1 //===-- CodeGenFunction.h - Per-Function state for LLVM CodeGen -*- C++ -*-===//
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 is the internal per-function state used for llvm translation.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_LIB_CODEGEN_CODEGENFUNCTION_H
14 #define LLVM_CLANG_LIB_CODEGEN_CODEGENFUNCTION_H
15 
16 #include "CGBuilder.h"
17 #include "CGDebugInfo.h"
18 #include "CGLoopInfo.h"
19 #include "CGValue.h"
20 #include "CodeGenModule.h"
21 #include "CodeGenPGO.h"
22 #include "EHScopeStack.h"
23 #include "VarBypassDetector.h"
24 #include "clang/AST/CharUnits.h"
25 #include "clang/AST/CurrentSourceLocExprScope.h"
26 #include "clang/AST/ExprCXX.h"
27 #include "clang/AST/ExprObjC.h"
28 #include "clang/AST/ExprOpenMP.h"
29 #include "clang/AST/StmtOpenMP.h"
30 #include "clang/AST/Type.h"
31 #include "clang/Basic/ABI.h"
32 #include "clang/Basic/CapturedStmt.h"
33 #include "clang/Basic/CodeGenOptions.h"
34 #include "clang/Basic/OpenMPKinds.h"
35 #include "clang/Basic/TargetInfo.h"
36 #include "llvm/ADT/ArrayRef.h"
37 #include "llvm/ADT/DenseMap.h"
38 #include "llvm/ADT/MapVector.h"
39 #include "llvm/ADT/SmallVector.h"
40 #include "llvm/Frontend/OpenMP/OMPIRBuilder.h"
41 #include "llvm/IR/ValueHandle.h"
42 #include "llvm/Support/Debug.h"
43 #include "llvm/Transforms/Utils/SanitizerStats.h"
44 
45 namespace llvm {
46 class BasicBlock;
47 class LLVMContext;
48 class MDNode;
49 class Module;
50 class SwitchInst;
51 class Twine;
52 class Value;
53 class CanonicalLoopInfo;
54 }
55 
56 namespace clang {
57 class ASTContext;
58 class BlockDecl;
59 class CXXDestructorDecl;
60 class CXXForRangeStmt;
61 class CXXTryStmt;
62 class Decl;
63 class LabelDecl;
64 class EnumConstantDecl;
65 class FunctionDecl;
66 class FunctionProtoType;
67 class LabelStmt;
68 class ObjCContainerDecl;
69 class ObjCInterfaceDecl;
70 class ObjCIvarDecl;
71 class ObjCMethodDecl;
72 class ObjCImplementationDecl;
73 class ObjCPropertyImplDecl;
74 class TargetInfo;
75 class VarDecl;
76 class ObjCForCollectionStmt;
77 class ObjCAtTryStmt;
78 class ObjCAtThrowStmt;
79 class ObjCAtSynchronizedStmt;
80 class ObjCAutoreleasePoolStmt;
81 class OMPUseDevicePtrClause;
82 class OMPUseDeviceAddrClause;
83 class ReturnsNonNullAttr;
84 class SVETypeFlags;
85 class OMPExecutableDirective;
86 
87 namespace analyze_os_log {
88 class OSLogBufferLayout;
89 }
90 
91 namespace CodeGen {
92 class CodeGenTypes;
93 class CGCallee;
94 class CGFunctionInfo;
95 class CGRecordLayout;
96 class CGBlockInfo;
97 class CGCXXABI;
98 class BlockByrefHelpers;
99 class BlockByrefInfo;
100 class BlockFlags;
101 class BlockFieldFlags;
102 class RegionCodeGenTy;
103 class TargetCodeGenInfo;
104 struct OMPTaskDataTy;
105 struct CGCoroData;
106 
107 /// The kind of evaluation to perform on values of a particular
108 /// type.  Basically, is the code in CGExprScalar, CGExprComplex, or
109 /// CGExprAgg?
110 ///
111 /// TODO: should vectors maybe be split out into their own thing?
112 enum TypeEvaluationKind {
113   TEK_Scalar,
114   TEK_Complex,
115   TEK_Aggregate
116 };
117 
118 #define LIST_SANITIZER_CHECKS                                                  \
119   SANITIZER_CHECK(AddOverflow, add_overflow, 0)                                \
120   SANITIZER_CHECK(BuiltinUnreachable, builtin_unreachable, 0)                  \
121   SANITIZER_CHECK(CFICheckFail, cfi_check_fail, 0)                             \
122   SANITIZER_CHECK(DivremOverflow, divrem_overflow, 0)                          \
123   SANITIZER_CHECK(DynamicTypeCacheMiss, dynamic_type_cache_miss, 0)            \
124   SANITIZER_CHECK(FloatCastOverflow, float_cast_overflow, 0)                   \
125   SANITIZER_CHECK(FunctionTypeMismatch, function_type_mismatch, 1)             \
126   SANITIZER_CHECK(ImplicitConversion, implicit_conversion, 0)                  \
127   SANITIZER_CHECK(InvalidBuiltin, invalid_builtin, 0)                          \
128   SANITIZER_CHECK(InvalidObjCCast, invalid_objc_cast, 0)                       \
129   SANITIZER_CHECK(LoadInvalidValue, load_invalid_value, 0)                     \
130   SANITIZER_CHECK(MissingReturn, missing_return, 0)                            \
131   SANITIZER_CHECK(MulOverflow, mul_overflow, 0)                                \
132   SANITIZER_CHECK(NegateOverflow, negate_overflow, 0)                          \
133   SANITIZER_CHECK(NullabilityArg, nullability_arg, 0)                          \
134   SANITIZER_CHECK(NullabilityReturn, nullability_return, 1)                    \
135   SANITIZER_CHECK(NonnullArg, nonnull_arg, 0)                                  \
136   SANITIZER_CHECK(NonnullReturn, nonnull_return, 1)                            \
137   SANITIZER_CHECK(OutOfBounds, out_of_bounds, 0)                               \
138   SANITIZER_CHECK(PointerOverflow, pointer_overflow, 0)                        \
139   SANITIZER_CHECK(ShiftOutOfBounds, shift_out_of_bounds, 0)                    \
140   SANITIZER_CHECK(SubOverflow, sub_overflow, 0)                                \
141   SANITIZER_CHECK(TypeMismatch, type_mismatch, 1)                              \
142   SANITIZER_CHECK(AlignmentAssumption, alignment_assumption, 0)                \
143   SANITIZER_CHECK(VLABoundNotPositive, vla_bound_not_positive, 0)
144 
145 enum SanitizerHandler {
146 #define SANITIZER_CHECK(Enum, Name, Version) Enum,
147   LIST_SANITIZER_CHECKS
148 #undef SANITIZER_CHECK
149 };
150 
151 /// Helper class with most of the code for saving a value for a
152 /// conditional expression cleanup.
153 struct DominatingLLVMValue {
154   typedef llvm::PointerIntPair<llvm::Value*, 1, bool> saved_type;
155 
156   /// Answer whether the given value needs extra work to be saved.
157   static bool needsSaving(llvm::Value *value) {
158     // If it's not an instruction, we don't need to save.
159     if (!isa<llvm::Instruction>(value)) return false;
160 
161     // If it's an instruction in the entry block, we don't need to save.
162     llvm::BasicBlock *block = cast<llvm::Instruction>(value)->getParent();
163     return (block != &block->getParent()->getEntryBlock());
164   }
165 
166   static saved_type save(CodeGenFunction &CGF, llvm::Value *value);
167   static llvm::Value *restore(CodeGenFunction &CGF, saved_type value);
168 };
169 
170 /// A partial specialization of DominatingValue for llvm::Values that
171 /// might be llvm::Instructions.
172 template <class T> struct DominatingPointer<T,true> : DominatingLLVMValue {
173   typedef T *type;
174   static type restore(CodeGenFunction &CGF, saved_type value) {
175     return static_cast<T*>(DominatingLLVMValue::restore(CGF, value));
176   }
177 };
178 
179 /// A specialization of DominatingValue for Address.
180 template <> struct DominatingValue<Address> {
181   typedef Address type;
182 
183   struct saved_type {
184     DominatingLLVMValue::saved_type SavedValue;
185     CharUnits Alignment;
186   };
187 
188   static bool needsSaving(type value) {
189     return DominatingLLVMValue::needsSaving(value.getPointer());
190   }
191   static saved_type save(CodeGenFunction &CGF, type value) {
192     return { DominatingLLVMValue::save(CGF, value.getPointer()),
193              value.getAlignment() };
194   }
195   static type restore(CodeGenFunction &CGF, saved_type value) {
196     return Address(DominatingLLVMValue::restore(CGF, value.SavedValue),
197                    value.Alignment);
198   }
199 };
200 
201 /// A specialization of DominatingValue for RValue.
202 template <> struct DominatingValue<RValue> {
203   typedef RValue type;
204   class saved_type {
205     enum Kind { ScalarLiteral, ScalarAddress, AggregateLiteral,
206                 AggregateAddress, ComplexAddress };
207 
208     llvm::Value *Value;
209     unsigned K : 3;
210     unsigned Align : 29;
211     saved_type(llvm::Value *v, Kind k, unsigned a = 0)
212       : Value(v), K(k), Align(a) {}
213 
214   public:
215     static bool needsSaving(RValue value);
216     static saved_type save(CodeGenFunction &CGF, RValue value);
217     RValue restore(CodeGenFunction &CGF);
218 
219     // implementations in CGCleanup.cpp
220   };
221 
222   static bool needsSaving(type value) {
223     return saved_type::needsSaving(value);
224   }
225   static saved_type save(CodeGenFunction &CGF, type value) {
226     return saved_type::save(CGF, value);
227   }
228   static type restore(CodeGenFunction &CGF, saved_type value) {
229     return value.restore(CGF);
230   }
231 };
232 
233 /// CodeGenFunction - This class organizes the per-function state that is used
234 /// while generating LLVM code.
235 class CodeGenFunction : public CodeGenTypeCache {
236   CodeGenFunction(const CodeGenFunction &) = delete;
237   void operator=(const CodeGenFunction &) = delete;
238 
239   friend class CGCXXABI;
240 public:
241   /// A jump destination is an abstract label, branching to which may
242   /// require a jump out through normal cleanups.
243   struct JumpDest {
244     JumpDest() : Block(nullptr), ScopeDepth(), Index(0) {}
245     JumpDest(llvm::BasicBlock *Block,
246              EHScopeStack::stable_iterator Depth,
247              unsigned Index)
248       : Block(Block), ScopeDepth(Depth), Index(Index) {}
249 
250     bool isValid() const { return Block != nullptr; }
251     llvm::BasicBlock *getBlock() const { return Block; }
252     EHScopeStack::stable_iterator getScopeDepth() const { return ScopeDepth; }
253     unsigned getDestIndex() const { return Index; }
254 
255     // This should be used cautiously.
256     void setScopeDepth(EHScopeStack::stable_iterator depth) {
257       ScopeDepth = depth;
258     }
259 
260   private:
261     llvm::BasicBlock *Block;
262     EHScopeStack::stable_iterator ScopeDepth;
263     unsigned Index;
264   };
265 
266   CodeGenModule &CGM;  // Per-module state.
267   const TargetInfo &Target;
268 
269   // For EH/SEH outlined funclets, this field points to parent's CGF
270   CodeGenFunction *ParentCGF = nullptr;
271 
272   typedef std::pair<llvm::Value *, llvm::Value *> ComplexPairTy;
273   LoopInfoStack LoopStack;
274   CGBuilderTy Builder;
275 
276   // Stores variables for which we can't generate correct lifetime markers
277   // because of jumps.
278   VarBypassDetector Bypasses;
279 
280   /// List of recently emitted OMPCanonicalLoops.
281   ///
282   /// Since OMPCanonicalLoops are nested inside other statements (in particular
283   /// CapturedStmt generated by OMPExecutableDirective and non-perfectly nested
284   /// loops), we cannot directly call OMPEmitOMPCanonicalLoop and receive its
285   /// llvm::CanonicalLoopInfo. Instead, we call EmitStmt and any
286   /// OMPEmitOMPCanonicalLoop called by it will add its CanonicalLoopInfo to
287   /// this stack when done. Entering a new loop requires clearing this list; it
288   /// either means we start parsing a new loop nest (in which case the previous
289   /// loop nest goes out of scope) or a second loop in the same level in which
290   /// case it would be ambiguous into which of the two (or more) loops the loop
291   /// nest would extend.
292   SmallVector<llvm::CanonicalLoopInfo *, 4> OMPLoopNestStack;
293 
294   // CodeGen lambda for loops and support for ordered clause
295   typedef llvm::function_ref<void(CodeGenFunction &, const OMPLoopDirective &,
296                                   JumpDest)>
297       CodeGenLoopTy;
298   typedef llvm::function_ref<void(CodeGenFunction &, SourceLocation,
299                                   const unsigned, const bool)>
300       CodeGenOrderedTy;
301 
302   // Codegen lambda for loop bounds in worksharing loop constructs
303   typedef llvm::function_ref<std::pair<LValue, LValue>(
304       CodeGenFunction &, const OMPExecutableDirective &S)>
305       CodeGenLoopBoundsTy;
306 
307   // Codegen lambda for loop bounds in dispatch-based loop implementation
308   typedef llvm::function_ref<std::pair<llvm::Value *, llvm::Value *>(
309       CodeGenFunction &, const OMPExecutableDirective &S, Address LB,
310       Address UB)>
311       CodeGenDispatchBoundsTy;
312 
313   /// CGBuilder insert helper. This function is called after an
314   /// instruction is created using Builder.
315   void InsertHelper(llvm::Instruction *I, const llvm::Twine &Name,
316                     llvm::BasicBlock *BB,
317                     llvm::BasicBlock::iterator InsertPt) const;
318 
319   /// CurFuncDecl - Holds the Decl for the current outermost
320   /// non-closure context.
321   const Decl *CurFuncDecl;
322   /// CurCodeDecl - This is the inner-most code context, which includes blocks.
323   const Decl *CurCodeDecl;
324   const CGFunctionInfo *CurFnInfo;
325   QualType FnRetTy;
326   llvm::Function *CurFn = nullptr;
327 
328   /// Save Parameter Decl for coroutine.
329   llvm::SmallVector<const ParmVarDecl *, 4> FnArgs;
330 
331   // Holds coroutine data if the current function is a coroutine. We use a
332   // wrapper to manage its lifetime, so that we don't have to define CGCoroData
333   // in this header.
334   struct CGCoroInfo {
335     std::unique_ptr<CGCoroData> Data;
336     CGCoroInfo();
337     ~CGCoroInfo();
338   };
339   CGCoroInfo CurCoro;
340 
341   bool isCoroutine() const {
342     return CurCoro.Data != nullptr;
343   }
344 
345   /// CurGD - The GlobalDecl for the current function being compiled.
346   GlobalDecl CurGD;
347 
348   /// PrologueCleanupDepth - The cleanup depth enclosing all the
349   /// cleanups associated with the parameters.
350   EHScopeStack::stable_iterator PrologueCleanupDepth;
351 
352   /// ReturnBlock - Unified return block.
353   JumpDest ReturnBlock;
354 
355   /// ReturnValue - The temporary alloca to hold the return
356   /// value. This is invalid iff the function has no return value.
357   Address ReturnValue = Address::invalid();
358 
359   /// ReturnValuePointer - The temporary alloca to hold a pointer to sret.
360   /// This is invalid if sret is not in use.
361   Address ReturnValuePointer = Address::invalid();
362 
363   /// If a return statement is being visited, this holds the return statment's
364   /// result expression.
365   const Expr *RetExpr = nullptr;
366 
367   /// Return true if a label was seen in the current scope.
368   bool hasLabelBeenSeenInCurrentScope() const {
369     if (CurLexicalScope)
370       return CurLexicalScope->hasLabels();
371     return !LabelMap.empty();
372   }
373 
374   /// AllocaInsertPoint - This is an instruction in the entry block before which
375   /// we prefer to insert allocas.
376   llvm::AssertingVH<llvm::Instruction> AllocaInsertPt;
377 
378   /// API for captured statement code generation.
379   class CGCapturedStmtInfo {
380   public:
381     explicit CGCapturedStmtInfo(CapturedRegionKind K = CR_Default)
382         : Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {}
383     explicit CGCapturedStmtInfo(const CapturedStmt &S,
384                                 CapturedRegionKind K = CR_Default)
385       : Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {
386 
387       RecordDecl::field_iterator Field =
388         S.getCapturedRecordDecl()->field_begin();
389       for (CapturedStmt::const_capture_iterator I = S.capture_begin(),
390                                                 E = S.capture_end();
391            I != E; ++I, ++Field) {
392         if (I->capturesThis())
393           CXXThisFieldDecl = *Field;
394         else if (I->capturesVariable())
395           CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
396         else if (I->capturesVariableByCopy())
397           CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
398       }
399     }
400 
401     virtual ~CGCapturedStmtInfo();
402 
403     CapturedRegionKind getKind() const { return Kind; }
404 
405     virtual void setContextValue(llvm::Value *V) { ThisValue = V; }
406     // Retrieve the value of the context parameter.
407     virtual llvm::Value *getContextValue() const { return ThisValue; }
408 
409     /// Lookup the captured field decl for a variable.
410     virtual const FieldDecl *lookup(const VarDecl *VD) const {
411       return CaptureFields.lookup(VD->getCanonicalDecl());
412     }
413 
414     bool isCXXThisExprCaptured() const { return getThisFieldDecl() != nullptr; }
415     virtual FieldDecl *getThisFieldDecl() const { return CXXThisFieldDecl; }
416 
417     static bool classof(const CGCapturedStmtInfo *) {
418       return true;
419     }
420 
421     /// Emit the captured statement body.
422     virtual void EmitBody(CodeGenFunction &CGF, const Stmt *S) {
423       CGF.incrementProfileCounter(S);
424       CGF.EmitStmt(S);
425     }
426 
427     /// Get the name of the capture helper.
428     virtual StringRef getHelperName() const { return "__captured_stmt"; }
429 
430   private:
431     /// The kind of captured statement being generated.
432     CapturedRegionKind Kind;
433 
434     /// Keep the map between VarDecl and FieldDecl.
435     llvm::SmallDenseMap<const VarDecl *, FieldDecl *> CaptureFields;
436 
437     /// The base address of the captured record, passed in as the first
438     /// argument of the parallel region function.
439     llvm::Value *ThisValue;
440 
441     /// Captured 'this' type.
442     FieldDecl *CXXThisFieldDecl;
443   };
444   CGCapturedStmtInfo *CapturedStmtInfo = nullptr;
445 
446   /// RAII for correct setting/restoring of CapturedStmtInfo.
447   class CGCapturedStmtRAII {
448   private:
449     CodeGenFunction &CGF;
450     CGCapturedStmtInfo *PrevCapturedStmtInfo;
451   public:
452     CGCapturedStmtRAII(CodeGenFunction &CGF,
453                        CGCapturedStmtInfo *NewCapturedStmtInfo)
454         : CGF(CGF), PrevCapturedStmtInfo(CGF.CapturedStmtInfo) {
455       CGF.CapturedStmtInfo = NewCapturedStmtInfo;
456     }
457     ~CGCapturedStmtRAII() { CGF.CapturedStmtInfo = PrevCapturedStmtInfo; }
458   };
459 
460   /// An abstract representation of regular/ObjC call/message targets.
461   class AbstractCallee {
462     /// The function declaration of the callee.
463     const Decl *CalleeDecl;
464 
465   public:
466     AbstractCallee() : CalleeDecl(nullptr) {}
467     AbstractCallee(const FunctionDecl *FD) : CalleeDecl(FD) {}
468     AbstractCallee(const ObjCMethodDecl *OMD) : CalleeDecl(OMD) {}
469     bool hasFunctionDecl() const {
470       return dyn_cast_or_null<FunctionDecl>(CalleeDecl);
471     }
472     const Decl *getDecl() const { return CalleeDecl; }
473     unsigned getNumParams() const {
474       if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
475         return FD->getNumParams();
476       return cast<ObjCMethodDecl>(CalleeDecl)->param_size();
477     }
478     const ParmVarDecl *getParamDecl(unsigned I) const {
479       if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
480         return FD->getParamDecl(I);
481       return *(cast<ObjCMethodDecl>(CalleeDecl)->param_begin() + I);
482     }
483   };
484 
485   /// Sanitizers enabled for this function.
486   SanitizerSet SanOpts;
487 
488   /// True if CodeGen currently emits code implementing sanitizer checks.
489   bool IsSanitizerScope = false;
490 
491   /// RAII object to set/unset CodeGenFunction::IsSanitizerScope.
492   class SanitizerScope {
493     CodeGenFunction *CGF;
494   public:
495     SanitizerScope(CodeGenFunction *CGF);
496     ~SanitizerScope();
497   };
498 
499   /// In C++, whether we are code generating a thunk.  This controls whether we
500   /// should emit cleanups.
501   bool CurFuncIsThunk = false;
502 
503   /// In ARC, whether we should autorelease the return value.
504   bool AutoreleaseResult = false;
505 
506   /// Whether we processed a Microsoft-style asm block during CodeGen. These can
507   /// potentially set the return value.
508   bool SawAsmBlock = false;
509 
510   const NamedDecl *CurSEHParent = nullptr;
511 
512   /// True if the current function is an outlined SEH helper. This can be a
513   /// finally block or filter expression.
514   bool IsOutlinedSEHHelper = false;
515 
516   /// True if CodeGen currently emits code inside presereved access index
517   /// region.
518   bool IsInPreservedAIRegion = false;
519 
520   /// True if the current statement has nomerge attribute.
521   bool InNoMergeAttributedStmt = false;
522 
523   // The CallExpr within the current statement that the musttail attribute
524   // applies to.  nullptr if there is no 'musttail' on the current statement.
525   const CallExpr *MustTailCall = nullptr;
526 
527   /// Returns true if a function must make progress, which means the
528   /// mustprogress attribute can be added.
529   bool checkIfFunctionMustProgress() {
530     if (CGM.getCodeGenOpts().getFiniteLoops() ==
531         CodeGenOptions::FiniteLoopsKind::Never)
532       return false;
533 
534     // C++11 and later guarantees that a thread eventually will do one of the
535     // following (6.9.2.3.1 in C++11):
536     // - terminate,
537     //  - make a call to a library I/O function,
538     //  - perform an access through a volatile glvalue, or
539     //  - perform a synchronization operation or an atomic operation.
540     //
541     // Hence each function is 'mustprogress' in C++11 or later.
542     return getLangOpts().CPlusPlus11;
543   }
544 
545   /// Returns true if a loop must make progress, which means the mustprogress
546   /// attribute can be added. \p HasConstantCond indicates whether the branch
547   /// condition is a known constant.
548   bool checkIfLoopMustProgress(bool HasConstantCond) {
549     if (CGM.getCodeGenOpts().getFiniteLoops() ==
550         CodeGenOptions::FiniteLoopsKind::Always)
551       return true;
552     if (CGM.getCodeGenOpts().getFiniteLoops() ==
553         CodeGenOptions::FiniteLoopsKind::Never)
554       return false;
555 
556     // If the containing function must make progress, loops also must make
557     // progress (as in C++11 and later).
558     if (checkIfFunctionMustProgress())
559       return true;
560 
561     // Now apply rules for plain C (see  6.8.5.6 in C11).
562     // Loops with constant conditions do not have to make progress in any C
563     // version.
564     if (HasConstantCond)
565       return false;
566 
567     // Loops with non-constant conditions must make progress in C11 and later.
568     return getLangOpts().C11;
569   }
570 
571   const CodeGen::CGBlockInfo *BlockInfo = nullptr;
572   llvm::Value *BlockPointer = nullptr;
573 
574   llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields;
575   FieldDecl *LambdaThisCaptureField = nullptr;
576 
577   /// A mapping from NRVO variables to the flags used to indicate
578   /// when the NRVO has been applied to this variable.
579   llvm::DenseMap<const VarDecl *, llvm::Value *> NRVOFlags;
580 
581   EHScopeStack EHStack;
582   llvm::SmallVector<char, 256> LifetimeExtendedCleanupStack;
583   llvm::SmallVector<const JumpDest *, 2> SEHTryEpilogueStack;
584 
585   llvm::Instruction *CurrentFuncletPad = nullptr;
586 
587   class CallLifetimeEnd final : public EHScopeStack::Cleanup {
588     bool isRedundantBeforeReturn() override { return true; }
589 
590     llvm::Value *Addr;
591     llvm::Value *Size;
592 
593   public:
594     CallLifetimeEnd(Address addr, llvm::Value *size)
595         : Addr(addr.getPointer()), Size(size) {}
596 
597     void Emit(CodeGenFunction &CGF, Flags flags) override {
598       CGF.EmitLifetimeEnd(Size, Addr);
599     }
600   };
601 
602   /// Header for data within LifetimeExtendedCleanupStack.
603   struct LifetimeExtendedCleanupHeader {
604     /// The size of the following cleanup object.
605     unsigned Size;
606     /// The kind of cleanup to push: a value from the CleanupKind enumeration.
607     unsigned Kind : 31;
608     /// Whether this is a conditional cleanup.
609     unsigned IsConditional : 1;
610 
611     size_t getSize() const { return Size; }
612     CleanupKind getKind() const { return (CleanupKind)Kind; }
613     bool isConditional() const { return IsConditional; }
614   };
615 
616   /// i32s containing the indexes of the cleanup destinations.
617   Address NormalCleanupDest = Address::invalid();
618 
619   unsigned NextCleanupDestIndex = 1;
620 
621   /// EHResumeBlock - Unified block containing a call to llvm.eh.resume.
622   llvm::BasicBlock *EHResumeBlock = nullptr;
623 
624   /// The exception slot.  All landing pads write the current exception pointer
625   /// into this alloca.
626   llvm::Value *ExceptionSlot = nullptr;
627 
628   /// The selector slot.  Under the MandatoryCleanup model, all landing pads
629   /// write the current selector value into this alloca.
630   llvm::AllocaInst *EHSelectorSlot = nullptr;
631 
632   /// A stack of exception code slots. Entering an __except block pushes a slot
633   /// on the stack and leaving pops one. The __exception_code() intrinsic loads
634   /// a value from the top of the stack.
635   SmallVector<Address, 1> SEHCodeSlotStack;
636 
637   /// Value returned by __exception_info intrinsic.
638   llvm::Value *SEHInfo = nullptr;
639 
640   /// Emits a landing pad for the current EH stack.
641   llvm::BasicBlock *EmitLandingPad();
642 
643   llvm::BasicBlock *getInvokeDestImpl();
644 
645   /// Parent loop-based directive for scan directive.
646   const OMPExecutableDirective *OMPParentLoopDirectiveForScan = nullptr;
647   llvm::BasicBlock *OMPBeforeScanBlock = nullptr;
648   llvm::BasicBlock *OMPAfterScanBlock = nullptr;
649   llvm::BasicBlock *OMPScanExitBlock = nullptr;
650   llvm::BasicBlock *OMPScanDispatch = nullptr;
651   bool OMPFirstScanLoop = false;
652 
653   /// Manages parent directive for scan directives.
654   class ParentLoopDirectiveForScanRegion {
655     CodeGenFunction &CGF;
656     const OMPExecutableDirective *ParentLoopDirectiveForScan;
657 
658   public:
659     ParentLoopDirectiveForScanRegion(
660         CodeGenFunction &CGF,
661         const OMPExecutableDirective &ParentLoopDirectiveForScan)
662         : CGF(CGF),
663           ParentLoopDirectiveForScan(CGF.OMPParentLoopDirectiveForScan) {
664       CGF.OMPParentLoopDirectiveForScan = &ParentLoopDirectiveForScan;
665     }
666     ~ParentLoopDirectiveForScanRegion() {
667       CGF.OMPParentLoopDirectiveForScan = ParentLoopDirectiveForScan;
668     }
669   };
670 
671   template <class T>
672   typename DominatingValue<T>::saved_type saveValueInCond(T value) {
673     return DominatingValue<T>::save(*this, value);
674   }
675 
676   class CGFPOptionsRAII {
677   public:
678     CGFPOptionsRAII(CodeGenFunction &CGF, FPOptions FPFeatures);
679     CGFPOptionsRAII(CodeGenFunction &CGF, const Expr *E);
680     ~CGFPOptionsRAII();
681 
682   private:
683     void ConstructorHelper(FPOptions FPFeatures);
684     CodeGenFunction &CGF;
685     FPOptions OldFPFeatures;
686     llvm::fp::ExceptionBehavior OldExcept;
687     llvm::RoundingMode OldRounding;
688     Optional<CGBuilderTy::FastMathFlagGuard> FMFGuard;
689   };
690   FPOptions CurFPFeatures;
691 
692 public:
693   /// ObjCEHValueStack - Stack of Objective-C exception values, used for
694   /// rethrows.
695   SmallVector<llvm::Value*, 8> ObjCEHValueStack;
696 
697   /// A class controlling the emission of a finally block.
698   class FinallyInfo {
699     /// Where the catchall's edge through the cleanup should go.
700     JumpDest RethrowDest;
701 
702     /// A function to call to enter the catch.
703     llvm::FunctionCallee BeginCatchFn;
704 
705     /// An i1 variable indicating whether or not the @finally is
706     /// running for an exception.
707     llvm::AllocaInst *ForEHVar;
708 
709     /// An i8* variable into which the exception pointer to rethrow
710     /// has been saved.
711     llvm::AllocaInst *SavedExnVar;
712 
713   public:
714     void enter(CodeGenFunction &CGF, const Stmt *Finally,
715                llvm::FunctionCallee beginCatchFn,
716                llvm::FunctionCallee endCatchFn, llvm::FunctionCallee rethrowFn);
717     void exit(CodeGenFunction &CGF);
718   };
719 
720   /// Returns true inside SEH __try blocks.
721   bool isSEHTryScope() const { return !SEHTryEpilogueStack.empty(); }
722 
723   /// Returns true while emitting a cleanuppad.
724   bool isCleanupPadScope() const {
725     return CurrentFuncletPad && isa<llvm::CleanupPadInst>(CurrentFuncletPad);
726   }
727 
728   /// pushFullExprCleanup - Push a cleanup to be run at the end of the
729   /// current full-expression.  Safe against the possibility that
730   /// we're currently inside a conditionally-evaluated expression.
731   template <class T, class... As>
732   void pushFullExprCleanup(CleanupKind kind, As... A) {
733     // If we're not in a conditional branch, or if none of the
734     // arguments requires saving, then use the unconditional cleanup.
735     if (!isInConditionalBranch())
736       return EHStack.pushCleanup<T>(kind, A...);
737 
738     // Stash values in a tuple so we can guarantee the order of saves.
739     typedef std::tuple<typename DominatingValue<As>::saved_type...> SavedTuple;
740     SavedTuple Saved{saveValueInCond(A)...};
741 
742     typedef EHScopeStack::ConditionalCleanup<T, As...> CleanupType;
743     EHStack.pushCleanupTuple<CleanupType>(kind, Saved);
744     initFullExprCleanup();
745   }
746 
747   /// Queue a cleanup to be pushed after finishing the current full-expression,
748   /// potentially with an active flag.
749   template <class T, class... As>
750   void pushCleanupAfterFullExpr(CleanupKind Kind, As... A) {
751     if (!isInConditionalBranch())
752       return pushCleanupAfterFullExprWithActiveFlag<T>(Kind, Address::invalid(),
753                                                        A...);
754 
755     Address ActiveFlag = createCleanupActiveFlag();
756     assert(!DominatingValue<Address>::needsSaving(ActiveFlag) &&
757            "cleanup active flag should never need saving");
758 
759     typedef std::tuple<typename DominatingValue<As>::saved_type...> SavedTuple;
760     SavedTuple Saved{saveValueInCond(A)...};
761 
762     typedef EHScopeStack::ConditionalCleanup<T, As...> CleanupType;
763     pushCleanupAfterFullExprWithActiveFlag<CleanupType>(Kind, ActiveFlag, Saved);
764   }
765 
766   template <class T, class... As>
767   void pushCleanupAfterFullExprWithActiveFlag(CleanupKind Kind,
768                                               Address ActiveFlag, As... A) {
769     LifetimeExtendedCleanupHeader Header = {sizeof(T), Kind,
770                                             ActiveFlag.isValid()};
771 
772     size_t OldSize = LifetimeExtendedCleanupStack.size();
773     LifetimeExtendedCleanupStack.resize(
774         LifetimeExtendedCleanupStack.size() + sizeof(Header) + Header.Size +
775         (Header.IsConditional ? sizeof(ActiveFlag) : 0));
776 
777     static_assert(sizeof(Header) % alignof(T) == 0,
778                   "Cleanup will be allocated on misaligned address");
779     char *Buffer = &LifetimeExtendedCleanupStack[OldSize];
780     new (Buffer) LifetimeExtendedCleanupHeader(Header);
781     new (Buffer + sizeof(Header)) T(A...);
782     if (Header.IsConditional)
783       new (Buffer + sizeof(Header) + sizeof(T)) Address(ActiveFlag);
784   }
785 
786   /// Set up the last cleanup that was pushed as a conditional
787   /// full-expression cleanup.
788   void initFullExprCleanup() {
789     initFullExprCleanupWithFlag(createCleanupActiveFlag());
790   }
791 
792   void initFullExprCleanupWithFlag(Address ActiveFlag);
793   Address createCleanupActiveFlag();
794 
795   /// PushDestructorCleanup - Push a cleanup to call the
796   /// complete-object destructor of an object of the given type at the
797   /// given address.  Does nothing if T is not a C++ class type with a
798   /// non-trivial destructor.
799   void PushDestructorCleanup(QualType T, Address Addr);
800 
801   /// PushDestructorCleanup - Push a cleanup to call the
802   /// complete-object variant of the given destructor on the object at
803   /// the given address.
804   void PushDestructorCleanup(const CXXDestructorDecl *Dtor, QualType T,
805                              Address Addr);
806 
807   /// PopCleanupBlock - Will pop the cleanup entry on the stack and
808   /// process all branch fixups.
809   void PopCleanupBlock(bool FallThroughIsBranchThrough = false);
810 
811   /// DeactivateCleanupBlock - Deactivates the given cleanup block.
812   /// The block cannot be reactivated.  Pops it if it's the top of the
813   /// stack.
814   ///
815   /// \param DominatingIP - An instruction which is known to
816   ///   dominate the current IP (if set) and which lies along
817   ///   all paths of execution between the current IP and the
818   ///   the point at which the cleanup comes into scope.
819   void DeactivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
820                               llvm::Instruction *DominatingIP);
821 
822   /// ActivateCleanupBlock - Activates an initially-inactive cleanup.
823   /// Cannot be used to resurrect a deactivated cleanup.
824   ///
825   /// \param DominatingIP - An instruction which is known to
826   ///   dominate the current IP (if set) and which lies along
827   ///   all paths of execution between the current IP and the
828   ///   the point at which the cleanup comes into scope.
829   void ActivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
830                             llvm::Instruction *DominatingIP);
831 
832   /// Enters a new scope for capturing cleanups, all of which
833   /// will be executed once the scope is exited.
834   class RunCleanupsScope {
835     EHScopeStack::stable_iterator CleanupStackDepth, OldCleanupScopeDepth;
836     size_t LifetimeExtendedCleanupStackSize;
837     bool OldDidCallStackSave;
838   protected:
839     bool PerformCleanup;
840   private:
841 
842     RunCleanupsScope(const RunCleanupsScope &) = delete;
843     void operator=(const RunCleanupsScope &) = delete;
844 
845   protected:
846     CodeGenFunction& CGF;
847 
848   public:
849     /// Enter a new cleanup scope.
850     explicit RunCleanupsScope(CodeGenFunction &CGF)
851       : PerformCleanup(true), CGF(CGF)
852     {
853       CleanupStackDepth = CGF.EHStack.stable_begin();
854       LifetimeExtendedCleanupStackSize =
855           CGF.LifetimeExtendedCleanupStack.size();
856       OldDidCallStackSave = CGF.DidCallStackSave;
857       CGF.DidCallStackSave = false;
858       OldCleanupScopeDepth = CGF.CurrentCleanupScopeDepth;
859       CGF.CurrentCleanupScopeDepth = CleanupStackDepth;
860     }
861 
862     /// Exit this cleanup scope, emitting any accumulated cleanups.
863     ~RunCleanupsScope() {
864       if (PerformCleanup)
865         ForceCleanup();
866     }
867 
868     /// Determine whether this scope requires any cleanups.
869     bool requiresCleanups() const {
870       return CGF.EHStack.stable_begin() != CleanupStackDepth;
871     }
872 
873     /// Force the emission of cleanups now, instead of waiting
874     /// until this object is destroyed.
875     /// \param ValuesToReload - A list of values that need to be available at
876     /// the insertion point after cleanup emission. If cleanup emission created
877     /// a shared cleanup block, these value pointers will be rewritten.
878     /// Otherwise, they not will be modified.
879     void ForceCleanup(std::initializer_list<llvm::Value**> ValuesToReload = {}) {
880       assert(PerformCleanup && "Already forced cleanup");
881       CGF.DidCallStackSave = OldDidCallStackSave;
882       CGF.PopCleanupBlocks(CleanupStackDepth, LifetimeExtendedCleanupStackSize,
883                            ValuesToReload);
884       PerformCleanup = false;
885       CGF.CurrentCleanupScopeDepth = OldCleanupScopeDepth;
886     }
887   };
888 
889   // Cleanup stack depth of the RunCleanupsScope that was pushed most recently.
890   EHScopeStack::stable_iterator CurrentCleanupScopeDepth =
891       EHScopeStack::stable_end();
892 
893   class LexicalScope : public RunCleanupsScope {
894     SourceRange Range;
895     SmallVector<const LabelDecl*, 4> Labels;
896     LexicalScope *ParentScope;
897 
898     LexicalScope(const LexicalScope &) = delete;
899     void operator=(const LexicalScope &) = delete;
900 
901   public:
902     /// Enter a new cleanup scope.
903     explicit LexicalScope(CodeGenFunction &CGF, SourceRange Range)
904       : RunCleanupsScope(CGF), Range(Range), ParentScope(CGF.CurLexicalScope) {
905       CGF.CurLexicalScope = this;
906       if (CGDebugInfo *DI = CGF.getDebugInfo())
907         DI->EmitLexicalBlockStart(CGF.Builder, Range.getBegin());
908     }
909 
910     void addLabel(const LabelDecl *label) {
911       assert(PerformCleanup && "adding label to dead scope?");
912       Labels.push_back(label);
913     }
914 
915     /// Exit this cleanup scope, emitting any accumulated
916     /// cleanups.
917     ~LexicalScope() {
918       if (CGDebugInfo *DI = CGF.getDebugInfo())
919         DI->EmitLexicalBlockEnd(CGF.Builder, Range.getEnd());
920 
921       // If we should perform a cleanup, force them now.  Note that
922       // this ends the cleanup scope before rescoping any labels.
923       if (PerformCleanup) {
924         ApplyDebugLocation DL(CGF, Range.getEnd());
925         ForceCleanup();
926       }
927     }
928 
929     /// Force the emission of cleanups now, instead of waiting
930     /// until this object is destroyed.
931     void ForceCleanup() {
932       CGF.CurLexicalScope = ParentScope;
933       RunCleanupsScope::ForceCleanup();
934 
935       if (!Labels.empty())
936         rescopeLabels();
937     }
938 
939     bool hasLabels() const {
940       return !Labels.empty();
941     }
942 
943     void rescopeLabels();
944   };
945 
946   typedef llvm::DenseMap<const Decl *, Address> DeclMapTy;
947 
948   /// The class used to assign some variables some temporarily addresses.
949   class OMPMapVars {
950     DeclMapTy SavedLocals;
951     DeclMapTy SavedTempAddresses;
952     OMPMapVars(const OMPMapVars &) = delete;
953     void operator=(const OMPMapVars &) = delete;
954 
955   public:
956     explicit OMPMapVars() = default;
957     ~OMPMapVars() {
958       assert(SavedLocals.empty() && "Did not restored original addresses.");
959     };
960 
961     /// Sets the address of the variable \p LocalVD to be \p TempAddr in
962     /// function \p CGF.
963     /// \return true if at least one variable was set already, false otherwise.
964     bool setVarAddr(CodeGenFunction &CGF, const VarDecl *LocalVD,
965                     Address TempAddr) {
966       LocalVD = LocalVD->getCanonicalDecl();
967       // Only save it once.
968       if (SavedLocals.count(LocalVD)) return false;
969 
970       // Copy the existing local entry to SavedLocals.
971       auto it = CGF.LocalDeclMap.find(LocalVD);
972       if (it != CGF.LocalDeclMap.end())
973         SavedLocals.try_emplace(LocalVD, it->second);
974       else
975         SavedLocals.try_emplace(LocalVD, Address::invalid());
976 
977       // Generate the private entry.
978       QualType VarTy = LocalVD->getType();
979       if (VarTy->isReferenceType()) {
980         Address Temp = CGF.CreateMemTemp(VarTy);
981         CGF.Builder.CreateStore(TempAddr.getPointer(), Temp);
982         TempAddr = Temp;
983       }
984       SavedTempAddresses.try_emplace(LocalVD, TempAddr);
985 
986       return true;
987     }
988 
989     /// Applies new addresses to the list of the variables.
990     /// \return true if at least one variable is using new address, false
991     /// otherwise.
992     bool apply(CodeGenFunction &CGF) {
993       copyInto(SavedTempAddresses, CGF.LocalDeclMap);
994       SavedTempAddresses.clear();
995       return !SavedLocals.empty();
996     }
997 
998     /// Restores original addresses of the variables.
999     void restore(CodeGenFunction &CGF) {
1000       if (!SavedLocals.empty()) {
1001         copyInto(SavedLocals, CGF.LocalDeclMap);
1002         SavedLocals.clear();
1003       }
1004     }
1005 
1006   private:
1007     /// Copy all the entries in the source map over the corresponding
1008     /// entries in the destination, which must exist.
1009     static void copyInto(const DeclMapTy &Src, DeclMapTy &Dest) {
1010       for (auto &Pair : Src) {
1011         if (!Pair.second.isValid()) {
1012           Dest.erase(Pair.first);
1013           continue;
1014         }
1015 
1016         auto I = Dest.find(Pair.first);
1017         if (I != Dest.end())
1018           I->second = Pair.second;
1019         else
1020           Dest.insert(Pair);
1021       }
1022     }
1023   };
1024 
1025   /// The scope used to remap some variables as private in the OpenMP loop body
1026   /// (or other captured region emitted without outlining), and to restore old
1027   /// vars back on exit.
1028   class OMPPrivateScope : public RunCleanupsScope {
1029     OMPMapVars MappedVars;
1030     OMPPrivateScope(const OMPPrivateScope &) = delete;
1031     void operator=(const OMPPrivateScope &) = delete;
1032 
1033   public:
1034     /// Enter a new OpenMP private scope.
1035     explicit OMPPrivateScope(CodeGenFunction &CGF) : RunCleanupsScope(CGF) {}
1036 
1037     /// Registers \p LocalVD variable as a private and apply \p PrivateGen
1038     /// function for it to generate corresponding private variable. \p
1039     /// PrivateGen returns an address of the generated private variable.
1040     /// \return true if the variable is registered as private, false if it has
1041     /// been privatized already.
1042     bool addPrivate(const VarDecl *LocalVD,
1043                     const llvm::function_ref<Address()> PrivateGen) {
1044       assert(PerformCleanup && "adding private to dead scope");
1045       return MappedVars.setVarAddr(CGF, LocalVD, PrivateGen());
1046     }
1047 
1048     /// Privatizes local variables previously registered as private.
1049     /// Registration is separate from the actual privatization to allow
1050     /// initializers use values of the original variables, not the private one.
1051     /// This is important, for example, if the private variable is a class
1052     /// variable initialized by a constructor that references other private
1053     /// variables. But at initialization original variables must be used, not
1054     /// private copies.
1055     /// \return true if at least one variable was privatized, false otherwise.
1056     bool Privatize() { return MappedVars.apply(CGF); }
1057 
1058     void ForceCleanup() {
1059       RunCleanupsScope::ForceCleanup();
1060       MappedVars.restore(CGF);
1061     }
1062 
1063     /// Exit scope - all the mapped variables are restored.
1064     ~OMPPrivateScope() {
1065       if (PerformCleanup)
1066         ForceCleanup();
1067     }
1068 
1069     /// Checks if the global variable is captured in current function.
1070     bool isGlobalVarCaptured(const VarDecl *VD) const {
1071       VD = VD->getCanonicalDecl();
1072       return !VD->isLocalVarDeclOrParm() && CGF.LocalDeclMap.count(VD) > 0;
1073     }
1074   };
1075 
1076   /// Save/restore original map of previously emitted local vars in case when we
1077   /// need to duplicate emission of the same code several times in the same
1078   /// function for OpenMP code.
1079   class OMPLocalDeclMapRAII {
1080     CodeGenFunction &CGF;
1081     DeclMapTy SavedMap;
1082 
1083   public:
1084     OMPLocalDeclMapRAII(CodeGenFunction &CGF)
1085         : CGF(CGF), SavedMap(CGF.LocalDeclMap) {}
1086     ~OMPLocalDeclMapRAII() { SavedMap.swap(CGF.LocalDeclMap); }
1087   };
1088 
1089   /// Takes the old cleanup stack size and emits the cleanup blocks
1090   /// that have been added.
1091   void
1092   PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
1093                    std::initializer_list<llvm::Value **> ValuesToReload = {});
1094 
1095   /// Takes the old cleanup stack size and emits the cleanup blocks
1096   /// that have been added, then adds all lifetime-extended cleanups from
1097   /// the given position to the stack.
1098   void
1099   PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
1100                    size_t OldLifetimeExtendedStackSize,
1101                    std::initializer_list<llvm::Value **> ValuesToReload = {});
1102 
1103   void ResolveBranchFixups(llvm::BasicBlock *Target);
1104 
1105   /// The given basic block lies in the current EH scope, but may be a
1106   /// target of a potentially scope-crossing jump; get a stable handle
1107   /// to which we can perform this jump later.
1108   JumpDest getJumpDestInCurrentScope(llvm::BasicBlock *Target) {
1109     return JumpDest(Target,
1110                     EHStack.getInnermostNormalCleanup(),
1111                     NextCleanupDestIndex++);
1112   }
1113 
1114   /// The given basic block lies in the current EH scope, but may be a
1115   /// target of a potentially scope-crossing jump; get a stable handle
1116   /// to which we can perform this jump later.
1117   JumpDest getJumpDestInCurrentScope(StringRef Name = StringRef()) {
1118     return getJumpDestInCurrentScope(createBasicBlock(Name));
1119   }
1120 
1121   /// EmitBranchThroughCleanup - Emit a branch from the current insert
1122   /// block through the normal cleanup handling code (if any) and then
1123   /// on to \arg Dest.
1124   void EmitBranchThroughCleanup(JumpDest Dest);
1125 
1126   /// isObviouslyBranchWithoutCleanups - Return true if a branch to the
1127   /// specified destination obviously has no cleanups to run.  'false' is always
1128   /// a conservatively correct answer for this method.
1129   bool isObviouslyBranchWithoutCleanups(JumpDest Dest) const;
1130 
1131   /// popCatchScope - Pops the catch scope at the top of the EHScope
1132   /// stack, emitting any required code (other than the catch handlers
1133   /// themselves).
1134   void popCatchScope();
1135 
1136   llvm::BasicBlock *getEHResumeBlock(bool isCleanup);
1137   llvm::BasicBlock *getEHDispatchBlock(EHScopeStack::stable_iterator scope);
1138   llvm::BasicBlock *
1139   getFuncletEHDispatchBlock(EHScopeStack::stable_iterator scope);
1140 
1141   /// An object to manage conditionally-evaluated expressions.
1142   class ConditionalEvaluation {
1143     llvm::BasicBlock *StartBB;
1144 
1145   public:
1146     ConditionalEvaluation(CodeGenFunction &CGF)
1147       : StartBB(CGF.Builder.GetInsertBlock()) {}
1148 
1149     void begin(CodeGenFunction &CGF) {
1150       assert(CGF.OutermostConditional != this);
1151       if (!CGF.OutermostConditional)
1152         CGF.OutermostConditional = this;
1153     }
1154 
1155     void end(CodeGenFunction &CGF) {
1156       assert(CGF.OutermostConditional != nullptr);
1157       if (CGF.OutermostConditional == this)
1158         CGF.OutermostConditional = nullptr;
1159     }
1160 
1161     /// Returns a block which will be executed prior to each
1162     /// evaluation of the conditional code.
1163     llvm::BasicBlock *getStartingBlock() const {
1164       return StartBB;
1165     }
1166   };
1167 
1168   /// isInConditionalBranch - Return true if we're currently emitting
1169   /// one branch or the other of a conditional expression.
1170   bool isInConditionalBranch() const { return OutermostConditional != nullptr; }
1171 
1172   void setBeforeOutermostConditional(llvm::Value *value, Address addr) {
1173     assert(isInConditionalBranch());
1174     llvm::BasicBlock *block = OutermostConditional->getStartingBlock();
1175     auto store = new llvm::StoreInst(value, addr.getPointer(), &block->back());
1176     store->setAlignment(addr.getAlignment().getAsAlign());
1177   }
1178 
1179   /// An RAII object to record that we're evaluating a statement
1180   /// expression.
1181   class StmtExprEvaluation {
1182     CodeGenFunction &CGF;
1183 
1184     /// We have to save the outermost conditional: cleanups in a
1185     /// statement expression aren't conditional just because the
1186     /// StmtExpr is.
1187     ConditionalEvaluation *SavedOutermostConditional;
1188 
1189   public:
1190     StmtExprEvaluation(CodeGenFunction &CGF)
1191       : CGF(CGF), SavedOutermostConditional(CGF.OutermostConditional) {
1192       CGF.OutermostConditional = nullptr;
1193     }
1194 
1195     ~StmtExprEvaluation() {
1196       CGF.OutermostConditional = SavedOutermostConditional;
1197       CGF.EnsureInsertPoint();
1198     }
1199   };
1200 
1201   /// An object which temporarily prevents a value from being
1202   /// destroyed by aggressive peephole optimizations that assume that
1203   /// all uses of a value have been realized in the IR.
1204   class PeepholeProtection {
1205     llvm::Instruction *Inst;
1206     friend class CodeGenFunction;
1207 
1208   public:
1209     PeepholeProtection() : Inst(nullptr) {}
1210   };
1211 
1212   /// A non-RAII class containing all the information about a bound
1213   /// opaque value.  OpaqueValueMapping, below, is a RAII wrapper for
1214   /// this which makes individual mappings very simple; using this
1215   /// class directly is useful when you have a variable number of
1216   /// opaque values or don't want the RAII functionality for some
1217   /// reason.
1218   class OpaqueValueMappingData {
1219     const OpaqueValueExpr *OpaqueValue;
1220     bool BoundLValue;
1221     CodeGenFunction::PeepholeProtection Protection;
1222 
1223     OpaqueValueMappingData(const OpaqueValueExpr *ov,
1224                            bool boundLValue)
1225       : OpaqueValue(ov), BoundLValue(boundLValue) {}
1226   public:
1227     OpaqueValueMappingData() : OpaqueValue(nullptr) {}
1228 
1229     static bool shouldBindAsLValue(const Expr *expr) {
1230       // gl-values should be bound as l-values for obvious reasons.
1231       // Records should be bound as l-values because IR generation
1232       // always keeps them in memory.  Expressions of function type
1233       // act exactly like l-values but are formally required to be
1234       // r-values in C.
1235       return expr->isGLValue() ||
1236              expr->getType()->isFunctionType() ||
1237              hasAggregateEvaluationKind(expr->getType());
1238     }
1239 
1240     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
1241                                        const OpaqueValueExpr *ov,
1242                                        const Expr *e) {
1243       if (shouldBindAsLValue(ov))
1244         return bind(CGF, ov, CGF.EmitLValue(e));
1245       return bind(CGF, ov, CGF.EmitAnyExpr(e));
1246     }
1247 
1248     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
1249                                        const OpaqueValueExpr *ov,
1250                                        const LValue &lv) {
1251       assert(shouldBindAsLValue(ov));
1252       CGF.OpaqueLValues.insert(std::make_pair(ov, lv));
1253       return OpaqueValueMappingData(ov, true);
1254     }
1255 
1256     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
1257                                        const OpaqueValueExpr *ov,
1258                                        const RValue &rv) {
1259       assert(!shouldBindAsLValue(ov));
1260       CGF.OpaqueRValues.insert(std::make_pair(ov, rv));
1261 
1262       OpaqueValueMappingData data(ov, false);
1263 
1264       // Work around an extremely aggressive peephole optimization in
1265       // EmitScalarConversion which assumes that all other uses of a
1266       // value are extant.
1267       data.Protection = CGF.protectFromPeepholes(rv);
1268 
1269       return data;
1270     }
1271 
1272     bool isValid() const { return OpaqueValue != nullptr; }
1273     void clear() { OpaqueValue = nullptr; }
1274 
1275     void unbind(CodeGenFunction &CGF) {
1276       assert(OpaqueValue && "no data to unbind!");
1277 
1278       if (BoundLValue) {
1279         CGF.OpaqueLValues.erase(OpaqueValue);
1280       } else {
1281         CGF.OpaqueRValues.erase(OpaqueValue);
1282         CGF.unprotectFromPeepholes(Protection);
1283       }
1284     }
1285   };
1286 
1287   /// An RAII object to set (and then clear) a mapping for an OpaqueValueExpr.
1288   class OpaqueValueMapping {
1289     CodeGenFunction &CGF;
1290     OpaqueValueMappingData Data;
1291 
1292   public:
1293     static bool shouldBindAsLValue(const Expr *expr) {
1294       return OpaqueValueMappingData::shouldBindAsLValue(expr);
1295     }
1296 
1297     /// Build the opaque value mapping for the given conditional
1298     /// operator if it's the GNU ?: extension.  This is a common
1299     /// enough pattern that the convenience operator is really
1300     /// helpful.
1301     ///
1302     OpaqueValueMapping(CodeGenFunction &CGF,
1303                        const AbstractConditionalOperator *op) : CGF(CGF) {
1304       if (isa<ConditionalOperator>(op))
1305         // Leave Data empty.
1306         return;
1307 
1308       const BinaryConditionalOperator *e = cast<BinaryConditionalOperator>(op);
1309       Data = OpaqueValueMappingData::bind(CGF, e->getOpaqueValue(),
1310                                           e->getCommon());
1311     }
1312 
1313     /// Build the opaque value mapping for an OpaqueValueExpr whose source
1314     /// expression is set to the expression the OVE represents.
1315     OpaqueValueMapping(CodeGenFunction &CGF, const OpaqueValueExpr *OV)
1316         : CGF(CGF) {
1317       if (OV) {
1318         assert(OV->getSourceExpr() && "wrong form of OpaqueValueMapping used "
1319                                       "for OVE with no source expression");
1320         Data = OpaqueValueMappingData::bind(CGF, OV, OV->getSourceExpr());
1321       }
1322     }
1323 
1324     OpaqueValueMapping(CodeGenFunction &CGF,
1325                        const OpaqueValueExpr *opaqueValue,
1326                        LValue lvalue)
1327       : CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, lvalue)) {
1328     }
1329 
1330     OpaqueValueMapping(CodeGenFunction &CGF,
1331                        const OpaqueValueExpr *opaqueValue,
1332                        RValue rvalue)
1333       : CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, rvalue)) {
1334     }
1335 
1336     void pop() {
1337       Data.unbind(CGF);
1338       Data.clear();
1339     }
1340 
1341     ~OpaqueValueMapping() {
1342       if (Data.isValid()) Data.unbind(CGF);
1343     }
1344   };
1345 
1346 private:
1347   CGDebugInfo *DebugInfo;
1348   /// Used to create unique names for artificial VLA size debug info variables.
1349   unsigned VLAExprCounter = 0;
1350   bool DisableDebugInfo = false;
1351 
1352   /// DidCallStackSave - Whether llvm.stacksave has been called. Used to avoid
1353   /// calling llvm.stacksave for multiple VLAs in the same scope.
1354   bool DidCallStackSave = false;
1355 
1356   /// IndirectBranch - The first time an indirect goto is seen we create a block
1357   /// with an indirect branch.  Every time we see the address of a label taken,
1358   /// we add the label to the indirect goto.  Every subsequent indirect goto is
1359   /// codegen'd as a jump to the IndirectBranch's basic block.
1360   llvm::IndirectBrInst *IndirectBranch = nullptr;
1361 
1362   /// LocalDeclMap - This keeps track of the LLVM allocas or globals for local C
1363   /// decls.
1364   DeclMapTy LocalDeclMap;
1365 
1366   // Keep track of the cleanups for callee-destructed parameters pushed to the
1367   // cleanup stack so that they can be deactivated later.
1368   llvm::DenseMap<const ParmVarDecl *, EHScopeStack::stable_iterator>
1369       CalleeDestructedParamCleanups;
1370 
1371   /// SizeArguments - If a ParmVarDecl had the pass_object_size attribute, this
1372   /// will contain a mapping from said ParmVarDecl to its implicit "object_size"
1373   /// parameter.
1374   llvm::SmallDenseMap<const ParmVarDecl *, const ImplicitParamDecl *, 2>
1375       SizeArguments;
1376 
1377   /// Track escaped local variables with auto storage. Used during SEH
1378   /// outlining to produce a call to llvm.localescape.
1379   llvm::DenseMap<llvm::AllocaInst *, int> EscapedLocals;
1380 
1381   /// LabelMap - This keeps track of the LLVM basic block for each C label.
1382   llvm::DenseMap<const LabelDecl*, JumpDest> LabelMap;
1383 
1384   // BreakContinueStack - This keeps track of where break and continue
1385   // statements should jump to.
1386   struct BreakContinue {
1387     BreakContinue(JumpDest Break, JumpDest Continue)
1388       : BreakBlock(Break), ContinueBlock(Continue) {}
1389 
1390     JumpDest BreakBlock;
1391     JumpDest ContinueBlock;
1392   };
1393   SmallVector<BreakContinue, 8> BreakContinueStack;
1394 
1395   /// Handles cancellation exit points in OpenMP-related constructs.
1396   class OpenMPCancelExitStack {
1397     /// Tracks cancellation exit point and join point for cancel-related exit
1398     /// and normal exit.
1399     struct CancelExit {
1400       CancelExit() = default;
1401       CancelExit(OpenMPDirectiveKind Kind, JumpDest ExitBlock,
1402                  JumpDest ContBlock)
1403           : Kind(Kind), ExitBlock(ExitBlock), ContBlock(ContBlock) {}
1404       OpenMPDirectiveKind Kind = llvm::omp::OMPD_unknown;
1405       /// true if the exit block has been emitted already by the special
1406       /// emitExit() call, false if the default codegen is used.
1407       bool HasBeenEmitted = false;
1408       JumpDest ExitBlock;
1409       JumpDest ContBlock;
1410     };
1411 
1412     SmallVector<CancelExit, 8> Stack;
1413 
1414   public:
1415     OpenMPCancelExitStack() : Stack(1) {}
1416     ~OpenMPCancelExitStack() = default;
1417     /// Fetches the exit block for the current OpenMP construct.
1418     JumpDest getExitBlock() const { return Stack.back().ExitBlock; }
1419     /// Emits exit block with special codegen procedure specific for the related
1420     /// OpenMP construct + emits code for normal construct cleanup.
1421     void emitExit(CodeGenFunction &CGF, OpenMPDirectiveKind Kind,
1422                   const llvm::function_ref<void(CodeGenFunction &)> CodeGen) {
1423       if (Stack.back().Kind == Kind && getExitBlock().isValid()) {
1424         assert(CGF.getOMPCancelDestination(Kind).isValid());
1425         assert(CGF.HaveInsertPoint());
1426         assert(!Stack.back().HasBeenEmitted);
1427         auto IP = CGF.Builder.saveAndClearIP();
1428         CGF.EmitBlock(Stack.back().ExitBlock.getBlock());
1429         CodeGen(CGF);
1430         CGF.EmitBranch(Stack.back().ContBlock.getBlock());
1431         CGF.Builder.restoreIP(IP);
1432         Stack.back().HasBeenEmitted = true;
1433       }
1434       CodeGen(CGF);
1435     }
1436     /// Enter the cancel supporting \a Kind construct.
1437     /// \param Kind OpenMP directive that supports cancel constructs.
1438     /// \param HasCancel true, if the construct has inner cancel directive,
1439     /// false otherwise.
1440     void enter(CodeGenFunction &CGF, OpenMPDirectiveKind Kind, bool HasCancel) {
1441       Stack.push_back({Kind,
1442                        HasCancel ? CGF.getJumpDestInCurrentScope("cancel.exit")
1443                                  : JumpDest(),
1444                        HasCancel ? CGF.getJumpDestInCurrentScope("cancel.cont")
1445                                  : JumpDest()});
1446     }
1447     /// Emits default exit point for the cancel construct (if the special one
1448     /// has not be used) + join point for cancel/normal exits.
1449     void exit(CodeGenFunction &CGF) {
1450       if (getExitBlock().isValid()) {
1451         assert(CGF.getOMPCancelDestination(Stack.back().Kind).isValid());
1452         bool HaveIP = CGF.HaveInsertPoint();
1453         if (!Stack.back().HasBeenEmitted) {
1454           if (HaveIP)
1455             CGF.EmitBranchThroughCleanup(Stack.back().ContBlock);
1456           CGF.EmitBlock(Stack.back().ExitBlock.getBlock());
1457           CGF.EmitBranchThroughCleanup(Stack.back().ContBlock);
1458         }
1459         CGF.EmitBlock(Stack.back().ContBlock.getBlock());
1460         if (!HaveIP) {
1461           CGF.Builder.CreateUnreachable();
1462           CGF.Builder.ClearInsertionPoint();
1463         }
1464       }
1465       Stack.pop_back();
1466     }
1467   };
1468   OpenMPCancelExitStack OMPCancelStack;
1469 
1470   /// Lower the Likelihood knowledge about the \p Cond via llvm.expect intrin.
1471   llvm::Value *emitCondLikelihoodViaExpectIntrinsic(llvm::Value *Cond,
1472                                                     Stmt::Likelihood LH);
1473 
1474   CodeGenPGO PGO;
1475 
1476   /// Calculate branch weights appropriate for PGO data
1477   llvm::MDNode *createProfileWeights(uint64_t TrueCount,
1478                                      uint64_t FalseCount) const;
1479   llvm::MDNode *createProfileWeights(ArrayRef<uint64_t> Weights) const;
1480   llvm::MDNode *createProfileWeightsForLoop(const Stmt *Cond,
1481                                             uint64_t LoopCount) const;
1482 
1483 public:
1484   /// Increment the profiler's counter for the given statement by \p StepV.
1485   /// If \p StepV is null, the default increment is 1.
1486   void incrementProfileCounter(const Stmt *S, llvm::Value *StepV = nullptr) {
1487     if (CGM.getCodeGenOpts().hasProfileClangInstr() &&
1488         !CurFn->hasFnAttribute(llvm::Attribute::NoProfile))
1489       PGO.emitCounterIncrement(Builder, S, StepV);
1490     PGO.setCurrentStmt(S);
1491   }
1492 
1493   /// Get the profiler's count for the given statement.
1494   uint64_t getProfileCount(const Stmt *S) {
1495     Optional<uint64_t> Count = PGO.getStmtCount(S);
1496     if (!Count.hasValue())
1497       return 0;
1498     return *Count;
1499   }
1500 
1501   /// Set the profiler's current count.
1502   void setCurrentProfileCount(uint64_t Count) {
1503     PGO.setCurrentRegionCount(Count);
1504   }
1505 
1506   /// Get the profiler's current count. This is generally the count for the most
1507   /// recently incremented counter.
1508   uint64_t getCurrentProfileCount() {
1509     return PGO.getCurrentRegionCount();
1510   }
1511 
1512 private:
1513 
1514   /// SwitchInsn - This is nearest current switch instruction. It is null if
1515   /// current context is not in a switch.
1516   llvm::SwitchInst *SwitchInsn = nullptr;
1517   /// The branch weights of SwitchInsn when doing instrumentation based PGO.
1518   SmallVector<uint64_t, 16> *SwitchWeights = nullptr;
1519 
1520   /// The likelihood attributes of the SwitchCase.
1521   SmallVector<Stmt::Likelihood, 16> *SwitchLikelihood = nullptr;
1522 
1523   /// CaseRangeBlock - This block holds if condition check for last case
1524   /// statement range in current switch instruction.
1525   llvm::BasicBlock *CaseRangeBlock = nullptr;
1526 
1527   /// OpaqueLValues - Keeps track of the current set of opaque value
1528   /// expressions.
1529   llvm::DenseMap<const OpaqueValueExpr *, LValue> OpaqueLValues;
1530   llvm::DenseMap<const OpaqueValueExpr *, RValue> OpaqueRValues;
1531 
1532   // VLASizeMap - This keeps track of the associated size for each VLA type.
1533   // We track this by the size expression rather than the type itself because
1534   // in certain situations, like a const qualifier applied to an VLA typedef,
1535   // multiple VLA types can share the same size expression.
1536   // FIXME: Maybe this could be a stack of maps that is pushed/popped as we
1537   // enter/leave scopes.
1538   llvm::DenseMap<const Expr*, llvm::Value*> VLASizeMap;
1539 
1540   /// A block containing a single 'unreachable' instruction.  Created
1541   /// lazily by getUnreachableBlock().
1542   llvm::BasicBlock *UnreachableBlock = nullptr;
1543 
1544   /// Counts of the number return expressions in the function.
1545   unsigned NumReturnExprs = 0;
1546 
1547   /// Count the number of simple (constant) return expressions in the function.
1548   unsigned NumSimpleReturnExprs = 0;
1549 
1550   /// The last regular (non-return) debug location (breakpoint) in the function.
1551   SourceLocation LastStopPoint;
1552 
1553 public:
1554   /// Source location information about the default argument or member
1555   /// initializer expression we're evaluating, if any.
1556   CurrentSourceLocExprScope CurSourceLocExprScope;
1557   using SourceLocExprScopeGuard =
1558       CurrentSourceLocExprScope::SourceLocExprScopeGuard;
1559 
1560   /// A scope within which we are constructing the fields of an object which
1561   /// might use a CXXDefaultInitExpr. This stashes away a 'this' value to use
1562   /// if we need to evaluate a CXXDefaultInitExpr within the evaluation.
1563   class FieldConstructionScope {
1564   public:
1565     FieldConstructionScope(CodeGenFunction &CGF, Address This)
1566         : CGF(CGF), OldCXXDefaultInitExprThis(CGF.CXXDefaultInitExprThis) {
1567       CGF.CXXDefaultInitExprThis = This;
1568     }
1569     ~FieldConstructionScope() {
1570       CGF.CXXDefaultInitExprThis = OldCXXDefaultInitExprThis;
1571     }
1572 
1573   private:
1574     CodeGenFunction &CGF;
1575     Address OldCXXDefaultInitExprThis;
1576   };
1577 
1578   /// The scope of a CXXDefaultInitExpr. Within this scope, the value of 'this'
1579   /// is overridden to be the object under construction.
1580   class CXXDefaultInitExprScope  {
1581   public:
1582     CXXDefaultInitExprScope(CodeGenFunction &CGF, const CXXDefaultInitExpr *E)
1583         : CGF(CGF), OldCXXThisValue(CGF.CXXThisValue),
1584           OldCXXThisAlignment(CGF.CXXThisAlignment),
1585           SourceLocScope(E, CGF.CurSourceLocExprScope) {
1586       CGF.CXXThisValue = CGF.CXXDefaultInitExprThis.getPointer();
1587       CGF.CXXThisAlignment = CGF.CXXDefaultInitExprThis.getAlignment();
1588     }
1589     ~CXXDefaultInitExprScope() {
1590       CGF.CXXThisValue = OldCXXThisValue;
1591       CGF.CXXThisAlignment = OldCXXThisAlignment;
1592     }
1593 
1594   public:
1595     CodeGenFunction &CGF;
1596     llvm::Value *OldCXXThisValue;
1597     CharUnits OldCXXThisAlignment;
1598     SourceLocExprScopeGuard SourceLocScope;
1599   };
1600 
1601   struct CXXDefaultArgExprScope : SourceLocExprScopeGuard {
1602     CXXDefaultArgExprScope(CodeGenFunction &CGF, const CXXDefaultArgExpr *E)
1603         : SourceLocExprScopeGuard(E, CGF.CurSourceLocExprScope) {}
1604   };
1605 
1606   /// The scope of an ArrayInitLoopExpr. Within this scope, the value of the
1607   /// current loop index is overridden.
1608   class ArrayInitLoopExprScope {
1609   public:
1610     ArrayInitLoopExprScope(CodeGenFunction &CGF, llvm::Value *Index)
1611       : CGF(CGF), OldArrayInitIndex(CGF.ArrayInitIndex) {
1612       CGF.ArrayInitIndex = Index;
1613     }
1614     ~ArrayInitLoopExprScope() {
1615       CGF.ArrayInitIndex = OldArrayInitIndex;
1616     }
1617 
1618   private:
1619     CodeGenFunction &CGF;
1620     llvm::Value *OldArrayInitIndex;
1621   };
1622 
1623   class InlinedInheritingConstructorScope {
1624   public:
1625     InlinedInheritingConstructorScope(CodeGenFunction &CGF, GlobalDecl GD)
1626         : CGF(CGF), OldCurGD(CGF.CurGD), OldCurFuncDecl(CGF.CurFuncDecl),
1627           OldCurCodeDecl(CGF.CurCodeDecl),
1628           OldCXXABIThisDecl(CGF.CXXABIThisDecl),
1629           OldCXXABIThisValue(CGF.CXXABIThisValue),
1630           OldCXXThisValue(CGF.CXXThisValue),
1631           OldCXXABIThisAlignment(CGF.CXXABIThisAlignment),
1632           OldCXXThisAlignment(CGF.CXXThisAlignment),
1633           OldReturnValue(CGF.ReturnValue), OldFnRetTy(CGF.FnRetTy),
1634           OldCXXInheritedCtorInitExprArgs(
1635               std::move(CGF.CXXInheritedCtorInitExprArgs)) {
1636       CGF.CurGD = GD;
1637       CGF.CurFuncDecl = CGF.CurCodeDecl =
1638           cast<CXXConstructorDecl>(GD.getDecl());
1639       CGF.CXXABIThisDecl = nullptr;
1640       CGF.CXXABIThisValue = nullptr;
1641       CGF.CXXThisValue = nullptr;
1642       CGF.CXXABIThisAlignment = CharUnits();
1643       CGF.CXXThisAlignment = CharUnits();
1644       CGF.ReturnValue = Address::invalid();
1645       CGF.FnRetTy = QualType();
1646       CGF.CXXInheritedCtorInitExprArgs.clear();
1647     }
1648     ~InlinedInheritingConstructorScope() {
1649       CGF.CurGD = OldCurGD;
1650       CGF.CurFuncDecl = OldCurFuncDecl;
1651       CGF.CurCodeDecl = OldCurCodeDecl;
1652       CGF.CXXABIThisDecl = OldCXXABIThisDecl;
1653       CGF.CXXABIThisValue = OldCXXABIThisValue;
1654       CGF.CXXThisValue = OldCXXThisValue;
1655       CGF.CXXABIThisAlignment = OldCXXABIThisAlignment;
1656       CGF.CXXThisAlignment = OldCXXThisAlignment;
1657       CGF.ReturnValue = OldReturnValue;
1658       CGF.FnRetTy = OldFnRetTy;
1659       CGF.CXXInheritedCtorInitExprArgs =
1660           std::move(OldCXXInheritedCtorInitExprArgs);
1661     }
1662 
1663   private:
1664     CodeGenFunction &CGF;
1665     GlobalDecl OldCurGD;
1666     const Decl *OldCurFuncDecl;
1667     const Decl *OldCurCodeDecl;
1668     ImplicitParamDecl *OldCXXABIThisDecl;
1669     llvm::Value *OldCXXABIThisValue;
1670     llvm::Value *OldCXXThisValue;
1671     CharUnits OldCXXABIThisAlignment;
1672     CharUnits OldCXXThisAlignment;
1673     Address OldReturnValue;
1674     QualType OldFnRetTy;
1675     CallArgList OldCXXInheritedCtorInitExprArgs;
1676   };
1677 
1678   // Helper class for the OpenMP IR Builder. Allows reusability of code used for
1679   // region body, and finalization codegen callbacks. This will class will also
1680   // contain privatization functions used by the privatization call backs
1681   //
1682   // TODO: this is temporary class for things that are being moved out of
1683   // CGOpenMPRuntime, new versions of current CodeGenFunction methods, or
1684   // utility function for use with the OMPBuilder. Once that move to use the
1685   // OMPBuilder is done, everything here will either become part of CodeGenFunc.
1686   // directly, or a new helper class that will contain functions used by both
1687   // this and the OMPBuilder
1688 
1689   struct OMPBuilderCBHelpers {
1690 
1691     OMPBuilderCBHelpers() = delete;
1692     OMPBuilderCBHelpers(const OMPBuilderCBHelpers &) = delete;
1693     OMPBuilderCBHelpers &operator=(const OMPBuilderCBHelpers &) = delete;
1694 
1695     using InsertPointTy = llvm::OpenMPIRBuilder::InsertPointTy;
1696 
1697     /// Cleanup action for allocate support.
1698     class OMPAllocateCleanupTy final : public EHScopeStack::Cleanup {
1699 
1700     private:
1701       llvm::CallInst *RTLFnCI;
1702 
1703     public:
1704       OMPAllocateCleanupTy(llvm::CallInst *RLFnCI) : RTLFnCI(RLFnCI) {
1705         RLFnCI->removeFromParent();
1706       }
1707 
1708       void Emit(CodeGenFunction &CGF, Flags /*flags*/) override {
1709         if (!CGF.HaveInsertPoint())
1710           return;
1711         CGF.Builder.Insert(RTLFnCI);
1712       }
1713     };
1714 
1715     /// Returns address of the threadprivate variable for the current
1716     /// thread. This Also create any necessary OMP runtime calls.
1717     ///
1718     /// \param VD VarDecl for Threadprivate variable.
1719     /// \param VDAddr Address of the Vardecl
1720     /// \param Loc  The location where the barrier directive was encountered
1721     static Address getAddrOfThreadPrivate(CodeGenFunction &CGF,
1722                                           const VarDecl *VD, Address VDAddr,
1723                                           SourceLocation Loc);
1724 
1725     /// Gets the OpenMP-specific address of the local variable /p VD.
1726     static Address getAddressOfLocalVariable(CodeGenFunction &CGF,
1727                                              const VarDecl *VD);
1728     /// Get the platform-specific name separator.
1729     /// \param Parts different parts of the final name that needs separation
1730     /// \param FirstSeparator First separator used between the initial two
1731     ///        parts of the name.
1732     /// \param Separator separator used between all of the rest consecutinve
1733     ///        parts of the name
1734     static std::string getNameWithSeparators(ArrayRef<StringRef> Parts,
1735                                              StringRef FirstSeparator = ".",
1736                                              StringRef Separator = ".");
1737     /// Emit the Finalization for an OMP region
1738     /// \param CGF	The Codegen function this belongs to
1739     /// \param IP	Insertion point for generating the finalization code.
1740     static void FinalizeOMPRegion(CodeGenFunction &CGF, InsertPointTy IP) {
1741       CGBuilderTy::InsertPointGuard IPG(CGF.Builder);
1742       assert(IP.getBlock()->end() != IP.getPoint() &&
1743              "OpenMP IR Builder should cause terminated block!");
1744 
1745       llvm::BasicBlock *IPBB = IP.getBlock();
1746       llvm::BasicBlock *DestBB = IPBB->getUniqueSuccessor();
1747       assert(DestBB && "Finalization block should have one successor!");
1748 
1749       // erase and replace with cleanup branch.
1750       IPBB->getTerminator()->eraseFromParent();
1751       CGF.Builder.SetInsertPoint(IPBB);
1752       CodeGenFunction::JumpDest Dest = CGF.getJumpDestInCurrentScope(DestBB);
1753       CGF.EmitBranchThroughCleanup(Dest);
1754     }
1755 
1756     /// Emit the body of an OMP region
1757     /// \param CGF	The Codegen function this belongs to
1758     /// \param RegionBodyStmt	The body statement for the OpenMP region being
1759     /// 			 generated
1760     /// \param CodeGenIP	Insertion point for generating the body code.
1761     /// \param FiniBB	The finalization basic block
1762     static void EmitOMPRegionBody(CodeGenFunction &CGF,
1763                                   const Stmt *RegionBodyStmt,
1764                                   InsertPointTy CodeGenIP,
1765                                   llvm::BasicBlock &FiniBB) {
1766       llvm::BasicBlock *CodeGenIPBB = CodeGenIP.getBlock();
1767       if (llvm::Instruction *CodeGenIPBBTI = CodeGenIPBB->getTerminator())
1768         CodeGenIPBBTI->eraseFromParent();
1769 
1770       CGF.Builder.SetInsertPoint(CodeGenIPBB);
1771 
1772       CGF.EmitStmt(RegionBodyStmt);
1773 
1774       if (CGF.Builder.saveIP().isSet())
1775         CGF.Builder.CreateBr(&FiniBB);
1776     }
1777 
1778     /// RAII for preserving necessary info during Outlined region body codegen.
1779     class OutlinedRegionBodyRAII {
1780 
1781       llvm::AssertingVH<llvm::Instruction> OldAllocaIP;
1782       CodeGenFunction::JumpDest OldReturnBlock;
1783       CGBuilderTy::InsertPoint IP;
1784       CodeGenFunction &CGF;
1785 
1786     public:
1787       OutlinedRegionBodyRAII(CodeGenFunction &cgf, InsertPointTy &AllocaIP,
1788                              llvm::BasicBlock &RetBB)
1789           : CGF(cgf) {
1790         assert(AllocaIP.isSet() &&
1791                "Must specify Insertion point for allocas of outlined function");
1792         OldAllocaIP = CGF.AllocaInsertPt;
1793         CGF.AllocaInsertPt = &*AllocaIP.getPoint();
1794         IP = CGF.Builder.saveIP();
1795 
1796         OldReturnBlock = CGF.ReturnBlock;
1797         CGF.ReturnBlock = CGF.getJumpDestInCurrentScope(&RetBB);
1798       }
1799 
1800       ~OutlinedRegionBodyRAII() {
1801         CGF.AllocaInsertPt = OldAllocaIP;
1802         CGF.ReturnBlock = OldReturnBlock;
1803         CGF.Builder.restoreIP(IP);
1804       }
1805     };
1806 
1807     /// RAII for preserving necessary info during inlined region body codegen.
1808     class InlinedRegionBodyRAII {
1809 
1810       llvm::AssertingVH<llvm::Instruction> OldAllocaIP;
1811       CodeGenFunction &CGF;
1812 
1813     public:
1814       InlinedRegionBodyRAII(CodeGenFunction &cgf, InsertPointTy &AllocaIP,
1815                             llvm::BasicBlock &FiniBB)
1816           : CGF(cgf) {
1817         // Alloca insertion block should be in the entry block of the containing
1818         // function so it expects an empty AllocaIP in which case will reuse the
1819         // old alloca insertion point, or a new AllocaIP in the same block as
1820         // the old one
1821         assert((!AllocaIP.isSet() ||
1822                 CGF.AllocaInsertPt->getParent() == AllocaIP.getBlock()) &&
1823                "Insertion point should be in the entry block of containing "
1824                "function!");
1825         OldAllocaIP = CGF.AllocaInsertPt;
1826         if (AllocaIP.isSet())
1827           CGF.AllocaInsertPt = &*AllocaIP.getPoint();
1828 
1829         // TODO: Remove the call, after making sure the counter is not used by
1830         //       the EHStack.
1831         // Since this is an inlined region, it should not modify the
1832         // ReturnBlock, and should reuse the one for the enclosing outlined
1833         // region. So, the JumpDest being return by the function is discarded
1834         (void)CGF.getJumpDestInCurrentScope(&FiniBB);
1835       }
1836 
1837       ~InlinedRegionBodyRAII() { CGF.AllocaInsertPt = OldAllocaIP; }
1838     };
1839   };
1840 
1841 private:
1842   /// CXXThisDecl - When generating code for a C++ member function,
1843   /// this will hold the implicit 'this' declaration.
1844   ImplicitParamDecl *CXXABIThisDecl = nullptr;
1845   llvm::Value *CXXABIThisValue = nullptr;
1846   llvm::Value *CXXThisValue = nullptr;
1847   CharUnits CXXABIThisAlignment;
1848   CharUnits CXXThisAlignment;
1849 
1850   /// The value of 'this' to use when evaluating CXXDefaultInitExprs within
1851   /// this expression.
1852   Address CXXDefaultInitExprThis = Address::invalid();
1853 
1854   /// The current array initialization index when evaluating an
1855   /// ArrayInitIndexExpr within an ArrayInitLoopExpr.
1856   llvm::Value *ArrayInitIndex = nullptr;
1857 
1858   /// The values of function arguments to use when evaluating
1859   /// CXXInheritedCtorInitExprs within this context.
1860   CallArgList CXXInheritedCtorInitExprArgs;
1861 
1862   /// CXXStructorImplicitParamDecl - When generating code for a constructor or
1863   /// destructor, this will hold the implicit argument (e.g. VTT).
1864   ImplicitParamDecl *CXXStructorImplicitParamDecl = nullptr;
1865   llvm::Value *CXXStructorImplicitParamValue = nullptr;
1866 
1867   /// OutermostConditional - Points to the outermost active
1868   /// conditional control.  This is used so that we know if a
1869   /// temporary should be destroyed conditionally.
1870   ConditionalEvaluation *OutermostConditional = nullptr;
1871 
1872   /// The current lexical scope.
1873   LexicalScope *CurLexicalScope = nullptr;
1874 
1875   /// The current source location that should be used for exception
1876   /// handling code.
1877   SourceLocation CurEHLocation;
1878 
1879   /// BlockByrefInfos - For each __block variable, contains
1880   /// information about the layout of the variable.
1881   llvm::DenseMap<const ValueDecl *, BlockByrefInfo> BlockByrefInfos;
1882 
1883   /// Used by -fsanitize=nullability-return to determine whether the return
1884   /// value can be checked.
1885   llvm::Value *RetValNullabilityPrecondition = nullptr;
1886 
1887   /// Check if -fsanitize=nullability-return instrumentation is required for
1888   /// this function.
1889   bool requiresReturnValueNullabilityCheck() const {
1890     return RetValNullabilityPrecondition;
1891   }
1892 
1893   /// Used to store precise source locations for return statements by the
1894   /// runtime return value checks.
1895   Address ReturnLocation = Address::invalid();
1896 
1897   /// Check if the return value of this function requires sanitization.
1898   bool requiresReturnValueCheck() const;
1899 
1900   llvm::BasicBlock *TerminateLandingPad = nullptr;
1901   llvm::BasicBlock *TerminateHandler = nullptr;
1902   llvm::SmallVector<llvm::BasicBlock *, 2> TrapBBs;
1903 
1904   /// Terminate funclets keyed by parent funclet pad.
1905   llvm::MapVector<llvm::Value *, llvm::BasicBlock *> TerminateFunclets;
1906 
1907   /// Largest vector width used in ths function. Will be used to create a
1908   /// function attribute.
1909   unsigned LargestVectorWidth = 0;
1910 
1911   /// True if we need emit the life-time markers. This is initially set in
1912   /// the constructor, but could be overwritten to true if this is a coroutine.
1913   bool ShouldEmitLifetimeMarkers;
1914 
1915   /// Add OpenCL kernel arg metadata and the kernel attribute metadata to
1916   /// the function metadata.
1917   void EmitOpenCLKernelMetadata(const FunctionDecl *FD,
1918                                 llvm::Function *Fn);
1919 
1920 public:
1921   CodeGenFunction(CodeGenModule &cgm, bool suppressNewContext=false);
1922   ~CodeGenFunction();
1923 
1924   CodeGenTypes &getTypes() const { return CGM.getTypes(); }
1925   ASTContext &getContext() const { return CGM.getContext(); }
1926   CGDebugInfo *getDebugInfo() {
1927     if (DisableDebugInfo)
1928       return nullptr;
1929     return DebugInfo;
1930   }
1931   void disableDebugInfo() { DisableDebugInfo = true; }
1932   void enableDebugInfo() { DisableDebugInfo = false; }
1933 
1934   bool shouldUseFusedARCCalls() {
1935     return CGM.getCodeGenOpts().OptimizationLevel == 0;
1936   }
1937 
1938   const LangOptions &getLangOpts() const { return CGM.getLangOpts(); }
1939 
1940   /// Returns a pointer to the function's exception object and selector slot,
1941   /// which is assigned in every landing pad.
1942   Address getExceptionSlot();
1943   Address getEHSelectorSlot();
1944 
1945   /// Returns the contents of the function's exception object and selector
1946   /// slots.
1947   llvm::Value *getExceptionFromSlot();
1948   llvm::Value *getSelectorFromSlot();
1949 
1950   Address getNormalCleanupDestSlot();
1951 
1952   llvm::BasicBlock *getUnreachableBlock() {
1953     if (!UnreachableBlock) {
1954       UnreachableBlock = createBasicBlock("unreachable");
1955       new llvm::UnreachableInst(getLLVMContext(), UnreachableBlock);
1956     }
1957     return UnreachableBlock;
1958   }
1959 
1960   llvm::BasicBlock *getInvokeDest() {
1961     if (!EHStack.requiresLandingPad()) return nullptr;
1962     return getInvokeDestImpl();
1963   }
1964 
1965   bool currentFunctionUsesSEHTry() const { return CurSEHParent != nullptr; }
1966 
1967   const TargetInfo &getTarget() const { return Target; }
1968   llvm::LLVMContext &getLLVMContext() { return CGM.getLLVMContext(); }
1969   const TargetCodeGenInfo &getTargetHooks() const {
1970     return CGM.getTargetCodeGenInfo();
1971   }
1972 
1973   //===--------------------------------------------------------------------===//
1974   //                                  Cleanups
1975   //===--------------------------------------------------------------------===//
1976 
1977   typedef void Destroyer(CodeGenFunction &CGF, Address addr, QualType ty);
1978 
1979   void pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
1980                                         Address arrayEndPointer,
1981                                         QualType elementType,
1982                                         CharUnits elementAlignment,
1983                                         Destroyer *destroyer);
1984   void pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
1985                                       llvm::Value *arrayEnd,
1986                                       QualType elementType,
1987                                       CharUnits elementAlignment,
1988                                       Destroyer *destroyer);
1989 
1990   void pushDestroy(QualType::DestructionKind dtorKind,
1991                    Address addr, QualType type);
1992   void pushEHDestroy(QualType::DestructionKind dtorKind,
1993                      Address addr, QualType type);
1994   void pushDestroy(CleanupKind kind, Address addr, QualType type,
1995                    Destroyer *destroyer, bool useEHCleanupForArray);
1996   void pushLifetimeExtendedDestroy(CleanupKind kind, Address addr,
1997                                    QualType type, Destroyer *destroyer,
1998                                    bool useEHCleanupForArray);
1999   void pushCallObjectDeleteCleanup(const FunctionDecl *OperatorDelete,
2000                                    llvm::Value *CompletePtr,
2001                                    QualType ElementType);
2002   void pushStackRestore(CleanupKind kind, Address SPMem);
2003   void emitDestroy(Address addr, QualType type, Destroyer *destroyer,
2004                    bool useEHCleanupForArray);
2005   llvm::Function *generateDestroyHelper(Address addr, QualType type,
2006                                         Destroyer *destroyer,
2007                                         bool useEHCleanupForArray,
2008                                         const VarDecl *VD);
2009   void emitArrayDestroy(llvm::Value *begin, llvm::Value *end,
2010                         QualType elementType, CharUnits elementAlign,
2011                         Destroyer *destroyer,
2012                         bool checkZeroLength, bool useEHCleanup);
2013 
2014   Destroyer *getDestroyer(QualType::DestructionKind destructionKind);
2015 
2016   /// Determines whether an EH cleanup is required to destroy a type
2017   /// with the given destruction kind.
2018   bool needsEHCleanup(QualType::DestructionKind kind) {
2019     switch (kind) {
2020     case QualType::DK_none:
2021       return false;
2022     case QualType::DK_cxx_destructor:
2023     case QualType::DK_objc_weak_lifetime:
2024     case QualType::DK_nontrivial_c_struct:
2025       return getLangOpts().Exceptions;
2026     case QualType::DK_objc_strong_lifetime:
2027       return getLangOpts().Exceptions &&
2028              CGM.getCodeGenOpts().ObjCAutoRefCountExceptions;
2029     }
2030     llvm_unreachable("bad destruction kind");
2031   }
2032 
2033   CleanupKind getCleanupKind(QualType::DestructionKind kind) {
2034     return (needsEHCleanup(kind) ? NormalAndEHCleanup : NormalCleanup);
2035   }
2036 
2037   //===--------------------------------------------------------------------===//
2038   //                                  Objective-C
2039   //===--------------------------------------------------------------------===//
2040 
2041   void GenerateObjCMethod(const ObjCMethodDecl *OMD);
2042 
2043   void StartObjCMethod(const ObjCMethodDecl *MD, const ObjCContainerDecl *CD);
2044 
2045   /// GenerateObjCGetter - Synthesize an Objective-C property getter function.
2046   void GenerateObjCGetter(ObjCImplementationDecl *IMP,
2047                           const ObjCPropertyImplDecl *PID);
2048   void generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
2049                               const ObjCPropertyImplDecl *propImpl,
2050                               const ObjCMethodDecl *GetterMothodDecl,
2051                               llvm::Constant *AtomicHelperFn);
2052 
2053   void GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
2054                                   ObjCMethodDecl *MD, bool ctor);
2055 
2056   /// GenerateObjCSetter - Synthesize an Objective-C property setter function
2057   /// for the given property.
2058   void GenerateObjCSetter(ObjCImplementationDecl *IMP,
2059                           const ObjCPropertyImplDecl *PID);
2060   void generateObjCSetterBody(const ObjCImplementationDecl *classImpl,
2061                               const ObjCPropertyImplDecl *propImpl,
2062                               llvm::Constant *AtomicHelperFn);
2063 
2064   //===--------------------------------------------------------------------===//
2065   //                                  Block Bits
2066   //===--------------------------------------------------------------------===//
2067 
2068   /// Emit block literal.
2069   /// \return an LLVM value which is a pointer to a struct which contains
2070   /// information about the block, including the block invoke function, the
2071   /// captured variables, etc.
2072   llvm::Value *EmitBlockLiteral(const BlockExpr *);
2073 
2074   llvm::Function *GenerateBlockFunction(GlobalDecl GD,
2075                                         const CGBlockInfo &Info,
2076                                         const DeclMapTy &ldm,
2077                                         bool IsLambdaConversionToBlock,
2078                                         bool BuildGlobalBlock);
2079 
2080   /// Check if \p T is a C++ class that has a destructor that can throw.
2081   static bool cxxDestructorCanThrow(QualType T);
2082 
2083   llvm::Constant *GenerateCopyHelperFunction(const CGBlockInfo &blockInfo);
2084   llvm::Constant *GenerateDestroyHelperFunction(const CGBlockInfo &blockInfo);
2085   llvm::Constant *GenerateObjCAtomicSetterCopyHelperFunction(
2086                                              const ObjCPropertyImplDecl *PID);
2087   llvm::Constant *GenerateObjCAtomicGetterCopyHelperFunction(
2088                                              const ObjCPropertyImplDecl *PID);
2089   llvm::Value *EmitBlockCopyAndAutorelease(llvm::Value *Block, QualType Ty);
2090 
2091   void BuildBlockRelease(llvm::Value *DeclPtr, BlockFieldFlags flags,
2092                          bool CanThrow);
2093 
2094   class AutoVarEmission;
2095 
2096   void emitByrefStructureInit(const AutoVarEmission &emission);
2097 
2098   /// Enter a cleanup to destroy a __block variable.  Note that this
2099   /// cleanup should be a no-op if the variable hasn't left the stack
2100   /// yet; if a cleanup is required for the variable itself, that needs
2101   /// to be done externally.
2102   ///
2103   /// \param Kind Cleanup kind.
2104   ///
2105   /// \param Addr When \p LoadBlockVarAddr is false, the address of the __block
2106   /// structure that will be passed to _Block_object_dispose. When
2107   /// \p LoadBlockVarAddr is true, the address of the field of the block
2108   /// structure that holds the address of the __block structure.
2109   ///
2110   /// \param Flags The flag that will be passed to _Block_object_dispose.
2111   ///
2112   /// \param LoadBlockVarAddr Indicates whether we need to emit a load from
2113   /// \p Addr to get the address of the __block structure.
2114   void enterByrefCleanup(CleanupKind Kind, Address Addr, BlockFieldFlags Flags,
2115                          bool LoadBlockVarAddr, bool CanThrow);
2116 
2117   void setBlockContextParameter(const ImplicitParamDecl *D, unsigned argNum,
2118                                 llvm::Value *ptr);
2119 
2120   Address LoadBlockStruct();
2121   Address GetAddrOfBlockDecl(const VarDecl *var);
2122 
2123   /// BuildBlockByrefAddress - Computes the location of the
2124   /// data in a variable which is declared as __block.
2125   Address emitBlockByrefAddress(Address baseAddr, const VarDecl *V,
2126                                 bool followForward = true);
2127   Address emitBlockByrefAddress(Address baseAddr,
2128                                 const BlockByrefInfo &info,
2129                                 bool followForward,
2130                                 const llvm::Twine &name);
2131 
2132   const BlockByrefInfo &getBlockByrefInfo(const VarDecl *var);
2133 
2134   QualType BuildFunctionArgList(GlobalDecl GD, FunctionArgList &Args);
2135 
2136   void GenerateCode(GlobalDecl GD, llvm::Function *Fn,
2137                     const CGFunctionInfo &FnInfo);
2138 
2139   /// Annotate the function with an attribute that disables TSan checking at
2140   /// runtime.
2141   void markAsIgnoreThreadCheckingAtRuntime(llvm::Function *Fn);
2142 
2143   /// Emit code for the start of a function.
2144   /// \param Loc       The location to be associated with the function.
2145   /// \param StartLoc  The location of the function body.
2146   void StartFunction(GlobalDecl GD,
2147                      QualType RetTy,
2148                      llvm::Function *Fn,
2149                      const CGFunctionInfo &FnInfo,
2150                      const FunctionArgList &Args,
2151                      SourceLocation Loc = SourceLocation(),
2152                      SourceLocation StartLoc = SourceLocation());
2153 
2154   static bool IsConstructorDelegationValid(const CXXConstructorDecl *Ctor);
2155 
2156   void EmitConstructorBody(FunctionArgList &Args);
2157   void EmitDestructorBody(FunctionArgList &Args);
2158   void emitImplicitAssignmentOperatorBody(FunctionArgList &Args);
2159   void EmitFunctionBody(const Stmt *Body);
2160   void EmitBlockWithFallThrough(llvm::BasicBlock *BB, const Stmt *S);
2161 
2162   void EmitForwardingCallToLambda(const CXXMethodDecl *LambdaCallOperator,
2163                                   CallArgList &CallArgs);
2164   void EmitLambdaBlockInvokeBody();
2165   void EmitLambdaDelegatingInvokeBody(const CXXMethodDecl *MD);
2166   void EmitLambdaStaticInvokeBody(const CXXMethodDecl *MD);
2167   void EmitLambdaVLACapture(const VariableArrayType *VAT, LValue LV) {
2168     EmitStoreThroughLValue(RValue::get(VLASizeMap[VAT->getSizeExpr()]), LV);
2169   }
2170   void EmitAsanPrologueOrEpilogue(bool Prologue);
2171 
2172   /// Emit the unified return block, trying to avoid its emission when
2173   /// possible.
2174   /// \return The debug location of the user written return statement if the
2175   /// return block is is avoided.
2176   llvm::DebugLoc EmitReturnBlock();
2177 
2178   /// FinishFunction - Complete IR generation of the current function. It is
2179   /// legal to call this function even if there is no current insertion point.
2180   void FinishFunction(SourceLocation EndLoc=SourceLocation());
2181 
2182   void StartThunk(llvm::Function *Fn, GlobalDecl GD,
2183                   const CGFunctionInfo &FnInfo, bool IsUnprototyped);
2184 
2185   void EmitCallAndReturnForThunk(llvm::FunctionCallee Callee,
2186                                  const ThunkInfo *Thunk, bool IsUnprototyped);
2187 
2188   void FinishThunk();
2189 
2190   /// Emit a musttail call for a thunk with a potentially adjusted this pointer.
2191   void EmitMustTailThunk(GlobalDecl GD, llvm::Value *AdjustedThisPtr,
2192                          llvm::FunctionCallee Callee);
2193 
2194   /// Generate a thunk for the given method.
2195   void generateThunk(llvm::Function *Fn, const CGFunctionInfo &FnInfo,
2196                      GlobalDecl GD, const ThunkInfo &Thunk,
2197                      bool IsUnprototyped);
2198 
2199   llvm::Function *GenerateVarArgsThunk(llvm::Function *Fn,
2200                                        const CGFunctionInfo &FnInfo,
2201                                        GlobalDecl GD, const ThunkInfo &Thunk);
2202 
2203   void EmitCtorPrologue(const CXXConstructorDecl *CD, CXXCtorType Type,
2204                         FunctionArgList &Args);
2205 
2206   void EmitInitializerForField(FieldDecl *Field, LValue LHS, Expr *Init);
2207 
2208   /// Struct with all information about dynamic [sub]class needed to set vptr.
2209   struct VPtr {
2210     BaseSubobject Base;
2211     const CXXRecordDecl *NearestVBase;
2212     CharUnits OffsetFromNearestVBase;
2213     const CXXRecordDecl *VTableClass;
2214   };
2215 
2216   /// Initialize the vtable pointer of the given subobject.
2217   void InitializeVTablePointer(const VPtr &vptr);
2218 
2219   typedef llvm::SmallVector<VPtr, 4> VPtrsVector;
2220 
2221   typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
2222   VPtrsVector getVTablePointers(const CXXRecordDecl *VTableClass);
2223 
2224   void getVTablePointers(BaseSubobject Base, const CXXRecordDecl *NearestVBase,
2225                          CharUnits OffsetFromNearestVBase,
2226                          bool BaseIsNonVirtualPrimaryBase,
2227                          const CXXRecordDecl *VTableClass,
2228                          VisitedVirtualBasesSetTy &VBases, VPtrsVector &vptrs);
2229 
2230   void InitializeVTablePointers(const CXXRecordDecl *ClassDecl);
2231 
2232   /// GetVTablePtr - Return the Value of the vtable pointer member pointed
2233   /// to by This.
2234   llvm::Value *GetVTablePtr(Address This, llvm::Type *VTableTy,
2235                             const CXXRecordDecl *VTableClass);
2236 
2237   enum CFITypeCheckKind {
2238     CFITCK_VCall,
2239     CFITCK_NVCall,
2240     CFITCK_DerivedCast,
2241     CFITCK_UnrelatedCast,
2242     CFITCK_ICall,
2243     CFITCK_NVMFCall,
2244     CFITCK_VMFCall,
2245   };
2246 
2247   /// Derived is the presumed address of an object of type T after a
2248   /// cast. If T is a polymorphic class type, emit a check that the virtual
2249   /// table for Derived belongs to a class derived from T.
2250   void EmitVTablePtrCheckForCast(QualType T, llvm::Value *Derived,
2251                                  bool MayBeNull, CFITypeCheckKind TCK,
2252                                  SourceLocation Loc);
2253 
2254   /// EmitVTablePtrCheckForCall - Virtual method MD is being called via VTable.
2255   /// If vptr CFI is enabled, emit a check that VTable is valid.
2256   void EmitVTablePtrCheckForCall(const CXXRecordDecl *RD, llvm::Value *VTable,
2257                                  CFITypeCheckKind TCK, SourceLocation Loc);
2258 
2259   /// EmitVTablePtrCheck - Emit a check that VTable is a valid virtual table for
2260   /// RD using llvm.type.test.
2261   void EmitVTablePtrCheck(const CXXRecordDecl *RD, llvm::Value *VTable,
2262                           CFITypeCheckKind TCK, SourceLocation Loc);
2263 
2264   /// If whole-program virtual table optimization is enabled, emit an assumption
2265   /// that VTable is a member of RD's type identifier. Or, if vptr CFI is
2266   /// enabled, emit a check that VTable is a member of RD's type identifier.
2267   void EmitTypeMetadataCodeForVCall(const CXXRecordDecl *RD,
2268                                     llvm::Value *VTable, SourceLocation Loc);
2269 
2270   /// Returns whether we should perform a type checked load when loading a
2271   /// virtual function for virtual calls to members of RD. This is generally
2272   /// true when both vcall CFI and whole-program-vtables are enabled.
2273   bool ShouldEmitVTableTypeCheckedLoad(const CXXRecordDecl *RD);
2274 
2275   /// Emit a type checked load from the given vtable.
2276   llvm::Value *EmitVTableTypeCheckedLoad(const CXXRecordDecl *RD, llvm::Value *VTable,
2277                                          uint64_t VTableByteOffset);
2278 
2279   /// EnterDtorCleanups - Enter the cleanups necessary to complete the
2280   /// given phase of destruction for a destructor.  The end result
2281   /// should call destructors on members and base classes in reverse
2282   /// order of their construction.
2283   void EnterDtorCleanups(const CXXDestructorDecl *Dtor, CXXDtorType Type);
2284 
2285   /// ShouldInstrumentFunction - Return true if the current function should be
2286   /// instrumented with __cyg_profile_func_* calls
2287   bool ShouldInstrumentFunction();
2288 
2289   /// ShouldSkipSanitizerInstrumentation - Return true if the current function
2290   /// should not be instrumented with sanitizers.
2291   bool ShouldSkipSanitizerInstrumentation();
2292 
2293   /// ShouldXRayInstrument - Return true if the current function should be
2294   /// instrumented with XRay nop sleds.
2295   bool ShouldXRayInstrumentFunction() const;
2296 
2297   /// AlwaysEmitXRayCustomEvents - Return true if we must unconditionally emit
2298   /// XRay custom event handling calls.
2299   bool AlwaysEmitXRayCustomEvents() const;
2300 
2301   /// AlwaysEmitXRayTypedEvents - Return true if clang must unconditionally emit
2302   /// XRay typed event handling calls.
2303   bool AlwaysEmitXRayTypedEvents() const;
2304 
2305   /// Encode an address into a form suitable for use in a function prologue.
2306   llvm::Constant *EncodeAddrForUseInPrologue(llvm::Function *F,
2307                                              llvm::Constant *Addr);
2308 
2309   /// Decode an address used in a function prologue, encoded by \c
2310   /// EncodeAddrForUseInPrologue.
2311   llvm::Value *DecodeAddrUsedInPrologue(llvm::Value *F,
2312                                         llvm::Value *EncodedAddr);
2313 
2314   /// EmitFunctionProlog - Emit the target specific LLVM code to load the
2315   /// arguments for the given function. This is also responsible for naming the
2316   /// LLVM function arguments.
2317   void EmitFunctionProlog(const CGFunctionInfo &FI,
2318                           llvm::Function *Fn,
2319                           const FunctionArgList &Args);
2320 
2321   /// EmitFunctionEpilog - Emit the target specific LLVM code to return the
2322   /// given temporary.
2323   void EmitFunctionEpilog(const CGFunctionInfo &FI, bool EmitRetDbgLoc,
2324                           SourceLocation EndLoc);
2325 
2326   /// Emit a test that checks if the return value \p RV is nonnull.
2327   void EmitReturnValueCheck(llvm::Value *RV);
2328 
2329   /// EmitStartEHSpec - Emit the start of the exception spec.
2330   void EmitStartEHSpec(const Decl *D);
2331 
2332   /// EmitEndEHSpec - Emit the end of the exception spec.
2333   void EmitEndEHSpec(const Decl *D);
2334 
2335   /// getTerminateLandingPad - Return a landing pad that just calls terminate.
2336   llvm::BasicBlock *getTerminateLandingPad();
2337 
2338   /// getTerminateLandingPad - Return a cleanup funclet that just calls
2339   /// terminate.
2340   llvm::BasicBlock *getTerminateFunclet();
2341 
2342   /// getTerminateHandler - Return a handler (not a landing pad, just
2343   /// a catch handler) that just calls terminate.  This is used when
2344   /// a terminate scope encloses a try.
2345   llvm::BasicBlock *getTerminateHandler();
2346 
2347   llvm::Type *ConvertTypeForMem(QualType T);
2348   llvm::Type *ConvertType(QualType T);
2349   llvm::Type *ConvertType(const TypeDecl *T) {
2350     return ConvertType(getContext().getTypeDeclType(T));
2351   }
2352 
2353   /// LoadObjCSelf - Load the value of self. This function is only valid while
2354   /// generating code for an Objective-C method.
2355   llvm::Value *LoadObjCSelf();
2356 
2357   /// TypeOfSelfObject - Return type of object that this self represents.
2358   QualType TypeOfSelfObject();
2359 
2360   /// getEvaluationKind - Return the TypeEvaluationKind of QualType \c T.
2361   static TypeEvaluationKind getEvaluationKind(QualType T);
2362 
2363   static bool hasScalarEvaluationKind(QualType T) {
2364     return getEvaluationKind(T) == TEK_Scalar;
2365   }
2366 
2367   static bool hasAggregateEvaluationKind(QualType T) {
2368     return getEvaluationKind(T) == TEK_Aggregate;
2369   }
2370 
2371   /// createBasicBlock - Create an LLVM basic block.
2372   llvm::BasicBlock *createBasicBlock(const Twine &name = "",
2373                                      llvm::Function *parent = nullptr,
2374                                      llvm::BasicBlock *before = nullptr) {
2375     return llvm::BasicBlock::Create(getLLVMContext(), name, parent, before);
2376   }
2377 
2378   /// getBasicBlockForLabel - Return the LLVM basicblock that the specified
2379   /// label maps to.
2380   JumpDest getJumpDestForLabel(const LabelDecl *S);
2381 
2382   /// SimplifyForwardingBlocks - If the given basic block is only a branch to
2383   /// another basic block, simplify it. This assumes that no other code could
2384   /// potentially reference the basic block.
2385   void SimplifyForwardingBlocks(llvm::BasicBlock *BB);
2386 
2387   /// EmitBlock - Emit the given block \arg BB and set it as the insert point,
2388   /// adding a fall-through branch from the current insert block if
2389   /// necessary. It is legal to call this function even if there is no current
2390   /// insertion point.
2391   ///
2392   /// IsFinished - If true, indicates that the caller has finished emitting
2393   /// branches to the given block and does not expect to emit code into it. This
2394   /// means the block can be ignored if it is unreachable.
2395   void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false);
2396 
2397   /// EmitBlockAfterUses - Emit the given block somewhere hopefully
2398   /// near its uses, and leave the insertion point in it.
2399   void EmitBlockAfterUses(llvm::BasicBlock *BB);
2400 
2401   /// EmitBranch - Emit a branch to the specified basic block from the current
2402   /// insert block, taking care to avoid creation of branches from dummy
2403   /// blocks. It is legal to call this function even if there is no current
2404   /// insertion point.
2405   ///
2406   /// This function clears the current insertion point. The caller should follow
2407   /// calls to this function with calls to Emit*Block prior to generation new
2408   /// code.
2409   void EmitBranch(llvm::BasicBlock *Block);
2410 
2411   /// HaveInsertPoint - True if an insertion point is defined. If not, this
2412   /// indicates that the current code being emitted is unreachable.
2413   bool HaveInsertPoint() const {
2414     return Builder.GetInsertBlock() != nullptr;
2415   }
2416 
2417   /// EnsureInsertPoint - Ensure that an insertion point is defined so that
2418   /// emitted IR has a place to go. Note that by definition, if this function
2419   /// creates a block then that block is unreachable; callers may do better to
2420   /// detect when no insertion point is defined and simply skip IR generation.
2421   void EnsureInsertPoint() {
2422     if (!HaveInsertPoint())
2423       EmitBlock(createBasicBlock());
2424   }
2425 
2426   /// ErrorUnsupported - Print out an error that codegen doesn't support the
2427   /// specified stmt yet.
2428   void ErrorUnsupported(const Stmt *S, const char *Type);
2429 
2430   //===--------------------------------------------------------------------===//
2431   //                                  Helpers
2432   //===--------------------------------------------------------------------===//
2433 
2434   LValue MakeAddrLValue(Address Addr, QualType T,
2435                         AlignmentSource Source = AlignmentSource::Type) {
2436     return LValue::MakeAddr(Addr, T, getContext(), LValueBaseInfo(Source),
2437                             CGM.getTBAAAccessInfo(T));
2438   }
2439 
2440   LValue MakeAddrLValue(Address Addr, QualType T, LValueBaseInfo BaseInfo,
2441                         TBAAAccessInfo TBAAInfo) {
2442     return LValue::MakeAddr(Addr, T, getContext(), BaseInfo, TBAAInfo);
2443   }
2444 
2445   LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment,
2446                         AlignmentSource Source = AlignmentSource::Type) {
2447     return LValue::MakeAddr(Address(V, Alignment), T, getContext(),
2448                             LValueBaseInfo(Source), CGM.getTBAAAccessInfo(T));
2449   }
2450 
2451   LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment,
2452                         LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo) {
2453     return LValue::MakeAddr(Address(V, Alignment), T, getContext(),
2454                             BaseInfo, TBAAInfo);
2455   }
2456 
2457   LValue MakeNaturalAlignPointeeAddrLValue(llvm::Value *V, QualType T);
2458   LValue MakeNaturalAlignAddrLValue(llvm::Value *V, QualType T);
2459 
2460   Address EmitLoadOfReference(LValue RefLVal,
2461                               LValueBaseInfo *PointeeBaseInfo = nullptr,
2462                               TBAAAccessInfo *PointeeTBAAInfo = nullptr);
2463   LValue EmitLoadOfReferenceLValue(LValue RefLVal);
2464   LValue EmitLoadOfReferenceLValue(Address RefAddr, QualType RefTy,
2465                                    AlignmentSource Source =
2466                                        AlignmentSource::Type) {
2467     LValue RefLVal = MakeAddrLValue(RefAddr, RefTy, LValueBaseInfo(Source),
2468                                     CGM.getTBAAAccessInfo(RefTy));
2469     return EmitLoadOfReferenceLValue(RefLVal);
2470   }
2471 
2472   Address EmitLoadOfPointer(Address Ptr, const PointerType *PtrTy,
2473                             LValueBaseInfo *BaseInfo = nullptr,
2474                             TBAAAccessInfo *TBAAInfo = nullptr);
2475   LValue EmitLoadOfPointerLValue(Address Ptr, const PointerType *PtrTy);
2476 
2477   /// CreateTempAlloca - This creates an alloca and inserts it into the entry
2478   /// block if \p ArraySize is nullptr, otherwise inserts it at the current
2479   /// insertion point of the builder. The caller is responsible for setting an
2480   /// appropriate alignment on
2481   /// the alloca.
2482   ///
2483   /// \p ArraySize is the number of array elements to be allocated if it
2484   ///    is not nullptr.
2485   ///
2486   /// LangAS::Default is the address space of pointers to local variables and
2487   /// temporaries, as exposed in the source language. In certain
2488   /// configurations, this is not the same as the alloca address space, and a
2489   /// cast is needed to lift the pointer from the alloca AS into
2490   /// LangAS::Default. This can happen when the target uses a restricted
2491   /// address space for the stack but the source language requires
2492   /// LangAS::Default to be a generic address space. The latter condition is
2493   /// common for most programming languages; OpenCL is an exception in that
2494   /// LangAS::Default is the private address space, which naturally maps
2495   /// to the stack.
2496   ///
2497   /// Because the address of a temporary is often exposed to the program in
2498   /// various ways, this function will perform the cast. The original alloca
2499   /// instruction is returned through \p Alloca if it is not nullptr.
2500   ///
2501   /// The cast is not performaed in CreateTempAllocaWithoutCast. This is
2502   /// more efficient if the caller knows that the address will not be exposed.
2503   llvm::AllocaInst *CreateTempAlloca(llvm::Type *Ty, const Twine &Name = "tmp",
2504                                      llvm::Value *ArraySize = nullptr);
2505   Address CreateTempAlloca(llvm::Type *Ty, CharUnits align,
2506                            const Twine &Name = "tmp",
2507                            llvm::Value *ArraySize = nullptr,
2508                            Address *Alloca = nullptr);
2509   Address CreateTempAllocaWithoutCast(llvm::Type *Ty, CharUnits align,
2510                                       const Twine &Name = "tmp",
2511                                       llvm::Value *ArraySize = nullptr);
2512 
2513   /// CreateDefaultAlignedTempAlloca - This creates an alloca with the
2514   /// default ABI alignment of the given LLVM type.
2515   ///
2516   /// IMPORTANT NOTE: This is *not* generally the right alignment for
2517   /// any given AST type that happens to have been lowered to the
2518   /// given IR type.  This should only ever be used for function-local,
2519   /// IR-driven manipulations like saving and restoring a value.  Do
2520   /// not hand this address off to arbitrary IRGen routines, and especially
2521   /// do not pass it as an argument to a function that might expect a
2522   /// properly ABI-aligned value.
2523   Address CreateDefaultAlignTempAlloca(llvm::Type *Ty,
2524                                        const Twine &Name = "tmp");
2525 
2526   /// InitTempAlloca - Provide an initial value for the given alloca which
2527   /// will be observable at all locations in the function.
2528   ///
2529   /// The address should be something that was returned from one of
2530   /// the CreateTempAlloca or CreateMemTemp routines, and the
2531   /// initializer must be valid in the entry block (i.e. it must
2532   /// either be a constant or an argument value).
2533   void InitTempAlloca(Address Alloca, llvm::Value *Value);
2534 
2535   /// CreateIRTemp - Create a temporary IR object of the given type, with
2536   /// appropriate alignment. This routine should only be used when an temporary
2537   /// value needs to be stored into an alloca (for example, to avoid explicit
2538   /// PHI construction), but the type is the IR type, not the type appropriate
2539   /// for storing in memory.
2540   ///
2541   /// That is, this is exactly equivalent to CreateMemTemp, but calling
2542   /// ConvertType instead of ConvertTypeForMem.
2543   Address CreateIRTemp(QualType T, const Twine &Name = "tmp");
2544 
2545   /// CreateMemTemp - Create a temporary memory object of the given type, with
2546   /// appropriate alignmen and cast it to the default address space. Returns
2547   /// the original alloca instruction by \p Alloca if it is not nullptr.
2548   Address CreateMemTemp(QualType T, const Twine &Name = "tmp",
2549                         Address *Alloca = nullptr);
2550   Address CreateMemTemp(QualType T, CharUnits Align, const Twine &Name = "tmp",
2551                         Address *Alloca = nullptr);
2552 
2553   /// CreateMemTemp - Create a temporary memory object of the given type, with
2554   /// appropriate alignmen without casting it to the default address space.
2555   Address CreateMemTempWithoutCast(QualType T, const Twine &Name = "tmp");
2556   Address CreateMemTempWithoutCast(QualType T, CharUnits Align,
2557                                    const Twine &Name = "tmp");
2558 
2559   /// CreateAggTemp - Create a temporary memory object for the given
2560   /// aggregate type.
2561   AggValueSlot CreateAggTemp(QualType T, const Twine &Name = "tmp",
2562                              Address *Alloca = nullptr) {
2563     return AggValueSlot::forAddr(CreateMemTemp(T, Name, Alloca),
2564                                  T.getQualifiers(),
2565                                  AggValueSlot::IsNotDestructed,
2566                                  AggValueSlot::DoesNotNeedGCBarriers,
2567                                  AggValueSlot::IsNotAliased,
2568                                  AggValueSlot::DoesNotOverlap);
2569   }
2570 
2571   /// Emit a cast to void* in the appropriate address space.
2572   llvm::Value *EmitCastToVoidPtr(llvm::Value *value);
2573 
2574   /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
2575   /// expression and compare the result against zero, returning an Int1Ty value.
2576   llvm::Value *EvaluateExprAsBool(const Expr *E);
2577 
2578   /// EmitIgnoredExpr - Emit an expression in a context which ignores the result.
2579   void EmitIgnoredExpr(const Expr *E);
2580 
2581   /// EmitAnyExpr - Emit code to compute the specified expression which can have
2582   /// any type.  The result is returned as an RValue struct.  If this is an
2583   /// aggregate expression, the aggloc/agglocvolatile arguments indicate where
2584   /// the result should be returned.
2585   ///
2586   /// \param ignoreResult True if the resulting value isn't used.
2587   RValue EmitAnyExpr(const Expr *E,
2588                      AggValueSlot aggSlot = AggValueSlot::ignored(),
2589                      bool ignoreResult = false);
2590 
2591   // EmitVAListRef - Emit a "reference" to a va_list; this is either the address
2592   // or the value of the expression, depending on how va_list is defined.
2593   Address EmitVAListRef(const Expr *E);
2594 
2595   /// Emit a "reference" to a __builtin_ms_va_list; this is
2596   /// always the value of the expression, because a __builtin_ms_va_list is a
2597   /// pointer to a char.
2598   Address EmitMSVAListRef(const Expr *E);
2599 
2600   /// EmitAnyExprToTemp - Similarly to EmitAnyExpr(), however, the result will
2601   /// always be accessible even if no aggregate location is provided.
2602   RValue EmitAnyExprToTemp(const Expr *E);
2603 
2604   /// EmitAnyExprToMem - Emits the code necessary to evaluate an
2605   /// arbitrary expression into the given memory location.
2606   void EmitAnyExprToMem(const Expr *E, Address Location,
2607                         Qualifiers Quals, bool IsInitializer);
2608 
2609   void EmitAnyExprToExn(const Expr *E, Address Addr);
2610 
2611   /// EmitExprAsInit - Emits the code necessary to initialize a
2612   /// location in memory with the given initializer.
2613   void EmitExprAsInit(const Expr *init, const ValueDecl *D, LValue lvalue,
2614                       bool capturedByInit);
2615 
2616   /// hasVolatileMember - returns true if aggregate type has a volatile
2617   /// member.
2618   bool hasVolatileMember(QualType T) {
2619     if (const RecordType *RT = T->getAs<RecordType>()) {
2620       const RecordDecl *RD = cast<RecordDecl>(RT->getDecl());
2621       return RD->hasVolatileMember();
2622     }
2623     return false;
2624   }
2625 
2626   /// Determine whether a return value slot may overlap some other object.
2627   AggValueSlot::Overlap_t getOverlapForReturnValue() {
2628     // FIXME: Assuming no overlap here breaks guaranteed copy elision for base
2629     // class subobjects. These cases may need to be revisited depending on the
2630     // resolution of the relevant core issue.
2631     return AggValueSlot::DoesNotOverlap;
2632   }
2633 
2634   /// Determine whether a field initialization may overlap some other object.
2635   AggValueSlot::Overlap_t getOverlapForFieldInit(const FieldDecl *FD);
2636 
2637   /// Determine whether a base class initialization may overlap some other
2638   /// object.
2639   AggValueSlot::Overlap_t getOverlapForBaseInit(const CXXRecordDecl *RD,
2640                                                 const CXXRecordDecl *BaseRD,
2641                                                 bool IsVirtual);
2642 
2643   /// Emit an aggregate assignment.
2644   void EmitAggregateAssign(LValue Dest, LValue Src, QualType EltTy) {
2645     bool IsVolatile = hasVolatileMember(EltTy);
2646     EmitAggregateCopy(Dest, Src, EltTy, AggValueSlot::MayOverlap, IsVolatile);
2647   }
2648 
2649   void EmitAggregateCopyCtor(LValue Dest, LValue Src,
2650                              AggValueSlot::Overlap_t MayOverlap) {
2651     EmitAggregateCopy(Dest, Src, Src.getType(), MayOverlap);
2652   }
2653 
2654   /// EmitAggregateCopy - Emit an aggregate copy.
2655   ///
2656   /// \param isVolatile \c true iff either the source or the destination is
2657   ///        volatile.
2658   /// \param MayOverlap Whether the tail padding of the destination might be
2659   ///        occupied by some other object. More efficient code can often be
2660   ///        generated if not.
2661   void EmitAggregateCopy(LValue Dest, LValue Src, QualType EltTy,
2662                          AggValueSlot::Overlap_t MayOverlap,
2663                          bool isVolatile = false);
2664 
2665   /// GetAddrOfLocalVar - Return the address of a local variable.
2666   Address GetAddrOfLocalVar(const VarDecl *VD) {
2667     auto it = LocalDeclMap.find(VD);
2668     assert(it != LocalDeclMap.end() &&
2669            "Invalid argument to GetAddrOfLocalVar(), no decl!");
2670     return it->second;
2671   }
2672 
2673   /// Given an opaque value expression, return its LValue mapping if it exists,
2674   /// otherwise create one.
2675   LValue getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e);
2676 
2677   /// Given an opaque value expression, return its RValue mapping if it exists,
2678   /// otherwise create one.
2679   RValue getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e);
2680 
2681   /// Get the index of the current ArrayInitLoopExpr, if any.
2682   llvm::Value *getArrayInitIndex() { return ArrayInitIndex; }
2683 
2684   /// getAccessedFieldNo - Given an encoded value and a result number, return
2685   /// the input field number being accessed.
2686   static unsigned getAccessedFieldNo(unsigned Idx, const llvm::Constant *Elts);
2687 
2688   llvm::BlockAddress *GetAddrOfLabel(const LabelDecl *L);
2689   llvm::BasicBlock *GetIndirectGotoBlock();
2690 
2691   /// Check if \p E is a C++ "this" pointer wrapped in value-preserving casts.
2692   static bool IsWrappedCXXThis(const Expr *E);
2693 
2694   /// EmitNullInitialization - Generate code to set a value of the given type to
2695   /// null, If the type contains data member pointers, they will be initialized
2696   /// to -1 in accordance with the Itanium C++ ABI.
2697   void EmitNullInitialization(Address DestPtr, QualType Ty);
2698 
2699   /// Emits a call to an LLVM variable-argument intrinsic, either
2700   /// \c llvm.va_start or \c llvm.va_end.
2701   /// \param ArgValue A reference to the \c va_list as emitted by either
2702   /// \c EmitVAListRef or \c EmitMSVAListRef.
2703   /// \param IsStart If \c true, emits a call to \c llvm.va_start; otherwise,
2704   /// calls \c llvm.va_end.
2705   llvm::Value *EmitVAStartEnd(llvm::Value *ArgValue, bool IsStart);
2706 
2707   /// Generate code to get an argument from the passed in pointer
2708   /// and update it accordingly.
2709   /// \param VE The \c VAArgExpr for which to generate code.
2710   /// \param VAListAddr Receives a reference to the \c va_list as emitted by
2711   /// either \c EmitVAListRef or \c EmitMSVAListRef.
2712   /// \returns A pointer to the argument.
2713   // FIXME: We should be able to get rid of this method and use the va_arg
2714   // instruction in LLVM instead once it works well enough.
2715   Address EmitVAArg(VAArgExpr *VE, Address &VAListAddr);
2716 
2717   /// emitArrayLength - Compute the length of an array, even if it's a
2718   /// VLA, and drill down to the base element type.
2719   llvm::Value *emitArrayLength(const ArrayType *arrayType,
2720                                QualType &baseType,
2721                                Address &addr);
2722 
2723   /// EmitVLASize - Capture all the sizes for the VLA expressions in
2724   /// the given variably-modified type and store them in the VLASizeMap.
2725   ///
2726   /// This function can be called with a null (unreachable) insert point.
2727   void EmitVariablyModifiedType(QualType Ty);
2728 
2729   struct VlaSizePair {
2730     llvm::Value *NumElts;
2731     QualType Type;
2732 
2733     VlaSizePair(llvm::Value *NE, QualType T) : NumElts(NE), Type(T) {}
2734   };
2735 
2736   /// Return the number of elements for a single dimension
2737   /// for the given array type.
2738   VlaSizePair getVLAElements1D(const VariableArrayType *vla);
2739   VlaSizePair getVLAElements1D(QualType vla);
2740 
2741   /// Returns an LLVM value that corresponds to the size,
2742   /// in non-variably-sized elements, of a variable length array type,
2743   /// plus that largest non-variably-sized element type.  Assumes that
2744   /// the type has already been emitted with EmitVariablyModifiedType.
2745   VlaSizePair getVLASize(const VariableArrayType *vla);
2746   VlaSizePair getVLASize(QualType vla);
2747 
2748   /// LoadCXXThis - Load the value of 'this'. This function is only valid while
2749   /// generating code for an C++ member function.
2750   llvm::Value *LoadCXXThis() {
2751     assert(CXXThisValue && "no 'this' value for this function");
2752     return CXXThisValue;
2753   }
2754   Address LoadCXXThisAddress();
2755 
2756   /// LoadCXXVTT - Load the VTT parameter to base constructors/destructors have
2757   /// virtual bases.
2758   // FIXME: Every place that calls LoadCXXVTT is something
2759   // that needs to be abstracted properly.
2760   llvm::Value *LoadCXXVTT() {
2761     assert(CXXStructorImplicitParamValue && "no VTT value for this function");
2762     return CXXStructorImplicitParamValue;
2763   }
2764 
2765   /// GetAddressOfBaseOfCompleteClass - Convert the given pointer to a
2766   /// complete class to the given direct base.
2767   Address
2768   GetAddressOfDirectBaseInCompleteClass(Address Value,
2769                                         const CXXRecordDecl *Derived,
2770                                         const CXXRecordDecl *Base,
2771                                         bool BaseIsVirtual);
2772 
2773   static bool ShouldNullCheckClassCastValue(const CastExpr *Cast);
2774 
2775   /// GetAddressOfBaseClass - This function will add the necessary delta to the
2776   /// load of 'this' and returns address of the base class.
2777   Address GetAddressOfBaseClass(Address Value,
2778                                 const CXXRecordDecl *Derived,
2779                                 CastExpr::path_const_iterator PathBegin,
2780                                 CastExpr::path_const_iterator PathEnd,
2781                                 bool NullCheckValue, SourceLocation Loc);
2782 
2783   Address GetAddressOfDerivedClass(Address Value,
2784                                    const CXXRecordDecl *Derived,
2785                                    CastExpr::path_const_iterator PathBegin,
2786                                    CastExpr::path_const_iterator PathEnd,
2787                                    bool NullCheckValue);
2788 
2789   /// GetVTTParameter - Return the VTT parameter that should be passed to a
2790   /// base constructor/destructor with virtual bases.
2791   /// FIXME: VTTs are Itanium ABI-specific, so the definition should move
2792   /// to ItaniumCXXABI.cpp together with all the references to VTT.
2793   llvm::Value *GetVTTParameter(GlobalDecl GD, bool ForVirtualBase,
2794                                bool Delegating);
2795 
2796   void EmitDelegateCXXConstructorCall(const CXXConstructorDecl *Ctor,
2797                                       CXXCtorType CtorType,
2798                                       const FunctionArgList &Args,
2799                                       SourceLocation Loc);
2800   // It's important not to confuse this and the previous function. Delegating
2801   // constructors are the C++0x feature. The constructor delegate optimization
2802   // is used to reduce duplication in the base and complete consturctors where
2803   // they are substantially the same.
2804   void EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor,
2805                                         const FunctionArgList &Args);
2806 
2807   /// Emit a call to an inheriting constructor (that is, one that invokes a
2808   /// constructor inherited from a base class) by inlining its definition. This
2809   /// is necessary if the ABI does not support forwarding the arguments to the
2810   /// base class constructor (because they're variadic or similar).
2811   void EmitInlinedInheritingCXXConstructorCall(const CXXConstructorDecl *Ctor,
2812                                                CXXCtorType CtorType,
2813                                                bool ForVirtualBase,
2814                                                bool Delegating,
2815                                                CallArgList &Args);
2816 
2817   /// Emit a call to a constructor inherited from a base class, passing the
2818   /// current constructor's arguments along unmodified (without even making
2819   /// a copy).
2820   void EmitInheritedCXXConstructorCall(const CXXConstructorDecl *D,
2821                                        bool ForVirtualBase, Address This,
2822                                        bool InheritedFromVBase,
2823                                        const CXXInheritedCtorInitExpr *E);
2824 
2825   void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
2826                               bool ForVirtualBase, bool Delegating,
2827                               AggValueSlot ThisAVS, const CXXConstructExpr *E);
2828 
2829   void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
2830                               bool ForVirtualBase, bool Delegating,
2831                               Address This, CallArgList &Args,
2832                               AggValueSlot::Overlap_t Overlap,
2833                               SourceLocation Loc, bool NewPointerIsChecked);
2834 
2835   /// Emit assumption load for all bases. Requires to be be called only on
2836   /// most-derived class and not under construction of the object.
2837   void EmitVTableAssumptionLoads(const CXXRecordDecl *ClassDecl, Address This);
2838 
2839   /// Emit assumption that vptr load == global vtable.
2840   void EmitVTableAssumptionLoad(const VPtr &vptr, Address This);
2841 
2842   void EmitSynthesizedCXXCopyCtorCall(const CXXConstructorDecl *D,
2843                                       Address This, Address Src,
2844                                       const CXXConstructExpr *E);
2845 
2846   void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
2847                                   const ArrayType *ArrayTy,
2848                                   Address ArrayPtr,
2849                                   const CXXConstructExpr *E,
2850                                   bool NewPointerIsChecked,
2851                                   bool ZeroInitialization = false);
2852 
2853   void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
2854                                   llvm::Value *NumElements,
2855                                   Address ArrayPtr,
2856                                   const CXXConstructExpr *E,
2857                                   bool NewPointerIsChecked,
2858                                   bool ZeroInitialization = false);
2859 
2860   static Destroyer destroyCXXObject;
2861 
2862   void EmitCXXDestructorCall(const CXXDestructorDecl *D, CXXDtorType Type,
2863                              bool ForVirtualBase, bool Delegating, Address This,
2864                              QualType ThisTy);
2865 
2866   void EmitNewArrayInitializer(const CXXNewExpr *E, QualType elementType,
2867                                llvm::Type *ElementTy, Address NewPtr,
2868                                llvm::Value *NumElements,
2869                                llvm::Value *AllocSizeWithoutCookie);
2870 
2871   void EmitCXXTemporary(const CXXTemporary *Temporary, QualType TempType,
2872                         Address Ptr);
2873 
2874   void EmitSehCppScopeBegin();
2875   void EmitSehCppScopeEnd();
2876   void EmitSehTryScopeBegin();
2877   void EmitSehTryScopeEnd();
2878 
2879   llvm::Value *EmitLifetimeStart(llvm::TypeSize Size, llvm::Value *Addr);
2880   void EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr);
2881 
2882   llvm::Value *EmitCXXNewExpr(const CXXNewExpr *E);
2883   void EmitCXXDeleteExpr(const CXXDeleteExpr *E);
2884 
2885   void EmitDeleteCall(const FunctionDecl *DeleteFD, llvm::Value *Ptr,
2886                       QualType DeleteTy, llvm::Value *NumElements = nullptr,
2887                       CharUnits CookieSize = CharUnits());
2888 
2889   RValue EmitBuiltinNewDeleteCall(const FunctionProtoType *Type,
2890                                   const CallExpr *TheCallExpr, bool IsDelete);
2891 
2892   llvm::Value *EmitCXXTypeidExpr(const CXXTypeidExpr *E);
2893   llvm::Value *EmitDynamicCast(Address V, const CXXDynamicCastExpr *DCE);
2894   Address EmitCXXUuidofExpr(const CXXUuidofExpr *E);
2895 
2896   /// Situations in which we might emit a check for the suitability of a
2897   /// pointer or glvalue. Needs to be kept in sync with ubsan_handlers.cpp in
2898   /// compiler-rt.
2899   enum TypeCheckKind {
2900     /// Checking the operand of a load. Must be suitably sized and aligned.
2901     TCK_Load,
2902     /// Checking the destination of a store. Must be suitably sized and aligned.
2903     TCK_Store,
2904     /// Checking the bound value in a reference binding. Must be suitably sized
2905     /// and aligned, but is not required to refer to an object (until the
2906     /// reference is used), per core issue 453.
2907     TCK_ReferenceBinding,
2908     /// Checking the object expression in a non-static data member access. Must
2909     /// be an object within its lifetime.
2910     TCK_MemberAccess,
2911     /// Checking the 'this' pointer for a call to a non-static member function.
2912     /// Must be an object within its lifetime.
2913     TCK_MemberCall,
2914     /// Checking the 'this' pointer for a constructor call.
2915     TCK_ConstructorCall,
2916     /// Checking the operand of a static_cast to a derived pointer type. Must be
2917     /// null or an object within its lifetime.
2918     TCK_DowncastPointer,
2919     /// Checking the operand of a static_cast to a derived reference type. Must
2920     /// be an object within its lifetime.
2921     TCK_DowncastReference,
2922     /// Checking the operand of a cast to a base object. Must be suitably sized
2923     /// and aligned.
2924     TCK_Upcast,
2925     /// Checking the operand of a cast to a virtual base object. Must be an
2926     /// object within its lifetime.
2927     TCK_UpcastToVirtualBase,
2928     /// Checking the value assigned to a _Nonnull pointer. Must not be null.
2929     TCK_NonnullAssign,
2930     /// Checking the operand of a dynamic_cast or a typeid expression.  Must be
2931     /// null or an object within its lifetime.
2932     TCK_DynamicOperation
2933   };
2934 
2935   /// Determine whether the pointer type check \p TCK permits null pointers.
2936   static bool isNullPointerAllowed(TypeCheckKind TCK);
2937 
2938   /// Determine whether the pointer type check \p TCK requires a vptr check.
2939   static bool isVptrCheckRequired(TypeCheckKind TCK, QualType Ty);
2940 
2941   /// Whether any type-checking sanitizers are enabled. If \c false,
2942   /// calls to EmitTypeCheck can be skipped.
2943   bool sanitizePerformTypeCheck() const;
2944 
2945   /// Emit a check that \p V is the address of storage of the
2946   /// appropriate size and alignment for an object of type \p Type
2947   /// (or if ArraySize is provided, for an array of that bound).
2948   void EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, llvm::Value *V,
2949                      QualType Type, CharUnits Alignment = CharUnits::Zero(),
2950                      SanitizerSet SkippedChecks = SanitizerSet(),
2951                      llvm::Value *ArraySize = nullptr);
2952 
2953   /// Emit a check that \p Base points into an array object, which
2954   /// we can access at index \p Index. \p Accessed should be \c false if we
2955   /// this expression is used as an lvalue, for instance in "&Arr[Idx]".
2956   void EmitBoundsCheck(const Expr *E, const Expr *Base, llvm::Value *Index,
2957                        QualType IndexType, bool Accessed);
2958 
2959   llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
2960                                        bool isInc, bool isPre);
2961   ComplexPairTy EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
2962                                          bool isInc, bool isPre);
2963 
2964   /// Converts Location to a DebugLoc, if debug information is enabled.
2965   llvm::DebugLoc SourceLocToDebugLoc(SourceLocation Location);
2966 
2967   /// Get the record field index as represented in debug info.
2968   unsigned getDebugInfoFIndex(const RecordDecl *Rec, unsigned FieldIndex);
2969 
2970 
2971   //===--------------------------------------------------------------------===//
2972   //                            Declaration Emission
2973   //===--------------------------------------------------------------------===//
2974 
2975   /// EmitDecl - Emit a declaration.
2976   ///
2977   /// This function can be called with a null (unreachable) insert point.
2978   void EmitDecl(const Decl &D);
2979 
2980   /// EmitVarDecl - Emit a local variable declaration.
2981   ///
2982   /// This function can be called with a null (unreachable) insert point.
2983   void EmitVarDecl(const VarDecl &D);
2984 
2985   void EmitScalarInit(const Expr *init, const ValueDecl *D, LValue lvalue,
2986                       bool capturedByInit);
2987 
2988   typedef void SpecialInitFn(CodeGenFunction &Init, const VarDecl &D,
2989                              llvm::Value *Address);
2990 
2991   /// Determine whether the given initializer is trivial in the sense
2992   /// that it requires no code to be generated.
2993   bool isTrivialInitializer(const Expr *Init);
2994 
2995   /// EmitAutoVarDecl - Emit an auto variable declaration.
2996   ///
2997   /// This function can be called with a null (unreachable) insert point.
2998   void EmitAutoVarDecl(const VarDecl &D);
2999 
3000   class AutoVarEmission {
3001     friend class CodeGenFunction;
3002 
3003     const VarDecl *Variable;
3004 
3005     /// The address of the alloca for languages with explicit address space
3006     /// (e.g. OpenCL) or alloca casted to generic pointer for address space
3007     /// agnostic languages (e.g. C++). Invalid if the variable was emitted
3008     /// as a global constant.
3009     Address Addr;
3010 
3011     llvm::Value *NRVOFlag;
3012 
3013     /// True if the variable is a __block variable that is captured by an
3014     /// escaping block.
3015     bool IsEscapingByRef;
3016 
3017     /// True if the variable is of aggregate type and has a constant
3018     /// initializer.
3019     bool IsConstantAggregate;
3020 
3021     /// Non-null if we should use lifetime annotations.
3022     llvm::Value *SizeForLifetimeMarkers;
3023 
3024     /// Address with original alloca instruction. Invalid if the variable was
3025     /// emitted as a global constant.
3026     Address AllocaAddr;
3027 
3028     struct Invalid {};
3029     AutoVarEmission(Invalid)
3030         : Variable(nullptr), Addr(Address::invalid()),
3031           AllocaAddr(Address::invalid()) {}
3032 
3033     AutoVarEmission(const VarDecl &variable)
3034         : Variable(&variable), Addr(Address::invalid()), NRVOFlag(nullptr),
3035           IsEscapingByRef(false), IsConstantAggregate(false),
3036           SizeForLifetimeMarkers(nullptr), AllocaAddr(Address::invalid()) {}
3037 
3038     bool wasEmittedAsGlobal() const { return !Addr.isValid(); }
3039 
3040   public:
3041     static AutoVarEmission invalid() { return AutoVarEmission(Invalid()); }
3042 
3043     bool useLifetimeMarkers() const {
3044       return SizeForLifetimeMarkers != nullptr;
3045     }
3046     llvm::Value *getSizeForLifetimeMarkers() const {
3047       assert(useLifetimeMarkers());
3048       return SizeForLifetimeMarkers;
3049     }
3050 
3051     /// Returns the raw, allocated address, which is not necessarily
3052     /// the address of the object itself. It is casted to default
3053     /// address space for address space agnostic languages.
3054     Address getAllocatedAddress() const {
3055       return Addr;
3056     }
3057 
3058     /// Returns the address for the original alloca instruction.
3059     Address getOriginalAllocatedAddress() const { return AllocaAddr; }
3060 
3061     /// Returns the address of the object within this declaration.
3062     /// Note that this does not chase the forwarding pointer for
3063     /// __block decls.
3064     Address getObjectAddress(CodeGenFunction &CGF) const {
3065       if (!IsEscapingByRef) return Addr;
3066 
3067       return CGF.emitBlockByrefAddress(Addr, Variable, /*forward*/ false);
3068     }
3069   };
3070   AutoVarEmission EmitAutoVarAlloca(const VarDecl &var);
3071   void EmitAutoVarInit(const AutoVarEmission &emission);
3072   void EmitAutoVarCleanups(const AutoVarEmission &emission);
3073   void emitAutoVarTypeCleanup(const AutoVarEmission &emission,
3074                               QualType::DestructionKind dtorKind);
3075 
3076   /// Emits the alloca and debug information for the size expressions for each
3077   /// dimension of an array. It registers the association of its (1-dimensional)
3078   /// QualTypes and size expression's debug node, so that CGDebugInfo can
3079   /// reference this node when creating the DISubrange object to describe the
3080   /// array types.
3081   void EmitAndRegisterVariableArrayDimensions(CGDebugInfo *DI,
3082                                               const VarDecl &D,
3083                                               bool EmitDebugInfo);
3084 
3085   void EmitStaticVarDecl(const VarDecl &D,
3086                          llvm::GlobalValue::LinkageTypes Linkage);
3087 
3088   class ParamValue {
3089     llvm::Value *Value;
3090     unsigned Alignment;
3091     ParamValue(llvm::Value *V, unsigned A) : Value(V), Alignment(A) {}
3092   public:
3093     static ParamValue forDirect(llvm::Value *value) {
3094       return ParamValue(value, 0);
3095     }
3096     static ParamValue forIndirect(Address addr) {
3097       assert(!addr.getAlignment().isZero());
3098       return ParamValue(addr.getPointer(), addr.getAlignment().getQuantity());
3099     }
3100 
3101     bool isIndirect() const { return Alignment != 0; }
3102     llvm::Value *getAnyValue() const { return Value; }
3103 
3104     llvm::Value *getDirectValue() const {
3105       assert(!isIndirect());
3106       return Value;
3107     }
3108 
3109     Address getIndirectAddress() const {
3110       assert(isIndirect());
3111       return Address(Value, CharUnits::fromQuantity(Alignment));
3112     }
3113   };
3114 
3115   /// EmitParmDecl - Emit a ParmVarDecl or an ImplicitParamDecl.
3116   void EmitParmDecl(const VarDecl &D, ParamValue Arg, unsigned ArgNo);
3117 
3118   /// protectFromPeepholes - Protect a value that we're intending to
3119   /// store to the side, but which will probably be used later, from
3120   /// aggressive peepholing optimizations that might delete it.
3121   ///
3122   /// Pass the result to unprotectFromPeepholes to declare that
3123   /// protection is no longer required.
3124   ///
3125   /// There's no particular reason why this shouldn't apply to
3126   /// l-values, it's just that no existing peepholes work on pointers.
3127   PeepholeProtection protectFromPeepholes(RValue rvalue);
3128   void unprotectFromPeepholes(PeepholeProtection protection);
3129 
3130   void emitAlignmentAssumptionCheck(llvm::Value *Ptr, QualType Ty,
3131                                     SourceLocation Loc,
3132                                     SourceLocation AssumptionLoc,
3133                                     llvm::Value *Alignment,
3134                                     llvm::Value *OffsetValue,
3135                                     llvm::Value *TheCheck,
3136                                     llvm::Instruction *Assumption);
3137 
3138   void emitAlignmentAssumption(llvm::Value *PtrValue, QualType Ty,
3139                                SourceLocation Loc, SourceLocation AssumptionLoc,
3140                                llvm::Value *Alignment,
3141                                llvm::Value *OffsetValue = nullptr);
3142 
3143   void emitAlignmentAssumption(llvm::Value *PtrValue, const Expr *E,
3144                                SourceLocation AssumptionLoc,
3145                                llvm::Value *Alignment,
3146                                llvm::Value *OffsetValue = nullptr);
3147 
3148   //===--------------------------------------------------------------------===//
3149   //                             Statement Emission
3150   //===--------------------------------------------------------------------===//
3151 
3152   /// EmitStopPoint - Emit a debug stoppoint if we are emitting debug info.
3153   void EmitStopPoint(const Stmt *S);
3154 
3155   /// EmitStmt - Emit the code for the statement \arg S. It is legal to call
3156   /// this function even if there is no current insertion point.
3157   ///
3158   /// This function may clear the current insertion point; callers should use
3159   /// EnsureInsertPoint if they wish to subsequently generate code without first
3160   /// calling EmitBlock, EmitBranch, or EmitStmt.
3161   void EmitStmt(const Stmt *S, ArrayRef<const Attr *> Attrs = None);
3162 
3163   /// EmitSimpleStmt - Try to emit a "simple" statement which does not
3164   /// necessarily require an insertion point or debug information; typically
3165   /// because the statement amounts to a jump or a container of other
3166   /// statements.
3167   ///
3168   /// \return True if the statement was handled.
3169   bool EmitSimpleStmt(const Stmt *S, ArrayRef<const Attr *> Attrs);
3170 
3171   Address EmitCompoundStmt(const CompoundStmt &S, bool GetLast = false,
3172                            AggValueSlot AVS = AggValueSlot::ignored());
3173   Address EmitCompoundStmtWithoutScope(const CompoundStmt &S,
3174                                        bool GetLast = false,
3175                                        AggValueSlot AVS =
3176                                                 AggValueSlot::ignored());
3177 
3178   /// EmitLabel - Emit the block for the given label. It is legal to call this
3179   /// function even if there is no current insertion point.
3180   void EmitLabel(const LabelDecl *D); // helper for EmitLabelStmt.
3181 
3182   void EmitLabelStmt(const LabelStmt &S);
3183   void EmitAttributedStmt(const AttributedStmt &S);
3184   void EmitGotoStmt(const GotoStmt &S);
3185   void EmitIndirectGotoStmt(const IndirectGotoStmt &S);
3186   void EmitIfStmt(const IfStmt &S);
3187 
3188   void EmitWhileStmt(const WhileStmt &S,
3189                      ArrayRef<const Attr *> Attrs = None);
3190   void EmitDoStmt(const DoStmt &S, ArrayRef<const Attr *> Attrs = None);
3191   void EmitForStmt(const ForStmt &S,
3192                    ArrayRef<const Attr *> Attrs = None);
3193   void EmitReturnStmt(const ReturnStmt &S);
3194   void EmitDeclStmt(const DeclStmt &S);
3195   void EmitBreakStmt(const BreakStmt &S);
3196   void EmitContinueStmt(const ContinueStmt &S);
3197   void EmitSwitchStmt(const SwitchStmt &S);
3198   void EmitDefaultStmt(const DefaultStmt &S, ArrayRef<const Attr *> Attrs);
3199   void EmitCaseStmt(const CaseStmt &S, ArrayRef<const Attr *> Attrs);
3200   void EmitCaseStmtRange(const CaseStmt &S, ArrayRef<const Attr *> Attrs);
3201   void EmitAsmStmt(const AsmStmt &S);
3202 
3203   void EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S);
3204   void EmitObjCAtTryStmt(const ObjCAtTryStmt &S);
3205   void EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S);
3206   void EmitObjCAtSynchronizedStmt(const ObjCAtSynchronizedStmt &S);
3207   void EmitObjCAutoreleasePoolStmt(const ObjCAutoreleasePoolStmt &S);
3208 
3209   void EmitCoroutineBody(const CoroutineBodyStmt &S);
3210   void EmitCoreturnStmt(const CoreturnStmt &S);
3211   RValue EmitCoawaitExpr(const CoawaitExpr &E,
3212                          AggValueSlot aggSlot = AggValueSlot::ignored(),
3213                          bool ignoreResult = false);
3214   LValue EmitCoawaitLValue(const CoawaitExpr *E);
3215   RValue EmitCoyieldExpr(const CoyieldExpr &E,
3216                          AggValueSlot aggSlot = AggValueSlot::ignored(),
3217                          bool ignoreResult = false);
3218   LValue EmitCoyieldLValue(const CoyieldExpr *E);
3219   RValue EmitCoroutineIntrinsic(const CallExpr *E, unsigned int IID);
3220 
3221   void EnterCXXTryStmt(const CXXTryStmt &S, bool IsFnTryBlock = false);
3222   void ExitCXXTryStmt(const CXXTryStmt &S, bool IsFnTryBlock = false);
3223 
3224   void EmitCXXTryStmt(const CXXTryStmt &S);
3225   void EmitSEHTryStmt(const SEHTryStmt &S);
3226   void EmitSEHLeaveStmt(const SEHLeaveStmt &S);
3227   void EnterSEHTryStmt(const SEHTryStmt &S);
3228   void ExitSEHTryStmt(const SEHTryStmt &S);
3229   void VolatilizeTryBlocks(llvm::BasicBlock *BB,
3230                            llvm::SmallPtrSet<llvm::BasicBlock *, 10> &V);
3231 
3232   void pushSEHCleanup(CleanupKind kind,
3233                       llvm::Function *FinallyFunc);
3234   void startOutlinedSEHHelper(CodeGenFunction &ParentCGF, bool IsFilter,
3235                               const Stmt *OutlinedStmt);
3236 
3237   llvm::Function *GenerateSEHFilterFunction(CodeGenFunction &ParentCGF,
3238                                             const SEHExceptStmt &Except);
3239 
3240   llvm::Function *GenerateSEHFinallyFunction(CodeGenFunction &ParentCGF,
3241                                              const SEHFinallyStmt &Finally);
3242 
3243   void EmitSEHExceptionCodeSave(CodeGenFunction &ParentCGF,
3244                                 llvm::Value *ParentFP,
3245                                 llvm::Value *EntryEBP);
3246   llvm::Value *EmitSEHExceptionCode();
3247   llvm::Value *EmitSEHExceptionInfo();
3248   llvm::Value *EmitSEHAbnormalTermination();
3249 
3250   /// Emit simple code for OpenMP directives in Simd-only mode.
3251   void EmitSimpleOMPExecutableDirective(const OMPExecutableDirective &D);
3252 
3253   /// Scan the outlined statement for captures from the parent function. For
3254   /// each capture, mark the capture as escaped and emit a call to
3255   /// llvm.localrecover. Insert the localrecover result into the LocalDeclMap.
3256   void EmitCapturedLocals(CodeGenFunction &ParentCGF, const Stmt *OutlinedStmt,
3257                           bool IsFilter);
3258 
3259   /// Recovers the address of a local in a parent function. ParentVar is the
3260   /// address of the variable used in the immediate parent function. It can
3261   /// either be an alloca or a call to llvm.localrecover if there are nested
3262   /// outlined functions. ParentFP is the frame pointer of the outermost parent
3263   /// frame.
3264   Address recoverAddrOfEscapedLocal(CodeGenFunction &ParentCGF,
3265                                     Address ParentVar,
3266                                     llvm::Value *ParentFP);
3267 
3268   void EmitCXXForRangeStmt(const CXXForRangeStmt &S,
3269                            ArrayRef<const Attr *> Attrs = None);
3270 
3271   /// Controls insertion of cancellation exit blocks in worksharing constructs.
3272   class OMPCancelStackRAII {
3273     CodeGenFunction &CGF;
3274 
3275   public:
3276     OMPCancelStackRAII(CodeGenFunction &CGF, OpenMPDirectiveKind Kind,
3277                        bool HasCancel)
3278         : CGF(CGF) {
3279       CGF.OMPCancelStack.enter(CGF, Kind, HasCancel);
3280     }
3281     ~OMPCancelStackRAII() { CGF.OMPCancelStack.exit(CGF); }
3282   };
3283 
3284   /// Returns calculated size of the specified type.
3285   llvm::Value *getTypeSize(QualType Ty);
3286   LValue InitCapturedStruct(const CapturedStmt &S);
3287   llvm::Function *EmitCapturedStmt(const CapturedStmt &S, CapturedRegionKind K);
3288   llvm::Function *GenerateCapturedStmtFunction(const CapturedStmt &S);
3289   Address GenerateCapturedStmtArgument(const CapturedStmt &S);
3290   llvm::Function *GenerateOpenMPCapturedStmtFunction(const CapturedStmt &S,
3291                                                      SourceLocation Loc);
3292   void GenerateOpenMPCapturedVars(const CapturedStmt &S,
3293                                   SmallVectorImpl<llvm::Value *> &CapturedVars);
3294   void emitOMPSimpleStore(LValue LVal, RValue RVal, QualType RValTy,
3295                           SourceLocation Loc);
3296   /// Perform element by element copying of arrays with type \a
3297   /// OriginalType from \a SrcAddr to \a DestAddr using copying procedure
3298   /// generated by \a CopyGen.
3299   ///
3300   /// \param DestAddr Address of the destination array.
3301   /// \param SrcAddr Address of the source array.
3302   /// \param OriginalType Type of destination and source arrays.
3303   /// \param CopyGen Copying procedure that copies value of single array element
3304   /// to another single array element.
3305   void EmitOMPAggregateAssign(
3306       Address DestAddr, Address SrcAddr, QualType OriginalType,
3307       const llvm::function_ref<void(Address, Address)> CopyGen);
3308   /// Emit proper copying of data from one variable to another.
3309   ///
3310   /// \param OriginalType Original type of the copied variables.
3311   /// \param DestAddr Destination address.
3312   /// \param SrcAddr Source address.
3313   /// \param DestVD Destination variable used in \a CopyExpr (for arrays, has
3314   /// type of the base array element).
3315   /// \param SrcVD Source variable used in \a CopyExpr (for arrays, has type of
3316   /// the base array element).
3317   /// \param Copy Actual copygin expression for copying data from \a SrcVD to \a
3318   /// DestVD.
3319   void EmitOMPCopy(QualType OriginalType,
3320                    Address DestAddr, Address SrcAddr,
3321                    const VarDecl *DestVD, const VarDecl *SrcVD,
3322                    const Expr *Copy);
3323   /// Emit atomic update code for constructs: \a X = \a X \a BO \a E or
3324   /// \a X = \a E \a BO \a E.
3325   ///
3326   /// \param X Value to be updated.
3327   /// \param E Update value.
3328   /// \param BO Binary operation for update operation.
3329   /// \param IsXLHSInRHSPart true if \a X is LHS in RHS part of the update
3330   /// expression, false otherwise.
3331   /// \param AO Atomic ordering of the generated atomic instructions.
3332   /// \param CommonGen Code generator for complex expressions that cannot be
3333   /// expressed through atomicrmw instruction.
3334   /// \returns <true, OldAtomicValue> if simple 'atomicrmw' instruction was
3335   /// generated, <false, RValue::get(nullptr)> otherwise.
3336   std::pair<bool, RValue> EmitOMPAtomicSimpleUpdateExpr(
3337       LValue X, RValue E, BinaryOperatorKind BO, bool IsXLHSInRHSPart,
3338       llvm::AtomicOrdering AO, SourceLocation Loc,
3339       const llvm::function_ref<RValue(RValue)> CommonGen);
3340   bool EmitOMPFirstprivateClause(const OMPExecutableDirective &D,
3341                                  OMPPrivateScope &PrivateScope);
3342   void EmitOMPPrivateClause(const OMPExecutableDirective &D,
3343                             OMPPrivateScope &PrivateScope);
3344   void EmitOMPUseDevicePtrClause(
3345       const OMPUseDevicePtrClause &C, OMPPrivateScope &PrivateScope,
3346       const llvm::DenseMap<const ValueDecl *, Address> &CaptureDeviceAddrMap);
3347   void EmitOMPUseDeviceAddrClause(
3348       const OMPUseDeviceAddrClause &C, OMPPrivateScope &PrivateScope,
3349       const llvm::DenseMap<const ValueDecl *, Address> &CaptureDeviceAddrMap);
3350   /// Emit code for copyin clause in \a D directive. The next code is
3351   /// generated at the start of outlined functions for directives:
3352   /// \code
3353   /// threadprivate_var1 = master_threadprivate_var1;
3354   /// operator=(threadprivate_var2, master_threadprivate_var2);
3355   /// ...
3356   /// __kmpc_barrier(&loc, global_tid);
3357   /// \endcode
3358   ///
3359   /// \param D OpenMP directive possibly with 'copyin' clause(s).
3360   /// \returns true if at least one copyin variable is found, false otherwise.
3361   bool EmitOMPCopyinClause(const OMPExecutableDirective &D);
3362   /// Emit initial code for lastprivate variables. If some variable is
3363   /// not also firstprivate, then the default initialization is used. Otherwise
3364   /// initialization of this variable is performed by EmitOMPFirstprivateClause
3365   /// method.
3366   ///
3367   /// \param D Directive that may have 'lastprivate' directives.
3368   /// \param PrivateScope Private scope for capturing lastprivate variables for
3369   /// proper codegen in internal captured statement.
3370   ///
3371   /// \returns true if there is at least one lastprivate variable, false
3372   /// otherwise.
3373   bool EmitOMPLastprivateClauseInit(const OMPExecutableDirective &D,
3374                                     OMPPrivateScope &PrivateScope);
3375   /// Emit final copying of lastprivate values to original variables at
3376   /// the end of the worksharing or simd directive.
3377   ///
3378   /// \param D Directive that has at least one 'lastprivate' directives.
3379   /// \param IsLastIterCond Boolean condition that must be set to 'i1 true' if
3380   /// it is the last iteration of the loop code in associated directive, or to
3381   /// 'i1 false' otherwise. If this item is nullptr, no final check is required.
3382   void EmitOMPLastprivateClauseFinal(const OMPExecutableDirective &D,
3383                                      bool NoFinals,
3384                                      llvm::Value *IsLastIterCond = nullptr);
3385   /// Emit initial code for linear clauses.
3386   void EmitOMPLinearClause(const OMPLoopDirective &D,
3387                            CodeGenFunction::OMPPrivateScope &PrivateScope);
3388   /// Emit final code for linear clauses.
3389   /// \param CondGen Optional conditional code for final part of codegen for
3390   /// linear clause.
3391   void EmitOMPLinearClauseFinal(
3392       const OMPLoopDirective &D,
3393       const llvm::function_ref<llvm::Value *(CodeGenFunction &)> CondGen);
3394   /// Emit initial code for reduction variables. Creates reduction copies
3395   /// and initializes them with the values according to OpenMP standard.
3396   ///
3397   /// \param D Directive (possibly) with the 'reduction' clause.
3398   /// \param PrivateScope Private scope for capturing reduction variables for
3399   /// proper codegen in internal captured statement.
3400   ///
3401   void EmitOMPReductionClauseInit(const OMPExecutableDirective &D,
3402                                   OMPPrivateScope &PrivateScope,
3403                                   bool ForInscan = false);
3404   /// Emit final update of reduction values to original variables at
3405   /// the end of the directive.
3406   ///
3407   /// \param D Directive that has at least one 'reduction' directives.
3408   /// \param ReductionKind The kind of reduction to perform.
3409   void EmitOMPReductionClauseFinal(const OMPExecutableDirective &D,
3410                                    const OpenMPDirectiveKind ReductionKind);
3411   /// Emit initial code for linear variables. Creates private copies
3412   /// and initializes them with the values according to OpenMP standard.
3413   ///
3414   /// \param D Directive (possibly) with the 'linear' clause.
3415   /// \return true if at least one linear variable is found that should be
3416   /// initialized with the value of the original variable, false otherwise.
3417   bool EmitOMPLinearClauseInit(const OMPLoopDirective &D);
3418 
3419   typedef const llvm::function_ref<void(CodeGenFunction & /*CGF*/,
3420                                         llvm::Function * /*OutlinedFn*/,
3421                                         const OMPTaskDataTy & /*Data*/)>
3422       TaskGenTy;
3423   void EmitOMPTaskBasedDirective(const OMPExecutableDirective &S,
3424                                  const OpenMPDirectiveKind CapturedRegion,
3425                                  const RegionCodeGenTy &BodyGen,
3426                                  const TaskGenTy &TaskGen, OMPTaskDataTy &Data);
3427   struct OMPTargetDataInfo {
3428     Address BasePointersArray = Address::invalid();
3429     Address PointersArray = Address::invalid();
3430     Address SizesArray = Address::invalid();
3431     Address MappersArray = Address::invalid();
3432     unsigned NumberOfTargetItems = 0;
3433     explicit OMPTargetDataInfo() = default;
3434     OMPTargetDataInfo(Address BasePointersArray, Address PointersArray,
3435                       Address SizesArray, Address MappersArray,
3436                       unsigned NumberOfTargetItems)
3437         : BasePointersArray(BasePointersArray), PointersArray(PointersArray),
3438           SizesArray(SizesArray), MappersArray(MappersArray),
3439           NumberOfTargetItems(NumberOfTargetItems) {}
3440   };
3441   void EmitOMPTargetTaskBasedDirective(const OMPExecutableDirective &S,
3442                                        const RegionCodeGenTy &BodyGen,
3443                                        OMPTargetDataInfo &InputInfo);
3444 
3445   void EmitOMPParallelDirective(const OMPParallelDirective &S);
3446   void EmitOMPSimdDirective(const OMPSimdDirective &S);
3447   void EmitOMPTileDirective(const OMPTileDirective &S);
3448   void EmitOMPUnrollDirective(const OMPUnrollDirective &S);
3449   void EmitOMPForDirective(const OMPForDirective &S);
3450   void EmitOMPForSimdDirective(const OMPForSimdDirective &S);
3451   void EmitOMPSectionsDirective(const OMPSectionsDirective &S);
3452   void EmitOMPSectionDirective(const OMPSectionDirective &S);
3453   void EmitOMPSingleDirective(const OMPSingleDirective &S);
3454   void EmitOMPMasterDirective(const OMPMasterDirective &S);
3455   void EmitOMPMaskedDirective(const OMPMaskedDirective &S);
3456   void EmitOMPCriticalDirective(const OMPCriticalDirective &S);
3457   void EmitOMPParallelForDirective(const OMPParallelForDirective &S);
3458   void EmitOMPParallelForSimdDirective(const OMPParallelForSimdDirective &S);
3459   void EmitOMPParallelSectionsDirective(const OMPParallelSectionsDirective &S);
3460   void EmitOMPParallelMasterDirective(const OMPParallelMasterDirective &S);
3461   void EmitOMPTaskDirective(const OMPTaskDirective &S);
3462   void EmitOMPTaskyieldDirective(const OMPTaskyieldDirective &S);
3463   void EmitOMPBarrierDirective(const OMPBarrierDirective &S);
3464   void EmitOMPTaskwaitDirective(const OMPTaskwaitDirective &S);
3465   void EmitOMPTaskgroupDirective(const OMPTaskgroupDirective &S);
3466   void EmitOMPFlushDirective(const OMPFlushDirective &S);
3467   void EmitOMPDepobjDirective(const OMPDepobjDirective &S);
3468   void EmitOMPScanDirective(const OMPScanDirective &S);
3469   void EmitOMPOrderedDirective(const OMPOrderedDirective &S);
3470   void EmitOMPAtomicDirective(const OMPAtomicDirective &S);
3471   void EmitOMPTargetDirective(const OMPTargetDirective &S);
3472   void EmitOMPTargetDataDirective(const OMPTargetDataDirective &S);
3473   void EmitOMPTargetEnterDataDirective(const OMPTargetEnterDataDirective &S);
3474   void EmitOMPTargetExitDataDirective(const OMPTargetExitDataDirective &S);
3475   void EmitOMPTargetUpdateDirective(const OMPTargetUpdateDirective &S);
3476   void EmitOMPTargetParallelDirective(const OMPTargetParallelDirective &S);
3477   void
3478   EmitOMPTargetParallelForDirective(const OMPTargetParallelForDirective &S);
3479   void EmitOMPTeamsDirective(const OMPTeamsDirective &S);
3480   void
3481   EmitOMPCancellationPointDirective(const OMPCancellationPointDirective &S);
3482   void EmitOMPCancelDirective(const OMPCancelDirective &S);
3483   void EmitOMPTaskLoopBasedDirective(const OMPLoopDirective &S);
3484   void EmitOMPTaskLoopDirective(const OMPTaskLoopDirective &S);
3485   void EmitOMPTaskLoopSimdDirective(const OMPTaskLoopSimdDirective &S);
3486   void EmitOMPMasterTaskLoopDirective(const OMPMasterTaskLoopDirective &S);
3487   void
3488   EmitOMPMasterTaskLoopSimdDirective(const OMPMasterTaskLoopSimdDirective &S);
3489   void EmitOMPParallelMasterTaskLoopDirective(
3490       const OMPParallelMasterTaskLoopDirective &S);
3491   void EmitOMPParallelMasterTaskLoopSimdDirective(
3492       const OMPParallelMasterTaskLoopSimdDirective &S);
3493   void EmitOMPDistributeDirective(const OMPDistributeDirective &S);
3494   void EmitOMPDistributeParallelForDirective(
3495       const OMPDistributeParallelForDirective &S);
3496   void EmitOMPDistributeParallelForSimdDirective(
3497       const OMPDistributeParallelForSimdDirective &S);
3498   void EmitOMPDistributeSimdDirective(const OMPDistributeSimdDirective &S);
3499   void EmitOMPTargetParallelForSimdDirective(
3500       const OMPTargetParallelForSimdDirective &S);
3501   void EmitOMPTargetSimdDirective(const OMPTargetSimdDirective &S);
3502   void EmitOMPTeamsDistributeDirective(const OMPTeamsDistributeDirective &S);
3503   void
3504   EmitOMPTeamsDistributeSimdDirective(const OMPTeamsDistributeSimdDirective &S);
3505   void EmitOMPTeamsDistributeParallelForSimdDirective(
3506       const OMPTeamsDistributeParallelForSimdDirective &S);
3507   void EmitOMPTeamsDistributeParallelForDirective(
3508       const OMPTeamsDistributeParallelForDirective &S);
3509   void EmitOMPTargetTeamsDirective(const OMPTargetTeamsDirective &S);
3510   void EmitOMPTargetTeamsDistributeDirective(
3511       const OMPTargetTeamsDistributeDirective &S);
3512   void EmitOMPTargetTeamsDistributeParallelForDirective(
3513       const OMPTargetTeamsDistributeParallelForDirective &S);
3514   void EmitOMPTargetTeamsDistributeParallelForSimdDirective(
3515       const OMPTargetTeamsDistributeParallelForSimdDirective &S);
3516   void EmitOMPTargetTeamsDistributeSimdDirective(
3517       const OMPTargetTeamsDistributeSimdDirective &S);
3518 
3519   /// Emit device code for the target directive.
3520   static void EmitOMPTargetDeviceFunction(CodeGenModule &CGM,
3521                                           StringRef ParentName,
3522                                           const OMPTargetDirective &S);
3523   static void
3524   EmitOMPTargetParallelDeviceFunction(CodeGenModule &CGM, StringRef ParentName,
3525                                       const OMPTargetParallelDirective &S);
3526   /// Emit device code for the target parallel for directive.
3527   static void EmitOMPTargetParallelForDeviceFunction(
3528       CodeGenModule &CGM, StringRef ParentName,
3529       const OMPTargetParallelForDirective &S);
3530   /// Emit device code for the target parallel for simd directive.
3531   static void EmitOMPTargetParallelForSimdDeviceFunction(
3532       CodeGenModule &CGM, StringRef ParentName,
3533       const OMPTargetParallelForSimdDirective &S);
3534   /// Emit device code for the target teams directive.
3535   static void
3536   EmitOMPTargetTeamsDeviceFunction(CodeGenModule &CGM, StringRef ParentName,
3537                                    const OMPTargetTeamsDirective &S);
3538   /// Emit device code for the target teams distribute directive.
3539   static void EmitOMPTargetTeamsDistributeDeviceFunction(
3540       CodeGenModule &CGM, StringRef ParentName,
3541       const OMPTargetTeamsDistributeDirective &S);
3542   /// Emit device code for the target teams distribute simd directive.
3543   static void EmitOMPTargetTeamsDistributeSimdDeviceFunction(
3544       CodeGenModule &CGM, StringRef ParentName,
3545       const OMPTargetTeamsDistributeSimdDirective &S);
3546   /// Emit device code for the target simd directive.
3547   static void EmitOMPTargetSimdDeviceFunction(CodeGenModule &CGM,
3548                                               StringRef ParentName,
3549                                               const OMPTargetSimdDirective &S);
3550   /// Emit device code for the target teams distribute parallel for simd
3551   /// directive.
3552   static void EmitOMPTargetTeamsDistributeParallelForSimdDeviceFunction(
3553       CodeGenModule &CGM, StringRef ParentName,
3554       const OMPTargetTeamsDistributeParallelForSimdDirective &S);
3555 
3556   static void EmitOMPTargetTeamsDistributeParallelForDeviceFunction(
3557       CodeGenModule &CGM, StringRef ParentName,
3558       const OMPTargetTeamsDistributeParallelForDirective &S);
3559 
3560   /// Emit the Stmt \p S and return its topmost canonical loop, if any.
3561   /// TODO: The \p Depth paramter is not yet implemented and must be 1. In the
3562   /// future it is meant to be the number of loops expected in the loop nests
3563   /// (usually specified by the "collapse" clause) that are collapsed to a
3564   /// single loop by this function.
3565   llvm::CanonicalLoopInfo *EmitOMPCollapsedCanonicalLoopNest(const Stmt *S,
3566                                                              int Depth);
3567 
3568   /// Emit an OMPCanonicalLoop using the OpenMPIRBuilder.
3569   void EmitOMPCanonicalLoop(const OMPCanonicalLoop *S);
3570 
3571   /// Emit inner loop of the worksharing/simd construct.
3572   ///
3573   /// \param S Directive, for which the inner loop must be emitted.
3574   /// \param RequiresCleanup true, if directive has some associated private
3575   /// variables.
3576   /// \param LoopCond Bollean condition for loop continuation.
3577   /// \param IncExpr Increment expression for loop control variable.
3578   /// \param BodyGen Generator for the inner body of the inner loop.
3579   /// \param PostIncGen Genrator for post-increment code (required for ordered
3580   /// loop directvies).
3581   void EmitOMPInnerLoop(
3582       const OMPExecutableDirective &S, bool RequiresCleanup,
3583       const Expr *LoopCond, const Expr *IncExpr,
3584       const llvm::function_ref<void(CodeGenFunction &)> BodyGen,
3585       const llvm::function_ref<void(CodeGenFunction &)> PostIncGen);
3586 
3587   JumpDest getOMPCancelDestination(OpenMPDirectiveKind Kind);
3588   /// Emit initial code for loop counters of loop-based directives.
3589   void EmitOMPPrivateLoopCounters(const OMPLoopDirective &S,
3590                                   OMPPrivateScope &LoopScope);
3591 
3592   /// Helper for the OpenMP loop directives.
3593   void EmitOMPLoopBody(const OMPLoopDirective &D, JumpDest LoopExit);
3594 
3595   /// Emit code for the worksharing loop-based directive.
3596   /// \return true, if this construct has any lastprivate clause, false -
3597   /// otherwise.
3598   bool EmitOMPWorksharingLoop(const OMPLoopDirective &S, Expr *EUB,
3599                               const CodeGenLoopBoundsTy &CodeGenLoopBounds,
3600                               const CodeGenDispatchBoundsTy &CGDispatchBounds);
3601 
3602   /// Emit code for the distribute loop-based directive.
3603   void EmitOMPDistributeLoop(const OMPLoopDirective &S,
3604                              const CodeGenLoopTy &CodeGenLoop, Expr *IncExpr);
3605 
3606   /// Helpers for the OpenMP loop directives.
3607   void EmitOMPSimdInit(const OMPLoopDirective &D);
3608   void EmitOMPSimdFinal(
3609       const OMPLoopDirective &D,
3610       const llvm::function_ref<llvm::Value *(CodeGenFunction &)> CondGen);
3611 
3612   /// Emits the lvalue for the expression with possibly captured variable.
3613   LValue EmitOMPSharedLValue(const Expr *E);
3614 
3615 private:
3616   /// Helpers for blocks.
3617   llvm::Value *EmitBlockLiteral(const CGBlockInfo &Info);
3618 
3619   /// struct with the values to be passed to the OpenMP loop-related functions
3620   struct OMPLoopArguments {
3621     /// loop lower bound
3622     Address LB = Address::invalid();
3623     /// loop upper bound
3624     Address UB = Address::invalid();
3625     /// loop stride
3626     Address ST = Address::invalid();
3627     /// isLastIteration argument for runtime functions
3628     Address IL = Address::invalid();
3629     /// Chunk value generated by sema
3630     llvm::Value *Chunk = nullptr;
3631     /// EnsureUpperBound
3632     Expr *EUB = nullptr;
3633     /// IncrementExpression
3634     Expr *IncExpr = nullptr;
3635     /// Loop initialization
3636     Expr *Init = nullptr;
3637     /// Loop exit condition
3638     Expr *Cond = nullptr;
3639     /// Update of LB after a whole chunk has been executed
3640     Expr *NextLB = nullptr;
3641     /// Update of UB after a whole chunk has been executed
3642     Expr *NextUB = nullptr;
3643     OMPLoopArguments() = default;
3644     OMPLoopArguments(Address LB, Address UB, Address ST, Address IL,
3645                      llvm::Value *Chunk = nullptr, Expr *EUB = nullptr,
3646                      Expr *IncExpr = nullptr, Expr *Init = nullptr,
3647                      Expr *Cond = nullptr, Expr *NextLB = nullptr,
3648                      Expr *NextUB = nullptr)
3649         : LB(LB), UB(UB), ST(ST), IL(IL), Chunk(Chunk), EUB(EUB),
3650           IncExpr(IncExpr), Init(Init), Cond(Cond), NextLB(NextLB),
3651           NextUB(NextUB) {}
3652   };
3653   void EmitOMPOuterLoop(bool DynamicOrOrdered, bool IsMonotonic,
3654                         const OMPLoopDirective &S, OMPPrivateScope &LoopScope,
3655                         const OMPLoopArguments &LoopArgs,
3656                         const CodeGenLoopTy &CodeGenLoop,
3657                         const CodeGenOrderedTy &CodeGenOrdered);
3658   void EmitOMPForOuterLoop(const OpenMPScheduleTy &ScheduleKind,
3659                            bool IsMonotonic, const OMPLoopDirective &S,
3660                            OMPPrivateScope &LoopScope, bool Ordered,
3661                            const OMPLoopArguments &LoopArgs,
3662                            const CodeGenDispatchBoundsTy &CGDispatchBounds);
3663   void EmitOMPDistributeOuterLoop(OpenMPDistScheduleClauseKind ScheduleKind,
3664                                   const OMPLoopDirective &S,
3665                                   OMPPrivateScope &LoopScope,
3666                                   const OMPLoopArguments &LoopArgs,
3667                                   const CodeGenLoopTy &CodeGenLoopContent);
3668   /// Emit code for sections directive.
3669   void EmitSections(const OMPExecutableDirective &S);
3670 
3671 public:
3672 
3673   //===--------------------------------------------------------------------===//
3674   //                         LValue Expression Emission
3675   //===--------------------------------------------------------------------===//
3676 
3677   /// Create a check that a scalar RValue is non-null.
3678   llvm::Value *EmitNonNullRValueCheck(RValue RV, QualType T);
3679 
3680   /// GetUndefRValue - Get an appropriate 'undef' rvalue for the given type.
3681   RValue GetUndefRValue(QualType Ty);
3682 
3683   /// EmitUnsupportedRValue - Emit a dummy r-value using the type of E
3684   /// and issue an ErrorUnsupported style diagnostic (using the
3685   /// provided Name).
3686   RValue EmitUnsupportedRValue(const Expr *E,
3687                                const char *Name);
3688 
3689   /// EmitUnsupportedLValue - Emit a dummy l-value using the type of E and issue
3690   /// an ErrorUnsupported style diagnostic (using the provided Name).
3691   LValue EmitUnsupportedLValue(const Expr *E,
3692                                const char *Name);
3693 
3694   /// EmitLValue - Emit code to compute a designator that specifies the location
3695   /// of the expression.
3696   ///
3697   /// This can return one of two things: a simple address or a bitfield
3698   /// reference.  In either case, the LLVM Value* in the LValue structure is
3699   /// guaranteed to be an LLVM pointer type.
3700   ///
3701   /// If this returns a bitfield reference, nothing about the pointee type of
3702   /// the LLVM value is known: For example, it may not be a pointer to an
3703   /// integer.
3704   ///
3705   /// If this returns a normal address, and if the lvalue's C type is fixed
3706   /// size, this method guarantees that the returned pointer type will point to
3707   /// an LLVM type of the same size of the lvalue's type.  If the lvalue has a
3708   /// variable length type, this is not possible.
3709   ///
3710   LValue EmitLValue(const Expr *E);
3711 
3712   /// Same as EmitLValue but additionally we generate checking code to
3713   /// guard against undefined behavior.  This is only suitable when we know
3714   /// that the address will be used to access the object.
3715   LValue EmitCheckedLValue(const Expr *E, TypeCheckKind TCK);
3716 
3717   RValue convertTempToRValue(Address addr, QualType type,
3718                              SourceLocation Loc);
3719 
3720   void EmitAtomicInit(Expr *E, LValue lvalue);
3721 
3722   bool LValueIsSuitableForInlineAtomic(LValue Src);
3723 
3724   RValue EmitAtomicLoad(LValue LV, SourceLocation SL,
3725                         AggValueSlot Slot = AggValueSlot::ignored());
3726 
3727   RValue EmitAtomicLoad(LValue lvalue, SourceLocation loc,
3728                         llvm::AtomicOrdering AO, bool IsVolatile = false,
3729                         AggValueSlot slot = AggValueSlot::ignored());
3730 
3731   void EmitAtomicStore(RValue rvalue, LValue lvalue, bool isInit);
3732 
3733   void EmitAtomicStore(RValue rvalue, LValue lvalue, llvm::AtomicOrdering AO,
3734                        bool IsVolatile, bool isInit);
3735 
3736   std::pair<RValue, llvm::Value *> EmitAtomicCompareExchange(
3737       LValue Obj, RValue Expected, RValue Desired, SourceLocation Loc,
3738       llvm::AtomicOrdering Success =
3739           llvm::AtomicOrdering::SequentiallyConsistent,
3740       llvm::AtomicOrdering Failure =
3741           llvm::AtomicOrdering::SequentiallyConsistent,
3742       bool IsWeak = false, AggValueSlot Slot = AggValueSlot::ignored());
3743 
3744   void EmitAtomicUpdate(LValue LVal, llvm::AtomicOrdering AO,
3745                         const llvm::function_ref<RValue(RValue)> &UpdateOp,
3746                         bool IsVolatile);
3747 
3748   /// EmitToMemory - Change a scalar value from its value
3749   /// representation to its in-memory representation.
3750   llvm::Value *EmitToMemory(llvm::Value *Value, QualType Ty);
3751 
3752   /// EmitFromMemory - Change a scalar value from its memory
3753   /// representation to its value representation.
3754   llvm::Value *EmitFromMemory(llvm::Value *Value, QualType Ty);
3755 
3756   /// Check if the scalar \p Value is within the valid range for the given
3757   /// type \p Ty.
3758   ///
3759   /// Returns true if a check is needed (even if the range is unknown).
3760   bool EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
3761                             SourceLocation Loc);
3762 
3763   /// EmitLoadOfScalar - Load a scalar value from an address, taking
3764   /// care to appropriately convert from the memory representation to
3765   /// the LLVM value representation.
3766   llvm::Value *EmitLoadOfScalar(Address Addr, bool Volatile, QualType Ty,
3767                                 SourceLocation Loc,
3768                                 AlignmentSource Source = AlignmentSource::Type,
3769                                 bool isNontemporal = false) {
3770     return EmitLoadOfScalar(Addr, Volatile, Ty, Loc, LValueBaseInfo(Source),
3771                             CGM.getTBAAAccessInfo(Ty), isNontemporal);
3772   }
3773 
3774   llvm::Value *EmitLoadOfScalar(Address Addr, bool Volatile, QualType Ty,
3775                                 SourceLocation Loc, LValueBaseInfo BaseInfo,
3776                                 TBAAAccessInfo TBAAInfo,
3777                                 bool isNontemporal = false);
3778 
3779   /// EmitLoadOfScalar - Load a scalar value from an address, taking
3780   /// care to appropriately convert from the memory representation to
3781   /// the LLVM value representation.  The l-value must be a simple
3782   /// l-value.
3783   llvm::Value *EmitLoadOfScalar(LValue lvalue, SourceLocation Loc);
3784 
3785   /// EmitStoreOfScalar - Store a scalar value to an address, taking
3786   /// care to appropriately convert from the memory representation to
3787   /// the LLVM value representation.
3788   void EmitStoreOfScalar(llvm::Value *Value, Address Addr,
3789                          bool Volatile, QualType Ty,
3790                          AlignmentSource Source = AlignmentSource::Type,
3791                          bool isInit = false, bool isNontemporal = false) {
3792     EmitStoreOfScalar(Value, Addr, Volatile, Ty, LValueBaseInfo(Source),
3793                       CGM.getTBAAAccessInfo(Ty), isInit, isNontemporal);
3794   }
3795 
3796   void EmitStoreOfScalar(llvm::Value *Value, Address Addr,
3797                          bool Volatile, QualType Ty,
3798                          LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo,
3799                          bool isInit = false, bool isNontemporal = false);
3800 
3801   /// EmitStoreOfScalar - Store a scalar value to an address, taking
3802   /// care to appropriately convert from the memory representation to
3803   /// the LLVM value representation.  The l-value must be a simple
3804   /// l-value.  The isInit flag indicates whether this is an initialization.
3805   /// If so, atomic qualifiers are ignored and the store is always non-atomic.
3806   void EmitStoreOfScalar(llvm::Value *value, LValue lvalue, bool isInit=false);
3807 
3808   /// EmitLoadOfLValue - Given an expression that represents a value lvalue,
3809   /// this method emits the address of the lvalue, then loads the result as an
3810   /// rvalue, returning the rvalue.
3811   RValue EmitLoadOfLValue(LValue V, SourceLocation Loc);
3812   RValue EmitLoadOfExtVectorElementLValue(LValue V);
3813   RValue EmitLoadOfBitfieldLValue(LValue LV, SourceLocation Loc);
3814   RValue EmitLoadOfGlobalRegLValue(LValue LV);
3815 
3816   /// EmitStoreThroughLValue - Store the specified rvalue into the specified
3817   /// lvalue, where both are guaranteed to the have the same type, and that type
3818   /// is 'Ty'.
3819   void EmitStoreThroughLValue(RValue Src, LValue Dst, bool isInit = false);
3820   void EmitStoreThroughExtVectorComponentLValue(RValue Src, LValue Dst);
3821   void EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst);
3822 
3823   /// EmitStoreThroughBitfieldLValue - Store Src into Dst with same constraints
3824   /// as EmitStoreThroughLValue.
3825   ///
3826   /// \param Result [out] - If non-null, this will be set to a Value* for the
3827   /// bit-field contents after the store, appropriate for use as the result of
3828   /// an assignment to the bit-field.
3829   void EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
3830                                       llvm::Value **Result=nullptr);
3831 
3832   /// Emit an l-value for an assignment (simple or compound) of complex type.
3833   LValue EmitComplexAssignmentLValue(const BinaryOperator *E);
3834   LValue EmitComplexCompoundAssignmentLValue(const CompoundAssignOperator *E);
3835   LValue EmitScalarCompoundAssignWithComplex(const CompoundAssignOperator *E,
3836                                              llvm::Value *&Result);
3837 
3838   // Note: only available for agg return types
3839   LValue EmitBinaryOperatorLValue(const BinaryOperator *E);
3840   LValue EmitCompoundAssignmentLValue(const CompoundAssignOperator *E);
3841   // Note: only available for agg return types
3842   LValue EmitCallExprLValue(const CallExpr *E);
3843   // Note: only available for agg return types
3844   LValue EmitVAArgExprLValue(const VAArgExpr *E);
3845   LValue EmitDeclRefLValue(const DeclRefExpr *E);
3846   LValue EmitStringLiteralLValue(const StringLiteral *E);
3847   LValue EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E);
3848   LValue EmitPredefinedLValue(const PredefinedExpr *E);
3849   LValue EmitUnaryOpLValue(const UnaryOperator *E);
3850   LValue EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3851                                 bool Accessed = false);
3852   LValue EmitMatrixSubscriptExpr(const MatrixSubscriptExpr *E);
3853   LValue EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3854                                  bool IsLowerBound = true);
3855   LValue EmitExtVectorElementExpr(const ExtVectorElementExpr *E);
3856   LValue EmitMemberExpr(const MemberExpr *E);
3857   LValue EmitObjCIsaExpr(const ObjCIsaExpr *E);
3858   LValue EmitCompoundLiteralLValue(const CompoundLiteralExpr *E);
3859   LValue EmitInitListLValue(const InitListExpr *E);
3860   LValue EmitConditionalOperatorLValue(const AbstractConditionalOperator *E);
3861   LValue EmitCastLValue(const CastExpr *E);
3862   LValue EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E);
3863   LValue EmitOpaqueValueLValue(const OpaqueValueExpr *e);
3864 
3865   Address EmitExtVectorElementLValue(LValue V);
3866 
3867   RValue EmitRValueForField(LValue LV, const FieldDecl *FD, SourceLocation Loc);
3868 
3869   Address EmitArrayToPointerDecay(const Expr *Array,
3870                                   LValueBaseInfo *BaseInfo = nullptr,
3871                                   TBAAAccessInfo *TBAAInfo = nullptr);
3872 
3873   class ConstantEmission {
3874     llvm::PointerIntPair<llvm::Constant*, 1, bool> ValueAndIsReference;
3875     ConstantEmission(llvm::Constant *C, bool isReference)
3876       : ValueAndIsReference(C, isReference) {}
3877   public:
3878     ConstantEmission() {}
3879     static ConstantEmission forReference(llvm::Constant *C) {
3880       return ConstantEmission(C, true);
3881     }
3882     static ConstantEmission forValue(llvm::Constant *C) {
3883       return ConstantEmission(C, false);
3884     }
3885 
3886     explicit operator bool() const {
3887       return ValueAndIsReference.getOpaqueValue() != nullptr;
3888     }
3889 
3890     bool isReference() const { return ValueAndIsReference.getInt(); }
3891     LValue getReferenceLValue(CodeGenFunction &CGF, Expr *refExpr) const {
3892       assert(isReference());
3893       return CGF.MakeNaturalAlignAddrLValue(ValueAndIsReference.getPointer(),
3894                                             refExpr->getType());
3895     }
3896 
3897     llvm::Constant *getValue() const {
3898       assert(!isReference());
3899       return ValueAndIsReference.getPointer();
3900     }
3901   };
3902 
3903   ConstantEmission tryEmitAsConstant(DeclRefExpr *refExpr);
3904   ConstantEmission tryEmitAsConstant(const MemberExpr *ME);
3905   llvm::Value *emitScalarConstant(const ConstantEmission &Constant, Expr *E);
3906 
3907   RValue EmitPseudoObjectRValue(const PseudoObjectExpr *e,
3908                                 AggValueSlot slot = AggValueSlot::ignored());
3909   LValue EmitPseudoObjectLValue(const PseudoObjectExpr *e);
3910 
3911   llvm::Value *EmitIvarOffset(const ObjCInterfaceDecl *Interface,
3912                               const ObjCIvarDecl *Ivar);
3913   LValue EmitLValueForField(LValue Base, const FieldDecl* Field);
3914   LValue EmitLValueForLambdaField(const FieldDecl *Field);
3915 
3916   /// EmitLValueForFieldInitialization - Like EmitLValueForField, except that
3917   /// if the Field is a reference, this will return the address of the reference
3918   /// and not the address of the value stored in the reference.
3919   LValue EmitLValueForFieldInitialization(LValue Base,
3920                                           const FieldDecl* Field);
3921 
3922   LValue EmitLValueForIvar(QualType ObjectTy,
3923                            llvm::Value* Base, const ObjCIvarDecl *Ivar,
3924                            unsigned CVRQualifiers);
3925 
3926   LValue EmitCXXConstructLValue(const CXXConstructExpr *E);
3927   LValue EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E);
3928   LValue EmitCXXTypeidLValue(const CXXTypeidExpr *E);
3929   LValue EmitCXXUuidofLValue(const CXXUuidofExpr *E);
3930 
3931   LValue EmitObjCMessageExprLValue(const ObjCMessageExpr *E);
3932   LValue EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E);
3933   LValue EmitStmtExprLValue(const StmtExpr *E);
3934   LValue EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E);
3935   LValue EmitObjCSelectorLValue(const ObjCSelectorExpr *E);
3936   void   EmitDeclRefExprDbgValue(const DeclRefExpr *E, const APValue &Init);
3937 
3938   //===--------------------------------------------------------------------===//
3939   //                         Scalar Expression Emission
3940   //===--------------------------------------------------------------------===//
3941 
3942   /// EmitCall - Generate a call of the given function, expecting the given
3943   /// result type, and using the given argument list which specifies both the
3944   /// LLVM arguments and the types they were derived from.
3945   RValue EmitCall(const CGFunctionInfo &CallInfo, const CGCallee &Callee,
3946                   ReturnValueSlot ReturnValue, const CallArgList &Args,
3947                   llvm::CallBase **callOrInvoke, bool IsMustTail,
3948                   SourceLocation Loc);
3949   RValue EmitCall(const CGFunctionInfo &CallInfo, const CGCallee &Callee,
3950                   ReturnValueSlot ReturnValue, const CallArgList &Args,
3951                   llvm::CallBase **callOrInvoke = nullptr,
3952                   bool IsMustTail = false) {
3953     return EmitCall(CallInfo, Callee, ReturnValue, Args, callOrInvoke,
3954                     IsMustTail, SourceLocation());
3955   }
3956   RValue EmitCall(QualType FnType, const CGCallee &Callee, const CallExpr *E,
3957                   ReturnValueSlot ReturnValue, llvm::Value *Chain = nullptr);
3958   RValue EmitCallExpr(const CallExpr *E,
3959                       ReturnValueSlot ReturnValue = ReturnValueSlot());
3960   RValue EmitSimpleCallExpr(const CallExpr *E, ReturnValueSlot ReturnValue);
3961   CGCallee EmitCallee(const Expr *E);
3962 
3963   void checkTargetFeatures(const CallExpr *E, const FunctionDecl *TargetDecl);
3964   void checkTargetFeatures(SourceLocation Loc, const FunctionDecl *TargetDecl);
3965 
3966   llvm::CallInst *EmitRuntimeCall(llvm::FunctionCallee callee,
3967                                   const Twine &name = "");
3968   llvm::CallInst *EmitRuntimeCall(llvm::FunctionCallee callee,
3969                                   ArrayRef<llvm::Value *> args,
3970                                   const Twine &name = "");
3971   llvm::CallInst *EmitNounwindRuntimeCall(llvm::FunctionCallee callee,
3972                                           const Twine &name = "");
3973   llvm::CallInst *EmitNounwindRuntimeCall(llvm::FunctionCallee callee,
3974                                           ArrayRef<llvm::Value *> args,
3975                                           const Twine &name = "");
3976 
3977   SmallVector<llvm::OperandBundleDef, 1>
3978   getBundlesForFunclet(llvm::Value *Callee);
3979 
3980   llvm::CallBase *EmitCallOrInvoke(llvm::FunctionCallee Callee,
3981                                    ArrayRef<llvm::Value *> Args,
3982                                    const Twine &Name = "");
3983   llvm::CallBase *EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee,
3984                                           ArrayRef<llvm::Value *> args,
3985                                           const Twine &name = "");
3986   llvm::CallBase *EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee,
3987                                           const Twine &name = "");
3988   void EmitNoreturnRuntimeCallOrInvoke(llvm::FunctionCallee callee,
3989                                        ArrayRef<llvm::Value *> args);
3990 
3991   CGCallee BuildAppleKextVirtualCall(const CXXMethodDecl *MD,
3992                                      NestedNameSpecifier *Qual,
3993                                      llvm::Type *Ty);
3994 
3995   CGCallee BuildAppleKextVirtualDestructorCall(const CXXDestructorDecl *DD,
3996                                                CXXDtorType Type,
3997                                                const CXXRecordDecl *RD);
3998 
3999   // Return the copy constructor name with the prefix "__copy_constructor_"
4000   // removed.
4001   static std::string getNonTrivialCopyConstructorStr(QualType QT,
4002                                                      CharUnits Alignment,
4003                                                      bool IsVolatile,
4004                                                      ASTContext &Ctx);
4005 
4006   // Return the destructor name with the prefix "__destructor_" removed.
4007   static std::string getNonTrivialDestructorStr(QualType QT,
4008                                                 CharUnits Alignment,
4009                                                 bool IsVolatile,
4010                                                 ASTContext &Ctx);
4011 
4012   // These functions emit calls to the special functions of non-trivial C
4013   // structs.
4014   void defaultInitNonTrivialCStructVar(LValue Dst);
4015   void callCStructDefaultConstructor(LValue Dst);
4016   void callCStructDestructor(LValue Dst);
4017   void callCStructCopyConstructor(LValue Dst, LValue Src);
4018   void callCStructMoveConstructor(LValue Dst, LValue Src);
4019   void callCStructCopyAssignmentOperator(LValue Dst, LValue Src);
4020   void callCStructMoveAssignmentOperator(LValue Dst, LValue Src);
4021 
4022   RValue
4023   EmitCXXMemberOrOperatorCall(const CXXMethodDecl *Method,
4024                               const CGCallee &Callee,
4025                               ReturnValueSlot ReturnValue, llvm::Value *This,
4026                               llvm::Value *ImplicitParam,
4027                               QualType ImplicitParamTy, const CallExpr *E,
4028                               CallArgList *RtlArgs);
4029   RValue EmitCXXDestructorCall(GlobalDecl Dtor, const CGCallee &Callee,
4030                                llvm::Value *This, QualType ThisTy,
4031                                llvm::Value *ImplicitParam,
4032                                QualType ImplicitParamTy, const CallExpr *E);
4033   RValue EmitCXXMemberCallExpr(const CXXMemberCallExpr *E,
4034                                ReturnValueSlot ReturnValue);
4035   RValue EmitCXXMemberOrOperatorMemberCallExpr(const CallExpr *CE,
4036                                                const CXXMethodDecl *MD,
4037                                                ReturnValueSlot ReturnValue,
4038                                                bool HasQualifier,
4039                                                NestedNameSpecifier *Qualifier,
4040                                                bool IsArrow, const Expr *Base);
4041   // Compute the object pointer.
4042   Address EmitCXXMemberDataPointerAddress(const Expr *E, Address base,
4043                                           llvm::Value *memberPtr,
4044                                           const MemberPointerType *memberPtrType,
4045                                           LValueBaseInfo *BaseInfo = nullptr,
4046                                           TBAAAccessInfo *TBAAInfo = nullptr);
4047   RValue EmitCXXMemberPointerCallExpr(const CXXMemberCallExpr *E,
4048                                       ReturnValueSlot ReturnValue);
4049 
4050   RValue EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
4051                                        const CXXMethodDecl *MD,
4052                                        ReturnValueSlot ReturnValue);
4053   RValue EmitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E);
4054 
4055   RValue EmitCUDAKernelCallExpr(const CUDAKernelCallExpr *E,
4056                                 ReturnValueSlot ReturnValue);
4057 
4058   RValue EmitNVPTXDevicePrintfCallExpr(const CallExpr *E,
4059                                        ReturnValueSlot ReturnValue);
4060   RValue EmitAMDGPUDevicePrintfCallExpr(const CallExpr *E,
4061                                         ReturnValueSlot ReturnValue);
4062 
4063   RValue EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
4064                          const CallExpr *E, ReturnValueSlot ReturnValue);
4065 
4066   RValue emitRotate(const CallExpr *E, bool IsRotateRight);
4067 
4068   /// Emit IR for __builtin_os_log_format.
4069   RValue emitBuiltinOSLogFormat(const CallExpr &E);
4070 
4071   /// Emit IR for __builtin_is_aligned.
4072   RValue EmitBuiltinIsAligned(const CallExpr *E);
4073   /// Emit IR for __builtin_align_up/__builtin_align_down.
4074   RValue EmitBuiltinAlignTo(const CallExpr *E, bool AlignUp);
4075 
4076   llvm::Function *generateBuiltinOSLogHelperFunction(
4077       const analyze_os_log::OSLogBufferLayout &Layout,
4078       CharUnits BufferAlignment);
4079 
4080   RValue EmitBlockCallExpr(const CallExpr *E, ReturnValueSlot ReturnValue);
4081 
4082   /// EmitTargetBuiltinExpr - Emit the given builtin call. Returns 0 if the call
4083   /// is unhandled by the current target.
4084   llvm::Value *EmitTargetBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4085                                      ReturnValueSlot ReturnValue);
4086 
4087   llvm::Value *EmitAArch64CompareBuiltinExpr(llvm::Value *Op, llvm::Type *Ty,
4088                                              const llvm::CmpInst::Predicate Fp,
4089                                              const llvm::CmpInst::Predicate Ip,
4090                                              const llvm::Twine &Name = "");
4091   llvm::Value *EmitARMBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4092                                   ReturnValueSlot ReturnValue,
4093                                   llvm::Triple::ArchType Arch);
4094   llvm::Value *EmitARMMVEBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4095                                      ReturnValueSlot ReturnValue,
4096                                      llvm::Triple::ArchType Arch);
4097   llvm::Value *EmitARMCDEBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4098                                      ReturnValueSlot ReturnValue,
4099                                      llvm::Triple::ArchType Arch);
4100   llvm::Value *EmitCMSEClearRecord(llvm::Value *V, llvm::IntegerType *ITy,
4101                                    QualType RTy);
4102   llvm::Value *EmitCMSEClearRecord(llvm::Value *V, llvm::ArrayType *ATy,
4103                                    QualType RTy);
4104 
4105   llvm::Value *EmitCommonNeonBuiltinExpr(unsigned BuiltinID,
4106                                          unsigned LLVMIntrinsic,
4107                                          unsigned AltLLVMIntrinsic,
4108                                          const char *NameHint,
4109                                          unsigned Modifier,
4110                                          const CallExpr *E,
4111                                          SmallVectorImpl<llvm::Value *> &Ops,
4112                                          Address PtrOp0, Address PtrOp1,
4113                                          llvm::Triple::ArchType Arch);
4114 
4115   llvm::Function *LookupNeonLLVMIntrinsic(unsigned IntrinsicID,
4116                                           unsigned Modifier, llvm::Type *ArgTy,
4117                                           const CallExpr *E);
4118   llvm::Value *EmitNeonCall(llvm::Function *F,
4119                             SmallVectorImpl<llvm::Value*> &O,
4120                             const char *name,
4121                             unsigned shift = 0, bool rightshift = false);
4122   llvm::Value *EmitNeonSplat(llvm::Value *V, llvm::Constant *Idx,
4123                              const llvm::ElementCount &Count);
4124   llvm::Value *EmitNeonSplat(llvm::Value *V, llvm::Constant *Idx);
4125   llvm::Value *EmitNeonShiftVector(llvm::Value *V, llvm::Type *Ty,
4126                                    bool negateForRightShift);
4127   llvm::Value *EmitNeonRShiftImm(llvm::Value *Vec, llvm::Value *Amt,
4128                                  llvm::Type *Ty, bool usgn, const char *name);
4129   llvm::Value *vectorWrapScalar16(llvm::Value *Op);
4130   /// SVEBuiltinMemEltTy - Returns the memory element type for this memory
4131   /// access builtin.  Only required if it can't be inferred from the base
4132   /// pointer operand.
4133   llvm::Type *SVEBuiltinMemEltTy(const SVETypeFlags &TypeFlags);
4134 
4135   SmallVector<llvm::Type *, 2>
4136   getSVEOverloadTypes(const SVETypeFlags &TypeFlags, llvm::Type *ReturnType,
4137                       ArrayRef<llvm::Value *> Ops);
4138   llvm::Type *getEltType(const SVETypeFlags &TypeFlags);
4139   llvm::ScalableVectorType *getSVEType(const SVETypeFlags &TypeFlags);
4140   llvm::ScalableVectorType *getSVEPredType(const SVETypeFlags &TypeFlags);
4141   llvm::Value *EmitSVEAllTruePred(const SVETypeFlags &TypeFlags);
4142   llvm::Value *EmitSVEDupX(llvm::Value *Scalar);
4143   llvm::Value *EmitSVEDupX(llvm::Value *Scalar, llvm::Type *Ty);
4144   llvm::Value *EmitSVEReinterpret(llvm::Value *Val, llvm::Type *Ty);
4145   llvm::Value *EmitSVEPMull(const SVETypeFlags &TypeFlags,
4146                             llvm::SmallVectorImpl<llvm::Value *> &Ops,
4147                             unsigned BuiltinID);
4148   llvm::Value *EmitSVEMovl(const SVETypeFlags &TypeFlags,
4149                            llvm::ArrayRef<llvm::Value *> Ops,
4150                            unsigned BuiltinID);
4151   llvm::Value *EmitSVEPredicateCast(llvm::Value *Pred,
4152                                     llvm::ScalableVectorType *VTy);
4153   llvm::Value *EmitSVEGatherLoad(const SVETypeFlags &TypeFlags,
4154                                  llvm::SmallVectorImpl<llvm::Value *> &Ops,
4155                                  unsigned IntID);
4156   llvm::Value *EmitSVEScatterStore(const SVETypeFlags &TypeFlags,
4157                                    llvm::SmallVectorImpl<llvm::Value *> &Ops,
4158                                    unsigned IntID);
4159   llvm::Value *EmitSVEMaskedLoad(const CallExpr *, llvm::Type *ReturnTy,
4160                                  SmallVectorImpl<llvm::Value *> &Ops,
4161                                  unsigned BuiltinID, bool IsZExtReturn);
4162   llvm::Value *EmitSVEMaskedStore(const CallExpr *,
4163                                   SmallVectorImpl<llvm::Value *> &Ops,
4164                                   unsigned BuiltinID);
4165   llvm::Value *EmitSVEPrefetchLoad(const SVETypeFlags &TypeFlags,
4166                                    SmallVectorImpl<llvm::Value *> &Ops,
4167                                    unsigned BuiltinID);
4168   llvm::Value *EmitSVEGatherPrefetch(const SVETypeFlags &TypeFlags,
4169                                      SmallVectorImpl<llvm::Value *> &Ops,
4170                                      unsigned IntID);
4171   llvm::Value *EmitSVEStructLoad(const SVETypeFlags &TypeFlags,
4172                                  SmallVectorImpl<llvm::Value *> &Ops,
4173                                  unsigned IntID);
4174   llvm::Value *EmitSVEStructStore(const SVETypeFlags &TypeFlags,
4175                                   SmallVectorImpl<llvm::Value *> &Ops,
4176                                   unsigned IntID);
4177   llvm::Value *EmitAArch64SVEBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4178 
4179   llvm::Value *EmitAArch64BuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4180                                       llvm::Triple::ArchType Arch);
4181   llvm::Value *EmitBPFBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4182 
4183   llvm::Value *BuildVector(ArrayRef<llvm::Value*> Ops);
4184   llvm::Value *EmitX86BuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4185   llvm::Value *EmitPPCBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4186   llvm::Value *EmitAMDGPUBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4187   llvm::Value *EmitSystemZBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4188   llvm::Value *EmitNVPTXBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4189   llvm::Value *EmitWebAssemblyBuiltinExpr(unsigned BuiltinID,
4190                                           const CallExpr *E);
4191   llvm::Value *EmitHexagonBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4192   llvm::Value *EmitRISCVBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4193                                     ReturnValueSlot ReturnValue);
4194   bool ProcessOrderScopeAMDGCN(llvm::Value *Order, llvm::Value *Scope,
4195                                llvm::AtomicOrdering &AO,
4196                                llvm::SyncScope::ID &SSID);
4197 
4198   enum class MSVCIntrin;
4199   llvm::Value *EmitMSVCBuiltinExpr(MSVCIntrin BuiltinID, const CallExpr *E);
4200 
4201   llvm::Value *EmitBuiltinAvailable(const VersionTuple &Version);
4202 
4203   llvm::Value *EmitObjCProtocolExpr(const ObjCProtocolExpr *E);
4204   llvm::Value *EmitObjCStringLiteral(const ObjCStringLiteral *E);
4205   llvm::Value *EmitObjCBoxedExpr(const ObjCBoxedExpr *E);
4206   llvm::Value *EmitObjCArrayLiteral(const ObjCArrayLiteral *E);
4207   llvm::Value *EmitObjCDictionaryLiteral(const ObjCDictionaryLiteral *E);
4208   llvm::Value *EmitObjCCollectionLiteral(const Expr *E,
4209                                 const ObjCMethodDecl *MethodWithObjects);
4210   llvm::Value *EmitObjCSelectorExpr(const ObjCSelectorExpr *E);
4211   RValue EmitObjCMessageExpr(const ObjCMessageExpr *E,
4212                              ReturnValueSlot Return = ReturnValueSlot());
4213 
4214   /// Retrieves the default cleanup kind for an ARC cleanup.
4215   /// Except under -fobjc-arc-eh, ARC cleanups are normal-only.
4216   CleanupKind getARCCleanupKind() {
4217     return CGM.getCodeGenOpts().ObjCAutoRefCountExceptions
4218              ? NormalAndEHCleanup : NormalCleanup;
4219   }
4220 
4221   // ARC primitives.
4222   void EmitARCInitWeak(Address addr, llvm::Value *value);
4223   void EmitARCDestroyWeak(Address addr);
4224   llvm::Value *EmitARCLoadWeak(Address addr);
4225   llvm::Value *EmitARCLoadWeakRetained(Address addr);
4226   llvm::Value *EmitARCStoreWeak(Address addr, llvm::Value *value, bool ignored);
4227   void emitARCCopyAssignWeak(QualType Ty, Address DstAddr, Address SrcAddr);
4228   void emitARCMoveAssignWeak(QualType Ty, Address DstAddr, Address SrcAddr);
4229   void EmitARCCopyWeak(Address dst, Address src);
4230   void EmitARCMoveWeak(Address dst, Address src);
4231   llvm::Value *EmitARCRetainAutorelease(QualType type, llvm::Value *value);
4232   llvm::Value *EmitARCRetainAutoreleaseNonBlock(llvm::Value *value);
4233   llvm::Value *EmitARCStoreStrong(LValue lvalue, llvm::Value *value,
4234                                   bool resultIgnored);
4235   llvm::Value *EmitARCStoreStrongCall(Address addr, llvm::Value *value,
4236                                       bool resultIgnored);
4237   llvm::Value *EmitARCRetain(QualType type, llvm::Value *value);
4238   llvm::Value *EmitARCRetainNonBlock(llvm::Value *value);
4239   llvm::Value *EmitARCRetainBlock(llvm::Value *value, bool mandatory);
4240   void EmitARCDestroyStrong(Address addr, ARCPreciseLifetime_t precise);
4241   void EmitARCRelease(llvm::Value *value, ARCPreciseLifetime_t precise);
4242   llvm::Value *EmitARCAutorelease(llvm::Value *value);
4243   llvm::Value *EmitARCAutoreleaseReturnValue(llvm::Value *value);
4244   llvm::Value *EmitARCRetainAutoreleaseReturnValue(llvm::Value *value);
4245   llvm::Value *EmitARCRetainAutoreleasedReturnValue(llvm::Value *value);
4246   llvm::Value *EmitARCUnsafeClaimAutoreleasedReturnValue(llvm::Value *value);
4247 
4248   llvm::Value *EmitObjCAutorelease(llvm::Value *value, llvm::Type *returnType);
4249   llvm::Value *EmitObjCRetainNonBlock(llvm::Value *value,
4250                                       llvm::Type *returnType);
4251   void EmitObjCRelease(llvm::Value *value, ARCPreciseLifetime_t precise);
4252 
4253   std::pair<LValue,llvm::Value*>
4254   EmitARCStoreAutoreleasing(const BinaryOperator *e);
4255   std::pair<LValue,llvm::Value*>
4256   EmitARCStoreStrong(const BinaryOperator *e, bool ignored);
4257   std::pair<LValue,llvm::Value*>
4258   EmitARCStoreUnsafeUnretained(const BinaryOperator *e, bool ignored);
4259 
4260   llvm::Value *EmitObjCAlloc(llvm::Value *value,
4261                              llvm::Type *returnType);
4262   llvm::Value *EmitObjCAllocWithZone(llvm::Value *value,
4263                                      llvm::Type *returnType);
4264   llvm::Value *EmitObjCAllocInit(llvm::Value *value, llvm::Type *resultType);
4265 
4266   llvm::Value *EmitObjCThrowOperand(const Expr *expr);
4267   llvm::Value *EmitObjCConsumeObject(QualType T, llvm::Value *Ptr);
4268   llvm::Value *EmitObjCExtendObjectLifetime(QualType T, llvm::Value *Ptr);
4269 
4270   llvm::Value *EmitARCExtendBlockObject(const Expr *expr);
4271   llvm::Value *EmitARCReclaimReturnedObject(const Expr *e,
4272                                             bool allowUnsafeClaim);
4273   llvm::Value *EmitARCRetainScalarExpr(const Expr *expr);
4274   llvm::Value *EmitARCRetainAutoreleaseScalarExpr(const Expr *expr);
4275   llvm::Value *EmitARCUnsafeUnretainedScalarExpr(const Expr *expr);
4276 
4277   void EmitARCIntrinsicUse(ArrayRef<llvm::Value*> values);
4278 
4279   void EmitARCNoopIntrinsicUse(ArrayRef<llvm::Value *> values);
4280 
4281   static Destroyer destroyARCStrongImprecise;
4282   static Destroyer destroyARCStrongPrecise;
4283   static Destroyer destroyARCWeak;
4284   static Destroyer emitARCIntrinsicUse;
4285   static Destroyer destroyNonTrivialCStruct;
4286 
4287   void EmitObjCAutoreleasePoolPop(llvm::Value *Ptr);
4288   llvm::Value *EmitObjCAutoreleasePoolPush();
4289   llvm::Value *EmitObjCMRRAutoreleasePoolPush();
4290   void EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr);
4291   void EmitObjCMRRAutoreleasePoolPop(llvm::Value *Ptr);
4292 
4293   /// Emits a reference binding to the passed in expression.
4294   RValue EmitReferenceBindingToExpr(const Expr *E);
4295 
4296   //===--------------------------------------------------------------------===//
4297   //                           Expression Emission
4298   //===--------------------------------------------------------------------===//
4299 
4300   // Expressions are broken into three classes: scalar, complex, aggregate.
4301 
4302   /// EmitScalarExpr - Emit the computation of the specified expression of LLVM
4303   /// scalar type, returning the result.
4304   llvm::Value *EmitScalarExpr(const Expr *E , bool IgnoreResultAssign = false);
4305 
4306   /// Emit a conversion from the specified type to the specified destination
4307   /// type, both of which are LLVM scalar types.
4308   llvm::Value *EmitScalarConversion(llvm::Value *Src, QualType SrcTy,
4309                                     QualType DstTy, SourceLocation Loc);
4310 
4311   /// Emit a conversion from the specified complex type to the specified
4312   /// destination type, where the destination type is an LLVM scalar type.
4313   llvm::Value *EmitComplexToScalarConversion(ComplexPairTy Src, QualType SrcTy,
4314                                              QualType DstTy,
4315                                              SourceLocation Loc);
4316 
4317   /// EmitAggExpr - Emit the computation of the specified expression
4318   /// of aggregate type.  The result is computed into the given slot,
4319   /// which may be null to indicate that the value is not needed.
4320   void EmitAggExpr(const Expr *E, AggValueSlot AS);
4321 
4322   /// EmitAggExprToLValue - Emit the computation of the specified expression of
4323   /// aggregate type into a temporary LValue.
4324   LValue EmitAggExprToLValue(const Expr *E);
4325 
4326   /// Build all the stores needed to initialize an aggregate at Dest with the
4327   /// value Val.
4328   void EmitAggregateStore(llvm::Value *Val, Address Dest, bool DestIsVolatile);
4329 
4330   /// EmitExtendGCLifetime - Given a pointer to an Objective-C object,
4331   /// make sure it survives garbage collection until this point.
4332   void EmitExtendGCLifetime(llvm::Value *object);
4333 
4334   /// EmitComplexExpr - Emit the computation of the specified expression of
4335   /// complex type, returning the result.
4336   ComplexPairTy EmitComplexExpr(const Expr *E,
4337                                 bool IgnoreReal = false,
4338                                 bool IgnoreImag = false);
4339 
4340   /// EmitComplexExprIntoLValue - Emit the given expression of complex
4341   /// type and place its result into the specified l-value.
4342   void EmitComplexExprIntoLValue(const Expr *E, LValue dest, bool isInit);
4343 
4344   /// EmitStoreOfComplex - Store a complex number into the specified l-value.
4345   void EmitStoreOfComplex(ComplexPairTy V, LValue dest, bool isInit);
4346 
4347   /// EmitLoadOfComplex - Load a complex number from the specified l-value.
4348   ComplexPairTy EmitLoadOfComplex(LValue src, SourceLocation loc);
4349 
4350   Address emitAddrOfRealComponent(Address complex, QualType complexType);
4351   Address emitAddrOfImagComponent(Address complex, QualType complexType);
4352 
4353   /// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
4354   /// global variable that has already been created for it.  If the initializer
4355   /// has a different type than GV does, this may free GV and return a different
4356   /// one.  Otherwise it just returns GV.
4357   llvm::GlobalVariable *
4358   AddInitializerToStaticVarDecl(const VarDecl &D,
4359                                 llvm::GlobalVariable *GV);
4360 
4361   // Emit an @llvm.invariant.start call for the given memory region.
4362   void EmitInvariantStart(llvm::Constant *Addr, CharUnits Size);
4363 
4364   /// EmitCXXGlobalVarDeclInit - Create the initializer for a C++
4365   /// variable with global storage.
4366   void EmitCXXGlobalVarDeclInit(const VarDecl &D, llvm::Constant *DeclPtr,
4367                                 bool PerformInit);
4368 
4369   llvm::Function *createAtExitStub(const VarDecl &VD, llvm::FunctionCallee Dtor,
4370                                    llvm::Constant *Addr);
4371 
4372   llvm::Function *createTLSAtExitStub(const VarDecl &VD,
4373                                       llvm::FunctionCallee Dtor,
4374                                       llvm::Constant *Addr,
4375                                       llvm::FunctionCallee &AtExit);
4376 
4377   /// Call atexit() with a function that passes the given argument to
4378   /// the given function.
4379   void registerGlobalDtorWithAtExit(const VarDecl &D, llvm::FunctionCallee fn,
4380                                     llvm::Constant *addr);
4381 
4382   /// Call atexit() with function dtorStub.
4383   void registerGlobalDtorWithAtExit(llvm::Constant *dtorStub);
4384 
4385   /// Call unatexit() with function dtorStub.
4386   llvm::Value *unregisterGlobalDtorWithUnAtExit(llvm::Constant *dtorStub);
4387 
4388   /// Emit code in this function to perform a guarded variable
4389   /// initialization.  Guarded initializations are used when it's not
4390   /// possible to prove that an initialization will be done exactly
4391   /// once, e.g. with a static local variable or a static data member
4392   /// of a class template.
4393   void EmitCXXGuardedInit(const VarDecl &D, llvm::GlobalVariable *DeclPtr,
4394                           bool PerformInit);
4395 
4396   enum class GuardKind { VariableGuard, TlsGuard };
4397 
4398   /// Emit a branch to select whether or not to perform guarded initialization.
4399   void EmitCXXGuardedInitBranch(llvm::Value *NeedsInit,
4400                                 llvm::BasicBlock *InitBlock,
4401                                 llvm::BasicBlock *NoInitBlock,
4402                                 GuardKind Kind, const VarDecl *D);
4403 
4404   /// GenerateCXXGlobalInitFunc - Generates code for initializing global
4405   /// variables.
4406   void
4407   GenerateCXXGlobalInitFunc(llvm::Function *Fn,
4408                             ArrayRef<llvm::Function *> CXXThreadLocals,
4409                             ConstantAddress Guard = ConstantAddress::invalid());
4410 
4411   /// GenerateCXXGlobalCleanUpFunc - Generates code for cleaning up global
4412   /// variables.
4413   void GenerateCXXGlobalCleanUpFunc(
4414       llvm::Function *Fn,
4415       ArrayRef<std::tuple<llvm::FunctionType *, llvm::WeakTrackingVH,
4416                           llvm::Constant *>>
4417           DtorsOrStermFinalizers);
4418 
4419   void GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn,
4420                                         const VarDecl *D,
4421                                         llvm::GlobalVariable *Addr,
4422                                         bool PerformInit);
4423 
4424   void EmitCXXConstructExpr(const CXXConstructExpr *E, AggValueSlot Dest);
4425 
4426   void EmitSynthesizedCXXCopyCtor(Address Dest, Address Src, const Expr *Exp);
4427 
4428   void EmitCXXThrowExpr(const CXXThrowExpr *E, bool KeepInsertionPoint = true);
4429 
4430   RValue EmitAtomicExpr(AtomicExpr *E);
4431 
4432   //===--------------------------------------------------------------------===//
4433   //                         Annotations Emission
4434   //===--------------------------------------------------------------------===//
4435 
4436   /// Emit an annotation call (intrinsic).
4437   llvm::Value *EmitAnnotationCall(llvm::Function *AnnotationFn,
4438                                   llvm::Value *AnnotatedVal,
4439                                   StringRef AnnotationStr,
4440                                   SourceLocation Location,
4441                                   const AnnotateAttr *Attr);
4442 
4443   /// Emit local annotations for the local variable V, declared by D.
4444   void EmitVarAnnotations(const VarDecl *D, llvm::Value *V);
4445 
4446   /// Emit field annotations for the given field & value. Returns the
4447   /// annotation result.
4448   Address EmitFieldAnnotations(const FieldDecl *D, Address V);
4449 
4450   //===--------------------------------------------------------------------===//
4451   //                             Internal Helpers
4452   //===--------------------------------------------------------------------===//
4453 
4454   /// ContainsLabel - Return true if the statement contains a label in it.  If
4455   /// this statement is not executed normally, it not containing a label means
4456   /// that we can just remove the code.
4457   static bool ContainsLabel(const Stmt *S, bool IgnoreCaseStmts = false);
4458 
4459   /// containsBreak - Return true if the statement contains a break out of it.
4460   /// If the statement (recursively) contains a switch or loop with a break
4461   /// inside of it, this is fine.
4462   static bool containsBreak(const Stmt *S);
4463 
4464   /// Determine if the given statement might introduce a declaration into the
4465   /// current scope, by being a (possibly-labelled) DeclStmt.
4466   static bool mightAddDeclToScope(const Stmt *S);
4467 
4468   /// ConstantFoldsToSimpleInteger - If the specified expression does not fold
4469   /// to a constant, or if it does but contains a label, return false.  If it
4470   /// constant folds return true and set the boolean result in Result.
4471   bool ConstantFoldsToSimpleInteger(const Expr *Cond, bool &Result,
4472                                     bool AllowLabels = false);
4473 
4474   /// ConstantFoldsToSimpleInteger - If the specified expression does not fold
4475   /// to a constant, or if it does but contains a label, return false.  If it
4476   /// constant folds return true and set the folded value.
4477   bool ConstantFoldsToSimpleInteger(const Expr *Cond, llvm::APSInt &Result,
4478                                     bool AllowLabels = false);
4479 
4480   /// isInstrumentedCondition - Determine whether the given condition is an
4481   /// instrumentable condition (i.e. no "&&" or "||").
4482   static bool isInstrumentedCondition(const Expr *C);
4483 
4484   /// EmitBranchToCounterBlock - Emit a conditional branch to a new block that
4485   /// increments a profile counter based on the semantics of the given logical
4486   /// operator opcode.  This is used to instrument branch condition coverage
4487   /// for logical operators.
4488   void EmitBranchToCounterBlock(const Expr *Cond, BinaryOperator::Opcode LOp,
4489                                 llvm::BasicBlock *TrueBlock,
4490                                 llvm::BasicBlock *FalseBlock,
4491                                 uint64_t TrueCount = 0,
4492                                 Stmt::Likelihood LH = Stmt::LH_None,
4493                                 const Expr *CntrIdx = nullptr);
4494 
4495   /// EmitBranchOnBoolExpr - Emit a branch on a boolean condition (e.g. for an
4496   /// if statement) to the specified blocks.  Based on the condition, this might
4497   /// try to simplify the codegen of the conditional based on the branch.
4498   /// TrueCount should be the number of times we expect the condition to
4499   /// evaluate to true based on PGO data.
4500   void EmitBranchOnBoolExpr(const Expr *Cond, llvm::BasicBlock *TrueBlock,
4501                             llvm::BasicBlock *FalseBlock, uint64_t TrueCount,
4502                             Stmt::Likelihood LH = Stmt::LH_None);
4503 
4504   /// Given an assignment `*LHS = RHS`, emit a test that checks if \p RHS is
4505   /// nonnull, if \p LHS is marked _Nonnull.
4506   void EmitNullabilityCheck(LValue LHS, llvm::Value *RHS, SourceLocation Loc);
4507 
4508   /// An enumeration which makes it easier to specify whether or not an
4509   /// operation is a subtraction.
4510   enum { NotSubtraction = false, IsSubtraction = true };
4511 
4512   /// Same as IRBuilder::CreateInBoundsGEP, but additionally emits a check to
4513   /// detect undefined behavior when the pointer overflow sanitizer is enabled.
4514   /// \p SignedIndices indicates whether any of the GEP indices are signed.
4515   /// \p IsSubtraction indicates whether the expression used to form the GEP
4516   /// is a subtraction.
4517   llvm::Value *EmitCheckedInBoundsGEP(llvm::Value *Ptr,
4518                                       ArrayRef<llvm::Value *> IdxList,
4519                                       bool SignedIndices,
4520                                       bool IsSubtraction,
4521                                       SourceLocation Loc,
4522                                       const Twine &Name = "");
4523 
4524   /// Specifies which type of sanitizer check to apply when handling a
4525   /// particular builtin.
4526   enum BuiltinCheckKind {
4527     BCK_CTZPassedZero,
4528     BCK_CLZPassedZero,
4529   };
4530 
4531   /// Emits an argument for a call to a builtin. If the builtin sanitizer is
4532   /// enabled, a runtime check specified by \p Kind is also emitted.
4533   llvm::Value *EmitCheckedArgForBuiltin(const Expr *E, BuiltinCheckKind Kind);
4534 
4535   /// Emit a description of a type in a format suitable for passing to
4536   /// a runtime sanitizer handler.
4537   llvm::Constant *EmitCheckTypeDescriptor(QualType T);
4538 
4539   /// Convert a value into a format suitable for passing to a runtime
4540   /// sanitizer handler.
4541   llvm::Value *EmitCheckValue(llvm::Value *V);
4542 
4543   /// Emit a description of a source location in a format suitable for
4544   /// passing to a runtime sanitizer handler.
4545   llvm::Constant *EmitCheckSourceLocation(SourceLocation Loc);
4546 
4547   /// Create a basic block that will either trap or call a handler function in
4548   /// the UBSan runtime with the provided arguments, and create a conditional
4549   /// branch to it.
4550   void EmitCheck(ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
4551                  SanitizerHandler Check, ArrayRef<llvm::Constant *> StaticArgs,
4552                  ArrayRef<llvm::Value *> DynamicArgs);
4553 
4554   /// Emit a slow path cross-DSO CFI check which calls __cfi_slowpath
4555   /// if Cond if false.
4556   void EmitCfiSlowPathCheck(SanitizerMask Kind, llvm::Value *Cond,
4557                             llvm::ConstantInt *TypeId, llvm::Value *Ptr,
4558                             ArrayRef<llvm::Constant *> StaticArgs);
4559 
4560   /// Emit a reached-unreachable diagnostic if \p Loc is valid and runtime
4561   /// checking is enabled. Otherwise, just emit an unreachable instruction.
4562   void EmitUnreachable(SourceLocation Loc);
4563 
4564   /// Create a basic block that will call the trap intrinsic, and emit a
4565   /// conditional branch to it, for the -ftrapv checks.
4566   void EmitTrapCheck(llvm::Value *Checked, SanitizerHandler CheckHandlerID);
4567 
4568   /// Emit a call to trap or debugtrap and attach function attribute
4569   /// "trap-func-name" if specified.
4570   llvm::CallInst *EmitTrapCall(llvm::Intrinsic::ID IntrID);
4571 
4572   /// Emit a stub for the cross-DSO CFI check function.
4573   void EmitCfiCheckStub();
4574 
4575   /// Emit a cross-DSO CFI failure handling function.
4576   void EmitCfiCheckFail();
4577 
4578   /// Create a check for a function parameter that may potentially be
4579   /// declared as non-null.
4580   void EmitNonNullArgCheck(RValue RV, QualType ArgType, SourceLocation ArgLoc,
4581                            AbstractCallee AC, unsigned ParmNum);
4582 
4583   /// EmitCallArg - Emit a single call argument.
4584   void EmitCallArg(CallArgList &args, const Expr *E, QualType ArgType);
4585 
4586   /// EmitDelegateCallArg - We are performing a delegate call; that
4587   /// is, the current function is delegating to another one.  Produce
4588   /// a r-value suitable for passing the given parameter.
4589   void EmitDelegateCallArg(CallArgList &args, const VarDecl *param,
4590                            SourceLocation loc);
4591 
4592   /// SetFPAccuracy - Set the minimum required accuracy of the given floating
4593   /// point operation, expressed as the maximum relative error in ulp.
4594   void SetFPAccuracy(llvm::Value *Val, float Accuracy);
4595 
4596   /// Set the codegen fast-math flags.
4597   void SetFastMathFlags(FPOptions FPFeatures);
4598 
4599 private:
4600   llvm::MDNode *getRangeForLoadFromType(QualType Ty);
4601   void EmitReturnOfRValue(RValue RV, QualType Ty);
4602 
4603   void deferPlaceholderReplacement(llvm::Instruction *Old, llvm::Value *New);
4604 
4605   llvm::SmallVector<std::pair<llvm::WeakTrackingVH, llvm::Value *>, 4>
4606       DeferredReplacements;
4607 
4608   /// Set the address of a local variable.
4609   void setAddrOfLocalVar(const VarDecl *VD, Address Addr) {
4610     assert(!LocalDeclMap.count(VD) && "Decl already exists in LocalDeclMap!");
4611     LocalDeclMap.insert({VD, Addr});
4612   }
4613 
4614   /// ExpandTypeFromArgs - Reconstruct a structure of type \arg Ty
4615   /// from function arguments into \arg Dst. See ABIArgInfo::Expand.
4616   ///
4617   /// \param AI - The first function argument of the expansion.
4618   void ExpandTypeFromArgs(QualType Ty, LValue Dst,
4619                           llvm::Function::arg_iterator &AI);
4620 
4621   /// ExpandTypeToArgs - Expand an CallArg \arg Arg, with the LLVM type for \arg
4622   /// Ty, into individual arguments on the provided vector \arg IRCallArgs,
4623   /// starting at index \arg IRCallArgPos. See ABIArgInfo::Expand.
4624   void ExpandTypeToArgs(QualType Ty, CallArg Arg, llvm::FunctionType *IRFuncTy,
4625                         SmallVectorImpl<llvm::Value *> &IRCallArgs,
4626                         unsigned &IRCallArgPos);
4627 
4628   llvm::Value* EmitAsmInput(const TargetInfo::ConstraintInfo &Info,
4629                             const Expr *InputExpr, std::string &ConstraintStr);
4630 
4631   llvm::Value* EmitAsmInputLValue(const TargetInfo::ConstraintInfo &Info,
4632                                   LValue InputValue, QualType InputType,
4633                                   std::string &ConstraintStr,
4634                                   SourceLocation Loc);
4635 
4636   /// Attempts to statically evaluate the object size of E. If that
4637   /// fails, emits code to figure the size of E out for us. This is
4638   /// pass_object_size aware.
4639   ///
4640   /// If EmittedExpr is non-null, this will use that instead of re-emitting E.
4641   llvm::Value *evaluateOrEmitBuiltinObjectSize(const Expr *E, unsigned Type,
4642                                                llvm::IntegerType *ResType,
4643                                                llvm::Value *EmittedE,
4644                                                bool IsDynamic);
4645 
4646   /// Emits the size of E, as required by __builtin_object_size. This
4647   /// function is aware of pass_object_size parameters, and will act accordingly
4648   /// if E is a parameter with the pass_object_size attribute.
4649   llvm::Value *emitBuiltinObjectSize(const Expr *E, unsigned Type,
4650                                      llvm::IntegerType *ResType,
4651                                      llvm::Value *EmittedE,
4652                                      bool IsDynamic);
4653 
4654   void emitZeroOrPatternForAutoVarInit(QualType type, const VarDecl &D,
4655                                        Address Loc);
4656 
4657 public:
4658   enum class EvaluationOrder {
4659     ///! No language constraints on evaluation order.
4660     Default,
4661     ///! Language semantics require left-to-right evaluation.
4662     ForceLeftToRight,
4663     ///! Language semantics require right-to-left evaluation.
4664     ForceRightToLeft
4665   };
4666 
4667   // Wrapper for function prototype sources. Wraps either a FunctionProtoType or
4668   // an ObjCMethodDecl.
4669   struct PrototypeWrapper {
4670     llvm::PointerUnion<const FunctionProtoType *, const ObjCMethodDecl *> P;
4671 
4672     PrototypeWrapper(const FunctionProtoType *FT) : P(FT) {}
4673     PrototypeWrapper(const ObjCMethodDecl *MD) : P(MD) {}
4674   };
4675 
4676   void EmitCallArgs(CallArgList &Args, PrototypeWrapper Prototype,
4677                     llvm::iterator_range<CallExpr::const_arg_iterator> ArgRange,
4678                     AbstractCallee AC = AbstractCallee(),
4679                     unsigned ParamsToSkip = 0,
4680                     EvaluationOrder Order = EvaluationOrder::Default);
4681 
4682   /// EmitPointerWithAlignment - Given an expression with a pointer type,
4683   /// emit the value and compute our best estimate of the alignment of the
4684   /// pointee.
4685   ///
4686   /// \param BaseInfo - If non-null, this will be initialized with
4687   /// information about the source of the alignment and the may-alias
4688   /// attribute.  Note that this function will conservatively fall back on
4689   /// the type when it doesn't recognize the expression and may-alias will
4690   /// be set to false.
4691   ///
4692   /// One reasonable way to use this information is when there's a language
4693   /// guarantee that the pointer must be aligned to some stricter value, and
4694   /// we're simply trying to ensure that sufficiently obvious uses of under-
4695   /// aligned objects don't get miscompiled; for example, a placement new
4696   /// into the address of a local variable.  In such a case, it's quite
4697   /// reasonable to just ignore the returned alignment when it isn't from an
4698   /// explicit source.
4699   Address EmitPointerWithAlignment(const Expr *Addr,
4700                                    LValueBaseInfo *BaseInfo = nullptr,
4701                                    TBAAAccessInfo *TBAAInfo = nullptr);
4702 
4703   /// If \p E references a parameter with pass_object_size info or a constant
4704   /// array size modifier, emit the object size divided by the size of \p EltTy.
4705   /// Otherwise return null.
4706   llvm::Value *LoadPassedObjectSize(const Expr *E, QualType EltTy);
4707 
4708   void EmitSanitizerStatReport(llvm::SanitizerStatKind SSK);
4709 
4710   struct MultiVersionResolverOption {
4711     llvm::Function *Function;
4712     struct Conds {
4713       StringRef Architecture;
4714       llvm::SmallVector<StringRef, 8> Features;
4715 
4716       Conds(StringRef Arch, ArrayRef<StringRef> Feats)
4717           : Architecture(Arch), Features(Feats.begin(), Feats.end()) {}
4718     } Conditions;
4719 
4720     MultiVersionResolverOption(llvm::Function *F, StringRef Arch,
4721                                ArrayRef<StringRef> Feats)
4722         : Function(F), Conditions(Arch, Feats) {}
4723   };
4724 
4725   // Emits the body of a multiversion function's resolver. Assumes that the
4726   // options are already sorted in the proper order, with the 'default' option
4727   // last (if it exists).
4728   void EmitMultiVersionResolver(llvm::Function *Resolver,
4729                                 ArrayRef<MultiVersionResolverOption> Options);
4730 
4731   static uint64_t GetX86CpuSupportsMask(ArrayRef<StringRef> FeatureStrs);
4732 
4733 private:
4734   QualType getVarArgType(const Expr *Arg);
4735 
4736   void EmitDeclMetadata();
4737 
4738   BlockByrefHelpers *buildByrefHelpers(llvm::StructType &byrefType,
4739                                   const AutoVarEmission &emission);
4740 
4741   void AddObjCARCExceptionMetadata(llvm::Instruction *Inst);
4742 
4743   llvm::Value *GetValueForARMHint(unsigned BuiltinID);
4744   llvm::Value *EmitX86CpuIs(const CallExpr *E);
4745   llvm::Value *EmitX86CpuIs(StringRef CPUStr);
4746   llvm::Value *EmitX86CpuSupports(const CallExpr *E);
4747   llvm::Value *EmitX86CpuSupports(ArrayRef<StringRef> FeatureStrs);
4748   llvm::Value *EmitX86CpuSupports(uint64_t Mask);
4749   llvm::Value *EmitX86CpuInit();
4750   llvm::Value *FormResolverCondition(const MultiVersionResolverOption &RO);
4751 };
4752 
4753 /// TargetFeatures - This class is used to check whether the builtin function
4754 /// has the required tagert specific features. It is able to support the
4755 /// combination of ','(and), '|'(or), and '()'. By default, the priority of
4756 /// ',' is higher than that of '|' .
4757 /// E.g:
4758 /// A,B|C means the builtin function requires both A and B, or C.
4759 /// If we want the builtin function requires both A and B, or both A and C,
4760 /// there are two ways: A,B|A,C or A,(B|C).
4761 /// The FeaturesList should not contain spaces, and brackets must appear in
4762 /// pairs.
4763 class TargetFeatures {
4764   struct FeatureListStatus {
4765     bool HasFeatures;
4766     StringRef CurFeaturesList;
4767   };
4768 
4769   const llvm::StringMap<bool> &CallerFeatureMap;
4770 
4771   FeatureListStatus getAndFeatures(StringRef FeatureList) {
4772     int InParentheses = 0;
4773     bool HasFeatures = true;
4774     size_t SubexpressionStart = 0;
4775     for (size_t i = 0, e = FeatureList.size(); i < e; ++i) {
4776       char CurrentToken = FeatureList[i];
4777       switch (CurrentToken) {
4778       default:
4779         break;
4780       case '(':
4781         if (InParentheses == 0)
4782           SubexpressionStart = i + 1;
4783         ++InParentheses;
4784         break;
4785       case ')':
4786         --InParentheses;
4787         assert(InParentheses >= 0 && "Parentheses are not in pair");
4788         LLVM_FALLTHROUGH;
4789       case '|':
4790       case ',':
4791         if (InParentheses == 0) {
4792           if (HasFeatures && i != SubexpressionStart) {
4793             StringRef F = FeatureList.slice(SubexpressionStart, i);
4794             HasFeatures = CurrentToken == ')' ? hasRequiredFeatures(F)
4795                                               : CallerFeatureMap.lookup(F);
4796           }
4797           SubexpressionStart = i + 1;
4798           if (CurrentToken == '|') {
4799             return {HasFeatures, FeatureList.substr(SubexpressionStart)};
4800           }
4801         }
4802         break;
4803       }
4804     }
4805     assert(InParentheses == 0 && "Parentheses are not in pair");
4806     if (HasFeatures && SubexpressionStart != FeatureList.size())
4807       HasFeatures =
4808           CallerFeatureMap.lookup(FeatureList.substr(SubexpressionStart));
4809     return {HasFeatures, StringRef()};
4810   }
4811 
4812 public:
4813   bool hasRequiredFeatures(StringRef FeatureList) {
4814     FeatureListStatus FS = {false, FeatureList};
4815     while (!FS.HasFeatures && !FS.CurFeaturesList.empty())
4816       FS = getAndFeatures(FS.CurFeaturesList);
4817     return FS.HasFeatures;
4818   }
4819 
4820   TargetFeatures(const llvm::StringMap<bool> &CallerFeatureMap)
4821       : CallerFeatureMap(CallerFeatureMap) {}
4822 };
4823 
4824 inline DominatingLLVMValue::saved_type
4825 DominatingLLVMValue::save(CodeGenFunction &CGF, llvm::Value *value) {
4826   if (!needsSaving(value)) return saved_type(value, false);
4827 
4828   // Otherwise, we need an alloca.
4829   auto align = CharUnits::fromQuantity(
4830             CGF.CGM.getDataLayout().getPrefTypeAlignment(value->getType()));
4831   Address alloca =
4832     CGF.CreateTempAlloca(value->getType(), align, "cond-cleanup.save");
4833   CGF.Builder.CreateStore(value, alloca);
4834 
4835   return saved_type(alloca.getPointer(), true);
4836 }
4837 
4838 inline llvm::Value *DominatingLLVMValue::restore(CodeGenFunction &CGF,
4839                                                  saved_type value) {
4840   // If the value says it wasn't saved, trust that it's still dominating.
4841   if (!value.getInt()) return value.getPointer();
4842 
4843   // Otherwise, it should be an alloca instruction, as set up in save().
4844   auto alloca = cast<llvm::AllocaInst>(value.getPointer());
4845   return CGF.Builder.CreateAlignedLoad(alloca->getAllocatedType(), alloca,
4846                                        alloca->getAlign());
4847 }
4848 
4849 }  // end namespace CodeGen
4850 
4851 // Map the LangOption for floating point exception behavior into
4852 // the corresponding enum in the IR.
4853 llvm::fp::ExceptionBehavior
4854 ToConstrainedExceptMD(LangOptions::FPExceptionModeKind Kind);
4855 }  // end namespace clang
4856 
4857 #endif
4858