)
7476            << SourceRange(TheCall->getBeginLoc(), TheCall->getEndLoc());
7477 
7478   Expr *Arg = TheCall->getArg(1);
7479   llvm::APSInt Result;
7480 
7481   // TODO: This is less than ideal. Overload this to take a value.
7482   if (SemaBuiltinConstantArg(TheCall, 1, Result))
7483     return true;
7484 
7485   if (Result != 1)
7486     return Diag(TheCall->getBeginLoc(), diag::err_builtin_longjmp_invalid_val)
7487            << SourceRange(Arg->getBeginLoc(), Arg->getEndLoc());
7488 
7489   return false;
7490 }
7491 
7492 /// SemaBuiltinSetjmp - Handle __builtin_setjmp(void *env[5]).
7493 /// This checks that the target supports __builtin_setjmp.
7494 bool Sema::SemaBuiltinSetjmp(CallExpr *TheCall) {
7495   if (!Context.getTargetInfo().hasSjLjLowering())
7496     return Diag(TheCall->getBeginLoc(), diag::err_builtin_setjmp_unsupported)
7497            << SourceRange(TheCall->getBeginLoc(), TheCall->getEndLoc());
7498   return false;
7499 }
7500 
7501 namespace {
7502 
7503 class UncoveredArgHandler {
7504   enum { Unknown = -1, AllCovered = -2 };
7505 
7506   signed FirstUncoveredArg = Unknown;
7507   SmallVector<const Expr *, 4> DiagnosticExprs;
7508 
7509 public:
7510   UncoveredArgHandler() = default;
7511 
7512   bool hasUncoveredArg() const {
7513     return (FirstUncoveredArg >= 0);
7514   }
7515 
7516   unsigned getUncoveredArg() const {
7517     assert(hasUncoveredArg() && "no uncovered argument");
7518     return FirstUncoveredArg;
7519   }
7520 
7521   void setAllCovered() {
7522     // A string has been found with all arguments covered, so clear out
7523     // the diagnostics.
7524     DiagnosticExprs.clear();
7525     FirstUncoveredArg = AllCovered;
7526   }
7527 
7528   void Update(signed NewFirstUncoveredArg, const Expr *StrExpr) {
7529     assert(NewFirstUncoveredArg >= 0 && "Outside range");
7530 
7531     // Don't update if a previous string covers all arguments.
7532     if (FirstUncoveredArg == AllCovered)
7533       return;
7534 
7535     // UncoveredArgHandler tracks the highest uncovered argument index
7536     // and with it all the strings that match this index.
7537     if (NewFirstUncoveredArg == FirstUncoveredArg)
7538       DiagnosticExprs.push_back(StrExpr);
7539     else if (NewFirstUncoveredArg > FirstUncoveredArg) {
7540       DiagnosticExprs.clear();
7541       DiagnosticExprs.push_back(StrExpr);
7542       FirstUncoveredArg = NewFirstUncoveredArg;
7543     }
7544   }
7545 
7546   void Diagnose(Sema &S, bool IsFunctionCall, const Expr *ArgExpr);
7547 };
7548 
7549 enum StringLiteralCheckType {
7550   SLCT_NotALiteral,
7551   SLCT_UncheckedLiteral,
7552   SLCT_CheckedLiteral
7553 };
7554 
7555 } // namespace
7556 
7557 static void sumOffsets(llvm::APSInt &Offset, llvm::APSInt Addend,
7558                                      BinaryOperatorKind BinOpKind,
7559                                      bool AddendIsRight) {
7560   unsigned BitWidth = Offset.getBitWidth();
7561   unsigned AddendBitWidth = Addend.getBitWidth();
7562   // There might be negative interim results.
7563   if (Addend.isUnsigned()) {
7564     Addend = Addend.zext(++AddendBitWidth);
7565     Addend.setIsSigned(true);
7566   }
7567   // Adjust the bit width of the APSInts.
7568   if (AddendBitWidth > BitWidth) {
7569     Offset = Offset.sext(AddendBitWidth);
7570     BitWidth = AddendBitWidth;
7571   } else if (BitWidth > AddendBitWidth) {
7572     Addend = Addend.sext(BitWidth);
7573   }
7574 
7575   bool Ov = false;
7576   llvm::APSInt ResOffset = Offset;
7577   if (BinOpKind == BO_Add)
7578     ResOffset = Offset.sadd_ov(Addend, Ov);
7579   else {
7580     assert(AddendIsRight && BinOpKind == BO_Sub &&
7581            "operator must be add or sub with addend on the right");
7582     ResOffset = Offset.ssub_ov(Addend, Ov);
7583   }
7584 
7585   // We add an offset to a pointer here so we should support an offset as big as
7586   // possible.
7587   if (Ov) {
7588     assert(BitWidth <= std::numeric_limits<unsigned>::max() / 2 &&
7589            "index (intermediate) result too big");
7590     Offset = Offset.sext(2 * BitWidth);
7591     sumOffsets(Offset, Addend, BinOpKind, AddendIsRight);
7592     return;
7593   }
7594 
7595   Offset = ResOffset;
7596 }
7597 
7598 namespace {
7599 
7600 // This is a wrapper class around StringLiteral to support offsetted string
7601 // literals as format strings. It takes the offset into account when returning
7602 // the string and its length or the source locations to display notes correctly.
7603 class FormatStringLiteral {
7604   const StringLiteral *FExpr;
7605   int64_t Offset;
7606 
7607  public:
7608   FormatStringLiteral(const StringLiteral *fexpr, int64_t Offset = 0)
7609       : FExpr(fexpr), Offset(Offset) {}
7610 
7611   StringRef getString() const {
7612     return FExpr->getString().drop_front(Offset);
7613   }
7614 
7615   unsigned getByteLength() const {
7616     return FExpr->getByteLength() - getCharByteWidth() * Offset;
7617   }
7618 
7619   unsigned getLength() const { return FExpr->getLength() - Offset; }
7620   unsigned getCharByteWidth() const { return FExpr->getCharByteWidth(); }
7621 
7622   StringLiteral::StringKind getKind() const { return FExpr->getKind(); }
7623 
7624   QualType getType() const { return FExpr->getType(); }
7625 
7626   bool isAscii() const { return FExpr->isAscii(); }
7627   bool isWide() const { return FExpr->isWide(); }
7628   bool isUTF8() const { return FExpr->isUTF8(); }
7629   bool isUTF16() const { return FExpr->isUTF16(); }
7630   bool isUTF32() const { return FExpr->isUTF32(); }
7631   bool isPascal() const { return FExpr->isPascal(); }
7632 
7633   SourceLocation getLocationOfByte(
7634       unsigned ByteNo, const SourceManager &SM, const LangOptions &Features,
7635       const TargetInfo &Target, unsigned *StartToken = nullptr,
7636       unsigned *StartTokenByteOffset = nullptr) const {
7637     return FExpr->getLocationOfByte(ByteNo + Offset, SM, Features, Target,
7638                                     StartToken, StartTokenByteOffset);
7639   }
7640 
7641   SourceLocation getBeginLoc() const LLVM_READONLY {
7642     return FExpr->getBeginLoc().getLocWithOffset(Offset);
7643   }
7644 
7645   SourceLocation getEndLoc() const LLVM_READONLY { return FExpr->getEndLoc(); }
7646 };
7647 
7648 }  // namespace
7649 
7650 static void CheckFormatString(Sema &S, const FormatStringLiteral *FExpr,
7651                               const Expr *OrigFormatExpr,
7652                               ArrayRef<const Expr *> Args,
7653                               bool HasVAListArg, unsigned format_idx,
7654                               unsigned firstDataArg,
7655                               Sema::FormatStringType Type,
7656                               bool inFunctionCall,
7657                               Sema::VariadicCallType CallType,
7658                               llvm::SmallBitVector &CheckedVarArgs,
7659                               UncoveredArgHandler &UncoveredArg,
7660                               bool IgnoreStringsWithoutSpecifiers);
7661 
7662 // Determine if an expression is a string literal or constant string.
7663 // If this function returns false on the arguments to a function expecting a
7664 // format string, we will usually need to emit a warning.
7665 // True string literals are then checked by CheckFormatString.
7666 static StringLiteralCheckType
7667 checkFormatStringExpr(Sema &S, const Expr *E, ArrayRef<const Expr *> Args,
7668                       bool HasVAListArg, unsigned format_idx,
7669                       unsigned firstDataArg, Sema::FormatStringType Type,
7670                       Sema::VariadicCallType CallType, bool InFunctionCall,
7671                       llvm::SmallBitVector &CheckedVarArgs,
7672                       UncoveredArgHandler &UncoveredArg,
7673                       llvm::APSInt Offset,
7674                       bool IgnoreStringsWithoutSpecifiers = false) {
7675   if (S.isConstantEvaluated())
7676     return SLCT_NotALiteral;
7677  tryAgain:
7678   assert(Offset.isSigned() && "invalid offset");
7679 
7680   if (E->isTypeDependent() || E->isValueDependent())
7681     return SLCT_NotALiteral;
7682 
7683   E = E->IgnoreParenCasts();
7684 
7685   if (E->isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull))
7686     // Technically -Wformat-nonliteral does not warn about this case.
7687     // The behavior of printf and friends in this case is implementation
7688     // dependent.  Ideally if the format string cannot be null then
7689     // it should have a 'nonnull' attribute in the function prototype.
7690     return SLCT_UncheckedLiteral;
7691 
7692   switch (E->getStmtClass()) {
7693   case Stmt::BinaryConditionalOperatorClass:
7694   case Stmt::ConditionalOperatorClass: {
7695     // The expression is a literal if both sub-expressions were, and it was
7696     // completely checked only if both sub-expressions were checked.
7697     const AbstractConditionalOperator *C =
7698         cast<AbstractConditionalOperator>(E);
7699 
7700     // Determine whether it is necessary to check both sub-expressions, for
7701     // example, because the condition expression is a constant that can be
7702     // evaluated at compile time.
7703     bool CheckLeft = true, CheckRight = true;
7704 
7705     bool Cond;
7706     if (C->getCond()->EvaluateAsBooleanCondition(Cond, S.getASTContext(),
7707                                                  S.isConstantEvaluated())) {
7708       if (Cond)
7709         CheckRight = false;
7710       else
7711         CheckLeft = false;
7712     }
7713 
7714     // We need to maintain the offsets for the right and the left hand side
7715     // separately to check if every possible indexed expression is a valid
7716     // string literal. They might have different offsets for different string
7717     // literals in the end.
7718     StringLiteralCheckType Left;
7719     if (!CheckLeft)
7720       Left = SLCT_UncheckedLiteral;
7721     else {
7722       Left = checkFormatStringExpr(S, C->getTrueExpr(), Args,
7723                                    HasVAListArg, format_idx, firstDataArg,
7724                                    Type, CallType, InFunctionCall,
7725                                    CheckedVarArgs, UncoveredArg, Offset,
7726                                    IgnoreStringsWithoutSpecifiers);
7727       if (Left == SLCT_NotALiteral || !CheckRight) {
7728         return Left;
7729       }
7730     }
7731 
7732     StringLiteralCheckType Right = checkFormatStringExpr(
7733         S, C->getFalseExpr(), Args, HasVAListArg, format_idx, firstDataArg,
7734         Type, CallType, InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
7735         IgnoreStringsWithoutSpecifiers);
7736 
7737     return (CheckLeft && Left < Right) ? Left : Right;
7738   }
7739 
7740   case Stmt::ImplicitCastExprClass:
7741     E = cast<ImplicitCastExpr>(E)->getSubExpr();
7742     goto tryAgain;
7743 
7744   case Stmt::OpaqueValueExprClass:
7745     if (const Expr *src = cast<OpaqueValueExpr>(E)->getSourceExpr()) {
7746       E = src;
7747       goto tryAgain;
7748     }
7749     return SLCT_NotALiteral;
7750 
7751   case Stmt::PredefinedExprClass:
7752     // While __func__, etc., are technically not string literals, they
7753     // cannot contain format specifiers and thus are not a security
7754     // liability.
7755     return SLCT_UncheckedLiteral;
7756 
7757   case Stmt::DeclRefExprClass: {
7758     const DeclRefExpr *DR = cast<DeclRefExpr>(E);
7759 
7760     // As an exception, do not flag errors for variables binding to
7761     // const string literals.
7762     if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl())) {
7763       bool isConstant = false;
7764       QualType T = DR->getType();
7765 
7766       if (const ArrayType *AT = S.Context.getAsArrayType(T)) {
7767         isConstant = AT->getElementType().isConstant(S.Context);
7768       } else if (const PointerType *PT = T->getAs<PointerType>()) {
7769         isConstant = T.isConstant(S.Context) &&
7770                      PT->getPointeeType().isConstant(S.Context);
7771       } else if (T->isObjCObjectPointerType()) {
7772         // In ObjC, there is usually no "const ObjectPointer" type,
7773         // so don't check if the pointee type is constant.
7774         isConstant = T.isConstant(S.Context);
7775       }
7776 
7777       if (isConstant) {
7778         if (const Expr *Init = VD->getAnyInitializer()) {
7779           // Look through initializers like const char c[] = { "foo" }
7780           if (const InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) {
7781             if (InitList->isStringLiteralInit())
7782               Init = InitList->getInit(0)->IgnoreParenImpCasts();
7783           }
7784           return checkFormatStringExpr(S, Init, Args,
7785                                        HasVAListArg, format_idx,
7786                                        firstDataArg, Type, CallType,
7787                                        /*InFunctionCall*/ false, CheckedVarArgs,
7788                                        UncoveredArg, Offset);
7789         }
7790       }
7791 
7792       // For vprintf* functions (i.e., HasVAListArg==true), we add a
7793       // special check to see if the format string is a function parameter
7794       // of the function calling the printf function.  If the function
7795       // has an attribute indicating it is a printf-like function, then we
7796       // should suppress warnings concerning non-literals being used in a call
7797       // to a vprintf function.  For example:
7798       //
7799       // void
7800       // logmessage(char const *fmt __attribute__ (format (printf, 1, 2)), ...){
7801       //      va_list ap;
7802       //      va_start(ap, fmt);
7803       //      vprintf(fmt, ap);  // Do NOT emit a warning about "fmt".
7804       //      ...
7805       // }
7806       if (HasVAListArg) {
7807         if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(VD)) {
7808           if (const NamedDecl *ND = dyn_cast<NamedDecl>(PV->getDeclContext())) {
7809             int PVIndex = PV->getFunctionScopeIndex() + 1;
7810             for (const auto *PVFormat : ND->specific_attrs<FormatAttr>()) {
7811               // adjust for implicit parameter
7812               if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND))
7813                 if (MD->isInstance())
7814                   ++PVIndex;
7815               // We also check if the formats are compatible.
7816               // We can't pass a 'scanf' string to a 'printf' function.
7817               if (PVIndex == PVFormat->getFormatIdx() &&
7818                   Type == S.GetFormatStringType(PVFormat))
7819                 return SLCT_UncheckedLiteral;
7820             }
7821           }
7822         }
7823       }
7824     }
7825 
7826     return SLCT_NotALiteral;
7827   }
7828 
7829   case Stmt::CallExprClass:
7830   case Stmt::CXXMemberCallExprClass: {
7831     const CallExpr *CE = cast<CallExpr>(E);
7832     if (const NamedDecl *ND = dyn_cast_or_null<NamedDecl>(CE->getCalleeDecl())) {
7833       bool IsFirst = true;
7834       StringLiteralCheckType CommonResult;
7835       for (const auto *FA : ND->specific_attrs<FormatArgAttr>()) {
7836         const Expr *Arg = CE->getArg(FA->getFormatIdx().getASTIndex());
7837         StringLiteralCheckType Result = checkFormatStringExpr(
7838             S, Arg, Args, HasVAListArg, format_idx, firstDataArg, Type,
7839             CallType, InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
7840             IgnoreStringsWithoutSpecifiers);
7841         if (IsFirst) {
7842           CommonResult = Result;
7843           IsFirst = false;
7844         }
7845       }
7846       if (!IsFirst)
7847         return CommonResult;
7848 
7849       if (const auto *FD = dyn_cast<FunctionDecl>(ND)) {
7850         unsigned BuiltinID = FD->getBuiltinID();
7851         if (BuiltinID == Builtin::BI__builtin___CFStringMakeConstantString ||
7852             BuiltinID == Builtin::BI__builtin___NSStringMakeConstantString) {
7853           const Expr *Arg = CE->getArg(0);
7854           return checkFormatStringExpr(S, Arg, Args,
7855                                        HasVAListArg, format_idx,
7856                                        firstDataArg, Type, CallType,
7857                                        InFunctionCall, CheckedVarArgs,
7858                                        UncoveredArg, Offset,
7859                                        IgnoreStringsWithoutSpecifiers);
7860         }
7861       }
7862     }
7863 
7864     return SLCT_NotALiteral;
7865   }
7866   case Stmt::ObjCMessageExprClass: {
7867     const auto *ME = cast<ObjCMessageExpr>(E);
7868     if (const auto *MD = ME->getMethodDecl()) {
7869       if (const auto *FA = MD->getAttr<FormatArgAttr>()) {
7870         // As a special case heuristic, if we're using the method -[NSBundle
7871         // localizedStringForKey:value:table:], ignore any key strings that lack
7872         // format specifiers. The idea is that if the key doesn't have any
7873         // format specifiers then its probably just a key to map to the
7874         // localized strings. If it does have format specifiers though, then its
7875         // likely that the text of the key is the format string in the
7876         // programmer's language, and should be checked.
7877         const ObjCInterfaceDecl *IFace;
7878         if (MD->isInstanceMethod() && (IFace = MD->getClassInterface()) &&
7879             IFace->getIdentifier()->isStr("NSBundle") &&
7880             MD->getSelector().isKeywordSelector(
7881                 {"localizedStringForKey", "value", "table"})) {
7882           IgnoreStringsWithoutSpecifiers = true;
7883         }
7884 
7885         const Expr *Arg = ME->getArg(FA->getFormatIdx().getASTIndex());
7886         return checkFormatStringExpr(
7887             S, Arg, Args, HasVAListArg, format_idx, firstDataArg, Type,
7888             CallType, InFunctionCall, CheckedVarArgs, UncoveredArg, Offset,
7889             IgnoreStringsWithoutSpecifiers);
7890       }
7891     }
7892 
7893     return SLCT_NotALiteral;
7894   }
7895   case Stmt::ObjCStringLiteralClass:
7896   case Stmt::StringLiteralClass: {
7897     const StringLiteral *StrE = nullptr;
7898 
7899     if (const ObjCStringLiteral *ObjCFExpr = dyn_cast<ObjCStringLiteral>(E))
7900       StrE = ObjCFExpr->getString();
7901     else
7902       StrE = cast<StringLiteral>(E);
7903 
7904     if (StrE) {
7905       if (Offset.isNegative() || Offset > StrE->getLength()) {
7906         // TODO: It would be better to have an explicit warning for out of
7907         // bounds literals.
7908         return SLCT_NotALiteral;
7909       }
7910       FormatStringLiteral FStr(StrE, Offset.sextOrTrunc(64).getSExtValue());
7911       CheckFormatString(S, &FStr, E, Args, HasVAListArg, format_idx,
7912                         firstDataArg, Type, InFunctionCall, CallType,
7913                         CheckedVarArgs, UncoveredArg,
7914                         IgnoreStringsWithoutSpecifiers);
7915       return SLCT_CheckedLiteral;
7916     }
7917 
7918     return SLCT_NotALiteral;
7919   }
7920   case Stmt::BinaryOperatorClass: {
7921     const BinaryOperator *BinOp = cast<BinaryOperator>(E);
7922 
7923     // A string literal + an int offset is still a string literal.
7924     if (BinOp->isAdditiveOp()) {
7925       Expr::EvalResult LResult, RResult;
7926 
7927       bool LIsInt = BinOp->getLHS()->EvaluateAsInt(
7928           LResult, S.Context, Expr::SE_NoSideEffects, S.isConstantEvaluated());
7929       bool RIsInt = BinOp->getRHS()->EvaluateAsInt(
7930           RResult, S.Context, Expr::SE_NoSideEffects, S.isConstantEvaluated());
7931 
7932       if (LIsInt != RIsInt) {
7933         BinaryOperatorKind BinOpKind = BinOp->getOpcode();
7934 
7935         if (LIsInt) {
7936           if (BinOpKind == BO_Add) {
7937             sumOffsets(Offset, LResult.Val.getInt(), BinOpKind, RIsInt);
7938             E = BinOp->getRHS();
7939             goto tryAgain;
7940           }
7941         } else {
7942           sumOffsets(Offset, RResult.Val.getInt(), BinOpKind, RIsInt);
7943           E = BinOp->getLHS();
7944           goto tryAgain;
7945         }
7946       }
7947     }
7948 
7949     return SLCT_NotALiteral;
7950   }
7951   case Stmt::UnaryOperatorClass: {
7952     const UnaryOperator *UnaOp = cast<UnaryOperator>(E);
7953     auto ASE = dyn_cast<ArraySubscriptExpr>(UnaOp->getSubExpr());
7954     if (UnaOp->getOpcode() == UO_AddrOf && ASE) {
7955       Expr::EvalResult IndexResult;
7956       if (ASE->getRHS()->EvaluateAsInt(IndexResult, S.Context,
7957                                        Expr::SE_NoSideEffects,
7958                                        S.isConstantEvaluated())) {
7959         sumOffsets(Offset, IndexResult.Val.getInt(), BO_Add,
7960                    /*RHS is int*/ true);
7961         E = ASE->getBase();
7962         goto tryAgain;
7963       }
7964     }
7965 
7966     return SLCT_NotALiteral;
7967   }
7968 
7969   default:
7970     return SLCT_NotALiteral;
7971   }
7972 }
7973 
7974 Sema::FormatStringType Sema::GetFormatStringType(const FormatAttr *Format) {
7975   return llvm::StringSwitch<FormatStringType>(Format->getType()->getName())
7976       .Case("scanf", FST_Scanf)
7977       .Cases("printf", "printf0", FST_Printf)
7978       .Cases("NSString", "CFString", FST_NSString)
7979       .Case("strftime", FST_Strftime)
7980       .Case("strfmon", FST_Strfmon)
7981       .Cases("kprintf", "cmn_err", "vcmn_err", "zcmn_err", FST_Kprintf)
7982       .Case("freebsd_kprintf", FST_FreeBSDKPrintf)
7983       .Case("os_trace", FST_OSLog)
7984       .Case("os_log", FST_OSLog)
7985       .Default(FST_Unknown);
7986 }
7987 
7988 /// CheckFormatArguments - Check calls to printf and scanf (and similar
7989 /// functions) for correct use of format strings.
7990 /// Returns true if a format string has been fully checked.
7991 bool Sema::CheckFormatArguments(const FormatAttr *Format,
7992                                 ArrayRef<const Expr *> Args,
7993                                 bool IsCXXMember,
7994                                 VariadicCallType CallType,
7995                                 SourceLocation Loc, SourceRange Range,
7996                                 llvm::SmallBitVector &CheckedVarArgs) {
7997   FormatStringInfo FSI;
7998   if (getFormatStringInfo(Format, IsCXXMember, &FSI))
7999     return CheckFormatArguments(Args, FSI.HasVAListArg, FSI.FormatIdx,
8000                                 FSI.FirstDataArg, GetFormatStringType(Format),
8001                                 CallType, Loc, Range, CheckedVarArgs);
8002   return false;
8003 }
8004 
8005 bool Sema::CheckFormatArguments(ArrayRef<const Expr *> Args,
8006                                 bool HasVAListArg, unsigned format_idx,
8007                                 unsigned firstDataArg, FormatStringType Type,
8008                                 VariadicCallType CallType,
8009                                 SourceLocation Loc, SourceRange Range,
8010                                 llvm::SmallBitVector &CheckedVarArgs) {
8011   // CHECK: printf/scanf-like function is called with no format string.
8012   if (format_idx >= Args.size()) {
8013     Diag(Loc, diag::warn_missing_format_string) << Range;
8014     return false;
8015   }
8016 
8017   const Expr *OrigFormatExpr = Args[format_idx]->IgnoreParenCasts();
8018 
8019   // CHECK: format string is not a string literal.
8020   //
8021   // Dynamically generated format strings are difficult to
8022   // automatically vet at compile time.  Requiring that format strings
8023   // are string literals: (1) permits the checking of format strings by
8024   // the compiler and thereby (2) can practically remove the source of
8025   // many format string exploits.
8026 
8027   // Format string can be either ObjC string (e.g. @"%d") or
8028   // C string (e.g. "%d")
8029   // ObjC string uses the same format specifiers as C string, so we can use
8030   // the same format string checking logic for both ObjC and C strings.
8031   UncoveredArgHandler UncoveredArg;
8032   StringLiteralCheckType CT =
8033       checkFormatStringExpr(*this, OrigFormatExpr, Args, HasVAListArg,
8034                             format_idx, firstDataArg, Type, CallType,
8035                             /*IsFunctionCall*/ true, CheckedVarArgs,
8036                             UncoveredArg,
8037                             /*no string offset*/ llvm::APSInt(64, false) = 0);
8038 
8039   // Generate a diagnostic where an uncovered argument is detected.
8040   if (UncoveredArg.hasUncoveredArg()) {
8041     unsigned ArgIdx = UncoveredArg.getUncoveredArg() + firstDataArg;
8042     assert(ArgIdx < Args.size() && "ArgIdx outside bounds");
8043     UncoveredArg.Diagnose(*this, /*IsFunctionCall*/true, Args[ArgIdx]);
8044   }
8045 
8046   if (CT != SLCT_NotALiteral)
8047     // Literal format string found, check done!
8048     return CT == SLCT_CheckedLiteral;
8049 
8050   // Strftime is particular as it always uses a single 'time' argument,
8051   // so it is safe to pass a non-literal string.
8052   if (Type == FST_Strftime)
8053     return false;
8054 
8055   // Do not emit diag when the string param is a macro expansion and the
8056   // format is either NSString or CFString. This is a hack to prevent
8057   // diag when using the NSLocalizedString and CFCopyLocalizedString macros
8058   // which are usually used in place of NS and CF string literals.
8059   SourceLocation FormatLoc = Args[format_idx]->getBeginLoc();
8060   if (Type == FST_NSString && SourceMgr.isInSystemMacro(FormatLoc))
8061     return false;
8062 
8063   // If there are no arguments specified, warn with -Wformat-security, otherwise
8064   // warn only with -Wformat-nonliteral.
8065   if (Args.size() == firstDataArg) {
8066     Diag(FormatLoc, diag::warn_format_nonliteral_noargs)
8067       << OrigFormatExpr->getSourceRange();
8068     switch (Type) {
8069     default:
8070       break;
8071     case FST_Kprintf:
8072     case FST_FreeBSDKPrintf:
8073     case FST_Printf:
8074       Diag(FormatLoc, diag::note_format_security_fixit)
8075         << FixItHint::CreateInsertion(FormatLoc, "\"%s\", ");
8076       break;
8077     case FST_NSString:
8078       Diag(FormatLoc, diag::note_format_security_fixit)
8079         << FixItHint::CreateInsertion(FormatLoc, "@\"%@\", ");
8080       break;
8081     }
8082   } else {
8083     Diag(FormatLoc, diag::warn_format_nonliteral)
8084       << OrigFormatExpr->getSourceRange();
8085   }
8086   return false;
8087 }
8088 
8089 namespace {
8090 
8091 class CheckFormatHandler : public analyze_format_string::FormatStringHandler {
8092 protected:
8093   Sema &S;
8094   const FormatStringLiteral *FExpr;
8095   const Expr *OrigFormatExpr;
8096   const Sema::FormatStringType FSType;
8097   const unsigned FirstDataArg;
8098   const unsigned NumDataArgs;
8099   const char *Beg; // Start of format string.
8100   const bool HasVAListArg;
8101   ArrayRef<const Expr *> Args;
8102   unsigned FormatIdx;
8103   llvm::SmallBitVector CoveredArgs;
8104   bool usesPositionalArgs = false;
8105   bool atFirstArg = true;
8106   bool inFunctionCall;
8107   Sema::VariadicCallType CallType;
8108   llvm::SmallBitVector &CheckedVarArgs;
8109   UncoveredArgHandler &UncoveredArg;
8110 
8111 public:
8112   CheckFormatHandler(Sema &s, const FormatStringLiteral *fexpr,
8113                      const Expr *origFormatExpr,
8114                      const Sema::FormatStringType type, unsigned firstDataArg,
8115                      unsigned numDataArgs, const char *beg, bool hasVAListArg,
8116                      ArrayRef<const Expr *> Args, unsigned formatIdx,
8117                      bool inFunctionCall, Sema::VariadicCallType callType,
8118                      llvm::SmallBitVector &CheckedVarArgs,
8119                      UncoveredArgHandler &UncoveredArg)
8120       : S(s), FExpr(fexpr), OrigFormatExpr(origFormatExpr), FSType(type),
8121         FirstDataArg(firstDataArg), NumDataArgs(numDataArgs), Beg(beg),
8122         HasVAListArg(hasVAListArg), Args(Args), FormatIdx(formatIdx),
8123         inFunctionCall(inFunctionCall), CallType(callType),
8124         CheckedVarArgs(CheckedVarArgs), UncoveredArg(UncoveredArg) {
8125     CoveredArgs.resize(numDataArgs);
8126     CoveredArgs.reset();
8127   }
8128 
8129   void DoneProcessing();
8130 
8131   void HandleIncompleteSpecifier(const char *startSpecifier,
8132                                  unsigned specifierLen) override;
8133 
8134   void HandleInvalidLengthModifier(
8135                            const analyze_format_string::FormatSpecifier &FS,
8136                            const analyze_format_string::ConversionSpecifier &CS,
8137                            const char *startSpecifier, unsigned specifierLen,
8138                            unsigned DiagID);
8139 
8140   void HandleNonStandardLengthModifier(
8141                     const analyze_format_string::FormatSpecifier &FS,
8142                     const char *startSpecifier, unsigned specifierLen);
8143 
8144   void HandleNonStandardConversionSpecifier(
8145                     const analyze_format_string::ConversionSpecifier &CS,
8146                     const char *startSpecifier, unsigned specifierLen);
8147 
8148   void HandlePosition(const char *startPos, unsigned posLen) override;
8149 
8150   void HandleInvalidPosition(const char *startSpecifier,
8151                              unsigned specifierLen,
8152                              analyze_format_string::PositionContext p) override;
8153 
8154   void HandleZeroPosition(const char *startPos, unsigned posLen) override;
8155 
8156   void HandleNullChar(const char *nullCharacter) override;
8157 
8158   template <typename Range>
8159   static void
8160   EmitFormatDiagnostic(Sema &S, bool inFunctionCall, const Expr *ArgumentExpr,
8161                        const PartialDiagnostic &PDiag, SourceLocation StringLoc,
8162                        bool IsStringLocation, Range StringRange,
8163                        ArrayRef<FixItHint> Fixit = None);
8164 
8165 protected:
8166   bool HandleInvalidConversionSpecifier(unsigned argIndex, SourceLocation Loc,
8167                                         const char *startSpec,
8168                                         unsigned specifierLen,
8169                                         const char *csStart, unsigned csLen);
8170 
8171   void HandlePositionalNonpositionalArgs(SourceLocation Loc,
8172                                          const char *startSpec,
8173                                          unsigned specifierLen);
8174 
8175   SourceRange getFormatStringRange();
8176   CharSourceRange getSpecifierRange(const char *startSpecifier,
8177                                     unsigned specifierLen);
8178   SourceLocation getLocationOfByte(const char *x);
8179 
8180   const Expr *getDataArg(unsigned i) const;
8181 
8182   bool CheckNumArgs(const analyze_format_string::FormatSpecifier &FS,
8183                     const analyze_format_string::ConversionSpecifier &CS,
8184                     const char *startSpecifier, unsigned specifierLen,
8185                     unsigned argIndex);
8186 
8187   template <typename Range>
8188   void EmitFormatDiagnostic(PartialDiagnostic PDiag, SourceLocation StringLoc,
8189                             bool IsStringLocation, Range StringRange,
8190                             ArrayRef<FixItHint> Fixit = None);
8191 };
8192 
8193 } // namespace
8194 
8195 SourceRange CheckFormatHandler::getFormatStringRange() {
8196   return OrigFormatExpr->getSourceRange();
8197 }
8198 
8199 CharSourceRange CheckFormatHandler::
8200 getSpecifierRange(const char *startSpecifier, unsigned specifierLen) {
8201   SourceLocation Start = getLocationOfByte(startSpecifier);
8202   SourceLocation End   = getLocationOfByte(startSpecifier + specifierLen - 1);
8203 
8204   // Advance the end SourceLocation by one due to half-open ranges.
8205   End = End.getLocWithOffset(1);
8206 
8207   return CharSourceRange::getCharRange(Start, End);
8208 }
8209 
8210 SourceLocation CheckFormatHandler::getLocationOfByte(const char *x) {
8211   return FExpr->getLocationOfByte(x - Beg, S.getSourceManager(),
8212                                   S.getLangOpts(), S.Context.getTargetInfo());
8213 }
8214 
8215 void CheckFormatHandler::HandleIncompleteSpecifier(const char *startSpecifier,
8216                                                    unsigned specifierLen){
8217   EmitFormatDiagnostic(S.PDiag(diag::warn_printf_incomplete_specifier),
8218                        getLocationOfByte(startSpecifier),
8219                        /*IsStringLocation*/true,
8220                        getSpecifierRange(startSpecifier, specifierLen));
8221 }
8222 
8223 void CheckFormatHandler::HandleInvalidLengthModifier(
8224     const analyze_format_string::FormatSpecifier &FS,
8225     const analyze_format_string::ConversionSpecifier &CS,
8226     const char *startSpecifier, unsigned specifierLen, unsigned DiagID) {
8227   using namespace analyze_format_string;
8228 
8229   const LengthModifier &LM = FS.getLengthModifier();
8230   CharSourceRange LMRange = getSpecifierRange(LM.getStart(), LM.getLength());
8231 
8232   // See if we know how to fix this length modifier.
8233   Optional<LengthModifier> FixedLM = FS.getCorrectedLengthModifier();
8234   if (FixedLM) {
8235     EmitFormatDiagnostic(S.PDiag(DiagID) << LM.toString() << CS.toString(),
8236                          getLocationOfByte(LM.getStart()),
8237                          /*IsStringLocation*/true,
8238                          getSpecifierRange(startSpecifier, specifierLen));
8239 
8240     S.Diag(getLocationOfByte(LM.getStart()), diag::note_format_fix_specifier)
8241       << FixedLM->toString()
8242       << FixItHint::CreateReplacement(LMRange, FixedLM->toString());
8243 
8244   } else {
8245     FixItHint Hint;
8246     if (DiagID == diag::warn_format_nonsensical_length)
8247       Hint = FixItHint::CreateRemoval(LMRange);
8248 
8249     EmitFormatDiagnostic(S.PDiag(DiagID) << LM.toString() << CS.toString(),
8250                          getLocationOfByte(LM.getStart()),
8251                          /*IsStringLocation*/true,
8252                          getSpecifierRange(startSpecifier, specifierLen),
8253                          Hint);
8254   }
8255 }
8256 
8257 void CheckFormatHandler::HandleNonStandardLengthModifier(
8258     const analyze_format_string::FormatSpecifier &FS,
8259     const char *startSpecifier, unsigned specifierLen) {
8260   using namespace analyze_format_string;
8261 
8262   const LengthModifier &LM = FS.getLengthModifier();
8263   CharSourceRange LMRange = getSpecifierRange(LM.getStart(), LM.getLength());
8264 
8265   // See if we know how to fix this length modifier.
8266   Optional<LengthModifier> FixedLM = FS.getCorrectedLengthModifier();
8267   if (FixedLM) {
8268     EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard)
8269                            << LM.toString() << 0,
8270                          getLocationOfByte(LM.getStart()),
8271                          /*IsStringLocation*/true,
8272                          getSpecifierRange(startSpecifier, specifierLen));
8273 
8274     S.Diag(getLocationOfByte(LM.getStart()), diag::note_format_fix_specifier)
8275       << FixedLM->toString()
8276       << FixItHint::CreateReplacement(LMRange, FixedLM->toString());
8277 
8278   } else {
8279     EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard)
8280                            << LM.toString() << 0,
8281                          getLocationOfByte(LM.getStart()),
8282                          /*IsStringLocation*/true,
8283                          getSpecifierRange(startSpecifier, specifierLen));
8284   }
8285 }
8286 
8287 void CheckFormatHandler::HandleNonStandardConversionSpecifier(
8288     const analyze_format_string::ConversionSpecifier &CS,
8289     const char *startSpecifier, unsigned specifierLen) {
8290   using namespace analyze_format_string;
8291 
8292   // See if we know how to fix this conversion specifier.
8293   Optional<ConversionSpecifier> FixedCS = CS.getStandardSpecifier();
8294   if (FixedCS) {
8295     EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard)
8296                           << CS.toString() << /*conversion specifier*/1,
8297                          getLocationOfByte(CS.getStart()),
8298                          /*IsStringLocation*/true,
8299                          getSpecifierRange(startSpecifier, specifierLen));
8300 
8301     CharSourceRange CSRange = getSpecifierRange(CS.getStart(), CS.getLength());
8302     S.Diag(getLocationOfByte(CS.getStart()), diag::note_format_fix_specifier)
8303       << FixedCS->toString()
8304       << FixItHint::CreateReplacement(CSRange, FixedCS->toString());
8305   } else {
8306     EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard)
8307                           << CS.toString() << /*conversion specifier*/1,
8308                          getLocationOfByte(CS.getStart()),
8309                          /*IsStringLocation*/true,
8310                          getSpecifierRange(startSpecifier, specifierLen));
8311   }
8312 }
8313 
8314 void CheckFormatHandler::HandlePosition(const char *startPos,
8315                                         unsigned posLen) {
8316   EmitFormatDiagnostic(S.PDiag(diag::warn_format_non_standard_positional_arg),
8317                                getLocationOfByte(startPos),
8318                                /*IsStringLocation*/true,
8319                                getSpecifierRange(startPos, posLen));
8320 }
8321 
8322 void
8323 CheckFormatHandler::HandleInvalidPosition(const char *startPos, unsigned posLen,
8324                                      analyze_format_string::PositionContext p) {
8325   EmitFormatDiagnostic(S.PDiag(diag::warn_format_invalid_positional_specifier)
8326                          << (unsigned) p,
8327                        getLocationOfByte(startPos), /*IsStringLocation*/true,
8328                        getSpecifierRange(startPos, posLen));
8329 }
8330 
8331 void CheckFormatHandler::HandleZeroPosition(const char *startPos,
8332                                             unsigned posLen) {
8333   EmitFormatDiagnostic(S.PDiag(diag::warn_format_zero_positional_specifier),
8334                                getLocationOfByte(startPos),
8335                                /*IsStringLocation*/true,
8336                                getSpecifierRange(startPos, posLen));
8337 }
8338 
8339 void CheckFormatHandler::HandleNullChar(const char *nullCharacter) {
8340   if (!isa<ObjCStringLiteral>(OrigFormatExpr)) {
8341     // The presence of a null character is likely an error.
8342     EmitFormatDiagnostic(
8343       S.PDiag(diag::warn_printf_format_string_contains_null_char),
8344       getLocationOfByte(nullCharacter), /*IsStringLocation*/true,
8345       getFormatStringRange());
8346   }
8347 }
8348 
8349 // Note that this may return NULL if there was an error parsing or building
8350 // one of the argument expressions.
8351 const Expr *CheckFormatHandler::getDataArg(unsigned i) const {
8352   return Args[FirstDataArg + i];
8353 }
8354 
8355 void CheckFormatHandler::DoneProcessing() {
8356   // Does the number of data arguments exceed the number of
8357   // format conversions in the format string?
8358   if (!HasVAListArg) {
8359       // Find any arguments that weren't covered.
8360     CoveredArgs.flip();
8361     signed notCoveredArg = CoveredArgs.find_first();
8362     if (notCoveredArg >= 0) {
8363       assert((unsigned)notCoveredArg < NumDataArgs);
8364       UncoveredArg.Update(notCoveredArg, OrigFormatExpr);
8365     } else {
8366       UncoveredArg.setAllCovered();
8367     }
8368   }
8369 }
8370 
8371 void UncoveredArgHandler::Diagnose(Sema &S, bool IsFunctionCall,
8372                                    const Expr *ArgExpr) {
8373   assert(hasUncoveredArg() && DiagnosticExprs.size() > 0 &&
8374          "Invalid state");
8375 
8376   if (!ArgExpr)
8377     return;
8378 
8379   SourceLocation Loc = ArgExpr->getBeginLoc();
8380 
8381   if (S.getSourceManager().isInSystemMacro(Loc))
8382     return;
8383 
8384   PartialDiagnostic PDiag = S.PDiag(diag::warn_printf_data_arg_not_used);
8385   for (auto E : DiagnosticExprs)
8386     PDiag << E->getSourceRange();
8387 
8388   CheckFormatHandler::EmitFormatDiagnostic(
8389                                   S, IsFunctionCall, DiagnosticExprs[0],
8390                                   PDiag, Loc, /*IsStringLocation*/false,
8391                                   DiagnosticExprs[0]->getSourceRange());
8392 }
8393 
8394 bool
8395 CheckFormatHandler::HandleInvalidConversionSpecifier(unsigned argIndex,
8396                                                      SourceLocation Loc,
8397                                                      const char *startSpec,
8398                                                      unsigned specifierLen,
8399                                                      const char *csStart,
8400                                                      unsigned csLen) {
8401   bool keepGoing = true;
8402   if (argIndex < NumDataArgs) {
8403     // Consider the argument coverered, even though the specifier doesn't
8404     // make sense.
8405     CoveredArgs.set(argIndex);
8406   }
8407   else {
8408     // If argIndex exceeds the number of data arguments we
8409     // don't issue a warning because that is just a cascade of warnings (and
8410     // they may have intended '%%' anyway). We don't want to continue processing
8411     // the format string after this point, however, as we will like just get
8412     // gibberish when trying to match arguments.
8413     keepGoing = false;
8414   }
8415 
8416   StringRef Specifier(csStart, csLen);
8417 
8418   // If the specifier in non-printable, it could be the first byte of a UTF-8
8419   // sequence. In that case, print the UTF-8 code point. If not, print the byte
8420   // hex value.
8421   std::string CodePointStr;
8422   if (!llvm::sys::locale::isPrint(*csStart)) {
8423     llvm::UTF32 CodePoint;
8424     const llvm::UTF8 **B = reinterpret_cast<const llvm::UTF8 **>(&csStart);
8425     const llvm::UTF8 *E =
8426         reinterpret_cast<const llvm::UTF8 *>(csStart + csLen);
8427     llvm::ConversionResult Result =
8428         llvm::convertUTF8Sequence(B, E, &CodePoint, llvm::strictConversion);
8429 
8430     if (Result != llvm::conversionOK) {
8431       unsigned char FirstChar = *csStart;
8432       CodePoint = (llvm::UTF32)FirstChar;
8433     }
8434 
8435     llvm::raw_string_ostream OS(CodePointStr);
8436     if (CodePoint < 256)
8437       OS << "\\x" << llvm::format("%02x", CodePoint);
8438     else if (CodePoint <= 0xFFFF)
8439       OS << "\\u" << llvm::format("%04x", CodePoint);
8440     else
8441       OS << "\\U" << llvm::format("%08x", CodePoint);
8442     OS.flush();
8443     Specifier = CodePointStr;
8444   }
8445 
8446   EmitFormatDiagnostic(
8447       S.PDiag(diag::warn_format_invalid_conversion) << Specifier, Loc,
8448       /*IsStringLocation*/ true, getSpecifierRange(startSpec, specifierLen));
8449 
8450   return keepGoing;
8451 }
8452 
8453 void
8454 CheckFormatHandler::HandlePositionalNonpositionalArgs(SourceLocation Loc,
8455                                                       const char *startSpec,
8456                                                       unsigned specifierLen) {
8457   EmitFormatDiagnostic(
8458     S.PDiag(diag::warn_format_mix_positional_nonpositional_args),
8459     Loc, /*isStringLoc*/true, getSpecifierRange(startSpec, specifierLen));
8460 }
8461 
8462 bool
8463 CheckFormatHandler::CheckNumArgs(
8464   const analyze_format_string::FormatSpecifier &FS,
8465   const analyze_format_string::ConversionSpecifier &CS,
8466   const char *startSpecifier, unsigned specifierLen, unsigned argIndex) {
8467 
8468   if (argIndex >= NumDataArgs) {
8469     PartialDiagnostic PDiag = FS.usesPositionalArg()
8470       ? (S.PDiag(diag::warn_printf_positional_arg_exceeds_data_args)
8471            << (argIndex+1) << NumDataArgs)
8472       : S.PDiag(diag::warn_printf_insufficient_data_args);
8473     EmitFormatDiagnostic(
8474       PDiag, getLocationOfByte(CS.getStart()), /*IsStringLocation*/true,
8475       getSpecifierRange(startSpecifier, specifierLen));
8476 
8477     // Since more arguments than conversion tokens are given, by extension
8478     // all arguments are covered, so mark this as so.
8479     UncoveredArg.setAllCovered();
8480     return false;
8481   }
8482   return true;
8483 }
8484 
8485 template<typename Range>
8486 void CheckFormatHandler::EmitFormatDiagnostic(PartialDiagnostic PDiag,
8487                                               SourceLocation Loc,
8488                                               bool IsStringLocation,
8489                                               Range StringRange,
8490                                               ArrayRef<FixItHint> FixIt) {
8491   EmitFormatDiagnostic(S, inFunctionCall, Args[FormatIdx], PDiag,
8492                        Loc, IsStringLocation, StringRange, FixIt);
8493 }
8494 
8495 /// If the format string is not within the function call, emit a note
8496 /// so that the function call and string are in diagnostic messages.
8497 ///
8498 /// \param InFunctionCall if true, the format string is within the function
8499 /// call and only one diagnostic message will be produced.  Otherwise, an
8500 /// extra note will be emitted pointing to location of the format string.
8501 ///
8502 /// \param ArgumentExpr the expression that is passed as the format string
8503 /// argument in the function call.  Used for getting locations when two
8504 /// diagnostics are emitted.
8505 ///
8506 /// \param PDiag the callee should already have provided any strings for the
8507 /// diagnostic message.  This function only adds locations and fixits
8508 /// to diagnostics.
8509 ///
8510 /// \param Loc primary location for diagnostic.  If two diagnostics are
8511 /// required, one will be at Loc and a new SourceLocation will be created for
8512 /// the other one.
8513 ///
8514 /// \param IsStringLocation if true, Loc points to the format string should be
8515 /// used for the note.  Otherwise, Loc points to the argument list and will
8516 /// be used with PDiag.
8517 ///
8518 /// \param StringRange some or all of the string to highlight.  This is
8519 /// templated so it can accept either a CharSourceRange or a SourceRange.
8520 ///
8521 /// \param FixIt optional fix it hint for the format string.
8522 template <typename Range>
8523 void CheckFormatHandler::EmitFormatDiagnostic(
8524     Sema &S, bool InFunctionCall, const Expr *ArgumentExpr,
8525     const PartialDiagnostic &PDiag, SourceLocation Loc, bool IsStringLocation,
8526     Range StringRange, ArrayRef<FixItHint> FixIt) {
8527   if (InFunctionCall) {
8528     const Sema::SemaDiagnosticBuilder &D = S.Diag(Loc, PDiag);
8529     D << StringRange;
8530     D << FixIt;
8531   } else {
8532     S.Diag(IsStringLocation ? ArgumentExpr->getExprLoc() : Loc, PDiag)
8533       << ArgumentExpr->getSourceRange();
8534 
8535     const Sema::SemaDiagnosticBuilder &Note =
8536       S.Diag(IsStringLocation ? Loc : StringRange.getBegin(),
8537              diag::note_format_string_defined);
8538 
8539     Note << StringRange;
8540     Note << FixIt;
8541   }
8542 }
8543 
8544 //===--- CHECK: Printf format string checking ------------------------------===//
8545 
8546 namespace {
8547 
8548 class CheckPrintfHandler : public CheckFormatHandler {
8549 public:
8550   CheckPrintfHandler(Sema &s, const FormatStringLiteral *fexpr,
8551                      const Expr *origFormatExpr,
8552                      const Sema::FormatStringType type, unsigned firstDataArg,
8553                      unsigned numDataArgs, bool isObjC, const char *beg,
8554                      bool hasVAListArg, ArrayRef<const Expr *> Args,
8555                      unsigned formatIdx, bool inFunctionCall,
8556                      Sema::VariadicCallType CallType,
8557                      llvm::SmallBitVector &CheckedVarArgs,
8558                      UncoveredArgHandler &UncoveredArg)
8559       : CheckFormatHandler(s, fexpr, origFormatExpr, type, firstDataArg,
8560                            numDataArgs, beg, hasVAListArg, Args, formatIdx,
8561                            inFunctionCall, CallType, CheckedVarArgs,
8562                            UncoveredArg) {}
8563 
8564   bool isObjCContext() const { return FSType == Sema::FST_NSString; }
8565 
8566   /// Returns true if '%@' specifiers are allowed in the format string.
8567   bool allowsObjCArg() const {
8568     return FSType == Sema::FST_NSString || FSType == Sema::FST_OSLog ||
8569            FSType == Sema::FST_OSTrace;
8570   }
8571 
8572   bool HandleInvalidPrintfConversionSpecifier(
8573                                       const analyze_printf::PrintfSpecifier &FS,
8574                                       const char *startSpecifier,
8575                                       unsigned specifierLen) override;
8576 
8577   void handleInvalidMaskType(StringRef MaskType) override;
8578 
8579   bool HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier &FS,
8580                              const char *startSpecifier,
8581                              unsigned specifierLen) override;
8582   bool checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
8583                        const char *StartSpecifier,
8584                        unsigned SpecifierLen,
8585                        const Expr *E);
8586 
8587   bool HandleAmount(const analyze_format_string::OptionalAmount &Amt, unsigned k,
8588                     const char *startSpecifier, unsigned specifierLen);
8589   void HandleInvalidAmount(const analyze_printf::PrintfSpecifier &FS,
8590                            const analyze_printf::OptionalAmount &Amt,
8591                            unsigned type,
8592                            const char *startSpecifier, unsigned specifierLen);
8593   void HandleFlag(const analyze_printf::PrintfSpecifier &FS,
8594                   const analyze_printf::OptionalFlag &flag,
8595                   const char *startSpecifier, unsigned specifierLen);
8596   void HandleIgnoredFlag(const analyze_printf::PrintfSpecifier &FS,
8597                          const analyze_printf::OptionalFlag &ignoredFlag,
8598                          const analyze_printf::OptionalFlag &flag,
8599                          const char *startSpecifier, unsigned specifierLen);
8600   bool checkForCStrMembers(const analyze_printf::ArgType &AT,
8601                            const Expr *E);
8602 
8603   void HandleEmptyObjCModifierFlag(const char *startFlag,
8604                                    unsigned flagLen) override;
8605 
8606   void HandleInvalidObjCModifierFlag(const char *startFlag,
8607                                             unsigned flagLen) override;
8608 
8609   void HandleObjCFlagsWithNonObjCConversion(const char *flagsStart,
8610                                            const char *flagsEnd,
8611                                            const char *conversionPosition)
8612                                              override;
8613 };
8614 
8615 } // namespace
8616 
8617 bool CheckPrintfHandler::HandleInvalidPrintfConversionSpecifier(
8618                                       const analyze_printf::PrintfSpecifier &FS,
8619                                       const char *startSpecifier,
8620                                       unsigned specifierLen) {
8621   const analyze_printf::PrintfConversionSpecifier &CS =
8622     FS.getConversionSpecifier();
8623 
8624   return HandleInvalidConversionSpecifier(FS.getArgIndex(),
8625                                           getLocationOfByte(CS.getStart()),
8626                                           startSpecifier, specifierLen,
8627                                           CS.getStart(), CS.getLength());
8628 }
8629 
8630 void CheckPrintfHandler::handleInvalidMaskType(StringRef MaskType) {
8631   S.Diag(getLocationOfByte(MaskType.data()), diag::err_invalid_mask_type_size);
8632 }
8633 
8634 bool CheckPrintfHandler::HandleAmount(
8635                                const analyze_format_string::OptionalAmount &Amt,
8636                                unsigned k, const char *startSpecifier,
8637                                unsigned specifierLen) {
8638   if (Amt.hasDataArgument()) {
8639     if (!HasVAListArg) {
8640       unsigned argIndex = Amt.getArgIndex();
8641       if (argIndex >= NumDataArgs) {
8642         EmitFormatDiagnostic(S.PDiag(diag::warn_printf_asterisk_missing_arg)
8643                                << k,
8644                              getLocationOfByte(Amt.getStart()),
8645                              /*IsStringLocation*/true,
8646                              getSpecifierRange(startSpecifier, specifierLen));
8647         // Don't do any more checking.  We will just emit
8648         // spurious errors.
8649         return false;
8650       }
8651 
8652       // Type check the data argument.  It should be an 'int'.
8653       // Although not in conformance with C99, we also allow the argument to be
8654       // an 'unsigned int' as that is a reasonably safe case.  GCC also
8655       // doesn't emit a warning for that case.
8656       CoveredArgs.set(argIndex);
8657       const Expr *Arg = getDataArg(argIndex);
8658       if (!Arg)
8659         return false;
8660 
8661       QualType T = Arg->getType();
8662 
8663       const analyze_printf::ArgType &AT = Amt.getArgType(S.Context);
8664       assert(AT.isValid());
8665 
8666       if (!AT.matchesType(S.Context, T)) {
8667         EmitFormatDiagnostic(S.PDiag(diag::warn_printf_asterisk_wrong_type)
8668                                << k << AT.getRepresentativeTypeName(S.Context)
8669                                << T << Arg->getSourceRange(),
8670                              getLocationOfByte(Amt.getStart()),
8671                              /*IsStringLocation*/true,
8672                              getSpecifierRange(startSpecifier, specifierLen));
8673         // Don't do any more checking.  We will just emit
8674         // spurious errors.
8675         return false;
8676       }
8677     }
8678   }
8679   return true;
8680 }
8681 
8682 void CheckPrintfHandler::HandleInvalidAmount(
8683                                       const analyze_printf::PrintfSpecifier &FS,
8684                                       const analyze_printf::OptionalAmount &Amt,
8685                                       unsigned type,
8686                                       const char *startSpecifier,
8687                                       unsigned specifierLen) {
8688   const analyze_printf::PrintfConversionSpecifier &CS =
8689     FS.getConversionSpecifier();
8690 
8691   FixItHint fixit =
8692     Amt.getHowSpecified() == analyze_printf::OptionalAmount::Constant
8693       ? FixItHint::CreateRemoval(getSpecifierRange(Amt.getStart(),
8694                                  Amt.getConstantLength()))
8695       : FixItHint();
8696 
8697   EmitFormatDiagnostic(S.PDiag(diag::warn_printf_nonsensical_optional_amount)
8698                          << type << CS.toString(),
8699                        getLocationOfByte(Amt.getStart()),
8700                        /*IsStringLocation*/true,
8701                        getSpecifierRange(startSpecifier, specifierLen),
8702                        fixit);
8703 }
8704 
8705 void CheckPrintfHandler::HandleFlag(const analyze_printf::PrintfSpecifier &FS,
8706                                     const analyze_printf::OptionalFlag &flag,
8707                                     const char *startSpecifier,
8708                                     unsigned specifierLen) {
8709   // Warn about pointless flag with a fixit removal.
8710   const analyze_printf::PrintfConversionSpecifier &CS =
8711     FS.getConversionSpecifier();
8712   EmitFormatDiagnostic(S.PDiag(diag::warn_printf_nonsensical_flag)
8713                          << flag.toString() << CS.toString(),
8714                        getLocationOfByte(flag.getPosition()),
8715                        /*IsStringLocation*/true,
8716                        getSpecifierRange(startSpecifier, specifierLen),
8717                        FixItHint::CreateRemoval(
8718                          getSpecifierRange(flag.getPosition(), 1)));
8719 }
8720 
8721 void CheckPrintfHandler::HandleIgnoredFlag(
8722                                 const analyze_printf::PrintfSpecifier &FS,
8723                                 const analyze_printf::OptionalFlag &ignoredFlag,
8724                                 const analyze_printf::OptionalFlag &flag,
8725                                 const char *startSpecifier,
8726                                 unsigned specifierLen) {
8727   // Warn about ignored flag with a fixit removal.
8728   EmitFormatDiagnostic(S.PDiag(diag::warn_printf_ignored_flag)
8729                          << ignoredFlag.toString() << flag.toString(),
8730                        getLocationOfByte(ignoredFlag.getPosition()),
8731                        /*IsStringLocation*/true,
8732                        getSpecifierRange(startSpecifier, specifierLen),
8733                        FixItHint::CreateRemoval(
8734                          getSpecifierRange(ignoredFlag.getPosition(), 1)));
8735 }
8736 
8737 void CheckPrintfHandler::HandleEmptyObjCModifierFlag(const char *startFlag,
8738                                                      unsigned flagLen) {
8739   // Warn about an empty flag.
8740   EmitFormatDiagnostic(S.PDiag(diag::warn_printf_empty_objc_flag),
8741                        getLocationOfByte(startFlag),
8742                        /*IsStringLocation*/true,
8743                        getSpecifierRange(startFlag, flagLen));
8744 }
8745 
8746 void CheckPrintfHandler::HandleInvalidObjCModifierFlag(const char *startFlag,
8747                                                        unsigned flagLen) {
8748   // Warn about an invalid flag.
8749   auto Range = getSpecifierRange(startFlag, flagLen);
8750   StringRef flag(startFlag, flagLen);
8751   EmitFormatDiagnostic(S.PDiag(diag::warn_printf_invalid_objc_flag) << flag,
8752                       getLocationOfByte(startFlag),
8753                       /*IsStringLocation*/true,
8754                       Range, FixItHint::CreateRemoval(Range));
8755 }
8756 
8757 void CheckPrintfHandler::HandleObjCFlagsWithNonObjCConversion(
8758     const char *flagsStart, const char *flagsEnd, const char *conversionPosition) {
8759     // Warn about using '[...]' without a '@' conversion.
8760     auto Range = getSpecifierRange(flagsStart, flagsEnd - flagsStart + 1);
8761     auto diag = diag::warn_printf_ObjCflags_without_ObjCConversion;
8762     EmitFormatDiagnostic(S.PDiag(diag) << StringRef(conversionPosition, 1),
8763                          getLocationOfByte(conversionPosition),
8764                          /*IsStringLocation*/true,
8765                          Range, FixItHint::CreateRemoval(Range));
8766 }
8767 
8768 // Determines if the specified is a C++ class or struct containing
8769 // a member with the specified name and kind (e.g. a CXXMethodDecl named
8770 // "c_str()").
8771 template<typename MemberKind>
8772 static llvm::SmallPtrSet<MemberKind*, 1>
8773 CXXRecordMembersNamed(StringRef Name, Sema &S, QualType Ty) {
8774   const RecordType *RT = Ty->getAs<RecordType>();
8775   llvm::SmallPtrSet<MemberKind*, 1> Results;
8776 
8777   if (!RT)
8778     return Results;
8779   const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
8780   if (!RD || !RD->getDefinition())
8781     return Results;
8782 
8783   LookupResult R(S, &S.Context.Idents.get(Name), SourceLocation(),
8784                  Sema::LookupMemberName);
8785   R.suppressDiagnostics();
8786 
8787   // We just need to include all members of the right kind turned up by the
8788   // filter, at this point.
8789   if (S.LookupQualifiedName(R, RT->getDecl()))
8790     for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
8791       NamedDecl *decl = (*I)->getUnderlyingDecl();
8792       if (MemberKind *FK = dyn_cast<MemberKind>(decl))
8793         Results.insert(FK);
8794     }
8795   return Results;
8796 }
8797 
8798 /// Check if we could call '.c_str()' on an object.
8799 ///
8800 /// FIXME: This returns the wrong results in some cases (if cv-qualifiers don't
8801 /// allow the call, or if it would be ambiguous).
8802 bool Sema::hasCStrMethod(const Expr *E) {
8803   using MethodSet = llvm::SmallPtrSet<CXXMethodDecl *, 1>;
8804 
8805   MethodSet Results =
8806       CXXRecordMembersNamed<CXXMethodDecl>("c_str", *this, E->getType());
8807   for (MethodSet::iterator MI = Results.begin(), ME = Results.end();
8808        MI != ME; ++MI)
8809     if ((*MI)->getMinRequiredArguments() == 0)
8810       return true;
8811   return false;
8812 }
8813 
8814 // Check if a (w)string was passed when a (w)char* was needed, and offer a
8815 // better diagnostic if so. AT is assumed to be valid.
8816 // Returns true when a c_str() conversion method is found.
8817 bool CheckPrintfHandler::checkForCStrMembers(
8818     const analyze_printf::ArgType &AT, const Expr *E) {
8819   using MethodSet = llvm::SmallPtrSet<CXXMethodDecl *, 1>;
8820 
8821   MethodSet Results =
8822       CXXRecordMembersNamed<CXXMethodDecl>("c_str", S, E->getType());
8823 
8824   for (MethodSet::iterator MI = Results.begin(), ME = Results.end();
8825        MI != ME; ++MI) {
8826     const CXXMethodDecl *Method = *MI;
8827     if (Method->getMinRequiredArguments() == 0 &&
8828         AT.matchesType(S.Context, Method->getReturnType())) {
8829       // FIXME: Suggest parens if the expression needs them.
8830       SourceLocation EndLoc = S.getLocForEndOfToken(E->getEndLoc());
8831       S.Diag(E->getBeginLoc(), diag::note_printf_c_str)
8832           << "c_str()" << FixItHint::CreateInsertion(EndLoc, ".c_str()");
8833       return true;
8834     }
8835   }
8836 
8837   return false;
8838 }
8839 
8840 bool
8841 CheckPrintfHandler::HandlePrintfSpecifier(const analyze_printf::PrintfSpecifier
8842                                             &FS,
8843                                           const char *startSpecifier,
8844                                           unsigned specifierLen) {
8845   using namespace analyze_format_string;
8846   using namespace analyze_printf;
8847 
8848   const PrintfConversionSpecifier &CS = FS.getConversionSpecifier();
8849 
8850   if (FS.consumesDataArgument()) {
8851     if (atFirstArg) {
8852         atFirstArg = false;
8853         usesPositionalArgs = FS.usesPositionalArg();
8854     }
8855     else if (usesPositionalArgs != FS.usesPositionalArg()) {
8856       HandlePositionalNonpositionalArgs(getLocationOfByte(CS.getStart()),
8857                                         startSpecifier, specifierLen);
8858       return false;
8859     }
8860   }
8861 
8862   // First check if the field width, precision, and conversion specifier
8863   // have matching data arguments.
8864   if (!HandleAmount(FS.getFieldWidth(), /* field width */ 0,
8865                     startSpecifier, specifierLen)) {
8866     return false;
8867   }
8868 
8869   if (!HandleAmount(FS.getPrecision(), /* precision */ 1,
8870                     startSpecifier, specifierLen)) {
8871     return false;
8872   }
8873 
8874   if (!CS.consumesDataArgument()) {
8875     // FIXME: Technically specifying a precision or field width here
8876     // makes no sense.  Worth issuing a warning at some point.
8877     return true;
8878   }
8879 
8880   // Consume the argument.
8881   unsigned argIndex = FS.getArgIndex();
8882   if (argIndex < NumDataArgs) {
8883     // The check to see if the argIndex is valid will come later.
8884     // We set the bit here because we may exit early from this
8885     // function if we encounter some other error.
8886     CoveredArgs.set(argIndex);
8887   }
8888 
8889   // FreeBSD kernel extensions.
8890   if (CS.getKind() == ConversionSpecifier::FreeBSDbArg ||
8891       CS.getKind() == ConversionSpecifier::FreeBSDDArg) {
8892     // We need at least two arguments.
8893     if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex + 1))
8894       return false;
8895 
8896     // Claim the second argument.
8897     CoveredArgs.set(argIndex + 1);
8898 
8899     // Type check the first argument (int for %b, pointer for %D)
8900     const Expr *Ex = getDataArg(argIndex);
8901     const analyze_printf::ArgType &AT =
8902       (CS.getKind() == ConversionSpecifier::FreeBSDbArg) ?
8903         ArgType(S.Context.IntTy) : ArgType::CPointerTy;
8904     if (AT.isValid() && !AT.matchesType(S.Context, Ex->getType()))
8905       EmitFormatDiagnostic(
8906           S.PDiag(diag::warn_format_conversion_argument_type_mismatch)
8907               << AT.getRepresentativeTypeName(S.Context) << Ex->getType()
8908               << false << Ex->getSourceRange(),
8909           Ex->getBeginLoc(), /*IsStringLocation*/ false,
8910           getSpecifierRange(startSpecifier, specifierLen));
8911 
8912     // Type check the second argument (char * for both %b and %D)
8913     Ex = getDataArg(argIndex + 1);
8914     const analyze_printf::ArgType &AT2 = ArgType::CStrTy;
8915     if (AT2.isValid() && !AT2.matchesType(S.Context, Ex->getType()))
8916       EmitFormatDiagnostic(
8917           S.PDiag(diag::warn_format_conversion_argument_type_mismatch)
8918               << AT2.getRepresentativeTypeName(S.Context) << Ex->getType()
8919               << false << Ex->getSourceRange(),
8920           Ex->getBeginLoc(), /*IsStringLocation*/ false,
8921           getSpecifierRange(startSpecifier, specifierLen));
8922 
8923      return true;
8924   }
8925 
8926   // Check for using an Objective-C specific conversion specifier
8927   // in a non-ObjC literal.
8928   if (!allowsObjCArg() && CS.isObjCArg()) {
8929     return HandleInvalidPrintfConversionSpecifier(FS, startSpecifier,
8930                                                   specifierLen);
8931   }
8932 
8933   // %P can only be used with os_log.
8934   if (FSType != Sema::FST_OSLog && CS.getKind() == ConversionSpecifier::PArg) {
8935     return HandleInvalidPrintfConversionSpecifier(FS, startSpecifier,
8936                                                   specifierLen);
8937   }
8938 
8939   // %n is not allowed with os_log.
8940   if (FSType == Sema::FST_OSLog && CS.getKind() == ConversionSpecifier::nArg) {
8941     EmitFormatDiagnostic(S.PDiag(diag::warn_os_log_format_narg),
8942                          getLocationOfByte(CS.getStart()),
8943                          /*IsStringLocation*/ false,
8944                          getSpecifierRange(startSpecifier, specifierLen));
8945 
8946     return true;
8947   }
8948 
8949   // Only scalars are allowed for os_trace.
8950   if (FSType == Sema::FST_OSTrace &&
8951       (CS.getKind() == ConversionSpecifier::PArg ||
8952        CS.getKind() == ConversionSpecifier::sArg ||
8953        CS.getKind() == ConversionSpecifier::ObjCObjArg)) {
8954     return HandleInvalidPrintfConversionSpecifier(FS, startSpecifier,
8955                                                   specifierLen);
8956   }
8957 
8958   // Check for use of public/private annotation outside of os_log().
8959   if (FSType != Sema::FST_OSLog) {
8960     if (FS.isPublic().isSet()) {
8961       EmitFormatDiagnostic(S.PDiag(diag::warn_format_invalid_annotation)
8962                                << "public",
8963                            getLocationOfByte(FS.isPublic().getPosition()),
8964                            /*IsStringLocation*/ false,
8965                            getSpecifierRange(startSpecifier, specifierLen));
8966     }
8967     if (FS.isPrivate().isSet()) {
8968       EmitFormatDiagnostic(S.PDiag(diag::warn_format_invalid_annotation)
8969                                << "private",
8970                            getLocationOfByte(FS.isPrivate().getPosition()),
8971                            /*IsStringLocation*/ false,
8972                            getSpecifierRange(startSpecifier, specifierLen));
8973     }
8974   }
8975 
8976   // Check for invalid use of field width
8977   if (!FS.hasValidFieldWidth()) {
8978     HandleInvalidAmount(FS, FS.getFieldWidth(), /* field width */ 0,
8979         startSpecifier, specifierLen);
8980   }
8981 
8982   // Check for invalid use of precision
8983   if (!FS.hasValidPrecision()) {
8984     HandleInvalidAmount(FS, FS.getPrecision(), /* precision */ 1,
8985         startSpecifier, specifierLen);
8986   }
8987 
8988   // Precision is mandatory for %P specifier.
8989   if (CS.getKind() == ConversionSpecifier::PArg &&
8990       FS.getPrecision().getHowSpecified() == OptionalAmount::NotSpecified) {
8991     EmitFormatDiagnostic(S.PDiag(diag::warn_format_P_no_precision),
8992                          getLocationOfByte(startSpecifier),
8993                          /*IsStringLocation*/ false,
8994                          getSpecifierRange(startSpecifier, specifierLen));
8995   }
8996 
8997   // Check each flag does not conflict with any other component.
8998   if (!FS.hasValidThousandsGroupingPrefix())
8999     HandleFlag(FS, FS.hasThousandsGrouping(), startSpecifier, specifierLen);
9000   if (!FS.hasValidLeadingZeros())
9001     HandleFlag(FS, FS.hasLeadingZeros(), startSpecifier, specifierLen);
9002   if (!FS.hasValidPlusPrefix())
9003     HandleFlag(FS, FS.hasPlusPrefix(), startSpecifier, specifierLen);
9004   if (!FS.hasValidSpacePrefix())
9005     HandleFlag(FS, FS.hasSpacePrefix(), startSpecifier, specifierLen);
9006   if (!FS.hasValidAlternativeForm())
9007     HandleFlag(FS, FS.hasAlternativeForm(), startSpecifier, specifierLen);
9008   if (!FS.hasValidLeftJustified())
9009     HandleFlag(FS, FS.isLeftJustified(), startSpecifier, specifierLen);
9010 
9011   // Check that flags are not ignored by another flag
9012   if (FS.hasSpacePrefix() && FS.hasPlusPrefix()) // ' ' ignored by '+'
9013     HandleIgnoredFlag(FS, FS.hasSpacePrefix(), FS.hasPlusPrefix(),
9014         startSpecifier, specifierLen);
9015   if (FS.hasLeadingZeros() && FS.isLeftJustified()) // '0' ignored by '-'
9016     HandleIgnoredFlag(FS, FS.hasLeadingZeros(), FS.isLeftJustified(),
9017             startSpecifier, specifierLen);
9018 
9019   // Check the length modifier is valid with the given conversion specifier.
9020   if (!FS.hasValidLengthModifier(S.getASTContext().getTargetInfo(),
9021                                  S.getLangOpts()))
9022     HandleInvalidLengthModifier(FS, CS, startSpecifier, specifierLen,
9023                                 diag::warn_format_nonsensical_length);
9024   else if (!FS.hasStandardLengthModifier())
9025     HandleNonStandardLengthModifier(FS, startSpecifier, specifierLen);
9026   else if (!FS.hasStandardLengthConversionCombination())
9027     HandleInvalidLengthModifier(FS, CS, startSpecifier, specifierLen,
9028                                 diag::warn_format_non_standard_conversion_spec);
9029 
9030   if (!FS.hasStandardConversionSpecifier(S.getLangOpts()))
9031     HandleNonStandardConversionSpecifier(CS, startSpecifier, specifierLen);
9032 
9033   // The remaining checks depend on the data arguments.
9034   if (HasVAListArg)
9035     return true;
9036 
9037   if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex))
9038     return false;
9039 
9040   const Expr *Arg = getDataArg(argIndex);
9041   if (!Arg)
9042     return true;
9043 
9044   return checkFormatExpr(FS, startSpecifier, specifierLen, Arg);
9045 }
9046 
9047 static bool requiresParensToAddCast(const Expr *E) {
9048   // FIXME: We should have a general way to reason about operator
9049   // precedence and whether parens are actually needed here.
9050   // Take care of a few common cases where they aren't.
9051   const Expr *Inside = E->IgnoreImpCasts();
9052   if (const PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(Inside))
9053     Inside = POE->getSyntacticForm()->IgnoreImpCasts();
9054 
9055   switch (Inside->getStmtClass()) {
9056   case Stmt::ArraySubscriptExprClass:
9057   case Stmt::CallExprClass:
9058   case Stmt::CharacterLiteralClass:
9059   case Stmt::CXXBoolLiteralExprClass:
9060   case Stmt::DeclRefExprClass:
9061   case Stmt::FloatingLiteralClass:
9062   case Stmt::IntegerLiteralClass:
9063   case Stmt::MemberExprClass:
9064   case Stmt::ObjCArrayLiteralClass:
9065   case Stmt::ObjCBoolLiteralExprClass:
9066   case Stmt::ObjCBoxedExprClass:
9067   case Stmt::ObjCDictionaryLiteralClass:
9068   case Stmt::ObjCEncodeExprClass:
9069   case Stmt::ObjCIvarRefExprClass:
9070   case Stmt::ObjCMessageExprClass:
9071   case Stmt::ObjCPropertyRefExprClass:
9072   case Stmt::ObjCStringLiteralClass:
9073   case Stmt::ObjCSubscriptRefExprClass:
9074   case Stmt::ParenExprClass:
9075   case Stmt::StringLiteralClass:
9076   case Stmt::UnaryOperatorClass:
9077     return false;
9078   default:
9079     return true;
9080   }
9081 }
9082 
9083 static std::pair<QualType, StringRef>
9084 shouldNotPrintDirectly(const ASTContext &Context,
9085                        QualType IntendedTy,
9086                        const Expr *E) {
9087   // Use a 'while' to peel off layers of typedefs.
9088   QualType TyTy = IntendedTy;
9089   while (const TypedefType *UserTy = TyTy->getAs<TypedefType>()) {
9090     StringRef Name = UserTy->getDecl()->getName();
9091     QualType CastTy = llvm::StringSwitch<QualType>(Name)
9092       .Case("CFIndex", Context.getNSIntegerType())
9093       .Case("NSInteger", Context.getNSIntegerType())
9094       .Case("NSUInteger", Context.getNSUIntegerType())
9095       .Case("SInt32", Context.IntTy)
9096       .Case("UInt32", Context.UnsignedIntTy)
9097       .Default(QualType());
9098 
9099     if (!CastTy.isNull())
9100       return std::make_pair(CastTy, Name);
9101 
9102     TyTy = UserTy->desugar();
9103   }
9104 
9105   // Strip parens if necessary.
9106   if (const ParenExpr *PE = dyn_cast<ParenExpr>(E))
9107     return shouldNotPrintDirectly(Context,
9108                                   PE->getSubExpr()->getType(),
9109                                   PE->getSubExpr());
9110 
9111   // If this is a conditional expression, then its result type is constructed
9112   // via usual arithmetic conversions and thus there might be no necessary
9113   // typedef sugar there.  Recurse to operands to check for NSInteger &
9114   // Co. usage condition.
9115   if (const ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
9116     QualType TrueTy, FalseTy;
9117     StringRef TrueName, FalseName;
9118 
9119     std::tie(TrueTy, TrueName) =
9120       shouldNotPrintDirectly(Context,
9121                              CO->getTrueExpr()->getType(),
9122                              CO->getTrueExpr());
9123     std::tie(FalseTy, FalseName) =
9124       shouldNotPrintDirectly(Context,
9125                              CO->getFalseExpr()->getType(),
9126                              CO->getFalseExpr());
9127 
9128     if (TrueTy == FalseTy)
9129       return std::make_pair(TrueTy, TrueName);
9130     else if (TrueTy.isNull())
9131       return std::make_pair(FalseTy, FalseName);
9132     else if (FalseTy.isNull())
9133       return std::make_pair(TrueTy, TrueName);
9134   }
9135 
9136   return std::make_pair(QualType(), StringRef());
9137 }
9138 
9139 /// Return true if \p ICE is an implicit argument promotion of an arithmetic
9140 /// type. Bit-field 'promotions' from a higher ranked type to a lower ranked
9141 /// type do not count.
9142 static bool
9143 isArithmeticArgumentPromotion(Sema &S, const ImplicitCastExpr *ICE) {
9144   QualType From = ICE->getSubExpr()->getType();
9145   QualType To = ICE->getType();
9146   // It's an integer promotion if the destination type is the promoted
9147   // source type.
9148   if (ICE->getCastKind() == CK_IntegralCast &&
9149       From->isPromotableIntegerType() &&
9150       S.Context.getPromotedIntegerType(From) == To)
9151     return true;
9152   // Look through vector types, since we do default argument promotion for
9153   // those in OpenCL.
9154   if (const auto *VecTy = From->getAs<ExtVectorType>())
9155     From = VecTy->getElementType();
9156   if (const auto *VecTy = To->getAs<ExtVectorType>())
9157     To = VecTy->getElementType();
9158   // It's a floating promotion if the source type is a lower rank.
9159   return ICE->getCastKind() == CK_FloatingCast &&
9160          S.Context.getFloatingTypeOrder(From, To) < 0;
9161 }
9162 
9163 bool
9164 CheckPrintfHandler::checkFormatExpr(const analyze_printf::PrintfSpecifier &FS,
9165                                     const char *StartSpecifier,
9166                                     unsigned SpecifierLen,
9167                                     const Expr *E) {
9168   using namespace analyze_format_string;
9169   using namespace analyze_printf;
9170 
9171   // Now type check the data expression that matches the
9172   // format specifier.
9173   const analyze_printf::ArgType &AT = FS.getArgType(S.Context, isObjCContext());
9174   if (!AT.isValid())
9175     return true;
9176 
9177   QualType ExprTy = E->getType();
9178   while (const TypeOfExprType *TET = dyn_cast<TypeOfExprType>(ExprTy)) {
9179     ExprTy = TET->getUnderlyingExpr()->getType();
9180   }
9181 
9182   // Diagnose attempts to print a boolean value as a character. Unlike other
9183   // -Wformat diagnostics, this is fine from a type perspective, but it still
9184   // doesn't make sense.
9185   if (FS.getConversionSpecifier().getKind() == ConversionSpecifier::cArg &&
9186       E->isKnownToHaveBooleanValue()) {
9187     const CharSourceRange &CSR =
9188         getSpecifierRange(StartSpecifier, SpecifierLen);
9189     SmallString<4> FSString;
9190     llvm::raw_svector_ostream os(FSString);
9191     FS.toString(os);
9192     EmitFormatDiagnostic(S.PDiag(diag::warn_format_bool_as_character)
9193                              << FSString,
9194                          E->getExprLoc(), false, CSR);
9195     return true;
9196   }
9197 
9198   analyze_printf::ArgType::MatchKind Match = AT.matchesType(S.Context, ExprTy);
9199   if (Match == analyze_printf::ArgType::Match)
9200     return true;
9201 
9202   // Look through argument promotions for our error message's reported type.
9203   // This includes the integral and floating promotions, but excludes array
9204   // and function pointer decay (seeing that an argument intended to be a
9205   // string has type 'char [6]' is probably more confusing than 'char *') and
9206   // certain bitfield promotions (bitfields can be 'demoted' to a lesser type).
9207   if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
9208     if (isArithmeticArgumentPromotion(S, ICE)) {
9209       E = ICE->getSubExpr();
9210       ExprTy = E->getType();
9211 
9212       // Check if we didn't match because of an implicit cast from a 'char'
9213       // or 'short' to an 'int'.  This is done because printf is a varargs
9214       // function.
9215       if (ICE->getType() == S.Context.IntTy ||
9216           ICE->getType() == S.Context.UnsignedIntTy) {
9217         // All further checking is done on the subexpression
9218         const analyze_printf::ArgType::MatchKind ImplicitMatch =
9219             AT.matchesType(S.Context, ExprTy);
9220         if (ImplicitMatch == analyze_printf::ArgType::Match)
9221           return true;
9222         if (ImplicitMatch == ArgType::NoMatchPedantic ||
9223             ImplicitMatch == ArgType::NoMatchTypeConfusion)
9224           Match = ImplicitMatch;
9225       }
9226     }
9227   } else if (const CharacterLiteral *CL = dyn_cast<CharacterLiteral>(E)) {
9228     // Special case for 'a', which has type 'int' in C.
9229     // Note, however, that we do /not/ want to treat multibyte constants like
9230     // 'MooV' as characters! This form is deprecated but still exists. In
9231     // addition, don't treat expressions as of type 'char' if one byte length
9232     // modifier is provided.
9233     if (ExprTy == S.Context.IntTy &&
9234         FS.getLengthModifier().getKind() != LengthModifier::AsChar)
9235       if (llvm::isUIntN(S.Context.getCharWidth(), CL->getValue()))
9236         ExprTy = S.Context.CharTy;
9237   }
9238 
9239   // Look through enums to their underlying type.
9240   bool IsEnum = false;
9241   if (auto EnumTy = ExprTy->getAs<EnumType>()) {
9242     ExprTy = EnumTy->getDecl()->getIntegerType();
9243     IsEnum = true;
9244   }
9245 
9246   // %C in an Objective-C context prints a unichar, not a wchar_t.
9247   // If the argument is an integer of some kind, believe the %C and suggest
9248   // a cast instead of changing the conversion specifier.
9249   QualType IntendedTy = ExprTy;
9250   if (isObjCContext() &&
9251       FS.getConversionSpecifier().getKind() == ConversionSpecifier::CArg) {
9252     if (ExprTy->isIntegralOrUnscopedEnumerationType() &&
9253         !ExprTy->isCharType()) {
9254       // 'unichar' is defined as a typedef of unsigned short, but we should
9255       // prefer using the typedef if it is visible.
9256       IntendedTy = S.Context.UnsignedShortTy;
9257 
9258       // While we are here, check if the value is an IntegerLiteral that happens
9259       // to be within the valid range.
9260       if (const IntegerLiteral *IL = dyn_cast<IntegerLiteral>(E)) {
9261         const llvm::APInt &V = IL->getValue();
9262         if (V.getActiveBits() <= S.Context.getTypeSize(IntendedTy))
9263           return true;
9264       }
9265 
9266       LookupResult Result(S, &S.Context.Idents.get("unichar"), E->getBeginLoc(),
9267                           Sema::LookupOrdinaryName);
9268       if (S.LookupName(Result, S.getCurScope())) {
9269         NamedDecl *ND = Result.getFoundDecl();
9270         if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(ND))
9271           if (TD->getUnderlyingType() == IntendedTy)
9272             IntendedTy = S.Context.getTypedefType(TD);
9273       }
9274     }
9275   }
9276 
9277   // Special-case some of Darwin's platform-independence types by suggesting
9278   // casts to primitive types that are known to be large enough.
9279   bool ShouldNotPrintDirectly = false; StringRef CastTyName;
9280   if (S.Context.getTargetInfo().getTriple().isOSDarwin()) {
9281     QualType CastTy;
9282     std::tie(CastTy, CastTyName) = shouldNotPrintDirectly(S.Context, IntendedTy, E);
9283     if (!CastTy.isNull()) {
9284       // %zi/%zu and %td/%tu are OK to use for NSInteger/NSUInteger of type int
9285       // (long in ASTContext). Only complain to pedants.
9286       if ((CastTyName == "NSInteger" || CastTyName == "NSUInteger") &&
9287           (AT.isSizeT() || AT.isPtrdiffT()) &&
9288           AT.matchesType(S.Context, CastTy))
9289         Match = ArgType::NoMatchPedantic;
9290       IntendedTy = CastTy;
9291       ShouldNotPrintDirectly = true;
9292     }
9293   }
9294 
9295   // We may be able to offer a FixItHint if it is a supported type.
9296   PrintfSpecifier fixedFS = FS;
9297   bool Success =
9298       fixedFS.fixType(IntendedTy, S.getLangOpts(), S.Context, isObjCContext());
9299 
9300   if (Success) {
9301     // Get the fix string from the fixed format specifier
9302     SmallString<16> buf;
9303     llvm::raw_svector_ostream os(buf);
9304     fixedFS.toString(os);
9305 
9306     CharSourceRange SpecRange = getSpecifierRange(StartSpecifier, SpecifierLen);
9307 
9308     if (IntendedTy == ExprTy && !ShouldNotPrintDirectly) {
9309       unsigned Diag;
9310       switch (Match) {
9311       case ArgType::Match: llvm_unreachable("expected non-matching");
9312       case ArgType::NoMatchPedantic:
9313         Diag = diag::warn_format_conversion_argument_type_mismatch_pedantic;
9314         break;
9315       case ArgType::NoMatchTypeConfusion:
9316         Diag = diag::warn_format_conversion_argument_type_mismatch_confusion;
9317         break;
9318       case ArgType::NoMatch:
9319         Diag = diag::warn_format_conversion_argument_type_mismatch;
9320         break;
9321       }
9322 
9323       // In this case, the specifier is wrong and should be changed to match
9324       // the argument.
9325       EmitFormatDiagnostic(S.PDiag(Diag)
9326                                << AT.getRepresentativeTypeName(S.Context)
9327                                << IntendedTy << IsEnum << E->getSourceRange(),
9328                            E->getBeginLoc(),
9329                            /*IsStringLocation*/ false, SpecRange,
9330                            FixItHint::CreateReplacement(SpecRange, os.str()));
9331     } else {
9332       // The canonical type for formatting this value is different from the
9333       // actual type of the expression. (This occurs, for example, with Darwin's
9334       // NSInteger on 32-bit platforms, where it is typedef'd as 'int', but
9335       // should be printed as 'long' for 64-bit compatibility.)
9336       // Rather than emitting a normal format/argument mismatch, we want to
9337       // add a cast to the recommended type (and correct the format string
9338       // if necessary).
9339       SmallString<16> CastBuf;
9340       llvm::raw_svector_ostream CastFix(CastBuf);
9341       CastFix << "(";
9342       IntendedTy.print(CastFix, S.Context.getPrintingPolicy());
9343       CastFix << ")";
9344 
9345       SmallVector<FixItHint,4> Hints;
9346       if (!AT.matchesType(S.Context, IntendedTy) || ShouldNotPrintDirectly)
9347         Hints.push_back(FixItHint::CreateReplacement(SpecRange, os.str()));
9348 
9349       if (const CStyleCastExpr *CCast = dyn_cast<CStyleCastExpr>(E)) {
9350         // If there's already a cast present, just replace it.
9351         SourceRange CastRange(CCast->getLParenLoc(), CCast->getRParenLoc());
9352         Hints.push_back(FixItHint::CreateReplacement(CastRange, CastFix.str()));
9353 
9354       } else if (!requiresParensToAddCast(E)) {
9355         // If the expression has high enough precedence,
9356         // just write the C-style cast.
9357         Hints.push_back(
9358             FixItHint::CreateInsertion(E->getBeginLoc(), CastFix.str()));
9359       } else {
9360         // Otherwise, add parens around the expression as well as the cast.
9361         CastFix << "(";
9362         Hints.push_back(
9363             FixItHint::CreateInsertion(E->getBeginLoc(), CastFix.str()));
9364 
9365         SourceLocation After = S.getLocForEndOfToken(E->getEndLoc());
9366         Hints.push_back(FixItHint::CreateInsertion(After, ")"));
9367       }
9368 
9369       if (ShouldNotPrintDirectly) {
9370         // The expression has a type that should not be printed directly.
9371         // We extract the name from the typedef because we don't want to show
9372         // the underlying type in the diagnostic.
9373         StringRef Name;
9374         if (const TypedefType *TypedefTy = dyn_cast<TypedefType>(ExprTy))
9375           Name = TypedefTy->getDecl()->getName();
9376         else
9377           Name = CastTyName;
9378         unsigned Diag = Match == ArgType::NoMatchPedantic
9379                             ? diag::warn_format_argument_needs_cast_pedantic
9380                             : diag::warn_format_argument_needs_cast;
9381         EmitFormatDiagnostic(S.PDiag(Diag) << Name << IntendedTy << IsEnum
9382                                            << E->getSourceRange(),
9383                              E->getBeginLoc(), /*IsStringLocation=*/false,
9384                              SpecRange, Hints);
9385       } else {
9386         // In this case, the expression could be printed using a different
9387         // specifier, but we've decided that the specifier is probably correct
9388         // and we should cast instead. Just use the normal warning message.
9389         EmitFormatDiagnostic(
9390             S.PDiag(diag::warn_format_conversion_argument_type_mismatch)
9391                 << AT.getRepresentativeTypeName(S.Context) << ExprTy << IsEnum
9392                 << E->getSourceRange(),
9393             E->getBeginLoc(), /*IsStringLocation*/ false, SpecRange, Hints);
9394       }
9395     }
9396   } else {
9397     const CharSourceRange &CSR = getSpecifierRange(StartSpecifier,
9398                                                    SpecifierLen);
9399     // Since the warning for passing non-POD types to variadic functions
9400     // was deferred until now, we emit a warning for non-POD
9401     // arguments here.
9402     switch (S.isValidVarArgType(ExprTy)) {
9403     case Sema::VAK_Valid:
9404     case Sema::VAK_ValidInCXX11: {
9405       unsigned Diag;
9406       switch (Match) {
9407       case ArgType::Match: llvm_unreachable("expected non-matching");
9408       case ArgType::NoMatchPedantic:
9409         Diag = diag::warn_format_conversion_argument_type_mismatch_pedantic;
9410         break;
9411       case ArgType::NoMatchTypeConfusion:
9412         Diag = diag::warn_format_conversion_argument_type_mismatch_confusion;
9413         break;
9414       case ArgType::NoMatch:
9415         Diag = diag::warn_format_conversion_argument_type_mismatch;
9416         break;
9417       }
9418 
9419       EmitFormatDiagnostic(
9420           S.PDiag(Diag) << AT.getRepresentativeTypeName(S.Context) << ExprTy
9421                         << IsEnum << CSR << E->getSourceRange(),
9422           E->getBeginLoc(), /*IsStringLocation*/ false, CSR);
9423       break;
9424     }
9425     case Sema::VAK_Undefined:
9426     case Sema::VAK_MSVCUndefined:
9427       EmitFormatDiagnostic(S.PDiag(diag::warn_non_pod_vararg_with_format_string)
9428                                << S.getLangOpts().CPlusPlus11 << ExprTy
9429                                << CallType
9430                                << AT.getRepresentativeTypeName(S.Context) << CSR
9431                                << E->getSourceRange(),
9432                            E->getBeginLoc(), /*IsStringLocation*/ false, CSR);
9433       checkForCStrMembers(AT, E);
9434       break;
9435 
9436     case Sema::VAK_Invalid:
9437       if (ExprTy->isObjCObjectType())
9438         EmitFormatDiagnostic(
9439             S.PDiag(diag::err_cannot_pass_objc_interface_to_vararg_format)
9440                 << S.getLangOpts().CPlusPlus11 << ExprTy << CallType
9441                 << AT.getRepresentativeTypeName(S.Context) << CSR
9442                 << E->getSourceRange(),
9443             E->getBeginLoc(), /*IsStringLocation*/ false, CSR);
9444       else
9445         // FIXME: If this is an initializer list, suggest removing the braces
9446         // or inserting a cast to the target type.
9447         S.Diag(E->getBeginLoc(), diag::err_cannot_pass_to_vararg_format)
9448             << isa<InitListExpr>(E) << ExprTy << CallType
9449             << AT.getRepresentativeTypeName(S.Context) << E->getSourceRange();
9450       break;
9451     }
9452 
9453     assert(FirstDataArg + FS.getArgIndex() < CheckedVarArgs.size() &&
9454            "format string specifier index out of range");
9455     CheckedVarArgs[FirstDataArg + FS.getArgIndex()] = true;
9456   }
9457 
9458   return true;
9459 }
9460 
9461 //===--- CHECK: Scanf format string checking ------------------------------===//
9462 
9463 namespace {
9464 
9465 class CheckScanfHandler : public CheckFormatHandler {
9466 public:
9467   CheckScanfHandler(Sema &s, const FormatStringLiteral *fexpr,
9468                     const Expr *origFormatExpr, Sema::FormatStringType type,
9469                     unsigned firstDataArg, unsigned numDataArgs,
9470                     const char *beg, bool hasVAListArg,
9471                     ArrayRef<const Expr *> Args, unsigned formatIdx,
9472                     bool inFunctionCall, Sema::VariadicCallType CallType,
9473                     llvm::SmallBitVector &CheckedVarArgs,
9474                     UncoveredArgHandler &UncoveredArg)
9475       : CheckFormatHandler(s, fexpr, origFormatExpr, type, firstDataArg,
9476                            numDataArgs, beg, hasVAListArg, Args, formatIdx,
9477                            inFunctionCall, CallType, CheckedVarArgs,
9478                            UncoveredArg) {}
9479 
9480   bool HandleScanfSpecifier(const analyze_scanf::ScanfSpecifier &FS,
9481                             const char *startSpecifier,
9482                             unsigned specifierLen) override;
9483 
9484   bool HandleInvalidScanfConversionSpecifier(
9485           const analyze_scanf::ScanfSpecifier &FS,
9486           const char *startSpecifier,
9487           unsigned specifierLen) override;
9488 
9489   void HandleIncompleteScanList(const char *start, const char *end) override;
9490 };
9491 
9492 } // namespace
9493 
9494 void CheckScanfHandler::HandleIncompleteScanList(const char *start,
9495                                                  const char *end) {
9496   EmitFormatDiagnostic(S.PDiag(diag::warn_scanf_scanlist_incomplete),
9497                        getLocationOfByte(end), /*IsStringLocation*/true,
9498                        getSpecifierRange(start, end - start));
9499 }
9500 
9501 bool CheckScanfHandler::HandleInvalidScanfConversionSpecifier(
9502                                         const analyze_scanf::ScanfSpecifier &FS,
9503                                         const char *startSpecifier,
9504                                         unsigned specifierLen) {
9505   const analyze_scanf::ScanfConversionSpecifier &CS =
9506     FS.getConversionSpecifier();
9507 
9508   return HandleInvalidConversionSpecifier(FS.getArgIndex(),
9509                                           getLocationOfByte(CS.getStart()),
9510                                           startSpecifier, specifierLen,
9511                                           CS.getStart(), CS.getLength());
9512 }
9513 
9514 bool CheckScanfHandler::HandleScanfSpecifier(
9515                                        const analyze_scanf::ScanfSpecifier &FS,
9516                                        const char *startSpecifier,
9517                                        unsigned specifierLen) {
9518   using namespace analyze_scanf;
9519   using namespace analyze_format_string;
9520 
9521   const ScanfConversionSpecifier &CS = FS.getConversionSpecifier();
9522 
9523   // Handle case where '%' and '*' don't consume an argument.  These shouldn't
9524   // be used to decide if we are using positional arguments consistently.
9525   if (FS.consumesDataArgument()) {
9526     if (atFirstArg) {
9527       atFirstArg = false;
9528       usesPositionalArgs = FS.usesPositionalArg();
9529     }
9530     else if (usesPositionalArgs != FS.usesPositionalArg()) {
9531       HandlePositionalNonpositionalArgs(getLocationOfByte(CS.getStart()),
9532                                         startSpecifier, specifierLen);
9533       return false;
9534     }
9535   }
9536 
9537   // Check if the field with is non-zero.
9538   const OptionalAmount &Amt = FS.getFieldWidth();
9539   if (Amt.getHowSpecified() == OptionalAmount::Constant) {
9540     if (Amt.getConstantAmount() == 0) {
9541       const CharSourceRange &R = getSpecifierRange(Amt.getStart(),
9542                                                    Amt.getConstantLength());
9543       EmitFormatDiagnostic(S.PDiag(diag::warn_scanf_nonzero_width),
9544                            getLocationOfByte(Amt.getStart()),
9545                            /*IsStringLocation*/true, R,
9546                            FixItHint::CreateRemoval(R));
9547     }
9548   }
9549 
9550   if (!FS.consumesDataArgument()) {
9551     // FIXME: Technically specifying a precision or field width here
9552     // makes no sense.  Worth issuing a warning at some point.
9553     return true;
9554   }
9555 
9556   // Consume the argument.
9557   unsigned argIndex = FS.getArgIndex();
9558   if (argIndex < NumDataArgs) {
9559       // The check to see if the argIndex is valid will come later.
9560       // We set the bit here because we may exit early from this
9561       // function if we encounter some other error.
9562     CoveredArgs.set(argIndex);
9563   }
9564 
9565   // Check the length modifier is valid with the given conversion specifier.
9566   if (!FS.hasValidLengthModifier(S.getASTContext().getTargetInfo(),
9567                                  S.getLangOpts()))
9568     HandleInvalidLengthModifier(FS, CS, startSpecifier, specifierLen,
9569                                 diag::warn_format_nonsensical_length);
9570   else if (!FS.hasStandardLengthModifier())
9571     HandleNonStandardLengthModifier(FS, startSpecifier, specifierLen);
9572   else if (!FS.hasStandardLengthConversionCombination())
9573     HandleInvalidLengthModifier(FS, CS, startSpecifier, specifierLen,
9574                                 diag::warn_format_non_standard_conversion_spec);
9575 
9576   if (!FS.hasStandardConversionSpecifier(S.getLangOpts()))
9577     HandleNonStandardConversionSpecifier(CS, startSpecifier, specifierLen);
9578 
9579   // The remaining checks depend on the data arguments.
9580   if (HasVAListArg)
9581     return true;
9582 
9583   if (!CheckNumArgs(FS, CS, startSpecifier, specifierLen, argIndex))
9584     return false;
9585 
9586   // Check that the argument type matches the format specifier.
9587   const Expr *Ex = getDataArg(argIndex);
9588   if (!Ex)
9589     return true;
9590 
9591   const analyze_format_string::ArgType &AT = FS.getArgType(S.Context);
9592 
9593   if (!AT.isValid()) {
9594     return true;
9595   }
9596 
9597   analyze_format_string::ArgType::MatchKind Match =
9598       AT.matchesType(S.Context, Ex->getType());
9599   bool Pedantic = Match == analyze_format_string::ArgType::NoMatchPedantic;
9600   if (Match == analyze_format_string::ArgType::Match)
9601     return true;
9602 
9603   ScanfSpecifier fixedFS = FS;
9604   bool Success = fixedFS.fixType(Ex->getType(), Ex->IgnoreImpCasts()->getType(),
9605                                  S.getLangOpts(), S.Context);
9606 
9607   unsigned Diag =
9608       Pedantic ? diag::warn_format_conversion_argument_type_mismatch_pedantic
9609                : diag::warn_format_conversion_argument_type_mismatch;
9610 
9611   if (Success) {
9612     // Get the fix string from the fixed format specifier.
9613     SmallString<128> buf;
9614     llvm::raw_svector_ostream os(buf);
9615     fixedFS.toString(os);
9616 
9617     EmitFormatDiagnostic(
9618         S.PDiag(Diag) << AT.getRepresentativeTypeName(S.Context)
9619                       << Ex->getType() << false << Ex->getSourceRange(),
9620         Ex->getBeginLoc(),
9621         /*IsStringLocation*/ false,
9622         getSpecifierRange(startSpecifier, specifierLen),
9623         FixItHint::CreateReplacement(
9624             getSpecifierRange(startSpecifier, specifierLen), os.str()));
9625   } else {
9626     EmitFormatDiagnostic(S.PDiag(Diag)
9627                              << AT.getRepresentativeTypeName(S.Context)
9628                              << Ex->getType() << false << Ex->getSourceRange(),
9629                          Ex->getBeginLoc(),
9630                          /*IsStringLocation*/ false,
9631                          getSpecifierRange(startSpecifier, specifierLen));
9632   }
9633 
9634   return true;
9635 }
9636 
9637 static void CheckFormatString(Sema &S, const FormatStringLiteral *FExpr,
9638                               const Expr *OrigFormatExpr,
9639                               ArrayRef<const Expr *> Args,
9640                               bool HasVAListArg, unsigned format_idx,
9641                               unsigned firstDataArg,
9642                               Sema::FormatStringType Type,
9643                               bool inFunctionCall,
9644                               Sema::VariadicCallType CallType,
9645                               llvm::SmallBitVector &CheckedVarArgs,
9646                               UncoveredArgHandler &UncoveredArg,
9647                               bool IgnoreStringsWithoutSpecifiers) {
9648   // CHECK: is the format string a wide literal?
9649   if (!FExpr->isAscii() && !FExpr->isUTF8()) {
9650     CheckFormatHandler::EmitFormatDiagnostic(
9651         S, inFunctionCall, Args[format_idx],
9652         S.PDiag(diag::warn_format_string_is_wide_literal), FExpr->getBeginLoc(),
9653         /*IsStringLocation*/ true, OrigFormatExpr->getSourceRange());
9654     return;
9655   }
9656 
9657   // Str - The format string.  NOTE: this is NOT null-terminated!
9658   StringRef StrRef = FExpr->getString();
9659   const char *Str = StrRef.data();
9660   // Account for cases where the string literal is truncated in a declaration.
9661   const ConstantArrayType *T =
9662     S.Context.getAsConstantArrayType(FExpr->getType());
9663   assert(T && "String literal not of constant array type!");
9664   size_t TypeSize = T->getSize().getZExtValue();
9665   size_t StrLen = std::min(std::max(TypeSize, size_t(1)) - 1, StrRef.size());
9666   const unsigned numDataArgs = Args.size() - firstDataArg;
9667 
9668   if (IgnoreStringsWithoutSpecifiers &&
9669       !analyze_format_string::parseFormatStringHasFormattingSpecifiers(
9670           Str, Str + StrLen, S.getLangOpts(), S.Context.getTargetInfo()))
9671     return;
9672 
9673   // Emit a warning if the string literal is truncated and does not contain an
9674   // embedded null character.
9675   if (TypeSize <= StrRef.size() &&
9676       StrRef.substr(0, TypeSize).find('\0') == StringRef::npos) {
9677     CheckFormatHandler::EmitFormatDiagnostic(
9678         S, inFunctionCall, Args[format_idx],
9679         S.PDiag(diag::warn_printf_format_string_not_null_terminated),
9680         FExpr->getBeginLoc(),
9681         /*IsStringLocation=*/true, OrigFormatExpr->getSourceRange());
9682     return;
9683   }
9684 
9685   // CHECK: empty format string?
9686   if (StrLen == 0 && numDataArgs > 0) {
9687     CheckFormatHandler::EmitFormatDiagnostic(
9688         S, inFunctionCall, Args[format_idx],
9689         S.PDiag(diag::warn_empty_format_string), FExpr->getBeginLoc(),
9690         /*IsStringLocation*/ true, OrigFormatExpr->getSourceRange());
9691     return;
9692   }
9693 
9694   if (Type == Sema::FST_Printf || Type == Sema::FST_NSString ||
9695       Type == Sema::FST_FreeBSDKPrintf || Type == Sema::FST_OSLog ||
9696       Type == Sema::FST_OSTrace) {
9697     CheckPrintfHandler H(
9698         S, FExpr, OrigFormatExpr, Type, firstDataArg, numDataArgs,
9699         (Type == Sema::FST_NSString || Type == Sema::FST_OSTrace), Str,
9700         HasVAListArg, Args, format_idx, inFunctionCall, CallType,
9701         CheckedVarArgs, UncoveredArg);
9702 
9703     if (!analyze_format_string::ParsePrintfString(H, Str, Str + StrLen,
9704                                                   S.getLangOpts(),
9705                                                   S.Context.getTargetInfo(),
9706                                             Type == Sema::FST_FreeBSDKPrintf))
9707       H.DoneProcessing();
9708   } else if (Type == Sema::FST_Scanf) {
9709     CheckScanfHandler H(S, FExpr, OrigFormatExpr, Type, firstDataArg,
9710                         numDataArgs, Str, HasVAListArg, Args, format_idx,
9711                         inFunctionCall, CallType, CheckedVarArgs, UncoveredArg);
9712 
9713     if (!analyze_format_string::ParseScanfString(H, Str, Str + StrLen,
9714                                                  S.getLangOpts(),
9715                                                  S.Context.getTargetInfo()))
9716       H.DoneProcessing();
9717   } // TODO: handle other formats
9718 }
9719 
9720 bool Sema::FormatStringHasSArg(const StringLiteral *FExpr) {
9721   // Str - The format string.  NOTE: this is NOT null-terminated!
9722   StringRef StrRef = FExpr->getString();
9723   const char *Str = StrRef.data();
9724   // Account for cases where the string literal is truncated in a declaration.
9725   const ConstantArrayType *T = Context.getAsConstantArrayType(FExpr->getType());
9726   assert(T && "String literal not of constant array type!");
9727   size_t TypeSize = T->getSize().getZExtValue();
9728   size_t StrLen = std::min(std::max(TypeSize, size_t(1)) - 1, StrRef.size());
9729   return analyze_format_string::ParseFormatStringHasSArg(Str, Str + StrLen,
9730                                                          getLangOpts(),
9731                                                          Context.getTargetInfo());
9732 }
9733 
9734 //===--- CHECK: Warn on use of wrong absolute value function. -------------===//
9735 
9736 // Returns the related absolute value function that is larger, of 0 if one
9737 // does not exist.
9738 static unsigned getLargerAbsoluteValueFunction(unsigned AbsFunction) {
9739   switch (AbsFunction) {
9740   default:
9741     return 0;
9742 
9743   case Builtin::BI__builtin_abs:
9744     return Builtin::BI__builtin_labs;
9745   case Builtin::BI__builtin_labs:
9746     return Builtin::BI__builtin_llabs;
9747   case Builtin::BI__builtin_llabs:
9748     return 0;
9749 
9750   case Builtin::BI__builtin_fabsf:
9751     return Builtin::BI__builtin_fabs;
9752   case Builtin::BI__builtin_fabs:
9753     return Builtin::BI__builtin_fabsl;
9754   case Builtin::BI__builtin_fabsl:
9755     return 0;
9756 
9757   case Builtin::BI__builtin_cabsf:
9758     return Builtin::BI__builtin_cabs;
9759   case Builtin::BI__builtin_cabs:
9760     return Builtin::BI__builtin_cabsl;
9761   case Builtin::BI__builtin_cabsl:
9762     return 0;
9763 
9764   case Builtin::BIabs:
9765     return Builtin::BIlabs;
9766   case Builtin::BIlabs:
9767     return Builtin::BIllabs;
9768   case Builtin::BIllabs:
9769     return 0;
9770 
9771   case Builtin::BIfabsf:
9772     return Builtin::BIfabs;
9773   case Builtin::BIfabs:
9774     return Builtin::BIfabsl;
9775   case Builtin::BIfabsl:
9776     return 0;
9777 
9778   case Builtin::BIcabsf:
9779    return Builtin::BIcabs;
9780   case Builtin::BIcabs:
9781     return Builtin::BIcabsl;
9782   case Builtin::BIcabsl:
9783     return 0;
9784   }
9785 }
9786 
9787 // Returns the argument type of the absolute value function.
9788 static QualType getAbsoluteValueArgumentType(ASTContext &Context,
9789                                              unsigned AbsType) {
9790   if (AbsType == 0)
9791     return QualType();
9792 
9793   ASTContext::GetBuiltinTypeError Error = ASTContext::GE_None;
9794   QualType BuiltinType = Context.GetBuiltinType(AbsType, Error);
9795   if (Error != ASTContext::GE_None)
9796     return QualType();
9797 
9798   const FunctionProtoType *FT = BuiltinType->getAs<FunctionProtoType>();
9799   if (!FT)
9800     return QualType();
9801 
9802   if (FT->getNumParams() != 1)
9803     return QualType();
9804 
9805   return FT->getParamType(0);
9806 }
9807 
9808 // Returns the best absolute value function, or zero, based on type and
9809 // current absolute value function.
9810 static unsigned getBestAbsFunction(ASTContext &Context, QualType ArgType,
9811                                    unsigned AbsFunctionKind) {
9812   unsigned BestKind = 0;
9813   uint64_t ArgSize = Context.getTypeSize(ArgType);
9814   for (unsigned Kind = AbsFunctionKind; Kind != 0;
9815        Kind = getLargerAbsoluteValueFunction(Kind)) {
9816     QualType ParamType = getAbsoluteValueArgumentType(Context, Kind);
9817     if (Context.getTypeSize(ParamType) >= ArgSize) {
9818       if (BestKind == 0)
9819         BestKind = Kind;
9820       else if (Context.hasSameType(ParamType, ArgType)) {
9821         BestKind = Kind;
9822         break;
9823       }
9824     }
9825   }
9826   return BestKind;
9827 }
9828 
9829 enum AbsoluteValueKind {
9830   AVK_Integer,
9831   AVK_Floating,
9832   AVK_Complex
9833 };
9834 
9835 static AbsoluteValueKind getAbsoluteValueKind(QualType T) {
9836   if (T->isIntegralOrEnumerationType())
9837     return AVK_Integer;
9838   if (T->isRealFloatingType())
9839     return AVK_Floating;
9840   if (T->isAnyComplexType())
9841     return AVK_Complex;
9842 
9843   llvm_unreachable("Type not integer, floating, or complex");
9844 }
9845 
9846 // Changes the absolute value function to a different type.  Preserves whether
9847 // the function is a builtin.
9848 static unsigned changeAbsFunction(unsigned AbsKind,
9849                                   AbsoluteValueKind ValueKind) {
9850   switch (ValueKind) {
9851   case AVK_Integer:
9852     switch (AbsKind) {
9853     default:
9854       return 0;
9855     case Builtin::BI__builtin_fabsf:
9856     case Builtin::BI__builtin_fabs:
9857     case Builtin::BI__builtin_fabsl:
9858     case Builtin::BI__builtin_cabsf:
9859     case Builtin::BI__builtin_cabs:
9860     case Builtin::BI__builtin_cabsl:
9861       return Builtin::BI__builtin_abs;
9862     case Builtin::BIfabsf:
9863     case Builtin::BIfabs:
9864     case Builtin::BIfabsl:
9865     case Builtin::BIcabsf:
9866     case Builtin::BIcabs:
9867     case Builtin::BIcabsl:
9868       return Builtin::BIabs;
9869     }
9870   case AVK_Floating:
9871     switch (AbsKind) {
9872     default:
9873       return 0;
9874     case Builtin::BI__builtin_abs:
9875     case Builtin::BI__builtin_labs:
9876     case Builtin::BI__builtin_llabs:
9877     case Builtin::BI__builtin_cabsf:
9878     case Builtin::BI__builtin_cabs:
9879     case Builtin::BI__builtin_cabsl:
9880       return Builtin::BI__builtin_fabsf;
9881     case Builtin::BIabs:
9882     case Builtin::BIlabs:
9883     case Builtin::BIllabs:
9884     case Builtin::BIcabsf:
9885     case Builtin::BIcabs:
9886     case Builtin::BIcabsl:
9887       return Builtin::BIfabsf;
9888     }
9889   case AVK_Complex:
9890     switch (AbsKind) {
9891     default:
9892       return 0;
9893     case Builtin::BI__builtin_abs:
9894     case Builtin::BI__builtin_labs:
9895     case Builtin::BI__builtin_llabs:
9896     case Builtin::BI__builtin_fabsf:
9897     case Builtin::BI__builtin_fabs:
9898     case Builtin::BI__builtin_fabsl:
9899       return Builtin::BI__builtin_cabsf;
9900     case Builtin::BIabs:
9901     case Builtin::BIlabs:
9902     case Builtin::BIllabs:
9903     case Builtin::BIfabsf:
9904     case Builtin::BIfabs:
9905     case Builtin::BIfabsl:
9906       return Builtin::BIcabsf;
9907     }
9908   }
9909   llvm_unreachable("Unable to convert function");
9910 }
9911 
9912 static unsigned getAbsoluteValueFunctionKind(const FunctionDecl *FDecl) {
9913   const IdentifierInfo *FnInfo = FDecl->getIdentifier();
9914   if (!FnInfo)
9915     return 0;
9916 
9917   switch (FDecl->getBuiltinID()) {
9918   default:
9919     return 0;
9920   case Builtin::BI__builtin_abs:
9921   case Builtin::BI__builtin_fabs:
9922   case Builtin::BI__builtin_fabsf:
9923   case Builtin::BI__builtin_fabsl:
9924   case Builtin::BI__builtin_labs:
9925   case Builtin::BI__builtin_llabs:
9926   case Builtin::BI__builtin_cabs:
9927   case Builtin::BI__builtin_cabsf:
9928   case Builtin::BI__builtin_cabsl:
9929   case Builtin::BIabs:
9930   case Builtin::BIlabs:
9931   case Builtin::BIllabs:
9932   case Builtin::BIfabs:
9933   case Builtin::BIfabsf:
9934   case Builtin::BIfabsl:
9935   case Builtin::BIcabs:
9936   case Builtin::BIcabsf:
9937   case Builtin::BIcabsl:
9938     return FDecl->getBuiltinID();
9939   }
9940   llvm_unreachable("Unknown Builtin type");
9941 }
9942 
9943 // If the replacement is valid, emit a note with replacement function.
9944 // Additionally, suggest including the proper header if not already included.
9945 static void emitReplacement(Sema &S, SourceLocation Loc, SourceRange Range,
9946                             unsigned AbsKind, QualType ArgType) {
9947   bool EmitHeaderHint = true;
9948   const char *HeaderName = nullptr;
9949   const char *FunctionName = nullptr;
9950   if (S.getLangOpts().CPlusPlus && !ArgType->isAnyComplexType()) {
9951     FunctionName = "std::abs";
9952     if (ArgType->isIntegralOrEnumerationType()) {
9953       HeaderName = "cstdlib";
9954     } else if (ArgType->isRealFloatingType()) {
9955       HeaderName = "cmath";
9956     } else {
9957       llvm_unreachable("Invalid Type");
9958     }
9959 
9960     // Lookup all std::abs
9961     if (NamespaceDecl *Std = S.getStdNamespace()) {
9962       LookupResult R(S, &S.Context.Idents.get("abs"), Loc, Sema::LookupAnyName);
9963       R.suppressDiagnostics();
9964       S.LookupQualifiedName(R, Std);
9965 
9966       for (const auto *I : R) {
9967         const FunctionDecl *FDecl = nullptr;
9968         if (const UsingShadowDecl *UsingD = dyn_cast<UsingShadowDecl>(I)) {
9969           FDecl = dyn_cast<FunctionDecl>(UsingD->getTargetDecl());
9970         } else {
9971           FDecl = dyn_cast<FunctionDecl>(I);
9972         }
9973         if (!FDecl)
9974           continue;
9975 
9976         // Found std::abs(), check that they are the right ones.
9977         if (FDecl->getNumParams() != 1)
9978           continue;
9979 
9980         // Check that the parameter type can handle the argument.
9981         QualType ParamType = FDecl->getParamDecl(0)->getType();
9982         if (getAbsoluteValueKind(ArgType) == getAbsoluteValueKind(ParamType) &&
9983             S.Context.getTypeSize(ArgType) <=
9984                 S.Context.getTypeSize(ParamType)) {
9985           // Found a function, don't need the header hint.
9986           EmitHeaderHint = false;
9987           break;
9988         }
9989       }
9990     }
9991   } else {
9992     FunctionName = S.Context.BuiltinInfo.getName(AbsKind);
9993     HeaderName = S.Context.BuiltinInfo.getHeaderName(AbsKind);
9994 
9995     if (HeaderName) {
9996       DeclarationName DN(&S.Context.Idents.get(FunctionName));
9997       LookupResult R(S, DN, Loc, Sema::LookupAnyName);
9998       R.suppressDiagnostics();
9999       S.LookupName(R, S.getCurScope());
10000 
10001       if (R.isSingleResult()) {
10002         FunctionDecl *FD = dyn_cast<FunctionDecl>(R.getFoundDecl());
10003         if (FD && FD->getBuiltinID() == AbsKind) {
10004           EmitHeaderHint = false;
10005         } else {
10006           return;
10007         }
10008       } else if (!R.empty()) {
10009         return;
10010       }
10011     }
10012   }
10013 
10014   S.Diag(Loc, diag::note_replace_abs_function)
10015       << FunctionName << FixItHint::CreateReplacement(Range, FunctionName);
10016 
10017   if (!HeaderName)
10018     return;
10019 
10020   if (!EmitHeaderHint)
10021     return;
10022 
10023   S.Diag(Loc, diag::note_include_header_or_declare) << HeaderName
10024                                                     << FunctionName;
10025 }
10026 
10027 template <std::size_t StrLen>
10028 static bool IsStdFunction(const FunctionDecl *FDecl,
10029                           const char (&Str)[StrLen]) {
10030   if (!FDecl)
10031     return false;
10032   if (!FDecl->getIdentifier() || !FDecl->getIdentifier()->isStr(Str))
10033     return false;
10034   if (!FDecl->isInStdNamespace())
10035     return false;
10036 
10037   return true;
10038 }
10039 
10040 // Warn when using the wrong abs() function.
10041 void Sema::CheckAbsoluteValueFunction(const CallExpr *Call,
10042                                       const FunctionDecl *FDecl) {
10043   if (Call->getNumArgs() != 1)
10044     return;
10045 
10046   unsigned AbsKind = getAbsoluteValueFunctionKind(FDecl);
10047   bool IsStdAbs = IsStdFunction(FDecl, "abs");
10048   if (AbsKind == 0 && !IsStdAbs)
10049     return;
10050 
10051   QualType ArgType = Call->getArg(0)->IgnoreParenImpCasts()->getType();
10052   QualType ParamType = Call->getArg(0)->getType();
10053 
10054   // Unsigned types cannot be negative.  Suggest removing the absolute value
10055   // function call.
10056   if (ArgType->isUnsignedIntegerType()) {
10057     const char *FunctionName =
10058         IsStdAbs ? "std::abs" : Context.BuiltinInfo.getName(AbsKind);
10059     Diag(Call->getExprLoc(), diag::warn_unsigned_abs) << ArgType << ParamType;
10060     Diag(Call->getExprLoc(), diag::note_remove_abs)
10061         << FunctionName
10062         << FixItHint::CreateRemoval(Call->getCallee()->getSourceRange());
10063     return;
10064   }
10065 
10066   // Taking the absolute value of a pointer is very suspicious, they probably
10067   // wanted to index into an array, dereference a pointer, call a function, etc.
10068   if (ArgType->isPointerType() || ArgType->canDecayToPointerType()) {
10069     unsigned DiagType = 0;
10070     if (ArgType->isFunctionType())
10071       DiagType = 1;
10072     else if (ArgType->isArrayType())
10073       DiagType = 2;
10074 
10075     Diag(Call->getExprLoc(), diag::warn_pointer_abs) << DiagType << ArgType;
10076     return;
10077   }
10078 
10079   // std::abs has overloads which prevent most of the absolute value problems
10080   // from occurring.
10081   if (IsStdAbs)
10082     return;
10083 
10084   AbsoluteValueKind ArgValueKind = getAbsoluteValueKind(ArgType);
10085   AbsoluteValueKind ParamValueKind = getAbsoluteValueKind(ParamType);
10086 
10087   // The argument and parameter are the same kind.  Check if they are the right
10088   // size.
10089   if (ArgValueKind == ParamValueKind) {
10090     if (Context.getTypeSize(ArgType) <= Context.getTypeSize(ParamType))
10091       return;
10092 
10093     unsigned NewAbsKind = getBestAbsFunction(Context, ArgType, AbsKind);
10094     Diag(Call->getExprLoc(), diag::warn_abs_too_small)
10095         << FDecl << ArgType << ParamType;
10096 
10097     if (NewAbsKind == 0)
10098       return;
10099 
10100     emitReplacement(*this, Call->getExprLoc(),
10101                     Call->getCallee()->getSourceRange(), NewAbsKind, ArgType);
10102     return;
10103   }
10104 
10105   // ArgValueKind != ParamValueKind
10106   // The wrong type of absolute value function was used.  Attempt to find the
10107   // proper one.
10108   unsigned NewAbsKind = changeAbsFunction(AbsKind, ArgValueKind);
10109   NewAbsKind = getBestAbsFunction(Context, ArgType, NewAbsKind);
10110   if (NewAbsKind == 0)
10111     return;
10112 
10113   Diag(Call->getExprLoc(), diag::warn_wrong_absolute_value_type)
10114       << FDecl << ParamValueKind << ArgValueKind;
10115 
10116   emitReplacement(*this, Call->getExprLoc(),
10117                   Call->getCallee()->getSourceRange(), NewAbsKind, ArgType);
10118 }
10119 
10120 //===--- CHECK: Warn on use of std::max and unsigned zero. r---------------===//
10121 void Sema::CheckMaxUnsignedZero(const CallExpr *Call,
10122                                 const FunctionDecl *FDecl) {
10123   if (!Call || !FDecl) return;
10124 
10125   // Ignore template specializations and macros.
10126   if (inTemplateInstantiation()) return;
10127   if (Call->getExprLoc().isMacroID()) return;
10128 
10129   // Only care about the one template argument, two function parameter std::max
10130   if (Call->getNumArgs() != 2) return;
10131   if (!IsStdFunction(FDecl, "max")) return;
10132   const auto * ArgList = FDecl->getTemplateSpecializationArgs();
10133   if (!ArgList) return;
10134   if (ArgList->size() != 1) return;
10135 
10136   // Check that template type argument is unsigned integer.
10137   const auto& TA = ArgList->get(0);
10138   if (TA.getKind() != TemplateArgument::Type) return;
10139   QualType ArgType = TA.getAsType();
10140   if (!ArgType->isUnsignedIntegerType()) return;
10141 
10142   // See if either argument is a literal zero.
10143   auto IsLiteralZeroArg = [](const Expr* E) -> bool {
10144     const auto *MTE = dyn_cast<MaterializeTemporaryExpr>(E);
10145     if (!MTE) return false;
10146     const auto *Num = dyn_cast<IntegerLiteral>(MTE->getSubExpr());
10147     if (!Num) return false;
10148     if (Num->getValue() != 0) return false;
10149     return true;
10150   };
10151 
10152   const Expr *FirstArg = Call->getArg(0);
10153   const Expr *SecondArg = Call->getArg(1);
10154   const bool IsFirstArgZero = IsLiteralZeroArg(FirstArg);
10155   const bool IsSecondArgZero = IsLiteralZeroArg(SecondArg);
10156 
10157   // Only warn when exactly one argument is zero.
10158   if (IsFirstArgZero == IsSecondArgZero) return;
10159 
10160   SourceRange FirstRange = FirstArg->getSourceRange();
10161   SourceRange SecondRange = SecondArg->getSourceRange();
10162 
10163   SourceRange ZeroRange = IsFirstArgZero ? FirstRange : SecondRange;
10164 
10165   Diag(Call->getExprLoc(), diag::warn_max_unsigned_zero)
10166       << IsFirstArgZero << Call->getCallee()->getSourceRange() << ZeroRange;
10167 
10168   // Deduce what parts to remove so that "std::max(0u, foo)" becomes "(foo)".
10169   SourceRange RemovalRange;
10170   if (IsFirstArgZero) {
10171     RemovalRange = SourceRange(FirstRange.getBegin(),
10172                                SecondRange.getBegin().getLocWithOffset(-1));
10173   } else {
10174     RemovalRange = SourceRange(getLocForEndOfToken(FirstRange.getEnd()),
10175                                SecondRange.getEnd());
10176   }
10177 
10178   Diag(Call->getExprLoc(), diag::note_remove_max_call)
10179         << FixItHint::CreateRemoval(Call->getCallee()->getSourceRange())
10180         << FixItHint::CreateRemoval(RemovalRange);
10181 }
10182 
10183 //===--- CHECK: Standard memory functions ---------------------------------===//
10184 
10185 /// Takes the expression passed to the size_t parameter of functions
10186 /// such as memcmp, strncat, etc and warns if it's a comparison.
10187 ///
10188 /// This is to catch typos like `if (memcmp(&a, &b, sizeof(a) > 0))`.
10189 static bool CheckMemorySizeofForComparison(Sema &S, const Expr *E,
10190                                            IdentifierInfo *FnName,
10191                                            SourceLocation FnLoc,
10192                                            SourceLocation RParenLoc) {
10193   const BinaryOperator *Size = dyn_cast<BinaryOperator>(E);
10194   if (!Size)
10195     return false;
10196 
10197   // if E is binop and op is <=>, >, <, >=, <=, ==, &&, ||:
10198   if (!Size->isComparisonOp() && !Size->isLogicalOp())
10199     return false;
10200 
10201   SourceRange SizeRange = Size->getSourceRange();
10202   S.Diag(Size->getOperatorLoc(), diag::warn_memsize_comparison)
10203       << SizeRange << FnName;
10204   S.Diag(FnLoc, diag::note_memsize_comparison_paren)
10205       << FnName
10206       << FixItHint::CreateInsertion(
10207              S.getLocForEndOfToken(Size->getLHS()->getEndLoc()), ")")
10208       << FixItHint::CreateRemoval(RParenLoc);
10209   S.Diag(SizeRange.getBegin(), diag::note_memsize_comparison_cast_silence)
10210       << FixItHint::CreateInsertion(SizeRange.getBegin(), "(size_t)(")
10211       << FixItHint::CreateInsertion(S.getLocForEndOfToken(SizeRange.getEnd()),
10212                                     ")");
10213 
10214   return true;
10215 }
10216 
10217 /// Determine whether the given type is or contains a dynamic class type
10218 /// (e.g., whether it has a vtable).
10219 static const CXXRecordDecl *getContainedDynamicClass(QualType T,
10220                                                      bool &IsContained) {
10221   // Look through array types while ignoring qualifiers.
10222   const Type *Ty = T->getBaseElementTypeUnsafe();
10223   IsContained = false;
10224 
10225   const CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
10226   RD = RD ? RD->getDefinition() : nullptr;
10227   if (!RD || RD->isInvalidDecl())
10228     return nullptr;
10229 
10230   if (RD->isDynamicClass())
10231     return RD;
10232 
10233   // Check all the fields.  If any bases were dynamic, the class is dynamic.
10234   // It's impossible for a class to transitively contain itself by value, so
10235   // infinite recursion is impossible.
10236   for (auto *FD : RD->fields()) {
10237     bool SubContained;
10238     if (const CXXRecordDecl *ContainedRD =
10239             getContainedDynamicClass(FD->getType(), SubContained)) {
10240       IsContained = true;
10241       return ContainedRD;
10242     }
10243   }
10244 
10245   return nullptr;
10246 }
10247 
10248 static const UnaryExprOrTypeTraitExpr *getAsSizeOfExpr(const Expr *E) {
10249   if (const auto *Unary = dyn_cast<UnaryExprOrTypeTraitExpr>(E))
10250     if (Unary->getKind() == UETT_SizeOf)
10251       return Unary;
10252   return nullptr;
10253 }
10254 
10255 /// If E is a sizeof expression, returns its argument expression,
10256 /// otherwise returns NULL.
10257 static const Expr *getSizeOfExprArg(const Expr *E) {
10258   if (const UnaryExprOrTypeTraitExpr *SizeOf = getAsSizeOfExpr(E))
10259     if (!SizeOf->isArgumentType())
10260       return SizeOf->getArgumentExpr()->IgnoreParenImpCasts();
10261   return nullptr;
10262 }
10263 
10264 /// If E is a sizeof expression, returns its argument type.
10265 static QualType getSizeOfArgType(const Expr *E) {
10266   if (const UnaryExprOrTypeTraitExpr *SizeOf = getAsSizeOfExpr(E))
10267     return SizeOf->getTypeOfArgument();
10268   return QualType();
10269 }
10270 
10271 namespace {
10272 
10273 struct SearchNonTrivialToInitializeField
10274     : DefaultInitializedTypeVisitor<SearchNonTrivialToInitializeField> {
10275   using Super =
10276       DefaultInitializedTypeVisitor<SearchNonTrivialToInitializeField>;
10277 
10278   SearchNonTrivialToInitializeField(const Expr *E, Sema &S) : E(E), S(S) {}
10279 
10280   void visitWithKind(QualType::PrimitiveDefaultInitializeKind PDIK, QualType FT,
10281                      SourceLocation SL) {
10282     if (const auto *AT = asDerived().getContext().getAsArrayType(FT)) {
10283       asDerived().visitArray(PDIK, AT, SL);
10284       return;
10285     }
10286 
10287     Super::visitWithKind(PDIK, FT, SL);
10288   }
10289 
10290   void visitARCStrong(QualType FT, SourceLocation SL) {
10291     S.DiagRuntimeBehavior(SL, E, S.PDiag(diag::note_nontrivial_field) << 1);
10292   }
10293   void visitARCWeak(QualType FT, SourceLocation SL) {
10294     S.DiagRuntimeBehavior(SL, E, S.PDiag(diag::note_nontrivial_field) << 1);
10295   }
10296   void visitStruct(QualType FT, SourceLocation SL) {
10297     for (const FieldDecl *FD : FT->castAs<RecordType>()->getDecl()->fields())
10298       visit(FD->getType(), FD->getLocation());
10299   }
10300   void visitArray(QualType::PrimitiveDefaultInitializeKind PDIK,
10301                   const ArrayType *AT, SourceLocation SL) {
10302     visit(getContext().getBaseElementType(AT), SL);
10303   }
10304   void visitTrivial(QualType FT, SourceLocation SL) {}
10305 
10306   static void diag(QualType RT, const Expr *E, Sema &S) {
10307     SearchNonTrivialToInitializeField(E, S).visitStruct(RT, SourceLocation());
10308   }
10309 
10310   ASTContext &getContext() { return S.getASTContext(); }
10311 
10312   const Expr *E;
10313   Sema &S;
10314 };
10315 
10316 struct SearchNonTrivialToCopyField
10317     : CopiedTypeVisitor<SearchNonTrivialToCopyField, false> {
10318   using Super = CopiedTypeVisitor<SearchNonTrivialToCopyField, false>;
10319 
10320   SearchNonTrivialToCopyField(const Expr *E, Sema &S) : E(E), S(S) {}
10321 
10322   void visitWithKind(QualType::PrimitiveCopyKind PCK, QualType FT,
10323                      SourceLocation SL) {
10324     if (const auto *AT = asDerived().getContext().getAsArrayType(FT)) {
10325       asDerived().visitArray(PCK, AT, SL);
10326       return;
10327     }
10328 
10329     Super::visitWithKind(PCK, FT, SL);
10330   }
10331 
10332   void visitARCStrong(QualType FT, SourceLocation SL) {
10333     S.DiagRuntimeBehavior(SL, E, S.PDiag(diag::note_nontrivial_field) << 0);
10334   }
10335   void visitARCWeak(QualType FT, SourceLocation SL) {
10336     S.DiagRuntimeBehavior(SL, E, S.PDiag(diag::note_nontrivial_field) << 0);
10337   }
10338   void visitStruct(QualType FT, SourceLocation SL) {
10339     for (const FieldDecl *FD : FT->castAs<RecordType>()->getDecl()->fields())
10340       visit(FD->getType(), FD->getLocation());
10341   }
10342   void visitArray(QualType::PrimitiveCopyKind PCK, const ArrayType *AT,
10343                   SourceLocation SL) {
10344     visit(getContext().getBaseElementType(AT), SL);
10345   }
10346   void preVisit(QualType::PrimitiveCopyKind PCK, QualType FT,
10347                 SourceLocation SL) {}
10348   void visitTrivial(QualType FT, SourceLocation SL) {}
10349   void visitVolatileTrivial(QualType FT, SourceLocation SL) {}
10350 
10351   static void diag(QualType RT, const Expr *E, Sema &S) {
10352     SearchNonTrivialToCopyField(E, S).visitStruct(RT, SourceLocation());
10353   }
10354 
10355   ASTContext &getContext() { return S.getASTContext(); }
10356 
10357   const Expr *E;
10358   Sema &S;
10359 };
10360 
10361 }
10362 
10363 /// Detect if \c SizeofExpr is likely to calculate the sizeof an object.
10364 static bool doesExprLikelyComputeSize(const Expr *SizeofExpr) {
10365   SizeofExpr = SizeofExpr->IgnoreParenImpCasts();
10366 
10367   if (const auto *BO = dyn_cast<BinaryOperator>(SizeofExpr)) {
10368     if (BO->getOpcode() != BO_Mul && BO->getOpcode() != BO_Add)
10369       return false;
10370 
10371     return doesExprLikelyComputeSize(BO->getLHS()) ||
10372            doesExprLikelyComputeSize(BO->getRHS());
10373   }
10374 
10375   return getAsSizeOfExpr(SizeofExpr) != nullptr;
10376 }
10377 
10378 /// Check if the ArgLoc originated from a macro passed to the call at CallLoc.
10379 ///
10380 /// \code
10381 ///   #define MACRO 0
10382 ///   foo(MACRO);
10383 ///   foo(0);
10384 /// \endcode
10385 ///
10386 /// This should return true for the first call to foo, but not for the second
10387 /// (regardless of whether foo is a macro or function).
10388 static bool isArgumentExpandedFromMacro(SourceManager &SM,
10389                                         SourceLocation CallLoc,
10390                                         SourceLocation ArgLoc) {
10391   if (!CallLoc.isMacroID())
10392     return SM.getFileID(CallLoc) != SM.getFileID(ArgLoc);
10393 
10394   return SM.getFileID(SM.getImmediateMacroCallerLoc(CallLoc)) !=
10395          SM.getFileID(SM.getImmediateMacroCallerLoc(ArgLoc));
10396 }
10397 
10398 /// Diagnose cases like 'memset(buf, sizeof(buf), 0)', which should have the
10399 /// last two arguments transposed.
10400 static void CheckMemaccessSize(Sema &S, unsigned BId, const CallExpr *Call) {
10401   if (BId != Builtin::BImemset && BId != Builtin::BIbzero)
10402     return;
10403 
10404   const Expr *SizeArg =
10405     Call->getArg(BId == Builtin::BImemset ? 2 : 1)->IgnoreImpCasts();
10406 
10407   auto isLiteralZero = [](const Expr *E) {
10408     return isa<IntegerLiteral>(E) && cast<IntegerLiteral>(E)->getValue() == 0;
10409   };
10410 
10411   // If we're memsetting or bzeroing 0 bytes, then this is likely an error.
10412   SourceLocation CallLoc = Call->getRParenLoc();
10413   SourceManager &SM = S.getSourceManager();
10414   if (isLiteralZero(SizeArg) &&
10415       !isArgumentExpandedFromMacro(SM, CallLoc, SizeArg->getExprLoc())) {
10416 
10417     SourceLocation DiagLoc = SizeArg->getExprLoc();
10418 
10419     // Some platforms #define bzero to __builtin_memset. See if this is the
10420     // case, and if so, emit a better diagnostic.
10421     if (BId == Builtin::BIbzero ||
10422         (CallLoc.isMacroID() && Lexer::getImmediateMacroName(
10423                                     CallLoc, SM, S.getLangOpts()) == "bzero")) {
10424       S.Diag(DiagLoc, diag::warn_suspicious_bzero_size);
10425       S.Diag(DiagLoc, diag::note_suspicious_bzero_size_silence);
10426     } else if (!isLiteralZero(Call->getArg(1)->IgnoreImpCasts())) {
10427       S.Diag(DiagLoc, diag::warn_suspicious_sizeof_memset) << 0;
10428       S.Diag(DiagLoc, diag::note_suspicious_sizeof_memset_silence) << 0;
10429     }
10430     return;
10431   }
10432 
10433   // If the second argument to a memset is a sizeof expression and the third
10434   // isn't, this is also likely an error. This should catch
10435   // 'memset(buf, sizeof(buf), 0xff)'.
10436   if (BId == Builtin::BImemset &&
10437       doesExprLikelyComputeSize(Call->getArg(1)) &&
10438       !doesExprLikelyComputeSize(Call->getArg(2))) {
10439     SourceLocation DiagLoc = Call->getArg(1)->getExprLoc();
10440     S.Diag(DiagLoc, diag::warn_suspicious_sizeof_memset) << 1;
10441     S.Diag(DiagLoc, diag::note_suspicious_sizeof_memset_silence) << 1;
10442     return;
10443   }
10444 }
10445 
10446 /// Check for dangerous or invalid arguments to memset().
10447 ///
10448 /// This issues warnings on known problematic, dangerous or unspecified
10449 /// arguments to the standard 'memset', 'memcpy', 'memmove', and 'memcmp'
10450 /// function calls.
10451 ///
10452 /// \param Call The call expression to diagnose.
10453 void Sema::CheckMemaccessArguments(const CallExpr *Call,
10454                                    unsigned BId,
10455                                    IdentifierInfo *FnName) {
10456   assert(BId != 0);
10457 
10458   // It is possible to have a non-standard definition of memset.  Validate
10459   // we have enough arguments, and if not, abort further checking.
10460   unsigned ExpectedNumArgs =
10461       (BId == Builtin::BIstrndup || BId == Builtin::BIbzero ? 2 : 3);
10462   if (Call->getNumArgs() < ExpectedNumArgs)
10463     return;
10464 
10465   unsigned LastArg = (BId == Builtin::BImemset || BId == Builtin::BIbzero ||
10466                       BId == Builtin::BIstrndup ? 1 : 2);
10467   unsigned LenArg =
10468       (BId == Builtin::BIbzero || BId == Builtin::BIstrndup ? 1 : 2);
10469   const Expr *LenExpr = Call->getArg(LenArg)->IgnoreParenImpCasts();
10470 
10471   if (CheckMemorySizeofForComparison(*this, LenExpr, FnName,
10472                                      Call->getBeginLoc(), Call->getRParenLoc()))
10473     return;
10474 
10475   // Catch cases like 'memset(buf, sizeof(buf), 0)'.
10476   CheckMemaccessSize(*this, BId, Call);
10477 
10478   // We have special checking when the length is a sizeof expression.
10479   QualType SizeOfArgTy = getSizeOfArgType(LenExpr);
10480   const Expr *SizeOfArg = getSizeOfExprArg(LenExpr);
10481   llvm::FoldingSetNodeID SizeOfArgID;
10482 
10483   // Although widely used, 'bzero' is not a standard function. Be more strict
10484   // with the argument types before allowing diagnostics and only allow the
10485   // form bzero(ptr, sizeof(...)).
10486   QualType FirstArgTy = Call->getArg(0)->IgnoreParenImpCasts()->getType();
10487   if (BId == Builtin::BIbzero && !FirstArgTy->getAs<PointerType>())
10488     return;
10489 
10490   for (unsigned ArgIdx = 0; ArgIdx != LastArg; ++ArgIdx) {
10491     const Expr *Dest = Call->getArg(ArgIdx)->IgnoreParenImpCasts();
10492     SourceRange ArgRange = Call->getArg(ArgIdx)->getSourceRange();
10493 
10494     QualType DestTy = Dest->getType();
10495     QualType PointeeTy;
10496     if (const PointerType *DestPtrTy = DestTy->getAs<PointerType>()) {
10497       PointeeTy = DestPtrTy->getPointeeType();
10498 
10499       // Never warn about void type pointers. This can be used to suppress
10500       // false positives.
10501       if (PointeeTy->isVoidType())
10502         continue;
10503 
10504       // Catch "memset(p, 0, sizeof(p))" -- needs to be sizeof(*p). Do this by
10505       // actually comparing the expressions for equality. Because computing the
10506       // expression IDs can be expensive, we only do this if the diagnostic is
10507       // enabled.
10508       if (SizeOfArg &&
10509           !Diags.isIgnored(diag::warn_sizeof_pointer_expr_memaccess,
10510                            SizeOfArg->getExprLoc())) {
10511         // We only compute IDs for expressions if the warning is enabled, and
10512         // cache the sizeof arg's ID.
10513         if (SizeOfArgID == llvm::FoldingSetNodeID())
10514           SizeOfArg->Profile(SizeOfArgID, Context, true);
10515         llvm::FoldingSetNodeID DestID;
10516         Dest->Profile(DestID, Context, true);
10517         if (DestID == SizeOfArgID) {
10518           // TODO: For strncpy() and friends, this could suggest sizeof(dst)
10519           //       over sizeof(src) as well.
10520           unsigned ActionIdx = 0; // Default is to suggest dereferencing.
10521           StringRef ReadableName = FnName->getName();
10522 
10523           if (const UnaryOperator *UnaryOp = dyn_cast<UnaryOperator>(Dest))
10524             if (UnaryOp->getOpcode() == UO_AddrOf)
10525               ActionIdx = 1; // If its an address-of operator, just remove it.
10526           if (!PointeeTy->isIncompleteType() &&
10527               (Context.getTypeSize(PointeeTy) == Context.getCharWidth()))
10528             ActionIdx = 2; // If the pointee's size is sizeof(char),
10529                            // suggest an explicit length.
10530 
10531           // If the function is defined as a builtin macro, do not show macro
10532           // expansion.
10533           SourceLocation SL = SizeOfArg->getExprLoc();
10534           SourceRange DSR = Dest->getSourceRange();
10535           SourceRange SSR = SizeOfArg->getSourceRange();
10536           SourceManager &SM = getSourceManager();
10537 
10538           if (SM.isMacroArgExpansion(SL)) {
10539             ReadableName = Lexer::getImmediateMacroName(SL, SM, LangOpts);
10540             SL = SM.getSpellingLoc(SL);
10541             DSR = SourceRange(SM.getSpellingLoc(DSR.getBegin()),
10542                              SM.getSpellingLoc(DSR.getEnd()));
10543             SSR = SourceRange(SM.getSpellingLoc(SSR.getBegin()),
10544                              SM.getSpellingLoc(SSR.getEnd()));
10545           }
10546 
10547           DiagRuntimeBehavior(SL, SizeOfArg,
10548                               PDiag(diag::warn_sizeof_pointer_expr_memaccess)
10549                                 << ReadableName
10550                                 << PointeeTy
10551                                 << DestTy
10552                                 << DSR
10553                                 << SSR);
10554           DiagRuntimeBehavior(SL, SizeOfArg,
10555                          PDiag(diag::warn_sizeof_pointer_expr_memaccess_note)
10556                                 << ActionIdx
10557                                 << SSR);
10558 
10559           break;
10560         }
10561       }
10562 
10563       // Also check for cases where the sizeof argument is the exact same
10564       // type as the memory argument, and where it points to a user-defined
10565       // record type.
10566       if (SizeOfArgTy != QualType()) {
10567         if (PointeeTy->isRecordType() &&
10568             Context.typesAreCompatible(SizeOfArgTy, DestTy)) {
10569           DiagRuntimeBehavior(LenExpr->getExprLoc(), Dest,
10570                               PDiag(diag::warn_sizeof_pointer_type_memaccess)
10571                                 << FnName << SizeOfArgTy << ArgIdx
10572                                 << PointeeTy << Dest->getSourceRange()
10573                                 << LenExpr->getSourceRange());
10574           break;
10575         }
10576       }
10577     } else if (DestTy->isArrayType()) {
10578       PointeeTy = DestTy;
10579     }
10580 
10581     if (PointeeTy == QualType())
10582       continue;
10583 
10584     // Always complain about dynamic classes.
10585     bool IsContained;
10586     if (const CXXRecordDecl *ContainedRD =
10587             getContainedDynamicClass(PointeeTy, IsContained)) {
10588 
10589       unsigned OperationType = 0;
10590       const bool IsCmp = BId == Builtin::BImemcmp || BId == Builtin::BIbcmp;
10591       // "overwritten" if we're warning about the destination for any call
10592       // but memcmp; otherwise a verb appropriate to the call.
10593       if (ArgIdx != 0 || IsCmp) {
10594         if (BId == Builtin::BImemcpy)
10595           OperationType = 1;
10596         else if(BId == Builtin::BImemmove)
10597           OperationType = 2;
10598         else if (IsCmp)
10599           OperationType = 3;
10600       }
10601 
10602       DiagRuntimeBehavior(Dest->getExprLoc(), Dest,
10603                           PDiag(diag::warn_dyn_class_memaccess)
10604                               << (IsCmp ? ArgIdx + 2 : ArgIdx) << FnName
10605                               << IsContained << ContainedRD << OperationType
10606                               << Call->getCallee()->getSourceRange());
10607     } else if (PointeeTy.hasNonTrivialObjCLifetime() &&
10608              BId != Builtin::BImemset)
10609       DiagRuntimeBehavior(
10610         Dest->getExprLoc(), Dest,
10611         PDiag(diag::warn_arc_object_memaccess)
10612           << ArgIdx << FnName << PointeeTy
10613           << Call->getCallee()->getSourceRange());
10614     else if (const auto *RT = PointeeTy->getAs<RecordType>()) {
10615       if ((BId == Builtin::BImemset || BId == Builtin::BIbzero) &&
10616           RT->getDecl()->isNonTrivialToPrimitiveDefaultInitialize()) {
10617         DiagRuntimeBehavior(Dest->getExprLoc(), Dest,
10618                             PDiag(diag::warn_cstruct_memaccess)
10619                                 << ArgIdx << FnName << PointeeTy << 0);
10620         SearchNonTrivialToInitializeField::diag(PointeeTy, Dest, *this);
10621       } else if ((BId == Builtin::BImemcpy || BId == Builtin::BImemmove) &&
10622                  RT->getDecl()->isNonTrivialToPrimitiveCopy()) {
10623         DiagRuntimeBehavior(Dest->getExprLoc(), Dest,
10624                             PDiag(diag::warn_cstruct_memaccess)
10625                                 << ArgIdx << FnName << PointeeTy << 1);
10626         SearchNonTrivialToCopyField::diag(PointeeTy, Dest, *this);
10627       } else {
10628         continue;
10629       }
10630     } else
10631       continue;
10632 
10633     DiagRuntimeBehavior(
10634       Dest->getExprLoc(), Dest,
10635       PDiag(diag::note_bad_memaccess_silence)
10636         << FixItHint::CreateInsertion(ArgRange.getBegin(), "(void*)"));
10637     break;
10638   }
10639 }
10640 
10641 // A little helper routine: ignore addition and subtraction of integer literals.
10642 // This intentionally does not ignore all integer constant expressions because
10643 // we don't want to remove sizeof().
10644 static const Expr *ignoreLiteralAdditions(const Expr *Ex, ASTContext &Ctx) {
10645   Ex = Ex->IgnoreParenCasts();
10646 
10647   while (true) {
10648     const BinaryOperator * BO = dyn_cast<BinaryOperator>(Ex);
10649     if (!BO || !BO->isAdditiveOp())
10650       break;
10651 
10652     const Expr *RHS = BO->getRHS()->IgnoreParenCasts();
10653     const Expr *LHS = BO->getLHS()->IgnoreParenCasts();
10654 
10655     if (isa<IntegerLiteral>(RHS))
10656       Ex = LHS;
10657     else if (isa<IntegerLiteral>(LHS))
10658       Ex = RHS;
10659     else
10660       break;
10661   }
10662 
10663   return Ex;
10664 }
10665 
10666 static bool isConstantSizeArrayWithMoreThanOneElement(QualType Ty,
10667                                                       ASTContext &Context) {
10668   // Only handle constant-sized or VLAs, but not flexible members.
10669   if (const ConstantArrayType *CAT = Context.getAsConstantArrayType(Ty)) {
10670     // Only issue the FIXIT for arrays of size > 1.
10671     if (CAT->getSize().getSExtValue() <= 1)
10672       return false;
10673   } else if (!Ty->isVariableArrayType()) {
10674     return false;
10675   }
10676   return true;
10677 }
10678 
10679 // Warn if the user has made the 'size' argument to strlcpy or strlcat
10680 // be the size of the source, instead of the destination.
10681 void Sema::CheckStrlcpycatArguments(const CallExpr *Call,
10682                                     IdentifierInfo *FnName) {
10683 
10684   // Don't crash if the user has the wrong number of arguments
10685   unsigned NumArgs = Call->getNumArgs();
10686   if ((NumArgs != 3) && (NumArgs != 4))
10687     return;
10688 
10689   const Expr *SrcArg = ignoreLiteralAdditions(Call->getArg(1), Context);
10690   const Expr *SizeArg = ignoreLiteralAdditions(Call->getArg(2), Context);
10691   const Expr *CompareWithSrc = nullptr;
10692 
10693   if (CheckMemorySizeofForComparison(*this, SizeArg, FnName,
10694                                      Call->getBeginLoc(), Call->getRParenLoc()))
10695     return;
10696 
10697   // Look for 'strlcpy(dst, x, sizeof(x))'
10698   if (const Expr *Ex = getSizeOfExprArg(SizeArg))
10699     CompareWithSrc = Ex;
10700   else {
10701     // Look for 'strlcpy(dst, x, strlen(x))'
10702     if (const CallExpr *SizeCall = dyn_cast<CallExpr>(SizeArg)) {
10703       if (SizeCall->getBuiltinCallee() == Builtin::BIstrlen &&
10704           SizeCall->getNumArgs() == 1)
10705         CompareWithSrc = ignoreLiteralAdditions(SizeCall->getArg(0), Context);
10706     }
10707   }
10708 
10709   if (!CompareWithSrc)
10710     return;
10711 
10712   // Determine if the argument to sizeof/strlen is equal to the source
10713   // argument.  In principle there's all kinds of things you could do
10714   // here, for instance creating an == expression and evaluating it with
10715   // EvaluateAsBooleanCondition, but this uses a more direct technique:
10716   const DeclRefExpr *SrcArgDRE = dyn_cast<DeclRefExpr>(SrcArg);
10717   if (!SrcArgDRE)
10718     return;
10719 
10720   const DeclRefExpr *CompareWithSrcDRE = dyn_cast<DeclRefExpr>(CompareWithSrc);
10721   if (!CompareWithSrcDRE ||
10722       SrcArgDRE->getDecl() != CompareWithSrcDRE->getDecl())
10723     return;
10724 
10725   const Expr *OriginalSizeArg = Call->getArg(2);
10726   Diag(CompareWithSrcDRE->getBeginLoc(), diag::warn_strlcpycat_wrong_size)
10727       << OriginalSizeArg->getSourceRange() << FnName;
10728 
10729   // Output a FIXIT hint if the destination is an array (rather than a
10730   // pointer to an array).  This could be enhanced to handle some
10731   // pointers if we know the actual size, like if DstArg is 'array+2'
10732   // we could say 'sizeof(array)-2'.
10733   const Expr *DstArg = Call->getArg(0)->IgnoreParenImpCasts();
10734   if (!isConstantSizeArrayWithMoreThanOneElement(DstArg->getType(), Context))
10735     return;
10736 
10737   SmallString<128> sizeString;
10738   llvm::raw_svector_ostream OS(sizeString);
10739   OS << "sizeof(";
10740   DstArg->printPretty(OS, nullptr, getPrintingPolicy());
10741   OS << ")";
10742 
10743   Diag(OriginalSizeArg->getBeginLoc(), diag::note_strlcpycat_wrong_size)
10744       << FixItHint::CreateReplacement(OriginalSizeArg->getSourceRange(),
10745                                       OS.str());
10746 }
10747 
10748 /// Check if two expressions refer to the same declaration.
10749 static bool referToTheSameDecl(const Expr *E1, const Expr *E2) {
10750   if (const DeclRefExpr *D1 = dyn_cast_or_null<DeclRefExpr>(E1))
10751     if (const DeclRefExpr *D2 = dyn_cast_or_null<DeclRefExpr>(E2))
10752       return D1->getDecl() == D2->getDecl();
10753   return false;
10754 }
10755 
10756 static const Expr *getStrlenExprArg(const Expr *E) {
10757   if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
10758     const FunctionDecl *FD = CE->getDirectCallee();
10759     if (!FD || FD->getMemoryFunctionKind() != Builtin::BIstrlen)
10760       return nullptr;
10761     return CE->getArg(0)->IgnoreParenCasts();
10762   }
10763   return nullptr;
10764 }
10765 
10766 // Warn on anti-patterns as the 'size' argument to strncat.
10767 // The correct size argument should look like following:
10768 //   strncat(dst, src, sizeof(dst) - strlen(dest) - 1);
10769 void Sema::CheckStrncatArguments(const CallExpr *CE,
10770                                  IdentifierInfo *FnName) {
10771   // Don't crash if the user has the wrong number of arguments.
10772   if (CE->getNumArgs() < 3)
10773     return;
10774   const Expr *DstArg = CE->getArg(0)->IgnoreParenCasts();
10775   const Expr *SrcArg = CE->getArg(1)->IgnoreParenCasts();
10776   const Expr *LenArg = CE->getArg(2)->IgnoreParenCasts();
10777 
10778   if (CheckMemorySizeofForComparison(*this, LenArg, FnName, CE->getBeginLoc(),
10779                                      CE->getRParenLoc()))
10780     return;
10781 
10782   // Identify common expressions, which are wrongly used as the size argument
10783   // to strncat and may lead to buffer overflows.
10784   unsigned PatternType = 0;
10785   if (const Expr *SizeOfArg = getSizeOfExprArg(LenArg)) {
10786     // - sizeof(dst)
10787     if (referToTheSameDecl(SizeOfArg, DstArg))
10788       PatternType = 1;
10789     // - sizeof(src)
10790     else if (referToTheSameDecl(SizeOfArg, SrcArg))
10791       PatternType = 2;
10792   } else if (const BinaryOperator *BE = dyn_cast<BinaryOperator>(LenArg)) {
10793     if (BE->getOpcode() == BO_Sub) {
10794       const Expr *L = BE->getLHS()->IgnoreParenCasts();
10795       const Expr *R = BE->getRHS()->IgnoreParenCasts();
10796       // - sizeof(dst) - strlen(dst)
10797       if (referToTheSameDecl(DstArg, getSizeOfExprArg(L)) &&
10798           referToTheSameDecl(DstArg, getStrlenExprArg(R)))
10799         PatternType = 1;
10800       // - sizeof(src) - (anything)
10801       else if (referToTheSameDecl(SrcArg, getSizeOfExprArg(L)))
10802         PatternType = 2;
10803     }
10804   }
10805 
10806   if (PatternType == 0)
10807     return;
10808 
10809   // Generate the diagnostic.
10810   SourceLocation SL = LenArg->getBeginLoc();
10811   SourceRange SR = LenArg->getSourceRange();
10812   SourceManager &SM = getSourceManager();
10813 
10814   // If the function is defined as a builtin macro, do not show macro expansion.
10815   if (SM.isMacroArgExpansion(SL)) {
10816     SL = SM.getSpellingLoc(SL);
10817     SR = SourceRange(SM.getSpellingLoc(SR.getBegin()),
10818                      SM.getSpellingLoc(SR.getEnd()));
10819   }
10820 
10821   // Check if the destination is an array (rather than a pointer to an array).
10822   QualType DstTy = DstArg->getType();
10823   bool isKnownSizeArray = isConstantSizeArrayWithMoreThanOneElement(DstTy,
10824                                                                     Context);
10825   if (!isKnownSizeArray) {
10826     if (PatternType == 1)
10827       Diag(SL, diag::warn_strncat_wrong_size) << SR;
10828     else
10829       Diag(SL, diag::warn_strncat_src_size) << SR;
10830     return;
10831   }
10832 
10833   if (PatternType == 1)
10834     Diag(SL, diag::warn_strncat_large_size) << SR;
10835   else
10836     Diag(SL, diag::warn_strncat_src_size) << SR;
10837 
10838   SmallString<128> sizeString;
10839   llvm::raw_svector_ostream OS(sizeString);
10840   OS << "sizeof(";
10841   DstArg->printPretty(OS, nullptr, getPrintingPolicy());
10842   OS << ") - ";
10843   OS << "strlen(";
10844   DstArg->printPretty(OS, nullptr, getPrintingPolicy());
10845   OS << ") - 1";
10846 
10847   Diag(SL, diag::note_strncat_wrong_size)
10848     << FixItHint::CreateReplacement(SR, OS.str());
10849 }
10850 
10851 namespace {
10852 void CheckFreeArgumentsOnLvalue(Sema &S, const std::string &CalleeName,
10853                                 const UnaryOperator *UnaryExpr, const Decl *D) {
10854   if (isa<FieldDecl, FunctionDecl, VarDecl>(D)) {
10855     S.Diag(UnaryExpr->getBeginLoc(), diag::warn_free_nonheap_object)
10856         << CalleeName << 0 /*object: */ << cast<NamedDecl>(D);
10857     return;
10858   }
10859 }
10860 
10861 void CheckFreeArgumentsAddressof(Sema &S, const std::string &CalleeName,
10862                                  const UnaryOperator *UnaryExpr) {
10863   if (const auto *Lvalue = dyn_cast<DeclRefExpr>(UnaryExpr->getSubExpr())) {
10864     const Decl *D = Lvalue->getDecl();
10865     if (isa<DeclaratorDecl>(D))
10866       if (!dyn_cast<DeclaratorDecl>(D)->getType()->isReferenceType())
10867         return CheckFreeArgumentsOnLvalue(S, CalleeName, UnaryExpr, D);
10868   }
10869 
10870   if (const auto *Lvalue = dyn_cast<MemberExpr>(UnaryExpr->getSubExpr()))
10871     return CheckFreeArgumentsOnLvalue(S, CalleeName, UnaryExpr,
10872                                       Lvalue->getMemberDecl());
10873 }
10874 
10875 void CheckFreeArgumentsPlus(Sema &S, const std::string &CalleeName,
10876                             const UnaryOperator *UnaryExpr) {
10877   const auto *Lambda = dyn_cast<LambdaExpr>(
10878       UnaryExpr->getSubExpr()->IgnoreImplicitAsWritten()->IgnoreParens());
10879   if (!Lambda)
10880     return;
10881 
10882   S.Diag(Lambda->getBeginLoc(), diag::warn_free_nonheap_object)
10883       << CalleeName << 2 /*object: lambda expression*/;
10884 }
10885 
10886 void CheckFreeArgumentsStackArray(Sema &S, const std::string &CalleeName,
10887                                   const DeclRefExpr *Lvalue) {
10888   const auto *Var = dyn_cast<VarDecl>(Lvalue->getDecl());
10889   if (Var == nullptr)
10890     return;
10891 
10892   S.Diag(Lvalue->getBeginLoc(), diag::warn_free_nonheap_object)
10893       << CalleeName << 0 /*object: */ << Var;
10894 }
10895 
10896 void CheckFreeArgumentsCast(Sema &S, const std::string &CalleeName,
10897                             const CastExpr *Cast) {
10898   SmallString<128> SizeString;
10899   llvm::raw_svector_ostream OS(SizeString);
10900 
10901   clang::CastKind Kind = Cast->getCastKind();
10902   if (Kind == clang::CK_BitCast &&
10903       !Cast->getSubExpr()->getType()->isFunctionPointerType())
10904     return;
10905   if (Kind == clang::CK_IntegralToPointer &&
10906       !isa<IntegerLiteral>(
10907           Cast->getSubExpr()->IgnoreParenImpCasts()->IgnoreParens()))
10908     return;
10909 
10910   switch (Cast->getCastKind()) {
10911   case clang::CK_BitCast:
10912   case clang::CK_IntegralToPointer:
10913   case clang::CK_FunctionToPointerDecay:
10914     OS << '\'';
10915     Cast->printPretty(OS, nullptr, S.getPrintingPolicy());
10916     OS << '\'';
10917     break;
10918   default:
10919     return;
10920   }
10921 
10922   S.Diag(Cast->getBeginLoc(), diag::warn_free_nonheap_object)
10923       << CalleeName << 0 /*object: */ << OS.str();
10924 }
10925 } // namespace
10926 
10927 /// Alerts the user that they are attempting to free a non-malloc'd object.
10928 void Sema::CheckFreeArguments(const CallExpr *E) {
10929   const std::string CalleeName =
10930       dyn_cast<FunctionDecl>(E->getCalleeDecl())->getQualifiedNameAsString();
10931 
10932   { // Prefer something that doesn't involve a cast to make things simpler.
10933     const Expr *Arg = E->getArg(0)->IgnoreParenCasts();
10934     if (const auto *UnaryExpr = dyn_cast<UnaryOperator>(Arg))
10935       switch (UnaryExpr->getOpcode()) {
10936       case UnaryOperator::Opcode::UO_AddrOf:
10937         return CheckFreeArgumentsAddressof(*this, CalleeName, UnaryExpr);
10938       case UnaryOperator::Opcode::UO_Plus:
10939         return CheckFreeArgumentsPlus(*this, CalleeName, UnaryExpr);
10940       default:
10941         break;
10942       }
10943 
10944     if (const auto *Lvalue = dyn_cast<DeclRefExpr>(Arg))
10945       if (Lvalue->getType()->isArrayType())
10946         return CheckFreeArgumentsStackArray(*this, CalleeName, Lvalue);
10947 
10948     if (const auto *Label = dyn_cast<AddrLabelExpr>(Arg)) {
10949       Diag(Label->getBeginLoc(), diag::warn_free_nonheap_object)
10950           << CalleeName << 0 /*object: */ << Label->getLabel()->getIdentifier();
10951       return;
10952     }
10953 
10954     if (isa<BlockExpr>(Arg)) {
10955       Diag(Arg->getBeginLoc(), diag::warn_free_nonheap_object)
10956           << CalleeName << 1 /*object: block*/;
10957       return;
10958     }
10959   }
10960   // Maybe the cast was important, check after the other cases.
10961   if (const auto *Cast = dyn_cast<CastExpr>(E->getArg(0)))
10962     return CheckFreeArgumentsCast(*this, CalleeName, Cast);
10963 }
10964 
10965 void
10966 Sema::CheckReturnValExpr(Expr *RetValExp, QualType lhsType,
10967                          SourceLocation ReturnLoc,
10968                          bool isObjCMethod,
10969                          const AttrVec *Attrs,
10970                          const FunctionDecl *FD) {
10971   // Check if the return value is null but should not be.
10972   if (((Attrs && hasSpecificAttr<ReturnsNonNullAttr>(*Attrs)) ||
10973        (!isObjCMethod && isNonNullType(Context, lhsType))) &&
10974       CheckNonNullExpr(*this, RetValExp))
10975     Diag(ReturnLoc, diag::warn_null_ret)
10976       << (isObjCMethod ? 1 : 0) << RetValExp->getSourceRange();
10977 
10978   // C++11 [basic.stc.dynamic.allocation]p4:
10979   //   If an allocation function declared with a non-throwing
10980   //   exception-specification fails to allocate storage, it shall return
10981   //   a null pointer. Any other allocation function that fails to allocate
10982   //   storage shall indicate failure only by throwing an exception [...]
10983   if (FD) {
10984     OverloadedOperatorKind Op = FD->getOverloadedOperator();
10985     if (Op == OO_New || Op == OO_Array_New) {
10986       const FunctionProtoType *Proto
10987         = FD->getType()->castAs<FunctionProtoType>();
10988       if (!Proto->isNothrow(/*ResultIfDependent*/true) &&
10989           CheckNonNullExpr(*this, RetValExp))
10990         Diag(ReturnLoc, diag::warn_operator_new_returns_null)
10991           << FD << getLangOpts().CPlusPlus11;
10992     }
10993   }
10994 
10995   // PPC MMA non-pointer types are not allowed as return type. Checking the type
10996   // here prevent the user from using a PPC MMA type as trailing return type.
10997   if (Context.getTargetInfo().getTriple().isPPC64())
10998     CheckPPCMMAType(RetValExp->getType(), ReturnLoc);
10999 }
11000 
11001 //===--- CHECK: Floating-Point comparisons (-Wfloat-equal) ---------------===//
11002 
11003 /// Check for comparisons of floating point operands using != and ==.
11004 /// Issue a warning if these are no self-comparisons, as they are not likely
11005 /// to do what the programmer intended.
11006 void Sema::CheckFloatComparison(SourceLocation Loc, Expr* LHS, Expr *RHS) {
11007   Expr* LeftExprSansParen = LHS->IgnoreParenImpCasts();
11008   Expr* RightExprSansParen = RHS->IgnoreParenImpCasts();
11009 
11010   // Special case: check for x == x (which is OK).
11011   // Do not emit warnings for such cases.
11012   if (DeclRefExpr* DRL = dyn_cast<DeclRefExpr>(LeftExprSansParen))
11013     if (DeclRefExpr* DRR = dyn_cast<DeclRefExpr>(RightExprSansParen))
11014       if (DRL->getDecl() == DRR->getDecl())
11015         return;
11016 
11017   // Special case: check for comparisons against literals that can be exactly
11018   //  represented by APFloat.  In such cases, do not emit a warning.  This
11019   //  is a heuristic: often comparison against such literals are used to
11020   //  detect if a value in a variable has not changed.  This clearly can
11021   //  lead to false negatives.
11022   if (FloatingLiteral* FLL = dyn_cast<FloatingLiteral>(LeftExprSansParen)) {
11023     if (FLL->isExact())
11024       return;
11025   } else
11026     if (FloatingLiteral* FLR = dyn_cast<FloatingLiteral>(RightExprSansParen))
11027       if (FLR->isExact())
11028         return;
11029 
11030   // Check for comparisons with builtin types.
11031   if (CallExpr* CL = dyn_cast<CallExpr>(LeftExprSansParen))
11032     if (CL->getBuiltinCallee())
11033       return;
11034 
11035   if (CallExpr* CR = dyn_cast<CallExpr>(RightExprSansParen))
11036     if (CR->getBuiltinCallee())
11037       return;
11038 
11039   // Emit the diagnostic.
11040   Diag(Loc, diag::warn_floatingpoint_eq)
11041     << LHS->getSourceRange() << RHS->getSourceRange();
11042 }
11043 
11044 //===--- CHECK: Integer mixed-sign comparisons (-Wsign-compare) --------===//
11045 //===--- CHECK: Lossy implicit conversions (-Wconversion) --------------===//
11046 
11047 namespace {
11048 
11049 /// Structure recording the 'active' range of an integer-valued
11050 /// expression.
11051 struct IntRange {
11052   /// The number of bits active in the int. Note that this includes exactly one
11053   /// sign bit if !NonNegative.
11054   unsigned Width;
11055 
11056   /// True if the int is known not to have negative values. If so, all leading
11057   /// bits before Width are known zero, otherwise they are known to be the
11058   /// same as the MSB within Width.
11059   bool NonNegative;
11060 
11061   IntRange(unsigned Width, bool NonNegative)
11062       : Width(Width), NonNegative(NonNegative) {}
11063 
11064   /// Number of bits excluding the sign bit.
11065   unsigned valueBits() const {
11066     return NonNegative ? Width : Width - 1;
11067   }
11068 
11069   /// Returns the range of the bool type.
11070   static IntRange forBoolType() {
11071     return IntRange(1, true);
11072   }
11073 
11074   /// Returns the range of an opaque value of the given integral type.
11075   static IntRange forValueOfType(ASTContext &C, QualType T) {
11076     return forValueOfCanonicalType(C,
11077                           T->getCanonicalTypeInternal().getTypePtr());
11078   }
11079 
11080   /// Returns the range of an opaque value of a canonical integral type.
11081   static IntRange forValueOfCanonicalType(ASTContext &C, const Type *T) {
11082     assert(T->isCanonicalUnqualified());
11083 
11084     if (const VectorType *VT = dyn_cast<VectorType>(T))
11085       T = VT->getElementType().getTypePtr();
11086     if (const ComplexType *CT = dyn_cast<ComplexType>(T))
11087       T = CT->getElementType().getTypePtr();
11088     if (const AtomicType *AT = dyn_cast<AtomicType>(T))
11089       T = AT->getValueType().getTypePtr();
11090 
11091     if (!C.getLangOpts().CPlusPlus) {
11092       // For enum types in C code, use the underlying datatype.
11093       if (const EnumType *ET = dyn_cast<EnumType>(T))
11094         T = ET->getDecl()->getIntegerType().getDesugaredType(C).getTypePtr();
11095     } else if (const EnumType *ET = dyn_cast<EnumType>(T)) {
11096       // For enum types in C++, use the known bit width of the enumerators.
11097       EnumDecl *Enum = ET->getDecl();
11098       // In C++11, enums can have a fixed underlying type. Use this type to
11099       // compute the range.
11100       if (Enum->isFixed()) {
11101         return IntRange(C.getIntWidth(QualType(T, 0)),
11102                         !ET->isSignedIntegerOrEnumerationType());
11103       }
11104 
11105       unsigned NumPositive = Enum->getNumPositiveBits();
11106       unsigned NumNegative = Enum->getNumNegativeBits();
11107 
11108       if (NumNegative == 0)
11109         return IntRange(NumPositive, true/*NonNegative*/);
11110       else
11111         return IntRange(std::max(NumPositive + 1, NumNegative),
11112                         false/*NonNegative*/);
11113     }
11114 
11115     if (const auto *EIT = dyn_cast<ExtIntType>(T))
11116       return IntRange(EIT->getNumBits(), EIT->isUnsigned());
11117 
11118     const BuiltinType *BT = cast<BuiltinType>(T);
11119     assert(BT->isInteger());
11120 
11121     return IntRange(C.getIntWidth(QualType(T, 0)), BT->isUnsignedInteger());
11122   }
11123 
11124   /// Returns the "target" range of a canonical integral type, i.e.
11125   /// the range of values expressible in the type.
11126   ///
11127   /// This matches forValueOfCanonicalType except that enums have the
11128   /// full range of their type, not the range of their enumerators.
11129   static IntRange forTargetOfCanonicalType(ASTContext &C, const Type *T) {
11130     assert(T->isCanonicalUnqualified());
11131 
11132     if (const VectorType *VT = dyn_cast<VectorType>(T))
11133       T = VT->getElementType().getTypePtr();
11134     if (const ComplexType *CT = dyn_cast<ComplexType>(T))
11135       T = CT->getElementType().getTypePtr();
11136     if (const AtomicType *AT = dyn_cast<AtomicType>(T))
11137       T = AT->getValueType().getTypePtr();
11138     if (const EnumType *ET = dyn_cast<EnumType>(T))
11139       T = C.getCanonicalType(ET->getDecl()->getIntegerType()).getTypePtr();
11140 
11141     if (const auto *EIT = dyn_cast<ExtIntType>(T))
11142       return IntRange(EIT->getNumBits(), EIT->isUnsigned());
11143 
11144     const BuiltinType *BT = cast<BuiltinType>(T);
11145     assert(BT->isInteger());
11146 
11147     return IntRange(C.getIntWidth(QualType(T, 0)), BT->isUnsignedInteger());
11148   }
11149 
11150   /// Returns the supremum of two ranges: i.e. their conservative merge.
11151   static IntRange join(IntRange L, IntRange R) {
11152     bool Unsigned = L.NonNegative && R.NonNegative;
11153     return IntRange(std::max(L.valueBits(), R.valueBits()) + !Unsigned,
11154                     L.NonNegative && R.NonNegative);
11155   }
11156 
11157   /// Return the range of a bitwise-AND of the two ranges.
11158   static IntRange bit_and(IntRange L, IntRange R) {
11159     unsigned Bits = std::max(L.Width, R.Width);
11160     bool NonNegative = false;
11161     if (L.NonNegative) {
11162       Bits = std::min(Bits, L.Width);
11163       NonNegative = true;
11164     }
11165     if (R.NonNegative) {
11166       Bits = std::min(Bits, R.Width);
11167       NonNegative = true;
11168     }
11169     return IntRange(Bits, NonNegative);
11170   }
11171 
11172   /// Return the range of a sum of the two ranges.
11173   static IntRange sum(IntRange L, IntRange R) {
11174     bool Unsigned = L.NonNegative && R.NonNegative;
11175     return IntRange(std::max(L.valueBits(), R.valueBits()) + 1 + !Unsigned,
11176                     Unsigned);
11177   }
11178 
11179   /// Return the range of a difference of the two ranges.
11180   static IntRange difference(IntRange L, IntRange R) {
11181     // We need a 1-bit-wider range if:
11182     //   1) LHS can be negative: least value can be reduced.
11183     //   2) RHS can be negative: greatest value can be increased.
11184     bool CanWiden = !L.NonNegative || !R.NonNegative;
11185     bool Unsigned = L.NonNegative && R.Width == 0;
11186     return IntRange(std::max(L.valueBits(), R.valueBits()) + CanWiden +
11187                         !Unsigned,
11188                     Unsigned);
11189   }
11190 
11191   /// Return the range of a product of the two ranges.
11192   static IntRange product(IntRange L, IntRange R) {
11193     // If both LHS and RHS can be negative, we can form
11194     //   -2^L * -2^R = 2^(L + R)
11195     // which requires L + R + 1 value bits to represent.
11196     bool CanWiden = !L.NonNegative && !R.NonNegative;
11197     bool Unsigned = L.NonNegative && R.NonNegative;
11198     return IntRange(L.valueBits() + R.valueBits() + CanWiden + !Unsigned,
11199                     Unsigned);
11200   }
11201 
11202   /// Return the range of a remainder operation between the two ranges.
11203   static IntRange rem(IntRange L, IntRange R) {
11204     // The result of a remainder can't be larger than the result of
11205     // either side. The sign of the result is the sign of the LHS.
11206     bool Unsigned = L.NonNegative;
11207     return IntRange(std::min(L.valueBits(), R.valueBits()) + !Unsigned,
11208                     Unsigned);
11209   }
11210 };
11211 
11212 } // namespace
11213 
11214 static IntRange GetValueRange(ASTContext &C, llvm::APSInt &value,
11215                               unsigned MaxWidth) {
11216   if (value.isSigned() && value.isNegative())
11217     return IntRange(value.getMinSignedBits(), false);
11218 
11219   if (value.getBitWidth() > MaxWidth)
11220     value = value.trunc(MaxWidth);
11221 
11222   // isNonNegative() just checks the sign bit without considering
11223   // signedness.
11224   return IntRange(value.getActiveBits(), true);
11225 }
11226 
11227 static IntRange GetValueRange(ASTContext &C, APValue &result, QualType Ty,
11228                               unsigned MaxWidth) {
11229   if (result.isInt())
11230     return GetValueRange(C, result.getInt(), MaxWidth);
11231 
11232   if (result.isVector()) {
11233     IntRange R = GetValueRange(C, result.getVectorElt(0), Ty, MaxWidth);
11234     for (unsigned i = 1, e = result.getVectorLength(); i != e; ++i) {
11235       IntRange El = GetValueRange(C, result.getVectorElt(i), Ty, MaxWidth);
11236       R = IntRange::join(R, El);
11237     }
11238     return R;
11239   }
11240 
11241   if (result.isComplexInt()) {
11242     IntRange R = GetValueRange(C, result.getComplexIntReal(), MaxWidth);
11243     IntRange I = GetValueRange(C, result.getComplexIntImag(), MaxWidth);
11244     return IntRange::join(R, I);
11245   }
11246 
11247   // This can happen with lossless casts to intptr_t of "based" lvalues.
11248   // Assume it might use arbitrary bits.
11249   // FIXME: The only reason we need to pass the type in here is to get
11250   // the sign right on this one case.  It would be nice if APValue
11251   // preserved this.
11252   assert(result.isLValue() || result.isAddrLabelDiff());
11253   return IntRange(MaxWidth, Ty->isUnsignedIntegerOrEnumerationType());
11254 }
11255 
11256 static QualType GetExprType(const Expr *E) {
11257   QualType Ty = E->getType();
11258   if (const AtomicType *AtomicRHS = Ty->getAs<AtomicType>())
11259     Ty = AtomicRHS->getValueType();
11260   return Ty;
11261 }
11262 
11263 /// Pseudo-evaluate the given integer expression, estimating the
11264 /// range of values it might take.
11265 ///
11266 /// \param MaxWidth The width to which the value will be truncated.
11267 /// \param Approximate If \c true, return a likely range for the result: in
11268 ///        particular, assume that aritmetic on narrower types doesn't leave
11269 ///        those types. If \c false, return a range including all possible
11270 ///        result values.
11271 static IntRange GetExprRange(ASTContext &C, const Expr *E, unsigned MaxWidth,
11272                              bool InConstantContext, bool Approximate) {
11273   E = E->IgnoreParens();
11274 
11275   // Try a full evaluation first.
11276   Expr::EvalResult result;
11277   if (E->EvaluateAsRValue(result, C, InConstantContext))
11278     return GetValueRange(C, result.Val, GetExprType(E), MaxWidth);
11279 
11280   // I think we only want to look through implicit casts here; if the
11281   // user has an explicit widening cast, we should treat the value as
11282   // being of the new, wider type.
11283   if (const auto *CE = dyn_cast<ImplicitCastExpr>(E)) {
11284     if (CE->getCastKind() == CK_NoOp || CE->getCastKind() == CK_LValueToRValue)
11285       return GetExprRange(C, CE->getSubExpr(), MaxWidth, InConstantContext,
11286                           Approximate);
11287 
11288     IntRange OutputTypeRange = IntRange::forValueOfType(C, GetExprType(CE));
11289 
11290     bool isIntegerCast = CE->getCastKind() == CK_IntegralCast ||
11291                          CE->getCastKind() == CK_BooleanToSignedIntegral;
11292 
11293     // Assume that non-integer casts can span the full range of the type.
11294     if (!isIntegerCast)
11295       return OutputTypeRange;
11296 
11297     IntRange SubRange = GetExprRange(C, CE->getSubExpr(),
11298                                      std::min(MaxWidth, OutputTypeRange.Width),
11299                                      InConstantContext, Approximate);
11300 
11301     // Bail out if the subexpr's range is as wide as the cast type.
11302     if (SubRange.Width >= OutputTypeRange.Width)
11303       return OutputTypeRange;
11304 
11305     // Otherwise, we take the smaller width, and we're non-negative if
11306     // either the output type or the subexpr is.
11307     return IntRange(SubRange.Width,
11308                     SubRange.NonNegative || OutputTypeRange.NonNegative);
11309   }
11310 
11311   if (const auto *CO = dyn_cast<ConditionalOperator>(E)) {
11312     // If we can fold the condition, just take that operand.
11313     bool CondResult;
11314     if (CO->getCond()->EvaluateAsBooleanCondition(CondResult, C))
11315       return GetExprRange(C,
11316                           CondResult ? CO->getTrueExpr() : CO->getFalseExpr(),
11317                           MaxWidth, InConstantContext, Approximate);
11318 
11319     // Otherwise, conservatively merge.
11320     // GetExprRange requires an integer expression, but a throw expression
11321     // results in a void type.
11322     Expr *E = CO->getTrueExpr();
11323     IntRange L = E->getType()->isVoidType()
11324                      ? IntRange{0, true}
11325                      : GetExprRange(C, E, MaxWidth, InConstantContext, Approximate);
11326     E = CO->getFalseExpr();
11327     IntRange R = E->getType()->isVoidType()
11328                      ? IntRange{0, true}
11329                      : GetExprRange(C, E, MaxWidth, InConstantContext, Approximate);
11330     return IntRange::join(L, R);
11331   }
11332 
11333   if (const auto *BO = dyn_cast<BinaryOperator>(E)) {
11334     IntRange (*Combine)(IntRange, IntRange) = IntRange::join;
11335 
11336     switch (BO->getOpcode()) {
11337     case BO_Cmp:
11338       llvm_unreachable("builtin <=> should have class type");
11339 
11340     // Boolean-valued operations are single-bit and positive.
11341     case BO_LAnd:
11342     case BO_LOr:
11343     case BO_LT:
11344     case BO_GT:
11345     case BO_LE:
11346     case BO_GE:
11347     case BO_EQ:
11348     case BO_NE:
11349       return IntRange::forBoolType();
11350 
11351     // The type of the assignments is the type of the LHS, so the RHS
11352     // is not necessarily the same type.
11353     case BO_MulAssign:
11354     case BO_DivAssign:
11355     case BO_RemAssign:
11356     case BO_AddAssign:
11357     case BO_SubAssign:
11358     case BO_XorAssign:
11359     case BO_OrAssign:
11360       // TODO: bitfields?
11361       return IntRange::forValueOfType(C, GetExprType(E));
11362 
11363     // Simple assignments just pass through the RHS, which will have
11364     // been coerced to the LHS type.
11365     case BO_Assign:
11366       // TODO: bitfields?
11367       return GetExprRange(C, BO->getRHS(), MaxWidth, InConstantContext,
11368                           Approximate);
11369 
11370     // Operations with opaque sources are black-listed.
11371     case BO_PtrMemD:
11372     case BO_PtrMemI:
11373       return IntRange::forValueOfType(C, GetExprType(E));
11374 
11375     // Bitwise-and uses the *infinum* of the two source ranges.
11376     case BO_And:
11377     case BO_AndAssign:
11378       Combine = IntRange::bit_and;
11379       break;
11380 
11381     // Left shift gets black-listed based on a judgement call.
11382     case BO_Shl:
11383       // ...except that we want to treat '1 << (blah)' as logically
11384       // positive.  It's an important idiom.
11385       if (IntegerLiteral *I
11386             = dyn_cast<IntegerLiteral>(BO->getLHS()->IgnoreParenCasts())) {
11387         if (I->getValue() == 1) {
11388           IntRange R = IntRange::forValueOfType(C, GetExprType(E));
11389           return IntRange(R.Width, /*NonNegative*/ true);
11390         }
11391       }
11392       LLVM_FALLTHROUGH;
11393 
11394     case BO_ShlAssign:
11395       return IntRange::forValueOfType(C, GetExprType(E));
11396 
11397     // Right shift by a constant can narrow its left argument.
11398     case BO_Shr:
11399     case BO_ShrAssign: {
11400       IntRange L = GetExprRange(C, BO->getLHS(), MaxWidth, InConstantContext,
11401                                 Approximate);
11402 
11403       // If the shift amount is a positive constant, drop the width by
11404       // that much.
11405       if (Optional<llvm::APSInt> shift =
11406               BO->getRHS()->getIntegerConstantExpr(C)) {
11407         if (shift->isNonNegative()) {
11408           unsigned zext = shift->getZExtValue();
11409           if (zext >= L.Width)
11410             L.Width = (L.NonNegative ? 0 : 1);
11411           else
11412             L.Width -= zext;
11413         }
11414       }
11415 
11416       return L;
11417     }
11418 
11419     // Comma acts as its right operand.
11420     case BO_Comma:
11421       return GetExprRange(C, BO->getRHS(), MaxWidth, InConstantContext,
11422                           Approximate);
11423 
11424     case BO_Add:
11425       if (!Approximate)
11426         Combine = IntRange::sum;
11427       break;
11428 
11429     case BO_Sub:
11430       if (BO->getLHS()->getType()->isPointerType())
11431         return IntRange::forValueOfType(C, GetExprType(E));
11432       if (!Approximate)
11433         Combine = IntRange::difference;
11434       break;
11435 
11436     case BO_Mul:
11437       if (!Approximate)
11438         Combine = IntRange::product;
11439       break;
11440 
11441     // The width of a division result is mostly determined by the size
11442     // of the LHS.
11443     case BO_Div: {
11444       // Don't 'pre-truncate' the operands.
11445       unsigned opWidth = C.getIntWidth(GetExprType(E));
11446       IntRange L = GetExprRange(C, BO->getLHS(), opWidth, InConstantContext,
11447                                 Approximate);
11448 
11449       // If the divisor is constant, use that.
11450       if (Optional<llvm::APSInt> divisor =
11451               BO->getRHS()->getIntegerConstantExpr(C)) {
11452         unsigned log2 = divisor->logBase2(); // floor(log_2(divisor))
11453         if (log2 >= L.Width)
11454           L.Width = (L.NonNegative ? 0 : 1);
11455         else
11456           L.Width = std::min(L.Width - log2, MaxWidth);
11457         return L;
11458       }
11459 
11460       // Otherwise, just use the LHS's width.
11461       // FIXME: This is wrong if the LHS could be its minimal value and the RHS
11462       // could be -1.
11463       IntRange R = GetExprRange(C, BO->getRHS(), opWidth, InConstantContext,
11464                                 Approximate);
11465       return IntRange(L.Width, L.NonNegative && R.NonNegative);
11466     }
11467 
11468     case BO_Rem:
11469       Combine = IntRange::rem;
11470       break;
11471 
11472     // The default behavior is okay for these.
11473     case BO_Xor:
11474     case BO_Or:
11475       break;
11476     }
11477 
11478     // Combine the two ranges, but limit the result to the type in which we
11479     // performed the computation.
11480     QualType T = GetExprType(E);
11481     unsigned opWidth = C.getIntWidth(T);
11482     IntRange L =
11483         GetExprRange(C, BO->getLHS(), opWidth, InConstantContext, Approximate);
11484     IntRange R =
11485         GetExprRange(C, BO->getRHS(), opWidth, InConstantContext, Approximate);
11486     IntRange C = Combine(L, R);
11487     C.NonNegative |= T->isUnsignedIntegerOrEnumerationType();
11488     C.Width = std::min(C.Width, MaxWidth);
11489     return C;
11490   }
11491 
11492   if (const auto *UO = dyn_cast<UnaryOperator>(E)) {
11493     switch (UO->getOpcode()) {
11494     // Boolean-valued operations are white-listed.
11495     case UO_LNot:
11496       return IntRange::forBoolType();
11497 
11498     // Operations with opaque sources are black-listed.
11499     case UO_Deref:
11500     case UO_AddrOf: // should be impossible
11501       return IntRange::forValueOfType(C, GetExprType(E));
11502 
11503     default:
11504       return GetExprRange(C, UO->getSubExpr(), MaxWidth, InConstantContext,
11505                           Approximate);
11506     }
11507   }
11508 
11509   if (const auto *OVE = dyn_cast<OpaqueValueExpr>(E))
11510     return GetExprRange(C, OVE->getSourceExpr(), MaxWidth, InConstantContext,
11511                         Approximate);
11512 
11513   if (const auto *BitField = E->getSourceBitField())
11514     return IntRange(BitField->getBitWidthValue(C),
11515                     BitField->getType()->isUnsignedIntegerOrEnumerationType());
11516 
11517   return IntRange::forValueOfType(C, GetExprType(E));
11518 }
11519 
11520 static IntRange GetExprRange(ASTContext &C, const Expr *E,
11521                              bool InConstantContext, bool Approximate) {
11522   return GetExprRange(C, E, C.getIntWidth(GetExprType(E)), InConstantContext,
11523                       Approximate);
11524 }
11525 
11526 /// Checks whether the given value, which currently has the given
11527 /// source semantics, has the same value when coerced through the
11528 /// target semantics.
11529 static bool IsSameFloatAfterCast(const llvm::APFloat &value,
11530                                  const llvm::fltSemantics &Src,
11531                                  const llvm::fltSemantics &Tgt) {
11532   llvm::APFloat truncated = value;
11533 
11534   bool ignored;
11535   truncated.convert(Src, llvm::APFloat::rmNearestTiesToEven, &ignored);
11536   truncated.convert(Tgt, llvm::APFloat::rmNearestTiesToEven, &ignored);
11537 
11538   return truncated.bitwiseIsEqual(value);
11539 }
11540 
11541 /// Checks whether the given value, which currently has the given
11542 /// source semantics, has the same value when coerced through the
11543 /// target semantics.
11544 ///
11545 /// The value might be a vector of floats (or a complex number).
11546 static bool IsSameFloatAfterCast(const APValue &value,
11547                                  const llvm::fltSemantics &Src,
11548                                  const llvm::fltSemantics &Tgt) {
11549   if (value.isFloat())
11550     return IsSameFloatAfterCast(value.getFloat(), Src, Tgt);
11551 
11552   if (value.isVector()) {
11553     for (unsigned i = 0, e = value.getVectorLength(); i != e; ++i)
11554       if (!IsSameFloatAfterCast(value.getVectorElt(i), Src, Tgt))
11555         return false;
11556     return true;
11557   }
11558 
11559   assert(value.isComplexFloat());
11560   return (IsSameFloatAfterCast(value.getComplexFloatReal(), Src, Tgt) &&
11561           IsSameFloatAfterCast(value.getComplexFloatImag(), Src, Tgt));
11562 }
11563 
11564 static void AnalyzeImplicitConversions(Sema &S, Expr *E, SourceLocation CC,
11565                                        bool IsListInit = false);
11566 
11567 static bool IsEnumConstOrFromMacro(Sema &S, Expr *E) {
11568   // Suppress cases where we are comparing against an enum constant.
11569   if (const DeclRefExpr *DR =
11570       dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts()))
11571     if (isa<EnumConstantDecl>(DR->getDecl()))
11572       return true;
11573 
11574   // Suppress cases where the value is expanded from a macro, unless that macro
11575   // is how a language represents a boolean literal. This is the case in both C
11576   // and Objective-C.
11577   SourceLocation BeginLoc = E->getBeginLoc();
11578   if (BeginLoc.isMacroID()) {
11579     StringRef MacroName = Lexer::getImmediateMacroName(
11580         BeginLoc, S.getSourceManager(), S.getLangOpts());
11581     return MacroName != "YES" && MacroName != "NO" &&
11582            MacroName != "true" && MacroName != "false";
11583   }
11584 
11585   return false;
11586 }
11587 
11588 static bool isKnownToHaveUnsignedValue(Expr *E) {
11589   return E->getType()->isIntegerType() &&
11590          (!E->getType()->isSignedIntegerType() ||
11591           !E->IgnoreParenImpCasts()->getType()->isSignedIntegerType());
11592 }
11593 
11594 namespace {
11595 /// The promoted range of values of a type. In general this has the
11596 /// following structure:
11597 ///
11598 ///     |-----------| . . . |-----------|
11599 ///     ^           ^       ^           ^
11600 ///    Min       HoleMin  HoleMax      Max
11601 ///
11602 /// ... where there is only a hole if a signed type is promoted to unsigned
11603 /// (in which case Min and Max are the smallest and largest representable
11604 /// values).
11605 struct PromotedRange {
11606   // Min, or HoleMax if there is a hole.
11607   llvm::APSInt PromotedMin;
11608   // Max, or HoleMin if there is a hole.
11609   llvm::APSInt PromotedMax;
11610 
11611   PromotedRange(IntRange R, unsigned BitWidth, bool Unsigned) {
11612     if (R.Width == 0)
11613       PromotedMin = PromotedMax = llvm::APSInt(BitWidth, Unsigned);
11614     else if (R.Width >= BitWidth && !Unsigned) {
11615       // Promotion made the type *narrower*. This happens when promoting
11616       // a < 32-bit unsigned / <= 32-bit signed bit-field to 'signed int'.
11617       // Treat all values of 'signed int' as being in range for now.
11618       PromotedMin = llvm::APSInt::getMinValue(BitWidth, Unsigned);
11619       PromotedMax = llvm::APSInt::getMaxValue(BitWidth, Unsigned);
11620     } else {
11621       PromotedMin = llvm::APSInt::getMinValue(R.Width, R.NonNegative)
11622                         .extOrTrunc(BitWidth);
11623       PromotedMin.setIsUnsigned(Unsigned);
11624 
11625       PromotedMax = llvm::APSInt::getMaxValue(R.Width, R.NonNegative)
11626                         .extOrTrunc(BitWidth);
11627       PromotedMax.setIsUnsigned(Unsigned);
11628     }
11629   }
11630 
11631   // Determine whether this range is contiguous (has no hole).
11632   bool isContiguous() const { return PromotedMin <= PromotedMax; }
11633 
11634   // Where a constant value is within the range.
11635   enum ComparisonResult {
11636     LT = 0x1,
11637     LE = 0x2,
11638     GT = 0x4,
11639     GE = 0x8,
11640     EQ = 0x10,
11641     NE = 0x20,
11642     InRangeFlag = 0x40,
11643 
11644     Less = LE | LT | NE,
11645     Min = LE | InRangeFlag,
11646     InRange = InRangeFlag,
11647     Max = GE | InRangeFlag,
11648     Greater = GE | GT | NE,
11649 
11650     OnlyValue = LE | GE | EQ | InRangeFlag,
11651     InHole = NE
11652   };
11653 
11654   ComparisonResult compare(const llvm::APSInt &Value) const {
11655     assert(Value.getBitWidth() == PromotedMin.getBitWidth() &&
11656            Value.isUnsigned() == PromotedMin.isUnsigned());
11657     if (!isContiguous()) {
11658       assert(Value.isUnsigned() && "discontiguous range for signed compare");
11659       if (Value.isMinValue()) return Min;
11660       if (Value.isMaxValue()) return Max;
11661       if (Value >= PromotedMin) return InRange;
11662       if (Value <= PromotedMax) return InRange;
11663       return InHole;
11664     }
11665 
11666     switch (llvm::APSInt::compareValues(Value, PromotedMin)) {
11667     case -1: return Less;
11668     case 0: return PromotedMin == PromotedMax ? OnlyValue : Min;
11669     case 1:
11670       switch (llvm::APSInt::compareValues(Value, PromotedMax)) {
11671       case -1: return InRange;
11672       case 0: return Max;
11673       case 1: return Greater;
11674       }
11675     }
11676 
11677     llvm_unreachable("impossible compare result");
11678   }
11679 
11680   static llvm::Optional<StringRef>
11681   constantValue(BinaryOperatorKind Op, ComparisonResult R, bool ConstantOnRHS) {
11682     if (Op == BO_Cmp) {
11683       ComparisonResult LTFlag = LT, GTFlag = GT;
11684       if (ConstantOnRHS) std::swap(LTFlag, GTFlag);
11685 
11686       if (R & EQ) return StringRef("'std::strong_ordering::equal'");
11687       if (R & LTFlag) return StringRef("'std::strong_ordering::less'");
11688       if (R & GTFlag) return StringRef("'std::strong_ordering::greater'");
11689       return llvm::None;
11690     }
11691 
11692     ComparisonResult TrueFlag, FalseFlag;
11693     if (Op == BO_EQ) {
11694       TrueFlag = EQ;
11695       FalseFlag = NE;
11696     } else if (Op == BO_NE) {
11697       TrueFlag = NE;
11698       FalseFlag = EQ;
11699     } else {
11700       if ((Op == BO_LT || Op == BO_GE) ^ ConstantOnRHS) {
11701         TrueFlag = LT;
11702         FalseFlag = GE;
11703       } else {
11704         TrueFlag = GT;
11705         FalseFlag = LE;
11706       }
11707       if (Op == BO_GE || Op == BO_LE)
11708         std::swap(TrueFlag, FalseFlag);
11709     }
11710     if (R & TrueFlag)
11711       return StringRef("true");
11712     if (R & FalseFlag)
11713       return StringRef("false");
11714     return llvm::None;
11715   }
11716 };
11717 }
11718 
11719 static bool HasEnumType(Expr *E) {
11720   // Strip off implicit integral promotions.
11721   while (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) {
11722     if (ICE->getCastKind() != CK_IntegralCast &&
11723         ICE->getCastKind() != CK_NoOp)
11724       break;
11725     E = ICE->getSubExpr();
11726   }
11727 
11728   return E->getType()->isEnumeralType();
11729 }
11730 
11731 static int classifyConstantValue(Expr *Constant) {
11732   // The values of this enumeration are used in the diagnostics
11733   // diag::warn_out_of_range_compare and diag::warn_tautological_bool_compare.
11734   enum ConstantValueKind {
11735     Miscellaneous = 0,
11736     LiteralTrue,
11737     LiteralFalse
11738   };
11739   if (auto *BL = dyn_cast<CXXBoolLiteralExpr>(Constant))
11740     return BL->getValue() ? ConstantValueKind::LiteralTrue
11741                           : ConstantValueKind::LiteralFalse;
11742   return ConstantValueKind::Miscellaneous;
11743 }
11744 
11745 static bool CheckTautologicalComparison(Sema &S, BinaryOperator *E,
11746                                         Expr *Constant, Expr *Other,
11747                                         const llvm::APSInt &Value,
11748                                         bool RhsConstant) {
11749   if (S.inTemplateInstantiation())
11750     return false;
11751 
11752   Expr *OriginalOther = Other;
11753 
11754   Constant = Constant->IgnoreParenImpCasts();
11755   Other = Other->IgnoreParenImpCasts();
11756 
11757   // Suppress warnings on tautological comparisons between values of the same
11758   // enumeration type. There are only two ways we could warn on this:
11759   //  - If the constant is outside the range of representable values of
11760   //    the enumeration. In such a case, we should warn about the cast
11761   //    to enumeration type, not about the comparison.
11762   //  - If the constant is the maximum / minimum in-range value. For an
11763   //    enumeratin type, such comparisons can be meaningful and useful.
11764   if (Constant->getType()->isEnumeralType() &&
11765       S.Context.hasSameUnqualifiedType(Constant->getType(), Other->getType()))
11766     return false;
11767 
11768   IntRange OtherValueRange = GetExprRange(
11769       S.Context, Other, S.isConstantEvaluated(), /*Approximate*/ false);
11770 
11771   QualType OtherT = Other->getType();
11772   if (const auto *AT = OtherT->getAs<AtomicType>())
11773     OtherT = AT->getValueType();
11774   IntRange OtherTypeRange = IntRange::forValueOfType(S.Context, OtherT);
11775 
11776   // Special case for ObjC BOOL on targets where its a typedef for a signed char
11777   // (Namely, macOS). FIXME: IntRange::forValueOfType should do this.
11778   bool IsObjCSignedCharBool = S.getLangOpts().ObjC &&
11779                               S.NSAPIObj->isObjCBOOLType(OtherT) &&
11780                               OtherT->isSpecificBuiltinType(BuiltinType::SChar);
11781 
11782   // Whether we're treating Other as being a bool because of the form of
11783   // expression despite it having another type (typically 'int' in C).
11784   bool OtherIsBooleanDespiteType =
11785       !OtherT->isBooleanType() && Other->isKnownToHaveBooleanValue();
11786   if (OtherIsBooleanDespiteType || IsObjCSignedCharBool)
11787     OtherTypeRange = OtherValueRange = IntRange::forBoolType();
11788 
11789   // Check if all values in the range of possible values of this expression
11790   // lead to the same comparison outcome.
11791   PromotedRange OtherPromotedValueRange(OtherValueRange, Value.getBitWidth(),
11792                                         Value.isUnsigned());
11793   auto Cmp = OtherPromotedValueRange.compare(Value);
11794   auto Result = PromotedRange::constantValue(E->getOpcode(), Cmp, RhsConstant);
11795   if (!Result)
11796     return false;
11797 
11798   // Also consider the range determined by the type alone. This allows us to
11799   // classify the warning under the proper diagnostic group.
11800   bool TautologicalTypeCompare = false;
11801   {
11802     PromotedRange OtherPromotedTypeRange(OtherTypeRange, Value.getBitWidth(),
11803                                          Value.isUnsigned());
11804     auto TypeCmp = OtherPromotedTypeRange.compare(Value);
11805     if (auto TypeResult = PromotedRange::constantValue(E->getOpcode(), TypeCmp,
11806                                                        RhsConstant)) {
11807       TautologicalTypeCompare = true;
11808       Cmp = TypeCmp;
11809       Result = TypeResult;
11810     }
11811   }
11812 
11813   // Don't warn if the non-constant operand actually always evaluates to the
11814   // same value.
11815   if (!TautologicalTypeCompare && OtherValueRange.Width == 0)
11816     return false;
11817 
11818   // Suppress the diagnostic for an in-range comparison if the constant comes
11819   // from a macro or enumerator. We don't want to diagnose
11820   //
11821   //   some_long_value <= INT_MAX
11822   //
11823   // when sizeof(int) == sizeof(long).
11824   bool InRange = Cmp & PromotedRange::InRangeFlag;
11825   if (InRange && IsEnumConstOrFromMacro(S, Constant))
11826     return false;
11827 
11828   // A comparison of an unsigned bit-field against 0 is really a type problem,
11829   // even though at the type level the bit-field might promote to 'signed int'.
11830   if (Other->refersToBitField() && InRange && Value == 0 &&
11831       Other->getType()->isUnsignedIntegerOrEnumerationType())
11832     TautologicalTypeCompare = true;
11833 
11834   // If this is a comparison to an enum constant, include that
11835   // constant in the diagnostic.
11836   const EnumConstantDecl *ED = nullptr;
11837   if (const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(Constant))
11838     ED = dyn_cast<EnumConstantDecl>(DR->getDecl());
11839 
11840   // Should be enough for uint128 (39 decimal digits)
11841   SmallString<64> PrettySourceValue;
11842   llvm::raw_svector_ostream OS(PrettySourceValue);
11843   if (ED) {
11844     OS << '\'' << *ED << "' (" << Value << ")";
11845   } else if (auto *BL = dyn_cast<ObjCBoolLiteralExpr>(
11846                Constant->IgnoreParenImpCasts())) {
11847     OS << (BL->getValue() ? "YES" : "NO");
11848   } else {
11849     OS << Value;
11850   }
11851 
11852   if (!TautologicalTypeCompare) {
11853     S.Diag(E->getOperatorLoc(), diag::warn_tautological_compare_value_range)
11854         << RhsConstant << OtherValueRange.Width << OtherValueRange.NonNegative
11855         << E->getOpcodeStr() << OS.str() << *Result
11856         << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange();
11857     return true;
11858   }
11859 
11860   if (IsObjCSignedCharBool) {
11861     S.DiagRuntimeBehavior(E->getOperatorLoc(), E,
11862                           S.PDiag(diag::warn_tautological_compare_objc_bool)
11863                               << OS.str() << *Result);
11864     return true;
11865   }
11866 
11867   // FIXME: We use a somewhat different formatting for the in-range cases and
11868   // cases involving boolean values for historical reasons. We should pick a
11869   // consistent way of presenting these diagnostics.
11870   if (!InRange || Other->isKnownToHaveBooleanValue()) {
11871 
11872     S.DiagRuntimeBehavior(
11873         E->getOperatorLoc(), E,
11874         S.PDiag(!InRange ? diag::warn_out_of_range_compare
11875                          : diag::warn_tautological_bool_compare)
11876             << OS.str() << classifyConstantValue(Constant) << OtherT
11877             << OtherIsBooleanDespiteType << *Result
11878             << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange());
11879   } else {
11880     bool IsCharTy = OtherT.withoutLocalFastQualifiers() == S.Context.CharTy;
11881     unsigned Diag =
11882         (isKnownToHaveUnsignedValue(OriginalOther) && Value == 0)
11883             ? (HasEnumType(OriginalOther)
11884                    ? diag::warn_unsigned_enum_always_true_comparison
11885                    : IsCharTy ? diag::warn_unsigned_char_always_true_comparison
11886                               : diag::warn_unsigned_always_true_comparison)
11887             : diag::warn_tautological_constant_compare;
11888 
11889     S.Diag(E->getOperatorLoc(), Diag)
11890         << RhsConstant << OtherT << E->getOpcodeStr() << OS.str() << *Result
11891         << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange();
11892   }
11893 
11894   return true;
11895 }
11896 
11897 /// Analyze the operands of the given comparison.  Implements the
11898 /// fallback case from AnalyzeComparison.
11899 static void AnalyzeImpConvsInComparison(Sema &S, BinaryOperator *E) {
11900   AnalyzeImplicitConversions(S, E->getLHS(), E->getOperatorLoc());
11901   AnalyzeImplicitConversions(S, E->getRHS(), E->getOperatorLoc());
11902 }
11903 
11904 /// Implements -Wsign-compare.
11905 ///
11906 /// \param E the binary operator to check for warnings
11907 static void AnalyzeComparison(Sema &S, BinaryOperator *E) {
11908   // The type the comparison is being performed in.
11909   QualType T = E->getLHS()->getType();
11910 
11911   // Only analyze comparison operators where both sides have been converted to
11912   // the same type.
11913   if (!S.Context.hasSameUnqualifiedType(T, E->getRHS()->getType()))
11914     return AnalyzeImpConvsInComparison(S, E);
11915 
11916   // Don't analyze value-dependent comparisons directly.
11917   if (E->isValueDependent())
11918     return AnalyzeImpConvsInComparison(S, E);
11919 
11920   Expr *LHS = E->getLHS();
11921   Expr *RHS = E->getRHS();
11922 
11923   if (T->isIntegralType(S.Context)) {
11924     Optional<llvm::APSInt> RHSValue = RHS->getIntegerConstantExpr(S.Context);
11925     Optional<llvm::APSInt> LHSValue = LHS->getIntegerConstantExpr(S.Context);
11926 
11927     // We don't care about expressions whose result is a constant.
11928     if (RHSValue && LHSValue)
11929       return AnalyzeImpConvsInComparison(S, E);
11930 
11931     // We only care about expressions where just one side is literal
11932     if ((bool)RHSValue ^ (bool)LHSValue) {
11933       // Is the constant on the RHS or LHS?
11934       const bool RhsConstant = (bool)RHSValue;
11935       Expr *Const = RhsConstant ? RHS : LHS;
11936       Expr *Other = RhsConstant ? LHS : RHS;
11937       const llvm::APSInt &Value = RhsConstant ? *RHSValue : *LHSValue;
11938 
11939       // Check whether an integer constant comparison results in a value
11940       // of 'true' or 'false'.
11941       if (CheckTautologicalComparison(S, E, Const, Other, Value, RhsConstant))
11942         return AnalyzeImpConvsInComparison(S, E);
11943     }
11944   }
11945 
11946   if (!T->hasUnsignedIntegerRepresentation()) {
11947     // We don't do anything special if this isn't an unsigned integral
11948     // comparison:  we're only interested in integral comparisons, and
11949     // signed comparisons only happen in cases we don't care to warn about.
11950     return AnalyzeImpConvsInComparison(S, E);
11951   }
11952 
11953   LHS = LHS->IgnoreParenImpCasts();
11954   RHS = RHS->IgnoreParenImpCasts();
11955 
11956   if (!S.getLangOpts().CPlusPlus) {
11957     // Avoid warning about comparison of integers with different signs when
11958     // RHS/LHS has a `typeof(E)` type whose sign is different from the sign of
11959     // the type of `E`.
11960     if (const auto *TET = dyn_cast<TypeOfExprType>(LHS->getType()))
11961       LHS = TET->getUnderlyingExpr()->IgnoreParenImpCasts();
11962     if (const auto *TET = dyn_cast<TypeOfExprType>(RHS->getType()))
11963       RHS = TET->getUnderlyingExpr()->IgnoreParenImpCasts();
11964   }
11965 
11966   // Check to see if one of the (unmodified) operands is of different
11967   // signedness.
11968   Expr *signedOperand, *unsignedOperand;
11969   if (LHS->getType()->hasSignedIntegerRepresentation()) {
11970     assert(!RHS->getType()->hasSignedIntegerRepresentation() &&
11971            "unsigned comparison between two signed integer expressions?");
11972     signedOperand = LHS;
11973     unsignedOperand = RHS;
11974   } else if (RHS->getType()->hasSignedIntegerRepresentation()) {
11975     signedOperand = RHS;
11976     unsignedOperand = LHS;
11977   } else {
11978     return AnalyzeImpConvsInComparison(S, E);
11979   }
11980 
11981   // Otherwise, calculate the effective range of the signed operand.
11982   IntRange signedRange = GetExprRange(
11983       S.Context, signedOperand, S.isConstantEvaluated(), /*Approximate*/ true);
11984 
11985   // Go ahead and analyze implicit conversions in the operands.  Note
11986   // that we skip the implicit conversions on both sides.
11987   AnalyzeImplicitConversions(S, LHS, E->getOperatorLoc());
11988   AnalyzeImplicitConversions(S, RHS, E->getOperatorLoc());
11989 
11990   // If the signed range is non-negative, -Wsign-compare won't fire.
11991   if (signedRange.NonNegative)
11992     return;
11993 
11994   // For (in)equality comparisons, if the unsigned operand is a
11995   // constant which cannot collide with a overflowed signed operand,
11996   // then reinterpreting the signed operand as unsigned will not
11997   // change the result of the comparison.
11998   if (E->isEqualityOp()) {
11999     unsigned comparisonWidth = S.Context.getIntWidth(T);
12000     IntRange unsignedRange =
12001         GetExprRange(S.Context, unsignedOperand, S.isConstantEvaluated(),
12002                      /*Approximate*/ true);
12003 
12004     // We should never be unable to prove that the unsigned operand is
12005     // non-negative.
12006     assert(unsignedRange.NonNegative && "unsigned range includes negative?");
12007 
12008     if (unsignedRange.Width < comparisonWidth)
12009       return;
12010   }
12011 
12012   S.DiagRuntimeBehavior(E->getOperatorLoc(), E,
12013                         S.PDiag(diag::warn_mixed_sign_comparison)
12014                             << LHS->getType() << RHS->getType()
12015                             << LHS->getSourceRange() << RHS->getSourceRange());
12016 }
12017 
12018 /// Analyzes an attempt to assign the given value to a bitfield.
12019 ///
12020 /// Returns true if there was something fishy about the attempt.
12021 static bool AnalyzeBitFieldAssignment(Sema &S, FieldDecl *Bitfield, Expr *Init,
12022                                       SourceLocation InitLoc) {
12023   assert(Bitfield->isBitField());
12024   if (Bitfield->isInvalidDecl())
12025     return false;
12026 
12027   // White-list bool bitfields.
12028   QualType BitfieldType = Bitfield->getType();
12029   if (BitfieldType->isBooleanType())
12030      return false;
12031 
12032   if (BitfieldType->isEnumeralType()) {
12033     EnumDecl *BitfieldEnumDecl = BitfieldType->castAs<EnumType>()->getDecl();
12034     // If the underlying enum type was not explicitly specified as an unsigned
12035     // type and the enum contain only positive values, MSVC++ will cause an
12036     // inconsistency by storing this as a signed type.
12037     if (S.getLangOpts().CPlusPlus11 &&
12038         !BitfieldEnumDecl->getIntegerTypeSourceInfo() &&
12039         BitfieldEnumDecl->getNumPositiveBits() > 0 &&
12040         BitfieldEnumDecl->getNumNegativeBits() == 0) {
12041       S.Diag(InitLoc, diag::warn_no_underlying_type_specified_for_enum_bitfield)
12042           << BitfieldEnumDecl;
12043     }
12044   }
12045 
12046   if (Bitfield->getType()->isBooleanType())
12047     return false;
12048 
12049   // Ignore value- or type-dependent expressions.
12050   if (Bitfield->getBitWidth()->isValueDependent() ||
12051       Bitfield->getBitWidth()->isTypeDependent() ||
12052       Init->isValueDependent() ||
12053       Init->isTypeDependent())
12054     return false;
12055 
12056   Expr *OriginalInit = Init->IgnoreParenImpCasts();
12057   unsigned FieldWidth = Bitfield->getBitWidthValue(S.Context);
12058 
12059   Expr::EvalResult Result;
12060   if (!OriginalInit->EvaluateAsInt(Result, S.Context,
12061                                    Expr::SE_AllowSideEffects)) {
12062     // The RHS is not constant.  If the RHS has an enum type, make sure the
12063     // bitfield is wide enough to hold all the values of the enum without
12064     // truncation.
12065     if (const auto *EnumTy = OriginalInit->getType()->getAs<EnumType>()) {
12066       EnumDecl *ED = EnumTy->getDecl();
12067       bool SignedBitfield = BitfieldType->isSignedIntegerType();
12068 
12069       // Enum types are implicitly signed on Windows, so check if there are any
12070       // negative enumerators to see if the enum was intended to be signed or
12071       // not.
12072       bool SignedEnum = ED->getNumNegativeBits() > 0;
12073 
12074       // Check for surprising sign changes when assigning enum values to a
12075       // bitfield of different signedness.  If the bitfield is signed and we
12076       // have exactly the right number of bits to store this unsigned enum,
12077       // suggest changing the enum to an unsigned type. This typically happens
12078       // on Windows where unfixed enums always use an underlying type of 'int'.
12079       unsigned DiagID = 0;
12080       if (SignedEnum && !SignedBitfield) {
12081         DiagID = diag::warn_unsigned_bitfield_assigned_signed_enum;
12082       } else if (SignedBitfield && !SignedEnum &&
12083                  ED->getNumPositiveBits() == FieldWidth) {
12084         DiagID = diag::warn_signed_bitfield_enum_conversion;
12085       }
12086 
12087       if (DiagID) {
12088         S.Diag(InitLoc, DiagID) << Bitfield << ED;
12089         TypeSourceInfo *TSI = Bitfield->getTypeSourceInfo();
12090         SourceRange TypeRange =
12091             TSI ? TSI->getTypeLoc().getSourceRange() : SourceRange();
12092         S.Diag(Bitfield->getTypeSpecStartLoc(), diag::note_change_bitfield_sign)
12093             << SignedEnum << TypeRange;
12094       }
12095 
12096       // Compute the required bitwidth. If the enum has negative values, we need
12097       // one more bit than the normal number of positive bits to represent the
12098       // sign bit.
12099       unsigned BitsNeeded = SignedEnum ? std::max(ED->getNumPositiveBits() + 1,
12100                                                   ED->getNumNegativeBits())
12101                                        : ED->getNumPositiveBits();
12102 
12103       // Check the bitwidth.
12104       if (BitsNeeded > FieldWidth) {
12105         Expr *WidthExpr = Bitfield->getBitWidth();
12106         S.Diag(InitLoc, diag::warn_bitfield_too_small_for_enum)
12107             << Bitfield << ED;
12108         S.Diag(WidthExpr->getExprLoc(), diag::note_widen_bitfield)
12109             << BitsNeeded << ED << WidthExpr->getSourceRange();
12110       }
12111     }
12112 
12113     return false;
12114   }
12115 
12116   llvm::APSInt Value = Result.Val.getInt();
12117 
12118   unsigned OriginalWidth = Value.getBitWidth();
12119 
12120   if (!Value.isSigned() || Value.isNegative())
12121     if (UnaryOperator *UO = dyn_cast<UnaryOperator>(OriginalInit))
12122       if (UO->getOpcode() == UO_Minus || UO->getOpcode() == UO_Not)
12123         OriginalWidth = Value.getMinSignedBits();
12124 
12125   if (OriginalWidth <= FieldWidth)
12126     return false;
12127 
12128   // Compute the value which the bitfield will contain.
12129   llvm::APSInt TruncatedValue = Value.trunc(FieldWidth);
12130   TruncatedValue.setIsSigned(BitfieldType->isSignedIntegerType());
12131 
12132   // Check whether the stored value is equal to the original value.
12133   TruncatedValue = TruncatedValue.extend(OriginalWidth);
12134   if (llvm::APSInt::isSameValue(Value, TruncatedValue))
12135     return false;
12136 
12137   // Special-case bitfields of width 1: booleans are naturally 0/1, and
12138   // therefore don't strictly fit into a signed bitfield of width 1.
12139   if (FieldWidth == 1 && Value == 1)
12140     return false;
12141 
12142   std::string PrettyValue = toString(Value, 10);
12143   std::string PrettyTrunc = toString(TruncatedValue, 10);
12144 
12145   S.Diag(InitLoc, diag::warn_impcast_bitfield_precision_constant)
12146     << PrettyValue << PrettyTrunc << OriginalInit->getType()
12147     << Init->getSourceRange();
12148 
12149   return true;
12150 }
12151 
12152 /// Analyze the given simple or compound assignment for warning-worthy
12153 /// operations.
12154 static void AnalyzeAssignment(Sema &S, BinaryOperator *E) {
12155   // Just recurse on the LHS.
12156   AnalyzeImplicitConversions(S, E->getLHS(), E->getOperatorLoc());
12157 
12158   // We want to recurse on the RHS as normal unless we're assigning to
12159   // a bitfield.
12160   if (FieldDecl *Bitfield = E->getLHS()->getSourceBitField()) {
12161     if (AnalyzeBitFieldAssignment(S, Bitfield, E->getRHS(),
12162                                   E->getOperatorLoc())) {
12163       // Recurse, ignoring any implicit conversions on the RHS.
12164       return AnalyzeImplicitConversions(S, E->getRHS()->IgnoreParenImpCasts(),
12165                                         E->getOperatorLoc());
12166     }
12167   }
12168 
12169   AnalyzeImplicitConversions(S, E->getRHS(), E->getOperatorLoc());
12170 
12171   // Diagnose implicitly sequentially-consistent atomic assignment.
12172   if (E->getLHS()->getType()->isAtomicType())
12173     S.Diag(E->getRHS()->getBeginLoc(), diag::warn_atomic_implicit_seq_cst);
12174 }
12175 
12176 /// Diagnose an implicit cast;  purely a helper for CheckImplicitConversion.
12177 static void DiagnoseImpCast(Sema &S, Expr *E, QualType SourceType, QualType T,
12178                             SourceLocation CContext, unsigned diag,
12179                             bool pruneControlFlow = false) {
12180   if (pruneControlFlow) {
12181     S.DiagRuntimeBehavior(E->getExprLoc(), E,
12182                           S.PDiag(diag)
12183                               << SourceType << T << E->getSourceRange()
12184                               << SourceRange(CContext));
12185     return;
12186   }
12187   S.Diag(E->getExprLoc(), diag)
12188     << SourceType << T << E->getSourceRange() << SourceRange(CContext);
12189 }
12190 
12191 /// Diagnose an implicit cast;  purely a helper for CheckImplicitConversion.
12192 static void DiagnoseImpCast(Sema &S, Expr *E, QualType T,
12193                             SourceLocation CContext,
12194                             unsigned diag, bool pruneControlFlow = false) {
12195   DiagnoseImpCast(S, E, E->getType(), T, CContext, diag, pruneControlFlow);
12196 }
12197 
12198 static bool isObjCSignedCharBool(Sema &S, QualType Ty) {
12199   return Ty->isSpecificBuiltinType(BuiltinType::SChar) &&
12200       S.getLangOpts().ObjC && S.NSAPIObj->isObjCBOOLType(Ty);
12201 }
12202 
12203 static void adornObjCBoolConversionDiagWithTernaryFixit(
12204     Sema &S, Expr *SourceExpr, const Sema::SemaDiagnosticBuilder &Builder) {
12205   Expr *Ignored = SourceExpr->IgnoreImplicit();
12206   if (const auto *OVE = dyn_cast<OpaqueValueExpr>(Ignored))
12207     Ignored = OVE->getSourceExpr();
12208   bool NeedsParens = isa<AbstractConditionalOperator>(Ignored) ||
12209                      isa<BinaryOperator>(Ignored) ||
12210                      isa<CXXOperatorCallExpr>(Ignored);
12211   SourceLocation EndLoc = S.getLocForEndOfToken(SourceExpr->getEndLoc());
12212   if (NeedsParens)
12213     Builder << FixItHint::CreateInsertion(SourceExpr->getBeginLoc(), "(")
12214             << FixItHint::CreateInsertion(EndLoc, ")");
12215   Builder << FixItHint::CreateInsertion(EndLoc, " ? YES : NO");
12216 }
12217 
12218 /// Diagnose an implicit cast from a floating point value to an integer value.
12219 static void DiagnoseFloatingImpCast(Sema &S, Expr *E, QualType T,
12220                                     SourceLocation CContext) {
12221   const bool IsBool = T->isSpecificBuiltinType(BuiltinType::Bool);
12222   const bool PruneWarnings = S.inTemplateInstantiation();
12223 
12224   Expr *InnerE = E->IgnoreParenImpCasts();
12225   // We also want to warn on, e.g., "int i = -1.234"
12226   if (UnaryOperator *UOp = dyn_cast<UnaryOperator>(InnerE))
12227     if (UOp->getOpcode() == UO_Minus || UOp->getOpcode() == UO_Plus)
12228       InnerE = UOp->getSubExpr()->IgnoreParenImpCasts();
12229 
12230   const bool IsLiteral =
12231       isa<FloatingLiteral>(E) || isa<FloatingLiteral>(InnerE);
12232 
12233   llvm::APFloat Value(0.0);
12234   bool IsConstant =
12235     E->EvaluateAsFloat(Value, S.Context, Expr::SE_AllowSideEffects);
12236   if (!IsConstant) {
12237     if (isObjCSignedCharBool(S, T)) {
12238       return adornObjCBoolConversionDiagWithTernaryFixit(
12239           S, E,
12240           S.Diag(CContext, diag::warn_impcast_float_to_objc_signed_char_bool)
12241               << E->getType());
12242     }
12243 
12244     return DiagnoseImpCast(S, E, T, CContext,
12245                            diag::warn_impcast_float_integer, PruneWarnings);
12246   }
12247 
12248   bool isExact = false;
12249 
12250   llvm::APSInt IntegerValue(S.Context.getIntWidth(T),
12251                             T->hasUnsignedIntegerRepresentation());
12252   llvm::APFloat::opStatus Result = Value.convertToInteger(
12253       IntegerValue, llvm::APFloat::rmTowardZero, &isExact);
12254 
12255   // FIXME: Force the precision of the source value down so we don't print
12256   // digits which are usually useless (we don't really care here if we
12257   // truncate a digit by accident in edge cases).  Ideally, APFloat::toString
12258   // would automatically print the shortest representation, but it's a bit
12259   // tricky to implement.
12260   SmallString<16> PrettySourceValue;
12261   unsigned precision = llvm::APFloat::semanticsPrecision(Value.getSemantics());
12262   precision = (precision * 59 + 195) / 196;
12263   Value.toString(PrettySourceValue, precision);
12264 
12265   if (isObjCSignedCharBool(S, T) && IntegerValue != 0 && IntegerValue != 1) {
12266     return adornObjCBoolConversionDiagWithTernaryFixit(
12267         S, E,
12268         S.Diag(CContext, diag::warn_impcast_constant_value_to_objc_bool)
12269             << PrettySourceValue);
12270   }
12271 
12272   if (Result == llvm::APFloat::opOK && isExact) {
12273     if (IsLiteral) return;
12274     return DiagnoseImpCast(S, E, T, CContext, diag::warn_impcast_float_integer,
12275                            PruneWarnings);
12276   }
12277 
12278   // Conversion of a floating-point value to a non-bool integer where the
12279   // integral part cannot be represented by the integer type is undefined.
12280   if (!IsBool && Result == llvm::APFloat::opInvalidOp)
12281     return DiagnoseImpCast(
12282         S, E, T, CContext,
12283         IsLiteral ? diag::warn_impcast_literal_float_to_integer_out_of_range
12284                   : diag::warn_impcast_float_to_integer_out_of_range,
12285         PruneWarnings);
12286 
12287   unsigned DiagID = 0;
12288   if (IsLiteral) {
12289     // Warn on floating point literal to integer.
12290     DiagID = diag::warn_impcast_literal_float_to_integer;
12291   } else if (IntegerValue == 0) {
12292     if (Value.isZero()) {  // Skip -0.0 to 0 conversion.
12293       return DiagnoseImpCast(S, E, T, CContext,
12294                              diag::warn_impcast_float_integer, PruneWarnings);
12295     }
12296     // Warn on non-zero to zero conversion.
12297     DiagID = diag::warn_impcast_float_to_integer_zero;
12298   } else {
12299     if (IntegerValue.isUnsigned()) {
12300       if (!IntegerValue.isMaxValue()) {
12301         return DiagnoseImpCast(S, E, T, CContext,
12302                                diag::warn_impcast_float_integer, PruneWarnings);
12303       }
12304     } else {  // IntegerValue.isSigned()
12305       if (!IntegerValue.isMaxSignedValue() &&
12306           !IntegerValue.isMinSignedValue()) {
12307         return DiagnoseImpCast(S, E, T, CContext,
12308                                diag::warn_impcast_float_integer, PruneWarnings);
12309       }
12310     }
12311     // Warn on evaluatable floating point expression to integer conversion.
12312     DiagID = diag::warn_impcast_float_to_integer;
12313   }
12314 
12315   SmallString<16> PrettyTargetValue;
12316   if (IsBool)
12317     PrettyTargetValue = Value.isZero() ? "false" : "true";
12318   else
12319     IntegerValue.toString(PrettyTargetValue);
12320 
12321   if (PruneWarnings) {
12322     S.DiagRuntimeBehavior(E->getExprLoc(), E,
12323                           S.PDiag(DiagID)
12324                               << E->getType() << T.getUnqualifiedType()
12325                               << PrettySourceValue << PrettyTargetValue
12326                               << E->getSourceRange() << SourceRange(CContext));
12327   } else {
12328     S.Diag(E->getExprLoc(), DiagID)
12329         << E->getType() << T.getUnqualifiedType() << PrettySourceValue
12330         << PrettyTargetValue << E->getSourceRange() << SourceRange(CContext);
12331   }
12332 }
12333 
12334 /// Analyze the given compound assignment for the possible losing of
12335 /// floating-point precision.
12336 static void AnalyzeCompoundAssignment(Sema &S, BinaryOperator *E) {
12337   assert(isa<CompoundAssignOperator>(E) &&
12338          "Must be compound assignment operation");
12339   // Recurse on the LHS and RHS in here
12340   AnalyzeImplicitConversions(S, E->getLHS(), E->getOperatorLoc());
12341   AnalyzeImplicitConversions(S, E->getRHS(), E->getOperatorLoc());
12342 
12343   if (E->getLHS()->getType()->isAtomicType())
12344     S.Diag(E->getOperatorLoc(), diag::warn_atomic_implicit_seq_cst);
12345 
12346   // Now check the outermost expression
12347   const auto *ResultBT = E->getLHS()->getType()->getAs<BuiltinType>();
12348   const auto *RBT = cast<CompoundAssignOperator>(E)
12349                         ->getComputationResultType()
12350                         ->getAs<BuiltinType>();
12351 
12352   // The below checks assume source is floating point.
12353   if (!ResultBT || !RBT || !RBT->isFloatingPoint()) return;
12354 
12355   // If source is floating point but target is an integer.
12356   if (ResultBT->isInteger())
12357     return DiagnoseImpCast(S, E, E->getRHS()->getType(), E->getLHS()->getType(),
12358                            E->getExprLoc(), diag::warn_impcast_float_integer);
12359 
12360   if (!ResultBT->isFloatingPoint())
12361     return;
12362 
12363   // If both source and target are floating points, warn about losing precision.
12364   int Order = S.getASTContext().getFloatingTypeSemanticOrder(
12365       QualType(ResultBT, 0), QualType(RBT, 0));
12366   if (Order < 0 && !S.SourceMgr.isInSystemMacro(E->getOperatorLoc()))
12367     // warn about dropping FP rank.
12368     DiagnoseImpCast(S, E->getRHS(), E->getLHS()->getType(), E->getOperatorLoc(),
12369                     diag::warn_impcast_float_result_precision);
12370 }
12371 
12372 static std::string PrettyPrintInRange(const llvm::APSInt &Value,
12373                                       IntRange Range) {
12374   if (!Range.Width) return "0";
12375 
12376   llvm::APSInt ValueInRange = Value;
12377   ValueInRange.setIsSigned(!Range.NonNegative);
12378   ValueInRange = ValueInRange.trunc(Range.Width);
12379   return toString(ValueInRange, 10);
12380 }
12381 
12382 static bool IsImplicitBoolFloatConversion(Sema &S, Expr *Ex, bool ToBool) {
12383   if (!isa<ImplicitCastExpr>(Ex))
12384     return false;
12385 
12386   Expr *InnerE = Ex->IgnoreParenImpCasts();
12387   const Type *Target = S.Context.getCanonicalType(Ex->getType()).getTypePtr();
12388   const Type *Source =
12389     S.Context.getCanonicalType(InnerE->getType()).getTypePtr();
12390   if (Target->isDependentType())
12391     return false;
12392 
12393   const BuiltinType *FloatCandidateBT =
12394     dyn_cast<BuiltinType>(ToBool ? Source : Target);
12395   const Type *BoolCandidateType = ToBool ? Target : Source;
12396 
12397   return (BoolCandidateType->isSpecificBuiltinType(BuiltinType::Bool) &&
12398           FloatCandidateBT && (FloatCandidateBT->isFloatingPoint()));
12399 }
12400 
12401 static void CheckImplicitArgumentConversions(Sema &S, CallExpr *TheCall,
12402                                              SourceLocation CC) {
12403   unsigned NumArgs = TheCall->getNumArgs();
12404   for (unsigned i = 0; i < NumArgs; ++i) {
12405     Expr *CurrA = TheCall->getArg(i);
12406     if (!IsImplicitBoolFloatConversion(S, CurrA, true))
12407       continue;
12408 
12409     bool IsSwapped = ((i > 0) &&
12410         IsImplicitBoolFloatConversion(S, TheCall->getArg(i - 1), false));
12411     IsSwapped |= ((i < (NumArgs - 1)) &&
12412         IsImplicitBoolFloatConversion(S, TheCall->getArg(i + 1), false));
12413     if (IsSwapped) {
12414       // Warn on this floating-point to bool conversion.
12415       DiagnoseImpCast(S, CurrA->IgnoreParenImpCasts(),
12416                       CurrA->getType(), CC,
12417                       diag::warn_impcast_floating_point_to_bool);
12418     }
12419   }
12420 }
12421 
12422 static void DiagnoseNullConversion(Sema &S, Expr *E, QualType T,
12423                                    SourceLocation CC) {
12424   if (S.Diags.isIgnored(diag::warn_impcast_null_pointer_to_integer,
12425                         E->getExprLoc()))
12426     return;
12427 
12428   // Don't warn on functions which have return type nullptr_t.
12429   if (isa<CallExpr>(E))
12430     return;
12431 
12432   // Check for NULL (GNUNull) or nullptr (CXX11_nullptr).
12433   const Expr::NullPointerConstantKind NullKind =
12434       E->isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull);
12435   if (NullKind != Expr::NPCK_GNUNull && NullKind != Expr::NPCK_CXX11_nullptr)
12436     return;
12437 
12438   // Return if target type is a safe conversion.
12439   if (T->isAnyPointerType() || T->isBlockPointerType() ||
12440       T->isMemberPointerType() || !T->isScalarType() || T->isNullPtrType())
12441     return;
12442 
12443   SourceLocation Loc = E->getSourceRange().getBegin();
12444 
12445   // Venture through the macro stacks to get to the source of macro arguments.
12446   // The new location is a better location than the complete location that was
12447   // passed in.
12448   Loc = S.SourceMgr.getTopMacroCallerLoc(Loc);
12449   CC = S.SourceMgr.getTopMacroCallerLoc(CC);
12450 
12451   // __null is usually wrapped in a macro.  Go up a macro if that is the case.
12452   if (NullKind == Expr::NPCK_GNUNull && Loc.isMacroID()) {
12453     StringRef MacroName = Lexer::getImmediateMacroNameForDiagnostics(
12454         Loc, S.SourceMgr, S.getLangOpts());
12455     if (MacroName == "NULL")
12456       Loc = S.SourceMgr.getImmediateExpansionRange(Loc).getBegin();
12457   }
12458 
12459   // Only warn if the null and context location are in the same macro expansion.
12460   if (S.SourceMgr.getFileID(Loc) != S.SourceMgr.getFileID(CC))
12461     return;
12462 
12463   S.Diag(Loc, diag::warn_impcast_null_pointer_to_integer)
12464       << (NullKind == Expr::NPCK_CXX11_nullptr) << T << SourceRange(CC)
12465       << FixItHint::CreateReplacement(Loc,
12466                                       S.getFixItZeroLiteralForType(T, Loc));
12467 }
12468 
12469 static void checkObjCArrayLiteral(Sema &S, QualType TargetType,
12470                                   ObjCArrayLiteral *ArrayLiteral);
12471 
12472 static void
12473 checkObjCDictionaryLiteral(Sema &S, QualType TargetType,
12474                            ObjCDictionaryLiteral *DictionaryLiteral);
12475 
12476 /// Check a single element within a collection literal against the
12477 /// target element type.
12478 static void checkObjCCollectionLiteralElement(Sema &S,
12479                                               QualType TargetElementType,
12480                                               Expr *Element,
12481                                               unsigned ElementKind) {
12482   // Skip a bitcast to 'id' or qualified 'id'.
12483   if (auto ICE = dyn_cast<ImplicitCastExpr>(Element)) {
12484     if (ICE->getCastKind() == CK_BitCast &&
12485         ICE->getSubExpr()->getType()->getAs<ObjCObjectPointerType>())
12486       Element = ICE->getSubExpr();
12487   }
12488 
12489   QualType ElementType = Element->getType();
12490   ExprResult ElementResult(Element);
12491   if (ElementType->getAs<ObjCObjectPointerType>() &&
12492       S.CheckSingleAssignmentConstraints(TargetElementType,
12493                                          ElementResult,
12494                                          false, false)
12495         != Sema::Compatible) {
12496     S.Diag(Element->getBeginLoc(), diag::warn_objc_collection_literal_element)
12497         << ElementType << ElementKind << TargetElementType
12498         << Element->getSourceRange();
12499   }
12500 
12501   if (auto ArrayLiteral = dyn_cast<ObjCArrayLiteral>(Element))
12502     checkObjCArrayLiteral(S, TargetElementType, ArrayLiteral);
12503   else if (auto DictionaryLiteral = dyn_cast<ObjCDictionaryLiteral>(Element))
12504     checkObjCDictionaryLiteral(S, TargetElementType, DictionaryLiteral);
12505 }
12506 
12507 /// Check an Objective-C array literal being converted to the given
12508 /// target type.
12509 static void checkObjCArrayLiteral(Sema &S, QualType TargetType,
12510                                   ObjCArrayLiteral *ArrayLiteral) {
12511   if (!S.NSArrayDecl)
12512     return;
12513 
12514   const auto *TargetObjCPtr = TargetType->getAs<ObjCObjectPointerType>();
12515   if (!TargetObjCPtr)
12516     return;
12517 
12518   if (TargetObjCPtr->isUnspecialized() ||
12519       TargetObjCPtr->getInterfaceDecl()->getCanonicalDecl()
12520         != S.NSArrayDecl->getCanonicalDecl())
12521     return;
12522 
12523   auto TypeArgs = TargetObjCPtr->getTypeArgs();
12524   if (TypeArgs.size() != 1)
12525     return;
12526 
12527   QualType TargetElementType = TypeArgs[0];
12528   for (unsigned I = 0, N = ArrayLiteral->getNumElements(); I != N; ++I) {
12529     checkObjCCollectionLiteralElement(S, TargetElementType,
12530                                       ArrayLiteral->getElement(I),
12531                                       0);
12532   }
12533 }
12534 
12535 /// Check an Objective-C dictionary literal being converted to the given
12536 /// target type.
12537 static void
12538 checkObjCDictionaryLiteral(Sema &S, QualType TargetType,
12539                            ObjCDictionaryLiteral *DictionaryLiteral) {
12540   if (!S.NSDictionaryDecl)
12541     return;
12542 
12543   const auto *TargetObjCPtr = TargetType->getAs<ObjCObjectPointerType>();
12544   if (!TargetObjCPtr)
12545     return;
12546 
12547   if (TargetObjCPtr->isUnspecialized() ||
12548       TargetObjCPtr->getInterfaceDecl()->getCanonicalDecl()
12549         != S.NSDictionaryDecl->getCanonicalDecl())
12550     return;
12551 
12552   auto TypeArgs = TargetObjCPtr->getTypeArgs();
12553   if (TypeArgs.size() != 2)
12554     return;
12555 
12556   QualType TargetKeyType = TypeArgs[0];
12557   QualType TargetObjectType = TypeArgs[1];
12558   for (unsigned I = 0, N = DictionaryLiteral->getNumElements(); I != N; ++I) {
12559     auto Element = DictionaryLiteral->getKeyValueElement(I);
12560     checkObjCCollectionLiteralElement(S, TargetKeyType, Element.Key, 1);
12561     checkObjCCollectionLiteralElement(S, TargetObjectType, Element.Value, 2);
12562   }
12563 }
12564 
12565 // Helper function to filter out cases for constant width constant conversion.
12566 // Don't warn on char array initialization or for non-decimal values.
12567 static bool isSameWidthConstantConversion(Sema &S, Expr *E, QualType T,
12568                                           SourceLocation CC) {
12569   // If initializing from a constant, and the constant starts with '0',
12570   // then it is a binary, octal, or hexadecimal.  Allow these constants
12571   // to fill all the bits, even if there is a sign change.
12572   if (auto *IntLit = dyn_cast<IntegerLiteral>(E->IgnoreParenImpCasts())) {
12573     const char FirstLiteralCharacter =
12574         S.getSourceManager().getCharacterData(IntLit->getBeginLoc())[0];
12575     if (FirstLiteralCharacter == '0')
12576       return false;
12577   }
12578 
12579   // If the CC location points to a '{', and the type is char, then assume
12580   // assume it is an array initialization.
12581   if (CC.isValid() && T->isCharType()) {
12582     const char FirstContextCharacter =
12583         S.getSourceManager().getCharacterData(CC)[0];
12584     if (FirstContextCharacter == '{')
12585       return false;
12586   }
12587 
12588   return true;
12589 }
12590 
12591 static const IntegerLiteral *getIntegerLiteral(Expr *E) {
12592   const auto *IL = dyn_cast<IntegerLiteral>(E);
12593   if (!IL) {
12594     if (auto *UO = dyn_cast<UnaryOperator>(E)) {
12595       if (UO->getOpcode() == UO_Minus)
12596         return dyn_cast<IntegerLiteral>(UO->getSubExpr());
12597     }
12598   }
12599 
12600   return IL;
12601 }
12602 
12603 static void DiagnoseIntInBoolContext(Sema &S, Expr *E) {
12604   E = E->IgnoreParenImpCasts();
12605   SourceLocation ExprLoc = E->getExprLoc();
12606 
12607   if (const auto *BO = dyn_cast<BinaryOperator>(E)) {
12608     BinaryOperator::Opcode Opc = BO->getOpcode();
12609     Expr::EvalResult Result;
12610     // Do not diagnose unsigned shifts.
12611     if (Opc == BO_Shl) {
12612       const auto *LHS = getIntegerLiteral(BO->getLHS());
12613       const auto *RHS = getIntegerLiteral(BO->getRHS());
12614       if (LHS && LHS->getValue() == 0)
12615         S.Diag(ExprLoc, diag::warn_left_shift_always) << 0;
12616       else if (!E->isValueDependent() && LHS && RHS &&
12617                RHS->getValue().isNonNegative() &&
12618                E->EvaluateAsInt(Result, S.Context, Expr::SE_AllowSideEffects))
12619         S.Diag(ExprLoc, diag::warn_left_shift_always)
12620             << (Result.Val.getInt() != 0);
12621       else if (E->getType()->isSignedIntegerType())
12622         S.Diag(ExprLoc, diag::warn_left_shift_in_bool_context) << E;
12623     }
12624   }
12625 
12626   if (const auto *CO = dyn_cast<ConditionalOperator>(E)) {
12627     const auto *LHS = getIntegerLiteral(CO->getTrueExpr());
12628     const auto *RHS = getIntegerLiteral(CO->getFalseExpr());
12629     if (!LHS || !RHS)
12630       return;
12631     if ((LHS->getValue() == 0 || LHS->getValue() == 1) &&
12632         (RHS->getValue() == 0 || RHS->getValue() == 1))
12633       // Do not diagnose common idioms.
12634       return;
12635     if (LHS->getValue() != 0 && RHS->getValue() != 0)
12636       S.Diag(ExprLoc, diag::warn_integer_constants_in_conditional_always_true);
12637   }
12638 }
12639 
12640 static void CheckImplicitConversion(Sema &S, Expr *E, QualType T,
12641                                     SourceLocation CC,
12642                                     bool *ICContext = nullptr,
12643                                     bool IsListInit = false) {
12644   if (E->isTypeDependent() || E->isValueDependent()) return;
12645 
12646   const Type *Source = S.Context.getCanonicalType(E->getType()).getTypePtr();
12647   const Type *Target = S.Context.getCanonicalType(T).getTypePtr();
12648   if (Source == Target) return;
12649   if (Target->isDependentType()) return;
12650 
12651   // If the conversion context location is invalid don't complain. We also
12652   // don't want to emit a warning if the issue occurs from the expansion of
12653   // a system macro. The problem is that 'getSpellingLoc()' is slow, so we
12654   // delay this check as long as possible. Once we detect we are in that
12655   // scenario, we just return.
12656   if (CC.isInvalid())
12657     return;
12658 
12659   if (Source->isAtomicType())
12660     S.Diag(E->getExprLoc(), diag::warn_atomic_implicit_seq_cst);
12661 
12662   // Diagnose implicit casts to bool.
12663   if (Target->isSpecificBuiltinType(BuiltinType::Bool)) {
12664     if (isa<StringLiteral>(E))
12665       // Warn on string literal to bool.  Checks for string literals in logical
12666       // and expressions, for instance, assert(0 && "error here"), are
12667       // prevented by a check in AnalyzeImplicitConversions().
12668       return DiagnoseImpCast(S, E, T, CC,
12669                              diag::warn_impcast_string_literal_to_bool);
12670     if (isa<ObjCStringLiteral>(E) || isa<ObjCArrayLiteral>(E) ||
12671         isa<ObjCDictionaryLiteral>(E) || isa<ObjCBoxedExpr>(E)) {
12672       // This covers the literal expressions that evaluate to Objective-C
12673       // objects.
12674       return DiagnoseImpCast(S, E, T, CC,
12675                              diag::warn_impcast_objective_c_literal_to_bool);
12676     }
12677     if (Source->isPointerType() || Source->canDecayToPointerType()) {
12678       // Warn on pointer to bool conversion that is always true.
12679       S.DiagnoseAlwaysNonNullPointer(E, Expr::NPCK_NotNull, /*IsEqual*/ false,
12680                                      SourceRange(CC));
12681     }
12682   }
12683 
12684   // If the we're converting a constant to an ObjC BOOL on a platform where BOOL
12685   // is a typedef for signed char (macOS), then that constant value has to be 1
12686   // or 0.
12687   if (isObjCSignedCharBool(S, T) && Source->isIntegralType(S.Context)) {
12688     Expr::EvalResult Result;
12689     if (E->EvaluateAsInt(Result, S.getASTContext(),
12690                          Expr::SE_AllowSideEffects)) {
12691       if (Result.Val.getInt() != 1 && Result.Val.getInt() != 0) {
12692         adornObjCBoolConversionDiagWithTernaryFixit(
12693             S, E,
12694             S.Diag(CC, diag::warn_impcast_constant_value_to_objc_bool)
12695                 << toString(Result.Val.getInt(), 10));
12696       }
12697       return;
12698     }
12699   }
12700 
12701   // Check implicit casts from Objective-C collection literals to specialized
12702   // collection types, e.g., NSArray<NSString *> *.
12703   if (auto *ArrayLiteral = dyn_cast<ObjCArrayLiteral>(E))
12704     checkObjCArrayLiteral(S, QualType(Target, 0), ArrayLiteral);
12705   else if (auto *DictionaryLiteral = dyn_cast<ObjCDictionaryLiteral>(E))
12706     checkObjCDictionaryLiteral(S, QualType(Target, 0), DictionaryLiteral);
12707 
12708   // Strip vector types.
12709   if (isa<VectorType>(Source)) {
12710     if (Target->isVLSTBuiltinType() &&
12711         (S.Context.areCompatibleSveTypes(QualType(Target, 0),
12712                                          QualType(Source, 0)) ||
12713          S.Context.areLaxCompatibleSveTypes(QualType(Target, 0),
12714                                             QualType(Source, 0))))
12715       return;
12716 
12717     if (!isa<VectorType>(Target)) {
12718       if (S.SourceMgr.isInSystemMacro(CC))
12719         return;
12720       return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_vector_scalar);
12721     }
12722 
12723     // If the vector cast is cast between two vectors of the same size, it is
12724     // a bitcast, not a conversion.
12725     if (S.Context.getTypeSize(Source) == S.Context.getTypeSize(Target))
12726       return;
12727 
12728     Source = cast<VectorType>(Source)->getElementType().getTypePtr();
12729     Target = cast<VectorType>(Target)->getElementType().getTypePtr();
12730   }
12731   if (auto VecTy = dyn_cast<VectorType>(Target))
12732     Target = VecTy->getElementType().getTypePtr();
12733 
12734   // Strip complex types.
12735   if (isa<ComplexType>(Source)) {
12736     if (!isa<ComplexType>(Target)) {
12737       if (S.SourceMgr.isInSystemMacro(CC) || Target->isBooleanType())
12738         return;
12739 
12740       return DiagnoseImpCast(S, E, T, CC,
12741                              S.getLangOpts().CPlusPlus
12742                                  ? diag::err_impcast_complex_scalar
12743                                  : diag::warn_impcast_complex_scalar);
12744     }
12745 
12746     Source = cast<ComplexType>(Source)->getElementType().getTypePtr();
12747     Target = cast<ComplexType>(Target)->getElementType().getTypePtr();
12748   }
12749 
12750   const BuiltinType *SourceBT = dyn_cast<BuiltinType>(Source);
12751   const BuiltinType *TargetBT = dyn_cast<BuiltinType>(Target);
12752 
12753   // If the source is floating point...
12754   if (SourceBT && SourceBT->isFloatingPoint()) {
12755     // ...and the target is floating point...
12756     if (TargetBT && TargetBT->isFloatingPoint()) {
12757       // ...then warn if we're dropping FP rank.
12758 
12759       int Order = S.getASTContext().getFloatingTypeSemanticOrder(
12760           QualType(SourceBT, 0), QualType(TargetBT, 0));
12761       if (Order > 0) {
12762         // Don't warn about float constants that are precisely
12763         // representable in the target type.
12764         Expr::EvalResult result;
12765         if (E->EvaluateAsRValue(result, S.Context)) {
12766           // Value might be a float, a float vector, or a float complex.
12767           if (IsSameFloatAfterCast(result.Val,
12768                    S.Context.getFloatTypeSemantics(QualType(TargetBT, 0)),
12769                    S.Context.getFloatTypeSemantics(QualType(SourceBT, 0))))
12770             return;
12771         }
12772 
12773         if (S.SourceMgr.isInSystemMacro(CC))
12774           return;
12775 
12776         DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_float_precision);
12777       }
12778       // ... or possibly if we're increasing rank, too
12779       else if (Order < 0) {
12780         if (S.SourceMgr.isInSystemMacro(CC))
12781           return;
12782 
12783         DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_double_promotion);
12784       }
12785       return;
12786     }
12787 
12788     // If the target is integral, always warn.
12789     if (TargetBT && TargetBT->isInteger()) {
12790       if (S.SourceMgr.isInSystemMacro(CC))
12791         return;
12792 
12793       DiagnoseFloatingImpCast(S, E, T, CC);
12794     }
12795 
12796     // Detect the case where a call result is converted from floating-point to
12797     // to bool, and the final argument to the call is converted from bool, to
12798     // discover this typo:
12799     //
12800     //    bool b = fabs(x < 1.0);  // should be "bool b = fabs(x) < 1.0;"
12801     //
12802     // FIXME: This is an incredibly special case; is there some more general
12803     // way to detect this class of misplaced-parentheses bug?
12804     if (Target->isBooleanType() && isa<CallExpr>(E)) {
12805       // Check last argument of function call to see if it is an
12806       // implicit cast from a type matching the type the result
12807       // is being cast to.
12808       CallExpr *CEx = cast<CallExpr>(E);
12809       if (unsigned NumArgs = CEx->getNumArgs()) {
12810         Expr *LastA = CEx->getArg(NumArgs - 1);
12811         Expr *InnerE = LastA->IgnoreParenImpCasts();
12812         if (isa<ImplicitCastExpr>(LastA) &&
12813             InnerE->getType()->isBooleanType()) {
12814           // Warn on this floating-point to bool conversion
12815           DiagnoseImpCast(S, E, T, CC,
12816                           diag::warn_impcast_floating_point_to_bool);
12817         }
12818       }
12819     }
12820     return;
12821   }
12822 
12823   // Valid casts involving fixed point types should be accounted for here.
12824   if (Source->isFixedPointType()) {
12825     if (Target->isUnsaturatedFixedPointType()) {
12826       Expr::EvalResult Result;
12827       if (E->EvaluateAsFixedPoint(Result, S.Context, Expr::SE_AllowSideEffects,
12828                                   S.isConstantEvaluated())) {
12829         llvm::APFixedPoint Value = Result.Val.getFixedPoint();
12830         llvm::APFixedPoint MaxVal = S.Context.getFixedPointMax(T);
12831         llvm::APFixedPoint MinVal = S.Context.getFixedPointMin(T);
12832         if (Value > MaxVal || Value < MinVal) {
12833           S.DiagRuntimeBehavior(E->getExprLoc(), E,
12834                                 S.PDiag(diag::warn_impcast_fixed_point_range)
12835                                     << Value.toString() << T
12836                                     << E->getSourceRange()
12837                                     << clang::SourceRange(CC));
12838           return;
12839         }
12840       }
12841     } else if (Target->isIntegerType()) {
12842       Expr::EvalResult Result;
12843       if (!S.isConstantEvaluated() &&
12844           E->EvaluateAsFixedPoint(Result, S.Context,
12845                                   Expr::SE_AllowSideEffects)) {
12846         llvm::APFixedPoint FXResult = Result.Val.getFixedPoint();
12847 
12848         bool Overflowed;
12849         llvm::APSInt IntResult = FXResult.convertToInt(
12850             S.Context.getIntWidth(T),
12851             Target->isSignedIntegerOrEnumerationType(), &Overflowed);
12852 
12853         if (Overflowed) {
12854           S.DiagRuntimeBehavior(E->getExprLoc(), E,
12855                                 S.PDiag(diag::warn_impcast_fixed_point_range)
12856                                     << FXResult.toString() << T
12857                                     << E->getSourceRange()
12858                                     << clang::SourceRange(CC));
12859           return;
12860         }
12861       }
12862     }
12863   } else if (Target->isUnsaturatedFixedPointType()) {
12864     if (Source->isIntegerType()) {
12865       Expr::EvalResult Result;
12866       if (!S.isConstantEvaluated() &&
12867           E->EvaluateAsInt(Result, S.Context, Expr::SE_AllowSideEffects)) {
12868         llvm::APSInt Value = Result.Val.getInt();
12869 
12870         bool Overflowed;
12871         llvm::APFixedPoint IntResult = llvm::APFixedPoint::getFromIntValue(
12872             Value, S.Context.getFixedPointSemantics(T), &Overflowed);
12873 
12874         if (Overflowed) {
12875           S.DiagRuntimeBehavior(E->getExprLoc(), E,
12876                                 S.PDiag(diag::warn_impcast_fixed_point_range)
12877                                     << toString(Value, /*Radix=*/10) << T
12878                                     << E->getSourceRange()
12879                                     << clang::SourceRange(CC));
12880           return;
12881         }
12882       }
12883     }
12884   }
12885 
12886   // If we are casting an integer type to a floating point type without
12887   // initialization-list syntax, we might lose accuracy if the floating
12888   // point type has a narrower significand than the integer type.
12889   if (SourceBT && TargetBT && SourceBT->isIntegerType() &&
12890       TargetBT->isFloatingType() && !IsListInit) {
12891     // Determine the number of precision bits in the source integer type.
12892     IntRange SourceRange = GetExprRange(S.Context, E, S.isConstantEvaluated(),
12893                                         /*Approximate*/ true);
12894     unsigned int SourcePrecision = SourceRange.Width;
12895 
12896     // Determine the number of precision bits in the
12897     // target floating point type.
12898     unsigned int TargetPrecision = llvm::APFloatBase::semanticsPrecision(
12899         S.Context.getFloatTypeSemantics(QualType(TargetBT, 0)));
12900 
12901     if (SourcePrecision > 0 && TargetPrecision > 0 &&
12902         SourcePrecision > TargetPrecision) {
12903 
12904       if (Optional<llvm::APSInt> SourceInt =
12905               E->getIntegerConstantExpr(S.Context)) {
12906         // If the source integer is a constant, convert it to the target
12907         // floating point type. Issue a warning if the value changes
12908         // during the whole conversion.
12909         llvm::APFloat TargetFloatValue(
12910             S.Context.getFloatTypeSemantics(QualType(TargetBT, 0)));
12911         llvm::APFloat::opStatus ConversionStatus =
12912             TargetFloatValue.convertFromAPInt(
12913                 *SourceInt, SourceBT->isSignedInteger(),
12914                 llvm::APFloat::rmNearestTiesToEven);
12915 
12916         if (ConversionStatus != llvm::APFloat::opOK) {
12917           SmallString<32> PrettySourceValue;
12918           SourceInt->toString(PrettySourceValue, 10);
12919           SmallString<32> PrettyTargetValue;
12920           TargetFloatValue.toString(PrettyTargetValue, TargetPrecision);
12921 
12922           S.DiagRuntimeBehavior(
12923               E->getExprLoc(), E,
12924               S.PDiag(diag::warn_impcast_integer_float_precision_constant)
12925                   << PrettySourceValue << PrettyTargetValue << E->getType() << T
12926                   << E->getSourceRange() << clang::SourceRange(CC));
12927         }
12928       } else {
12929         // Otherwise, the implicit conversion may lose precision.
12930         DiagnoseImpCast(S, E, T, CC,
12931                         diag::warn_impcast_integer_float_precision);
12932       }
12933     }
12934   }
12935 
12936   DiagnoseNullConversion(S, E, T, CC);
12937 
12938   S.DiscardMisalignedMemberAddress(Target, E);
12939 
12940   if (Target->isBooleanType())
12941     DiagnoseIntInBoolContext(S, E);
12942 
12943   if (!Source->isIntegerType() || !Target->isIntegerType())
12944     return;
12945 
12946   // TODO: remove this early return once the false positives for constant->bool
12947   // in templates, macros, etc, are reduced or removed.
12948   if (Target->isSpecificBuiltinType(BuiltinType::Bool))
12949     return;
12950 
12951   if (isObjCSignedCharBool(S, T) && !Source->isCharType() &&
12952       !E->isKnownToHaveBooleanValue(/*Semantic=*/false)) {
12953     return adornObjCBoolConversionDiagWithTernaryFixit(
12954         S, E,
12955         S.Diag(CC, diag::warn_impcast_int_to_objc_signed_char_bool)
12956             << E->getType());
12957   }
12958 
12959   IntRange SourceTypeRange =
12960       IntRange::forTargetOfCanonicalType(S.Context, Source);
12961   IntRange LikelySourceRange =
12962       GetExprRange(S.Context, E, S.isConstantEvaluated(), /*Approximate*/ true);
12963   IntRange TargetRange = IntRange::forTargetOfCanonicalType(S.Context, Target);
12964 
12965   if (LikelySourceRange.Width > TargetRange.Width) {
12966     // If the source is a constant, use a default-on diagnostic.
12967     // TODO: this should happen for bitfield stores, too.
12968     Expr::EvalResult Result;
12969     if (E->EvaluateAsInt(Result, S.Context, Expr::SE_AllowSideEffects,
12970                          S.isConstantEvaluated())) {
12971       llvm::APSInt Value(32);
12972       Value = Result.Val.getInt();
12973 
12974       if (S.SourceMgr.isInSystemMacro(CC))
12975         return;
12976 
12977       std::string PrettySourceValue = toString(Value, 10);
12978       std::string PrettyTargetValue = PrettyPrintInRange(Value, TargetRange);
12979 
12980       S.DiagRuntimeBehavior(
12981           E->getExprLoc(), E,
12982           S.PDiag(diag::warn_impcast_integer_precision_constant)
12983               << PrettySourceValue << PrettyTargetValue << E->getType() << T
12984               << E->getSourceRange() << SourceRange(CC));
12985       return;
12986     }
12987 
12988     // People want to build with -Wshorten-64-to-32 and not -Wconversion.
12989     if (S.SourceMgr.isInSystemMacro(CC))
12990       return;
12991 
12992     if (TargetRange.Width == 32 && S.Context.getIntWidth(E->getType()) == 64)
12993       return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_integer_64_32,
12994                              /* pruneControlFlow */ true);
12995     return DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_integer_precision);
12996   }
12997 
12998   if (TargetRange.Width > SourceTypeRange.Width) {
12999     if (auto *UO = dyn_cast<UnaryOperator>(E))
13000       if (UO->getOpcode() == UO_Minus)
13001         if (Source->isUnsignedIntegerType()) {
13002           if (Target->isUnsignedIntegerType())
13003             return DiagnoseImpCast(S, E, T, CC,
13004                                    diag::warn_impcast_high_order_zero_bits);
13005           if (Target->isSignedIntegerType())
13006             return DiagnoseImpCast(S, E, T, CC,
13007                                    diag::warn_impcast_nonnegative_result);
13008         }
13009   }
13010 
13011   if (TargetRange.Width == LikelySourceRange.Width &&
13012       !TargetRange.NonNegative && LikelySourceRange.NonNegative &&
13013       Source->isSignedIntegerType()) {
13014     // Warn when doing a signed to signed conversion, warn if the positive
13015     // source value is exactly the width of the target type, which will
13016     // cause a negative value to be stored.
13017 
13018     Expr::EvalResult Result;
13019     if (E->EvaluateAsInt(Result, S.Context, Expr::SE_AllowSideEffects) &&
13020         !S.SourceMgr.isInSystemMacro(CC)) {
13021       llvm::APSInt Value = Result.Val.getInt();
13022       if (isSameWidthConstantConversion(S, E, T, CC)) {
13023         std::string PrettySourceValue = toString(Value, 10);
13024         std::string PrettyTargetValue = PrettyPrintInRange(Value, TargetRange);
13025 
13026         S.DiagRuntimeBehavior(
13027             E->getExprLoc(), E,
13028             S.PDiag(diag::warn_impcast_integer_precision_constant)
13029                 << PrettySourceValue << PrettyTargetValue << E->getType() << T
13030                 << E->getSourceRange() << SourceRange(CC));
13031         return;
13032       }
13033     }
13034 
13035     // Fall through for non-constants to give a sign conversion warning.
13036   }
13037 
13038   if ((TargetRange.NonNegative && !LikelySourceRange.NonNegative) ||
13039       (!TargetRange.NonNegative && LikelySourceRange.NonNegative &&
13040        LikelySourceRange.Width == TargetRange.Width)) {
13041     if (S.SourceMgr.isInSystemMacro(CC))
13042       return;
13043 
13044     unsigned DiagID = diag::warn_impcast_integer_sign;
13045 
13046     // Traditionally, gcc has warned about this under -Wsign-compare.
13047     // We also want to warn about it in -Wconversion.
13048     // So if -Wconversion is off, use a completely identical diagnostic
13049     // in the sign-compare group.
13050     // The conditional-checking code will
13051     if (ICContext) {
13052       DiagID = diag::warn_impcast_integer_sign_conditional;
13053       *ICContext = true;
13054     }
13055 
13056     return DiagnoseImpCast(S, E, T, CC, DiagID);
13057   }
13058 
13059   // Diagnose conversions between different enumeration types.
13060   // In C, we pretend that the type of an EnumConstantDecl is its enumeration
13061   // type, to give us better diagnostics.
13062   QualType SourceType = E->getType();
13063   if (!S.getLangOpts().CPlusPlus) {
13064     if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
13065       if (EnumConstantDecl *ECD = dyn_cast<EnumConstantDecl>(DRE->getDecl())) {
13066         EnumDecl *Enum = cast<EnumDecl>(ECD->getDeclContext());
13067         SourceType = S.Context.getTypeDeclType(Enum);
13068         Source = S.Context.getCanonicalType(SourceType).getTypePtr();
13069       }
13070   }
13071 
13072   if (const EnumType *SourceEnum = Source->getAs<EnumType>())
13073     if (const EnumType *TargetEnum = Target->getAs<EnumType>())
13074       if (SourceEnum->getDecl()->hasNameForLinkage() &&
13075           TargetEnum->getDecl()->hasNameForLinkage() &&
13076           SourceEnum != TargetEnum) {
13077         if (S.SourceMgr.isInSystemMacro(CC))
13078           return;
13079 
13080         return DiagnoseImpCast(S, E, SourceType, T, CC,
13081                                diag::warn_impcast_different_enum_types);
13082       }
13083 }
13084 
13085 static void CheckConditionalOperator(Sema &S, AbstractConditionalOperator *E,
13086                                      SourceLocation CC, QualType T);
13087 
13088 static void CheckConditionalOperand(Sema &S, Expr *E, QualType T,
13089                                     SourceLocation CC, bool &ICContext) {
13090   E = E->IgnoreParenImpCasts();
13091 
13092   if (auto *CO = dyn_cast<AbstractConditionalOperator>(E))
13093     return CheckConditionalOperator(S, CO, CC, T);
13094 
13095   AnalyzeImplicitConversions(S, E, CC);
13096   if (E->getType() != T)
13097     return CheckImplicitConversion(S, E, T, CC, &ICContext);
13098 }
13099 
13100 static void CheckConditionalOperator(Sema &S, AbstractConditionalOperator *E,
13101                                      SourceLocation CC, QualType T) {
13102   AnalyzeImplicitConversions(S, E->getCond(), E->getQuestionLoc());
13103 
13104   Expr *TrueExpr = E->getTrueExpr();
13105   if (auto *BCO = dyn_cast<BinaryConditionalOperator>(E))
13106     TrueExpr = BCO->getCommon();
13107 
13108   bool Suspicious = false;
13109   CheckConditionalOperand(S, TrueExpr, T, CC, Suspicious);
13110   CheckConditionalOperand(S, E->getFalseExpr(), T, CC, Suspicious);
13111 
13112   if (T->isBooleanType())
13113     DiagnoseIntInBoolContext(S, E);
13114 
13115   // If -Wconversion would have warned about either of the candidates
13116   // for a signedness conversion to the context type...
13117   if (!Suspicious) return;
13118 
13119   // ...but it's currently ignored...
13120   if (!S.Diags.isIgnored(diag::warn_impcast_integer_sign_conditional, CC))
13121     return;
13122 
13123   // ...then check whether it would have warned about either of the
13124   // candidates for a signedness conversion to the condition type.
13125   if (E->getType() == T) return;
13126 
13127   Suspicious = false;
13128   CheckImplicitConversion(S, TrueExpr->IgnoreParenImpCasts(),
13129                           E->getType(), CC, &Suspicious);
13130   if (!Suspicious)
13131     CheckImplicitConversion(S, E->getFalseExpr()->IgnoreParenImpCasts(),
13132                             E->getType(), CC, &Suspicious);
13133 }
13134 
13135 /// Check conversion of given expression to boolean.
13136 /// Input argument E is a logical expression.
13137 static void CheckBoolLikeConversion(Sema &S, Expr *E, SourceLocation CC) {
13138   if (S.getLangOpts().Bool)
13139     return;
13140   if (E->IgnoreParenImpCasts()->getType()->isAtomicType())
13141     return;
13142   CheckImplicitConversion(S, E->IgnoreParenImpCasts(), S.Context.BoolTy, CC);
13143 }
13144 
13145 namespace {
13146 struct AnalyzeImplicitConversionsWorkItem {
13147   Expr *E;
13148   SourceLocation CC;
13149   bool IsListInit;
13150 };
13151 }
13152 
13153 /// Data recursive variant of AnalyzeImplicitConversions. Subexpressions
13154 /// that should be visited are added to WorkList.
13155 static void AnalyzeImplicitConversions(
13156     Sema &S, AnalyzeImplicitConversionsWorkItem Item,
13157     llvm::SmallVectorImpl<AnalyzeImplicitConversionsWorkItem> &WorkList) {
13158   Expr *OrigE = Item.E;
13159   SourceLocation CC = Item.CC;
13160 
13161   QualType T = OrigE->getType();
13162   Expr *E = OrigE->IgnoreParenImpCasts();
13163 
13164   // Propagate whether we are in a C++ list initialization expression.
13165   // If so, we do not issue warnings for implicit int-float conversion
13166   // precision loss, because C++11 narrowing already handles it.
13167   bool IsListInit = Item.IsListInit ||
13168                     (isa<InitListExpr>(OrigE) && S.getLangOpts().CPlusPlus);
13169 
13170   if (E->isTypeDependent() || E->isValueDependent())
13171     return;
13172 
13173   Expr *SourceExpr = E;
13174   // Examine, but don't traverse into the source expression of an
13175   // OpaqueValueExpr, since it may have multiple parents and we don't want to
13176   // emit duplicate diagnostics. Its fine to examine the form or attempt to
13177   // evaluate it in the context of checking the specific conversion to T though.
13178   if (auto *OVE = dyn_cast<OpaqueValueExpr>(E))
13179     if (auto *Src = OVE->getSourceExpr())
13180       SourceExpr = Src;
13181 
13182   if (const auto *UO = dyn_cast<UnaryOperator>(SourceExpr))
13183     if (UO->getOpcode() == UO_Not &&
13184         UO->getSubExpr()->isKnownToHaveBooleanValue())
13185       S.Diag(UO->getBeginLoc(), diag::warn_bitwise_negation_bool)
13186           << OrigE->getSourceRange() << T->isBooleanType()
13187           << FixItHint::CreateReplacement(UO->getBeginLoc(), "!");
13188 
13189   // For conditional operators, we analyze the arguments as if they
13190   // were being fed directly into the output.
13191   if (auto *CO = dyn_cast<AbstractConditionalOperator>(SourceExpr)) {
13192     CheckConditionalOperator(S, CO, CC, T);
13193     return;
13194   }
13195 
13196   // Check implicit argument conversions for function calls.
13197   if (CallExpr *Call = dyn_cast<CallExpr>(SourceExpr))
13198     CheckImplicitArgumentConversions(S, Call, CC);
13199 
13200   // Go ahead and check any implicit conversions we might have skipped.
13201   // The non-canonical typecheck is just an optimization;
13202   // CheckImplicitConversion will filter out dead implicit conversions.
13203   if (SourceExpr->getType() != T)
13204     CheckImplicitConversion(S, SourceExpr, T, CC, nullptr, IsListInit);
13205 
13206   // Now continue drilling into this expression.
13207 
13208   if (PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E)) {
13209     // The bound subexpressions in a PseudoObjectExpr are not reachable
13210     // as transitive children.
13211     // FIXME: Use a more uniform representation for this.
13212     for (auto *SE : POE->semantics())
13213       if (auto *OVE = dyn_cast<OpaqueValueExpr>(SE))
13214         WorkList.push_back({OVE->getSourceExpr(), CC, IsListInit});
13215   }
13216 
13217   // Skip past explicit casts.
13218   if (auto *CE = dyn_cast<ExplicitCastExpr>(E)) {
13219     E = CE->getSubExpr()->IgnoreParenImpCasts();
13220     if (!CE->getType()->isVoidType() && E->getType()->isAtomicType())
13221       S.Diag(E->getBeginLoc(), diag::warn_atomic_implicit_seq_cst);
13222     WorkList.push_back({E, CC, IsListInit});
13223     return;
13224   }
13225 
13226   if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
13227     // Do a somewhat different check with comparison operators.
13228     if (BO->isComparisonOp())
13229       return AnalyzeComparison(S, BO);
13230 
13231     // And with simple assignments.
13232     if (BO->getOpcode() == BO_Assign)
13233       return AnalyzeAssignment(S, BO);
13234     // And with compound assignments.
13235     if (BO->isAssignmentOp())
13236       return AnalyzeCompoundAssignment(S, BO);
13237   }
13238 
13239   // These break the otherwise-useful invariant below.  Fortunately,
13240   // we don't really need to recurse into them, because any internal
13241   // expressions should have been analyzed already when they were
13242   // built into statements.
13243   if (isa<StmtExpr>(E)) return;
13244 
13245   // Don't descend into unevaluated contexts.
13246   if (isa<UnaryExprOrTypeTraitExpr>(E)) return;
13247 
13248   // Now just recurse over the expression's children.
13249   CC = E->getExprLoc();
13250   BinaryOperator *BO = dyn_cast<BinaryOperator>(E);
13251   bool IsLogicalAndOperator = BO && BO->getOpcode() == BO_LAnd;
13252   for (Stmt *SubStmt : E->children()) {
13253     Expr *ChildExpr = dyn_cast_or_null<Expr>(SubStmt);
13254     if (!ChildExpr)
13255       continue;
13256 
13257     if (IsLogicalAndOperator &&
13258         isa<StringLiteral>(ChildExpr->IgnoreParenImpCasts()))
13259       // Ignore checking string literals that are in logical and operators.
13260       // This is a common pattern for asserts.
13261       continue;
13262     WorkList.push_back({ChildExpr, CC, IsListInit});
13263   }
13264 
13265   if (BO && BO->isLogicalOp()) {
13266     Expr *SubExpr = BO->getLHS()->IgnoreParenImpCasts();
13267     if (!IsLogicalAndOperator || !isa<StringLiteral>(SubExpr))
13268       ::CheckBoolLikeConversion(S, SubExpr, BO->getExprLoc());
13269 
13270     SubExpr = BO->getRHS()->IgnoreParenImpCasts();
13271     if (!IsLogicalAndOperator || !isa<StringLiteral>(SubExpr))
13272       ::CheckBoolLikeConversion(S, SubExpr, BO->getExprLoc());
13273   }
13274 
13275   if (const UnaryOperator *U = dyn_cast<UnaryOperator>(E)) {
13276     if (U->getOpcode() == UO_LNot) {
13277       ::CheckBoolLikeConversion(S, U->getSubExpr(), CC);
13278     } else if (U->getOpcode() != UO_AddrOf) {
13279       if (U->getSubExpr()->getType()->isAtomicType())
13280         S.Diag(U->getSubExpr()->getBeginLoc(),
13281                diag::warn_atomic_implicit_seq_cst);
13282     }
13283   }
13284 }
13285 
13286 /// AnalyzeImplicitConversions - Find and report any interesting
13287 /// implicit conversions in the given expression.  There are a couple
13288 /// of competing diagnostics here, -Wconversion and -Wsign-compare.
13289 static void AnalyzeImplicitConversions(Sema &S, Expr *OrigE, SourceLocation CC,
13290                                        bool IsListInit/*= false*/) {
13291   llvm::SmallVector<AnalyzeImplicitConversionsWorkItem, 16> WorkList;
13292   WorkList.push_back({OrigE, CC, IsListInit});
13293   while (!WorkList.empty())
13294     AnalyzeImplicitConversions(S, WorkList.pop_back_val(), WorkList);
13295 }
13296 
13297 /// Diagnose integer type and any valid implicit conversion to it.
13298 static bool checkOpenCLEnqueueIntType(Sema &S, Expr *E, const QualType &IntT) {
13299   // Taking into account implicit conversions,
13300   // allow any integer.
13301   if (!E->getType()->isIntegerType()) {
13302     S.Diag(E->getBeginLoc(),
13303            diag::err_opencl_enqueue_kernel_invalid_local_size_type);
13304     return true;
13305   }
13306   // Potentially emit standard warnings for implicit conversions if enabled
13307   // using -Wconversion.
13308   CheckImplicitConversion(S, E, IntT, E->getBeginLoc());
13309   return false;
13310 }
13311 
13312 // Helper function for Sema::DiagnoseAlwaysNonNullPointer.
13313 // Returns true when emitting a warning about taking the address of a reference.
13314 static bool CheckForReference(Sema &SemaRef, const Expr *E,
13315                               const PartialDiagnostic &PD) {
13316   E = E->IgnoreParenImpCasts();
13317 
13318   const FunctionDecl *FD = nullptr;
13319 
13320   if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
13321     if (!DRE->getDecl()->getType()->isReferenceType())
13322       return false;
13323   } else if (const MemberExpr *M = dyn_cast<MemberExpr>(E)) {
13324     if (!M->getMemberDecl()->getType()->isReferenceType())
13325       return false;
13326   } else if (const CallExpr *Call = dyn_cast<CallExpr>(E)) {
13327     if (!Call->getCallReturnType(SemaRef.Context)->isReferenceType())
13328       return false;
13329     FD = Call->getDirectCallee();
13330   } else {
13331     return false;
13332   }
13333 
13334   SemaRef.Diag(E->getExprLoc(), PD);
13335 
13336   // If possible, point to location of function.
13337   if (FD) {
13338     SemaRef.Diag(FD->getLocation(), diag::note_reference_is_return_value) << FD;
13339   }
13340 
13341   return true;
13342 }
13343 
13344 // Returns true if the SourceLocation is expanded from any macro body.
13345 // Returns false if the SourceLocation is invalid, is from not in a macro
13346 // expansion, or is from expanded from a top-level macro argument.
13347 static bool IsInAnyMacroBody(const SourceManager &SM, SourceLocation Loc) {
13348   if (Loc.isInvalid())
13349     return false;
13350 
13351   while (Loc.isMacroID()) {
13352     if (SM.isMacroBodyExpansion(Loc))
13353       return true;
13354     Loc = SM.getImmediateMacroCallerLoc(Loc);
13355   }
13356 
13357   return false;
13358 }
13359 
13360 /// Diagnose pointers that are always non-null.
13361 /// \param E the expression containing the pointer
13362 /// \param NullKind NPCK_NotNull if E is a cast to bool, otherwise, E is
13363 /// compared to a null pointer
13364 /// \param IsEqual True when the comparison is equal to a null pointer
13365 /// \param Range Extra SourceRange to highlight in the diagnostic
13366 void Sema::DiagnoseAlwaysNonNullPointer(Expr *E,
13367                                         Expr::NullPointerConstantKind NullKind,
13368                                         bool IsEqual, SourceRange Range) {
13369   if (!E)
13370     return;
13371 
13372   // Don't warn inside macros.
13373   if (E->getExprLoc().isMacroID()) {
13374     const SourceManager &SM = getSourceManager();
13375     if (IsInAnyMacroBody(SM, E->getExprLoc()) ||
13376         IsInAnyMacroBody(SM, Range.getBegin()))
13377       return;
13378   }
13379   E = E->IgnoreImpCasts();
13380 
13381   const bool IsCompare = NullKind != Expr::NPCK_NotNull;
13382 
13383   if (isa<CXXThisExpr>(E)) {
13384     unsigned DiagID = IsCompare ? diag::warn_this_null_compare
13385                                 : diag::warn_this_bool_conversion;
13386     Diag(E->getExprLoc(), DiagID) << E->getSourceRange() << Range << IsEqual;
13387     return;
13388   }
13389 
13390   bool IsAddressOf = false;
13391 
13392   if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
13393     if (UO->getOpcode() != UO_AddrOf)
13394       return;
13395     IsAddressOf = true;
13396     E = UO->getSubExpr();
13397   }
13398 
13399   if (IsAddressOf) {
13400     unsigned DiagID = IsCompare
13401                           ? diag::warn_address_of_reference_null_compare
13402                           : diag::warn_address_of_reference_bool_conversion;
13403     PartialDiagnostic PD = PDiag(DiagID) << E->getSourceRange() << Range
13404                                          << IsEqual;
13405     if (CheckForReference(*this, E, PD)) {
13406       return;
13407     }
13408   }
13409 
13410   auto ComplainAboutNonnullParamOrCall = [&](const Attr *NonnullAttr) {
13411     bool IsParam = isa<NonNullAttr>(NonnullAttr);
13412     std::string Str;
13413     llvm::raw_string_ostream S(Str);
13414     E->printPretty(S, nullptr, getPrintingPolicy());
13415     unsigned DiagID = IsCompare ? diag::warn_nonnull_expr_compare
13416                                 : diag::warn_cast_nonnull_to_bool;
13417     Diag(E->getExprLoc(), DiagID) << IsParam << S.str()
13418       << E->getSourceRange() << Range << IsEqual;
13419     Diag(NonnullAttr->getLocation(), diag::note_declared_nonnull) << IsParam;
13420   };
13421 
13422   // If we have a CallExpr that is tagged with returns_nonnull, we can complain.
13423   if (auto *Call = dyn_cast<CallExpr>(E->IgnoreParenImpCasts())) {
13424     if (auto *Callee = Call->getDirectCallee()) {
13425       if (const Attr *A = Callee->getAttr<ReturnsNonNullAttr>()) {
13426         ComplainAboutNonnullParamOrCall(A);
13427         return;
13428       }
13429     }
13430   }
13431 
13432   // Expect to find a single Decl.  Skip anything more complicated.
13433   ValueDecl *D = nullptr;
13434   if (DeclRefExpr *R = dyn_cast<DeclRefExpr>(E)) {
13435     D = R->getDecl();
13436   } else if (MemberExpr *M = dyn_cast<MemberExpr>(E)) {
13437     D = M->getMemberDecl();
13438   }
13439 
13440   // Weak Decls can be null.
13441   if (!D || D->isWeak())
13442     return;
13443 
13444   // Check for parameter decl with nonnull attribute
13445   if (const auto* PV = dyn_cast<ParmVarDecl>(D)) {
13446     if (getCurFunction() &&
13447         !getCurFunction()->ModifiedNonNullParams.count(PV)) {
13448       if (const Attr *A = PV->getAttr<NonNullAttr>()) {
13449         ComplainAboutNonnullParamOrCall(A);
13450         return;
13451       }
13452 
13453       if (const auto *FD = dyn_cast<FunctionDecl>(PV->getDeclContext())) {
13454         // Skip function template not specialized yet.
13455         if (FD->getTemplatedKind() == FunctionDecl::TK_FunctionTemplate)
13456           return;
13457         auto ParamIter = llvm::find(FD->parameters(), PV);
13458         assert(ParamIter != FD->param_end());
13459         unsigned ParamNo = std::distance(FD->param_begin(), ParamIter);
13460 
13461         for (const auto *NonNull : FD->specific_attrs<NonNullAttr>()) {
13462           if (!NonNull->args_size()) {
13463               ComplainAboutNonnullParamOrCall(NonNull);
13464               return;
13465           }
13466 
13467           for (const ParamIdx &ArgNo : NonNull->args()) {
13468             if (ArgNo.getASTIndex() == ParamNo) {
13469               ComplainAboutNonnullParamOrCall(NonNull);
13470               return;
13471             }
13472           }
13473         }
13474       }
13475     }
13476   }
13477 
13478   QualType T = D->getType();
13479   const bool IsArray = T->isArrayType();
13480   const bool IsFunction = T->isFunctionType();
13481 
13482   // Address of function is used to silence the function warning.
13483   if (IsAddressOf && IsFunction) {
13484     return;
13485   }
13486 
13487   // Found nothing.
13488   if (!IsAddressOf && !IsFunction && !IsArray)
13489     return;
13490 
13491   // Pretty print the expression for the diagnostic.
13492   std::string Str;
13493   llvm::raw_string_ostream S(Str);
13494   E->printPretty(S, nullptr, getPrintingPolicy());
13495 
13496   unsigned DiagID = IsCompare ? diag::warn_null_pointer_compare
13497                               : diag::warn_impcast_pointer_to_bool;
13498   enum {
13499     AddressOf,
13500     FunctionPointer,
13501     ArrayPointer
13502   } DiagType;
13503   if (IsAddressOf)
13504     DiagType = AddressOf;
13505   else if (IsFunction)
13506     DiagType = FunctionPointer;
13507   else if (IsArray)
13508     DiagType = ArrayPointer;
13509   else
13510     llvm_unreachable("Could not determine diagnostic.");
13511   Diag(E->getExprLoc(), DiagID) << DiagType << S.str() << E->getSourceRange()
13512                                 << Range << IsEqual;
13513 
13514   if (!IsFunction)
13515     return;
13516 
13517   // Suggest '&' to silence the function warning.
13518   Diag(E->getExprLoc(), diag::note_function_warning_silence)
13519       << FixItHint::CreateInsertion(E->getBeginLoc(), "&");
13520 
13521   // Check to see if '()' fixit should be emitted.
13522   QualType ReturnType;
13523   UnresolvedSet<4> NonTemplateOverloads;
13524   tryExprAsCall(*E, ReturnType, NonTemplateOverloads);
13525   if (ReturnType.isNull())
13526     return;
13527 
13528   if (IsCompare) {
13529     // There are two cases here.  If there is null constant, the only suggest
13530     // for a pointer return type.  If the null is 0, then suggest if the return
13531     // type is a pointer or an integer type.
13532     if (!ReturnType->isPointerType()) {
13533       if (NullKind == Expr::NPCK_ZeroExpression ||
13534           NullKind == Expr::NPCK_ZeroLiteral) {
13535         if (!ReturnType->isIntegerType())
13536           return;
13537       } else {
13538         return;
13539       }
13540     }
13541   } else { // !IsCompare
13542     // For function to bool, only suggest if the function pointer has bool
13543     // return type.
13544     if (!ReturnType->isSpecificBuiltinType(BuiltinType::Bool))
13545       return;
13546   }
13547   Diag(E->getExprLoc(), diag::note_function_to_function_call)
13548       << FixItHint::CreateInsertion(getLocForEndOfToken(E->getEndLoc()), "()");
13549 }
13550 
13551 /// Diagnoses "dangerous" implicit conversions within the given
13552 /// expression (which is a full expression).  Implements -Wconversion
13553 /// and -Wsign-compare.
13554 ///
13555 /// \param CC the "context" location of the implicit conversion, i.e.
13556 ///   the most location of the syntactic entity requiring the implicit
13557 ///   conversion
13558 void Sema::CheckImplicitConversions(Expr *E, SourceLocation CC) {
13559   // Don't diagnose in unevaluated contexts.
13560   if (isUnevaluatedContext())
13561     return;
13562 
13563   // Don't diagnose for value- or type-dependent expressions.
13564   if (E->isTypeDependent() || E->isValueDependent())
13565     return;
13566 
13567   // Check for array bounds violations in cases where the check isn't triggered
13568   // elsewhere for other Expr types (like BinaryOperators), e.g. when an
13569   // ArraySubscriptExpr is on the RHS of a variable initialization.
13570   CheckArrayAccess(E);
13571 
13572   // This is not the right CC for (e.g.) a variable initialization.
13573   AnalyzeImplicitConversions(*this, E, CC);
13574 }
13575 
13576 /// CheckBoolLikeConversion - Check conversion of given expression to boolean.
13577 /// Input argument E is a logical expression.
13578 void Sema::CheckBoolLikeConversion(Expr *E, SourceLocation CC) {
13579   ::CheckBoolLikeConversion(*this, E, CC);
13580 }
13581 
13582 /// Diagnose when expression is an integer constant expression and its evaluation
13583 /// results in integer overflow
13584 void Sema::CheckForIntOverflow (Expr *E) {
13585   // Use a work list to deal with nested struct initializers.
13586   SmallVector<Expr *, 2> Exprs(1, E);
13587 
13588   do {
13589     Expr *OriginalE = Exprs.pop_back_val();
13590     Expr *E = OriginalE->IgnoreParenCasts();
13591 
13592     if (isa<BinaryOperator>(E)) {
13593       E->EvaluateForOverflow(Context);
13594       continue;
13595     }
13596 
13597     if (auto InitList = dyn_cast<InitListExpr>(OriginalE))
13598       Exprs.append(InitList->inits().begin(), InitList->inits().end());
13599     else if (isa<ObjCBoxedExpr>(OriginalE))
13600       E->EvaluateForOverflow(Context);
13601     else if (auto Call = dyn_cast<CallExpr>(E))
13602       Exprs.append(Call->arg_begin(), Call->arg_end());
13603     else if (auto Message = dyn_cast<ObjCMessageExpr>(E))
13604       Exprs.append(Message->arg_begin(), Message->arg_end());
13605   } while (!Exprs.empty());
13606 }
13607 
13608 namespace {
13609 
13610 /// Visitor for expressions which looks for unsequenced operations on the
13611 /// same object.
13612 class SequenceChecker : public ConstEvaluatedExprVisitor<SequenceChecker> {
13613   using Base = ConstEvaluatedExprVisitor<SequenceChecker>;
13614 
13615   /// A tree of sequenced regions within an expression. Two regions are
13616   /// unsequenced if one is an ancestor or a descendent of the other. When we
13617   /// finish processing an expression with sequencing, such as a comma
13618   /// expression, we fold its tree nodes into its parent, since they are
13619   /// unsequenced with respect to nodes we will visit later.
13620   class SequenceTree {
13621     struct Value {
13622       explicit Value(unsigned Parent) : Parent(Parent), Merged(false) {}
13623       unsigned Parent : 31;
13624       unsigned Merged : 1;
13625     };
13626     SmallVector<Value, 8> Values;
13627 
13628   public:
13629     /// A region within an expression which may be sequenced with respect
13630     /// to some other region.
13631     class Seq {
13632       friend class SequenceTree;
13633 
13634       unsigned Index;
13635 
13636       explicit Seq(unsigned N) : Index(N) {}
13637 
13638     public:
13639       Seq() : Index(0) {}
13640     };
13641 
13642     SequenceTree() { Values.push_back(Value(0)); }
13643     Seq root() const { return Seq(0); }
13644 
13645     /// Create a new sequence of operations, which is an unsequenced
13646     /// subset of \p Parent. This sequence of operations is sequenced with
13647     /// respect to other children of \p Parent.
13648     Seq allocate(Seq Parent) {
13649       Values.push_back(Value(Parent.Index));
13650       return Seq(Values.size() - 1);
13651     }
13652 
13653     /// Merge a sequence of operations into its parent.
13654     void merge(Seq S) {
13655       Values[S.Index].Merged = true;
13656     }
13657 
13658     /// Determine whether two operations are unsequenced. This operation
13659     /// is asymmetric: \p Cur should be the more recent sequence, and \p Old
13660     /// should have been merged into its parent as appropriate.
13661     bool isUnsequenced(Seq Cur, Seq Old) {
13662       unsigned C = representative(Cur.Index);
13663       unsigned Target = representative(Old.Index);
13664       while (C >= Target) {
13665         if (C == Target)
13666           return true;
13667         C = Values[C].Parent;
13668       }
13669       return false;
13670     }
13671 
13672   private:
13673     /// Pick a representative for a sequence.
13674     unsigned representative(unsigned K) {
13675       if (Values[K].Merged)
13676         // Perform path compression as we go.
13677         return Values[K].Parent = representative(Values[K].Parent);
13678       return K;
13679     }
13680   };
13681 
13682   /// An object for which we can track unsequenced uses.
13683   using Object = const NamedDecl *;
13684 
13685   /// Different flavors of object usage which we track. We only track the
13686   /// least-sequenced usage of each kind.
13687   enum UsageKind {
13688     /// A read of an object. Multiple unsequenced reads are OK.
13689     UK_Use,
13690 
13691     /// A modification of an object which is sequenced before the value
13692     /// computation of the expression, such as ++n in C++.
13693     UK_ModAsValue,
13694 
13695     /// A modification of an object which is not sequenced before the value
13696     /// computation of the expression, such as n++.
13697     UK_ModAsSideEffect,
13698 
13699     UK_Count = UK_ModAsSideEffect + 1
13700   };
13701 
13702   /// Bundle together a sequencing region and the expression corresponding
13703   /// to a specific usage. One Usage is stored for each usage kind in UsageInfo.
13704   struct Usage {
13705     const Expr *UsageExpr;
13706     SequenceTree::Seq Seq;
13707 
13708     Usage() : UsageExpr(nullptr), Seq() {}
13709   };
13710 
13711   struct UsageInfo {
13712     Usage Uses[UK_Count];
13713 
13714     /// Have we issued a diagnostic for this object already?
13715     bool Diagnosed;
13716 
13717     UsageInfo() : Uses(), Diagnosed(false) {}
13718   };
13719   using UsageInfoMap = llvm::SmallDenseMap<Object, UsageInfo, 16>;
13720 
13721   Sema &SemaRef;
13722 
13723   /// Sequenced regions within the expression.
13724   SequenceTree Tree;
13725 
13726   /// Declaration modifications and references which we have seen.
13727   UsageInfoMap UsageMap;
13728 
13729   /// The region we are currently within.
13730   SequenceTree::Seq Region;
13731 
13732   /// Filled in with declarations which were modified as a side-effect
13733   /// (that is, post-increment operations).
13734   SmallVectorImpl<std::pair<Object, Usage>> *ModAsSideEffect = nullptr;
13735 
13736   /// Expressions to check later. We defer checking these to reduce
13737   /// stack usage.
13738   SmallVectorImpl<const Expr *> &WorkList;
13739 
13740   /// RAII object wrapping the visitation of a sequenced subexpression of an
13741   /// expression. At the end of this process, the side-effects of the evaluation
13742   /// become sequenced with respect to the value computation of the result, so
13743   /// we downgrade any UK_ModAsSideEffect within the evaluation to
13744   /// UK_ModAsValue.
13745   struct SequencedSubexpression {
13746     SequencedSubexpression(SequenceChecker &Self)
13747       : Self(Self), OldModAsSideEffect(Self.ModAsSideEffect) {
13748       Self.ModAsSideEffect = &ModAsSideEffect;
13749     }
13750 
13751     ~SequencedSubexpression() {
13752       for (const std::pair<Object, Usage> &M : llvm::reverse(ModAsSideEffect)) {
13753         // Add a new usage with usage kind UK_ModAsValue, and then restore
13754         // the previous usage with UK_ModAsSideEffect (thus clearing it if
13755         // the previous one was empty).
13756         UsageInfo &UI = Self.UsageMap[M.first];
13757         auto &SideEffectUsage = UI.Uses[UK_ModAsSideEffect];
13758         Self.addUsage(M.first, UI, SideEffectUsage.UsageExpr, UK_ModAsValue);
13759         SideEffectUsage = M.second;
13760       }
13761       Self.ModAsSideEffect = OldModAsSideEffect;
13762     }
13763 
13764     SequenceChecker &Self;
13765     SmallVector<std::pair<Object, Usage>, 4> ModAsSideEffect;
13766     SmallVectorImpl<std::pair<Object, Usage>> *OldModAsSideEffect;
13767   };
13768 
13769   /// RAII object wrapping the visitation of a subexpression which we might
13770   /// choose to evaluate as a constant. If any subexpression is evaluated and
13771   /// found to be non-constant, this allows us to suppress the evaluation of
13772   /// the outer expression.
13773   class EvaluationTracker {
13774   public:
13775     EvaluationTracker(SequenceChecker &Self)
13776         : Self(Self), Prev(Self.EvalTracker) {
13777       Self.EvalTracker = this;
13778     }
13779 
13780     ~EvaluationTracker() {
13781       Self.EvalTracker = Prev;
13782       if (Prev)
13783         Prev->EvalOK &= EvalOK;
13784     }
13785 
13786     bool evaluate(const Expr *E, bool &Result) {
13787       if (!EvalOK || E->isValueDependent())
13788         return false;
13789       EvalOK = E->EvaluateAsBooleanCondition(
13790           Result, Self.SemaRef.Context, Self.SemaRef.isConstantEvaluated());
13791       return EvalOK;
13792     }
13793 
13794   private:
13795     SequenceChecker &Self;
13796     EvaluationTracker *Prev;
13797     bool EvalOK = true;
13798   } *EvalTracker = nullptr;
13799 
13800   /// Find the object which is produced by the specified expression,
13801   /// if any.
13802   Object getObject(const Expr *E, bool Mod) const {
13803     E = E->IgnoreParenCasts();
13804     if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
13805       if (Mod && (UO->getOpcode() == UO_PreInc || UO->getOpcode() == UO_PreDec))
13806         return getObject(UO->getSubExpr(), Mod);
13807     } else if (const BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
13808       if (BO->getOpcode() == BO_Comma)
13809         return getObject(BO->getRHS(), Mod);
13810       if (Mod && BO->isAssignmentOp())
13811         return getObject(BO->getLHS(), Mod);
13812     } else if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
13813       // FIXME: Check for more interesting cases, like "x.n = ++x.n".
13814       if (isa<CXXThisExpr>(ME->getBase()->IgnoreParenCasts()))
13815         return ME->getMemberDecl();
13816     } else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
13817       // FIXME: If this is a reference, map through to its value.
13818       return DRE->getDecl();
13819     return nullptr;
13820   }
13821 
13822   /// Note that an object \p O was modified or used by an expression
13823   /// \p UsageExpr with usage kind \p UK. \p UI is the \p UsageInfo for
13824   /// the object \p O as obtained via the \p UsageMap.
13825   void addUsage(Object O, UsageInfo &UI, const Expr *UsageExpr, UsageKind UK) {
13826     // Get the old usage for the given object and usage kind.
13827     Usage &U = UI.Uses[UK];
13828     if (!U.UsageExpr || !Tree.isUnsequenced(Region, U.Seq)) {
13829       // If we have a modification as side effect and are in a sequenced
13830       // subexpression, save the old Usage so that we can restore it later
13831       // in SequencedSubexpression::~SequencedSubexpression.
13832       if (UK == UK_ModAsSideEffect && ModAsSideEffect)
13833         ModAsSideEffect->push_back(std::make_pair(O, U));
13834       // Then record the new usage with the current sequencing region.
13835       U.UsageExpr = UsageExpr;
13836       U.Seq = Region;
13837     }
13838   }
13839 
13840   /// Check whether a modification or use of an object \p O in an expression
13841   /// \p UsageExpr conflicts with a prior usage of kind \p OtherKind. \p UI is
13842   /// the \p UsageInfo for the object \p O as obtained via the \p UsageMap.
13843   /// \p IsModMod is true when we are checking for a mod-mod unsequenced
13844   /// usage and false we are checking for a mod-use unsequenced usage.
13845   void checkUsage(Object O, UsageInfo &UI, const Expr *UsageExpr,
13846                   UsageKind OtherKind, bool IsModMod) {
13847     if (UI.Diagnosed)
13848       return;
13849 
13850     const Usage &U = UI.Uses[OtherKind];
13851     if (!U.UsageExpr || !Tree.isUnsequenced(Region, U.Seq))
13852       return;
13853 
13854     const Expr *Mod = U.UsageExpr;
13855     const Expr *ModOrUse = UsageExpr;
13856     if (OtherKind == UK_Use)
13857       std::swap(Mod, ModOrUse);
13858 
13859     SemaRef.DiagRuntimeBehavior(
13860         Mod->getExprLoc(), {Mod, ModOrUse},
13861         SemaRef.PDiag(IsModMod ? diag::warn_unsequenced_mod_mod
13862                                : diag::warn_unsequenced_mod_use)
13863             << O << SourceRange(ModOrUse->getExprLoc()));
13864     UI.Diagnosed = true;
13865   }
13866 
13867   // A note on note{Pre, Post}{Use, Mod}:
13868   //
13869   // (It helps to follow the algorithm with an expression such as
13870   //  "((++k)++, k) = k" or "k = (k++, k++)". Both contain unsequenced
13871   //  operations before C++17 and both are well-defined in C++17).
13872   //
13873   // When visiting a node which uses/modify an object we first call notePreUse
13874   // or notePreMod before visiting its sub-expression(s). At this point the
13875   // children of the current node have not yet been visited and so the eventual
13876   // uses/modifications resulting from the children of the current node have not
13877   // been recorded yet.
13878   //
13879   // We then visit the children of the current node. After that notePostUse or
13880   // notePostMod is called. These will 1) detect an unsequenced modification
13881   // as side effect (as in "k++ + k") and 2) add a new usage with the
13882   // appropriate usage kind.
13883   //
13884   // We also have to be careful that some operation sequences modification as
13885   // side effect as well (for example: || or ,). To account for this we wrap
13886   // the visitation of such a sub-expression (for example: the LHS of || or ,)
13887   // with SequencedSubexpression. SequencedSubexpression is an RAII object
13888   // which record usages which are modifications as side effect, and then
13889   // downgrade them (or more accurately restore the previous usage which was a
13890   // modification as side effect) when exiting the scope of the sequenced
13891   // subexpression.
13892 
13893   void notePreUse(Object O, const Expr *UseExpr) {
13894     UsageInfo &UI = UsageMap[O];
13895     // Uses conflict with other modifications.
13896     checkUsage(O, UI, UseExpr, /*OtherKind=*/UK_ModAsValue, /*IsModMod=*/false);
13897   }
13898 
13899   void notePostUse(Object O, const Expr *UseExpr) {
13900     UsageInfo &UI = UsageMap[O];
13901     checkUsage(O, UI, UseExpr, /*OtherKind=*/UK_ModAsSideEffect,
13902                /*IsModMod=*/false);
13903     addUsage(O, UI, UseExpr, /*UsageKind=*/UK_Use);
13904   }
13905 
13906   void notePreMod(Object O, const Expr *ModExpr) {
13907     UsageInfo &UI = UsageMap[O];
13908     // Modifications conflict with other modifications and with uses.
13909     checkUsage(O, UI, ModExpr, /*OtherKind=*/UK_ModAsValue, /*IsModMod=*/true);
13910     checkUsage(O, UI, ModExpr, /*OtherKind=*/UK_Use, /*IsModMod=*/false);
13911   }
13912 
13913   void notePostMod(Object O, const Expr *ModExpr, UsageKind UK) {
13914     UsageInfo &UI = UsageMap[O];
13915     checkUsage(O, UI, ModExpr, /*OtherKind=*/UK_ModAsSideEffect,
13916                /*IsModMod=*/true);
13917     addUsage(O, UI, ModExpr, /*UsageKind=*/UK);
13918   }
13919 
13920 public:
13921   SequenceChecker(Sema &S, const Expr *E,
13922                   SmallVectorImpl<const Expr *> &WorkList)
13923       : Base(S.Context), SemaRef(S), Region(Tree.root()), WorkList(WorkList) {
13924     Visit(E);
13925     // Silence a -Wunused-private-field since WorkList is now unused.
13926     // TODO: Evaluate if it can be used, and if not remove it.
13927     (void)this->WorkList;
13928   }
13929 
13930   void VisitStmt(const Stmt *S) {
13931     // Skip all statements which aren't expressions for now.
13932   }
13933 
13934   void VisitExpr(const Expr *E) {
13935     // By default, just recurse to evaluated subexpressions.
13936     Base::VisitStmt(E);
13937   }
13938 
13939   void VisitCastExpr(const CastExpr *E) {
13940     Object O = Object();
13941     if (E->getCastKind() == CK_LValueToRValue)
13942       O = getObject(E->getSubExpr(), false);
13943 
13944     if (O)
13945       notePreUse(O, E);
13946     VisitExpr(E);
13947     if (O)
13948       notePostUse(O, E);
13949   }
13950 
13951   void VisitSequencedExpressions(const Expr *SequencedBefore,
13952                                  const Expr *SequencedAfter) {
13953     SequenceTree::Seq BeforeRegion = Tree.allocate(Region);
13954     SequenceTree::Seq AfterRegion = Tree.allocate(Region);
13955     SequenceTree::Seq OldRegion = Region;
13956 
13957     {
13958       SequencedSubexpression SeqBefore(*this);
13959       Region = BeforeRegion;
13960       Visit(SequencedBefore);
13961     }
13962 
13963     Region = AfterRegion;
13964     Visit(SequencedAfter);
13965 
13966     Region = OldRegion;
13967 
13968     Tree.merge(BeforeRegion);
13969     Tree.merge(AfterRegion);
13970   }
13971 
13972   void VisitArraySubscriptExpr(const ArraySubscriptExpr *ASE) {
13973     // C++17 [expr.sub]p1:
13974     //   The expression E1[E2] is identical (by definition) to *((E1)+(E2)). The
13975     //   expression E1 is sequenced before the expression E2.
13976     if (SemaRef.getLangOpts().CPlusPlus17)
13977       VisitSequencedExpressions(ASE->getLHS(), ASE->getRHS());
13978     else {
13979       Visit(ASE->getLHS());
13980       Visit(ASE->getRHS());
13981     }
13982   }
13983 
13984   void VisitBinPtrMemD(const BinaryOperator *BO) { VisitBinPtrMem(BO); }
13985   void VisitBinPtrMemI(const BinaryOperator *BO) { VisitBinPtrMem(BO); }
13986   void VisitBinPtrMem(const BinaryOperator *BO) {
13987     // C++17 [expr.mptr.oper]p4:
13988     //  Abbreviating pm-expression.*cast-expression as E1.*E2, [...]
13989     //  the expression E1 is sequenced before the expression E2.
13990     if (SemaRef.getLangOpts().CPlusPlus17)
13991       VisitSequencedExpressions(BO->getLHS(), BO->getRHS());
13992     else {
13993       Visit(BO->getLHS());
13994       Visit(BO->getRHS());
13995     }
13996   }
13997 
13998   void VisitBinShl(const BinaryOperator *BO) { VisitBinShlShr(BO); }
13999   void VisitBinShr(const BinaryOperator *BO) { VisitBinShlShr(BO); }
14000   void VisitBinShlShr(const BinaryOperator *BO) {
14001     // C++17 [expr.shift]p4:
14002     //  The expression E1 is sequenced before the expression E2.
14003     if (SemaRef.getLangOpts().CPlusPlus17)
14004       VisitSequencedExpressions(BO->getLHS(), BO->getRHS());
14005     else {
14006       Visit(BO->getLHS());
14007       Visit(BO->getRHS());
14008     }
14009   }
14010 
14011   void VisitBinComma(const BinaryOperator *BO) {
14012     // C++11 [expr.comma]p1:
14013     //   Every value computation and side effect associated with the left
14014     //   expression is sequenced before every value computation and side
14015     //   effect associated with the right expression.
14016     VisitSequencedExpressions(BO->getLHS(), BO->getRHS());
14017   }
14018 
14019   void VisitBinAssign(const BinaryOperator *BO) {
14020     SequenceTree::Seq RHSRegion;
14021     SequenceTree::Seq LHSRegion;
14022     if (SemaRef.getLangOpts().CPlusPlus17) {
14023       RHSRegion = Tree.allocate(Region);
14024       LHSRegion = Tree.allocate(Region);
14025     } else {
14026       RHSRegion = Region;
14027       LHSRegion = Region;
14028     }
14029     SequenceTree::Seq OldRegion = Region;
14030 
14031     // C++11 [expr.ass]p1:
14032     //  [...] the assignment is sequenced after the value computation
14033     //  of the right and left operands, [...]
14034     //
14035     // so check it before inspecting the operands and update the
14036     // map afterwards.
14037     Object O = getObject(BO->getLHS(), /*Mod=*/true);
14038     if (O)
14039       notePreMod(O, BO);
14040 
14041     if (SemaRef.getLangOpts().CPlusPlus17) {
14042       // C++17 [expr.ass]p1:
14043       //  [...] The right operand is sequenced before the left operand. [...]
14044       {
14045         SequencedSubexpression SeqBefore(*this);
14046         Region = RHSRegion;
14047         Visit(BO->getRHS());
14048       }
14049 
14050       Region = LHSRegion;
14051       Visit(BO->getLHS());
14052 
14053       if (O && isa<CompoundAssignOperator>(BO))
14054         notePostUse(O, BO);
14055 
14056     } else {
14057       // C++11 does not specify any sequencing between the LHS and RHS.
14058       Region = LHSRegion;
14059       Visit(BO->getLHS());
14060 
14061       if (O && isa<CompoundAssignOperator>(BO))
14062         notePostUse(O, BO);
14063 
14064       Region = RHSRegion;
14065       Visit(BO->getRHS());
14066     }
14067 
14068     // C++11 [expr.ass]p1:
14069     //  the assignment is sequenced [...] before the value computation of the
14070     //  assignment expression.
14071     // C11 6.5.16/3 has no such rule.
14072     Region = OldRegion;
14073     if (O)
14074       notePostMod(O, BO,
14075                   SemaRef.getLangOpts().CPlusPlus ? UK_ModAsValue
14076                                                   : UK_ModAsSideEffect);
14077     if (SemaRef.getLangOpts().CPlusPlus17) {
14078       Tree.merge(RHSRegion);
14079       Tree.merge(LHSRegion);
14080     }
14081   }
14082 
14083   void VisitCompoundAssignOperator(const CompoundAssignOperator *CAO) {
14084     VisitBinAssign(CAO);
14085   }
14086 
14087   void VisitUnaryPreInc(const UnaryOperator *UO) { VisitUnaryPreIncDec(UO); }
14088   void VisitUnaryPreDec(const UnaryOperator *UO) { VisitUnaryPreIncDec(UO); }
14089   void VisitUnaryPreIncDec(const UnaryOperator *UO) {
14090     Object O = getObject(UO->getSubExpr(), true);
14091     if (!O)
14092       return VisitExpr(UO);
14093 
14094     notePreMod(O, UO);
14095     Visit(UO->getSubExpr());
14096     // C++11 [expr.pre.incr]p1:
14097     //   the expression ++x is equivalent to x+=1
14098     notePostMod(O, UO,
14099                 SemaRef.getLangOpts().CPlusPlus ? UK_ModAsValue
14100                                                 : UK_ModAsSideEffect);
14101   }
14102 
14103   void VisitUnaryPostInc(const UnaryOperator *UO) { VisitUnaryPostIncDec(UO); }
14104   void VisitUnaryPostDec(const UnaryOperator *UO) { VisitUnaryPostIncDec(UO); }
14105   void VisitUnaryPostIncDec(const UnaryOperator *UO) {
14106     Object O = getObject(UO->getSubExpr(), true);
14107     if (!O)
14108       return VisitExpr(UO);
14109 
14110     notePreMod(O, UO);
14111     Visit(UO->getSubExpr());
14112     notePostMod(O, UO, UK_ModAsSideEffect);
14113   }
14114 
14115   void VisitBinLOr(const BinaryOperator *BO) {
14116     // C++11 [expr.log.or]p2:
14117     //  If the second expression is evaluated, every value computation and
14118     //  side effect associated with the first expression is sequenced before
14119     //  every value computation and side effect associated with the
14120     //  second expression.
14121     SequenceTree::Seq LHSRegion = Tree.allocate(Region);
14122     SequenceTree::Seq RHSRegion = Tree.allocate(Region);
14123     SequenceTree::Seq OldRegion = Region;
14124 
14125     EvaluationTracker Eval(*this);
14126     {
14127       SequencedSubexpression Sequenced(*this);
14128       Region = LHSRegion;
14129       Visit(BO->getLHS());
14130     }
14131 
14132     // C++11 [expr.log.or]p1:
14133     //  [...] the second operand is not evaluated if the first operand
14134     //  evaluates to true.
14135     bool EvalResult = false;
14136     bool EvalOK = Eval.evaluate(BO->getLHS(), EvalResult);
14137     bool ShouldVisitRHS = !EvalOK || (EvalOK && !EvalResult);
14138     if (ShouldVisitRHS) {
14139       Region = RHSRegion;
14140       Visit(BO->getRHS());
14141     }
14142 
14143     Region = OldRegion;
14144     Tree.merge(LHSRegion);
14145     Tree.merge(RHSRegion);
14146   }
14147 
14148   void VisitBinLAnd(const BinaryOperator *BO) {
14149     // C++11 [expr.log.and]p2:
14150     //  If the second expression is evaluated, every value computation and
14151     //  side effect associated with the first expression is sequenced before
14152     //  every value computation and side effect associated with the
14153     //  second expression.
14154     SequenceTree::Seq LHSRegion = Tree.allocate(Region);
14155     SequenceTree::Seq RHSRegion = Tree.allocate(Region);
14156     SequenceTree::Seq OldRegion = Region;
14157 
14158     EvaluationTracker Eval(*this);
14159     {
14160       SequencedSubexpression Sequenced(*this);
14161       Region = LHSRegion;
14162       Visit(BO->getLHS());
14163     }
14164 
14165     // C++11 [expr.log.and]p1:
14166     //  [...] the second operand is not evaluated if the first operand is false.
14167     bool EvalResult = false;
14168     bool EvalOK = Eval.evaluate(BO->getLHS(), EvalResult);
14169     bool ShouldVisitRHS = !EvalOK || (EvalOK && EvalResult);
14170     if (ShouldVisitRHS) {
14171       Region = RHSRegion;
14172       Visit(BO->getRHS());
14173     }
14174 
14175     Region = OldRegion;
14176     Tree.merge(LHSRegion);
14177     Tree.merge(RHSRegion);
14178   }
14179 
14180   void VisitAbstractConditionalOperator(const AbstractConditionalOperator *CO) {
14181     // C++11 [expr.cond]p1:
14182     //  [...] Every value computation and side effect associated with the first
14183     //  expression is sequenced before every value computation and side effect
14184     //  associated with the second or third expression.
14185     SequenceTree::Seq ConditionRegion = Tree.allocate(Region);
14186 
14187     // No sequencing is specified between the true and false expression.
14188     // However since exactly one of both is going to be evaluated we can
14189     // consider them to be sequenced. This is needed to avoid warning on
14190     // something like "x ? y+= 1 : y += 2;" in the case where we will visit
14191     // both the true and false expressions because we can't evaluate x.
14192     // This will still allow us to detect an expression like (pre C++17)
14193     // "(x ? y += 1 : y += 2) = y".
14194     //
14195     // We don't wrap the visitation of the true and false expression with
14196     // SequencedSubexpression because we don't want to downgrade modifications
14197     // as side effect in the true and false expressions after the visition
14198     // is done. (for example in the expression "(x ? y++ : y++) + y" we should
14199     // not warn between the two "y++", but we should warn between the "y++"
14200     // and the "y".
14201     SequenceTree::Seq TrueRegion = Tree.allocate(Region);
14202     SequenceTree::Seq FalseRegion = Tree.allocate(Region);
14203     SequenceTree::Seq OldRegion = Region;
14204 
14205     EvaluationTracker Eval(*this);
14206     {
14207       SequencedSubexpression Sequenced(*this);
14208       Region = ConditionRegion;
14209       Visit(CO->getCond());
14210     }
14211 
14212     // C++11 [expr.cond]p1:
14213     // [...] The first expression is contextually converted to bool (Clause 4).
14214     // It is evaluated and if it is true, the result of the conditional
14215     // expression is the value of the second expression, otherwise that of the
14216     // third expression. Only one of the second and third expressions is
14217     // evaluated. [...]
14218     bool EvalResult = false;
14219     bool EvalOK = Eval.evaluate(CO->getCond(), EvalResult);
14220     bool ShouldVisitTrueExpr = !EvalOK || (EvalOK && EvalResult);
14221     bool ShouldVisitFalseExpr = !EvalOK || (EvalOK && !EvalResult);
14222     if (ShouldVisitTrueExpr) {
14223       Region = TrueRegion;
14224       Visit(CO->getTrueExpr());
14225     }
14226     if (ShouldVisitFalseExpr) {
14227       Region = FalseRegion;
14228       Visit(CO->getFalseExpr());
14229     }
14230 
14231     Region = OldRegion;
14232     Tree.merge(ConditionRegion);
14233     Tree.merge(TrueRegion);
14234     Tree.merge(FalseRegion);
14235   }
14236 
14237   void VisitCallExpr(const CallExpr *CE) {
14238     // FIXME: CXXNewExpr and CXXDeleteExpr implicitly call functions.
14239 
14240     if (CE->isUnevaluatedBuiltinCall(Context))
14241       return;
14242 
14243     // C++11 [intro.execution]p15:
14244     //   When calling a function [...], every value computation and side effect
14245     //   associated with any argument expression, or with the postfix expression
14246     //   designating the called function, is sequenced before execution of every
14247     //   expression or statement in the body of the function [and thus before
14248     //   the value computation of its result].
14249     SequencedSubexpression Sequenced(*this);
14250     SemaRef.runWithSufficientStackSpace(CE->getExprLoc(), [&] {
14251       // C++17 [expr.call]p5
14252       //   The postfix-expression is sequenced before each expression in the
14253       //   expression-list and any default argument. [...]
14254       SequenceTree::Seq CalleeRegion;
14255       SequenceTree::Seq OtherRegion;
14256       if (SemaRef.getLangOpts().CPlusPlus17) {
14257         CalleeRegion = Tree.allocate(Region);
14258         OtherRegion = Tree.allocate(Region);
14259       } else {
14260         CalleeRegion = Region;
14261         OtherRegion = Region;
14262       }
14263       SequenceTree::Seq OldRegion = Region;
14264 
14265       // Visit the callee expression first.
14266       Region = CalleeRegion;
14267       if (SemaRef.getLangOpts().CPlusPlus17) {
14268         SequencedSubexpression Sequenced(*this);
14269         Visit(CE->getCallee());
14270       } else {
14271         Visit(CE->getCallee());
14272       }
14273 
14274       // Then visit the argument expressions.
14275       Region = OtherRegion;
14276       for (const Expr *Argument : CE->arguments())
14277         Visit(Argument);
14278 
14279       Region = OldRegion;
14280       if (SemaRef.getLangOpts().CPlusPlus17) {
14281         Tree.merge(CalleeRegion);
14282         Tree.merge(OtherRegion);
14283       }
14284     });
14285   }
14286 
14287   void VisitCXXOperatorCallExpr(const CXXOperatorCallExpr *CXXOCE) {
14288     // C++17 [over.match.oper]p2:
14289     //   [...] the operator notation is first transformed to the equivalent
14290     //   function-call notation as summarized in Table 12 (where @ denotes one
14291     //   of the operators covered in the specified subclause). However, the
14292     //   operands are sequenced in the order prescribed for the built-in
14293     //   operator (Clause 8).
14294     //
14295     // From the above only overloaded binary operators and overloaded call
14296     // operators have sequencing rules in C++17 that we need to handle
14297     // separately.
14298     if (!SemaRef.getLangOpts().CPlusPlus17 ||
14299         (CXXOCE->getNumArgs() != 2 && CXXOCE->getOperator() != OO_Call))
14300       return VisitCallExpr(CXXOCE);
14301 
14302     enum {
14303       NoSequencing,
14304       LHSBeforeRHS,
14305       RHSBeforeLHS,
14306       LHSBeforeRest
14307     } SequencingKind;
14308     switch (CXXOCE->getOperator()) {
14309     case OO_Equal:
14310     case OO_PlusEqual:
14311     case OO_MinusEqual:
14312     case OO_StarEqual:
14313     case OO_SlashEqual:
14314     case OO_PercentEqual:
14315     case OO_CaretEqual:
14316     case OO_AmpEqual:
14317     case OO_PipeEqual:
14318     case OO_LessLessEqual:
14319     case OO_GreaterGreaterEqual:
14320       SequencingKind = RHSBeforeLHS;
14321       break;
14322 
14323     case OO_LessLess:
14324     case OO_GreaterGreater:
14325     case OO_AmpAmp:
14326     case OO_PipePipe:
14327     case OO_Comma:
14328     case OO_ArrowStar:
14329     case OO_Subscript:
14330       SequencingKind = LHSBeforeRHS;
14331       break;
14332 
14333     case OO_Call:
14334       SequencingKind = LHSBeforeRest;
14335       break;
14336 
14337     default:
14338       SequencingKind = NoSequencing;
14339       break;
14340     }
14341 
14342     if (SequencingKind == NoSequencing)
14343       return VisitCallExpr(CXXOCE);
14344 
14345     // This is a call, so all subexpressions are sequenced before the result.
14346     SequencedSubexpression Sequenced(*this);
14347 
14348     SemaRef.runWithSufficientStackSpace(CXXOCE->getExprLoc(), [&] {
14349       assert(SemaRef.getLangOpts().CPlusPlus17 &&
14350              "Should only get there with C++17 and above!");
14351       assert((CXXOCE->getNumArgs() == 2 || CXXOCE->getOperator() == OO_Call) &&
14352              "Should only get there with an overloaded binary operator"
14353              " or an overloaded call operator!");
14354 
14355       if (SequencingKind == LHSBeforeRest) {
14356         assert(CXXOCE->getOperator() == OO_Call &&
14357                "We should only have an overloaded call operator here!");
14358 
14359         // This is very similar to VisitCallExpr, except that we only have the
14360         // C++17 case. The postfix-expression is the first argument of the
14361         // CXXOperatorCallExpr. The expressions in the expression-list, if any,
14362         // are in the following arguments.
14363         //
14364         // Note that we intentionally do not visit the callee expression since
14365         // it is just a decayed reference to a function.
14366         SequenceTree::Seq PostfixExprRegion = Tree.allocate(Region);
14367         SequenceTree::Seq ArgsRegion = Tree.allocate(Region);
14368         SequenceTree::Seq OldRegion = Region;
14369 
14370         assert(CXXOCE->getNumArgs() >= 1 &&
14371                "An overloaded call operator must have at least one argument"
14372                " for the postfix-expression!");
14373         const Expr *PostfixExpr = CXXOCE->getArgs()[0];
14374         llvm::ArrayRef<const Expr *> Args(CXXOCE->getArgs() + 1,
14375                                           CXXOCE->getNumArgs() - 1);
14376 
14377         // Visit the postfix-expression first.
14378         {
14379           Region = PostfixExprRegion;
14380           SequencedSubexpression Sequenced(*this);
14381           Visit(PostfixExpr);
14382         }
14383 
14384         // Then visit the argument expressions.
14385         Region = ArgsRegion;
14386         for (const Expr *Arg : Args)
14387           Visit(Arg);
14388 
14389         Region = OldRegion;
14390         Tree.merge(PostfixExprRegion);
14391         Tree.merge(ArgsRegion);
14392       } else {
14393         assert(CXXOCE->getNumArgs() == 2 &&
14394                "Should only have two arguments here!");
14395         assert((SequencingKind == LHSBeforeRHS ||
14396                 SequencingKind == RHSBeforeLHS) &&
14397                "Unexpected sequencing kind!");
14398 
14399         // We do not visit the callee expression since it is just a decayed
14400         // reference to a function.
14401         const Expr *E1 = CXXOCE->getArg(0);
14402         const Expr *E2 = CXXOCE->getArg(1);
14403         if (SequencingKind == RHSBeforeLHS)
14404           std::swap(E1, E2);
14405 
14406         return VisitSequencedExpressions(E1, E2);
14407       }
14408     });
14409   }
14410 
14411   void VisitCXXConstructExpr(const CXXConstructExpr *CCE) {
14412     // This is a call, so all subexpressions are sequenced before the result.
14413     SequencedSubexpression Sequenced(*this);
14414 
14415     if (!CCE->isListInitialization())
14416       return VisitExpr(CCE);
14417 
14418     // In C++11, list initializations are sequenced.
14419     SmallVector<SequenceTree::Seq, 32> Elts;
14420     SequenceTree::Seq Parent = Region;
14421     for (CXXConstructExpr::const_arg_iterator I = CCE->arg_begin(),
14422                                               E = CCE->arg_end();
14423          I != E; ++I) {
14424       Region = Tree.allocate(Parent);
14425       Elts.push_back(Region);
14426       Visit(*I);
14427     }
14428 
14429     // Forget that the initializers are sequenced.
14430     Region = Parent;
14431     for (unsigned I = 0; I < Elts.size(); ++I)
14432       Tree.merge(Elts[I]);
14433   }
14434 
14435   void VisitInitListExpr(const InitListExpr *ILE) {
14436     if (!SemaRef.getLangOpts().CPlusPlus11)
14437       return VisitExpr(ILE);
14438 
14439     // In C++11, list initializations are sequenced.
14440     SmallVector<SequenceTree::Seq, 32> Elts;
14441     SequenceTree::Seq Parent = Region;
14442     for (unsigned I = 0; I < ILE->getNumInits(); ++I) {
14443       const Expr *E = ILE->getInit(I);
14444       if (!E)
14445         continue;
14446       Region = Tree.allocate(Parent);
14447       Elts.push_back(Region);
14448       Visit(E);
14449     }
14450 
14451     // Forget that the initializers are sequenced.
14452     Region = Parent;
14453     for (unsigned I = 0; I < Elts.size(); ++I)
14454       Tree.merge(Elts[I]);
14455   }
14456 };
14457 
14458 } // namespace
14459 
14460 void Sema::CheckUnsequencedOperations(const Expr *E) {
14461   SmallVector<const Expr *, 8> WorkList;
14462   WorkList.push_back(E);
14463   while (!WorkList.empty()) {
14464     const Expr *Item = WorkList.pop_back_val();
14465     SequenceChecker(*this, Item, WorkList);
14466   }
14467 }
14468 
14469 void Sema::CheckCompletedExpr(Expr *E, SourceLocation CheckLoc,
14470                               bool IsConstexpr) {
14471   llvm::SaveAndRestore<bool> ConstantContext(
14472       isConstantEvaluatedOverride, IsConstexpr || isa<ConstantExpr>(E));
14473   CheckImplicitConversions(E, CheckLoc);
14474   if (!E->isInstantiationDependent())
14475     CheckUnsequencedOperations(E);
14476   if (!IsConstexpr && !E->isValueDependent())
14477     CheckForIntOverflow(E);
14478   DiagnoseMisalignedMembers();
14479 }
14480 
14481 void Sema::CheckBitFieldInitialization(SourceLocation InitLoc,
14482                                        FieldDecl *BitField,
14483                                        Expr *Init) {
14484   (void) AnalyzeBitFieldAssignment(*this, BitField, Init, InitLoc);
14485 }
14486 
14487 static void diagnoseArrayStarInParamType(Sema &S, QualType PType,
14488                                          SourceLocation Loc) {
14489   if (!PType->isVariablyModifiedType())
14490     return;
14491   if (const auto *PointerTy = dyn_cast<PointerType>(PType)) {
14492     diagnoseArrayStarInParamType(S, PointerTy->getPointeeType(), Loc);
14493     return;
14494   }
14495   if (const auto *ReferenceTy = dyn_cast<ReferenceType>(PType)) {
14496     diagnoseArrayStarInParamType(S, ReferenceTy->getPointeeType(), Loc);
14497     return;
14498   }
14499   if (const auto *ParenTy = dyn_cast<ParenType>(PType)) {
14500     diagnoseArrayStarInParamType(S, ParenTy->getInnerType(), Loc);
14501     return;
14502   }
14503 
14504   const ArrayType *AT = S.Context.getAsArrayType(PType);
14505   if (!AT)
14506     return;
14507 
14508   if (AT->getSizeModifier() != ArrayType::Star) {
14509     diagnoseArrayStarInParamType(S, AT->getElementType(), Loc);
14510     return;
14511   }
14512 
14513   S.Diag(Loc, diag::err_array_star_in_function_definition);
14514 }
14515 
14516 /// CheckParmsForFunctionDef - Check that the parameters of the given
14517 /// function are appropriate for the definition of a function. This
14518 /// takes care of any checks that cannot be performed on the
14519 /// declaration itself, e.g., that the types of each of the function
14520 /// parameters are complete.
14521 bool Sema::CheckParmsForFunctionDef(ArrayRef<ParmVarDecl *> Parameters,
14522                                     bool CheckParameterNames) {
14523   bool HasInvalidParm = false;
14524   for (ParmVarDecl *Param : Parameters) {
14525     // C99 6.7.5.3p4: the parameters in a parameter type list in a
14526     // function declarator that is part of a function definition of
14527     // that function shall not have incomplete type.
14528     //
14529     // This is also C++ [dcl.fct]p6.
14530     if (!Param->isInvalidDecl() &&
14531         RequireCompleteType(Param->getLocation(), Param->getType(),
14532                             diag::err_typecheck_decl_incomplete_type)) {
14533       Param->setInvalidDecl();
14534       HasInvalidParm = true;
14535     }
14536 
14537     // C99 6.9.1p5: If the declarator includes a parameter type list, the
14538     // declaration of each parameter shall include an identifier.
14539     if (CheckParameterNames && Param->getIdentifier() == nullptr &&
14540         !Param->isImplicit() && !getLangOpts().CPlusPlus) {
14541       // Diagnose this as an extension in C17 and earlier.
14542       if (!getLangOpts().C2x)
14543         Diag(Param->getLocation(), diag::ext_parameter_name_omitted_c2x);
14544     }
14545 
14546     // C99 6.7.5.3p12:
14547     //   If the function declarator is not part of a definition of that
14548     //   function, parameters may have incomplete type and may use the [*]
14549     //   notation in their sequences of declarator specifiers to specify
14550     //   variable length array types.
14551     QualType PType = Param->getOriginalType();
14552     // FIXME: This diagnostic should point the '[*]' if source-location
14553     // information is added for it.
14554     diagnoseArrayStarInParamType(*this, PType, Param->getLocation());
14555 
14556     // If the parameter is a c++ class type and it has to be destructed in the
14557     // callee function, declare the destructor so that it can be called by the
14558     // callee function. Do not perform any direct access check on the dtor here.
14559     if (!Param->isInvalidDecl()) {
14560       if (CXXRecordDecl *ClassDecl = Param->getType()->getAsCXXRecordDecl()) {
14561         if (!ClassDecl->isInvalidDecl() &&
14562             !ClassDecl->hasIrrelevantDestructor() &&
14563             !ClassDecl->isDependentContext() &&
14564             ClassDecl->isParamDestroyedInCallee()) {
14565           CXXDestructorDecl *Destructor = LookupDestructor(ClassDecl);
14566           MarkFunctionReferenced(Param->getLocation(), Destructor);
14567           DiagnoseUseOfDecl(Destructor, Param->getLocation());
14568         }
14569       }
14570     }
14571 
14572     // Parameters with the pass_object_size attribute only need to be marked
14573     // constant at function definitions. Because we lack information about
14574     // whether we're on a declaration or definition when we're instantiating the
14575     // attribute, we need to check for constness here.
14576     if (const auto *Attr = Param->getAttr<PassObjectSizeAttr>())
14577       if (!Param->getType().isConstQualified())
14578         Diag(Param->getLocation(), diag::err_attribute_pointers_only)
14579             << Attr->getSpelling() << 1;
14580 
14581     // Check for parameter names shadowing fields from the class.
14582     if (LangOpts.CPlusPlus && !Param->isInvalidDecl()) {
14583       // The owning context for the parameter should be the function, but we
14584       // want to see if this function's declaration context is a record.
14585       DeclContext *DC = Param->getDeclContext();
14586       if (DC && DC->isFunctionOrMethod()) {
14587         if (auto *RD = dyn_cast<CXXRecordDecl>(DC->getParent()))
14588           CheckShadowInheritedFields(Param->getLocation(), Param->getDeclName(),
14589                                      RD, /*DeclIsField*/ false);
14590       }
14591     }
14592   }
14593 
14594   return HasInvalidParm;
14595 }
14596 
14597 Optional<std::pair<CharUnits, CharUnits>>
14598 static getBaseAlignmentAndOffsetFromPtr(const Expr *E, ASTContext &Ctx);
14599 
14600 /// Compute the alignment and offset of the base class object given the
14601 /// derived-to-base cast expression and the alignment and offset of the derived
14602 /// class object.
14603 static std::pair<CharUnits, CharUnits>
14604 getDerivedToBaseAlignmentAndOffset(const CastExpr *CE, QualType DerivedType,
14605                                    CharUnits BaseAlignment, CharUnits Offset,
14606                                    ASTContext &Ctx) {
14607   for (auto PathI = CE->path_begin(), PathE = CE->path_end(); PathI != PathE;
14608        ++PathI) {
14609     const CXXBaseSpecifier *Base = *PathI;
14610     const CXXRecordDecl *BaseDecl = Base->getType()->getAsCXXRecordDecl();
14611     if (Base->isVirtual()) {
14612       // The complete object may have a lower alignment than the non-virtual
14613       // alignment of the base, in which case the base may be misaligned. Choose
14614       // the smaller of the non-virtual alignment and BaseAlignment, which is a
14615       // conservative lower bound of the complete object alignment.
14616       CharUnits NonVirtualAlignment =
14617           Ctx.getASTRecordLayout(BaseDecl).getNonVirtualAlignment();
14618       BaseAlignment = std::min(BaseAlignment, NonVirtualAlignment);
14619       Offset = CharUnits::Zero();
14620     } else {
14621       const ASTRecordLayout &RL =
14622           Ctx.getASTRecordLayout(DerivedType->getAsCXXRecordDecl());
14623       Offset += RL.getBaseClassOffset(BaseDecl);
14624     }
14625     DerivedType = Base->getType();
14626   }
14627 
14628   return std::make_pair(BaseAlignment, Offset);
14629 }
14630 
14631 /// Compute the alignment and offset of a binary additive operator.
14632 static Optional<std::pair<CharUnits, CharUnits>>
14633 getAlignmentAndOffsetFromBinAddOrSub(const Expr *PtrE, const Expr *IntE,
14634                                      bool IsSub, ASTContext &Ctx) {
14635   QualType PointeeType = PtrE->getType()->getPointeeType();
14636 
14637   if (!PointeeType->isConstantSizeType())
14638     return llvm::None;
14639 
14640   auto P = getBaseAlignmentAndOffsetFromPtr(PtrE, Ctx);
14641 
14642   if (!P)
14643     return llvm::None;
14644 
14645   CharUnits EltSize = Ctx.getTypeSizeInChars(PointeeType);
14646   if (Optional<llvm::APSInt> IdxRes = IntE->getIntegerConstantExpr(Ctx)) {
14647     CharUnits Offset = EltSize * IdxRes->getExtValue();
14648     if (IsSub)
14649       Offset = -Offset;
14650     return std::make_pair(P->first, P->second + Offset);
14651   }
14652 
14653   // If the integer expression isn't a constant expression, compute the lower
14654   // bound of the alignment using the alignment and offset of the pointer
14655   // expression and the element size.
14656   return std::make_pair(
14657       P->first.alignmentAtOffset(P->second).alignmentAtOffset(EltSize),
14658       CharUnits::Zero());
14659 }
14660 
14661 /// This helper function takes an lvalue expression and returns the alignment of
14662 /// a VarDecl and a constant offset from the VarDecl.
14663 Optional<std::pair<CharUnits, CharUnits>>
14664 static getBaseAlignmentAndOffsetFromLValue(const Expr *E, ASTContext &Ctx) {
14665   E = E->IgnoreParens();
14666   switch (E->getStmtClass()) {
14667   default:
14668     break;
14669   case Stmt::CStyleCastExprClass:
14670   case Stmt::CXXStaticCastExprClass:
14671   case Stmt::ImplicitCastExprClass: {
14672     auto *CE = cast<CastExpr>(E);
14673     const Expr *From = CE->getSubExpr();
14674     switch (CE->getCastKind()) {
14675     default:
14676       break;
14677     case CK_NoOp:
14678       return getBaseAlignmentAndOffsetFromLValue(From, Ctx);
14679     case CK_UncheckedDerivedToBase:
14680     case CK_DerivedToBase: {
14681       auto P = getBaseAlignmentAndOffsetFromLValue(From, Ctx);
14682       if (!P)
14683         break;
14684       return getDerivedToBaseAlignmentAndOffset(CE, From->getType(), P->first,
14685                                                 P->second, Ctx);
14686     }
14687     }
14688     break;
14689   }
14690   case Stmt::ArraySubscriptExprClass: {
14691     auto *ASE = cast<ArraySubscriptExpr>(E);
14692     return getAlignmentAndOffsetFromBinAddOrSub(ASE->getBase(), ASE->getIdx(),
14693                                                 false, Ctx);
14694   }
14695   case Stmt::DeclRefExprClass: {
14696     if (auto *VD = dyn_cast<VarDecl>(cast<DeclRefExpr>(E)->getDecl())) {
14697       // FIXME: If VD is captured by copy or is an escaping __block variable,
14698       // use the alignment of VD's type.
14699       if (!VD->getType()->isReferenceType())
14700         return std::make_pair(Ctx.getDeclAlign(VD), CharUnits::Zero());
14701       if (VD->hasInit())
14702         return getBaseAlignmentAndOffsetFromLValue(VD->getInit(), Ctx);
14703     }
14704     break;
14705   }
14706   case Stmt::MemberExprClass: {
14707     auto *ME = cast<MemberExpr>(E);
14708     auto *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
14709     if (!FD || FD->getType()->isReferenceType() ||
14710         FD->getParent()->isInvalidDecl())
14711       break;
14712     Optional<std::pair<CharUnits, CharUnits>> P;
14713     if (ME->isArrow())
14714       P = getBaseAlignmentAndOffsetFromPtr(ME->getBase(), Ctx);
14715     else
14716       P = getBaseAlignmentAndOffsetFromLValue(ME->getBase(), Ctx);
14717     if (!P)
14718       break;
14719     const ASTRecordLayout &Layout = Ctx.getASTRecordLayout(FD->getParent());
14720     uint64_t Offset = Layout.getFieldOffset(FD->getFieldIndex());
14721     return std::make_pair(P->first,
14722                           P->second + CharUnits::fromQuantity(Offset));
14723   }
14724   case Stmt::UnaryOperatorClass: {
14725     auto *UO = cast<UnaryOperator>(E);
14726     switch (UO->getOpcode()) {
14727     default:
14728       break;
14729     case UO_Deref:
14730       return getBaseAlignmentAndOffsetFromPtr(UO->getSubExpr(), Ctx);
14731     }
14732     break;
14733   }
14734   case Stmt::BinaryOperatorClass: {
14735     auto *BO = cast<BinaryOperator>(E);
14736     auto Opcode = BO->getOpcode();
14737     switch (Opcode) {
14738     default:
14739       break;
14740     case BO_Comma:
14741       return getBaseAlignmentAndOffsetFromLValue(BO->getRHS(), Ctx);
14742     }
14743     break;
14744   }
14745   }
14746   return llvm::None;
14747 }
14748 
14749 /// This helper function takes a pointer expression and returns the alignment of
14750 /// a VarDecl and a constant offset from the VarDecl.
14751 Optional<std::pair<CharUnits, CharUnits>>
14752 static getBaseAlignmentAndOffsetFromPtr(const Expr *E, ASTContext &Ctx) {
14753   E = E->IgnoreParens();
14754   switch (E->getStmtClass()) {
14755   default:
14756     break;
14757   case Stmt::CStyleCastExprClass:
14758   case Stmt::CXXStaticCastExprClass:
14759   case Stmt::ImplicitCastExprClass: {
14760     auto *CE = cast<CastExpr>(E);
14761     const Expr *From = CE->getSubExpr();
14762     switch (CE->getCastKind()) {
14763     default:
14764       break;
14765     case CK_NoOp:
14766       return getBaseAlignmentAndOffsetFromPtr(From, Ctx);
14767     case CK_ArrayToPointerDecay:
14768       return getBaseAlignmentAndOffsetFromLValue(From, Ctx);
14769     case CK_UncheckedDerivedToBase:
14770     case CK_DerivedToBase: {
14771       auto P = getBaseAlignmentAndOffsetFromPtr(From, Ctx);
14772       if (!P)
14773         break;
14774       return getDerivedToBaseAlignmentAndOffset(
14775           CE, From->getType()->getPointeeType(), P->first, P->second, Ctx);
14776     }
14777     }
14778     break;
14779   }
14780   case Stmt::CXXThisExprClass: {
14781     auto *RD = E->getType()->getPointeeType()->getAsCXXRecordDecl();
14782     CharUnits Alignment = Ctx.getASTRecordLayout(RD).getNonVirtualAlignment();
14783     return std::make_pair(Alignment, CharUnits::Zero());
14784   }
14785   case Stmt::UnaryOperatorClass: {
14786     auto *UO = cast<UnaryOperator>(E);
14787     if (UO->getOpcode() == UO_AddrOf)
14788       return getBaseAlignmentAndOffsetFromLValue(UO->getSubExpr(), Ctx);
14789     break;
14790   }
14791   case Stmt::BinaryOperatorClass: {
14792     auto *BO = cast<BinaryOperator>(E);
14793     auto Opcode = BO->getOpcode();
14794     switch (Opcode) {
14795     default:
14796       break;
14797     case BO_Add:
14798     case BO_Sub: {
14799       const Expr *LHS = BO->getLHS(), *RHS = BO->getRHS();
14800       if (Opcode == BO_Add && !RHS->getType()->isIntegralOrEnumerationType())
14801         std::swap(LHS, RHS);
14802       return getAlignmentAndOffsetFromBinAddOrSub(LHS, RHS, Opcode == BO_Sub,
14803                                                   Ctx);
14804     }
14805     case BO_Comma:
14806       return getBaseAlignmentAndOffsetFromPtr(BO->getRHS(), Ctx);
14807     }
14808     break;
14809   }
14810   }
14811   return llvm::None;
14812 }
14813 
14814 static CharUnits getPresumedAlignmentOfPointer(const Expr *E, Sema &S) {
14815   // See if we can compute the alignment of a VarDecl and an offset from it.
14816   Optional<std::pair<CharUnits, CharUnits>> P =
14817       getBaseAlignmentAndOffsetFromPtr(E, S.Context);
14818 
14819   if (P)
14820     return P->first.alignmentAtOffset(P->second);
14821 
14822   // If that failed, return the type's alignment.
14823   return S.Context.getTypeAlignInChars(E->getType()->getPointeeType());
14824 }
14825 
14826 /// CheckCastAlign - Implements -Wcast-align, which warns when a
14827 /// pointer cast increases the alignment requirements.
14828 void Sema::CheckCastAlign(Expr *Op, QualType T, SourceRange TRange) {
14829   // This is actually a lot of work to potentially be doing on every
14830   // cast; don't do it if we're ignoring -Wcast_align (as is the default).
14831   if (getDiagnostics().isIgnored(diag::warn_cast_align, TRange.getBegin()))
14832     return;
14833 
14834   // Ignore dependent types.
14835   if (T->isDependentType() || Op->getType()->isDependentType())
14836     return;
14837 
14838   // Require that the destination be a pointer type.
14839   const PointerType *DestPtr = T->getAs<PointerType>();
14840   if (!DestPtr) return;
14841 
14842   // If the destination has alignment 1, we're done.
14843   QualType DestPointee = DestPtr->getPointeeType();
14844   if (DestPointee->isIncompleteType()) return;
14845   CharUnits DestAlign = Context.getTypeAlignInChars(DestPointee);
14846   if (DestAlign.isOne()) return;
14847 
14848   // Require that the source be a pointer type.
14849   const PointerType *SrcPtr = Op->getType()->getAs<PointerType>();
14850   if (!SrcPtr) return;
14851   QualType SrcPointee = SrcPtr->getPointeeType();
14852 
14853   // Explicitly allow casts from cv void*.  We already implicitly
14854   // allowed casts to cv void*, since they have alignment 1.
14855   // Also allow casts involving incomplete types, which implicitly
14856   // includes 'void'.
14857   if (SrcPointee->isIncompleteType()) return;
14858 
14859   CharUnits SrcAlign = getPresumedAlignmentOfPointer(Op, *this);
14860 
14861   if (SrcAlign >= DestAlign) return;
14862 
14863   Diag(TRange.getBegin(), diag::warn_cast_align)
14864     << Op->getType() << T
14865     << static_cast<unsigned>(SrcAlign.getQuantity())
14866     << static_cast<unsigned>(DestAlign.getQuantity())
14867     << TRange << Op->getSourceRange();
14868 }
14869 
14870 /// Check whether this array fits the idiom of a size-one tail padded
14871 /// array member of a struct.
14872 ///
14873 /// We avoid emitting out-of-bounds access warnings for such arrays as they are
14874 /// commonly used to emulate flexible arrays in C89 code.
14875 static bool IsTailPaddedMemberArray(Sema &S, const llvm::APInt &Size,
14876                                     const NamedDecl *ND) {
14877   if (Size != 1 || !ND) return false;
14878 
14879   const FieldDecl *FD = dyn_cast<FieldDecl>(ND);
14880   if (!FD) return false;
14881 
14882   // Don't consider sizes resulting from macro expansions or template argument
14883   // substitution to form C89 tail-padded arrays.
14884 
14885   TypeSourceInfo *TInfo = FD->getTypeSourceInfo();
14886   while (TInfo) {
14887     TypeLoc TL = TInfo->getTypeLoc();
14888     // Look through typedefs.
14889     if (TypedefTypeLoc TTL = TL.getAs<TypedefTypeLoc>()) {
14890       const TypedefNameDecl *TDL = TTL.getTypedefNameDecl();
14891       TInfo = TDL->getTypeSourceInfo();
14892       continue;
14893     }
14894     if (ConstantArrayTypeLoc CTL = TL.getAs<ConstantArrayTypeLoc>()) {
14895       const Expr *SizeExpr = dyn_cast<IntegerLiteral>(CTL.getSizeExpr());
14896       if (!SizeExpr || SizeExpr->getExprLoc().isMacroID())
14897         return false;
14898     }
14899     break;
14900   }
14901 
14902   const RecordDecl *RD = dyn_cast<RecordDecl>(FD->getDeclContext());
14903   if (!RD) return false;
14904   if (RD->isUnion()) return false;
14905   if (const CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) {
14906     if (!CRD->isStandardLayout()) return false;
14907   }
14908 
14909   // See if this is the last field decl in the record.
14910   const Decl *D = FD;
14911   while ((D = D->getNextDeclInContext()))
14912     if (isa<FieldDecl>(D))
14913       return false;
14914   return true;
14915 }
14916 
14917 void Sema::CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
14918                             const ArraySubscriptExpr *ASE,
14919                             bool AllowOnePastEnd, bool IndexNegated) {
14920   // Already diagnosed by the constant evaluator.
14921   if (isConstantEvaluated())
14922     return;
14923 
14924   IndexExpr = IndexExpr->IgnoreParenImpCasts();
14925   if (IndexExpr->isValueDependent())
14926     return;
14927 
14928   const Type *EffectiveType =
14929       BaseExpr->getType()->getPointeeOrArrayElementType();
14930   BaseExpr = BaseExpr->IgnoreParenCasts();
14931   const ConstantArrayType *ArrayTy =
14932       Context.getAsConstantArrayType(BaseExpr->getType());
14933 
14934   const Type *BaseType =
14935       ArrayTy == nullptr ? nullptr : ArrayTy->getElementType().getTypePtr();
14936   bool IsUnboundedArray = (BaseType == nullptr);
14937   if (EffectiveType->isDependentType() ||
14938       (!IsUnboundedArray && BaseType->isDependentType()))
14939     return;
14940 
14941   Expr::EvalResult Result;
14942   if (!IndexExpr->EvaluateAsInt(Result, Context, Expr::SE_AllowSideEffects))
14943     return;
14944 
14945   llvm::APSInt index = Result.Val.getInt();
14946   if (IndexNegated) {
14947     index.setIsUnsigned(false);
14948     index = -index;
14949   }
14950 
14951   const NamedDecl *ND = nullptr;
14952   if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(BaseExpr))
14953     ND = DRE->getDecl();
14954   if (const MemberExpr *ME = dyn_cast<MemberExpr>(BaseExpr))
14955     ND = ME->getMemberDecl();
14956 
14957   if (IsUnboundedArray) {
14958     if (index.isUnsigned() || !index.isNegative()) {
14959       const auto &ASTC = getASTContext();
14960       unsigned AddrBits =
14961           ASTC.getTargetInfo().getPointerWidth(ASTC.getTargetAddressSpace(
14962               EffectiveType->getCanonicalTypeInternal()));
14963       if (index.getBitWidth() < AddrBits)
14964         index = index.zext(AddrBits);
14965       Optional<CharUnits> ElemCharUnits =
14966           ASTC.getTypeSizeInCharsIfKnown(EffectiveType);
14967       // PR50741 - If EffectiveType has unknown size (e.g., if it's a void
14968       // pointer) bounds-checking isn't meaningful.
14969       if (!ElemCharUnits)
14970         return;
14971       llvm::APInt ElemBytes(index.getBitWidth(), ElemCharUnits->getQuantity());
14972       // If index has more active bits than address space, we already know
14973       // we have a bounds violation to warn about.  Otherwise, compute
14974       // address of (index + 1)th element, and warn about bounds violation
14975       // only if that address exceeds address space.
14976       if (index.getActiveBits() <= AddrBits) {
14977         bool Overflow;
14978         llvm::APInt Product(index);
14979         Product += 1;
14980         Product = Product.umul_ov(ElemBytes, Overflow);
14981         if (!Overflow && Product.getActiveBits() <= AddrBits)
14982           return;
14983       }
14984 
14985       // Need to compute max possible elements in address space, since that
14986       // is included in diag message.
14987       llvm::APInt MaxElems = llvm::APInt::getMaxValue(AddrBits);
14988       MaxElems = MaxElems.zext(std::max(AddrBits + 1, ElemBytes.getBitWidth()));
14989       MaxElems += 1;
14990       ElemBytes = ElemBytes.zextOrTrunc(MaxElems.getBitWidth());
14991       MaxElems = MaxElems.udiv(ElemBytes);
14992 
14993       unsigned DiagID =
14994           ASE ? diag::warn_array_index_exceeds_max_addressable_bounds
14995               : diag::warn_ptr_arith_exceeds_max_addressable_bounds;
14996 
14997       // Diag message shows element size in bits and in "bytes" (platform-
14998       // dependent CharUnits)
14999       DiagRuntimeBehavior(BaseExpr->getBeginLoc(), BaseExpr,
15000                           PDiag(DiagID)
15001                               << toString(index, 10, true) << AddrBits
15002                               << (unsigned)ASTC.toBits(*ElemCharUnits)
15003                               << toString(ElemBytes, 10, false)
15004                               << toString(MaxElems, 10, false)
15005                               << (unsigned)MaxElems.getLimitedValue(~0U)
15006                               << IndexExpr->getSourceRange());
15007 
15008       if (!ND) {
15009         // Try harder to find a NamedDecl to point at in the note.
15010         while (const auto *ASE = dyn_cast<ArraySubscriptExpr>(BaseExpr))
15011           BaseExpr = ASE->getBase()->IgnoreParenCasts();
15012         if (const auto *DRE = dyn_cast<DeclRefExpr>(BaseExpr))
15013           ND = DRE->getDecl();
15014         if (const auto *ME = dyn_cast<MemberExpr>(BaseExpr))
15015           ND = ME->getMemberDecl();
15016       }
15017 
15018       if (ND)
15019         DiagRuntimeBehavior(ND->getBeginLoc(), BaseExpr,
15020                             PDiag(diag::note_array_declared_here) << ND);
15021     }
15022     return;
15023   }
15024 
15025   if (index.isUnsigned() || !index.isNegative()) {
15026     // It is possible that the type of the base expression after
15027     // IgnoreParenCasts is incomplete, even though the type of the base
15028     // expression before IgnoreParenCasts is complete (see PR39746 for an
15029     // example). In this case we have no information about whether the array
15030     // access exceeds the array bounds. However we can still diagnose an array
15031     // access which precedes the array bounds.
15032     if (BaseType->isIncompleteType())
15033       return;
15034 
15035     llvm::APInt size = ArrayTy->getSize();
15036     if (!size.isStrictlyPositive())
15037       return;
15038 
15039     if (BaseType != EffectiveType) {
15040       // Make sure we're comparing apples to apples when comparing index to size
15041       uint64_t ptrarith_typesize = Context.getTypeSize(EffectiveType);
15042       uint64_t array_typesize = Context.getTypeSize(BaseType);
15043       // Handle ptrarith_typesize being zero, such as when casting to void*
15044       if (!ptrarith_typesize) ptrarith_typesize = 1;
15045       if (ptrarith_typesize != array_typesize) {
15046         // There's a cast to a different size type involved
15047         uint64_t ratio = array_typesize / ptrarith_typesize;
15048         // TODO: Be smarter about handling cases where array_typesize is not a
15049         // multiple of ptrarith_typesize
15050         if (ptrarith_typesize * ratio == array_typesize)
15051           size *= llvm::APInt(size.getBitWidth(), ratio);
15052       }
15053     }
15054 
15055     if (size.getBitWidth() > index.getBitWidth())
15056       index = index.zext(size.getBitWidth());
15057     else if (size.getBitWidth() < index.getBitWidth())
15058       size = size.zext(index.getBitWidth());
15059 
15060     // For array subscripting the index must be less than size, but for pointer
15061     // arithmetic also allow the index (offset) to be equal to size since
15062     // computing the next address after the end of the array is legal and
15063     // commonly done e.g. in C++ iterators and range-based for loops.
15064     if (AllowOnePastEnd ? index.ule(size) : index.ult(size))
15065       return;
15066 
15067     // Also don't warn for arrays of size 1 which are members of some
15068     // structure. These are often used to approximate flexible arrays in C89
15069     // code.
15070     if (IsTailPaddedMemberArray(*this, size, ND))
15071       return;
15072 
15073     // Suppress the warning if the subscript expression (as identified by the
15074     // ']' location) and the index expression are both from macro expansions
15075     // within a system header.
15076     if (ASE) {
15077       SourceLocation RBracketLoc = SourceMgr.getSpellingLoc(
15078           ASE->getRBracketLoc());
15079       if (SourceMgr.isInSystemHeader(RBracketLoc)) {
15080         SourceLocation IndexLoc =
15081             SourceMgr.getSpellingLoc(IndexExpr->getBeginLoc());
15082         if (SourceMgr.isWrittenInSameFile(RBracketLoc, IndexLoc))
15083           return;
15084       }
15085     }
15086 
15087     unsigned DiagID = ASE ? diag::warn_array_index_exceeds_bounds
15088                           : diag::warn_ptr_arith_exceeds_bounds;
15089 
15090     DiagRuntimeBehavior(BaseExpr->getBeginLoc(), BaseExpr,
15091                         PDiag(DiagID) << toString(index, 10, true)
15092                                       << toString(size, 10, true)
15093                                       << (unsigned)size.getLimitedValue(~0U)
15094                                       << IndexExpr->getSourceRange());
15095   } else {
15096     unsigned DiagID = diag::warn_array_index_precedes_bounds;
15097     if (!ASE) {
15098       DiagID = diag::warn_ptr_arith_precedes_bounds;
15099       if (index.isNegative()) index = -index;
15100     }
15101 
15102     DiagRuntimeBehavior(BaseExpr->getBeginLoc(), BaseExpr,
15103                         PDiag(DiagID) << toString(index, 10, true)
15104                                       << IndexExpr->getSourceRange());
15105   }
15106 
15107   if (!ND) {
15108     // Try harder to find a NamedDecl to point at in the note.
15109     while (const auto *ASE = dyn_cast<ArraySubscriptExpr>(BaseExpr))
15110       BaseExpr = ASE->getBase()->IgnoreParenCasts();
15111     if (const auto *DRE = dyn_cast<DeclRefExpr>(BaseExpr))
15112       ND = DRE->getDecl();
15113     if (const auto *ME = dyn_cast<MemberExpr>(BaseExpr))
15114       ND = ME->getMemberDecl();
15115   }
15116 
15117   if (ND)
15118     DiagRuntimeBehavior(ND->getBeginLoc(), BaseExpr,
15119                         PDiag(diag::note_array_declared_here) << ND);
15120 }
15121 
15122 void Sema::CheckArrayAccess(const Expr *expr) {
15123   int AllowOnePastEnd = 0;
15124   while (expr) {
15125     expr = expr->IgnoreParenImpCasts();
15126     switch (expr->getStmtClass()) {
15127       case Stmt::ArraySubscriptExprClass: {
15128         const ArraySubscriptExpr *ASE = cast<ArraySubscriptExpr>(expr);
15129         CheckArrayAccess(ASE->getBase(), ASE->getIdx(), ASE,
15130                          AllowOnePastEnd > 0);
15131         expr = ASE->getBase();
15132         break;
15133       }
15134       case Stmt::MemberExprClass: {
15135         expr = cast<MemberExpr>(expr)->getBase();
15136         break;
15137       }
15138       case Stmt::OMPArraySectionExprClass: {
15139         const OMPArraySectionExpr *ASE = cast<OMPArraySectionExpr>(expr);
15140         if (ASE->getLowerBound())
15141           CheckArrayAccess(ASE->getBase(), ASE->getLowerBound(),
15142                            /*ASE=*/nullptr, AllowOnePastEnd > 0);
15143         return;
15144       }
15145       case Stmt::UnaryOperatorClass: {
15146         // Only unwrap the * and & unary operators
15147         const UnaryOperator *UO = cast<UnaryOperator>(expr);
15148         expr = UO->getSubExpr();
15149         switch (UO->getOpcode()) {
15150           case UO_AddrOf:
15151             AllowOnePastEnd++;
15152             break;
15153           case UO_Deref:
15154             AllowOnePastEnd--;
15155             break;
15156           default:
15157             return;
15158         }
15159         break;
15160       }
15161       case Stmt::ConditionalOperatorClass: {
15162         const ConditionalOperator *cond = cast<ConditionalOperator>(expr);
15163         if (const Expr *lhs = cond->getLHS())
15164           CheckArrayAccess(lhs);
15165         if (const Expr *rhs = cond->getRHS())
15166           CheckArrayAccess(rhs);
15167         return;
15168       }
15169       case Stmt::CXXOperatorCallExprClass: {
15170         const auto *OCE = cast<CXXOperatorCallExpr>(expr);
15171         for (const auto *Arg : OCE->arguments())
15172           CheckArrayAccess(Arg);
15173         return;
15174       }
15175       default:
15176         return;
15177     }
15178   }
15179 }
15180 
15181 //===--- CHECK: Objective-C retain cycles ----------------------------------//
15182 
15183 namespace {
15184 
15185 struct RetainCycleOwner {
15186   VarDecl *Variable = nullptr;
15187   SourceRange Range;
15188   SourceLocation Loc;
15189   bool Indirect = false;
15190 
15191   RetainCycleOwner() = default;
15192 
15193   void setLocsFrom(Expr *e) {
15194     Loc = e->getExprLoc();
15195     Range = e->getSourceRange();
15196   }
15197 };
15198 
15199 } // namespace
15200 
15201 /// Consider whether capturing the given variable can possibly lead to
15202 /// a retain cycle.
15203 static bool considerVariable(VarDecl *var, Expr *ref, RetainCycleOwner &owner) {
15204   // In ARC, it's captured strongly iff the variable has __strong
15205   // lifetime.  In MRR, it's captured strongly if the variable is
15206   // __block and has an appropriate type.
15207   if (var->getType().getObjCLifetime() != Qualifiers::OCL_Strong)
15208     return false;
15209 
15210   owner.Variable = var;
15211   if (ref)
15212     owner.setLocsFrom(ref);
15213   return true;
15214 }
15215 
15216 static bool findRetainCycleOwner(Sema &S, Expr *e, RetainCycleOwner &owner) {
15217   while (true) {
15218     e = e->IgnoreParens();
15219     if (CastExpr *cast = dyn_cast<CastExpr>(e)) {
15220       switch (cast->getCastKind()) {
15221       case CK_BitCast:
15222       case CK_LValueBitCast:
15223       case CK_LValueToRValue:
15224       case CK_ARCReclaimReturnedObject:
15225         e = cast->getSubExpr();
15226         continue;
15227 
15228       default:
15229         return false;
15230       }
15231     }
15232 
15233     if (ObjCIvarRefExpr *ref = dyn_cast<ObjCIvarRefExpr>(e)) {
15234       ObjCIvarDecl *ivar = ref->getDecl();
15235       if (ivar->getType().getObjCLifetime() != Qualifiers::OCL_Strong)
15236         return false;
15237 
15238       // Try to find a retain cycle in the base.
15239       if (!findRetainCycleOwner(S, ref->getBase(), owner))
15240         return false;
15241 
15242       if (ref->isFreeIvar()) owner.setLocsFrom(ref);
15243       owner.Indirect = true;
15244       return true;
15245     }
15246 
15247     if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(e)) {
15248       VarDecl *var = dyn_cast<VarDecl>(ref->getDecl());
15249       if (!var) return false;
15250       return considerVariable(var, ref, owner);
15251     }
15252 
15253     if (MemberExpr *member = dyn_cast<MemberExpr>(e)) {
15254       if (member->isArrow()) return false;
15255 
15256       // Don't count this as an indirect ownership.
15257       e = member->getBase();
15258       continue;
15259     }
15260 
15261     if (PseudoObjectExpr *pseudo = dyn_cast<PseudoObjectExpr>(e)) {
15262       // Only pay attention to pseudo-objects on property references.
15263       ObjCPropertyRefExpr *pre
15264         = dyn_cast<ObjCPropertyRefExpr>(pseudo->getSyntacticForm()
15265                                               ->IgnoreParens());
15266       if (!pre) return false;
15267       if (pre->isImplicitProperty()) return false;
15268       ObjCPropertyDecl *property = pre->getExplicitProperty();
15269       if (!property->isRetaining() &&
15270           !(property->getPropertyIvarDecl() &&
15271             property->getPropertyIvarDecl()->getType()
15272               .getObjCLifetime() == Qualifiers::OCL_Strong))
15273           return false;
15274 
15275       owner.Indirect = true;
15276       if (pre->isSuperReceiver()) {
15277         owner.Variable = S.getCurMethodDecl()->getSelfDecl();
15278         if (!owner.Variable)
15279           return false;
15280         owner.Loc = pre->getLocation();
15281         owner.Range = pre->getSourceRange();
15282         return true;
15283       }
15284       e = const_cast<Expr*>(cast<OpaqueValueExpr>(pre->getBase())
15285                               ->getSourceExpr());
15286       continue;
15287     }
15288 
15289     // Array ivars?
15290 
15291     return false;
15292   }
15293 }
15294 
15295 namespace {
15296 
15297   struct FindCaptureVisitor : EvaluatedExprVisitor<FindCaptureVisitor> {
15298     ASTContext &Context;
15299     VarDecl *Variable;
15300     Expr *Capturer = nullptr;
15301     bool VarWillBeReased = false;
15302 
15303     FindCaptureVisitor(ASTContext &Context, VarDecl *variable)
15304         : EvaluatedExprVisitor<FindCaptureVisitor>(Context),
15305           Context(Context), Variable(variable) {}
15306 
15307     void VisitDeclRefExpr(DeclRefExpr *ref) {
15308       if (ref->getDecl() == Variable && !Capturer)
15309         Capturer = ref;
15310     }
15311 
15312     void VisitObjCIvarRefExpr(ObjCIvarRefExpr *ref) {
15313       if (Capturer) return;
15314       Visit(ref->getBase());
15315       if (Capturer && ref->isFreeIvar())
15316         Capturer = ref;
15317     }
15318 
15319     void VisitBlockExpr(BlockExpr *block) {
15320       // Look inside nested blocks
15321       if (block->getBlockDecl()->capturesVariable(Variable))
15322         Visit(block->getBlockDecl()->getBody());
15323     }
15324 
15325     void VisitOpaqueValueExpr(OpaqueValueExpr *OVE) {
15326       if (Capturer) return;
15327       if (OVE->getSourceExpr())
15328         Visit(OVE->getSourceExpr());
15329     }
15330 
15331     void VisitBinaryOperator(BinaryOperator *BinOp) {
15332       if (!Variable || VarWillBeReased || BinOp->getOpcode() != BO_Assign)
15333         return;
15334       Expr *LHS = BinOp->getLHS();
15335       if (const DeclRefExpr *DRE = dyn_cast_or_null<DeclRefExpr>(LHS)) {
15336         if (DRE->getDecl() != Variable)
15337           return;
15338         if (Expr *RHS = BinOp->getRHS()) {
15339           RHS = RHS->IgnoreParenCasts();
15340           Optional<llvm::APSInt> Value;
15341           VarWillBeReased =
15342               (RHS && (Value = RHS->getIntegerConstantExpr(Context)) &&
15343                *Value == 0);
15344         }
15345       }
15346     }
15347   };
15348 
15349 } // namespace
15350 
15351 /// Check whether the given argument is a block which captures a
15352 /// variable.
15353 static Expr *findCapturingExpr(Sema &S, Expr *e, RetainCycleOwner &owner) {
15354   assert(owner.Variable && owner.Loc.isValid());
15355 
15356   e = e->IgnoreParenCasts();
15357 
15358   // Look through [^{...} copy] and Block_copy(^{...}).
15359   if (ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(e)) {
15360     Selector Cmd = ME->getSelector();
15361     if (Cmd.isUnarySelector() && Cmd.getNameForSlot(0) == "copy") {
15362       e = ME->getInstanceReceiver();
15363       if (!e)
15364         return nullptr;
15365       e = e->IgnoreParenCasts();
15366     }
15367   } else if (CallExpr *CE = dyn_cast<CallExpr>(e)) {
15368     if (CE->getNumArgs() == 1) {
15369       FunctionDecl *Fn = dyn_cast_or_null<FunctionDecl>(CE->getCalleeDecl());
15370       if (Fn) {
15371         const IdentifierInfo *FnI = Fn->getIdentifier();
15372         if (FnI && FnI->isStr("_Block_copy")) {
15373           e = CE->getArg(0)->IgnoreParenCasts();
15374         }
15375       }
15376     }
15377   }
15378 
15379   BlockExpr *block = dyn_cast<BlockExpr>(e);
15380   if (!block || !block->getBlockDecl()->capturesVariable(owner.Variable))
15381     return nullptr;
15382 
15383   FindCaptureVisitor visitor(S.Context, owner.Variable);
15384   visitor.Visit(block->getBlockDecl()->getBody());
15385   return visitor.VarWillBeReased ? nullptr : visitor.Capturer;
15386 }
15387 
15388 static void diagnoseRetainCycle(Sema &S, Expr *capturer,
15389                                 RetainCycleOwner &owner) {
15390   assert(capturer);
15391   assert(owner.Variable && owner.Loc.isValid());
15392 
15393   S.Diag(capturer->getExprLoc(), diag::warn_arc_retain_cycle)
15394     << owner.Variable << capturer->getSourceRange();
15395   S.Diag(owner.Loc, diag::note_arc_retain_cycle_owner)
15396     << owner.Indirect << owner.Range;
15397 }
15398 
15399 /// Check for a keyword selector that starts with the word 'add' or
15400 /// 'set'.
15401 static bool isSetterLikeSelector(Selector sel) {
15402   if (sel.isUnarySelector()) return false;
15403 
15404   StringRef str = sel.getNameForSlot(0);
15405   while (!str.empty() && str.front() == '_') str = str.substr(1);
15406   if (str.startswith("set"))
15407     str = str.substr(3);
15408   else if (str.startswith("add")) {
15409     // Specially allow 'addOperationWithBlock:'.
15410     if (sel.getNumArgs() == 1 && str.startswith("addOperationWithBlock"))
15411       return false;
15412     str = str.substr(3);
15413   }
15414   else
15415     return false;
15416 
15417   if (str.empty()) return true;
15418   return !isLowercase(str.front());
15419 }
15420 
15421 static Optional<int> GetNSMutableArrayArgumentIndex(Sema &S,
15422                                                     ObjCMessageExpr *Message) {
15423   bool IsMutableArray = S.NSAPIObj->isSubclassOfNSClass(
15424                                                 Message->getReceiverInterface(),
15425                                                 NSAPI::ClassId_NSMutableArray);
15426   if (!IsMutableArray) {
15427     return None;
15428   }
15429 
15430   Selector Sel = Message->getSelector();
15431 
15432   Optional<NSAPI::NSArrayMethodKind> MKOpt =
15433     S.NSAPIObj->getNSArrayMethodKind(Sel);
15434   if (!MKOpt) {
15435     return None;
15436   }
15437 
15438   NSAPI::NSArrayMethodKind MK = *MKOpt;
15439 
15440   switch (MK) {
15441     case NSAPI::NSMutableArr_addObject:
15442     case NSAPI::NSMutableArr_insertObjectAtIndex:
15443     case NSAPI::NSMutableArr_setObjectAtIndexedSubscript:
15444       return 0;
15445     case NSAPI::NSMutableArr_replaceObjectAtIndex:
15446       return 1;
15447 
15448     default:
15449       return None;
15450   }
15451 
15452   return None;
15453 }
15454 
15455 static
15456 Optional<int> GetNSMutableDictionaryArgumentIndex(Sema &S,
15457                                                   ObjCMessageExpr *Message) {
15458   bool IsMutableDictionary = S.NSAPIObj->isSubclassOfNSClass(
15459                                             Message->getReceiverInterface(),
15460                                             NSAPI::ClassId_NSMutableDictionary);
15461   if (!IsMutableDictionary) {
15462     return None;
15463   }
15464 
15465   Selector Sel = Message->getSelector();
15466 
15467   Optional<NSAPI::NSDictionaryMethodKind> MKOpt =
15468     S.NSAPIObj->getNSDictionaryMethodKind(Sel);
15469   if (!MKOpt) {
15470     return None;
15471   }
15472 
15473   NSAPI::NSDictionaryMethodKind MK = *MKOpt;
15474 
15475   switch (MK) {
15476     case NSAPI::NSMutableDict_setObjectForKey:
15477     case NSAPI::NSMutableDict_setValueForKey:
15478     case NSAPI::NSMutableDict_setObjectForKeyedSubscript:
15479       return 0;
15480 
15481     default:
15482       return None;
15483   }
15484 
15485   return None;
15486 }
15487 
15488 static Optional<int> GetNSSetArgumentIndex(Sema &S, ObjCMessageExpr *Message) {
15489   bool IsMutableSet = S.NSAPIObj->isSubclassOfNSClass(
15490                                                 Message->getReceiverInterface(),
15491                                                 NSAPI::ClassId_NSMutableSet);
15492 
15493   bool IsMutableOrderedSet = S.NSAPIObj->isSubclassOfNSClass(
15494                                             Message->getReceiverInterface(),
15495                                             NSAPI::ClassId_NSMutableOrderedSet);
15496   if (!IsMutableSet && !IsMutableOrderedSet) {
15497     return None;
15498   }
15499 
15500   Selector Sel = Message->getSelector();
15501 
15502   Optional<NSAPI::NSSetMethodKind> MKOpt = S.NSAPIObj->getNSSetMethodKind(Sel);
15503   if (!MKOpt) {
15504     return None;
15505   }
15506 
15507   NSAPI::NSSetMethodKind MK = *MKOpt;
15508 
15509   switch (MK) {
15510     case NSAPI::NSMutableSet_addObject:
15511     case NSAPI::NSOrderedSet_setObjectAtIndex:
15512     case NSAPI::NSOrderedSet_setObjectAtIndexedSubscript:
15513     case NSAPI::NSOrderedSet_insertObjectAtIndex:
15514       return 0;
15515     case NSAPI::NSOrderedSet_replaceObjectAtIndexWithObject:
15516       return 1;
15517   }
15518 
15519   return None;
15520 }
15521 
15522 void Sema::CheckObjCCircularContainer(ObjCMessageExpr *Message) {
15523   if (!Message->isInstanceMessage()) {
15524     return;
15525   }
15526 
15527   Optional<int> ArgOpt;
15528 
15529   if (!(ArgOpt = GetNSMutableArrayArgumentIndex(*this, Message)) &&
15530       !(ArgOpt = GetNSMutableDictionaryArgumentIndex(*this, Message)) &&
15531       !(ArgOpt = GetNSSetArgumentIndex(*this, Message))) {
15532     return;
15533   }
15534 
15535   int ArgIndex = *ArgOpt;
15536 
15537   Expr *Arg = Message->getArg(ArgIndex)->IgnoreImpCasts();
15538   if (OpaqueValueExpr *OE = dyn_cast<OpaqueValueExpr>(Arg)) {
15539     Arg = OE->getSourceExpr()->IgnoreImpCasts();
15540   }
15541 
15542   if (Message->getReceiverKind() == ObjCMessageExpr::SuperInstance) {
15543     if (DeclRefExpr *ArgRE = dyn_cast<DeclRefExpr>(Arg)) {
15544       if (ArgRE->isObjCSelfExpr()) {
15545         Diag(Message->getSourceRange().getBegin(),
15546              diag::warn_objc_circular_container)
15547           << ArgRE->getDecl() << StringRef("'super'");
15548       }
15549     }
15550   } else {
15551     Expr *Receiver = Message->getInstanceReceiver()->IgnoreImpCasts();
15552 
15553     if (OpaqueValueExpr *OE = dyn_cast<OpaqueValueExpr>(Receiver)) {
15554       Receiver = OE->getSourceExpr()->IgnoreImpCasts();
15555     }
15556 
15557     if (DeclRefExpr *ReceiverRE = dyn_cast<DeclRefExpr>(Receiver)) {
15558       if (DeclRefExpr *ArgRE = dyn_cast<DeclRefExpr>(Arg)) {
15559         if (ReceiverRE->getDecl() == ArgRE->getDecl()) {
15560           ValueDecl *Decl = ReceiverRE->getDecl();
15561           Diag(Message->getSourceRange().getBegin(),
15562                diag::warn_objc_circular_container)
15563             << Decl << Decl;
15564           if (!ArgRE->isObjCSelfExpr()) {
15565             Diag(Decl->getLocation(),
15566                  diag::note_objc_circular_container_declared_here)
15567               << Decl;
15568           }
15569         }
15570       }
15571     } else if (ObjCIvarRefExpr *IvarRE = dyn_cast<ObjCIvarRefExpr>(Receiver)) {
15572       if (ObjCIvarRefExpr *IvarArgRE = dyn_cast<ObjCIvarRefExpr>(Arg)) {
15573         if (IvarRE->getDecl() == IvarArgRE->getDecl()) {
15574           ObjCIvarDecl *Decl = IvarRE->getDecl();
15575           Diag(Message->getSourceRange().getBegin(),
15576                diag::warn_objc_circular_container)
15577             << Decl << Decl;
15578           Diag(Decl->getLocation(),
15579                diag::note_objc_circular_container_declared_here)
15580             << Decl;
15581         }
15582       }
15583     }
15584   }
15585 }
15586 
15587 /// Check a message send to see if it's likely to cause a retain cycle.
15588 void Sema::checkRetainCycles(ObjCMessageExpr *msg) {
15589   // Only check instance methods whose selector looks like a setter.
15590   if (!msg->isInstanceMessage() || !isSetterLikeSelector(msg->getSelector()))
15591     return;
15592 
15593   // Try to find a variable that the receiver is strongly owned by.
15594   RetainCycleOwner owner;
15595   if (msg->getReceiverKind() == ObjCMessageExpr::Instance) {
15596     if (!findRetainCycleOwner(*this, msg->getInstanceReceiver(), owner))
15597       return;
15598   } else {
15599     assert(msg->getReceiverKind() == ObjCMessageExpr::SuperInstance);
15600     owner.Variable = getCurMethodDecl()->getSelfDecl();
15601     owner.Loc = msg->getSuperLoc();
15602     owner.Range = msg->getSuperLoc();
15603   }
15604 
15605   // Check whether the receiver is captured by any of the arguments.
15606   const ObjCMethodDecl *MD = msg->getMethodDecl();
15607   for (unsigned i = 0, e = msg->getNumArgs(); i != e; ++i) {
15608     if (Expr *capturer = findCapturingExpr(*this, msg->getArg(i), owner)) {
15609       // noescape blocks should not be retained by the method.
15610       if (MD && MD->parameters()[i]->hasAttr<NoEscapeAttr>())
15611         continue;
15612       return diagnoseRetainCycle(*this, capturer, owner);
15613     }
15614   }
15615 }
15616 
15617 /// Check a property assign to see if it's likely to cause a retain cycle.
15618 void Sema::checkRetainCycles(Expr *receiver, Expr *argument) {
15619   RetainCycleOwner owner;
15620   if (!findRetainCycleOwner(*this, receiver, owner))
15621     return;
15622 
15623   if (Expr *capturer = findCapturingExpr(*this, argument, owner))
15624     diagnoseRetainCycle(*this, capturer, owner);
15625 }
15626 
15627 void Sema::checkRetainCycles(VarDecl *Var, Expr *Init) {
15628   RetainCycleOwner Owner;
15629   if (!considerVariable(Var, /*DeclRefExpr=*/nullptr, Owner))
15630     return;
15631 
15632   // Because we don't have an expression for the variable, we have to set the
15633   // location explicitly here.
15634   Owner.Loc = Var->getLocation();
15635   Owner.Range = Var->getSourceRange();
15636 
15637   if (Expr *Capturer = findCapturingExpr(*this, Init, Owner))
15638     diagnoseRetainCycle(*this, Capturer, Owner);
15639 }
15640 
15641 static bool checkUnsafeAssignLiteral(Sema &S, SourceLocation Loc,
15642                                      Expr *RHS, bool isProperty) {
15643   // Check if RHS is an Objective-C object literal, which also can get
15644   // immediately zapped in a weak reference.  Note that we explicitly
15645   // allow ObjCStringLiterals, since those are designed to never really die.
15646   RHS = RHS->IgnoreParenImpCasts();
15647 
15648   // This enum needs to match with the 'select' in
15649   // warn_objc_arc_literal_assign (off-by-1).
15650   Sema::ObjCLiteralKind Kind = S.CheckLiteralKind(RHS);
15651   if (Kind == Sema::LK_String || Kind == Sema::LK_None)
15652     return false;
15653 
15654   S.Diag(Loc, diag::warn_arc_literal_assign)
15655     << (unsigned) Kind
15656     << (isProperty ? 0 : 1)
15657     << RHS->getSourceRange();
15658 
15659   return true;
15660 }
15661 
15662 static bool checkUnsafeAssignObject(Sema &S, SourceLocation Loc,
15663                                     Qualifiers::ObjCLifetime LT,
15664                                     Expr *RHS, bool isProperty) {
15665   // Strip off any implicit cast added to get to the one ARC-specific.
15666   while (ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(RHS)) {
15667     if (cast->getCastKind() == CK_ARCConsumeObject) {
15668       S.Diag(Loc, diag::warn_arc_retained_assign)
15669         << (LT == Qualifiers::OCL_ExplicitNone)
15670         << (isProperty ? 0 : 1)
15671         << RHS->getSourceRange();
15672       return true;
15673     }
15674     RHS = cast->getSubExpr();
15675   }
15676 
15677   if (LT == Qualifiers::OCL_Weak &&
15678       checkUnsafeAssignLiteral(S, Loc, RHS, isProperty))
15679     return true;
15680 
15681   return false;
15682 }
15683 
15684 bool Sema::checkUnsafeAssigns(SourceLocation Loc,
15685                               QualType LHS, Expr *RHS) {
15686   Qualifiers::ObjCLifetime LT = LHS.getObjCLifetime();
15687 
15688   if (LT != Qualifiers::OCL_Weak && LT != Qualifiers::OCL_ExplicitNone)
15689     return false;
15690 
15691   if (checkUnsafeAssignObject(*this, Loc, LT, RHS, false))
15692     return true;
15693 
15694   return false;
15695 }
15696 
15697 void Sema::checkUnsafeExprAssigns(SourceLocation Loc,
15698                               Expr *LHS, Expr *RHS) {
15699   QualType LHSType;
15700   // PropertyRef on LHS type need be directly obtained from
15701   // its declaration as it has a PseudoType.
15702   ObjCPropertyRefExpr *PRE
15703     = dyn_cast<ObjCPropertyRefExpr>(LHS->IgnoreParens());
15704   if (PRE && !PRE->isImplicitProperty()) {
15705     const ObjCPropertyDecl *PD = PRE->getExplicitProperty();
15706     if (PD)
15707       LHSType = PD->getType();
15708   }
15709 
15710   if (LHSType.isNull())
15711     LHSType = LHS->getType();
15712 
15713   Qualifiers::ObjCLifetime LT = LHSType.getObjCLifetime();
15714 
15715   if (LT == Qualifiers::OCL_Weak) {
15716     if (!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, Loc))
15717       getCurFunction()->markSafeWeakUse(LHS);
15718   }
15719 
15720   if (checkUnsafeAssigns(Loc, LHSType, RHS))
15721     return;
15722 
15723   // FIXME. Check for other life times.
15724   if (LT != Qualifiers::OCL_None)
15725     return;
15726 
15727   if (PRE) {
15728     if (PRE->isImplicitProperty())
15729       return;
15730     const ObjCPropertyDecl *PD = PRE->getExplicitProperty();
15731     if (!PD)
15732       return;
15733 
15734     unsigned Attributes = PD->getPropertyAttributes();
15735     if (Attributes & ObjCPropertyAttribute::kind_assign) {
15736       // when 'assign' attribute was not explicitly specified
15737       // by user, ignore it and rely on property type itself
15738       // for lifetime info.
15739       unsigned AsWrittenAttr = PD->getPropertyAttributesAsWritten();
15740       if (!(AsWrittenAttr & ObjCPropertyAttribute::kind_assign) &&
15741           LHSType->isObjCRetainableType())
15742         return;
15743 
15744       while (ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(RHS)) {
15745         if (cast->getCastKind() == CK_ARCConsumeObject) {
15746           Diag(Loc, diag::warn_arc_retained_property_assign)
15747           << RHS->getSourceRange();
15748           return;
15749         }
15750         RHS = cast->getSubExpr();
15751       }
15752     } else if (Attributes & ObjCPropertyAttribute::kind_weak) {
15753       if (checkUnsafeAssignObject(*this, Loc, Qualifiers::OCL_Weak, RHS, true))
15754         return;
15755     }
15756   }
15757 }
15758 
15759 //===--- CHECK: Empty statement body (-Wempty-body) ---------------------===//
15760 
15761 static bool ShouldDiagnoseEmptyStmtBody(const SourceManager &SourceMgr,
15762                                         SourceLocation StmtLoc,
15763                                         const NullStmt *Body) {
15764   // Do not warn if the body is a macro that expands to nothing, e.g:
15765   //
15766   // #define CALL(x)
15767   // if (condition)
15768   //   CALL(0);
15769   if (Body->hasLeadingEmptyMacro())
15770     return false;
15771 
15772   // Get line numbers of statement and body.
15773   bool StmtLineInvalid;
15774   unsigned StmtLine = SourceMgr.getPresumedLineNumber(StmtLoc,
15775                                                       &StmtLineInvalid);
15776   if (StmtLineInvalid)
15777     return false;
15778 
15779   bool BodyLineInvalid;
15780   unsigned BodyLine = SourceMgr.getSpellingLineNumber(Body->getSemiLoc(),
15781                                                       &BodyLineInvalid);
15782   if (BodyLineInvalid)
15783     return false;
15784 
15785   // Warn if null statement and body are on the same line.
15786   if (StmtLine != BodyLine)
15787     return false;
15788 
15789   return true;
15790 }
15791 
15792 void Sema::DiagnoseEmptyStmtBody(SourceLocation StmtLoc,
15793                                  const Stmt *Body,
15794                                  unsigned DiagID) {
15795   // Since this is a syntactic check, don't emit diagnostic for template
15796   // instantiations, this just adds noise.
15797   if (CurrentInstantiationScope)
15798     return;
15799 
15800   // The body should be a null statement.
15801   const NullStmt *NBody = dyn_cast<NullStmt>(Body);
15802   if (!NBody)
15803     return;
15804 
15805   // Do the usual checks.
15806   if (!ShouldDiagnoseEmptyStmtBody(SourceMgr, StmtLoc, NBody))
15807     return;
15808 
15809   Diag(NBody->getSemiLoc(), DiagID);
15810   Diag(NBody->getSemiLoc(), diag::note_empty_body_on_separate_line);
15811 }
15812 
15813 void Sema::DiagnoseEmptyLoopBody(const Stmt *S,
15814                                  const Stmt *PossibleBody) {
15815   assert(!CurrentInstantiationScope); // Ensured by caller
15816 
15817   SourceLocation StmtLoc;
15818   const Stmt *Body;
15819   unsigned DiagID;
15820   if (const ForStmt *FS = dyn_cast<ForStmt>(S)) {
15821     StmtLoc = FS->getRParenLoc();
15822     Body = FS->getBody();
15823     DiagID = diag::warn_empty_for_body;
15824   } else if (const WhileStmt *WS = dyn_cast<WhileStmt>(S)) {
15825     StmtLoc = WS->getCond()->getSourceRange().getEnd();
15826     Body = WS->getBody();
15827     DiagID = diag::warn_empty_while_body;
15828   } else
15829     return; // Neither `for' nor `while'.
15830 
15831   // The body should be a null statement.
15832   const NullStmt *NBody = dyn_cast<NullStmt>(Body);
15833   if (!NBody)
15834     return;
15835 
15836   // Skip expensive checks if diagnostic is disabled.
15837   if (Diags.isIgnored(DiagID, NBody->getSemiLoc()))
15838     return;
15839 
15840   // Do the usual checks.
15841   if (!ShouldDiagnoseEmptyStmtBody(SourceMgr, StmtLoc, NBody))
15842     return;
15843 
15844   // `for(...);' and `while(...);' are popular idioms, so in order to keep
15845   // noise level low, emit diagnostics only if for/while is followed by a
15846   // CompoundStmt, e.g.:
15847   //    for (int i = 0; i < n; i++);
15848   //    {
15849   //      a(i);
15850   //    }
15851   // or if for/while is followed by a statement with more indentation
15852   // than for/while itself:
15853   //    for (int i = 0; i < n; i++);
15854   //      a(i);
15855   bool ProbableTypo = isa<CompoundStmt>(PossibleBody);
15856   if (!ProbableTypo) {
15857     bool BodyColInvalid;
15858     unsigned BodyCol = SourceMgr.getPresumedColumnNumber(
15859         PossibleBody->getBeginLoc(), &BodyColInvalid);
15860     if (BodyColInvalid)
15861       return;
15862 
15863     bool StmtColInvalid;
15864     unsigned StmtCol =
15865         SourceMgr.getPresumedColumnNumber(S->getBeginLoc(), &StmtColInvalid);
15866     if (StmtColInvalid)
15867       return;
15868 
15869     if (BodyCol > StmtCol)
15870       ProbableTypo = true;
15871   }
15872 
15873   if (ProbableTypo) {
15874     Diag(NBody->getSemiLoc(), DiagID);
15875     Diag(NBody->getSemiLoc(), diag::note_empty_body_on_separate_line);
15876   }
15877 }
15878 
15879 //===--- CHECK: Warn on self move with std::move. -------------------------===//
15880 
15881 /// DiagnoseSelfMove - Emits a warning if a value is moved to itself.
15882 void Sema::DiagnoseSelfMove(const Expr *LHSExpr, const Expr *RHSExpr,
15883                              SourceLocation OpLoc) {
15884   if (Diags.isIgnored(diag::warn_sizeof_pointer_expr_memaccess, OpLoc))
15885     return;
15886 
15887   if (inTemplateInstantiation())
15888     return;
15889 
15890   // Strip parens and casts away.
15891   LHSExpr = LHSExpr->IgnoreParenImpCasts();
15892   RHSExpr = RHSExpr->IgnoreParenImpCasts();
15893 
15894   // Check for a call expression
15895   const CallExpr *CE = dyn_cast<CallExpr>(RHSExpr);
15896   if (!CE || CE->getNumArgs() != 1)
15897     return;
15898 
15899   // Check for a call to std::move
15900   if (!CE->isCallToStdMove())
15901     return;
15902 
15903   // Get argument from std::move
15904   RHSExpr = CE->getArg(0);
15905 
15906   const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(LHSExpr);
15907   const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(RHSExpr);
15908 
15909   // Two DeclRefExpr's, check that the decls are the same.
15910   if (LHSDeclRef && RHSDeclRef) {
15911     if (!LHSDeclRef->getDecl() || !RHSDeclRef->getDecl())
15912       return;
15913     if (LHSDeclRef->getDecl()->getCanonicalDecl() !=
15914         RHSDeclRef->getDecl()->getCanonicalDecl())
15915       return;
15916 
15917     Diag(OpLoc, diag::warn_self_move) << LHSExpr->getType()
15918                                         << LHSExpr->getSourceRange()
15919                                         << RHSExpr->getSourceRange();
15920     return;
15921   }
15922 
15923   // Member variables require a different approach to check for self moves.
15924   // MemberExpr's are the same if every nested MemberExpr refers to the same
15925   // Decl and that the base Expr's are DeclRefExpr's with the same Decl or
15926   // the base Expr's are CXXThisExpr's.
15927   const Expr *LHSBase = LHSExpr;
15928   const Expr *RHSBase = RHSExpr;
15929   const MemberExpr *LHSME = dyn_cast<MemberExpr>(LHSExpr);
15930   const MemberExpr *RHSME = dyn_cast<MemberExpr>(RHSExpr);
15931   if (!LHSME || !RHSME)
15932     return;
15933 
15934   while (LHSME && RHSME) {
15935     if (LHSME->getMemberDecl()->getCanonicalDecl() !=
15936         RHSME->getMemberDecl()->getCanonicalDecl())
15937       return;
15938 
15939     LHSBase = LHSME->getBase();
15940     RHSBase = RHSME->getBase();
15941     LHSME = dyn_cast<MemberExpr>(LHSBase);
15942     RHSME = dyn_cast<MemberExpr>(RHSBase);
15943   }
15944 
15945   LHSDeclRef = dyn_cast<DeclRefExpr>(LHSBase);
15946   RHSDeclRef = dyn_cast<DeclRefExpr>(RHSBase);
15947   if (LHSDeclRef && RHSDeclRef) {
15948     if (!LHSDeclRef->getDecl() || !RHSDeclRef->getDecl())
15949       return;
15950     if (LHSDeclRef->getDecl()->getCanonicalDecl() !=
15951         RHSDeclRef->getDecl()->getCanonicalDecl())
15952       return;
15953 
15954     Diag(OpLoc, diag::warn_self_move) << LHSExpr->getType()
15955                                         << LHSExpr->getSourceRange()
15956                                         << RHSExpr->getSourceRange();
15957     return;
15958   }
15959 
15960   if (isa<CXXThisExpr>(LHSBase) && isa<CXXThisExpr>(RHSBase))
15961     Diag(OpLoc, diag::warn_self_move) << LHSExpr->getType()
15962                                         << LHSExpr->getSourceRange()
15963                                         << RHSExpr->getSourceRange();
15964 }
15965 
15966 //===--- Layout compatibility ----------------------------------------------//
15967 
15968 static bool isLayoutCompatible(ASTContext &C, QualType T1, QualType T2);
15969 
15970 /// Check if two enumeration types are layout-compatible.
15971 static bool isLayoutCompatible(ASTContext &C, EnumDecl *ED1, EnumDecl *ED2) {
15972   // C++11 [dcl.enum] p8:
15973   // Two enumeration types are layout-compatible if they have the same
15974   // underlying type.
15975   return ED1->isComplete() && ED2->isComplete() &&
15976          C.hasSameType(ED1->getIntegerType(), ED2->getIntegerType());
15977 }
15978 
15979 /// Check if two fields are layout-compatible.
15980 static bool isLayoutCompatible(ASTContext &C, FieldDecl *Field1,
15981                                FieldDecl *Field2) {
15982   if (!isLayoutCompatible(C, Field1->getType(), Field2->getType()))
15983     return false;
15984 
15985   if (Field1->isBitField() != Field2->isBitField())
15986     return false;
15987 
15988   if (Field1->isBitField()) {
15989     // Make sure that the bit-fields are the same length.
15990     unsigned Bits1 = Field1->getBitWidthValue(C);
15991     unsigned Bits2 = Field2->getBitWidthValue(C);
15992 
15993     if (Bits1 != Bits2)
15994       return false;
15995   }
15996 
15997   return true;
15998 }
15999 
16000 /// Check if two standard-layout structs are layout-compatible.
16001 /// (C++11 [class.mem] p17)
16002 static bool isLayoutCompatibleStruct(ASTContext &C, RecordDecl *RD1,
16003                                      RecordDecl *RD2) {
16004   // If both records are C++ classes, check that base classes match.
16005   if (const CXXRecordDecl *D1CXX = dyn_cast<CXXRecordDecl>(RD1)) {
16006     // If one of records is a CXXRecordDecl we are in C++ mode,
16007     // thus the other one is a CXXRecordDecl, too.
16008     const CXXRecordDecl *D2CXX = cast<CXXRecordDecl>(RD2);
16009     // Check number of base classes.
16010     if (D1CXX->getNumBases() != D2CXX->getNumBases())
16011       return false;
16012 
16013     // Check the base classes.
16014     for (CXXRecordDecl::base_class_const_iterator
16015                Base1 = D1CXX->bases_begin(),
16016            BaseEnd1 = D1CXX->bases_end(),
16017               Base2 = D2CXX->bases_begin();
16018          Base1 != BaseEnd1;
16019          ++Base1, ++Base2) {
16020       if (!isLayoutCompatible(C, Base1->getType(), Base2->getType()))
16021         return false;
16022     }
16023   } else if (const CXXRecordDecl *D2CXX = dyn_cast<CXXRecordDecl>(RD2)) {
16024     // If only RD2 is a C++ class, it should have zero base classes.
16025     if (D2CXX->getNumBases() > 0)
16026       return false;
16027   }
16028 
16029   // Check the fields.
16030   RecordDecl::field_iterator Field2 = RD2->field_begin(),
16031                              Field2End = RD2->field_end(),
16032                              Field1 = RD1->field_begin(),
16033                              Field1End = RD1->field_end();
16034   for ( ; Field1 != Field1End && Field2 != Field2End; ++Field1, ++Field2) {
16035     if (!isLayoutCompatible(C, *Field1, *Field2))
16036       return false;
16037   }
16038   if (Field1 != Field1End || Field2 != Field2End)
16039     return false;
16040 
16041   return true;
16042 }
16043 
16044 /// Check if two standard-layout unions are layout-compatible.
16045 /// (C++11 [class.mem] p18)
16046 static bool isLayoutCompatibleUnion(ASTContext &C, RecordDecl *RD1,
16047                                     RecordDecl *RD2) {
16048   llvm::SmallPtrSet<FieldDecl *, 8> UnmatchedFields;
16049   for (auto *Field2 : RD2->fields())
16050     UnmatchedFields.insert(Field2);
16051 
16052   for (auto *Field1 : RD1->fields()) {
16053     llvm::SmallPtrSet<FieldDecl *, 8>::iterator
16054         I = UnmatchedFields.begin(),
16055         E = UnmatchedFields.end();
16056 
16057     for ( ; I != E; ++I) {
16058       if (isLayoutCompatible(C, Field1, *I)) {
16059         bool Result = UnmatchedFields.erase(*I);
16060         (void) Result;
16061         assert(Result);
16062         break;
16063       }
16064     }
16065     if (I == E)
16066       return false;
16067   }
16068 
16069   return UnmatchedFields.empty();
16070 }
16071 
16072 static bool isLayoutCompatible(ASTContext &C, RecordDecl *RD1,
16073                                RecordDecl *RD2) {
16074   if (RD1->isUnion() != RD2->isUnion())
16075     return false;
16076 
16077   if (RD1->isUnion())
16078     return isLayoutCompatibleUnion(C, RD1, RD2);
16079   else
16080     return isLayoutCompatibleStruct(C, RD1, RD2);
16081 }
16082 
16083 /// Check if two types are layout-compatible in C++11 sense.
16084 static bool isLayoutCompatible(ASTContext &C, QualType T1, QualType T2) {
16085   if (T1.isNull() || T2.isNull())
16086     return false;
16087 
16088   // C++11 [basic.types] p11:
16089   // If two types T1 and T2 are the same type, then T1 and T2 are
16090   // layout-compatible types.
16091   if (C.hasSameType(T1, T2))
16092     return true;
16093 
16094   T1 = T1.getCanonicalType().getUnqualifiedType();
16095   T2 = T2.getCanonicalType().getUnqualifiedType();
16096 
16097   const Type::TypeClass TC1 = T1->getTypeClass();
16098   const Type::TypeClass TC2 = T2->getTypeClass();
16099 
16100   if (TC1 != TC2)
16101     return false;
16102 
16103   if (TC1 == Type::Enum) {
16104     return isLayoutCompatible(C,
16105                               cast<EnumType>(T1)->getDecl(),
16106                               cast<EnumType>(T2)->getDecl());
16107   } else if (TC1 == Type::Record) {
16108     if (!T1->isStandardLayoutType() || !T2->isStandardLayoutType())
16109       return false;
16110 
16111     return isLayoutCompatible(C,
16112                               cast<RecordType>(T1)->getDecl(),
16113                               cast<RecordType>(T2)->getDecl());
16114   }
16115 
16116   return false;
16117 }
16118 
16119 //===--- CHECK: pointer_with_type_tag attribute: datatypes should match ----//
16120 
16121 /// Given a type tag expression find the type tag itself.
16122 ///
16123 /// \param TypeExpr Type tag expression, as it appears in user's code.
16124 ///
16125 /// \param VD Declaration of an identifier that appears in a type tag.
16126 ///
16127 /// \param MagicValue Type tag magic value.
16128 ///
16129 /// \param isConstantEvaluated whether the evalaution should be performed in
16130 
16131 /// constant context.
16132 static bool FindTypeTagExpr(const Expr *TypeExpr, const ASTContext &Ctx,
16133                             const ValueDecl **VD, uint64_t *MagicValue,
16134                             bool isConstantEvaluated) {
16135   while(true) {
16136     if (!TypeExpr)
16137       return false;
16138 
16139     TypeExpr = TypeExpr->IgnoreParenImpCasts()->IgnoreParenCasts();
16140 
16141     switch (TypeExpr->getStmtClass()) {
16142     case Stmt::UnaryOperatorClass: {
16143       const UnaryOperator *UO = cast<UnaryOperator>(TypeExpr);
16144       if (UO->getOpcode() == UO_AddrOf || UO->getOpcode() == UO_Deref) {
16145         TypeExpr = UO->getSubExpr();
16146         continue;
16147       }
16148       return false;
16149     }
16150 
16151     case Stmt::DeclRefExprClass: {
16152       const DeclRefExpr *DRE = cast<DeclRefExpr>(TypeExpr);
16153       *VD = DRE->getDecl();
16154       return true;
16155     }
16156 
16157     case Stmt::IntegerLiteralClass: {
16158       const IntegerLiteral *IL = cast<IntegerLiteral>(TypeExpr);
16159       llvm::APInt MagicValueAPInt = IL->getValue();
16160       if (MagicValueAPInt.getActiveBits() <= 64) {
16161         *MagicValue = MagicValueAPInt.getZExtValue();
16162         return true;
16163       } else
16164         return false;
16165     }
16166 
16167     case Stmt::BinaryConditionalOperatorClass:
16168     case Stmt::ConditionalOperatorClass: {
16169       const AbstractConditionalOperator *ACO =
16170           cast<AbstractConditionalOperator>(TypeExpr);
16171       bool Result;
16172       if (ACO->getCond()->EvaluateAsBooleanCondition(Result, Ctx,
16173                                                      isConstantEvaluated)) {
16174         if (Result)
16175           TypeExpr = ACO->getTrueExpr();
16176         else
16177           TypeExpr = ACO->getFalseExpr();
16178         continue;
16179       }
16180       return false;
16181     }
16182 
16183     case Stmt::BinaryOperatorClass: {
16184       const BinaryOperator *BO = cast<BinaryOperator>(TypeExpr);
16185       if (BO->getOpcode() == BO_Comma) {
16186         TypeExpr = BO->getRHS();
16187         continue;
16188       }
16189       return false;
16190     }
16191 
16192     default:
16193       return false;
16194     }
16195   }
16196 }
16197 
16198 /// Retrieve the C type corresponding to type tag TypeExpr.
16199 ///
16200 /// \param TypeExpr Expression that specifies a type tag.
16201 ///
16202 /// \param MagicValues Registered magic values.
16203 ///
16204 /// \param FoundWrongKind Set to true if a type tag was found, but of a wrong
16205 ///        kind.
16206 ///
16207 /// \param TypeInfo Information about the corresponding C type.
16208 ///
16209 /// \param isConstantEvaluated whether the evalaution should be performed in
16210 /// constant context.
16211 ///
16212 /// \returns true if the corresponding C type was found.
16213 static bool GetMatchingCType(
16214     const IdentifierInfo *ArgumentKind, const Expr *TypeExpr,
16215     const ASTContext &Ctx,
16216     const llvm::DenseMap<Sema::TypeTagMagicValue, Sema::TypeTagData>
16217         *MagicValues,
16218     bool &FoundWrongKind, Sema::TypeTagData &TypeInfo,
16219     bool isConstantEvaluated) {
16220   FoundWrongKind = false;
16221 
16222   // Variable declaration that has type_tag_for_datatype attribute.
16223   const ValueDecl *VD = nullptr;
16224 
16225   uint64_t MagicValue;
16226 
16227   if (!FindTypeTagExpr(TypeExpr, Ctx, &VD, &MagicValue, isConstantEvaluated))
16228     return false;
16229 
16230   if (VD) {
16231     if (TypeTagForDatatypeAttr *I = VD->getAttr<TypeTagForDatatypeAttr>()) {
16232       if (I->getArgumentKind() != ArgumentKind) {
16233         FoundWrongKind = true;
16234         return false;
16235       }
16236       TypeInfo.Type = I->getMatchingCType();
16237       TypeInfo.LayoutCompatible = I->getLayoutCompatible();
16238       TypeInfo.MustBeNull = I->getMustBeNull();
16239       return true;
16240     }
16241     return false;
16242   }
16243 
16244   if (!MagicValues)
16245     return false;
16246 
16247   llvm::DenseMap<Sema::TypeTagMagicValue,
16248                  Sema::TypeTagData>::const_iterator I =
16249       MagicValues->find(std::make_pair(ArgumentKind, MagicValue));
16250   if (I == MagicValues->end())
16251     return false;
16252 
16253   TypeInfo = I->second;
16254   return true;
16255 }
16256 
16257 void Sema::RegisterTypeTagForDatatype(const IdentifierInfo *ArgumentKind,
16258                                       uint64_t MagicValue, QualType Type,
16259                                       bool LayoutCompatible,
16260                                       bool MustBeNull) {
16261   if (!TypeTagForDatatypeMagicValues)
16262     TypeTagForDatatypeMagicValues.reset(
16263         new llvm::DenseMap<TypeTagMagicValue, TypeTagData>);
16264 
16265   TypeTagMagicValue Magic(ArgumentKind, MagicValue);
16266   (*TypeTagForDatatypeMagicValues)[Magic] =
16267       TypeTagData(Type, LayoutCompatible, MustBeNull);
16268 }
16269 
16270 static bool IsSameCharType(QualType T1, QualType T2) {
16271   const BuiltinType *BT1 = T1->getAs<BuiltinType>();
16272   if (!BT1)
16273     return false;
16274 
16275   const BuiltinType *BT2 = T2->getAs<BuiltinType>();
16276   if (!BT2)
16277     return false;
16278 
16279   BuiltinType::Kind T1Kind = BT1->getKind();
16280   BuiltinType::Kind T2Kind = BT2->getKind();
16281 
16282   return (T1Kind == BuiltinType::SChar  && T2Kind == BuiltinType::Char_S) ||
16283          (T1Kind == BuiltinType::UChar  && T2Kind == BuiltinType::Char_U) ||
16284          (T1Kind == BuiltinType::Char_U && T2Kind == BuiltinType::UChar) ||
16285          (T1Kind == BuiltinType::Char_S && T2Kind == BuiltinType::SChar);
16286 }
16287 
16288 void Sema::CheckArgumentWithTypeTag(const ArgumentWithTypeTagAttr *Attr,
16289                                     const ArrayRef<const Expr *> ExprArgs,
16290                                     SourceLocation CallSiteLoc) {
16291   const IdentifierInfo *ArgumentKind = Attr->getArgumentKind();
16292   bool IsPointerAttr = Attr->getIsPointer();
16293 
16294   // Retrieve the argument representing the 'type_tag'.
16295   unsigned TypeTagIdxAST = Attr->getTypeTagIdx().getASTIndex();
16296   if (TypeTagIdxAST >= ExprArgs.size()) {
16297     Diag(CallSiteLoc, diag::err_tag_index_out_of_range)
16298         << 0 << Attr->getTypeTagIdx().getSourceIndex();
16299     return;
16300   }
16301   const Expr *TypeTagExpr = ExprArgs[TypeTagIdxAST];
16302   bool FoundWrongKind;
16303   TypeTagData TypeInfo;
16304   if (!GetMatchingCType(ArgumentKind, TypeTagExpr, Context,
16305                         TypeTagForDatatypeMagicValues.get(), FoundWrongKind,
16306                         TypeInfo, isConstantEvaluated())) {
16307     if (FoundWrongKind)
16308       Diag(TypeTagExpr->getExprLoc(),
16309            diag::warn_type_tag_for_datatype_wrong_kind)
16310         << TypeTagExpr->getSourceRange();
16311     return;
16312   }
16313 
16314   // Retrieve the argument representing the 'arg_idx'.
16315   unsigned ArgumentIdxAST = Attr->getArgumentIdx().getASTIndex();
16316   if (ArgumentIdxAST >= ExprArgs.size()) {
16317     Diag(CallSiteLoc, diag::err_tag_index_out_of_range)
16318         << 1 << Attr->getArgumentIdx().getSourceIndex();
16319     return;
16320   }
16321   const Expr *ArgumentExpr = ExprArgs[ArgumentIdxAST];
16322   if (IsPointerAttr) {
16323     // Skip implicit cast of pointer to `void *' (as a function argument).
16324     if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgumentExpr))
16325       if (ICE->getType()->isVoidPointerType() &&
16326           ICE->getCastKind() == CK_BitCast)
16327         ArgumentExpr = ICE->getSubExpr();
16328   }
16329   QualType ArgumentType = ArgumentExpr->getType();
16330 
16331   // Passing a `void*' pointer shouldn't trigger a warning.
16332   if (IsPointerAttr && ArgumentType->isVoidPointerType())
16333     return;
16334 
16335   if (TypeInfo.MustBeNull) {
16336     // Type tag with matching void type requires a null pointer.
16337     if (!ArgumentExpr->isNullPointerConstant(Context,
16338                                              Expr::NPC_ValueDependentIsNotNull)) {
16339       Diag(ArgumentExpr->getExprLoc(),
16340            diag::warn_type_safety_null_pointer_required)
16341           << ArgumentKind->getName()
16342           << ArgumentExpr->getSourceRange()
16343           << TypeTagExpr->getSourceRange();
16344     }
16345     return;
16346   }
16347 
16348   QualType RequiredType = TypeInfo.Type;
16349   if (IsPointerAttr)
16350     RequiredType = Context.getPointerType(RequiredType);
16351 
16352   bool mismatch = false;
16353   if (!TypeInfo.LayoutCompatible) {
16354     mismatch = !Context.hasSameType(ArgumentType, RequiredType);
16355 
16356     // C++11 [basic.fundamental] p1:
16357     // Plain char, signed char, and unsigned char are three distinct types.
16358     //
16359     // But we treat plain `char' as equivalent to `signed char' or `unsigned
16360     // char' depending on the current char signedness mode.
16361     if (mismatch)
16362       if ((IsPointerAttr && IsSameCharType(ArgumentType->getPointeeType(),
16363                                            RequiredType->getPointeeType())) ||
16364           (!IsPointerAttr && IsSameCharType(ArgumentType, RequiredType)))
16365         mismatch = false;
16366   } else
16367     if (IsPointerAttr)
16368       mismatch = !isLayoutCompatible(Context,
16369                                      ArgumentType->getPointeeType(),
16370                                      RequiredType->getPointeeType());
16371     else
16372       mismatch = !isLayoutCompatible(Context, ArgumentType, RequiredType);
16373 
16374   if (mismatch)
16375     Diag(ArgumentExpr->getExprLoc(), diag::warn_type_safety_type_mismatch)
16376         << ArgumentType << ArgumentKind
16377         << TypeInfo.LayoutCompatible << RequiredType
16378         << ArgumentExpr->getSourceRange()
16379         << TypeTagExpr->getSourceRange();
16380 }
16381 
16382 void Sema::AddPotentialMisalignedMembers(Expr *E, RecordDecl *RD, ValueDecl *MD,
16383                                          CharUnits Alignment) {
16384   MisalignedMembers.emplace_back(E, RD, MD, Alignment);
16385 }
16386 
16387 void Sema::DiagnoseMisalignedMembers() {
16388   for (MisalignedMember &m : MisalignedMembers) {
16389     const NamedDecl *ND = m.RD;
16390     if (ND->getName().empty()) {
16391       if (const TypedefNameDecl *TD = m.RD->getTypedefNameForAnonDecl())
16392         ND = TD;
16393     }
16394     Diag(m.E->getBeginLoc(), diag::warn_taking_address_of_packed_member)
16395         << m.MD << ND << m.E->getSourceRange();
16396   }
16397   MisalignedMembers.clear();
16398 }
16399 
16400 void Sema::DiscardMisalignedMemberAddress(const Type *T, Expr *E) {
16401   E = E->IgnoreParens();
16402   if (!T->isPointerType() && !T->isIntegerType())
16403     return;
16404   if (isa<UnaryOperator>(E) &&
16405       cast<UnaryOperator>(E)->getOpcode() == UO_AddrOf) {
16406     auto *Op = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens();
16407     if (isa<MemberExpr>(Op)) {
16408       auto MA = llvm::find(MisalignedMembers, MisalignedMember(Op));
16409       if (MA != MisalignedMembers.end() &&
16410           (T->isIntegerType() ||
16411            (T->isPointerType() && (T->getPointeeType()->isIncompleteType() ||
16412                                    Context.getTypeAlignInChars(
16413                                        T->getPointeeType()) <= MA->Alignment))))
16414         MisalignedMembers.erase(MA);
16415     }
16416   }
16417 }
16418 
16419 void Sema::RefersToMemberWithReducedAlignment(
16420     Expr *E,
16421     llvm::function_ref<void(Expr *, RecordDecl *, FieldDecl *, CharUnits)>
16422         Action) {
16423   const auto *ME = dyn_cast<MemberExpr>(E);
16424   if (!ME)
16425     return;
16426 
16427   // No need to check expressions with an __unaligned-qualified type.
16428   if (E->getType().getQualifiers().hasUnaligned())
16429     return;
16430 
16431   // For a chain of MemberExpr like "a.b.c.d" this list
16432   // will keep FieldDecl's like [d, c, b].
16433   SmallVector<FieldDecl *, 4> ReverseMemberChain;
16434   const MemberExpr *TopME = nullptr;
16435   bool AnyIsPacked = false;
16436   do {
16437     QualType BaseType = ME->getBase()->getType();
16438     if (BaseType->isDependentType())
16439       return;
16440     if (ME->isArrow())
16441       BaseType = BaseType->getPointeeType();
16442     RecordDecl *RD = BaseType->castAs<RecordType>()->getDecl();
16443     if (RD->isInvalidDecl())
16444       return;
16445 
16446     ValueDecl *MD = ME->getMemberDecl();
16447     auto *FD = dyn_cast<FieldDecl>(MD);
16448     // We do not care about non-data members.
16449     if (!FD || FD->isInvalidDecl())
16450       return;
16451 
16452     AnyIsPacked =
16453         AnyIsPacked || (RD->hasAttr<PackedAttr>() || MD->hasAttr<PackedAttr>());
16454     ReverseMemberChain.push_back(FD);
16455 
16456     TopME = ME;
16457     ME = dyn_cast<MemberExpr>(ME->getBase()->IgnoreParens());
16458   } while (ME);
16459   assert(TopME && "We did not compute a topmost MemberExpr!");
16460 
16461   // Not the scope of this diagnostic.
16462   if (!AnyIsPacked)
16463     return;
16464 
16465   const Expr *TopBase = TopME->getBase()->IgnoreParenImpCasts();
16466   const auto *DRE = dyn_cast<DeclRefExpr>(TopBase);
16467   // TODO: The innermost base of the member expression may be too complicated.
16468   // For now, just disregard these cases. This is left for future
16469   // improvement.
16470   if (!DRE && !isa<CXXThisExpr>(TopBase))
16471       return;
16472 
16473   // Alignment expected by the whole expression.
16474   CharUnits ExpectedAlignment = Context.getTypeAlignInChars(E->getType());
16475 
16476   // No need to do anything else with this case.
16477   if (ExpectedAlignment.isOne())
16478     return;
16479 
16480   // Synthesize offset of the whole access.
16481   CharUnits Offset;
16482   for (auto I = ReverseMemberChain.rbegin(); I != ReverseMemberChain.rend();
16483        I++) {
16484     Offset += Context.toCharUnitsFromBits(Context.getFieldOffset(*I));
16485   }
16486 
16487   // Compute the CompleteObjectAlignment as the alignment of the whole chain.
16488   CharUnits CompleteObjectAlignment = Context.getTypeAlignInChars(
16489       ReverseMemberChain.back()->getParent()->getTypeForDecl());
16490 
16491   // The base expression of the innermost MemberExpr may give
16492   // stronger guarantees than the class containing the member.
16493   if (DRE && !TopME->isArrow()) {
16494     const ValueDecl *VD = DRE->getDecl();
16495     if (!VD->getType()->isReferenceType())
16496       CompleteObjectAlignment =
16497           std::max(CompleteObjectAlignment, Context.getDeclAlign(VD));
16498   }
16499 
16500   // Check if the synthesized offset fulfills the alignment.
16501   if (Offset % ExpectedAlignment != 0 ||
16502       // It may fulfill the offset it but the effective alignment may still be
16503       // lower than the expected expression alignment.
16504       CompleteObjectAlignment < ExpectedAlignment) {
16505     // If this happens, we want to determine a sensible culprit of this.
16506     // Intuitively, watching the chain of member expressions from right to
16507     // left, we start with the required alignment (as required by the field
16508     // type) but some packed attribute in that chain has reduced the alignment.
16509     // It may happen that another packed structure increases it again. But if
16510     // we are here such increase has not been enough. So pointing the first
16511     // FieldDecl that either is packed or else its RecordDecl is,
16512     // seems reasonable.
16513     FieldDecl *FD = nullptr;
16514     CharUnits Alignment;
16515     for (FieldDecl *FDI : ReverseMemberChain) {
16516       if (FDI->hasAttr<PackedAttr>() ||
16517           FDI->getParent()->hasAttr<PackedAttr>()) {
16518         FD = FDI;
16519         Alignment = std::min(
16520             Context.getTypeAlignInChars(FD->getType()),
16521             Context.getTypeAlignInChars(FD->getParent()->getTypeForDecl()));
16522         break;
16523       }
16524     }
16525     assert(FD && "We did not find a packed FieldDecl!");
16526     Action(E, FD->getParent(), FD, Alignment);
16527   }
16528 }
16529 
16530 void Sema::CheckAddressOfPackedMember(Expr *rhs) {
16531   using namespace std::placeholders;
16532 
16533   RefersToMemberWithReducedAlignment(
16534       rhs, std::bind(&Sema::AddPotentialMisalignedMembers, std::ref(*this), _1,
16535                      _2, _3, _4));
16536 }
16537 
16538 ExprResult Sema::SemaBuiltinMatrixTranspose(CallExpr *TheCall,
16539                                             ExprResult CallResult) {
16540   if (checkArgCount(*this, TheCall, 1))
16541     return ExprError();
16542 
16543   ExprResult MatrixArg = DefaultLvalueConversion(TheCall->getArg(0));
16544   if (MatrixArg.isInvalid())
16545     return MatrixArg;
16546   Expr *Matrix = MatrixArg.get();
16547 
16548   auto *MType = Matrix->getType()->getAs<ConstantMatrixType>();
16549   if (!MType) {
16550     Diag(Matrix->getBeginLoc(), diag::err_builtin_matrix_arg);
16551     return ExprError();
16552   }
16553 
16554   // Create returned matrix type by swapping rows and columns of the argument
16555   // matrix type.
16556   QualType ResultType = Context.getConstantMatrixType(
16557       MType->getElementType(), MType->getNumColumns(), MType->getNumRows());
16558 
16559   // Change the return type to the type of the returned matrix.
16560   TheCall->setType(ResultType);
16561 
16562   // Update call argument to use the possibly converted matrix argument.
16563   TheCall->setArg(0, Matrix);
16564   return CallResult;
16565 }
16566 
16567 // Get and verify the matrix dimensions.
16568 static llvm::Optional<unsigned>
16569 getAndVerifyMatrixDimension(Expr *Expr, StringRef Name, Sema &S) {
16570   SourceLocation ErrorPos;
16571   Optional<llvm::APSInt> Value =
16572       Expr->getIntegerConstantExpr(S.Context, &ErrorPos);
16573   if (!Value) {
16574     S.Diag(Expr->getBeginLoc(), diag::err_builtin_matrix_scalar_unsigned_arg)
16575         << Name;
16576     return {};
16577   }
16578   uint64_t Dim = Value->getZExtValue();
16579   if (!ConstantMatrixType::isDimensionValid(Dim)) {
16580     S.Diag(Expr->getBeginLoc(), diag::err_builtin_matrix_invalid_dimension)
16581         << Name << ConstantMatrixType::getMaxElementsPerDimension();
16582     return {};
16583   }
16584   return Dim;
16585 }
16586 
16587 ExprResult Sema::SemaBuiltinMatrixColumnMajorLoad(CallExpr *TheCall,
16588                                                   ExprResult CallResult) {
16589   if (!getLangOpts().MatrixTypes) {
16590     Diag(TheCall->getBeginLoc(), diag::err_builtin_matrix_disabled);
16591     return ExprError();
16592   }
16593 
16594   if (checkArgCount(*this, TheCall, 4))
16595     return ExprError();
16596 
16597   unsigned PtrArgIdx = 0;
16598   Expr *PtrExpr = TheCall->getArg(PtrArgIdx);
16599   Expr *RowsExpr = TheCall->getArg(1);
16600   Expr *ColumnsExpr = TheCall->getArg(2);
16601   Expr *StrideExpr = TheCall->getArg(3);
16602 
16603   bool ArgError = false;
16604 
16605   // Check pointer argument.
16606   {
16607     ExprResult PtrConv = DefaultFunctionArrayLvalueConversion(PtrExpr);
16608     if (PtrConv.isInvalid())
16609       return PtrConv;
16610     PtrExpr = PtrConv.get();
16611     TheCall->setArg(0, PtrExpr);
16612     if (PtrExpr->isTypeDependent()) {
16613       TheCall->setType(Context.DependentTy);
16614       return TheCall;
16615     }
16616   }
16617 
16618   auto *PtrTy = PtrExpr->getType()->getAs<PointerType>();
16619   QualType ElementTy;
16620   if (!PtrTy) {
16621     Diag(PtrExpr->getBeginLoc(), diag::err_builtin_matrix_pointer_arg)
16622         << PtrArgIdx + 1;
16623     ArgError = true;
16624   } else {
16625     ElementTy = PtrTy->getPointeeType().getUnqualifiedType();
16626 
16627     if (!ConstantMatrixType::isValidElementType(ElementTy)) {
16628       Diag(PtrExpr->getBeginLoc(), diag::err_builtin_matrix_pointer_arg)
16629           << PtrArgIdx + 1;
16630       ArgError = true;
16631     }
16632   }
16633 
16634   // Apply default Lvalue conversions and convert the expression to size_t.
16635   auto ApplyArgumentConversions = [this](Expr *E) {
16636     ExprResult Conv = DefaultLvalueConversion(E);
16637     if (Conv.isInvalid())
16638       return Conv;
16639 
16640     return tryConvertExprToType(Conv.get(), Context.getSizeType());
16641   };
16642 
16643   // Apply conversion to row and column expressions.
16644   ExprResult RowsConv = ApplyArgumentConversions(RowsExpr);
16645   if (!RowsConv.isInvalid()) {
16646     RowsExpr = RowsConv.get();
16647     TheCall->setArg(1, RowsExpr);
16648   } else
16649     RowsExpr = nullptr;
16650 
16651   ExprResult ColumnsConv = ApplyArgumentConversions(ColumnsExpr);
16652   if (!ColumnsConv.isInvalid()) {
16653     ColumnsExpr = ColumnsConv.get();
16654     TheCall->setArg(2, ColumnsExpr);
16655   } else
16656     ColumnsExpr = nullptr;
16657 
16658   // If any any part of the result matrix type is still pending, just use
16659   // Context.DependentTy, until all parts are resolved.
16660   if ((RowsExpr && RowsExpr->isTypeDependent()) ||
16661       (ColumnsExpr && ColumnsExpr->isTypeDependent())) {
16662     TheCall->setType(Context.DependentTy);
16663     return CallResult;
16664   }
16665 
16666   // Check row and column dimenions.
16667   llvm::Optional<unsigned> MaybeRows;
16668   if (RowsExpr)
16669     MaybeRows = getAndVerifyMatrixDimension(RowsExpr, "row", *this);
16670 
16671   llvm::Optional<unsigned> MaybeColumns;
16672   if (ColumnsExpr)
16673     MaybeColumns = getAndVerifyMatrixDimension(ColumnsExpr, "column", *this);
16674 
16675   // Check stride argument.
16676   ExprResult StrideConv = ApplyArgumentConversions(StrideExpr);
16677   if (StrideConv.isInvalid())
16678     return ExprError();
16679   StrideExpr = StrideConv.get();
16680   TheCall->setArg(3, StrideExpr);
16681 
16682   if (MaybeRows) {
16683     if (Optional<llvm::APSInt> Value =
16684             StrideExpr->getIntegerConstantExpr(Context)) {
16685       uint64_t Stride = Value->getZExtValue();
16686       if (Stride < *MaybeRows) {
16687         Diag(StrideExpr->getBeginLoc(),
16688              diag::err_builtin_matrix_stride_too_small);
16689         ArgError = true;
16690       }
16691     }
16692   }
16693 
16694   if (ArgError || !MaybeRows || !MaybeColumns)
16695     return ExprError();
16696 
16697   TheCall->setType(
16698       Context.getConstantMatrixType(ElementTy, *MaybeRows, *MaybeColumns));
16699   return CallResult;
16700 }
16701 
16702 ExprResult Sema::SemaBuiltinMatrixColumnMajorStore(CallExpr *TheCall,
16703                                                    ExprResult CallResult) {
16704   if (checkArgCount(*this, TheCall, 3))
16705     return ExprError();
16706 
16707   unsigned PtrArgIdx = 1;
16708   Expr *MatrixExpr = TheCall->getArg(0);
16709   Expr *PtrExpr = TheCall->getArg(PtrArgIdx);
16710   Expr *StrideExpr = TheCall->getArg(2);
16711 
16712   bool ArgError = false;
16713 
16714   {
16715     ExprResult MatrixConv = DefaultLvalueConversion(MatrixExpr);
16716     if (MatrixConv.isInvalid())
16717       return MatrixConv;
16718     MatrixExpr = MatrixConv.get();
16719     TheCall->setArg(0, MatrixExpr);
16720   }
16721   if (MatrixExpr->isTypeDependent()) {
16722     TheCall->setType(Context.DependentTy);
16723     return TheCall;
16724   }
16725 
16726   auto *MatrixTy = MatrixExpr->getType()->getAs<ConstantMatrixType>();
16727   if (!MatrixTy) {
16728     Diag(MatrixExpr->getBeginLoc(), diag::err_builtin_matrix_arg) << 0;
16729     ArgError = true;
16730   }
16731 
16732   {
16733     ExprResult PtrConv = DefaultFunctionArrayLvalueConversion(PtrExpr);
16734     if (PtrConv.isInvalid())
16735       return PtrConv;
16736     PtrExpr = PtrConv.get();
16737     TheCall->setArg(1, PtrExpr);
16738     if (PtrExpr->isTypeDependent()) {
16739       TheCall->setType(Context.DependentTy);
16740       return TheCall;
16741     }
16742   }
16743 
16744   // Check pointer argument.
16745   auto *PtrTy = PtrExpr->getType()->getAs<PointerType>();
16746   if (!PtrTy) {
16747     Diag(PtrExpr->getBeginLoc(), diag::err_builtin_matrix_pointer_arg)
16748         << PtrArgIdx + 1;
16749     ArgError = true;
16750   } else {
16751     QualType ElementTy = PtrTy->getPointeeType();
16752     if (ElementTy.isConstQualified()) {
16753       Diag(PtrExpr->getBeginLoc(), diag::err_builtin_matrix_store_to_const);
16754       ArgError = true;
16755     }
16756     ElementTy = ElementTy.getUnqualifiedType().getCanonicalType();
16757     if (MatrixTy &&
16758         !Context.hasSameType(ElementTy, MatrixTy->getElementType())) {
16759       Diag(PtrExpr->getBeginLoc(),
16760            diag::err_builtin_matrix_pointer_arg_mismatch)
16761           << ElementTy << MatrixTy->getElementType();
16762       ArgError = true;
16763     }
16764   }
16765 
16766   // Apply default Lvalue conversions and convert the stride expression to
16767   // size_t.
16768   {
16769     ExprResult StrideConv = DefaultLvalueConversion(StrideExpr);
16770     if (StrideConv.isInvalid())
16771       return StrideConv;
16772 
16773     StrideConv = tryConvertExprToType(StrideConv.get(), Context.getSizeType());
16774     if (StrideConv.isInvalid())
16775       return StrideConv;
16776     StrideExpr = StrideConv.get();
16777     TheCall->setArg(2, StrideExpr);
16778   }
16779 
16780   // Check stride argument.
16781   if (MatrixTy) {
16782     if (Optional<llvm::APSInt> Value =
16783             StrideExpr->getIntegerConstantExpr(Context)) {
16784       uint64_t Stride = Value->getZExtValue();
16785       if (Stride < MatrixTy->getNumRows()) {
16786         Diag(StrideExpr->getBeginLoc(),
16787              diag::err_builtin_matrix_stride_too_small);
16788         ArgError = true;
16789       }
16790     }
16791   }
16792 
16793   if (ArgError)
16794     return ExprError();
16795 
16796   return CallResult;
16797 }
16798 
16799 /// \brief Enforce the bounds of a TCB
16800 /// CheckTCBEnforcement - Enforces that every function in a named TCB only
16801 /// directly calls other functions in the same TCB as marked by the enforce_tcb
16802 /// and enforce_tcb_leaf attributes.
16803 void Sema::CheckTCBEnforcement(const CallExpr *TheCall,
16804                                const FunctionDecl *Callee) {
16805   const FunctionDecl *Caller = getCurFunctionDecl();
16806 
16807   // Calls to builtins are not enforced.
16808   if (!Caller || !Caller->hasAttr<EnforceTCBAttr>() ||
16809       Callee->getBuiltinID() != 0)
16810     return;
16811 
16812   // Search through the enforce_tcb and enforce_tcb_leaf attributes to find
16813   // all TCBs the callee is a part of.
16814   llvm::StringSet<> CalleeTCBs;
16815   for_each(Callee->specific_attrs<EnforceTCBAttr>(),
16816            [&](const auto *A) { CalleeTCBs.insert(A->getTCBName()); });
16817   for_each(Callee->specific_attrs<EnforceTCBLeafAttr>(),
16818            [&](const auto *A) { CalleeTCBs.insert(A->getTCBName()); });
16819 
16820   // Go through the TCBs the caller is a part of and emit warnings if Caller
16821   // is in a TCB that the Callee is not.
16822   for_each(
16823       Caller->specific_attrs<EnforceTCBAttr>(),
16824       [&](const auto *A) {
16825         StringRef CallerTCB = A->getTCBName();
16826         if (CalleeTCBs.count(CallerTCB) == 0) {
16827           this->Diag(TheCall->getExprLoc(),
16828                      diag::warn_tcb_enforcement_violation) << Callee
16829                                                            << CallerTCB;
16830         }
16831       });
16832 }
16833