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/Type.h"
30 #include "clang/Basic/ABI.h"
31 #include "clang/Basic/CapturedStmt.h"
32 #include "clang/Basic/CodeGenOptions.h"
33 #include "clang/Basic/OpenMPKinds.h"
34 #include "clang/Basic/TargetInfo.h"
35 #include "llvm/ADT/ArrayRef.h"
36 #include "llvm/ADT/DenseMap.h"
37 #include "llvm/ADT/MapVector.h"
38 #include "llvm/ADT/SmallVector.h"
39 #include "llvm/Frontend/OpenMP/OMPIRBuilder.h"
40 #include "llvm/IR/ValueHandle.h"
41 #include "llvm/Support/Debug.h"
42 #include "llvm/Transforms/Utils/SanitizerStats.h"
43 
44 namespace llvm {
45 class BasicBlock;
46 class LLVMContext;
47 class MDNode;
48 class Module;
49 class SwitchInst;
50 class Twine;
51 class Value;
52 }
53 
54 namespace clang {
55 class ASTContext;
56 class BlockDecl;
57 class CXXDestructorDecl;
58 class CXXForRangeStmt;
59 class CXXTryStmt;
60 class Decl;
61 class LabelDecl;
62 class EnumConstantDecl;
63 class FunctionDecl;
64 class FunctionProtoType;
65 class LabelStmt;
66 class ObjCContainerDecl;
67 class ObjCInterfaceDecl;
68 class ObjCIvarDecl;
69 class ObjCMethodDecl;
70 class ObjCImplementationDecl;
71 class ObjCPropertyImplDecl;
72 class TargetInfo;
73 class VarDecl;
74 class ObjCForCollectionStmt;
75 class ObjCAtTryStmt;
76 class ObjCAtThrowStmt;
77 class ObjCAtSynchronizedStmt;
78 class ObjCAutoreleasePoolStmt;
79 class ReturnsNonNullAttr;
80 class SVETypeFlags;
81 
82 namespace analyze_os_log {
83 class OSLogBufferLayout;
84 }
85 
86 namespace CodeGen {
87 class CodeGenTypes;
88 class CGCallee;
89 class CGFunctionInfo;
90 class CGRecordLayout;
91 class CGBlockInfo;
92 class CGCXXABI;
93 class BlockByrefHelpers;
94 class BlockByrefInfo;
95 class BlockFlags;
96 class BlockFieldFlags;
97 class RegionCodeGenTy;
98 class TargetCodeGenInfo;
99 struct OMPTaskDataTy;
100 struct CGCoroData;
101 
102 /// The kind of evaluation to perform on values of a particular
103 /// type.  Basically, is the code in CGExprScalar, CGExprComplex, or
104 /// CGExprAgg?
105 ///
106 /// TODO: should vectors maybe be split out into their own thing?
107 enum TypeEvaluationKind {
108   TEK_Scalar,
109   TEK_Complex,
110   TEK_Aggregate
111 };
112 
113 #define LIST_SANITIZER_CHECKS                                                  \
114   SANITIZER_CHECK(AddOverflow, add_overflow, 0)                                \
115   SANITIZER_CHECK(BuiltinUnreachable, builtin_unreachable, 0)                  \
116   SANITIZER_CHECK(CFICheckFail, cfi_check_fail, 0)                             \
117   SANITIZER_CHECK(DivremOverflow, divrem_overflow, 0)                          \
118   SANITIZER_CHECK(DynamicTypeCacheMiss, dynamic_type_cache_miss, 0)            \
119   SANITIZER_CHECK(FloatCastOverflow, float_cast_overflow, 0)                   \
120   SANITIZER_CHECK(FunctionTypeMismatch, function_type_mismatch, 1)             \
121   SANITIZER_CHECK(ImplicitConversion, implicit_conversion, 0)                  \
122   SANITIZER_CHECK(InvalidBuiltin, invalid_builtin, 0)                          \
123   SANITIZER_CHECK(LoadInvalidValue, load_invalid_value, 0)                     \
124   SANITIZER_CHECK(MissingReturn, missing_return, 0)                            \
125   SANITIZER_CHECK(MulOverflow, mul_overflow, 0)                                \
126   SANITIZER_CHECK(NegateOverflow, negate_overflow, 0)                          \
127   SANITIZER_CHECK(NullabilityArg, nullability_arg, 0)                          \
128   SANITIZER_CHECK(NullabilityReturn, nullability_return, 1)                    \
129   SANITIZER_CHECK(NonnullArg, nonnull_arg, 0)                                  \
130   SANITIZER_CHECK(NonnullReturn, nonnull_return, 1)                            \
131   SANITIZER_CHECK(OutOfBounds, out_of_bounds, 0)                               \
132   SANITIZER_CHECK(PointerOverflow, pointer_overflow, 0)                        \
133   SANITIZER_CHECK(ShiftOutOfBounds, shift_out_of_bounds, 0)                    \
134   SANITIZER_CHECK(SubOverflow, sub_overflow, 0)                                \
135   SANITIZER_CHECK(TypeMismatch, type_mismatch, 1)                              \
136   SANITIZER_CHECK(AlignmentAssumption, alignment_assumption, 0)                \
137   SANITIZER_CHECK(VLABoundNotPositive, vla_bound_not_positive, 0)
138 
139 enum SanitizerHandler {
140 #define SANITIZER_CHECK(Enum, Name, Version) Enum,
141   LIST_SANITIZER_CHECKS
142 #undef SANITIZER_CHECK
143 };
144 
145 /// Helper class with most of the code for saving a value for a
146 /// conditional expression cleanup.
147 struct DominatingLLVMValue {
148   typedef llvm::PointerIntPair<llvm::Value*, 1, bool> saved_type;
149 
150   /// Answer whether the given value needs extra work to be saved.
151   static bool needsSaving(llvm::Value *value) {
152     // If it's not an instruction, we don't need to save.
153     if (!isa<llvm::Instruction>(value)) return false;
154 
155     // If it's an instruction in the entry block, we don't need to save.
156     llvm::BasicBlock *block = cast<llvm::Instruction>(value)->getParent();
157     return (block != &block->getParent()->getEntryBlock());
158   }
159 
160   static saved_type save(CodeGenFunction &CGF, llvm::Value *value);
161   static llvm::Value *restore(CodeGenFunction &CGF, saved_type value);
162 };
163 
164 /// A partial specialization of DominatingValue for llvm::Values that
165 /// might be llvm::Instructions.
166 template <class T> struct DominatingPointer<T,true> : DominatingLLVMValue {
167   typedef T *type;
168   static type restore(CodeGenFunction &CGF, saved_type value) {
169     return static_cast<T*>(DominatingLLVMValue::restore(CGF, value));
170   }
171 };
172 
173 /// A specialization of DominatingValue for Address.
174 template <> struct DominatingValue<Address> {
175   typedef Address type;
176 
177   struct saved_type {
178     DominatingLLVMValue::saved_type SavedValue;
179     CharUnits Alignment;
180   };
181 
182   static bool needsSaving(type value) {
183     return DominatingLLVMValue::needsSaving(value.getPointer());
184   }
185   static saved_type save(CodeGenFunction &CGF, type value) {
186     return { DominatingLLVMValue::save(CGF, value.getPointer()),
187              value.getAlignment() };
188   }
189   static type restore(CodeGenFunction &CGF, saved_type value) {
190     return Address(DominatingLLVMValue::restore(CGF, value.SavedValue),
191                    value.Alignment);
192   }
193 };
194 
195 /// A specialization of DominatingValue for RValue.
196 template <> struct DominatingValue<RValue> {
197   typedef RValue type;
198   class saved_type {
199     enum Kind { ScalarLiteral, ScalarAddress, AggregateLiteral,
200                 AggregateAddress, ComplexAddress };
201 
202     llvm::Value *Value;
203     unsigned K : 3;
204     unsigned Align : 29;
205     saved_type(llvm::Value *v, Kind k, unsigned a = 0)
206       : Value(v), K(k), Align(a) {}
207 
208   public:
209     static bool needsSaving(RValue value);
210     static saved_type save(CodeGenFunction &CGF, RValue value);
211     RValue restore(CodeGenFunction &CGF);
212 
213     // implementations in CGCleanup.cpp
214   };
215 
216   static bool needsSaving(type value) {
217     return saved_type::needsSaving(value);
218   }
219   static saved_type save(CodeGenFunction &CGF, type value) {
220     return saved_type::save(CGF, value);
221   }
222   static type restore(CodeGenFunction &CGF, saved_type value) {
223     return value.restore(CGF);
224   }
225 };
226 
227 /// CodeGenFunction - This class organizes the per-function state that is used
228 /// while generating LLVM code.
229 class CodeGenFunction : public CodeGenTypeCache {
230   CodeGenFunction(const CodeGenFunction &) = delete;
231   void operator=(const CodeGenFunction &) = delete;
232 
233   friend class CGCXXABI;
234 public:
235   /// A jump destination is an abstract label, branching to which may
236   /// require a jump out through normal cleanups.
237   struct JumpDest {
238     JumpDest() : Block(nullptr), ScopeDepth(), Index(0) {}
239     JumpDest(llvm::BasicBlock *Block,
240              EHScopeStack::stable_iterator Depth,
241              unsigned Index)
242       : Block(Block), ScopeDepth(Depth), Index(Index) {}
243 
244     bool isValid() const { return Block != nullptr; }
245     llvm::BasicBlock *getBlock() const { return Block; }
246     EHScopeStack::stable_iterator getScopeDepth() const { return ScopeDepth; }
247     unsigned getDestIndex() const { return Index; }
248 
249     // This should be used cautiously.
250     void setScopeDepth(EHScopeStack::stable_iterator depth) {
251       ScopeDepth = depth;
252     }
253 
254   private:
255     llvm::BasicBlock *Block;
256     EHScopeStack::stable_iterator ScopeDepth;
257     unsigned Index;
258   };
259 
260   // Helper class for the OpenMP IR Builder. Allows reusability of code used for
261   // region body, and finalization codegen callbacks. This will class will also
262   // contain privatization functions used by the privatization call backs
263   struct OMPBuilderCBHelpers {
264 
265     using InsertPointTy = llvm::OpenMPIRBuilder::InsertPointTy;
266 
267     /// Emit the Finalization for an OMP region
268     /// \param CGF	The Codegen function this belongs to
269     /// \param IP	Insertion point for generating the finalization code.
270     static void FinalizeOMPRegion(CodeGenFunction &CGF, InsertPointTy IP) {
271       CGBuilderTy::InsertPointGuard IPG(CGF.Builder);
272       assert(IP.getBlock()->end() != IP.getPoint() &&
273              "OpenMP IR Builder should cause terminated block!");
274 
275       llvm::BasicBlock *IPBB = IP.getBlock();
276       llvm::BasicBlock *DestBB = IPBB->getUniqueSuccessor();
277       assert(DestBB && "Finalization block should have one successor!");
278 
279       // erase and replace with cleanup branch.
280       IPBB->getTerminator()->eraseFromParent();
281       CGF.Builder.SetInsertPoint(IPBB);
282       CodeGenFunction::JumpDest Dest = CGF.getJumpDestInCurrentScope(DestBB);
283       CGF.EmitBranchThroughCleanup(Dest);
284     }
285 
286     /// Emit the body of an OMP region
287     /// \param CGF	The Codegen function this belongs to
288     /// \param RegionBodyStmt	The body statement for the OpenMP region being
289     /// 			 generated
290     /// \param CodeGenIP	Insertion point for generating the body code.
291     /// \param FiniBB	The finalization basic block
292     static void EmitOMPRegionBody(CodeGenFunction &CGF,
293                                   const Stmt *RegionBodyStmt,
294                                   InsertPointTy CodeGenIP,
295                                   llvm::BasicBlock &FiniBB) {
296       llvm::BasicBlock *CodeGenIPBB = CodeGenIP.getBlock();
297       if (llvm::Instruction *CodeGenIPBBTI = CodeGenIPBB->getTerminator())
298         CodeGenIPBBTI->eraseFromParent();
299 
300       CGF.Builder.SetInsertPoint(CodeGenIPBB);
301 
302       CGF.EmitStmt(RegionBodyStmt);
303 
304       if (CGF.Builder.saveIP().isSet())
305         CGF.Builder.CreateBr(&FiniBB);
306     }
307 
308     /// RAII for preserving necessary info during Outlined region body codegen.
309     class OutlinedRegionBodyRAII {
310 
311       llvm::AssertingVH<llvm::Instruction> OldAllocaIP;
312       CodeGenFunction::JumpDest OldReturnBlock;
313       CodeGenFunction &CGF;
314 
315     public:
316       OutlinedRegionBodyRAII(CodeGenFunction &cgf, InsertPointTy &AllocaIP,
317                              llvm::BasicBlock &RetBB)
318           : CGF(cgf) {
319         assert(AllocaIP.isSet() &&
320                "Must specify Insertion point for allocas of outlined function");
321         OldAllocaIP = CGF.AllocaInsertPt;
322         CGF.AllocaInsertPt = &*AllocaIP.getPoint();
323 
324         OldReturnBlock = CGF.ReturnBlock;
325         CGF.ReturnBlock = CGF.getJumpDestInCurrentScope(&RetBB);
326       }
327 
328       ~OutlinedRegionBodyRAII() {
329         CGF.AllocaInsertPt = OldAllocaIP;
330         CGF.ReturnBlock = OldReturnBlock;
331       }
332     };
333 
334     /// RAII for preserving necessary info during inlined region body codegen.
335     class InlinedRegionBodyRAII {
336 
337       llvm::AssertingVH<llvm::Instruction> OldAllocaIP;
338       CodeGenFunction &CGF;
339 
340     public:
341       InlinedRegionBodyRAII(CodeGenFunction &cgf, InsertPointTy &AllocaIP,
342                             llvm::BasicBlock &FiniBB)
343           : CGF(cgf) {
344         // Alloca insertion block should be in the entry block of the containing
345         // function so it expects an empty AllocaIP in which case will reuse the
346         // old alloca insertion point, or a new AllocaIP in the same block as
347         // the old one
348         assert((!AllocaIP.isSet() ||
349                 CGF.AllocaInsertPt->getParent() == AllocaIP.getBlock()) &&
350                "Insertion point should be in the entry block of containing "
351                "function!");
352         OldAllocaIP = CGF.AllocaInsertPt;
353         if (AllocaIP.isSet())
354           CGF.AllocaInsertPt = &*AllocaIP.getPoint();
355 
356         // TODO: Remove the call, after making sure the counter is not used by
357         //       the EHStack.
358         // Since this is an inlined region, it should not modify the
359         // ReturnBlock, and should reuse the one for the enclosing outlined
360         // region. So, the JumpDest being return by the function is discarded
361         (void)CGF.getJumpDestInCurrentScope(&FiniBB);
362       }
363 
364       ~InlinedRegionBodyRAII() { CGF.AllocaInsertPt = OldAllocaIP; }
365     };
366   };
367 
368   CodeGenModule &CGM;  // Per-module state.
369   const TargetInfo &Target;
370 
371   typedef std::pair<llvm::Value *, llvm::Value *> ComplexPairTy;
372   LoopInfoStack LoopStack;
373   CGBuilderTy Builder;
374 
375   // Stores variables for which we can't generate correct lifetime markers
376   // because of jumps.
377   VarBypassDetector Bypasses;
378 
379   // CodeGen lambda for loops and support for ordered clause
380   typedef llvm::function_ref<void(CodeGenFunction &, const OMPLoopDirective &,
381                                   JumpDest)>
382       CodeGenLoopTy;
383   typedef llvm::function_ref<void(CodeGenFunction &, SourceLocation,
384                                   const unsigned, const bool)>
385       CodeGenOrderedTy;
386 
387   // Codegen lambda for loop bounds in worksharing loop constructs
388   typedef llvm::function_ref<std::pair<LValue, LValue>(
389       CodeGenFunction &, const OMPExecutableDirective &S)>
390       CodeGenLoopBoundsTy;
391 
392   // Codegen lambda for loop bounds in dispatch-based loop implementation
393   typedef llvm::function_ref<std::pair<llvm::Value *, llvm::Value *>(
394       CodeGenFunction &, const OMPExecutableDirective &S, Address LB,
395       Address UB)>
396       CodeGenDispatchBoundsTy;
397 
398   /// CGBuilder insert helper. This function is called after an
399   /// instruction is created using Builder.
400   void InsertHelper(llvm::Instruction *I, const llvm::Twine &Name,
401                     llvm::BasicBlock *BB,
402                     llvm::BasicBlock::iterator InsertPt) const;
403 
404   /// CurFuncDecl - Holds the Decl for the current outermost
405   /// non-closure context.
406   const Decl *CurFuncDecl;
407   /// CurCodeDecl - This is the inner-most code context, which includes blocks.
408   const Decl *CurCodeDecl;
409   const CGFunctionInfo *CurFnInfo;
410   QualType FnRetTy;
411   llvm::Function *CurFn = nullptr;
412 
413   // Holds coroutine data if the current function is a coroutine. We use a
414   // wrapper to manage its lifetime, so that we don't have to define CGCoroData
415   // in this header.
416   struct CGCoroInfo {
417     std::unique_ptr<CGCoroData> Data;
418     CGCoroInfo();
419     ~CGCoroInfo();
420   };
421   CGCoroInfo CurCoro;
422 
423   bool isCoroutine() const {
424     return CurCoro.Data != nullptr;
425   }
426 
427   /// CurGD - The GlobalDecl for the current function being compiled.
428   GlobalDecl CurGD;
429 
430   /// PrologueCleanupDepth - The cleanup depth enclosing all the
431   /// cleanups associated with the parameters.
432   EHScopeStack::stable_iterator PrologueCleanupDepth;
433 
434   /// ReturnBlock - Unified return block.
435   JumpDest ReturnBlock;
436 
437   /// ReturnValue - The temporary alloca to hold the return
438   /// value. This is invalid iff the function has no return value.
439   Address ReturnValue = Address::invalid();
440 
441   /// ReturnValuePointer - The temporary alloca to hold a pointer to sret.
442   /// This is invalid if sret is not in use.
443   Address ReturnValuePointer = Address::invalid();
444 
445   /// Return true if a label was seen in the current scope.
446   bool hasLabelBeenSeenInCurrentScope() const {
447     if (CurLexicalScope)
448       return CurLexicalScope->hasLabels();
449     return !LabelMap.empty();
450   }
451 
452   /// AllocaInsertPoint - This is an instruction in the entry block before which
453   /// we prefer to insert allocas.
454   llvm::AssertingVH<llvm::Instruction> AllocaInsertPt;
455 
456   /// API for captured statement code generation.
457   class CGCapturedStmtInfo {
458   public:
459     explicit CGCapturedStmtInfo(CapturedRegionKind K = CR_Default)
460         : Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {}
461     explicit CGCapturedStmtInfo(const CapturedStmt &S,
462                                 CapturedRegionKind K = CR_Default)
463       : Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {
464 
465       RecordDecl::field_iterator Field =
466         S.getCapturedRecordDecl()->field_begin();
467       for (CapturedStmt::const_capture_iterator I = S.capture_begin(),
468                                                 E = S.capture_end();
469            I != E; ++I, ++Field) {
470         if (I->capturesThis())
471           CXXThisFieldDecl = *Field;
472         else if (I->capturesVariable())
473           CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
474         else if (I->capturesVariableByCopy())
475           CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
476       }
477     }
478 
479     virtual ~CGCapturedStmtInfo();
480 
481     CapturedRegionKind getKind() const { return Kind; }
482 
483     virtual void setContextValue(llvm::Value *V) { ThisValue = V; }
484     // Retrieve the value of the context parameter.
485     virtual llvm::Value *getContextValue() const { return ThisValue; }
486 
487     /// Lookup the captured field decl for a variable.
488     virtual const FieldDecl *lookup(const VarDecl *VD) const {
489       return CaptureFields.lookup(VD->getCanonicalDecl());
490     }
491 
492     bool isCXXThisExprCaptured() const { return getThisFieldDecl() != nullptr; }
493     virtual FieldDecl *getThisFieldDecl() const { return CXXThisFieldDecl; }
494 
495     static bool classof(const CGCapturedStmtInfo *) {
496       return true;
497     }
498 
499     /// Emit the captured statement body.
500     virtual void EmitBody(CodeGenFunction &CGF, const Stmt *S) {
501       CGF.incrementProfileCounter(S);
502       CGF.EmitStmt(S);
503     }
504 
505     /// Get the name of the capture helper.
506     virtual StringRef getHelperName() const { return "__captured_stmt"; }
507 
508   private:
509     /// The kind of captured statement being generated.
510     CapturedRegionKind Kind;
511 
512     /// Keep the map between VarDecl and FieldDecl.
513     llvm::SmallDenseMap<const VarDecl *, FieldDecl *> CaptureFields;
514 
515     /// The base address of the captured record, passed in as the first
516     /// argument of the parallel region function.
517     llvm::Value *ThisValue;
518 
519     /// Captured 'this' type.
520     FieldDecl *CXXThisFieldDecl;
521   };
522   CGCapturedStmtInfo *CapturedStmtInfo = nullptr;
523 
524   /// RAII for correct setting/restoring of CapturedStmtInfo.
525   class CGCapturedStmtRAII {
526   private:
527     CodeGenFunction &CGF;
528     CGCapturedStmtInfo *PrevCapturedStmtInfo;
529   public:
530     CGCapturedStmtRAII(CodeGenFunction &CGF,
531                        CGCapturedStmtInfo *NewCapturedStmtInfo)
532         : CGF(CGF), PrevCapturedStmtInfo(CGF.CapturedStmtInfo) {
533       CGF.CapturedStmtInfo = NewCapturedStmtInfo;
534     }
535     ~CGCapturedStmtRAII() { CGF.CapturedStmtInfo = PrevCapturedStmtInfo; }
536   };
537 
538   /// An abstract representation of regular/ObjC call/message targets.
539   class AbstractCallee {
540     /// The function declaration of the callee.
541     const Decl *CalleeDecl;
542 
543   public:
544     AbstractCallee() : CalleeDecl(nullptr) {}
545     AbstractCallee(const FunctionDecl *FD) : CalleeDecl(FD) {}
546     AbstractCallee(const ObjCMethodDecl *OMD) : CalleeDecl(OMD) {}
547     bool hasFunctionDecl() const {
548       return dyn_cast_or_null<FunctionDecl>(CalleeDecl);
549     }
550     const Decl *getDecl() const { return CalleeDecl; }
551     unsigned getNumParams() const {
552       if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
553         return FD->getNumParams();
554       return cast<ObjCMethodDecl>(CalleeDecl)->param_size();
555     }
556     const ParmVarDecl *getParamDecl(unsigned I) const {
557       if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
558         return FD->getParamDecl(I);
559       return *(cast<ObjCMethodDecl>(CalleeDecl)->param_begin() + I);
560     }
561   };
562 
563   /// Sanitizers enabled for this function.
564   SanitizerSet SanOpts;
565 
566   /// True if CodeGen currently emits code implementing sanitizer checks.
567   bool IsSanitizerScope = false;
568 
569   /// RAII object to set/unset CodeGenFunction::IsSanitizerScope.
570   class SanitizerScope {
571     CodeGenFunction *CGF;
572   public:
573     SanitizerScope(CodeGenFunction *CGF);
574     ~SanitizerScope();
575   };
576 
577   /// In C++, whether we are code generating a thunk.  This controls whether we
578   /// should emit cleanups.
579   bool CurFuncIsThunk = false;
580 
581   /// In ARC, whether we should autorelease the return value.
582   bool AutoreleaseResult = false;
583 
584   /// Whether we processed a Microsoft-style asm block during CodeGen. These can
585   /// potentially set the return value.
586   bool SawAsmBlock = false;
587 
588   const NamedDecl *CurSEHParent = nullptr;
589 
590   /// True if the current function is an outlined SEH helper. This can be a
591   /// finally block or filter expression.
592   bool IsOutlinedSEHHelper = false;
593 
594   /// True if CodeGen currently emits code inside presereved access index
595   /// region.
596   bool IsInPreservedAIRegion = false;
597 
598   const CodeGen::CGBlockInfo *BlockInfo = nullptr;
599   llvm::Value *BlockPointer = nullptr;
600 
601   llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields;
602   FieldDecl *LambdaThisCaptureField = nullptr;
603 
604   /// A mapping from NRVO variables to the flags used to indicate
605   /// when the NRVO has been applied to this variable.
606   llvm::DenseMap<const VarDecl *, llvm::Value *> NRVOFlags;
607 
608   EHScopeStack EHStack;
609   llvm::SmallVector<char, 256> LifetimeExtendedCleanupStack;
610   llvm::SmallVector<const JumpDest *, 2> SEHTryEpilogueStack;
611 
612   llvm::Instruction *CurrentFuncletPad = nullptr;
613 
614   class CallLifetimeEnd final : public EHScopeStack::Cleanup {
615     llvm::Value *Addr;
616     llvm::Value *Size;
617 
618   public:
619     CallLifetimeEnd(Address addr, llvm::Value *size)
620         : Addr(addr.getPointer()), Size(size) {}
621 
622     void Emit(CodeGenFunction &CGF, Flags flags) override {
623       CGF.EmitLifetimeEnd(Size, Addr);
624     }
625   };
626 
627   /// Header for data within LifetimeExtendedCleanupStack.
628   struct LifetimeExtendedCleanupHeader {
629     /// The size of the following cleanup object.
630     unsigned Size;
631     /// The kind of cleanup to push: a value from the CleanupKind enumeration.
632     unsigned Kind : 31;
633     /// Whether this is a conditional cleanup.
634     unsigned IsConditional : 1;
635 
636     size_t getSize() const { return Size; }
637     CleanupKind getKind() const { return (CleanupKind)Kind; }
638     bool isConditional() const { return IsConditional; }
639   };
640 
641   /// i32s containing the indexes of the cleanup destinations.
642   Address NormalCleanupDest = Address::invalid();
643 
644   unsigned NextCleanupDestIndex = 1;
645 
646   /// FirstBlockInfo - The head of a singly-linked-list of block layouts.
647   CGBlockInfo *FirstBlockInfo = nullptr;
648 
649   /// EHResumeBlock - Unified block containing a call to llvm.eh.resume.
650   llvm::BasicBlock *EHResumeBlock = nullptr;
651 
652   /// The exception slot.  All landing pads write the current exception pointer
653   /// into this alloca.
654   llvm::Value *ExceptionSlot = nullptr;
655 
656   /// The selector slot.  Under the MandatoryCleanup model, all landing pads
657   /// write the current selector value into this alloca.
658   llvm::AllocaInst *EHSelectorSlot = nullptr;
659 
660   /// A stack of exception code slots. Entering an __except block pushes a slot
661   /// on the stack and leaving pops one. The __exception_code() intrinsic loads
662   /// a value from the top of the stack.
663   SmallVector<Address, 1> SEHCodeSlotStack;
664 
665   /// Value returned by __exception_info intrinsic.
666   llvm::Value *SEHInfo = nullptr;
667 
668   /// Emits a landing pad for the current EH stack.
669   llvm::BasicBlock *EmitLandingPad();
670 
671   llvm::BasicBlock *getInvokeDestImpl();
672 
673   template <class T>
674   typename DominatingValue<T>::saved_type saveValueInCond(T value) {
675     return DominatingValue<T>::save(*this, value);
676   }
677 
678 public:
679   /// ObjCEHValueStack - Stack of Objective-C exception values, used for
680   /// rethrows.
681   SmallVector<llvm::Value*, 8> ObjCEHValueStack;
682 
683   /// A class controlling the emission of a finally block.
684   class FinallyInfo {
685     /// Where the catchall's edge through the cleanup should go.
686     JumpDest RethrowDest;
687 
688     /// A function to call to enter the catch.
689     llvm::FunctionCallee BeginCatchFn;
690 
691     /// An i1 variable indicating whether or not the @finally is
692     /// running for an exception.
693     llvm::AllocaInst *ForEHVar;
694 
695     /// An i8* variable into which the exception pointer to rethrow
696     /// has been saved.
697     llvm::AllocaInst *SavedExnVar;
698 
699   public:
700     void enter(CodeGenFunction &CGF, const Stmt *Finally,
701                llvm::FunctionCallee beginCatchFn,
702                llvm::FunctionCallee endCatchFn, llvm::FunctionCallee rethrowFn);
703     void exit(CodeGenFunction &CGF);
704   };
705 
706   /// Returns true inside SEH __try blocks.
707   bool isSEHTryScope() const { return !SEHTryEpilogueStack.empty(); }
708 
709   /// Returns true while emitting a cleanuppad.
710   bool isCleanupPadScope() const {
711     return CurrentFuncletPad && isa<llvm::CleanupPadInst>(CurrentFuncletPad);
712   }
713 
714   /// pushFullExprCleanup - Push a cleanup to be run at the end of the
715   /// current full-expression.  Safe against the possibility that
716   /// we're currently inside a conditionally-evaluated expression.
717   template <class T, class... As>
718   void pushFullExprCleanup(CleanupKind kind, As... A) {
719     // If we're not in a conditional branch, or if none of the
720     // arguments requires saving, then use the unconditional cleanup.
721     if (!isInConditionalBranch())
722       return EHStack.pushCleanup<T>(kind, A...);
723 
724     // Stash values in a tuple so we can guarantee the order of saves.
725     typedef std::tuple<typename DominatingValue<As>::saved_type...> SavedTuple;
726     SavedTuple Saved{saveValueInCond(A)...};
727 
728     typedef EHScopeStack::ConditionalCleanup<T, As...> CleanupType;
729     EHStack.pushCleanupTuple<CleanupType>(kind, Saved);
730     initFullExprCleanup();
731   }
732 
733   /// Queue a cleanup to be pushed after finishing the current
734   /// full-expression.
735   template <class T, class... As>
736   void pushCleanupAfterFullExpr(CleanupKind Kind, As... A) {
737     if (!isInConditionalBranch())
738       return pushCleanupAfterFullExprImpl<T>(Kind, Address::invalid(), A...);
739 
740     Address ActiveFlag = createCleanupActiveFlag();
741     assert(!DominatingValue<Address>::needsSaving(ActiveFlag) &&
742            "cleanup active flag should never need saving");
743 
744     typedef std::tuple<typename DominatingValue<As>::saved_type...> SavedTuple;
745     SavedTuple Saved{saveValueInCond(A)...};
746 
747     typedef EHScopeStack::ConditionalCleanup<T, As...> CleanupType;
748     pushCleanupAfterFullExprImpl<CleanupType>(Kind, ActiveFlag, Saved);
749   }
750 
751   template <class T, class... As>
752   void pushCleanupAfterFullExprImpl(CleanupKind Kind, Address ActiveFlag,
753                                     As... A) {
754     LifetimeExtendedCleanupHeader Header = {sizeof(T), Kind,
755                                             ActiveFlag.isValid()};
756 
757     size_t OldSize = LifetimeExtendedCleanupStack.size();
758     LifetimeExtendedCleanupStack.resize(
759         LifetimeExtendedCleanupStack.size() + sizeof(Header) + Header.Size +
760         (Header.IsConditional ? sizeof(ActiveFlag) : 0));
761 
762     static_assert(sizeof(Header) % alignof(T) == 0,
763                   "Cleanup will be allocated on misaligned address");
764     char *Buffer = &LifetimeExtendedCleanupStack[OldSize];
765     new (Buffer) LifetimeExtendedCleanupHeader(Header);
766     new (Buffer + sizeof(Header)) T(A...);
767     if (Header.IsConditional)
768       new (Buffer + sizeof(Header) + sizeof(T)) Address(ActiveFlag);
769   }
770 
771   /// Set up the last cleanup that was pushed as a conditional
772   /// full-expression cleanup.
773   void initFullExprCleanup() {
774     initFullExprCleanupWithFlag(createCleanupActiveFlag());
775   }
776 
777   void initFullExprCleanupWithFlag(Address ActiveFlag);
778   Address createCleanupActiveFlag();
779 
780   /// PushDestructorCleanup - Push a cleanup to call the
781   /// complete-object destructor of an object of the given type at the
782   /// given address.  Does nothing if T is not a C++ class type with a
783   /// non-trivial destructor.
784   void PushDestructorCleanup(QualType T, Address Addr);
785 
786   /// PushDestructorCleanup - Push a cleanup to call the
787   /// complete-object variant of the given destructor on the object at
788   /// the given address.
789   void PushDestructorCleanup(const CXXDestructorDecl *Dtor, QualType T,
790                              Address Addr);
791 
792   /// PopCleanupBlock - Will pop the cleanup entry on the stack and
793   /// process all branch fixups.
794   void PopCleanupBlock(bool FallThroughIsBranchThrough = false);
795 
796   /// DeactivateCleanupBlock - Deactivates the given cleanup block.
797   /// The block cannot be reactivated.  Pops it if it's the top of the
798   /// stack.
799   ///
800   /// \param DominatingIP - An instruction which is known to
801   ///   dominate the current IP (if set) and which lies along
802   ///   all paths of execution between the current IP and the
803   ///   the point at which the cleanup comes into scope.
804   void DeactivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
805                               llvm::Instruction *DominatingIP);
806 
807   /// ActivateCleanupBlock - Activates an initially-inactive cleanup.
808   /// Cannot be used to resurrect a deactivated cleanup.
809   ///
810   /// \param DominatingIP - An instruction which is known to
811   ///   dominate the current IP (if set) and which lies along
812   ///   all paths of execution between the current IP and the
813   ///   the point at which the cleanup comes into scope.
814   void ActivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
815                             llvm::Instruction *DominatingIP);
816 
817   /// Enters a new scope for capturing cleanups, all of which
818   /// will be executed once the scope is exited.
819   class RunCleanupsScope {
820     EHScopeStack::stable_iterator CleanupStackDepth, OldCleanupScopeDepth;
821     size_t LifetimeExtendedCleanupStackSize;
822     bool OldDidCallStackSave;
823   protected:
824     bool PerformCleanup;
825   private:
826 
827     RunCleanupsScope(const RunCleanupsScope &) = delete;
828     void operator=(const RunCleanupsScope &) = delete;
829 
830   protected:
831     CodeGenFunction& CGF;
832 
833   public:
834     /// Enter a new cleanup scope.
835     explicit RunCleanupsScope(CodeGenFunction &CGF)
836       : PerformCleanup(true), CGF(CGF)
837     {
838       CleanupStackDepth = CGF.EHStack.stable_begin();
839       LifetimeExtendedCleanupStackSize =
840           CGF.LifetimeExtendedCleanupStack.size();
841       OldDidCallStackSave = CGF.DidCallStackSave;
842       CGF.DidCallStackSave = false;
843       OldCleanupScopeDepth = CGF.CurrentCleanupScopeDepth;
844       CGF.CurrentCleanupScopeDepth = CleanupStackDepth;
845     }
846 
847     /// Exit this cleanup scope, emitting any accumulated cleanups.
848     ~RunCleanupsScope() {
849       if (PerformCleanup)
850         ForceCleanup();
851     }
852 
853     /// Determine whether this scope requires any cleanups.
854     bool requiresCleanups() const {
855       return CGF.EHStack.stable_begin() != CleanupStackDepth;
856     }
857 
858     /// Force the emission of cleanups now, instead of waiting
859     /// until this object is destroyed.
860     /// \param ValuesToReload - A list of values that need to be available at
861     /// the insertion point after cleanup emission. If cleanup emission created
862     /// a shared cleanup block, these value pointers will be rewritten.
863     /// Otherwise, they not will be modified.
864     void ForceCleanup(std::initializer_list<llvm::Value**> ValuesToReload = {}) {
865       assert(PerformCleanup && "Already forced cleanup");
866       CGF.DidCallStackSave = OldDidCallStackSave;
867       CGF.PopCleanupBlocks(CleanupStackDepth, LifetimeExtendedCleanupStackSize,
868                            ValuesToReload);
869       PerformCleanup = false;
870       CGF.CurrentCleanupScopeDepth = OldCleanupScopeDepth;
871     }
872   };
873 
874   // Cleanup stack depth of the RunCleanupsScope that was pushed most recently.
875   EHScopeStack::stable_iterator CurrentCleanupScopeDepth =
876       EHScopeStack::stable_end();
877 
878   class LexicalScope : public RunCleanupsScope {
879     SourceRange Range;
880     SmallVector<const LabelDecl*, 4> Labels;
881     LexicalScope *ParentScope;
882 
883     LexicalScope(const LexicalScope &) = delete;
884     void operator=(const LexicalScope &) = delete;
885 
886   public:
887     /// Enter a new cleanup scope.
888     explicit LexicalScope(CodeGenFunction &CGF, SourceRange Range)
889       : RunCleanupsScope(CGF), Range(Range), ParentScope(CGF.CurLexicalScope) {
890       CGF.CurLexicalScope = this;
891       if (CGDebugInfo *DI = CGF.getDebugInfo())
892         DI->EmitLexicalBlockStart(CGF.Builder, Range.getBegin());
893     }
894 
895     void addLabel(const LabelDecl *label) {
896       assert(PerformCleanup && "adding label to dead scope?");
897       Labels.push_back(label);
898     }
899 
900     /// Exit this cleanup scope, emitting any accumulated
901     /// cleanups.
902     ~LexicalScope() {
903       if (CGDebugInfo *DI = CGF.getDebugInfo())
904         DI->EmitLexicalBlockEnd(CGF.Builder, Range.getEnd());
905 
906       // If we should perform a cleanup, force them now.  Note that
907       // this ends the cleanup scope before rescoping any labels.
908       if (PerformCleanup) {
909         ApplyDebugLocation DL(CGF, Range.getEnd());
910         ForceCleanup();
911       }
912     }
913 
914     /// Force the emission of cleanups now, instead of waiting
915     /// until this object is destroyed.
916     void ForceCleanup() {
917       CGF.CurLexicalScope = ParentScope;
918       RunCleanupsScope::ForceCleanup();
919 
920       if (!Labels.empty())
921         rescopeLabels();
922     }
923 
924     bool hasLabels() const {
925       return !Labels.empty();
926     }
927 
928     void rescopeLabels();
929   };
930 
931   typedef llvm::DenseMap<const Decl *, Address> DeclMapTy;
932 
933   /// The class used to assign some variables some temporarily addresses.
934   class OMPMapVars {
935     DeclMapTy SavedLocals;
936     DeclMapTy SavedTempAddresses;
937     OMPMapVars(const OMPMapVars &) = delete;
938     void operator=(const OMPMapVars &) = delete;
939 
940   public:
941     explicit OMPMapVars() = default;
942     ~OMPMapVars() {
943       assert(SavedLocals.empty() && "Did not restored original addresses.");
944     };
945 
946     /// Sets the address of the variable \p LocalVD to be \p TempAddr in
947     /// function \p CGF.
948     /// \return true if at least one variable was set already, false otherwise.
949     bool setVarAddr(CodeGenFunction &CGF, const VarDecl *LocalVD,
950                     Address TempAddr) {
951       LocalVD = LocalVD->getCanonicalDecl();
952       // Only save it once.
953       if (SavedLocals.count(LocalVD)) return false;
954 
955       // Copy the existing local entry to SavedLocals.
956       auto it = CGF.LocalDeclMap.find(LocalVD);
957       if (it != CGF.LocalDeclMap.end())
958         SavedLocals.try_emplace(LocalVD, it->second);
959       else
960         SavedLocals.try_emplace(LocalVD, Address::invalid());
961 
962       // Generate the private entry.
963       QualType VarTy = LocalVD->getType();
964       if (VarTy->isReferenceType()) {
965         Address Temp = CGF.CreateMemTemp(VarTy);
966         CGF.Builder.CreateStore(TempAddr.getPointer(), Temp);
967         TempAddr = Temp;
968       }
969       SavedTempAddresses.try_emplace(LocalVD, TempAddr);
970 
971       return true;
972     }
973 
974     /// Applies new addresses to the list of the variables.
975     /// \return true if at least one variable is using new address, false
976     /// otherwise.
977     bool apply(CodeGenFunction &CGF) {
978       copyInto(SavedTempAddresses, CGF.LocalDeclMap);
979       SavedTempAddresses.clear();
980       return !SavedLocals.empty();
981     }
982 
983     /// Restores original addresses of the variables.
984     void restore(CodeGenFunction &CGF) {
985       if (!SavedLocals.empty()) {
986         copyInto(SavedLocals, CGF.LocalDeclMap);
987         SavedLocals.clear();
988       }
989     }
990 
991   private:
992     /// Copy all the entries in the source map over the corresponding
993     /// entries in the destination, which must exist.
994     static void copyInto(const DeclMapTy &Src, DeclMapTy &Dest) {
995       for (auto &Pair : Src) {
996         if (!Pair.second.isValid()) {
997           Dest.erase(Pair.first);
998           continue;
999         }
1000 
1001         auto I = Dest.find(Pair.first);
1002         if (I != Dest.end())
1003           I->second = Pair.second;
1004         else
1005           Dest.insert(Pair);
1006       }
1007     }
1008   };
1009 
1010   /// The scope used to remap some variables as private in the OpenMP loop body
1011   /// (or other captured region emitted without outlining), and to restore old
1012   /// vars back on exit.
1013   class OMPPrivateScope : public RunCleanupsScope {
1014     OMPMapVars MappedVars;
1015     OMPPrivateScope(const OMPPrivateScope &) = delete;
1016     void operator=(const OMPPrivateScope &) = delete;
1017 
1018   public:
1019     /// Enter a new OpenMP private scope.
1020     explicit OMPPrivateScope(CodeGenFunction &CGF) : RunCleanupsScope(CGF) {}
1021 
1022     /// Registers \p LocalVD variable as a private and apply \p PrivateGen
1023     /// function for it to generate corresponding private variable. \p
1024     /// PrivateGen returns an address of the generated private variable.
1025     /// \return true if the variable is registered as private, false if it has
1026     /// been privatized already.
1027     bool addPrivate(const VarDecl *LocalVD,
1028                     const llvm::function_ref<Address()> PrivateGen) {
1029       assert(PerformCleanup && "adding private to dead scope");
1030       return MappedVars.setVarAddr(CGF, LocalVD, PrivateGen());
1031     }
1032 
1033     /// Privatizes local variables previously registered as private.
1034     /// Registration is separate from the actual privatization to allow
1035     /// initializers use values of the original variables, not the private one.
1036     /// This is important, for example, if the private variable is a class
1037     /// variable initialized by a constructor that references other private
1038     /// variables. But at initialization original variables must be used, not
1039     /// private copies.
1040     /// \return true if at least one variable was privatized, false otherwise.
1041     bool Privatize() { return MappedVars.apply(CGF); }
1042 
1043     void ForceCleanup() {
1044       RunCleanupsScope::ForceCleanup();
1045       MappedVars.restore(CGF);
1046     }
1047 
1048     /// Exit scope - all the mapped variables are restored.
1049     ~OMPPrivateScope() {
1050       if (PerformCleanup)
1051         ForceCleanup();
1052     }
1053 
1054     /// Checks if the global variable is captured in current function.
1055     bool isGlobalVarCaptured(const VarDecl *VD) const {
1056       VD = VD->getCanonicalDecl();
1057       return !VD->isLocalVarDeclOrParm() && CGF.LocalDeclMap.count(VD) > 0;
1058     }
1059   };
1060 
1061   /// Save/restore original map of previously emitted local vars in case when we
1062   /// need to duplicate emission of the same code several times in the same
1063   /// function for OpenMP code.
1064   class OMPLocalDeclMapRAII {
1065     CodeGenFunction &CGF;
1066     DeclMapTy SavedMap;
1067 
1068   public:
1069     OMPLocalDeclMapRAII(CodeGenFunction &CGF)
1070         : CGF(CGF), SavedMap(CGF.LocalDeclMap) {}
1071     ~OMPLocalDeclMapRAII() { SavedMap.swap(CGF.LocalDeclMap); }
1072   };
1073 
1074   /// Takes the old cleanup stack size and emits the cleanup blocks
1075   /// that have been added.
1076   void
1077   PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
1078                    std::initializer_list<llvm::Value **> ValuesToReload = {});
1079 
1080   /// Takes the old cleanup stack size and emits the cleanup blocks
1081   /// that have been added, then adds all lifetime-extended cleanups from
1082   /// the given position to the stack.
1083   void
1084   PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
1085                    size_t OldLifetimeExtendedStackSize,
1086                    std::initializer_list<llvm::Value **> ValuesToReload = {});
1087 
1088   void ResolveBranchFixups(llvm::BasicBlock *Target);
1089 
1090   /// The given basic block lies in the current EH scope, but may be a
1091   /// target of a potentially scope-crossing jump; get a stable handle
1092   /// to which we can perform this jump later.
1093   JumpDest getJumpDestInCurrentScope(llvm::BasicBlock *Target) {
1094     return JumpDest(Target,
1095                     EHStack.getInnermostNormalCleanup(),
1096                     NextCleanupDestIndex++);
1097   }
1098 
1099   /// The given basic block lies in the current EH scope, but may be a
1100   /// target of a potentially scope-crossing jump; get a stable handle
1101   /// to which we can perform this jump later.
1102   JumpDest getJumpDestInCurrentScope(StringRef Name = StringRef()) {
1103     return getJumpDestInCurrentScope(createBasicBlock(Name));
1104   }
1105 
1106   /// EmitBranchThroughCleanup - Emit a branch from the current insert
1107   /// block through the normal cleanup handling code (if any) and then
1108   /// on to \arg Dest.
1109   void EmitBranchThroughCleanup(JumpDest Dest);
1110 
1111   /// isObviouslyBranchWithoutCleanups - Return true if a branch to the
1112   /// specified destination obviously has no cleanups to run.  'false' is always
1113   /// a conservatively correct answer for this method.
1114   bool isObviouslyBranchWithoutCleanups(JumpDest Dest) const;
1115 
1116   /// popCatchScope - Pops the catch scope at the top of the EHScope
1117   /// stack, emitting any required code (other than the catch handlers
1118   /// themselves).
1119   void popCatchScope();
1120 
1121   llvm::BasicBlock *getEHResumeBlock(bool isCleanup);
1122   llvm::BasicBlock *getEHDispatchBlock(EHScopeStack::stable_iterator scope);
1123   llvm::BasicBlock *
1124   getFuncletEHDispatchBlock(EHScopeStack::stable_iterator scope);
1125 
1126   /// An object to manage conditionally-evaluated expressions.
1127   class ConditionalEvaluation {
1128     llvm::BasicBlock *StartBB;
1129 
1130   public:
1131     ConditionalEvaluation(CodeGenFunction &CGF)
1132       : StartBB(CGF.Builder.GetInsertBlock()) {}
1133 
1134     void begin(CodeGenFunction &CGF) {
1135       assert(CGF.OutermostConditional != this);
1136       if (!CGF.OutermostConditional)
1137         CGF.OutermostConditional = this;
1138     }
1139 
1140     void end(CodeGenFunction &CGF) {
1141       assert(CGF.OutermostConditional != nullptr);
1142       if (CGF.OutermostConditional == this)
1143         CGF.OutermostConditional = nullptr;
1144     }
1145 
1146     /// Returns a block which will be executed prior to each
1147     /// evaluation of the conditional code.
1148     llvm::BasicBlock *getStartingBlock() const {
1149       return StartBB;
1150     }
1151   };
1152 
1153   /// isInConditionalBranch - Return true if we're currently emitting
1154   /// one branch or the other of a conditional expression.
1155   bool isInConditionalBranch() const { return OutermostConditional != nullptr; }
1156 
1157   void setBeforeOutermostConditional(llvm::Value *value, Address addr) {
1158     assert(isInConditionalBranch());
1159     llvm::BasicBlock *block = OutermostConditional->getStartingBlock();
1160     auto store = new llvm::StoreInst(value, addr.getPointer(), &block->back());
1161     store->setAlignment(addr.getAlignment().getAsAlign());
1162   }
1163 
1164   /// An RAII object to record that we're evaluating a statement
1165   /// expression.
1166   class StmtExprEvaluation {
1167     CodeGenFunction &CGF;
1168 
1169     /// We have to save the outermost conditional: cleanups in a
1170     /// statement expression aren't conditional just because the
1171     /// StmtExpr is.
1172     ConditionalEvaluation *SavedOutermostConditional;
1173 
1174   public:
1175     StmtExprEvaluation(CodeGenFunction &CGF)
1176       : CGF(CGF), SavedOutermostConditional(CGF.OutermostConditional) {
1177       CGF.OutermostConditional = nullptr;
1178     }
1179 
1180     ~StmtExprEvaluation() {
1181       CGF.OutermostConditional = SavedOutermostConditional;
1182       CGF.EnsureInsertPoint();
1183     }
1184   };
1185 
1186   /// An object which temporarily prevents a value from being
1187   /// destroyed by aggressive peephole optimizations that assume that
1188   /// all uses of a value have been realized in the IR.
1189   class PeepholeProtection {
1190     llvm::Instruction *Inst;
1191     friend class CodeGenFunction;
1192 
1193   public:
1194     PeepholeProtection() : Inst(nullptr) {}
1195   };
1196 
1197   /// A non-RAII class containing all the information about a bound
1198   /// opaque value.  OpaqueValueMapping, below, is a RAII wrapper for
1199   /// this which makes individual mappings very simple; using this
1200   /// class directly is useful when you have a variable number of
1201   /// opaque values or don't want the RAII functionality for some
1202   /// reason.
1203   class OpaqueValueMappingData {
1204     const OpaqueValueExpr *OpaqueValue;
1205     bool BoundLValue;
1206     CodeGenFunction::PeepholeProtection Protection;
1207 
1208     OpaqueValueMappingData(const OpaqueValueExpr *ov,
1209                            bool boundLValue)
1210       : OpaqueValue(ov), BoundLValue(boundLValue) {}
1211   public:
1212     OpaqueValueMappingData() : OpaqueValue(nullptr) {}
1213 
1214     static bool shouldBindAsLValue(const Expr *expr) {
1215       // gl-values should be bound as l-values for obvious reasons.
1216       // Records should be bound as l-values because IR generation
1217       // always keeps them in memory.  Expressions of function type
1218       // act exactly like l-values but are formally required to be
1219       // r-values in C.
1220       return expr->isGLValue() ||
1221              expr->getType()->isFunctionType() ||
1222              hasAggregateEvaluationKind(expr->getType());
1223     }
1224 
1225     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
1226                                        const OpaqueValueExpr *ov,
1227                                        const Expr *e) {
1228       if (shouldBindAsLValue(ov))
1229         return bind(CGF, ov, CGF.EmitLValue(e));
1230       return bind(CGF, ov, CGF.EmitAnyExpr(e));
1231     }
1232 
1233     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
1234                                        const OpaqueValueExpr *ov,
1235                                        const LValue &lv) {
1236       assert(shouldBindAsLValue(ov));
1237       CGF.OpaqueLValues.insert(std::make_pair(ov, lv));
1238       return OpaqueValueMappingData(ov, true);
1239     }
1240 
1241     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
1242                                        const OpaqueValueExpr *ov,
1243                                        const RValue &rv) {
1244       assert(!shouldBindAsLValue(ov));
1245       CGF.OpaqueRValues.insert(std::make_pair(ov, rv));
1246 
1247       OpaqueValueMappingData data(ov, false);
1248 
1249       // Work around an extremely aggressive peephole optimization in
1250       // EmitScalarConversion which assumes that all other uses of a
1251       // value are extant.
1252       data.Protection = CGF.protectFromPeepholes(rv);
1253 
1254       return data;
1255     }
1256 
1257     bool isValid() const { return OpaqueValue != nullptr; }
1258     void clear() { OpaqueValue = nullptr; }
1259 
1260     void unbind(CodeGenFunction &CGF) {
1261       assert(OpaqueValue && "no data to unbind!");
1262 
1263       if (BoundLValue) {
1264         CGF.OpaqueLValues.erase(OpaqueValue);
1265       } else {
1266         CGF.OpaqueRValues.erase(OpaqueValue);
1267         CGF.unprotectFromPeepholes(Protection);
1268       }
1269     }
1270   };
1271 
1272   /// An RAII object to set (and then clear) a mapping for an OpaqueValueExpr.
1273   class OpaqueValueMapping {
1274     CodeGenFunction &CGF;
1275     OpaqueValueMappingData Data;
1276 
1277   public:
1278     static bool shouldBindAsLValue(const Expr *expr) {
1279       return OpaqueValueMappingData::shouldBindAsLValue(expr);
1280     }
1281 
1282     /// Build the opaque value mapping for the given conditional
1283     /// operator if it's the GNU ?: extension.  This is a common
1284     /// enough pattern that the convenience operator is really
1285     /// helpful.
1286     ///
1287     OpaqueValueMapping(CodeGenFunction &CGF,
1288                        const AbstractConditionalOperator *op) : CGF(CGF) {
1289       if (isa<ConditionalOperator>(op))
1290         // Leave Data empty.
1291         return;
1292 
1293       const BinaryConditionalOperator *e = cast<BinaryConditionalOperator>(op);
1294       Data = OpaqueValueMappingData::bind(CGF, e->getOpaqueValue(),
1295                                           e->getCommon());
1296     }
1297 
1298     /// Build the opaque value mapping for an OpaqueValueExpr whose source
1299     /// expression is set to the expression the OVE represents.
1300     OpaqueValueMapping(CodeGenFunction &CGF, const OpaqueValueExpr *OV)
1301         : CGF(CGF) {
1302       if (OV) {
1303         assert(OV->getSourceExpr() && "wrong form of OpaqueValueMapping used "
1304                                       "for OVE with no source expression");
1305         Data = OpaqueValueMappingData::bind(CGF, OV, OV->getSourceExpr());
1306       }
1307     }
1308 
1309     OpaqueValueMapping(CodeGenFunction &CGF,
1310                        const OpaqueValueExpr *opaqueValue,
1311                        LValue lvalue)
1312       : CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, lvalue)) {
1313     }
1314 
1315     OpaqueValueMapping(CodeGenFunction &CGF,
1316                        const OpaqueValueExpr *opaqueValue,
1317                        RValue rvalue)
1318       : CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, rvalue)) {
1319     }
1320 
1321     void pop() {
1322       Data.unbind(CGF);
1323       Data.clear();
1324     }
1325 
1326     ~OpaqueValueMapping() {
1327       if (Data.isValid()) Data.unbind(CGF);
1328     }
1329   };
1330 
1331 private:
1332   CGDebugInfo *DebugInfo;
1333   /// Used to create unique names for artificial VLA size debug info variables.
1334   unsigned VLAExprCounter = 0;
1335   bool DisableDebugInfo = false;
1336 
1337   /// DidCallStackSave - Whether llvm.stacksave has been called. Used to avoid
1338   /// calling llvm.stacksave for multiple VLAs in the same scope.
1339   bool DidCallStackSave = false;
1340 
1341   /// IndirectBranch - The first time an indirect goto is seen we create a block
1342   /// with an indirect branch.  Every time we see the address of a label taken,
1343   /// we add the label to the indirect goto.  Every subsequent indirect goto is
1344   /// codegen'd as a jump to the IndirectBranch's basic block.
1345   llvm::IndirectBrInst *IndirectBranch = nullptr;
1346 
1347   /// LocalDeclMap - This keeps track of the LLVM allocas or globals for local C
1348   /// decls.
1349   DeclMapTy LocalDeclMap;
1350 
1351   // Keep track of the cleanups for callee-destructed parameters pushed to the
1352   // cleanup stack so that they can be deactivated later.
1353   llvm::DenseMap<const ParmVarDecl *, EHScopeStack::stable_iterator>
1354       CalleeDestructedParamCleanups;
1355 
1356   /// SizeArguments - If a ParmVarDecl had the pass_object_size attribute, this
1357   /// will contain a mapping from said ParmVarDecl to its implicit "object_size"
1358   /// parameter.
1359   llvm::SmallDenseMap<const ParmVarDecl *, const ImplicitParamDecl *, 2>
1360       SizeArguments;
1361 
1362   /// Track escaped local variables with auto storage. Used during SEH
1363   /// outlining to produce a call to llvm.localescape.
1364   llvm::DenseMap<llvm::AllocaInst *, int> EscapedLocals;
1365 
1366   /// LabelMap - This keeps track of the LLVM basic block for each C label.
1367   llvm::DenseMap<const LabelDecl*, JumpDest> LabelMap;
1368 
1369   // BreakContinueStack - This keeps track of where break and continue
1370   // statements should jump to.
1371   struct BreakContinue {
1372     BreakContinue(JumpDest Break, JumpDest Continue)
1373       : BreakBlock(Break), ContinueBlock(Continue) {}
1374 
1375     JumpDest BreakBlock;
1376     JumpDest ContinueBlock;
1377   };
1378   SmallVector<BreakContinue, 8> BreakContinueStack;
1379 
1380   /// Handles cancellation exit points in OpenMP-related constructs.
1381   class OpenMPCancelExitStack {
1382     /// Tracks cancellation exit point and join point for cancel-related exit
1383     /// and normal exit.
1384     struct CancelExit {
1385       CancelExit() = default;
1386       CancelExit(OpenMPDirectiveKind Kind, JumpDest ExitBlock,
1387                  JumpDest ContBlock)
1388           : Kind(Kind), ExitBlock(ExitBlock), ContBlock(ContBlock) {}
1389       OpenMPDirectiveKind Kind = llvm::omp::OMPD_unknown;
1390       /// true if the exit block has been emitted already by the special
1391       /// emitExit() call, false if the default codegen is used.
1392       bool HasBeenEmitted = false;
1393       JumpDest ExitBlock;
1394       JumpDest ContBlock;
1395     };
1396 
1397     SmallVector<CancelExit, 8> Stack;
1398 
1399   public:
1400     OpenMPCancelExitStack() : Stack(1) {}
1401     ~OpenMPCancelExitStack() = default;
1402     /// Fetches the exit block for the current OpenMP construct.
1403     JumpDest getExitBlock() const { return Stack.back().ExitBlock; }
1404     /// Emits exit block with special codegen procedure specific for the related
1405     /// OpenMP construct + emits code for normal construct cleanup.
1406     void emitExit(CodeGenFunction &CGF, OpenMPDirectiveKind Kind,
1407                   const llvm::function_ref<void(CodeGenFunction &)> CodeGen) {
1408       if (Stack.back().Kind == Kind && getExitBlock().isValid()) {
1409         assert(CGF.getOMPCancelDestination(Kind).isValid());
1410         assert(CGF.HaveInsertPoint());
1411         assert(!Stack.back().HasBeenEmitted);
1412         auto IP = CGF.Builder.saveAndClearIP();
1413         CGF.EmitBlock(Stack.back().ExitBlock.getBlock());
1414         CodeGen(CGF);
1415         CGF.EmitBranch(Stack.back().ContBlock.getBlock());
1416         CGF.Builder.restoreIP(IP);
1417         Stack.back().HasBeenEmitted = true;
1418       }
1419       CodeGen(CGF);
1420     }
1421     /// Enter the cancel supporting \a Kind construct.
1422     /// \param Kind OpenMP directive that supports cancel constructs.
1423     /// \param HasCancel true, if the construct has inner cancel directive,
1424     /// false otherwise.
1425     void enter(CodeGenFunction &CGF, OpenMPDirectiveKind Kind, bool HasCancel) {
1426       Stack.push_back({Kind,
1427                        HasCancel ? CGF.getJumpDestInCurrentScope("cancel.exit")
1428                                  : JumpDest(),
1429                        HasCancel ? CGF.getJumpDestInCurrentScope("cancel.cont")
1430                                  : JumpDest()});
1431     }
1432     /// Emits default exit point for the cancel construct (if the special one
1433     /// has not be used) + join point for cancel/normal exits.
1434     void exit(CodeGenFunction &CGF) {
1435       if (getExitBlock().isValid()) {
1436         assert(CGF.getOMPCancelDestination(Stack.back().Kind).isValid());
1437         bool HaveIP = CGF.HaveInsertPoint();
1438         if (!Stack.back().HasBeenEmitted) {
1439           if (HaveIP)
1440             CGF.EmitBranchThroughCleanup(Stack.back().ContBlock);
1441           CGF.EmitBlock(Stack.back().ExitBlock.getBlock());
1442           CGF.EmitBranchThroughCleanup(Stack.back().ContBlock);
1443         }
1444         CGF.EmitBlock(Stack.back().ContBlock.getBlock());
1445         if (!HaveIP) {
1446           CGF.Builder.CreateUnreachable();
1447           CGF.Builder.ClearInsertionPoint();
1448         }
1449       }
1450       Stack.pop_back();
1451     }
1452   };
1453   OpenMPCancelExitStack OMPCancelStack;
1454 
1455   CodeGenPGO PGO;
1456 
1457   /// Calculate branch weights appropriate for PGO data
1458   llvm::MDNode *createProfileWeights(uint64_t TrueCount, uint64_t FalseCount);
1459   llvm::MDNode *createProfileWeights(ArrayRef<uint64_t> Weights);
1460   llvm::MDNode *createProfileWeightsForLoop(const Stmt *Cond,
1461                                             uint64_t LoopCount);
1462 
1463 public:
1464   /// Increment the profiler's counter for the given statement by \p StepV.
1465   /// If \p StepV is null, the default increment is 1.
1466   void incrementProfileCounter(const Stmt *S, llvm::Value *StepV = nullptr) {
1467     if (CGM.getCodeGenOpts().hasProfileClangInstr())
1468       PGO.emitCounterIncrement(Builder, S, StepV);
1469     PGO.setCurrentStmt(S);
1470   }
1471 
1472   /// Get the profiler's count for the given statement.
1473   uint64_t getProfileCount(const Stmt *S) {
1474     Optional<uint64_t> Count = PGO.getStmtCount(S);
1475     if (!Count.hasValue())
1476       return 0;
1477     return *Count;
1478   }
1479 
1480   /// Set the profiler's current count.
1481   void setCurrentProfileCount(uint64_t Count) {
1482     PGO.setCurrentRegionCount(Count);
1483   }
1484 
1485   /// Get the profiler's current count. This is generally the count for the most
1486   /// recently incremented counter.
1487   uint64_t getCurrentProfileCount() {
1488     return PGO.getCurrentRegionCount();
1489   }
1490 
1491 private:
1492 
1493   /// SwitchInsn - This is nearest current switch instruction. It is null if
1494   /// current context is not in a switch.
1495   llvm::SwitchInst *SwitchInsn = nullptr;
1496   /// The branch weights of SwitchInsn when doing instrumentation based PGO.
1497   SmallVector<uint64_t, 16> *SwitchWeights = nullptr;
1498 
1499   /// CaseRangeBlock - This block holds if condition check for last case
1500   /// statement range in current switch instruction.
1501   llvm::BasicBlock *CaseRangeBlock = nullptr;
1502 
1503   /// OpaqueLValues - Keeps track of the current set of opaque value
1504   /// expressions.
1505   llvm::DenseMap<const OpaqueValueExpr *, LValue> OpaqueLValues;
1506   llvm::DenseMap<const OpaqueValueExpr *, RValue> OpaqueRValues;
1507 
1508   // VLASizeMap - This keeps track of the associated size for each VLA type.
1509   // We track this by the size expression rather than the type itself because
1510   // in certain situations, like a const qualifier applied to an VLA typedef,
1511   // multiple VLA types can share the same size expression.
1512   // FIXME: Maybe this could be a stack of maps that is pushed/popped as we
1513   // enter/leave scopes.
1514   llvm::DenseMap<const Expr*, llvm::Value*> VLASizeMap;
1515 
1516   /// A block containing a single 'unreachable' instruction.  Created
1517   /// lazily by getUnreachableBlock().
1518   llvm::BasicBlock *UnreachableBlock = nullptr;
1519 
1520   /// Counts of the number return expressions in the function.
1521   unsigned NumReturnExprs = 0;
1522 
1523   /// Count the number of simple (constant) return expressions in the function.
1524   unsigned NumSimpleReturnExprs = 0;
1525 
1526   /// The last regular (non-return) debug location (breakpoint) in the function.
1527   SourceLocation LastStopPoint;
1528 
1529 public:
1530   /// Source location information about the default argument or member
1531   /// initializer expression we're evaluating, if any.
1532   CurrentSourceLocExprScope CurSourceLocExprScope;
1533   using SourceLocExprScopeGuard =
1534       CurrentSourceLocExprScope::SourceLocExprScopeGuard;
1535 
1536   /// A scope within which we are constructing the fields of an object which
1537   /// might use a CXXDefaultInitExpr. This stashes away a 'this' value to use
1538   /// if we need to evaluate a CXXDefaultInitExpr within the evaluation.
1539   class FieldConstructionScope {
1540   public:
1541     FieldConstructionScope(CodeGenFunction &CGF, Address This)
1542         : CGF(CGF), OldCXXDefaultInitExprThis(CGF.CXXDefaultInitExprThis) {
1543       CGF.CXXDefaultInitExprThis = This;
1544     }
1545     ~FieldConstructionScope() {
1546       CGF.CXXDefaultInitExprThis = OldCXXDefaultInitExprThis;
1547     }
1548 
1549   private:
1550     CodeGenFunction &CGF;
1551     Address OldCXXDefaultInitExprThis;
1552   };
1553 
1554   /// The scope of a CXXDefaultInitExpr. Within this scope, the value of 'this'
1555   /// is overridden to be the object under construction.
1556   class CXXDefaultInitExprScope  {
1557   public:
1558     CXXDefaultInitExprScope(CodeGenFunction &CGF, const CXXDefaultInitExpr *E)
1559         : CGF(CGF), OldCXXThisValue(CGF.CXXThisValue),
1560           OldCXXThisAlignment(CGF.CXXThisAlignment),
1561           SourceLocScope(E, CGF.CurSourceLocExprScope) {
1562       CGF.CXXThisValue = CGF.CXXDefaultInitExprThis.getPointer();
1563       CGF.CXXThisAlignment = CGF.CXXDefaultInitExprThis.getAlignment();
1564     }
1565     ~CXXDefaultInitExprScope() {
1566       CGF.CXXThisValue = OldCXXThisValue;
1567       CGF.CXXThisAlignment = OldCXXThisAlignment;
1568     }
1569 
1570   public:
1571     CodeGenFunction &CGF;
1572     llvm::Value *OldCXXThisValue;
1573     CharUnits OldCXXThisAlignment;
1574     SourceLocExprScopeGuard SourceLocScope;
1575   };
1576 
1577   struct CXXDefaultArgExprScope : SourceLocExprScopeGuard {
1578     CXXDefaultArgExprScope(CodeGenFunction &CGF, const CXXDefaultArgExpr *E)
1579         : SourceLocExprScopeGuard(E, CGF.CurSourceLocExprScope) {}
1580   };
1581 
1582   /// The scope of an ArrayInitLoopExpr. Within this scope, the value of the
1583   /// current loop index is overridden.
1584   class ArrayInitLoopExprScope {
1585   public:
1586     ArrayInitLoopExprScope(CodeGenFunction &CGF, llvm::Value *Index)
1587       : CGF(CGF), OldArrayInitIndex(CGF.ArrayInitIndex) {
1588       CGF.ArrayInitIndex = Index;
1589     }
1590     ~ArrayInitLoopExprScope() {
1591       CGF.ArrayInitIndex = OldArrayInitIndex;
1592     }
1593 
1594   private:
1595     CodeGenFunction &CGF;
1596     llvm::Value *OldArrayInitIndex;
1597   };
1598 
1599   class InlinedInheritingConstructorScope {
1600   public:
1601     InlinedInheritingConstructorScope(CodeGenFunction &CGF, GlobalDecl GD)
1602         : CGF(CGF), OldCurGD(CGF.CurGD), OldCurFuncDecl(CGF.CurFuncDecl),
1603           OldCurCodeDecl(CGF.CurCodeDecl),
1604           OldCXXABIThisDecl(CGF.CXXABIThisDecl),
1605           OldCXXABIThisValue(CGF.CXXABIThisValue),
1606           OldCXXThisValue(CGF.CXXThisValue),
1607           OldCXXABIThisAlignment(CGF.CXXABIThisAlignment),
1608           OldCXXThisAlignment(CGF.CXXThisAlignment),
1609           OldReturnValue(CGF.ReturnValue), OldFnRetTy(CGF.FnRetTy),
1610           OldCXXInheritedCtorInitExprArgs(
1611               std::move(CGF.CXXInheritedCtorInitExprArgs)) {
1612       CGF.CurGD = GD;
1613       CGF.CurFuncDecl = CGF.CurCodeDecl =
1614           cast<CXXConstructorDecl>(GD.getDecl());
1615       CGF.CXXABIThisDecl = nullptr;
1616       CGF.CXXABIThisValue = nullptr;
1617       CGF.CXXThisValue = nullptr;
1618       CGF.CXXABIThisAlignment = CharUnits();
1619       CGF.CXXThisAlignment = CharUnits();
1620       CGF.ReturnValue = Address::invalid();
1621       CGF.FnRetTy = QualType();
1622       CGF.CXXInheritedCtorInitExprArgs.clear();
1623     }
1624     ~InlinedInheritingConstructorScope() {
1625       CGF.CurGD = OldCurGD;
1626       CGF.CurFuncDecl = OldCurFuncDecl;
1627       CGF.CurCodeDecl = OldCurCodeDecl;
1628       CGF.CXXABIThisDecl = OldCXXABIThisDecl;
1629       CGF.CXXABIThisValue = OldCXXABIThisValue;
1630       CGF.CXXThisValue = OldCXXThisValue;
1631       CGF.CXXABIThisAlignment = OldCXXABIThisAlignment;
1632       CGF.CXXThisAlignment = OldCXXThisAlignment;
1633       CGF.ReturnValue = OldReturnValue;
1634       CGF.FnRetTy = OldFnRetTy;
1635       CGF.CXXInheritedCtorInitExprArgs =
1636           std::move(OldCXXInheritedCtorInitExprArgs);
1637     }
1638 
1639   private:
1640     CodeGenFunction &CGF;
1641     GlobalDecl OldCurGD;
1642     const Decl *OldCurFuncDecl;
1643     const Decl *OldCurCodeDecl;
1644     ImplicitParamDecl *OldCXXABIThisDecl;
1645     llvm::Value *OldCXXABIThisValue;
1646     llvm::Value *OldCXXThisValue;
1647     CharUnits OldCXXABIThisAlignment;
1648     CharUnits OldCXXThisAlignment;
1649     Address OldReturnValue;
1650     QualType OldFnRetTy;
1651     CallArgList OldCXXInheritedCtorInitExprArgs;
1652   };
1653 
1654 private:
1655   /// CXXThisDecl - When generating code for a C++ member function,
1656   /// this will hold the implicit 'this' declaration.
1657   ImplicitParamDecl *CXXABIThisDecl = nullptr;
1658   llvm::Value *CXXABIThisValue = nullptr;
1659   llvm::Value *CXXThisValue = nullptr;
1660   CharUnits CXXABIThisAlignment;
1661   CharUnits CXXThisAlignment;
1662 
1663   /// The value of 'this' to use when evaluating CXXDefaultInitExprs within
1664   /// this expression.
1665   Address CXXDefaultInitExprThis = Address::invalid();
1666 
1667   /// The current array initialization index when evaluating an
1668   /// ArrayInitIndexExpr within an ArrayInitLoopExpr.
1669   llvm::Value *ArrayInitIndex = nullptr;
1670 
1671   /// The values of function arguments to use when evaluating
1672   /// CXXInheritedCtorInitExprs within this context.
1673   CallArgList CXXInheritedCtorInitExprArgs;
1674 
1675   /// CXXStructorImplicitParamDecl - When generating code for a constructor or
1676   /// destructor, this will hold the implicit argument (e.g. VTT).
1677   ImplicitParamDecl *CXXStructorImplicitParamDecl = nullptr;
1678   llvm::Value *CXXStructorImplicitParamValue = nullptr;
1679 
1680   /// OutermostConditional - Points to the outermost active
1681   /// conditional control.  This is used so that we know if a
1682   /// temporary should be destroyed conditionally.
1683   ConditionalEvaluation *OutermostConditional = nullptr;
1684 
1685   /// The current lexical scope.
1686   LexicalScope *CurLexicalScope = nullptr;
1687 
1688   /// The current source location that should be used for exception
1689   /// handling code.
1690   SourceLocation CurEHLocation;
1691 
1692   /// BlockByrefInfos - For each __block variable, contains
1693   /// information about the layout of the variable.
1694   llvm::DenseMap<const ValueDecl *, BlockByrefInfo> BlockByrefInfos;
1695 
1696   /// Used by -fsanitize=nullability-return to determine whether the return
1697   /// value can be checked.
1698   llvm::Value *RetValNullabilityPrecondition = nullptr;
1699 
1700   /// Check if -fsanitize=nullability-return instrumentation is required for
1701   /// this function.
1702   bool requiresReturnValueNullabilityCheck() const {
1703     return RetValNullabilityPrecondition;
1704   }
1705 
1706   /// Used to store precise source locations for return statements by the
1707   /// runtime return value checks.
1708   Address ReturnLocation = Address::invalid();
1709 
1710   /// Check if the return value of this function requires sanitization.
1711   bool requiresReturnValueCheck() const;
1712 
1713   llvm::BasicBlock *TerminateLandingPad = nullptr;
1714   llvm::BasicBlock *TerminateHandler = nullptr;
1715   llvm::BasicBlock *TrapBB = nullptr;
1716 
1717   /// Terminate funclets keyed by parent funclet pad.
1718   llvm::MapVector<llvm::Value *, llvm::BasicBlock *> TerminateFunclets;
1719 
1720   /// Largest vector width used in ths function. Will be used to create a
1721   /// function attribute.
1722   unsigned LargestVectorWidth = 0;
1723 
1724   /// True if we need emit the life-time markers.
1725   const bool ShouldEmitLifetimeMarkers;
1726 
1727   /// Add OpenCL kernel arg metadata and the kernel attribute metadata to
1728   /// the function metadata.
1729   void EmitOpenCLKernelMetadata(const FunctionDecl *FD,
1730                                 llvm::Function *Fn);
1731 
1732 public:
1733   CodeGenFunction(CodeGenModule &cgm, bool suppressNewContext=false);
1734   ~CodeGenFunction();
1735 
1736   CodeGenTypes &getTypes() const { return CGM.getTypes(); }
1737   ASTContext &getContext() const { return CGM.getContext(); }
1738   CGDebugInfo *getDebugInfo() {
1739     if (DisableDebugInfo)
1740       return nullptr;
1741     return DebugInfo;
1742   }
1743   void disableDebugInfo() { DisableDebugInfo = true; }
1744   void enableDebugInfo() { DisableDebugInfo = false; }
1745 
1746   bool shouldUseFusedARCCalls() {
1747     return CGM.getCodeGenOpts().OptimizationLevel == 0;
1748   }
1749 
1750   const LangOptions &getLangOpts() const { return CGM.getLangOpts(); }
1751 
1752   /// Returns a pointer to the function's exception object and selector slot,
1753   /// which is assigned in every landing pad.
1754   Address getExceptionSlot();
1755   Address getEHSelectorSlot();
1756 
1757   /// Returns the contents of the function's exception object and selector
1758   /// slots.
1759   llvm::Value *getExceptionFromSlot();
1760   llvm::Value *getSelectorFromSlot();
1761 
1762   Address getNormalCleanupDestSlot();
1763 
1764   llvm::BasicBlock *getUnreachableBlock() {
1765     if (!UnreachableBlock) {
1766       UnreachableBlock = createBasicBlock("unreachable");
1767       new llvm::UnreachableInst(getLLVMContext(), UnreachableBlock);
1768     }
1769     return UnreachableBlock;
1770   }
1771 
1772   llvm::BasicBlock *getInvokeDest() {
1773     if (!EHStack.requiresLandingPad()) return nullptr;
1774     return getInvokeDestImpl();
1775   }
1776 
1777   bool currentFunctionUsesSEHTry() const { return CurSEHParent != nullptr; }
1778 
1779   const TargetInfo &getTarget() const { return Target; }
1780   llvm::LLVMContext &getLLVMContext() { return CGM.getLLVMContext(); }
1781   const TargetCodeGenInfo &getTargetHooks() const {
1782     return CGM.getTargetCodeGenInfo();
1783   }
1784 
1785   //===--------------------------------------------------------------------===//
1786   //                                  Cleanups
1787   //===--------------------------------------------------------------------===//
1788 
1789   typedef void Destroyer(CodeGenFunction &CGF, Address addr, QualType ty);
1790 
1791   void pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
1792                                         Address arrayEndPointer,
1793                                         QualType elementType,
1794                                         CharUnits elementAlignment,
1795                                         Destroyer *destroyer);
1796   void pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
1797                                       llvm::Value *arrayEnd,
1798                                       QualType elementType,
1799                                       CharUnits elementAlignment,
1800                                       Destroyer *destroyer);
1801 
1802   void pushDestroy(QualType::DestructionKind dtorKind,
1803                    Address addr, QualType type);
1804   void pushEHDestroy(QualType::DestructionKind dtorKind,
1805                      Address addr, QualType type);
1806   void pushDestroy(CleanupKind kind, Address addr, QualType type,
1807                    Destroyer *destroyer, bool useEHCleanupForArray);
1808   void pushLifetimeExtendedDestroy(CleanupKind kind, Address addr,
1809                                    QualType type, Destroyer *destroyer,
1810                                    bool useEHCleanupForArray);
1811   void pushCallObjectDeleteCleanup(const FunctionDecl *OperatorDelete,
1812                                    llvm::Value *CompletePtr,
1813                                    QualType ElementType);
1814   void pushStackRestore(CleanupKind kind, Address SPMem);
1815   void emitDestroy(Address addr, QualType type, Destroyer *destroyer,
1816                    bool useEHCleanupForArray);
1817   llvm::Function *generateDestroyHelper(Address addr, QualType type,
1818                                         Destroyer *destroyer,
1819                                         bool useEHCleanupForArray,
1820                                         const VarDecl *VD);
1821   void emitArrayDestroy(llvm::Value *begin, llvm::Value *end,
1822                         QualType elementType, CharUnits elementAlign,
1823                         Destroyer *destroyer,
1824                         bool checkZeroLength, bool useEHCleanup);
1825 
1826   Destroyer *getDestroyer(QualType::DestructionKind destructionKind);
1827 
1828   /// Determines whether an EH cleanup is required to destroy a type
1829   /// with the given destruction kind.
1830   bool needsEHCleanup(QualType::DestructionKind kind) {
1831     switch (kind) {
1832     case QualType::DK_none:
1833       return false;
1834     case QualType::DK_cxx_destructor:
1835     case QualType::DK_objc_weak_lifetime:
1836     case QualType::DK_nontrivial_c_struct:
1837       return getLangOpts().Exceptions;
1838     case QualType::DK_objc_strong_lifetime:
1839       return getLangOpts().Exceptions &&
1840              CGM.getCodeGenOpts().ObjCAutoRefCountExceptions;
1841     }
1842     llvm_unreachable("bad destruction kind");
1843   }
1844 
1845   CleanupKind getCleanupKind(QualType::DestructionKind kind) {
1846     return (needsEHCleanup(kind) ? NormalAndEHCleanup : NormalCleanup);
1847   }
1848 
1849   //===--------------------------------------------------------------------===//
1850   //                                  Objective-C
1851   //===--------------------------------------------------------------------===//
1852 
1853   void GenerateObjCMethod(const ObjCMethodDecl *OMD);
1854 
1855   void StartObjCMethod(const ObjCMethodDecl *MD, const ObjCContainerDecl *CD);
1856 
1857   /// GenerateObjCGetter - Synthesize an Objective-C property getter function.
1858   void GenerateObjCGetter(ObjCImplementationDecl *IMP,
1859                           const ObjCPropertyImplDecl *PID);
1860   void generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
1861                               const ObjCPropertyImplDecl *propImpl,
1862                               const ObjCMethodDecl *GetterMothodDecl,
1863                               llvm::Constant *AtomicHelperFn);
1864 
1865   void GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
1866                                   ObjCMethodDecl *MD, bool ctor);
1867 
1868   /// GenerateObjCSetter - Synthesize an Objective-C property setter function
1869   /// for the given property.
1870   void GenerateObjCSetter(ObjCImplementationDecl *IMP,
1871                           const ObjCPropertyImplDecl *PID);
1872   void generateObjCSetterBody(const ObjCImplementationDecl *classImpl,
1873                               const ObjCPropertyImplDecl *propImpl,
1874                               llvm::Constant *AtomicHelperFn);
1875 
1876   //===--------------------------------------------------------------------===//
1877   //                                  Block Bits
1878   //===--------------------------------------------------------------------===//
1879 
1880   /// Emit block literal.
1881   /// \return an LLVM value which is a pointer to a struct which contains
1882   /// information about the block, including the block invoke function, the
1883   /// captured variables, etc.
1884   llvm::Value *EmitBlockLiteral(const BlockExpr *);
1885   static void destroyBlockInfos(CGBlockInfo *info);
1886 
1887   llvm::Function *GenerateBlockFunction(GlobalDecl GD,
1888                                         const CGBlockInfo &Info,
1889                                         const DeclMapTy &ldm,
1890                                         bool IsLambdaConversionToBlock,
1891                                         bool BuildGlobalBlock);
1892 
1893   /// Check if \p T is a C++ class that has a destructor that can throw.
1894   static bool cxxDestructorCanThrow(QualType T);
1895 
1896   llvm::Constant *GenerateCopyHelperFunction(const CGBlockInfo &blockInfo);
1897   llvm::Constant *GenerateDestroyHelperFunction(const CGBlockInfo &blockInfo);
1898   llvm::Constant *GenerateObjCAtomicSetterCopyHelperFunction(
1899                                              const ObjCPropertyImplDecl *PID);
1900   llvm::Constant *GenerateObjCAtomicGetterCopyHelperFunction(
1901                                              const ObjCPropertyImplDecl *PID);
1902   llvm::Value *EmitBlockCopyAndAutorelease(llvm::Value *Block, QualType Ty);
1903 
1904   void BuildBlockRelease(llvm::Value *DeclPtr, BlockFieldFlags flags,
1905                          bool CanThrow);
1906 
1907   class AutoVarEmission;
1908 
1909   void emitByrefStructureInit(const AutoVarEmission &emission);
1910 
1911   /// Enter a cleanup to destroy a __block variable.  Note that this
1912   /// cleanup should be a no-op if the variable hasn't left the stack
1913   /// yet; if a cleanup is required for the variable itself, that needs
1914   /// to be done externally.
1915   ///
1916   /// \param Kind Cleanup kind.
1917   ///
1918   /// \param Addr When \p LoadBlockVarAddr is false, the address of the __block
1919   /// structure that will be passed to _Block_object_dispose. When
1920   /// \p LoadBlockVarAddr is true, the address of the field of the block
1921   /// structure that holds the address of the __block structure.
1922   ///
1923   /// \param Flags The flag that will be passed to _Block_object_dispose.
1924   ///
1925   /// \param LoadBlockVarAddr Indicates whether we need to emit a load from
1926   /// \p Addr to get the address of the __block structure.
1927   void enterByrefCleanup(CleanupKind Kind, Address Addr, BlockFieldFlags Flags,
1928                          bool LoadBlockVarAddr, bool CanThrow);
1929 
1930   void setBlockContextParameter(const ImplicitParamDecl *D, unsigned argNum,
1931                                 llvm::Value *ptr);
1932 
1933   Address LoadBlockStruct();
1934   Address GetAddrOfBlockDecl(const VarDecl *var);
1935 
1936   /// BuildBlockByrefAddress - Computes the location of the
1937   /// data in a variable which is declared as __block.
1938   Address emitBlockByrefAddress(Address baseAddr, const VarDecl *V,
1939                                 bool followForward = true);
1940   Address emitBlockByrefAddress(Address baseAddr,
1941                                 const BlockByrefInfo &info,
1942                                 bool followForward,
1943                                 const llvm::Twine &name);
1944 
1945   const BlockByrefInfo &getBlockByrefInfo(const VarDecl *var);
1946 
1947   QualType BuildFunctionArgList(GlobalDecl GD, FunctionArgList &Args);
1948 
1949   void GenerateCode(GlobalDecl GD, llvm::Function *Fn,
1950                     const CGFunctionInfo &FnInfo);
1951 
1952   /// Annotate the function with an attribute that disables TSan checking at
1953   /// runtime.
1954   void markAsIgnoreThreadCheckingAtRuntime(llvm::Function *Fn);
1955 
1956   /// Emit code for the start of a function.
1957   /// \param Loc       The location to be associated with the function.
1958   /// \param StartLoc  The location of the function body.
1959   void StartFunction(GlobalDecl GD,
1960                      QualType RetTy,
1961                      llvm::Function *Fn,
1962                      const CGFunctionInfo &FnInfo,
1963                      const FunctionArgList &Args,
1964                      SourceLocation Loc = SourceLocation(),
1965                      SourceLocation StartLoc = SourceLocation());
1966 
1967   static bool IsConstructorDelegationValid(const CXXConstructorDecl *Ctor);
1968 
1969   void EmitConstructorBody(FunctionArgList &Args);
1970   void EmitDestructorBody(FunctionArgList &Args);
1971   void emitImplicitAssignmentOperatorBody(FunctionArgList &Args);
1972   void EmitFunctionBody(const Stmt *Body);
1973   void EmitBlockWithFallThrough(llvm::BasicBlock *BB, const Stmt *S);
1974 
1975   void EmitForwardingCallToLambda(const CXXMethodDecl *LambdaCallOperator,
1976                                   CallArgList &CallArgs);
1977   void EmitLambdaBlockInvokeBody();
1978   void EmitLambdaDelegatingInvokeBody(const CXXMethodDecl *MD);
1979   void EmitLambdaStaticInvokeBody(const CXXMethodDecl *MD);
1980   void EmitLambdaVLACapture(const VariableArrayType *VAT, LValue LV) {
1981     EmitStoreThroughLValue(RValue::get(VLASizeMap[VAT->getSizeExpr()]), LV);
1982   }
1983   void EmitAsanPrologueOrEpilogue(bool Prologue);
1984 
1985   /// Emit the unified return block, trying to avoid its emission when
1986   /// possible.
1987   /// \return The debug location of the user written return statement if the
1988   /// return block is is avoided.
1989   llvm::DebugLoc EmitReturnBlock();
1990 
1991   /// FinishFunction - Complete IR generation of the current function. It is
1992   /// legal to call this function even if there is no current insertion point.
1993   void FinishFunction(SourceLocation EndLoc=SourceLocation());
1994 
1995   void StartThunk(llvm::Function *Fn, GlobalDecl GD,
1996                   const CGFunctionInfo &FnInfo, bool IsUnprototyped);
1997 
1998   void EmitCallAndReturnForThunk(llvm::FunctionCallee Callee,
1999                                  const ThunkInfo *Thunk, bool IsUnprototyped);
2000 
2001   void FinishThunk();
2002 
2003   /// Emit a musttail call for a thunk with a potentially adjusted this pointer.
2004   void EmitMustTailThunk(GlobalDecl GD, llvm::Value *AdjustedThisPtr,
2005                          llvm::FunctionCallee Callee);
2006 
2007   /// Generate a thunk for the given method.
2008   void generateThunk(llvm::Function *Fn, const CGFunctionInfo &FnInfo,
2009                      GlobalDecl GD, const ThunkInfo &Thunk,
2010                      bool IsUnprototyped);
2011 
2012   llvm::Function *GenerateVarArgsThunk(llvm::Function *Fn,
2013                                        const CGFunctionInfo &FnInfo,
2014                                        GlobalDecl GD, const ThunkInfo &Thunk);
2015 
2016   void EmitCtorPrologue(const CXXConstructorDecl *CD, CXXCtorType Type,
2017                         FunctionArgList &Args);
2018 
2019   void EmitInitializerForField(FieldDecl *Field, LValue LHS, Expr *Init);
2020 
2021   /// Struct with all information about dynamic [sub]class needed to set vptr.
2022   struct VPtr {
2023     BaseSubobject Base;
2024     const CXXRecordDecl *NearestVBase;
2025     CharUnits OffsetFromNearestVBase;
2026     const CXXRecordDecl *VTableClass;
2027   };
2028 
2029   /// Initialize the vtable pointer of the given subobject.
2030   void InitializeVTablePointer(const VPtr &vptr);
2031 
2032   typedef llvm::SmallVector<VPtr, 4> VPtrsVector;
2033 
2034   typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
2035   VPtrsVector getVTablePointers(const CXXRecordDecl *VTableClass);
2036 
2037   void getVTablePointers(BaseSubobject Base, const CXXRecordDecl *NearestVBase,
2038                          CharUnits OffsetFromNearestVBase,
2039                          bool BaseIsNonVirtualPrimaryBase,
2040                          const CXXRecordDecl *VTableClass,
2041                          VisitedVirtualBasesSetTy &VBases, VPtrsVector &vptrs);
2042 
2043   void InitializeVTablePointers(const CXXRecordDecl *ClassDecl);
2044 
2045   /// GetVTablePtr - Return the Value of the vtable pointer member pointed
2046   /// to by This.
2047   llvm::Value *GetVTablePtr(Address This, llvm::Type *VTableTy,
2048                             const CXXRecordDecl *VTableClass);
2049 
2050   enum CFITypeCheckKind {
2051     CFITCK_VCall,
2052     CFITCK_NVCall,
2053     CFITCK_DerivedCast,
2054     CFITCK_UnrelatedCast,
2055     CFITCK_ICall,
2056     CFITCK_NVMFCall,
2057     CFITCK_VMFCall,
2058   };
2059 
2060   /// Derived is the presumed address of an object of type T after a
2061   /// cast. If T is a polymorphic class type, emit a check that the virtual
2062   /// table for Derived belongs to a class derived from T.
2063   void EmitVTablePtrCheckForCast(QualType T, llvm::Value *Derived,
2064                                  bool MayBeNull, CFITypeCheckKind TCK,
2065                                  SourceLocation Loc);
2066 
2067   /// EmitVTablePtrCheckForCall - Virtual method MD is being called via VTable.
2068   /// If vptr CFI is enabled, emit a check that VTable is valid.
2069   void EmitVTablePtrCheckForCall(const CXXRecordDecl *RD, llvm::Value *VTable,
2070                                  CFITypeCheckKind TCK, SourceLocation Loc);
2071 
2072   /// EmitVTablePtrCheck - Emit a check that VTable is a valid virtual table for
2073   /// RD using llvm.type.test.
2074   void EmitVTablePtrCheck(const CXXRecordDecl *RD, llvm::Value *VTable,
2075                           CFITypeCheckKind TCK, SourceLocation Loc);
2076 
2077   /// If whole-program virtual table optimization is enabled, emit an assumption
2078   /// that VTable is a member of RD's type identifier. Or, if vptr CFI is
2079   /// enabled, emit a check that VTable is a member of RD's type identifier.
2080   void EmitTypeMetadataCodeForVCall(const CXXRecordDecl *RD,
2081                                     llvm::Value *VTable, SourceLocation Loc);
2082 
2083   /// Returns whether we should perform a type checked load when loading a
2084   /// virtual function for virtual calls to members of RD. This is generally
2085   /// true when both vcall CFI and whole-program-vtables are enabled.
2086   bool ShouldEmitVTableTypeCheckedLoad(const CXXRecordDecl *RD);
2087 
2088   /// Emit a type checked load from the given vtable.
2089   llvm::Value *EmitVTableTypeCheckedLoad(const CXXRecordDecl *RD, llvm::Value *VTable,
2090                                          uint64_t VTableByteOffset);
2091 
2092   /// EnterDtorCleanups - Enter the cleanups necessary to complete the
2093   /// given phase of destruction for a destructor.  The end result
2094   /// should call destructors on members and base classes in reverse
2095   /// order of their construction.
2096   void EnterDtorCleanups(const CXXDestructorDecl *Dtor, CXXDtorType Type);
2097 
2098   /// ShouldInstrumentFunction - Return true if the current function should be
2099   /// instrumented with __cyg_profile_func_* calls
2100   bool ShouldInstrumentFunction();
2101 
2102   /// ShouldXRayInstrument - Return true if the current function should be
2103   /// instrumented with XRay nop sleds.
2104   bool ShouldXRayInstrumentFunction() const;
2105 
2106   /// AlwaysEmitXRayCustomEvents - Return true if we must unconditionally emit
2107   /// XRay custom event handling calls.
2108   bool AlwaysEmitXRayCustomEvents() const;
2109 
2110   /// AlwaysEmitXRayTypedEvents - Return true if clang must unconditionally emit
2111   /// XRay typed event handling calls.
2112   bool AlwaysEmitXRayTypedEvents() const;
2113 
2114   /// Encode an address into a form suitable for use in a function prologue.
2115   llvm::Constant *EncodeAddrForUseInPrologue(llvm::Function *F,
2116                                              llvm::Constant *Addr);
2117 
2118   /// Decode an address used in a function prologue, encoded by \c
2119   /// EncodeAddrForUseInPrologue.
2120   llvm::Value *DecodeAddrUsedInPrologue(llvm::Value *F,
2121                                         llvm::Value *EncodedAddr);
2122 
2123   /// EmitFunctionProlog - Emit the target specific LLVM code to load the
2124   /// arguments for the given function. This is also responsible for naming the
2125   /// LLVM function arguments.
2126   void EmitFunctionProlog(const CGFunctionInfo &FI,
2127                           llvm::Function *Fn,
2128                           const FunctionArgList &Args);
2129 
2130   /// EmitFunctionEpilog - Emit the target specific LLVM code to return the
2131   /// given temporary.
2132   void EmitFunctionEpilog(const CGFunctionInfo &FI, bool EmitRetDbgLoc,
2133                           SourceLocation EndLoc);
2134 
2135   /// Emit a test that checks if the return value \p RV is nonnull.
2136   void EmitReturnValueCheck(llvm::Value *RV);
2137 
2138   /// EmitStartEHSpec - Emit the start of the exception spec.
2139   void EmitStartEHSpec(const Decl *D);
2140 
2141   /// EmitEndEHSpec - Emit the end of the exception spec.
2142   void EmitEndEHSpec(const Decl *D);
2143 
2144   /// getTerminateLandingPad - Return a landing pad that just calls terminate.
2145   llvm::BasicBlock *getTerminateLandingPad();
2146 
2147   /// getTerminateLandingPad - Return a cleanup funclet that just calls
2148   /// terminate.
2149   llvm::BasicBlock *getTerminateFunclet();
2150 
2151   /// getTerminateHandler - Return a handler (not a landing pad, just
2152   /// a catch handler) that just calls terminate.  This is used when
2153   /// a terminate scope encloses a try.
2154   llvm::BasicBlock *getTerminateHandler();
2155 
2156   llvm::Type *ConvertTypeForMem(QualType T);
2157   llvm::Type *ConvertType(QualType T);
2158   llvm::Type *ConvertType(const TypeDecl *T) {
2159     return ConvertType(getContext().getTypeDeclType(T));
2160   }
2161 
2162   /// LoadObjCSelf - Load the value of self. This function is only valid while
2163   /// generating code for an Objective-C method.
2164   llvm::Value *LoadObjCSelf();
2165 
2166   /// TypeOfSelfObject - Return type of object that this self represents.
2167   QualType TypeOfSelfObject();
2168 
2169   /// getEvaluationKind - Return the TypeEvaluationKind of QualType \c T.
2170   static TypeEvaluationKind getEvaluationKind(QualType T);
2171 
2172   static bool hasScalarEvaluationKind(QualType T) {
2173     return getEvaluationKind(T) == TEK_Scalar;
2174   }
2175 
2176   static bool hasAggregateEvaluationKind(QualType T) {
2177     return getEvaluationKind(T) == TEK_Aggregate;
2178   }
2179 
2180   /// createBasicBlock - Create an LLVM basic block.
2181   llvm::BasicBlock *createBasicBlock(const Twine &name = "",
2182                                      llvm::Function *parent = nullptr,
2183                                      llvm::BasicBlock *before = nullptr) {
2184     return llvm::BasicBlock::Create(getLLVMContext(), name, parent, before);
2185   }
2186 
2187   /// getBasicBlockForLabel - Return the LLVM basicblock that the specified
2188   /// label maps to.
2189   JumpDest getJumpDestForLabel(const LabelDecl *S);
2190 
2191   /// SimplifyForwardingBlocks - If the given basic block is only a branch to
2192   /// another basic block, simplify it. This assumes that no other code could
2193   /// potentially reference the basic block.
2194   void SimplifyForwardingBlocks(llvm::BasicBlock *BB);
2195 
2196   /// EmitBlock - Emit the given block \arg BB and set it as the insert point,
2197   /// adding a fall-through branch from the current insert block if
2198   /// necessary. It is legal to call this function even if there is no current
2199   /// insertion point.
2200   ///
2201   /// IsFinished - If true, indicates that the caller has finished emitting
2202   /// branches to the given block and does not expect to emit code into it. This
2203   /// means the block can be ignored if it is unreachable.
2204   void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false);
2205 
2206   /// EmitBlockAfterUses - Emit the given block somewhere hopefully
2207   /// near its uses, and leave the insertion point in it.
2208   void EmitBlockAfterUses(llvm::BasicBlock *BB);
2209 
2210   /// EmitBranch - Emit a branch to the specified basic block from the current
2211   /// insert block, taking care to avoid creation of branches from dummy
2212   /// blocks. It is legal to call this function even if there is no current
2213   /// insertion point.
2214   ///
2215   /// This function clears the current insertion point. The caller should follow
2216   /// calls to this function with calls to Emit*Block prior to generation new
2217   /// code.
2218   void EmitBranch(llvm::BasicBlock *Block);
2219 
2220   /// HaveInsertPoint - True if an insertion point is defined. If not, this
2221   /// indicates that the current code being emitted is unreachable.
2222   bool HaveInsertPoint() const {
2223     return Builder.GetInsertBlock() != nullptr;
2224   }
2225 
2226   /// EnsureInsertPoint - Ensure that an insertion point is defined so that
2227   /// emitted IR has a place to go. Note that by definition, if this function
2228   /// creates a block then that block is unreachable; callers may do better to
2229   /// detect when no insertion point is defined and simply skip IR generation.
2230   void EnsureInsertPoint() {
2231     if (!HaveInsertPoint())
2232       EmitBlock(createBasicBlock());
2233   }
2234 
2235   /// ErrorUnsupported - Print out an error that codegen doesn't support the
2236   /// specified stmt yet.
2237   void ErrorUnsupported(const Stmt *S, const char *Type);
2238 
2239   //===--------------------------------------------------------------------===//
2240   //                                  Helpers
2241   //===--------------------------------------------------------------------===//
2242 
2243   LValue MakeAddrLValue(Address Addr, QualType T,
2244                         AlignmentSource Source = AlignmentSource::Type) {
2245     return LValue::MakeAddr(Addr, T, getContext(), LValueBaseInfo(Source),
2246                             CGM.getTBAAAccessInfo(T));
2247   }
2248 
2249   LValue MakeAddrLValue(Address Addr, QualType T, LValueBaseInfo BaseInfo,
2250                         TBAAAccessInfo TBAAInfo) {
2251     return LValue::MakeAddr(Addr, T, getContext(), BaseInfo, TBAAInfo);
2252   }
2253 
2254   LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment,
2255                         AlignmentSource Source = AlignmentSource::Type) {
2256     return LValue::MakeAddr(Address(V, Alignment), T, getContext(),
2257                             LValueBaseInfo(Source), CGM.getTBAAAccessInfo(T));
2258   }
2259 
2260   LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment,
2261                         LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo) {
2262     return LValue::MakeAddr(Address(V, Alignment), T, getContext(),
2263                             BaseInfo, TBAAInfo);
2264   }
2265 
2266   LValue MakeNaturalAlignPointeeAddrLValue(llvm::Value *V, QualType T);
2267   LValue MakeNaturalAlignAddrLValue(llvm::Value *V, QualType T);
2268   CharUnits getNaturalTypeAlignment(QualType T,
2269                                     LValueBaseInfo *BaseInfo = nullptr,
2270                                     TBAAAccessInfo *TBAAInfo = nullptr,
2271                                     bool forPointeeType = false);
2272   CharUnits getNaturalPointeeTypeAlignment(QualType T,
2273                                            LValueBaseInfo *BaseInfo = nullptr,
2274                                            TBAAAccessInfo *TBAAInfo = nullptr);
2275 
2276   Address EmitLoadOfReference(LValue RefLVal,
2277                               LValueBaseInfo *PointeeBaseInfo = nullptr,
2278                               TBAAAccessInfo *PointeeTBAAInfo = nullptr);
2279   LValue EmitLoadOfReferenceLValue(LValue RefLVal);
2280   LValue EmitLoadOfReferenceLValue(Address RefAddr, QualType RefTy,
2281                                    AlignmentSource Source =
2282                                        AlignmentSource::Type) {
2283     LValue RefLVal = MakeAddrLValue(RefAddr, RefTy, LValueBaseInfo(Source),
2284                                     CGM.getTBAAAccessInfo(RefTy));
2285     return EmitLoadOfReferenceLValue(RefLVal);
2286   }
2287 
2288   Address EmitLoadOfPointer(Address Ptr, const PointerType *PtrTy,
2289                             LValueBaseInfo *BaseInfo = nullptr,
2290                             TBAAAccessInfo *TBAAInfo = nullptr);
2291   LValue EmitLoadOfPointerLValue(Address Ptr, const PointerType *PtrTy);
2292 
2293   /// CreateTempAlloca - This creates an alloca and inserts it into the entry
2294   /// block if \p ArraySize is nullptr, otherwise inserts it at the current
2295   /// insertion point of the builder. The caller is responsible for setting an
2296   /// appropriate alignment on
2297   /// the alloca.
2298   ///
2299   /// \p ArraySize is the number of array elements to be allocated if it
2300   ///    is not nullptr.
2301   ///
2302   /// LangAS::Default is the address space of pointers to local variables and
2303   /// temporaries, as exposed in the source language. In certain
2304   /// configurations, this is not the same as the alloca address space, and a
2305   /// cast is needed to lift the pointer from the alloca AS into
2306   /// LangAS::Default. This can happen when the target uses a restricted
2307   /// address space for the stack but the source language requires
2308   /// LangAS::Default to be a generic address space. The latter condition is
2309   /// common for most programming languages; OpenCL is an exception in that
2310   /// LangAS::Default is the private address space, which naturally maps
2311   /// to the stack.
2312   ///
2313   /// Because the address of a temporary is often exposed to the program in
2314   /// various ways, this function will perform the cast. The original alloca
2315   /// instruction is returned through \p Alloca if it is not nullptr.
2316   ///
2317   /// The cast is not performaed in CreateTempAllocaWithoutCast. This is
2318   /// more efficient if the caller knows that the address will not be exposed.
2319   llvm::AllocaInst *CreateTempAlloca(llvm::Type *Ty, const Twine &Name = "tmp",
2320                                      llvm::Value *ArraySize = nullptr);
2321   Address CreateTempAlloca(llvm::Type *Ty, CharUnits align,
2322                            const Twine &Name = "tmp",
2323                            llvm::Value *ArraySize = nullptr,
2324                            Address *Alloca = nullptr);
2325   Address CreateTempAllocaWithoutCast(llvm::Type *Ty, CharUnits align,
2326                                       const Twine &Name = "tmp",
2327                                       llvm::Value *ArraySize = nullptr);
2328 
2329   /// CreateDefaultAlignedTempAlloca - This creates an alloca with the
2330   /// default ABI alignment of the given LLVM type.
2331   ///
2332   /// IMPORTANT NOTE: This is *not* generally the right alignment for
2333   /// any given AST type that happens to have been lowered to the
2334   /// given IR type.  This should only ever be used for function-local,
2335   /// IR-driven manipulations like saving and restoring a value.  Do
2336   /// not hand this address off to arbitrary IRGen routines, and especially
2337   /// do not pass it as an argument to a function that might expect a
2338   /// properly ABI-aligned value.
2339   Address CreateDefaultAlignTempAlloca(llvm::Type *Ty,
2340                                        const Twine &Name = "tmp");
2341 
2342   /// InitTempAlloca - Provide an initial value for the given alloca which
2343   /// will be observable at all locations in the function.
2344   ///
2345   /// The address should be something that was returned from one of
2346   /// the CreateTempAlloca or CreateMemTemp routines, and the
2347   /// initializer must be valid in the entry block (i.e. it must
2348   /// either be a constant or an argument value).
2349   void InitTempAlloca(Address Alloca, llvm::Value *Value);
2350 
2351   /// CreateIRTemp - Create a temporary IR object of the given type, with
2352   /// appropriate alignment. This routine should only be used when an temporary
2353   /// value needs to be stored into an alloca (for example, to avoid explicit
2354   /// PHI construction), but the type is the IR type, not the type appropriate
2355   /// for storing in memory.
2356   ///
2357   /// That is, this is exactly equivalent to CreateMemTemp, but calling
2358   /// ConvertType instead of ConvertTypeForMem.
2359   Address CreateIRTemp(QualType T, const Twine &Name = "tmp");
2360 
2361   /// CreateMemTemp - Create a temporary memory object of the given type, with
2362   /// appropriate alignmen and cast it to the default address space. Returns
2363   /// the original alloca instruction by \p Alloca if it is not nullptr.
2364   Address CreateMemTemp(QualType T, const Twine &Name = "tmp",
2365                         Address *Alloca = nullptr);
2366   Address CreateMemTemp(QualType T, CharUnits Align, const Twine &Name = "tmp",
2367                         Address *Alloca = nullptr);
2368 
2369   /// CreateMemTemp - Create a temporary memory object of the given type, with
2370   /// appropriate alignmen without casting it to the default address space.
2371   Address CreateMemTempWithoutCast(QualType T, const Twine &Name = "tmp");
2372   Address CreateMemTempWithoutCast(QualType T, CharUnits Align,
2373                                    const Twine &Name = "tmp");
2374 
2375   /// CreateAggTemp - Create a temporary memory object for the given
2376   /// aggregate type.
2377   AggValueSlot CreateAggTemp(QualType T, const Twine &Name = "tmp",
2378                              Address *Alloca = nullptr) {
2379     return AggValueSlot::forAddr(CreateMemTemp(T, Name, Alloca),
2380                                  T.getQualifiers(),
2381                                  AggValueSlot::IsNotDestructed,
2382                                  AggValueSlot::DoesNotNeedGCBarriers,
2383                                  AggValueSlot::IsNotAliased,
2384                                  AggValueSlot::DoesNotOverlap);
2385   }
2386 
2387   /// Emit a cast to void* in the appropriate address space.
2388   llvm::Value *EmitCastToVoidPtr(llvm::Value *value);
2389 
2390   /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
2391   /// expression and compare the result against zero, returning an Int1Ty value.
2392   llvm::Value *EvaluateExprAsBool(const Expr *E);
2393 
2394   /// EmitIgnoredExpr - Emit an expression in a context which ignores the result.
2395   void EmitIgnoredExpr(const Expr *E);
2396 
2397   /// EmitAnyExpr - Emit code to compute the specified expression which can have
2398   /// any type.  The result is returned as an RValue struct.  If this is an
2399   /// aggregate expression, the aggloc/agglocvolatile arguments indicate where
2400   /// the result should be returned.
2401   ///
2402   /// \param ignoreResult True if the resulting value isn't used.
2403   RValue EmitAnyExpr(const Expr *E,
2404                      AggValueSlot aggSlot = AggValueSlot::ignored(),
2405                      bool ignoreResult = false);
2406 
2407   // EmitVAListRef - Emit a "reference" to a va_list; this is either the address
2408   // or the value of the expression, depending on how va_list is defined.
2409   Address EmitVAListRef(const Expr *E);
2410 
2411   /// Emit a "reference" to a __builtin_ms_va_list; this is
2412   /// always the value of the expression, because a __builtin_ms_va_list is a
2413   /// pointer to a char.
2414   Address EmitMSVAListRef(const Expr *E);
2415 
2416   /// EmitAnyExprToTemp - Similarly to EmitAnyExpr(), however, the result will
2417   /// always be accessible even if no aggregate location is provided.
2418   RValue EmitAnyExprToTemp(const Expr *E);
2419 
2420   /// EmitAnyExprToMem - Emits the code necessary to evaluate an
2421   /// arbitrary expression into the given memory location.
2422   void EmitAnyExprToMem(const Expr *E, Address Location,
2423                         Qualifiers Quals, bool IsInitializer);
2424 
2425   void EmitAnyExprToExn(const Expr *E, Address Addr);
2426 
2427   /// EmitExprAsInit - Emits the code necessary to initialize a
2428   /// location in memory with the given initializer.
2429   void EmitExprAsInit(const Expr *init, const ValueDecl *D, LValue lvalue,
2430                       bool capturedByInit);
2431 
2432   /// hasVolatileMember - returns true if aggregate type has a volatile
2433   /// member.
2434   bool hasVolatileMember(QualType T) {
2435     if (const RecordType *RT = T->getAs<RecordType>()) {
2436       const RecordDecl *RD = cast<RecordDecl>(RT->getDecl());
2437       return RD->hasVolatileMember();
2438     }
2439     return false;
2440   }
2441 
2442   /// Determine whether a return value slot may overlap some other object.
2443   AggValueSlot::Overlap_t getOverlapForReturnValue() {
2444     // FIXME: Assuming no overlap here breaks guaranteed copy elision for base
2445     // class subobjects. These cases may need to be revisited depending on the
2446     // resolution of the relevant core issue.
2447     return AggValueSlot::DoesNotOverlap;
2448   }
2449 
2450   /// Determine whether a field initialization may overlap some other object.
2451   AggValueSlot::Overlap_t getOverlapForFieldInit(const FieldDecl *FD);
2452 
2453   /// Determine whether a base class initialization may overlap some other
2454   /// object.
2455   AggValueSlot::Overlap_t getOverlapForBaseInit(const CXXRecordDecl *RD,
2456                                                 const CXXRecordDecl *BaseRD,
2457                                                 bool IsVirtual);
2458 
2459   /// Emit an aggregate assignment.
2460   void EmitAggregateAssign(LValue Dest, LValue Src, QualType EltTy) {
2461     bool IsVolatile = hasVolatileMember(EltTy);
2462     EmitAggregateCopy(Dest, Src, EltTy, AggValueSlot::MayOverlap, IsVolatile);
2463   }
2464 
2465   void EmitAggregateCopyCtor(LValue Dest, LValue Src,
2466                              AggValueSlot::Overlap_t MayOverlap) {
2467     EmitAggregateCopy(Dest, Src, Src.getType(), MayOverlap);
2468   }
2469 
2470   /// EmitAggregateCopy - Emit an aggregate copy.
2471   ///
2472   /// \param isVolatile \c true iff either the source or the destination is
2473   ///        volatile.
2474   /// \param MayOverlap Whether the tail padding of the destination might be
2475   ///        occupied by some other object. More efficient code can often be
2476   ///        generated if not.
2477   void EmitAggregateCopy(LValue Dest, LValue Src, QualType EltTy,
2478                          AggValueSlot::Overlap_t MayOverlap,
2479                          bool isVolatile = false);
2480 
2481   /// GetAddrOfLocalVar - Return the address of a local variable.
2482   Address GetAddrOfLocalVar(const VarDecl *VD) {
2483     auto it = LocalDeclMap.find(VD);
2484     assert(it != LocalDeclMap.end() &&
2485            "Invalid argument to GetAddrOfLocalVar(), no decl!");
2486     return it->second;
2487   }
2488 
2489   /// Given an opaque value expression, return its LValue mapping if it exists,
2490   /// otherwise create one.
2491   LValue getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e);
2492 
2493   /// Given an opaque value expression, return its RValue mapping if it exists,
2494   /// otherwise create one.
2495   RValue getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e);
2496 
2497   /// Get the index of the current ArrayInitLoopExpr, if any.
2498   llvm::Value *getArrayInitIndex() { return ArrayInitIndex; }
2499 
2500   /// getAccessedFieldNo - Given an encoded value and a result number, return
2501   /// the input field number being accessed.
2502   static unsigned getAccessedFieldNo(unsigned Idx, const llvm::Constant *Elts);
2503 
2504   llvm::BlockAddress *GetAddrOfLabel(const LabelDecl *L);
2505   llvm::BasicBlock *GetIndirectGotoBlock();
2506 
2507   /// Check if \p E is a C++ "this" pointer wrapped in value-preserving casts.
2508   static bool IsWrappedCXXThis(const Expr *E);
2509 
2510   /// EmitNullInitialization - Generate code to set a value of the given type to
2511   /// null, If the type contains data member pointers, they will be initialized
2512   /// to -1 in accordance with the Itanium C++ ABI.
2513   void EmitNullInitialization(Address DestPtr, QualType Ty);
2514 
2515   /// Emits a call to an LLVM variable-argument intrinsic, either
2516   /// \c llvm.va_start or \c llvm.va_end.
2517   /// \param ArgValue A reference to the \c va_list as emitted by either
2518   /// \c EmitVAListRef or \c EmitMSVAListRef.
2519   /// \param IsStart If \c true, emits a call to \c llvm.va_start; otherwise,
2520   /// calls \c llvm.va_end.
2521   llvm::Value *EmitVAStartEnd(llvm::Value *ArgValue, bool IsStart);
2522 
2523   /// Generate code to get an argument from the passed in pointer
2524   /// and update it accordingly.
2525   /// \param VE The \c VAArgExpr for which to generate code.
2526   /// \param VAListAddr Receives a reference to the \c va_list as emitted by
2527   /// either \c EmitVAListRef or \c EmitMSVAListRef.
2528   /// \returns A pointer to the argument.
2529   // FIXME: We should be able to get rid of this method and use the va_arg
2530   // instruction in LLVM instead once it works well enough.
2531   Address EmitVAArg(VAArgExpr *VE, Address &VAListAddr);
2532 
2533   /// emitArrayLength - Compute the length of an array, even if it's a
2534   /// VLA, and drill down to the base element type.
2535   llvm::Value *emitArrayLength(const ArrayType *arrayType,
2536                                QualType &baseType,
2537                                Address &addr);
2538 
2539   /// EmitVLASize - Capture all the sizes for the VLA expressions in
2540   /// the given variably-modified type and store them in the VLASizeMap.
2541   ///
2542   /// This function can be called with a null (unreachable) insert point.
2543   void EmitVariablyModifiedType(QualType Ty);
2544 
2545   struct VlaSizePair {
2546     llvm::Value *NumElts;
2547     QualType Type;
2548 
2549     VlaSizePair(llvm::Value *NE, QualType T) : NumElts(NE), Type(T) {}
2550   };
2551 
2552   /// Return the number of elements for a single dimension
2553   /// for the given array type.
2554   VlaSizePair getVLAElements1D(const VariableArrayType *vla);
2555   VlaSizePair getVLAElements1D(QualType vla);
2556 
2557   /// Returns an LLVM value that corresponds to the size,
2558   /// in non-variably-sized elements, of a variable length array type,
2559   /// plus that largest non-variably-sized element type.  Assumes that
2560   /// the type has already been emitted with EmitVariablyModifiedType.
2561   VlaSizePair getVLASize(const VariableArrayType *vla);
2562   VlaSizePair getVLASize(QualType vla);
2563 
2564   /// LoadCXXThis - Load the value of 'this'. This function is only valid while
2565   /// generating code for an C++ member function.
2566   llvm::Value *LoadCXXThis() {
2567     assert(CXXThisValue && "no 'this' value for this function");
2568     return CXXThisValue;
2569   }
2570   Address LoadCXXThisAddress();
2571 
2572   /// LoadCXXVTT - Load the VTT parameter to base constructors/destructors have
2573   /// virtual bases.
2574   // FIXME: Every place that calls LoadCXXVTT is something
2575   // that needs to be abstracted properly.
2576   llvm::Value *LoadCXXVTT() {
2577     assert(CXXStructorImplicitParamValue && "no VTT value for this function");
2578     return CXXStructorImplicitParamValue;
2579   }
2580 
2581   /// GetAddressOfBaseOfCompleteClass - Convert the given pointer to a
2582   /// complete class to the given direct base.
2583   Address
2584   GetAddressOfDirectBaseInCompleteClass(Address Value,
2585                                         const CXXRecordDecl *Derived,
2586                                         const CXXRecordDecl *Base,
2587                                         bool BaseIsVirtual);
2588 
2589   static bool ShouldNullCheckClassCastValue(const CastExpr *Cast);
2590 
2591   /// GetAddressOfBaseClass - This function will add the necessary delta to the
2592   /// load of 'this' and returns address of the base class.
2593   Address GetAddressOfBaseClass(Address Value,
2594                                 const CXXRecordDecl *Derived,
2595                                 CastExpr::path_const_iterator PathBegin,
2596                                 CastExpr::path_const_iterator PathEnd,
2597                                 bool NullCheckValue, SourceLocation Loc);
2598 
2599   Address GetAddressOfDerivedClass(Address Value,
2600                                    const CXXRecordDecl *Derived,
2601                                    CastExpr::path_const_iterator PathBegin,
2602                                    CastExpr::path_const_iterator PathEnd,
2603                                    bool NullCheckValue);
2604 
2605   /// GetVTTParameter - Return the VTT parameter that should be passed to a
2606   /// base constructor/destructor with virtual bases.
2607   /// FIXME: VTTs are Itanium ABI-specific, so the definition should move
2608   /// to ItaniumCXXABI.cpp together with all the references to VTT.
2609   llvm::Value *GetVTTParameter(GlobalDecl GD, bool ForVirtualBase,
2610                                bool Delegating);
2611 
2612   void EmitDelegateCXXConstructorCall(const CXXConstructorDecl *Ctor,
2613                                       CXXCtorType CtorType,
2614                                       const FunctionArgList &Args,
2615                                       SourceLocation Loc);
2616   // It's important not to confuse this and the previous function. Delegating
2617   // constructors are the C++0x feature. The constructor delegate optimization
2618   // is used to reduce duplication in the base and complete consturctors where
2619   // they are substantially the same.
2620   void EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor,
2621                                         const FunctionArgList &Args);
2622 
2623   /// Emit a call to an inheriting constructor (that is, one that invokes a
2624   /// constructor inherited from a base class) by inlining its definition. This
2625   /// is necessary if the ABI does not support forwarding the arguments to the
2626   /// base class constructor (because they're variadic or similar).
2627   void EmitInlinedInheritingCXXConstructorCall(const CXXConstructorDecl *Ctor,
2628                                                CXXCtorType CtorType,
2629                                                bool ForVirtualBase,
2630                                                bool Delegating,
2631                                                CallArgList &Args);
2632 
2633   /// Emit a call to a constructor inherited from a base class, passing the
2634   /// current constructor's arguments along unmodified (without even making
2635   /// a copy).
2636   void EmitInheritedCXXConstructorCall(const CXXConstructorDecl *D,
2637                                        bool ForVirtualBase, Address This,
2638                                        bool InheritedFromVBase,
2639                                        const CXXInheritedCtorInitExpr *E);
2640 
2641   void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
2642                               bool ForVirtualBase, bool Delegating,
2643                               AggValueSlot ThisAVS, const CXXConstructExpr *E);
2644 
2645   void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
2646                               bool ForVirtualBase, bool Delegating,
2647                               Address This, CallArgList &Args,
2648                               AggValueSlot::Overlap_t Overlap,
2649                               SourceLocation Loc, bool NewPointerIsChecked);
2650 
2651   /// Emit assumption load for all bases. Requires to be be called only on
2652   /// most-derived class and not under construction of the object.
2653   void EmitVTableAssumptionLoads(const CXXRecordDecl *ClassDecl, Address This);
2654 
2655   /// Emit assumption that vptr load == global vtable.
2656   void EmitVTableAssumptionLoad(const VPtr &vptr, Address This);
2657 
2658   void EmitSynthesizedCXXCopyCtorCall(const CXXConstructorDecl *D,
2659                                       Address This, Address Src,
2660                                       const CXXConstructExpr *E);
2661 
2662   void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
2663                                   const ArrayType *ArrayTy,
2664                                   Address ArrayPtr,
2665                                   const CXXConstructExpr *E,
2666                                   bool NewPointerIsChecked,
2667                                   bool ZeroInitialization = false);
2668 
2669   void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
2670                                   llvm::Value *NumElements,
2671                                   Address ArrayPtr,
2672                                   const CXXConstructExpr *E,
2673                                   bool NewPointerIsChecked,
2674                                   bool ZeroInitialization = false);
2675 
2676   static Destroyer destroyCXXObject;
2677 
2678   void EmitCXXDestructorCall(const CXXDestructorDecl *D, CXXDtorType Type,
2679                              bool ForVirtualBase, bool Delegating, Address This,
2680                              QualType ThisTy);
2681 
2682   void EmitNewArrayInitializer(const CXXNewExpr *E, QualType elementType,
2683                                llvm::Type *ElementTy, Address NewPtr,
2684                                llvm::Value *NumElements,
2685                                llvm::Value *AllocSizeWithoutCookie);
2686 
2687   void EmitCXXTemporary(const CXXTemporary *Temporary, QualType TempType,
2688                         Address Ptr);
2689 
2690   llvm::Value *EmitLifetimeStart(uint64_t Size, llvm::Value *Addr);
2691   void EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr);
2692 
2693   llvm::Value *EmitCXXNewExpr(const CXXNewExpr *E);
2694   void EmitCXXDeleteExpr(const CXXDeleteExpr *E);
2695 
2696   void EmitDeleteCall(const FunctionDecl *DeleteFD, llvm::Value *Ptr,
2697                       QualType DeleteTy, llvm::Value *NumElements = nullptr,
2698                       CharUnits CookieSize = CharUnits());
2699 
2700   RValue EmitBuiltinNewDeleteCall(const FunctionProtoType *Type,
2701                                   const CallExpr *TheCallExpr, bool IsDelete);
2702 
2703   llvm::Value *EmitCXXTypeidExpr(const CXXTypeidExpr *E);
2704   llvm::Value *EmitDynamicCast(Address V, const CXXDynamicCastExpr *DCE);
2705   Address EmitCXXUuidofExpr(const CXXUuidofExpr *E);
2706 
2707   /// Situations in which we might emit a check for the suitability of a
2708   /// pointer or glvalue. Needs to be kept in sync with ubsan_handlers.cpp in
2709   /// compiler-rt.
2710   enum TypeCheckKind {
2711     /// Checking the operand of a load. Must be suitably sized and aligned.
2712     TCK_Load,
2713     /// Checking the destination of a store. Must be suitably sized and aligned.
2714     TCK_Store,
2715     /// Checking the bound value in a reference binding. Must be suitably sized
2716     /// and aligned, but is not required to refer to an object (until the
2717     /// reference is used), per core issue 453.
2718     TCK_ReferenceBinding,
2719     /// Checking the object expression in a non-static data member access. Must
2720     /// be an object within its lifetime.
2721     TCK_MemberAccess,
2722     /// Checking the 'this' pointer for a call to a non-static member function.
2723     /// Must be an object within its lifetime.
2724     TCK_MemberCall,
2725     /// Checking the 'this' pointer for a constructor call.
2726     TCK_ConstructorCall,
2727     /// Checking the operand of a static_cast to a derived pointer type. Must be
2728     /// null or an object within its lifetime.
2729     TCK_DowncastPointer,
2730     /// Checking the operand of a static_cast to a derived reference type. Must
2731     /// be an object within its lifetime.
2732     TCK_DowncastReference,
2733     /// Checking the operand of a cast to a base object. Must be suitably sized
2734     /// and aligned.
2735     TCK_Upcast,
2736     /// Checking the operand of a cast to a virtual base object. Must be an
2737     /// object within its lifetime.
2738     TCK_UpcastToVirtualBase,
2739     /// Checking the value assigned to a _Nonnull pointer. Must not be null.
2740     TCK_NonnullAssign,
2741     /// Checking the operand of a dynamic_cast or a typeid expression.  Must be
2742     /// null or an object within its lifetime.
2743     TCK_DynamicOperation
2744   };
2745 
2746   /// Determine whether the pointer type check \p TCK permits null pointers.
2747   static bool isNullPointerAllowed(TypeCheckKind TCK);
2748 
2749   /// Determine whether the pointer type check \p TCK requires a vptr check.
2750   static bool isVptrCheckRequired(TypeCheckKind TCK, QualType Ty);
2751 
2752   /// Whether any type-checking sanitizers are enabled. If \c false,
2753   /// calls to EmitTypeCheck can be skipped.
2754   bool sanitizePerformTypeCheck() const;
2755 
2756   /// Emit a check that \p V is the address of storage of the
2757   /// appropriate size and alignment for an object of type \p Type
2758   /// (or if ArraySize is provided, for an array of that bound).
2759   void EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, llvm::Value *V,
2760                      QualType Type, CharUnits Alignment = CharUnits::Zero(),
2761                      SanitizerSet SkippedChecks = SanitizerSet(),
2762                      llvm::Value *ArraySize = nullptr);
2763 
2764   /// Emit a check that \p Base points into an array object, which
2765   /// we can access at index \p Index. \p Accessed should be \c false if we
2766   /// this expression is used as an lvalue, for instance in "&Arr[Idx]".
2767   void EmitBoundsCheck(const Expr *E, const Expr *Base, llvm::Value *Index,
2768                        QualType IndexType, bool Accessed);
2769 
2770   llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
2771                                        bool isInc, bool isPre);
2772   ComplexPairTy EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
2773                                          bool isInc, bool isPre);
2774 
2775   /// Converts Location to a DebugLoc, if debug information is enabled.
2776   llvm::DebugLoc SourceLocToDebugLoc(SourceLocation Location);
2777 
2778   /// Get the record field index as represented in debug info.
2779   unsigned getDebugInfoFIndex(const RecordDecl *Rec, unsigned FieldIndex);
2780 
2781 
2782   //===--------------------------------------------------------------------===//
2783   //                            Declaration Emission
2784   //===--------------------------------------------------------------------===//
2785 
2786   /// EmitDecl - Emit a declaration.
2787   ///
2788   /// This function can be called with a null (unreachable) insert point.
2789   void EmitDecl(const Decl &D);
2790 
2791   /// EmitVarDecl - Emit a local variable declaration.
2792   ///
2793   /// This function can be called with a null (unreachable) insert point.
2794   void EmitVarDecl(const VarDecl &D);
2795 
2796   void EmitScalarInit(const Expr *init, const ValueDecl *D, LValue lvalue,
2797                       bool capturedByInit);
2798 
2799   typedef void SpecialInitFn(CodeGenFunction &Init, const VarDecl &D,
2800                              llvm::Value *Address);
2801 
2802   /// Determine whether the given initializer is trivial in the sense
2803   /// that it requires no code to be generated.
2804   bool isTrivialInitializer(const Expr *Init);
2805 
2806   /// EmitAutoVarDecl - Emit an auto variable declaration.
2807   ///
2808   /// This function can be called with a null (unreachable) insert point.
2809   void EmitAutoVarDecl(const VarDecl &D);
2810 
2811   class AutoVarEmission {
2812     friend class CodeGenFunction;
2813 
2814     const VarDecl *Variable;
2815 
2816     /// The address of the alloca for languages with explicit address space
2817     /// (e.g. OpenCL) or alloca casted to generic pointer for address space
2818     /// agnostic languages (e.g. C++). Invalid if the variable was emitted
2819     /// as a global constant.
2820     Address Addr;
2821 
2822     llvm::Value *NRVOFlag;
2823 
2824     /// True if the variable is a __block variable that is captured by an
2825     /// escaping block.
2826     bool IsEscapingByRef;
2827 
2828     /// True if the variable is of aggregate type and has a constant
2829     /// initializer.
2830     bool IsConstantAggregate;
2831 
2832     /// Non-null if we should use lifetime annotations.
2833     llvm::Value *SizeForLifetimeMarkers;
2834 
2835     /// Address with original alloca instruction. Invalid if the variable was
2836     /// emitted as a global constant.
2837     Address AllocaAddr;
2838 
2839     struct Invalid {};
2840     AutoVarEmission(Invalid)
2841         : Variable(nullptr), Addr(Address::invalid()),
2842           AllocaAddr(Address::invalid()) {}
2843 
2844     AutoVarEmission(const VarDecl &variable)
2845         : Variable(&variable), Addr(Address::invalid()), NRVOFlag(nullptr),
2846           IsEscapingByRef(false), IsConstantAggregate(false),
2847           SizeForLifetimeMarkers(nullptr), AllocaAddr(Address::invalid()) {}
2848 
2849     bool wasEmittedAsGlobal() const { return !Addr.isValid(); }
2850 
2851   public:
2852     static AutoVarEmission invalid() { return AutoVarEmission(Invalid()); }
2853 
2854     bool useLifetimeMarkers() const {
2855       return SizeForLifetimeMarkers != nullptr;
2856     }
2857     llvm::Value *getSizeForLifetimeMarkers() const {
2858       assert(useLifetimeMarkers());
2859       return SizeForLifetimeMarkers;
2860     }
2861 
2862     /// Returns the raw, allocated address, which is not necessarily
2863     /// the address of the object itself. It is casted to default
2864     /// address space for address space agnostic languages.
2865     Address getAllocatedAddress() const {
2866       return Addr;
2867     }
2868 
2869     /// Returns the address for the original alloca instruction.
2870     Address getOriginalAllocatedAddress() const { return AllocaAddr; }
2871 
2872     /// Returns the address of the object within this declaration.
2873     /// Note that this does not chase the forwarding pointer for
2874     /// __block decls.
2875     Address getObjectAddress(CodeGenFunction &CGF) const {
2876       if (!IsEscapingByRef) return Addr;
2877 
2878       return CGF.emitBlockByrefAddress(Addr, Variable, /*forward*/ false);
2879     }
2880   };
2881   AutoVarEmission EmitAutoVarAlloca(const VarDecl &var);
2882   void EmitAutoVarInit(const AutoVarEmission &emission);
2883   void EmitAutoVarCleanups(const AutoVarEmission &emission);
2884   void emitAutoVarTypeCleanup(const AutoVarEmission &emission,
2885                               QualType::DestructionKind dtorKind);
2886 
2887   /// Emits the alloca and debug information for the size expressions for each
2888   /// dimension of an array. It registers the association of its (1-dimensional)
2889   /// QualTypes and size expression's debug node, so that CGDebugInfo can
2890   /// reference this node when creating the DISubrange object to describe the
2891   /// array types.
2892   void EmitAndRegisterVariableArrayDimensions(CGDebugInfo *DI,
2893                                               const VarDecl &D,
2894                                               bool EmitDebugInfo);
2895 
2896   void EmitStaticVarDecl(const VarDecl &D,
2897                          llvm::GlobalValue::LinkageTypes Linkage);
2898 
2899   class ParamValue {
2900     llvm::Value *Value;
2901     unsigned Alignment;
2902     ParamValue(llvm::Value *V, unsigned A) : Value(V), Alignment(A) {}
2903   public:
2904     static ParamValue forDirect(llvm::Value *value) {
2905       return ParamValue(value, 0);
2906     }
2907     static ParamValue forIndirect(Address addr) {
2908       assert(!addr.getAlignment().isZero());
2909       return ParamValue(addr.getPointer(), addr.getAlignment().getQuantity());
2910     }
2911 
2912     bool isIndirect() const { return Alignment != 0; }
2913     llvm::Value *getAnyValue() const { return Value; }
2914 
2915     llvm::Value *getDirectValue() const {
2916       assert(!isIndirect());
2917       return Value;
2918     }
2919 
2920     Address getIndirectAddress() const {
2921       assert(isIndirect());
2922       return Address(Value, CharUnits::fromQuantity(Alignment));
2923     }
2924   };
2925 
2926   /// EmitParmDecl - Emit a ParmVarDecl or an ImplicitParamDecl.
2927   void EmitParmDecl(const VarDecl &D, ParamValue Arg, unsigned ArgNo);
2928 
2929   /// protectFromPeepholes - Protect a value that we're intending to
2930   /// store to the side, but which will probably be used later, from
2931   /// aggressive peepholing optimizations that might delete it.
2932   ///
2933   /// Pass the result to unprotectFromPeepholes to declare that
2934   /// protection is no longer required.
2935   ///
2936   /// There's no particular reason why this shouldn't apply to
2937   /// l-values, it's just that no existing peepholes work on pointers.
2938   PeepholeProtection protectFromPeepholes(RValue rvalue);
2939   void unprotectFromPeepholes(PeepholeProtection protection);
2940 
2941   void emitAlignmentAssumptionCheck(llvm::Value *Ptr, QualType Ty,
2942                                     SourceLocation Loc,
2943                                     SourceLocation AssumptionLoc,
2944                                     llvm::Value *Alignment,
2945                                     llvm::Value *OffsetValue,
2946                                     llvm::Value *TheCheck,
2947                                     llvm::Instruction *Assumption);
2948 
2949   void emitAlignmentAssumption(llvm::Value *PtrValue, QualType Ty,
2950                                SourceLocation Loc, SourceLocation AssumptionLoc,
2951                                llvm::Value *Alignment,
2952                                llvm::Value *OffsetValue = nullptr);
2953 
2954   void emitAlignmentAssumption(llvm::Value *PtrValue, const Expr *E,
2955                                SourceLocation AssumptionLoc,
2956                                llvm::Value *Alignment,
2957                                llvm::Value *OffsetValue = nullptr);
2958 
2959   //===--------------------------------------------------------------------===//
2960   //                             Statement Emission
2961   //===--------------------------------------------------------------------===//
2962 
2963   /// EmitStopPoint - Emit a debug stoppoint if we are emitting debug info.
2964   void EmitStopPoint(const Stmt *S);
2965 
2966   /// EmitStmt - Emit the code for the statement \arg S. It is legal to call
2967   /// this function even if there is no current insertion point.
2968   ///
2969   /// This function may clear the current insertion point; callers should use
2970   /// EnsureInsertPoint if they wish to subsequently generate code without first
2971   /// calling EmitBlock, EmitBranch, or EmitStmt.
2972   void EmitStmt(const Stmt *S, ArrayRef<const Attr *> Attrs = None);
2973 
2974   /// EmitSimpleStmt - Try to emit a "simple" statement which does not
2975   /// necessarily require an insertion point or debug information; typically
2976   /// because the statement amounts to a jump or a container of other
2977   /// statements.
2978   ///
2979   /// \return True if the statement was handled.
2980   bool EmitSimpleStmt(const Stmt *S);
2981 
2982   Address EmitCompoundStmt(const CompoundStmt &S, bool GetLast = false,
2983                            AggValueSlot AVS = AggValueSlot::ignored());
2984   Address EmitCompoundStmtWithoutScope(const CompoundStmt &S,
2985                                        bool GetLast = false,
2986                                        AggValueSlot AVS =
2987                                                 AggValueSlot::ignored());
2988 
2989   /// EmitLabel - Emit the block for the given label. It is legal to call this
2990   /// function even if there is no current insertion point.
2991   void EmitLabel(const LabelDecl *D); // helper for EmitLabelStmt.
2992 
2993   void EmitLabelStmt(const LabelStmt &S);
2994   void EmitAttributedStmt(const AttributedStmt &S);
2995   void EmitGotoStmt(const GotoStmt &S);
2996   void EmitIndirectGotoStmt(const IndirectGotoStmt &S);
2997   void EmitIfStmt(const IfStmt &S);
2998 
2999   void EmitWhileStmt(const WhileStmt &S,
3000                      ArrayRef<const Attr *> Attrs = None);
3001   void EmitDoStmt(const DoStmt &S, ArrayRef<const Attr *> Attrs = None);
3002   void EmitForStmt(const ForStmt &S,
3003                    ArrayRef<const Attr *> Attrs = None);
3004   void EmitReturnStmt(const ReturnStmt &S);
3005   void EmitDeclStmt(const DeclStmt &S);
3006   void EmitBreakStmt(const BreakStmt &S);
3007   void EmitContinueStmt(const ContinueStmt &S);
3008   void EmitSwitchStmt(const SwitchStmt &S);
3009   void EmitDefaultStmt(const DefaultStmt &S);
3010   void EmitCaseStmt(const CaseStmt &S);
3011   void EmitCaseStmtRange(const CaseStmt &S);
3012   void EmitAsmStmt(const AsmStmt &S);
3013 
3014   void EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S);
3015   void EmitObjCAtTryStmt(const ObjCAtTryStmt &S);
3016   void EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S);
3017   void EmitObjCAtSynchronizedStmt(const ObjCAtSynchronizedStmt &S);
3018   void EmitObjCAutoreleasePoolStmt(const ObjCAutoreleasePoolStmt &S);
3019 
3020   void EmitCoroutineBody(const CoroutineBodyStmt &S);
3021   void EmitCoreturnStmt(const CoreturnStmt &S);
3022   RValue EmitCoawaitExpr(const CoawaitExpr &E,
3023                          AggValueSlot aggSlot = AggValueSlot::ignored(),
3024                          bool ignoreResult = false);
3025   LValue EmitCoawaitLValue(const CoawaitExpr *E);
3026   RValue EmitCoyieldExpr(const CoyieldExpr &E,
3027                          AggValueSlot aggSlot = AggValueSlot::ignored(),
3028                          bool ignoreResult = false);
3029   LValue EmitCoyieldLValue(const CoyieldExpr *E);
3030   RValue EmitCoroutineIntrinsic(const CallExpr *E, unsigned int IID);
3031 
3032   void EnterCXXTryStmt(const CXXTryStmt &S, bool IsFnTryBlock = false);
3033   void ExitCXXTryStmt(const CXXTryStmt &S, bool IsFnTryBlock = false);
3034 
3035   void EmitCXXTryStmt(const CXXTryStmt &S);
3036   void EmitSEHTryStmt(const SEHTryStmt &S);
3037   void EmitSEHLeaveStmt(const SEHLeaveStmt &S);
3038   void EnterSEHTryStmt(const SEHTryStmt &S);
3039   void ExitSEHTryStmt(const SEHTryStmt &S);
3040 
3041   void pushSEHCleanup(CleanupKind kind,
3042                       llvm::Function *FinallyFunc);
3043   void startOutlinedSEHHelper(CodeGenFunction &ParentCGF, bool IsFilter,
3044                               const Stmt *OutlinedStmt);
3045 
3046   llvm::Function *GenerateSEHFilterFunction(CodeGenFunction &ParentCGF,
3047                                             const SEHExceptStmt &Except);
3048 
3049   llvm::Function *GenerateSEHFinallyFunction(CodeGenFunction &ParentCGF,
3050                                              const SEHFinallyStmt &Finally);
3051 
3052   void EmitSEHExceptionCodeSave(CodeGenFunction &ParentCGF,
3053                                 llvm::Value *ParentFP,
3054                                 llvm::Value *EntryEBP);
3055   llvm::Value *EmitSEHExceptionCode();
3056   llvm::Value *EmitSEHExceptionInfo();
3057   llvm::Value *EmitSEHAbnormalTermination();
3058 
3059   /// Emit simple code for OpenMP directives in Simd-only mode.
3060   void EmitSimpleOMPExecutableDirective(const OMPExecutableDirective &D);
3061 
3062   /// Scan the outlined statement for captures from the parent function. For
3063   /// each capture, mark the capture as escaped and emit a call to
3064   /// llvm.localrecover. Insert the localrecover result into the LocalDeclMap.
3065   void EmitCapturedLocals(CodeGenFunction &ParentCGF, const Stmt *OutlinedStmt,
3066                           bool IsFilter);
3067 
3068   /// Recovers the address of a local in a parent function. ParentVar is the
3069   /// address of the variable used in the immediate parent function. It can
3070   /// either be an alloca or a call to llvm.localrecover if there are nested
3071   /// outlined functions. ParentFP is the frame pointer of the outermost parent
3072   /// frame.
3073   Address recoverAddrOfEscapedLocal(CodeGenFunction &ParentCGF,
3074                                     Address ParentVar,
3075                                     llvm::Value *ParentFP);
3076 
3077   void EmitCXXForRangeStmt(const CXXForRangeStmt &S,
3078                            ArrayRef<const Attr *> Attrs = None);
3079 
3080   /// Controls insertion of cancellation exit blocks in worksharing constructs.
3081   class OMPCancelStackRAII {
3082     CodeGenFunction &CGF;
3083 
3084   public:
3085     OMPCancelStackRAII(CodeGenFunction &CGF, OpenMPDirectiveKind Kind,
3086                        bool HasCancel)
3087         : CGF(CGF) {
3088       CGF.OMPCancelStack.enter(CGF, Kind, HasCancel);
3089     }
3090     ~OMPCancelStackRAII() { CGF.OMPCancelStack.exit(CGF); }
3091   };
3092 
3093   /// Returns calculated size of the specified type.
3094   llvm::Value *getTypeSize(QualType Ty);
3095   LValue InitCapturedStruct(const CapturedStmt &S);
3096   llvm::Function *EmitCapturedStmt(const CapturedStmt &S, CapturedRegionKind K);
3097   llvm::Function *GenerateCapturedStmtFunction(const CapturedStmt &S);
3098   Address GenerateCapturedStmtArgument(const CapturedStmt &S);
3099   llvm::Function *GenerateOpenMPCapturedStmtFunction(const CapturedStmt &S,
3100                                                      SourceLocation Loc);
3101   void GenerateOpenMPCapturedVars(const CapturedStmt &S,
3102                                   SmallVectorImpl<llvm::Value *> &CapturedVars);
3103   void emitOMPSimpleStore(LValue LVal, RValue RVal, QualType RValTy,
3104                           SourceLocation Loc);
3105   /// Perform element by element copying of arrays with type \a
3106   /// OriginalType from \a SrcAddr to \a DestAddr using copying procedure
3107   /// generated by \a CopyGen.
3108   ///
3109   /// \param DestAddr Address of the destination array.
3110   /// \param SrcAddr Address of the source array.
3111   /// \param OriginalType Type of destination and source arrays.
3112   /// \param CopyGen Copying procedure that copies value of single array element
3113   /// to another single array element.
3114   void EmitOMPAggregateAssign(
3115       Address DestAddr, Address SrcAddr, QualType OriginalType,
3116       const llvm::function_ref<void(Address, Address)> CopyGen);
3117   /// Emit proper copying of data from one variable to another.
3118   ///
3119   /// \param OriginalType Original type of the copied variables.
3120   /// \param DestAddr Destination address.
3121   /// \param SrcAddr Source address.
3122   /// \param DestVD Destination variable used in \a CopyExpr (for arrays, has
3123   /// type of the base array element).
3124   /// \param SrcVD Source variable used in \a CopyExpr (for arrays, has type of
3125   /// the base array element).
3126   /// \param Copy Actual copygin expression for copying data from \a SrcVD to \a
3127   /// DestVD.
3128   void EmitOMPCopy(QualType OriginalType,
3129                    Address DestAddr, Address SrcAddr,
3130                    const VarDecl *DestVD, const VarDecl *SrcVD,
3131                    const Expr *Copy);
3132   /// Emit atomic update code for constructs: \a X = \a X \a BO \a E or
3133   /// \a X = \a E \a BO \a E.
3134   ///
3135   /// \param X Value to be updated.
3136   /// \param E Update value.
3137   /// \param BO Binary operation for update operation.
3138   /// \param IsXLHSInRHSPart true if \a X is LHS in RHS part of the update
3139   /// expression, false otherwise.
3140   /// \param AO Atomic ordering of the generated atomic instructions.
3141   /// \param CommonGen Code generator for complex expressions that cannot be
3142   /// expressed through atomicrmw instruction.
3143   /// \returns <true, OldAtomicValue> if simple 'atomicrmw' instruction was
3144   /// generated, <false, RValue::get(nullptr)> otherwise.
3145   std::pair<bool, RValue> EmitOMPAtomicSimpleUpdateExpr(
3146       LValue X, RValue E, BinaryOperatorKind BO, bool IsXLHSInRHSPart,
3147       llvm::AtomicOrdering AO, SourceLocation Loc,
3148       const llvm::function_ref<RValue(RValue)> CommonGen);
3149   bool EmitOMPFirstprivateClause(const OMPExecutableDirective &D,
3150                                  OMPPrivateScope &PrivateScope);
3151   void EmitOMPPrivateClause(const OMPExecutableDirective &D,
3152                             OMPPrivateScope &PrivateScope);
3153   void EmitOMPUseDevicePtrClause(
3154       const OMPClause &C, OMPPrivateScope &PrivateScope,
3155       const llvm::DenseMap<const ValueDecl *, Address> &CaptureDeviceAddrMap);
3156   /// Emit code for copyin clause in \a D directive. The next code is
3157   /// generated at the start of outlined functions for directives:
3158   /// \code
3159   /// threadprivate_var1 = master_threadprivate_var1;
3160   /// operator=(threadprivate_var2, master_threadprivate_var2);
3161   /// ...
3162   /// __kmpc_barrier(&loc, global_tid);
3163   /// \endcode
3164   ///
3165   /// \param D OpenMP directive possibly with 'copyin' clause(s).
3166   /// \returns true if at least one copyin variable is found, false otherwise.
3167   bool EmitOMPCopyinClause(const OMPExecutableDirective &D);
3168   /// Emit initial code for lastprivate variables. If some variable is
3169   /// not also firstprivate, then the default initialization is used. Otherwise
3170   /// initialization of this variable is performed by EmitOMPFirstprivateClause
3171   /// method.
3172   ///
3173   /// \param D Directive that may have 'lastprivate' directives.
3174   /// \param PrivateScope Private scope for capturing lastprivate variables for
3175   /// proper codegen in internal captured statement.
3176   ///
3177   /// \returns true if there is at least one lastprivate variable, false
3178   /// otherwise.
3179   bool EmitOMPLastprivateClauseInit(const OMPExecutableDirective &D,
3180                                     OMPPrivateScope &PrivateScope);
3181   /// Emit final copying of lastprivate values to original variables at
3182   /// the end of the worksharing or simd directive.
3183   ///
3184   /// \param D Directive that has at least one 'lastprivate' directives.
3185   /// \param IsLastIterCond Boolean condition that must be set to 'i1 true' if
3186   /// it is the last iteration of the loop code in associated directive, or to
3187   /// 'i1 false' otherwise. If this item is nullptr, no final check is required.
3188   void EmitOMPLastprivateClauseFinal(const OMPExecutableDirective &D,
3189                                      bool NoFinals,
3190                                      llvm::Value *IsLastIterCond = nullptr);
3191   /// Emit initial code for linear clauses.
3192   void EmitOMPLinearClause(const OMPLoopDirective &D,
3193                            CodeGenFunction::OMPPrivateScope &PrivateScope);
3194   /// Emit final code for linear clauses.
3195   /// \param CondGen Optional conditional code for final part of codegen for
3196   /// linear clause.
3197   void EmitOMPLinearClauseFinal(
3198       const OMPLoopDirective &D,
3199       const llvm::function_ref<llvm::Value *(CodeGenFunction &)> CondGen);
3200   /// Emit initial code for reduction variables. Creates reduction copies
3201   /// and initializes them with the values according to OpenMP standard.
3202   ///
3203   /// \param D Directive (possibly) with the 'reduction' clause.
3204   /// \param PrivateScope Private scope for capturing reduction variables for
3205   /// proper codegen in internal captured statement.
3206   ///
3207   void EmitOMPReductionClauseInit(const OMPExecutableDirective &D,
3208                                   OMPPrivateScope &PrivateScope);
3209   /// Emit final update of reduction values to original variables at
3210   /// the end of the directive.
3211   ///
3212   /// \param D Directive that has at least one 'reduction' directives.
3213   /// \param ReductionKind The kind of reduction to perform.
3214   void EmitOMPReductionClauseFinal(const OMPExecutableDirective &D,
3215                                    const OpenMPDirectiveKind ReductionKind);
3216   /// Emit initial code for linear variables. Creates private copies
3217   /// and initializes them with the values according to OpenMP standard.
3218   ///
3219   /// \param D Directive (possibly) with the 'linear' clause.
3220   /// \return true if at least one linear variable is found that should be
3221   /// initialized with the value of the original variable, false otherwise.
3222   bool EmitOMPLinearClauseInit(const OMPLoopDirective &D);
3223 
3224   typedef const llvm::function_ref<void(CodeGenFunction & /*CGF*/,
3225                                         llvm::Function * /*OutlinedFn*/,
3226                                         const OMPTaskDataTy & /*Data*/)>
3227       TaskGenTy;
3228   void EmitOMPTaskBasedDirective(const OMPExecutableDirective &S,
3229                                  const OpenMPDirectiveKind CapturedRegion,
3230                                  const RegionCodeGenTy &BodyGen,
3231                                  const TaskGenTy &TaskGen, OMPTaskDataTy &Data);
3232   struct OMPTargetDataInfo {
3233     Address BasePointersArray = Address::invalid();
3234     Address PointersArray = Address::invalid();
3235     Address SizesArray = Address::invalid();
3236     unsigned NumberOfTargetItems = 0;
3237     explicit OMPTargetDataInfo() = default;
3238     OMPTargetDataInfo(Address BasePointersArray, Address PointersArray,
3239                       Address SizesArray, unsigned NumberOfTargetItems)
3240         : BasePointersArray(BasePointersArray), PointersArray(PointersArray),
3241           SizesArray(SizesArray), NumberOfTargetItems(NumberOfTargetItems) {}
3242   };
3243   void EmitOMPTargetTaskBasedDirective(const OMPExecutableDirective &S,
3244                                        const RegionCodeGenTy &BodyGen,
3245                                        OMPTargetDataInfo &InputInfo);
3246 
3247   void EmitOMPParallelDirective(const OMPParallelDirective &S);
3248   void EmitOMPSimdDirective(const OMPSimdDirective &S);
3249   void EmitOMPForDirective(const OMPForDirective &S);
3250   void EmitOMPForSimdDirective(const OMPForSimdDirective &S);
3251   void EmitOMPSectionsDirective(const OMPSectionsDirective &S);
3252   void EmitOMPSectionDirective(const OMPSectionDirective &S);
3253   void EmitOMPSingleDirective(const OMPSingleDirective &S);
3254   void EmitOMPMasterDirective(const OMPMasterDirective &S);
3255   void EmitOMPCriticalDirective(const OMPCriticalDirective &S);
3256   void EmitOMPParallelForDirective(const OMPParallelForDirective &S);
3257   void EmitOMPParallelForSimdDirective(const OMPParallelForSimdDirective &S);
3258   void EmitOMPParallelSectionsDirective(const OMPParallelSectionsDirective &S);
3259   void EmitOMPParallelMasterDirective(const OMPParallelMasterDirective &S);
3260   void EmitOMPTaskDirective(const OMPTaskDirective &S);
3261   void EmitOMPTaskyieldDirective(const OMPTaskyieldDirective &S);
3262   void EmitOMPBarrierDirective(const OMPBarrierDirective &S);
3263   void EmitOMPTaskwaitDirective(const OMPTaskwaitDirective &S);
3264   void EmitOMPTaskgroupDirective(const OMPTaskgroupDirective &S);
3265   void EmitOMPFlushDirective(const OMPFlushDirective &S);
3266   void EmitOMPDepobjDirective(const OMPDepobjDirective &S);
3267   void EmitOMPOrderedDirective(const OMPOrderedDirective &S);
3268   void EmitOMPAtomicDirective(const OMPAtomicDirective &S);
3269   void EmitOMPTargetDirective(const OMPTargetDirective &S);
3270   void EmitOMPTargetDataDirective(const OMPTargetDataDirective &S);
3271   void EmitOMPTargetEnterDataDirective(const OMPTargetEnterDataDirective &S);
3272   void EmitOMPTargetExitDataDirective(const OMPTargetExitDataDirective &S);
3273   void EmitOMPTargetUpdateDirective(const OMPTargetUpdateDirective &S);
3274   void EmitOMPTargetParallelDirective(const OMPTargetParallelDirective &S);
3275   void
3276   EmitOMPTargetParallelForDirective(const OMPTargetParallelForDirective &S);
3277   void EmitOMPTeamsDirective(const OMPTeamsDirective &S);
3278   void
3279   EmitOMPCancellationPointDirective(const OMPCancellationPointDirective &S);
3280   void EmitOMPCancelDirective(const OMPCancelDirective &S);
3281   void EmitOMPTaskLoopBasedDirective(const OMPLoopDirective &S);
3282   void EmitOMPTaskLoopDirective(const OMPTaskLoopDirective &S);
3283   void EmitOMPTaskLoopSimdDirective(const OMPTaskLoopSimdDirective &S);
3284   void EmitOMPMasterTaskLoopDirective(const OMPMasterTaskLoopDirective &S);
3285   void
3286   EmitOMPMasterTaskLoopSimdDirective(const OMPMasterTaskLoopSimdDirective &S);
3287   void EmitOMPParallelMasterTaskLoopDirective(
3288       const OMPParallelMasterTaskLoopDirective &S);
3289   void EmitOMPParallelMasterTaskLoopSimdDirective(
3290       const OMPParallelMasterTaskLoopSimdDirective &S);
3291   void EmitOMPDistributeDirective(const OMPDistributeDirective &S);
3292   void EmitOMPDistributeParallelForDirective(
3293       const OMPDistributeParallelForDirective &S);
3294   void EmitOMPDistributeParallelForSimdDirective(
3295       const OMPDistributeParallelForSimdDirective &S);
3296   void EmitOMPDistributeSimdDirective(const OMPDistributeSimdDirective &S);
3297   void EmitOMPTargetParallelForSimdDirective(
3298       const OMPTargetParallelForSimdDirective &S);
3299   void EmitOMPTargetSimdDirective(const OMPTargetSimdDirective &S);
3300   void EmitOMPTeamsDistributeDirective(const OMPTeamsDistributeDirective &S);
3301   void
3302   EmitOMPTeamsDistributeSimdDirective(const OMPTeamsDistributeSimdDirective &S);
3303   void EmitOMPTeamsDistributeParallelForSimdDirective(
3304       const OMPTeamsDistributeParallelForSimdDirective &S);
3305   void EmitOMPTeamsDistributeParallelForDirective(
3306       const OMPTeamsDistributeParallelForDirective &S);
3307   void EmitOMPTargetTeamsDirective(const OMPTargetTeamsDirective &S);
3308   void EmitOMPTargetTeamsDistributeDirective(
3309       const OMPTargetTeamsDistributeDirective &S);
3310   void EmitOMPTargetTeamsDistributeParallelForDirective(
3311       const OMPTargetTeamsDistributeParallelForDirective &S);
3312   void EmitOMPTargetTeamsDistributeParallelForSimdDirective(
3313       const OMPTargetTeamsDistributeParallelForSimdDirective &S);
3314   void EmitOMPTargetTeamsDistributeSimdDirective(
3315       const OMPTargetTeamsDistributeSimdDirective &S);
3316 
3317   /// Emit device code for the target directive.
3318   static void EmitOMPTargetDeviceFunction(CodeGenModule &CGM,
3319                                           StringRef ParentName,
3320                                           const OMPTargetDirective &S);
3321   static void
3322   EmitOMPTargetParallelDeviceFunction(CodeGenModule &CGM, StringRef ParentName,
3323                                       const OMPTargetParallelDirective &S);
3324   /// Emit device code for the target parallel for directive.
3325   static void EmitOMPTargetParallelForDeviceFunction(
3326       CodeGenModule &CGM, StringRef ParentName,
3327       const OMPTargetParallelForDirective &S);
3328   /// Emit device code for the target parallel for simd directive.
3329   static void EmitOMPTargetParallelForSimdDeviceFunction(
3330       CodeGenModule &CGM, StringRef ParentName,
3331       const OMPTargetParallelForSimdDirective &S);
3332   /// Emit device code for the target teams directive.
3333   static void
3334   EmitOMPTargetTeamsDeviceFunction(CodeGenModule &CGM, StringRef ParentName,
3335                                    const OMPTargetTeamsDirective &S);
3336   /// Emit device code for the target teams distribute directive.
3337   static void EmitOMPTargetTeamsDistributeDeviceFunction(
3338       CodeGenModule &CGM, StringRef ParentName,
3339       const OMPTargetTeamsDistributeDirective &S);
3340   /// Emit device code for the target teams distribute simd directive.
3341   static void EmitOMPTargetTeamsDistributeSimdDeviceFunction(
3342       CodeGenModule &CGM, StringRef ParentName,
3343       const OMPTargetTeamsDistributeSimdDirective &S);
3344   /// Emit device code for the target simd directive.
3345   static void EmitOMPTargetSimdDeviceFunction(CodeGenModule &CGM,
3346                                               StringRef ParentName,
3347                                               const OMPTargetSimdDirective &S);
3348   /// Emit device code for the target teams distribute parallel for simd
3349   /// directive.
3350   static void EmitOMPTargetTeamsDistributeParallelForSimdDeviceFunction(
3351       CodeGenModule &CGM, StringRef ParentName,
3352       const OMPTargetTeamsDistributeParallelForSimdDirective &S);
3353 
3354   static void EmitOMPTargetTeamsDistributeParallelForDeviceFunction(
3355       CodeGenModule &CGM, StringRef ParentName,
3356       const OMPTargetTeamsDistributeParallelForDirective &S);
3357   /// Emit inner loop of the worksharing/simd construct.
3358   ///
3359   /// \param S Directive, for which the inner loop must be emitted.
3360   /// \param RequiresCleanup true, if directive has some associated private
3361   /// variables.
3362   /// \param LoopCond Bollean condition for loop continuation.
3363   /// \param IncExpr Increment expression for loop control variable.
3364   /// \param BodyGen Generator for the inner body of the inner loop.
3365   /// \param PostIncGen Genrator for post-increment code (required for ordered
3366   /// loop directvies).
3367   void EmitOMPInnerLoop(
3368       const Stmt &S, bool RequiresCleanup, const Expr *LoopCond,
3369       const Expr *IncExpr,
3370       const llvm::function_ref<void(CodeGenFunction &)> BodyGen,
3371       const llvm::function_ref<void(CodeGenFunction &)> PostIncGen);
3372 
3373   JumpDest getOMPCancelDestination(OpenMPDirectiveKind Kind);
3374   /// Emit initial code for loop counters of loop-based directives.
3375   void EmitOMPPrivateLoopCounters(const OMPLoopDirective &S,
3376                                   OMPPrivateScope &LoopScope);
3377 
3378   /// Helper for the OpenMP loop directives.
3379   void EmitOMPLoopBody(const OMPLoopDirective &D, JumpDest LoopExit);
3380 
3381   /// Emit code for the worksharing loop-based directive.
3382   /// \return true, if this construct has any lastprivate clause, false -
3383   /// otherwise.
3384   bool EmitOMPWorksharingLoop(const OMPLoopDirective &S, Expr *EUB,
3385                               const CodeGenLoopBoundsTy &CodeGenLoopBounds,
3386                               const CodeGenDispatchBoundsTy &CGDispatchBounds);
3387 
3388   /// Emit code for the distribute loop-based directive.
3389   void EmitOMPDistributeLoop(const OMPLoopDirective &S,
3390                              const CodeGenLoopTy &CodeGenLoop, Expr *IncExpr);
3391 
3392   /// Helpers for the OpenMP loop directives.
3393   void EmitOMPSimdInit(const OMPLoopDirective &D, bool IsMonotonic = false);
3394   void EmitOMPSimdFinal(
3395       const OMPLoopDirective &D,
3396       const llvm::function_ref<llvm::Value *(CodeGenFunction &)> CondGen);
3397 
3398   /// Emits the lvalue for the expression with possibly captured variable.
3399   LValue EmitOMPSharedLValue(const Expr *E);
3400 
3401 private:
3402   /// Helpers for blocks.
3403   llvm::Value *EmitBlockLiteral(const CGBlockInfo &Info);
3404 
3405   /// struct with the values to be passed to the OpenMP loop-related functions
3406   struct OMPLoopArguments {
3407     /// loop lower bound
3408     Address LB = Address::invalid();
3409     /// loop upper bound
3410     Address UB = Address::invalid();
3411     /// loop stride
3412     Address ST = Address::invalid();
3413     /// isLastIteration argument for runtime functions
3414     Address IL = Address::invalid();
3415     /// Chunk value generated by sema
3416     llvm::Value *Chunk = nullptr;
3417     /// EnsureUpperBound
3418     Expr *EUB = nullptr;
3419     /// IncrementExpression
3420     Expr *IncExpr = nullptr;
3421     /// Loop initialization
3422     Expr *Init = nullptr;
3423     /// Loop exit condition
3424     Expr *Cond = nullptr;
3425     /// Update of LB after a whole chunk has been executed
3426     Expr *NextLB = nullptr;
3427     /// Update of UB after a whole chunk has been executed
3428     Expr *NextUB = nullptr;
3429     OMPLoopArguments() = default;
3430     OMPLoopArguments(Address LB, Address UB, Address ST, Address IL,
3431                      llvm::Value *Chunk = nullptr, Expr *EUB = nullptr,
3432                      Expr *IncExpr = nullptr, Expr *Init = nullptr,
3433                      Expr *Cond = nullptr, Expr *NextLB = nullptr,
3434                      Expr *NextUB = nullptr)
3435         : LB(LB), UB(UB), ST(ST), IL(IL), Chunk(Chunk), EUB(EUB),
3436           IncExpr(IncExpr), Init(Init), Cond(Cond), NextLB(NextLB),
3437           NextUB(NextUB) {}
3438   };
3439   void EmitOMPOuterLoop(bool DynamicOrOrdered, bool IsMonotonic,
3440                         const OMPLoopDirective &S, OMPPrivateScope &LoopScope,
3441                         const OMPLoopArguments &LoopArgs,
3442                         const CodeGenLoopTy &CodeGenLoop,
3443                         const CodeGenOrderedTy &CodeGenOrdered);
3444   void EmitOMPForOuterLoop(const OpenMPScheduleTy &ScheduleKind,
3445                            bool IsMonotonic, const OMPLoopDirective &S,
3446                            OMPPrivateScope &LoopScope, bool Ordered,
3447                            const OMPLoopArguments &LoopArgs,
3448                            const CodeGenDispatchBoundsTy &CGDispatchBounds);
3449   void EmitOMPDistributeOuterLoop(OpenMPDistScheduleClauseKind ScheduleKind,
3450                                   const OMPLoopDirective &S,
3451                                   OMPPrivateScope &LoopScope,
3452                                   const OMPLoopArguments &LoopArgs,
3453                                   const CodeGenLoopTy &CodeGenLoopContent);
3454   /// Emit code for sections directive.
3455   void EmitSections(const OMPExecutableDirective &S);
3456 
3457 public:
3458 
3459   //===--------------------------------------------------------------------===//
3460   //                         LValue Expression Emission
3461   //===--------------------------------------------------------------------===//
3462 
3463   /// GetUndefRValue - Get an appropriate 'undef' rvalue for the given type.
3464   RValue GetUndefRValue(QualType Ty);
3465 
3466   /// EmitUnsupportedRValue - Emit a dummy r-value using the type of E
3467   /// and issue an ErrorUnsupported style diagnostic (using the
3468   /// provided Name).
3469   RValue EmitUnsupportedRValue(const Expr *E,
3470                                const char *Name);
3471 
3472   /// EmitUnsupportedLValue - Emit a dummy l-value using the type of E and issue
3473   /// an ErrorUnsupported style diagnostic (using the provided Name).
3474   LValue EmitUnsupportedLValue(const Expr *E,
3475                                const char *Name);
3476 
3477   /// EmitLValue - Emit code to compute a designator that specifies the location
3478   /// of the expression.
3479   ///
3480   /// This can return one of two things: a simple address or a bitfield
3481   /// reference.  In either case, the LLVM Value* in the LValue structure is
3482   /// guaranteed to be an LLVM pointer type.
3483   ///
3484   /// If this returns a bitfield reference, nothing about the pointee type of
3485   /// the LLVM value is known: For example, it may not be a pointer to an
3486   /// integer.
3487   ///
3488   /// If this returns a normal address, and if the lvalue's C type is fixed
3489   /// size, this method guarantees that the returned pointer type will point to
3490   /// an LLVM type of the same size of the lvalue's type.  If the lvalue has a
3491   /// variable length type, this is not possible.
3492   ///
3493   LValue EmitLValue(const Expr *E);
3494 
3495   /// Same as EmitLValue but additionally we generate checking code to
3496   /// guard against undefined behavior.  This is only suitable when we know
3497   /// that the address will be used to access the object.
3498   LValue EmitCheckedLValue(const Expr *E, TypeCheckKind TCK);
3499 
3500   RValue convertTempToRValue(Address addr, QualType type,
3501                              SourceLocation Loc);
3502 
3503   void EmitAtomicInit(Expr *E, LValue lvalue);
3504 
3505   bool LValueIsSuitableForInlineAtomic(LValue Src);
3506 
3507   RValue EmitAtomicLoad(LValue LV, SourceLocation SL,
3508                         AggValueSlot Slot = AggValueSlot::ignored());
3509 
3510   RValue EmitAtomicLoad(LValue lvalue, SourceLocation loc,
3511                         llvm::AtomicOrdering AO, bool IsVolatile = false,
3512                         AggValueSlot slot = AggValueSlot::ignored());
3513 
3514   void EmitAtomicStore(RValue rvalue, LValue lvalue, bool isInit);
3515 
3516   void EmitAtomicStore(RValue rvalue, LValue lvalue, llvm::AtomicOrdering AO,
3517                        bool IsVolatile, bool isInit);
3518 
3519   std::pair<RValue, llvm::Value *> EmitAtomicCompareExchange(
3520       LValue Obj, RValue Expected, RValue Desired, SourceLocation Loc,
3521       llvm::AtomicOrdering Success =
3522           llvm::AtomicOrdering::SequentiallyConsistent,
3523       llvm::AtomicOrdering Failure =
3524           llvm::AtomicOrdering::SequentiallyConsistent,
3525       bool IsWeak = false, AggValueSlot Slot = AggValueSlot::ignored());
3526 
3527   void EmitAtomicUpdate(LValue LVal, llvm::AtomicOrdering AO,
3528                         const llvm::function_ref<RValue(RValue)> &UpdateOp,
3529                         bool IsVolatile);
3530 
3531   /// EmitToMemory - Change a scalar value from its value
3532   /// representation to its in-memory representation.
3533   llvm::Value *EmitToMemory(llvm::Value *Value, QualType Ty);
3534 
3535   /// EmitFromMemory - Change a scalar value from its memory
3536   /// representation to its value representation.
3537   llvm::Value *EmitFromMemory(llvm::Value *Value, QualType Ty);
3538 
3539   /// Check if the scalar \p Value is within the valid range for the given
3540   /// type \p Ty.
3541   ///
3542   /// Returns true if a check is needed (even if the range is unknown).
3543   bool EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
3544                             SourceLocation Loc);
3545 
3546   /// EmitLoadOfScalar - Load a scalar value from an address, taking
3547   /// care to appropriately convert from the memory representation to
3548   /// the LLVM value representation.
3549   llvm::Value *EmitLoadOfScalar(Address Addr, bool Volatile, QualType Ty,
3550                                 SourceLocation Loc,
3551                                 AlignmentSource Source = AlignmentSource::Type,
3552                                 bool isNontemporal = false) {
3553     return EmitLoadOfScalar(Addr, Volatile, Ty, Loc, LValueBaseInfo(Source),
3554                             CGM.getTBAAAccessInfo(Ty), isNontemporal);
3555   }
3556 
3557   llvm::Value *EmitLoadOfScalar(Address Addr, bool Volatile, QualType Ty,
3558                                 SourceLocation Loc, LValueBaseInfo BaseInfo,
3559                                 TBAAAccessInfo TBAAInfo,
3560                                 bool isNontemporal = false);
3561 
3562   /// EmitLoadOfScalar - Load a scalar value from an address, taking
3563   /// care to appropriately convert from the memory representation to
3564   /// the LLVM value representation.  The l-value must be a simple
3565   /// l-value.
3566   llvm::Value *EmitLoadOfScalar(LValue lvalue, SourceLocation Loc);
3567 
3568   /// EmitStoreOfScalar - Store a scalar value to an address, taking
3569   /// care to appropriately convert from the memory representation to
3570   /// the LLVM value representation.
3571   void EmitStoreOfScalar(llvm::Value *Value, Address Addr,
3572                          bool Volatile, QualType Ty,
3573                          AlignmentSource Source = AlignmentSource::Type,
3574                          bool isInit = false, bool isNontemporal = false) {
3575     EmitStoreOfScalar(Value, Addr, Volatile, Ty, LValueBaseInfo(Source),
3576                       CGM.getTBAAAccessInfo(Ty), isInit, isNontemporal);
3577   }
3578 
3579   void EmitStoreOfScalar(llvm::Value *Value, Address Addr,
3580                          bool Volatile, QualType Ty,
3581                          LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo,
3582                          bool isInit = false, bool isNontemporal = false);
3583 
3584   /// EmitStoreOfScalar - Store a scalar value to an address, taking
3585   /// care to appropriately convert from the memory representation to
3586   /// the LLVM value representation.  The l-value must be a simple
3587   /// l-value.  The isInit flag indicates whether this is an initialization.
3588   /// If so, atomic qualifiers are ignored and the store is always non-atomic.
3589   void EmitStoreOfScalar(llvm::Value *value, LValue lvalue, bool isInit=false);
3590 
3591   /// EmitLoadOfLValue - Given an expression that represents a value lvalue,
3592   /// this method emits the address of the lvalue, then loads the result as an
3593   /// rvalue, returning the rvalue.
3594   RValue EmitLoadOfLValue(LValue V, SourceLocation Loc);
3595   RValue EmitLoadOfExtVectorElementLValue(LValue V);
3596   RValue EmitLoadOfBitfieldLValue(LValue LV, SourceLocation Loc);
3597   RValue EmitLoadOfGlobalRegLValue(LValue LV);
3598 
3599   /// EmitStoreThroughLValue - Store the specified rvalue into the specified
3600   /// lvalue, where both are guaranteed to the have the same type, and that type
3601   /// is 'Ty'.
3602   void EmitStoreThroughLValue(RValue Src, LValue Dst, bool isInit = false);
3603   void EmitStoreThroughExtVectorComponentLValue(RValue Src, LValue Dst);
3604   void EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst);
3605 
3606   /// EmitStoreThroughBitfieldLValue - Store Src into Dst with same constraints
3607   /// as EmitStoreThroughLValue.
3608   ///
3609   /// \param Result [out] - If non-null, this will be set to a Value* for the
3610   /// bit-field contents after the store, appropriate for use as the result of
3611   /// an assignment to the bit-field.
3612   void EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
3613                                       llvm::Value **Result=nullptr);
3614 
3615   /// Emit an l-value for an assignment (simple or compound) of complex type.
3616   LValue EmitComplexAssignmentLValue(const BinaryOperator *E);
3617   LValue EmitComplexCompoundAssignmentLValue(const CompoundAssignOperator *E);
3618   LValue EmitScalarCompoundAssignWithComplex(const CompoundAssignOperator *E,
3619                                              llvm::Value *&Result);
3620 
3621   // Note: only available for agg return types
3622   LValue EmitBinaryOperatorLValue(const BinaryOperator *E);
3623   LValue EmitCompoundAssignmentLValue(const CompoundAssignOperator *E);
3624   // Note: only available for agg return types
3625   LValue EmitCallExprLValue(const CallExpr *E);
3626   // Note: only available for agg return types
3627   LValue EmitVAArgExprLValue(const VAArgExpr *E);
3628   LValue EmitDeclRefLValue(const DeclRefExpr *E);
3629   LValue EmitStringLiteralLValue(const StringLiteral *E);
3630   LValue EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E);
3631   LValue EmitPredefinedLValue(const PredefinedExpr *E);
3632   LValue EmitUnaryOpLValue(const UnaryOperator *E);
3633   LValue EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3634                                 bool Accessed = false);
3635   LValue EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3636                                  bool IsLowerBound = true);
3637   LValue EmitExtVectorElementExpr(const ExtVectorElementExpr *E);
3638   LValue EmitMemberExpr(const MemberExpr *E);
3639   LValue EmitObjCIsaExpr(const ObjCIsaExpr *E);
3640   LValue EmitCompoundLiteralLValue(const CompoundLiteralExpr *E);
3641   LValue EmitInitListLValue(const InitListExpr *E);
3642   LValue EmitConditionalOperatorLValue(const AbstractConditionalOperator *E);
3643   LValue EmitCastLValue(const CastExpr *E);
3644   LValue EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E);
3645   LValue EmitOpaqueValueLValue(const OpaqueValueExpr *e);
3646 
3647   Address EmitExtVectorElementLValue(LValue V);
3648 
3649   RValue EmitRValueForField(LValue LV, const FieldDecl *FD, SourceLocation Loc);
3650 
3651   Address EmitArrayToPointerDecay(const Expr *Array,
3652                                   LValueBaseInfo *BaseInfo = nullptr,
3653                                   TBAAAccessInfo *TBAAInfo = nullptr);
3654 
3655   class ConstantEmission {
3656     llvm::PointerIntPair<llvm::Constant*, 1, bool> ValueAndIsReference;
3657     ConstantEmission(llvm::Constant *C, bool isReference)
3658       : ValueAndIsReference(C, isReference) {}
3659   public:
3660     ConstantEmission() {}
3661     static ConstantEmission forReference(llvm::Constant *C) {
3662       return ConstantEmission(C, true);
3663     }
3664     static ConstantEmission forValue(llvm::Constant *C) {
3665       return ConstantEmission(C, false);
3666     }
3667 
3668     explicit operator bool() const {
3669       return ValueAndIsReference.getOpaqueValue() != nullptr;
3670     }
3671 
3672     bool isReference() const { return ValueAndIsReference.getInt(); }
3673     LValue getReferenceLValue(CodeGenFunction &CGF, Expr *refExpr) const {
3674       assert(isReference());
3675       return CGF.MakeNaturalAlignAddrLValue(ValueAndIsReference.getPointer(),
3676                                             refExpr->getType());
3677     }
3678 
3679     llvm::Constant *getValue() const {
3680       assert(!isReference());
3681       return ValueAndIsReference.getPointer();
3682     }
3683   };
3684 
3685   ConstantEmission tryEmitAsConstant(DeclRefExpr *refExpr);
3686   ConstantEmission tryEmitAsConstant(const MemberExpr *ME);
3687   llvm::Value *emitScalarConstant(const ConstantEmission &Constant, Expr *E);
3688 
3689   RValue EmitPseudoObjectRValue(const PseudoObjectExpr *e,
3690                                 AggValueSlot slot = AggValueSlot::ignored());
3691   LValue EmitPseudoObjectLValue(const PseudoObjectExpr *e);
3692 
3693   llvm::Value *EmitIvarOffset(const ObjCInterfaceDecl *Interface,
3694                               const ObjCIvarDecl *Ivar);
3695   LValue EmitLValueForField(LValue Base, const FieldDecl* Field);
3696   LValue EmitLValueForLambdaField(const FieldDecl *Field);
3697 
3698   /// EmitLValueForFieldInitialization - Like EmitLValueForField, except that
3699   /// if the Field is a reference, this will return the address of the reference
3700   /// and not the address of the value stored in the reference.
3701   LValue EmitLValueForFieldInitialization(LValue Base,
3702                                           const FieldDecl* Field);
3703 
3704   LValue EmitLValueForIvar(QualType ObjectTy,
3705                            llvm::Value* Base, const ObjCIvarDecl *Ivar,
3706                            unsigned CVRQualifiers);
3707 
3708   LValue EmitCXXConstructLValue(const CXXConstructExpr *E);
3709   LValue EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E);
3710   LValue EmitCXXTypeidLValue(const CXXTypeidExpr *E);
3711   LValue EmitCXXUuidofLValue(const CXXUuidofExpr *E);
3712 
3713   LValue EmitObjCMessageExprLValue(const ObjCMessageExpr *E);
3714   LValue EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E);
3715   LValue EmitStmtExprLValue(const StmtExpr *E);
3716   LValue EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E);
3717   LValue EmitObjCSelectorLValue(const ObjCSelectorExpr *E);
3718   void   EmitDeclRefExprDbgValue(const DeclRefExpr *E, const APValue &Init);
3719 
3720   //===--------------------------------------------------------------------===//
3721   //                         Scalar Expression Emission
3722   //===--------------------------------------------------------------------===//
3723 
3724   /// EmitCall - Generate a call of the given function, expecting the given
3725   /// result type, and using the given argument list which specifies both the
3726   /// LLVM arguments and the types they were derived from.
3727   RValue EmitCall(const CGFunctionInfo &CallInfo, const CGCallee &Callee,
3728                   ReturnValueSlot ReturnValue, const CallArgList &Args,
3729                   llvm::CallBase **callOrInvoke, SourceLocation Loc);
3730   RValue EmitCall(const CGFunctionInfo &CallInfo, const CGCallee &Callee,
3731                   ReturnValueSlot ReturnValue, const CallArgList &Args,
3732                   llvm::CallBase **callOrInvoke = nullptr) {
3733     return EmitCall(CallInfo, Callee, ReturnValue, Args, callOrInvoke,
3734                     SourceLocation());
3735   }
3736   RValue EmitCall(QualType FnType, const CGCallee &Callee, const CallExpr *E,
3737                   ReturnValueSlot ReturnValue, llvm::Value *Chain = nullptr);
3738   RValue EmitCallExpr(const CallExpr *E,
3739                       ReturnValueSlot ReturnValue = ReturnValueSlot());
3740   RValue EmitSimpleCallExpr(const CallExpr *E, ReturnValueSlot ReturnValue);
3741   CGCallee EmitCallee(const Expr *E);
3742 
3743   void checkTargetFeatures(const CallExpr *E, const FunctionDecl *TargetDecl);
3744   void checkTargetFeatures(SourceLocation Loc, const FunctionDecl *TargetDecl);
3745 
3746   llvm::CallInst *EmitRuntimeCall(llvm::FunctionCallee callee,
3747                                   const Twine &name = "");
3748   llvm::CallInst *EmitRuntimeCall(llvm::FunctionCallee callee,
3749                                   ArrayRef<llvm::Value *> args,
3750                                   const Twine &name = "");
3751   llvm::CallInst *EmitNounwindRuntimeCall(llvm::FunctionCallee callee,
3752                                           const Twine &name = "");
3753   llvm::CallInst *EmitNounwindRuntimeCall(llvm::FunctionCallee callee,
3754                                           ArrayRef<llvm::Value *> args,
3755                                           const Twine &name = "");
3756 
3757   SmallVector<llvm::OperandBundleDef, 1>
3758   getBundlesForFunclet(llvm::Value *Callee);
3759 
3760   llvm::CallBase *EmitCallOrInvoke(llvm::FunctionCallee Callee,
3761                                    ArrayRef<llvm::Value *> Args,
3762                                    const Twine &Name = "");
3763   llvm::CallBase *EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee,
3764                                           ArrayRef<llvm::Value *> args,
3765                                           const Twine &name = "");
3766   llvm::CallBase *EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee,
3767                                           const Twine &name = "");
3768   void EmitNoreturnRuntimeCallOrInvoke(llvm::FunctionCallee callee,
3769                                        ArrayRef<llvm::Value *> args);
3770 
3771   CGCallee BuildAppleKextVirtualCall(const CXXMethodDecl *MD,
3772                                      NestedNameSpecifier *Qual,
3773                                      llvm::Type *Ty);
3774 
3775   CGCallee BuildAppleKextVirtualDestructorCall(const CXXDestructorDecl *DD,
3776                                                CXXDtorType Type,
3777                                                const CXXRecordDecl *RD);
3778 
3779   // Return the copy constructor name with the prefix "__copy_constructor_"
3780   // removed.
3781   static std::string getNonTrivialCopyConstructorStr(QualType QT,
3782                                                      CharUnits Alignment,
3783                                                      bool IsVolatile,
3784                                                      ASTContext &Ctx);
3785 
3786   // Return the destructor name with the prefix "__destructor_" removed.
3787   static std::string getNonTrivialDestructorStr(QualType QT,
3788                                                 CharUnits Alignment,
3789                                                 bool IsVolatile,
3790                                                 ASTContext &Ctx);
3791 
3792   // These functions emit calls to the special functions of non-trivial C
3793   // structs.
3794   void defaultInitNonTrivialCStructVar(LValue Dst);
3795   void callCStructDefaultConstructor(LValue Dst);
3796   void callCStructDestructor(LValue Dst);
3797   void callCStructCopyConstructor(LValue Dst, LValue Src);
3798   void callCStructMoveConstructor(LValue Dst, LValue Src);
3799   void callCStructCopyAssignmentOperator(LValue Dst, LValue Src);
3800   void callCStructMoveAssignmentOperator(LValue Dst, LValue Src);
3801 
3802   RValue
3803   EmitCXXMemberOrOperatorCall(const CXXMethodDecl *Method,
3804                               const CGCallee &Callee,
3805                               ReturnValueSlot ReturnValue, llvm::Value *This,
3806                               llvm::Value *ImplicitParam,
3807                               QualType ImplicitParamTy, const CallExpr *E,
3808                               CallArgList *RtlArgs);
3809   RValue EmitCXXDestructorCall(GlobalDecl Dtor, const CGCallee &Callee,
3810                                llvm::Value *This, QualType ThisTy,
3811                                llvm::Value *ImplicitParam,
3812                                QualType ImplicitParamTy, const CallExpr *E);
3813   RValue EmitCXXMemberCallExpr(const CXXMemberCallExpr *E,
3814                                ReturnValueSlot ReturnValue);
3815   RValue EmitCXXMemberOrOperatorMemberCallExpr(const CallExpr *CE,
3816                                                const CXXMethodDecl *MD,
3817                                                ReturnValueSlot ReturnValue,
3818                                                bool HasQualifier,
3819                                                NestedNameSpecifier *Qualifier,
3820                                                bool IsArrow, const Expr *Base);
3821   // Compute the object pointer.
3822   Address EmitCXXMemberDataPointerAddress(const Expr *E, Address base,
3823                                           llvm::Value *memberPtr,
3824                                           const MemberPointerType *memberPtrType,
3825                                           LValueBaseInfo *BaseInfo = nullptr,
3826                                           TBAAAccessInfo *TBAAInfo = nullptr);
3827   RValue EmitCXXMemberPointerCallExpr(const CXXMemberCallExpr *E,
3828                                       ReturnValueSlot ReturnValue);
3829 
3830   RValue EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
3831                                        const CXXMethodDecl *MD,
3832                                        ReturnValueSlot ReturnValue);
3833   RValue EmitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E);
3834 
3835   RValue EmitCUDAKernelCallExpr(const CUDAKernelCallExpr *E,
3836                                 ReturnValueSlot ReturnValue);
3837 
3838   RValue EmitNVPTXDevicePrintfCallExpr(const CallExpr *E,
3839                                        ReturnValueSlot ReturnValue);
3840   RValue EmitAMDGPUDevicePrintfCallExpr(const CallExpr *E,
3841                                         ReturnValueSlot ReturnValue);
3842 
3843   RValue EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
3844                          const CallExpr *E, ReturnValueSlot ReturnValue);
3845 
3846   RValue emitRotate(const CallExpr *E, bool IsRotateRight);
3847 
3848   /// Emit IR for __builtin_os_log_format.
3849   RValue emitBuiltinOSLogFormat(const CallExpr &E);
3850 
3851   /// Emit IR for __builtin_is_aligned.
3852   RValue EmitBuiltinIsAligned(const CallExpr *E);
3853   /// Emit IR for __builtin_align_up/__builtin_align_down.
3854   RValue EmitBuiltinAlignTo(const CallExpr *E, bool AlignUp);
3855 
3856   llvm::Function *generateBuiltinOSLogHelperFunction(
3857       const analyze_os_log::OSLogBufferLayout &Layout,
3858       CharUnits BufferAlignment);
3859 
3860   RValue EmitBlockCallExpr(const CallExpr *E, ReturnValueSlot ReturnValue);
3861 
3862   /// EmitTargetBuiltinExpr - Emit the given builtin call. Returns 0 if the call
3863   /// is unhandled by the current target.
3864   llvm::Value *EmitTargetBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
3865                                      ReturnValueSlot ReturnValue);
3866 
3867   llvm::Value *EmitAArch64CompareBuiltinExpr(llvm::Value *Op, llvm::Type *Ty,
3868                                              const llvm::CmpInst::Predicate Fp,
3869                                              const llvm::CmpInst::Predicate Ip,
3870                                              const llvm::Twine &Name = "");
3871   llvm::Value *EmitARMBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
3872                                   ReturnValueSlot ReturnValue,
3873                                   llvm::Triple::ArchType Arch);
3874   llvm::Value *EmitARMMVEBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
3875                                      ReturnValueSlot ReturnValue,
3876                                      llvm::Triple::ArchType Arch);
3877   llvm::Value *EmitARMCDEBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
3878                                      ReturnValueSlot ReturnValue,
3879                                      llvm::Triple::ArchType Arch);
3880   llvm::Value *EmitCMSEClearRecord(llvm::Value *V, llvm::IntegerType *ITy,
3881                                    QualType RTy);
3882   llvm::Value *EmitCMSEClearRecord(llvm::Value *V, llvm::ArrayType *ATy,
3883                                    QualType RTy);
3884   llvm::Value *EmitCMSEClearFP16(llvm::Value *V);
3885 
3886   llvm::Value *EmitCommonNeonBuiltinExpr(unsigned BuiltinID,
3887                                          unsigned LLVMIntrinsic,
3888                                          unsigned AltLLVMIntrinsic,
3889                                          const char *NameHint,
3890                                          unsigned Modifier,
3891                                          const CallExpr *E,
3892                                          SmallVectorImpl<llvm::Value *> &Ops,
3893                                          Address PtrOp0, Address PtrOp1,
3894                                          llvm::Triple::ArchType Arch);
3895 
3896   llvm::Function *LookupNeonLLVMIntrinsic(unsigned IntrinsicID,
3897                                           unsigned Modifier, llvm::Type *ArgTy,
3898                                           const CallExpr *E);
3899   llvm::Value *EmitNeonCall(llvm::Function *F,
3900                             SmallVectorImpl<llvm::Value*> &O,
3901                             const char *name,
3902                             unsigned shift = 0, bool rightshift = false);
3903   llvm::Value *EmitNeonSplat(llvm::Value *V, llvm::Constant *Idx,
3904                              const llvm::ElementCount &Count);
3905   llvm::Value *EmitNeonSplat(llvm::Value *V, llvm::Constant *Idx);
3906   llvm::Value *EmitNeonShiftVector(llvm::Value *V, llvm::Type *Ty,
3907                                    bool negateForRightShift);
3908   llvm::Value *EmitNeonRShiftImm(llvm::Value *Vec, llvm::Value *Amt,
3909                                  llvm::Type *Ty, bool usgn, const char *name);
3910   llvm::Value *vectorWrapScalar16(llvm::Value *Op);
3911   /// SVEBuiltinMemEltTy - Returns the memory element type for this memory
3912   /// access builtin.  Only required if it can't be inferred from the base
3913   /// pointer operand.
3914   llvm::Type *SVEBuiltinMemEltTy(SVETypeFlags TypeFlags);
3915 
3916   SmallVector<llvm::Type *, 2> getSVEOverloadTypes(SVETypeFlags TypeFlags,
3917                                                    ArrayRef<llvm::Value *> Ops);
3918   llvm::Type *getEltType(SVETypeFlags TypeFlags);
3919   llvm::ScalableVectorType *getSVEType(const SVETypeFlags &TypeFlags);
3920   llvm::ScalableVectorType *getSVEPredType(SVETypeFlags TypeFlags);
3921   llvm::Value *EmitSVEAllTruePred(SVETypeFlags TypeFlags);
3922   llvm::Value *EmitSVEDupX(llvm::Value *Scalar);
3923   llvm::Value *EmitSVEPredicateCast(llvm::Value *Pred,
3924                                     llvm::ScalableVectorType *VTy);
3925   llvm::Value *EmitSVEGatherLoad(SVETypeFlags TypeFlags,
3926                                  llvm::SmallVectorImpl<llvm::Value *> &Ops,
3927                                  unsigned IntID);
3928   llvm::Value *EmitSVEScatterStore(SVETypeFlags TypeFlags,
3929                                    llvm::SmallVectorImpl<llvm::Value *> &Ops,
3930                                    unsigned IntID);
3931   llvm::Value *EmitSVEMaskedLoad(const CallExpr *, llvm::Type *ReturnTy,
3932                                  SmallVectorImpl<llvm::Value *> &Ops,
3933                                  unsigned BuiltinID, bool IsZExtReturn);
3934   llvm::Value *EmitSVEMaskedStore(const CallExpr *,
3935                                   SmallVectorImpl<llvm::Value *> &Ops,
3936                                   unsigned BuiltinID);
3937   llvm::Value *EmitSVEPrefetchLoad(SVETypeFlags TypeFlags,
3938                                    SmallVectorImpl<llvm::Value *> &Ops,
3939                                    unsigned BuiltinID);
3940   llvm::Value *EmitSVEGatherPrefetch(SVETypeFlags TypeFlags,
3941                                      SmallVectorImpl<llvm::Value *> &Ops,
3942                                      unsigned IntID);
3943   llvm::Value *EmitAArch64SVEBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3944 
3945   llvm::Value *EmitAArch64BuiltinExpr(unsigned BuiltinID, const CallExpr *E,
3946                                       llvm::Triple::ArchType Arch);
3947   llvm::Value *EmitBPFBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3948 
3949   llvm::Value *BuildVector(ArrayRef<llvm::Value*> Ops);
3950   llvm::Value *EmitX86BuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3951   llvm::Value *EmitPPCBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3952   llvm::Value *EmitAMDGPUBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3953   llvm::Value *EmitSystemZBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3954   llvm::Value *EmitNVPTXBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3955   llvm::Value *EmitWebAssemblyBuiltinExpr(unsigned BuiltinID,
3956                                           const CallExpr *E);
3957   llvm::Value *EmitHexagonBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3958 
3959 private:
3960   enum class MSVCIntrin;
3961 
3962 public:
3963   llvm::Value *EmitMSVCBuiltinExpr(MSVCIntrin BuiltinID, const CallExpr *E);
3964 
3965   llvm::Value *EmitBuiltinAvailable(ArrayRef<llvm::Value *> Args);
3966 
3967   llvm::Value *EmitObjCProtocolExpr(const ObjCProtocolExpr *E);
3968   llvm::Value *EmitObjCStringLiteral(const ObjCStringLiteral *E);
3969   llvm::Value *EmitObjCBoxedExpr(const ObjCBoxedExpr *E);
3970   llvm::Value *EmitObjCArrayLiteral(const ObjCArrayLiteral *E);
3971   llvm::Value *EmitObjCDictionaryLiteral(const ObjCDictionaryLiteral *E);
3972   llvm::Value *EmitObjCCollectionLiteral(const Expr *E,
3973                                 const ObjCMethodDecl *MethodWithObjects);
3974   llvm::Value *EmitObjCSelectorExpr(const ObjCSelectorExpr *E);
3975   RValue EmitObjCMessageExpr(const ObjCMessageExpr *E,
3976                              ReturnValueSlot Return = ReturnValueSlot());
3977 
3978   /// Retrieves the default cleanup kind for an ARC cleanup.
3979   /// Except under -fobjc-arc-eh, ARC cleanups are normal-only.
3980   CleanupKind getARCCleanupKind() {
3981     return CGM.getCodeGenOpts().ObjCAutoRefCountExceptions
3982              ? NormalAndEHCleanup : NormalCleanup;
3983   }
3984 
3985   // ARC primitives.
3986   void EmitARCInitWeak(Address addr, llvm::Value *value);
3987   void EmitARCDestroyWeak(Address addr);
3988   llvm::Value *EmitARCLoadWeak(Address addr);
3989   llvm::Value *EmitARCLoadWeakRetained(Address addr);
3990   llvm::Value *EmitARCStoreWeak(Address addr, llvm::Value *value, bool ignored);
3991   void emitARCCopyAssignWeak(QualType Ty, Address DstAddr, Address SrcAddr);
3992   void emitARCMoveAssignWeak(QualType Ty, Address DstAddr, Address SrcAddr);
3993   void EmitARCCopyWeak(Address dst, Address src);
3994   void EmitARCMoveWeak(Address dst, Address src);
3995   llvm::Value *EmitARCRetainAutorelease(QualType type, llvm::Value *value);
3996   llvm::Value *EmitARCRetainAutoreleaseNonBlock(llvm::Value *value);
3997   llvm::Value *EmitARCStoreStrong(LValue lvalue, llvm::Value *value,
3998                                   bool resultIgnored);
3999   llvm::Value *EmitARCStoreStrongCall(Address addr, llvm::Value *value,
4000                                       bool resultIgnored);
4001   llvm::Value *EmitARCRetain(QualType type, llvm::Value *value);
4002   llvm::Value *EmitARCRetainNonBlock(llvm::Value *value);
4003   llvm::Value *EmitARCRetainBlock(llvm::Value *value, bool mandatory);
4004   void EmitARCDestroyStrong(Address addr, ARCPreciseLifetime_t precise);
4005   void EmitARCRelease(llvm::Value *value, ARCPreciseLifetime_t precise);
4006   llvm::Value *EmitARCAutorelease(llvm::Value *value);
4007   llvm::Value *EmitARCAutoreleaseReturnValue(llvm::Value *value);
4008   llvm::Value *EmitARCRetainAutoreleaseReturnValue(llvm::Value *value);
4009   llvm::Value *EmitARCRetainAutoreleasedReturnValue(llvm::Value *value);
4010   llvm::Value *EmitARCUnsafeClaimAutoreleasedReturnValue(llvm::Value *value);
4011 
4012   llvm::Value *EmitObjCAutorelease(llvm::Value *value, llvm::Type *returnType);
4013   llvm::Value *EmitObjCRetainNonBlock(llvm::Value *value,
4014                                       llvm::Type *returnType);
4015   void EmitObjCRelease(llvm::Value *value, ARCPreciseLifetime_t precise);
4016 
4017   std::pair<LValue,llvm::Value*>
4018   EmitARCStoreAutoreleasing(const BinaryOperator *e);
4019   std::pair<LValue,llvm::Value*>
4020   EmitARCStoreStrong(const BinaryOperator *e, bool ignored);
4021   std::pair<LValue,llvm::Value*>
4022   EmitARCStoreUnsafeUnretained(const BinaryOperator *e, bool ignored);
4023 
4024   llvm::Value *EmitObjCAlloc(llvm::Value *value,
4025                              llvm::Type *returnType);
4026   llvm::Value *EmitObjCAllocWithZone(llvm::Value *value,
4027                                      llvm::Type *returnType);
4028   llvm::Value *EmitObjCAllocInit(llvm::Value *value, llvm::Type *resultType);
4029 
4030   llvm::Value *EmitObjCThrowOperand(const Expr *expr);
4031   llvm::Value *EmitObjCConsumeObject(QualType T, llvm::Value *Ptr);
4032   llvm::Value *EmitObjCExtendObjectLifetime(QualType T, llvm::Value *Ptr);
4033 
4034   llvm::Value *EmitARCExtendBlockObject(const Expr *expr);
4035   llvm::Value *EmitARCReclaimReturnedObject(const Expr *e,
4036                                             bool allowUnsafeClaim);
4037   llvm::Value *EmitARCRetainScalarExpr(const Expr *expr);
4038   llvm::Value *EmitARCRetainAutoreleaseScalarExpr(const Expr *expr);
4039   llvm::Value *EmitARCUnsafeUnretainedScalarExpr(const Expr *expr);
4040 
4041   void EmitARCIntrinsicUse(ArrayRef<llvm::Value*> values);
4042 
4043   static Destroyer destroyARCStrongImprecise;
4044   static Destroyer destroyARCStrongPrecise;
4045   static Destroyer destroyARCWeak;
4046   static Destroyer emitARCIntrinsicUse;
4047   static Destroyer destroyNonTrivialCStruct;
4048 
4049   void EmitObjCAutoreleasePoolPop(llvm::Value *Ptr);
4050   llvm::Value *EmitObjCAutoreleasePoolPush();
4051   llvm::Value *EmitObjCMRRAutoreleasePoolPush();
4052   void EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr);
4053   void EmitObjCMRRAutoreleasePoolPop(llvm::Value *Ptr);
4054 
4055   /// Emits a reference binding to the passed in expression.
4056   RValue EmitReferenceBindingToExpr(const Expr *E);
4057 
4058   //===--------------------------------------------------------------------===//
4059   //                           Expression Emission
4060   //===--------------------------------------------------------------------===//
4061 
4062   // Expressions are broken into three classes: scalar, complex, aggregate.
4063 
4064   /// EmitScalarExpr - Emit the computation of the specified expression of LLVM
4065   /// scalar type, returning the result.
4066   llvm::Value *EmitScalarExpr(const Expr *E , bool IgnoreResultAssign = false);
4067 
4068   /// Emit a conversion from the specified type to the specified destination
4069   /// type, both of which are LLVM scalar types.
4070   llvm::Value *EmitScalarConversion(llvm::Value *Src, QualType SrcTy,
4071                                     QualType DstTy, SourceLocation Loc);
4072 
4073   /// Emit a conversion from the specified complex type to the specified
4074   /// destination type, where the destination type is an LLVM scalar type.
4075   llvm::Value *EmitComplexToScalarConversion(ComplexPairTy Src, QualType SrcTy,
4076                                              QualType DstTy,
4077                                              SourceLocation Loc);
4078 
4079   /// EmitAggExpr - Emit the computation of the specified expression
4080   /// of aggregate type.  The result is computed into the given slot,
4081   /// which may be null to indicate that the value is not needed.
4082   void EmitAggExpr(const Expr *E, AggValueSlot AS);
4083 
4084   /// EmitAggExprToLValue - Emit the computation of the specified expression of
4085   /// aggregate type into a temporary LValue.
4086   LValue EmitAggExprToLValue(const Expr *E);
4087 
4088   /// EmitExtendGCLifetime - Given a pointer to an Objective-C object,
4089   /// make sure it survives garbage collection until this point.
4090   void EmitExtendGCLifetime(llvm::Value *object);
4091 
4092   /// EmitComplexExpr - Emit the computation of the specified expression of
4093   /// complex type, returning the result.
4094   ComplexPairTy EmitComplexExpr(const Expr *E,
4095                                 bool IgnoreReal = false,
4096                                 bool IgnoreImag = false);
4097 
4098   /// EmitComplexExprIntoLValue - Emit the given expression of complex
4099   /// type and place its result into the specified l-value.
4100   void EmitComplexExprIntoLValue(const Expr *E, LValue dest, bool isInit);
4101 
4102   /// EmitStoreOfComplex - Store a complex number into the specified l-value.
4103   void EmitStoreOfComplex(ComplexPairTy V, LValue dest, bool isInit);
4104 
4105   /// EmitLoadOfComplex - Load a complex number from the specified l-value.
4106   ComplexPairTy EmitLoadOfComplex(LValue src, SourceLocation loc);
4107 
4108   Address emitAddrOfRealComponent(Address complex, QualType complexType);
4109   Address emitAddrOfImagComponent(Address complex, QualType complexType);
4110 
4111   /// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
4112   /// global variable that has already been created for it.  If the initializer
4113   /// has a different type than GV does, this may free GV and return a different
4114   /// one.  Otherwise it just returns GV.
4115   llvm::GlobalVariable *
4116   AddInitializerToStaticVarDecl(const VarDecl &D,
4117                                 llvm::GlobalVariable *GV);
4118 
4119   // Emit an @llvm.invariant.start call for the given memory region.
4120   void EmitInvariantStart(llvm::Constant *Addr, CharUnits Size);
4121 
4122   /// EmitCXXGlobalVarDeclInit - Create the initializer for a C++
4123   /// variable with global storage.
4124   void EmitCXXGlobalVarDeclInit(const VarDecl &D, llvm::Constant *DeclPtr,
4125                                 bool PerformInit);
4126 
4127   llvm::Function *createAtExitStub(const VarDecl &VD, llvm::FunctionCallee Dtor,
4128                                    llvm::Constant *Addr);
4129 
4130   /// Call atexit() with a function that passes the given argument to
4131   /// the given function.
4132   void registerGlobalDtorWithAtExit(const VarDecl &D, llvm::FunctionCallee fn,
4133                                     llvm::Constant *addr);
4134 
4135   /// Call atexit() with function dtorStub.
4136   void registerGlobalDtorWithAtExit(llvm::Constant *dtorStub);
4137 
4138   /// Emit code in this function to perform a guarded variable
4139   /// initialization.  Guarded initializations are used when it's not
4140   /// possible to prove that an initialization will be done exactly
4141   /// once, e.g. with a static local variable or a static data member
4142   /// of a class template.
4143   void EmitCXXGuardedInit(const VarDecl &D, llvm::GlobalVariable *DeclPtr,
4144                           bool PerformInit);
4145 
4146   enum class GuardKind { VariableGuard, TlsGuard };
4147 
4148   /// Emit a branch to select whether or not to perform guarded initialization.
4149   void EmitCXXGuardedInitBranch(llvm::Value *NeedsInit,
4150                                 llvm::BasicBlock *InitBlock,
4151                                 llvm::BasicBlock *NoInitBlock,
4152                                 GuardKind Kind, const VarDecl *D);
4153 
4154   /// GenerateCXXGlobalInitFunc - Generates code for initializing global
4155   /// variables.
4156   void
4157   GenerateCXXGlobalInitFunc(llvm::Function *Fn,
4158                             ArrayRef<llvm::Function *> CXXThreadLocals,
4159                             ConstantAddress Guard = ConstantAddress::invalid());
4160 
4161   /// GenerateCXXGlobalDtorsFunc - Generates code for destroying global
4162   /// variables.
4163   void GenerateCXXGlobalDtorsFunc(
4164       llvm::Function *Fn,
4165       const std::vector<std::tuple<llvm::FunctionType *, llvm::WeakTrackingVH,
4166                                    llvm::Constant *>> &DtorsAndObjects);
4167 
4168   void GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn,
4169                                         const VarDecl *D,
4170                                         llvm::GlobalVariable *Addr,
4171                                         bool PerformInit);
4172 
4173   void EmitCXXConstructExpr(const CXXConstructExpr *E, AggValueSlot Dest);
4174 
4175   void EmitSynthesizedCXXCopyCtor(Address Dest, Address Src, const Expr *Exp);
4176 
4177   void enterFullExpression(const FullExpr *E) {
4178     if (const auto *EWC = dyn_cast<ExprWithCleanups>(E))
4179       if (EWC->getNumObjects() == 0)
4180         return;
4181     enterNonTrivialFullExpression(E);
4182   }
4183   void enterNonTrivialFullExpression(const FullExpr *E);
4184 
4185   void EmitCXXThrowExpr(const CXXThrowExpr *E, bool KeepInsertionPoint = true);
4186 
4187   RValue EmitAtomicExpr(AtomicExpr *E);
4188 
4189   //===--------------------------------------------------------------------===//
4190   //                         Annotations Emission
4191   //===--------------------------------------------------------------------===//
4192 
4193   /// Emit an annotation call (intrinsic).
4194   llvm::Value *EmitAnnotationCall(llvm::Function *AnnotationFn,
4195                                   llvm::Value *AnnotatedVal,
4196                                   StringRef AnnotationStr,
4197                                   SourceLocation Location);
4198 
4199   /// Emit local annotations for the local variable V, declared by D.
4200   void EmitVarAnnotations(const VarDecl *D, llvm::Value *V);
4201 
4202   /// Emit field annotations for the given field & value. Returns the
4203   /// annotation result.
4204   Address EmitFieldAnnotations(const FieldDecl *D, Address V);
4205 
4206   //===--------------------------------------------------------------------===//
4207   //                             Internal Helpers
4208   //===--------------------------------------------------------------------===//
4209 
4210   /// ContainsLabel - Return true if the statement contains a label in it.  If
4211   /// this statement is not executed normally, it not containing a label means
4212   /// that we can just remove the code.
4213   static bool ContainsLabel(const Stmt *S, bool IgnoreCaseStmts = false);
4214 
4215   /// containsBreak - Return true if the statement contains a break out of it.
4216   /// If the statement (recursively) contains a switch or loop with a break
4217   /// inside of it, this is fine.
4218   static bool containsBreak(const Stmt *S);
4219 
4220   /// Determine if the given statement might introduce a declaration into the
4221   /// current scope, by being a (possibly-labelled) DeclStmt.
4222   static bool mightAddDeclToScope(const Stmt *S);
4223 
4224   /// ConstantFoldsToSimpleInteger - If the specified expression does not fold
4225   /// to a constant, or if it does but contains a label, return false.  If it
4226   /// constant folds return true and set the boolean result in Result.
4227   bool ConstantFoldsToSimpleInteger(const Expr *Cond, bool &Result,
4228                                     bool AllowLabels = false);
4229 
4230   /// ConstantFoldsToSimpleInteger - If the specified expression does not fold
4231   /// to a constant, or if it does but contains a label, return false.  If it
4232   /// constant folds return true and set the folded value.
4233   bool ConstantFoldsToSimpleInteger(const Expr *Cond, llvm::APSInt &Result,
4234                                     bool AllowLabels = false);
4235 
4236   /// EmitBranchOnBoolExpr - Emit a branch on a boolean condition (e.g. for an
4237   /// if statement) to the specified blocks.  Based on the condition, this might
4238   /// try to simplify the codegen of the conditional based on the branch.
4239   /// TrueCount should be the number of times we expect the condition to
4240   /// evaluate to true based on PGO data.
4241   void EmitBranchOnBoolExpr(const Expr *Cond, llvm::BasicBlock *TrueBlock,
4242                             llvm::BasicBlock *FalseBlock, uint64_t TrueCount);
4243 
4244   /// Given an assignment `*LHS = RHS`, emit a test that checks if \p RHS is
4245   /// nonnull, if \p LHS is marked _Nonnull.
4246   void EmitNullabilityCheck(LValue LHS, llvm::Value *RHS, SourceLocation Loc);
4247 
4248   /// An enumeration which makes it easier to specify whether or not an
4249   /// operation is a subtraction.
4250   enum { NotSubtraction = false, IsSubtraction = true };
4251 
4252   /// Same as IRBuilder::CreateInBoundsGEP, but additionally emits a check to
4253   /// detect undefined behavior when the pointer overflow sanitizer is enabled.
4254   /// \p SignedIndices indicates whether any of the GEP indices are signed.
4255   /// \p IsSubtraction indicates whether the expression used to form the GEP
4256   /// is a subtraction.
4257   llvm::Value *EmitCheckedInBoundsGEP(llvm::Value *Ptr,
4258                                       ArrayRef<llvm::Value *> IdxList,
4259                                       bool SignedIndices,
4260                                       bool IsSubtraction,
4261                                       SourceLocation Loc,
4262                                       const Twine &Name = "");
4263 
4264   /// Specifies which type of sanitizer check to apply when handling a
4265   /// particular builtin.
4266   enum BuiltinCheckKind {
4267     BCK_CTZPassedZero,
4268     BCK_CLZPassedZero,
4269   };
4270 
4271   /// Emits an argument for a call to a builtin. If the builtin sanitizer is
4272   /// enabled, a runtime check specified by \p Kind is also emitted.
4273   llvm::Value *EmitCheckedArgForBuiltin(const Expr *E, BuiltinCheckKind Kind);
4274 
4275   /// Emit a description of a type in a format suitable for passing to
4276   /// a runtime sanitizer handler.
4277   llvm::Constant *EmitCheckTypeDescriptor(QualType T);
4278 
4279   /// Convert a value into a format suitable for passing to a runtime
4280   /// sanitizer handler.
4281   llvm::Value *EmitCheckValue(llvm::Value *V);
4282 
4283   /// Emit a description of a source location in a format suitable for
4284   /// passing to a runtime sanitizer handler.
4285   llvm::Constant *EmitCheckSourceLocation(SourceLocation Loc);
4286 
4287   /// Create a basic block that will either trap or call a handler function in
4288   /// the UBSan runtime with the provided arguments, and create a conditional
4289   /// branch to it.
4290   void EmitCheck(ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
4291                  SanitizerHandler Check, ArrayRef<llvm::Constant *> StaticArgs,
4292                  ArrayRef<llvm::Value *> DynamicArgs);
4293 
4294   /// Emit a slow path cross-DSO CFI check which calls __cfi_slowpath
4295   /// if Cond if false.
4296   void EmitCfiSlowPathCheck(SanitizerMask Kind, llvm::Value *Cond,
4297                             llvm::ConstantInt *TypeId, llvm::Value *Ptr,
4298                             ArrayRef<llvm::Constant *> StaticArgs);
4299 
4300   /// Emit a reached-unreachable diagnostic if \p Loc is valid and runtime
4301   /// checking is enabled. Otherwise, just emit an unreachable instruction.
4302   void EmitUnreachable(SourceLocation Loc);
4303 
4304   /// Create a basic block that will call the trap intrinsic, and emit a
4305   /// conditional branch to it, for the -ftrapv checks.
4306   void EmitTrapCheck(llvm::Value *Checked);
4307 
4308   /// Emit a call to trap or debugtrap and attach function attribute
4309   /// "trap-func-name" if specified.
4310   llvm::CallInst *EmitTrapCall(llvm::Intrinsic::ID IntrID);
4311 
4312   /// Emit a stub for the cross-DSO CFI check function.
4313   void EmitCfiCheckStub();
4314 
4315   /// Emit a cross-DSO CFI failure handling function.
4316   void EmitCfiCheckFail();
4317 
4318   /// Create a check for a function parameter that may potentially be
4319   /// declared as non-null.
4320   void EmitNonNullArgCheck(RValue RV, QualType ArgType, SourceLocation ArgLoc,
4321                            AbstractCallee AC, unsigned ParmNum);
4322 
4323   /// EmitCallArg - Emit a single call argument.
4324   void EmitCallArg(CallArgList &args, const Expr *E, QualType ArgType);
4325 
4326   /// EmitDelegateCallArg - We are performing a delegate call; that
4327   /// is, the current function is delegating to another one.  Produce
4328   /// a r-value suitable for passing the given parameter.
4329   void EmitDelegateCallArg(CallArgList &args, const VarDecl *param,
4330                            SourceLocation loc);
4331 
4332   /// SetFPAccuracy - Set the minimum required accuracy of the given floating
4333   /// point operation, expressed as the maximum relative error in ulp.
4334   void SetFPAccuracy(llvm::Value *Val, float Accuracy);
4335 
4336   /// SetFPModel - Control floating point behavior via fp-model settings.
4337   void SetFPModel();
4338 
4339 private:
4340   llvm::MDNode *getRangeForLoadFromType(QualType Ty);
4341   void EmitReturnOfRValue(RValue RV, QualType Ty);
4342 
4343   void deferPlaceholderReplacement(llvm::Instruction *Old, llvm::Value *New);
4344 
4345   llvm::SmallVector<std::pair<llvm::Instruction *, llvm::Value *>, 4>
4346   DeferredReplacements;
4347 
4348   /// Set the address of a local variable.
4349   void setAddrOfLocalVar(const VarDecl *VD, Address Addr) {
4350     assert(!LocalDeclMap.count(VD) && "Decl already exists in LocalDeclMap!");
4351     LocalDeclMap.insert({VD, Addr});
4352   }
4353 
4354   /// ExpandTypeFromArgs - Reconstruct a structure of type \arg Ty
4355   /// from function arguments into \arg Dst. See ABIArgInfo::Expand.
4356   ///
4357   /// \param AI - The first function argument of the expansion.
4358   void ExpandTypeFromArgs(QualType Ty, LValue Dst,
4359                           llvm::Function::arg_iterator &AI);
4360 
4361   /// ExpandTypeToArgs - Expand an CallArg \arg Arg, with the LLVM type for \arg
4362   /// Ty, into individual arguments on the provided vector \arg IRCallArgs,
4363   /// starting at index \arg IRCallArgPos. See ABIArgInfo::Expand.
4364   void ExpandTypeToArgs(QualType Ty, CallArg Arg, llvm::FunctionType *IRFuncTy,
4365                         SmallVectorImpl<llvm::Value *> &IRCallArgs,
4366                         unsigned &IRCallArgPos);
4367 
4368   llvm::Value* EmitAsmInput(const TargetInfo::ConstraintInfo &Info,
4369                             const Expr *InputExpr, std::string &ConstraintStr);
4370 
4371   llvm::Value* EmitAsmInputLValue(const TargetInfo::ConstraintInfo &Info,
4372                                   LValue InputValue, QualType InputType,
4373                                   std::string &ConstraintStr,
4374                                   SourceLocation Loc);
4375 
4376   /// Attempts to statically evaluate the object size of E. If that
4377   /// fails, emits code to figure the size of E out for us. This is
4378   /// pass_object_size aware.
4379   ///
4380   /// If EmittedExpr is non-null, this will use that instead of re-emitting E.
4381   llvm::Value *evaluateOrEmitBuiltinObjectSize(const Expr *E, unsigned Type,
4382                                                llvm::IntegerType *ResType,
4383                                                llvm::Value *EmittedE,
4384                                                bool IsDynamic);
4385 
4386   /// Emits the size of E, as required by __builtin_object_size. This
4387   /// function is aware of pass_object_size parameters, and will act accordingly
4388   /// if E is a parameter with the pass_object_size attribute.
4389   llvm::Value *emitBuiltinObjectSize(const Expr *E, unsigned Type,
4390                                      llvm::IntegerType *ResType,
4391                                      llvm::Value *EmittedE,
4392                                      bool IsDynamic);
4393 
4394   void emitZeroOrPatternForAutoVarInit(QualType type, const VarDecl &D,
4395                                        Address Loc);
4396 
4397 public:
4398 #ifndef NDEBUG
4399   // Determine whether the given argument is an Objective-C method
4400   // that may have type parameters in its signature.
4401   static bool isObjCMethodWithTypeParams(const ObjCMethodDecl *method) {
4402     const DeclContext *dc = method->getDeclContext();
4403     if (const ObjCInterfaceDecl *classDecl= dyn_cast<ObjCInterfaceDecl>(dc)) {
4404       return classDecl->getTypeParamListAsWritten();
4405     }
4406 
4407     if (const ObjCCategoryDecl *catDecl = dyn_cast<ObjCCategoryDecl>(dc)) {
4408       return catDecl->getTypeParamList();
4409     }
4410 
4411     return false;
4412   }
4413 
4414   template<typename T>
4415   static bool isObjCMethodWithTypeParams(const T *) { return false; }
4416 #endif
4417 
4418   enum class EvaluationOrder {
4419     ///! No language constraints on evaluation order.
4420     Default,
4421     ///! Language semantics require left-to-right evaluation.
4422     ForceLeftToRight,
4423     ///! Language semantics require right-to-left evaluation.
4424     ForceRightToLeft
4425   };
4426 
4427   /// EmitCallArgs - Emit call arguments for a function.
4428   template <typename T>
4429   void EmitCallArgs(CallArgList &Args, const T *CallArgTypeInfo,
4430                     llvm::iterator_range<CallExpr::const_arg_iterator> ArgRange,
4431                     AbstractCallee AC = AbstractCallee(),
4432                     unsigned ParamsToSkip = 0,
4433                     EvaluationOrder Order = EvaluationOrder::Default) {
4434     SmallVector<QualType, 16> ArgTypes;
4435     CallExpr::const_arg_iterator Arg = ArgRange.begin();
4436 
4437     assert((ParamsToSkip == 0 || CallArgTypeInfo) &&
4438            "Can't skip parameters if type info is not provided");
4439     if (CallArgTypeInfo) {
4440 #ifndef NDEBUG
4441       bool isGenericMethod = isObjCMethodWithTypeParams(CallArgTypeInfo);
4442 #endif
4443 
4444       // First, use the argument types that the type info knows about
4445       for (auto I = CallArgTypeInfo->param_type_begin() + ParamsToSkip,
4446                 E = CallArgTypeInfo->param_type_end();
4447            I != E; ++I, ++Arg) {
4448         assert(Arg != ArgRange.end() && "Running over edge of argument list!");
4449         assert((isGenericMethod ||
4450                 ((*I)->isVariablyModifiedType() ||
4451                  (*I).getNonReferenceType()->isObjCRetainableType() ||
4452                  getContext()
4453                          .getCanonicalType((*I).getNonReferenceType())
4454                          .getTypePtr() ==
4455                      getContext()
4456                          .getCanonicalType((*Arg)->getType())
4457                          .getTypePtr())) &&
4458                "type mismatch in call argument!");
4459         ArgTypes.push_back(*I);
4460       }
4461     }
4462 
4463     // Either we've emitted all the call args, or we have a call to variadic
4464     // function.
4465     assert((Arg == ArgRange.end() || !CallArgTypeInfo ||
4466             CallArgTypeInfo->isVariadic()) &&
4467            "Extra arguments in non-variadic function!");
4468 
4469     // If we still have any arguments, emit them using the type of the argument.
4470     for (auto *A : llvm::make_range(Arg, ArgRange.end()))
4471       ArgTypes.push_back(CallArgTypeInfo ? getVarArgType(A) : A->getType());
4472 
4473     EmitCallArgs(Args, ArgTypes, ArgRange, AC, ParamsToSkip, Order);
4474   }
4475 
4476   void EmitCallArgs(CallArgList &Args, ArrayRef<QualType> ArgTypes,
4477                     llvm::iterator_range<CallExpr::const_arg_iterator> ArgRange,
4478                     AbstractCallee AC = AbstractCallee(),
4479                     unsigned ParamsToSkip = 0,
4480                     EvaluationOrder Order = EvaluationOrder::Default);
4481 
4482   /// EmitPointerWithAlignment - Given an expression with a pointer type,
4483   /// emit the value and compute our best estimate of the alignment of the
4484   /// pointee.
4485   ///
4486   /// \param BaseInfo - If non-null, this will be initialized with
4487   /// information about the source of the alignment and the may-alias
4488   /// attribute.  Note that this function will conservatively fall back on
4489   /// the type when it doesn't recognize the expression and may-alias will
4490   /// be set to false.
4491   ///
4492   /// One reasonable way to use this information is when there's a language
4493   /// guarantee that the pointer must be aligned to some stricter value, and
4494   /// we're simply trying to ensure that sufficiently obvious uses of under-
4495   /// aligned objects don't get miscompiled; for example, a placement new
4496   /// into the address of a local variable.  In such a case, it's quite
4497   /// reasonable to just ignore the returned alignment when it isn't from an
4498   /// explicit source.
4499   Address EmitPointerWithAlignment(const Expr *Addr,
4500                                    LValueBaseInfo *BaseInfo = nullptr,
4501                                    TBAAAccessInfo *TBAAInfo = nullptr);
4502 
4503   /// If \p E references a parameter with pass_object_size info or a constant
4504   /// array size modifier, emit the object size divided by the size of \p EltTy.
4505   /// Otherwise return null.
4506   llvm::Value *LoadPassedObjectSize(const Expr *E, QualType EltTy);
4507 
4508   void EmitSanitizerStatReport(llvm::SanitizerStatKind SSK);
4509 
4510   struct MultiVersionResolverOption {
4511     llvm::Function *Function;
4512     FunctionDecl *FD;
4513     struct Conds {
4514       StringRef Architecture;
4515       llvm::SmallVector<StringRef, 8> Features;
4516 
4517       Conds(StringRef Arch, ArrayRef<StringRef> Feats)
4518           : Architecture(Arch), Features(Feats.begin(), Feats.end()) {}
4519     } Conditions;
4520 
4521     MultiVersionResolverOption(llvm::Function *F, StringRef Arch,
4522                                ArrayRef<StringRef> Feats)
4523         : Function(F), Conditions(Arch, Feats) {}
4524   };
4525 
4526   // Emits the body of a multiversion function's resolver. Assumes that the
4527   // options are already sorted in the proper order, with the 'default' option
4528   // last (if it exists).
4529   void EmitMultiVersionResolver(llvm::Function *Resolver,
4530                                 ArrayRef<MultiVersionResolverOption> Options);
4531 
4532   static uint64_t GetX86CpuSupportsMask(ArrayRef<StringRef> FeatureStrs);
4533 
4534 private:
4535   QualType getVarArgType(const Expr *Arg);
4536 
4537   void EmitDeclMetadata();
4538 
4539   BlockByrefHelpers *buildByrefHelpers(llvm::StructType &byrefType,
4540                                   const AutoVarEmission &emission);
4541 
4542   void AddObjCARCExceptionMetadata(llvm::Instruction *Inst);
4543 
4544   llvm::Value *GetValueForARMHint(unsigned BuiltinID);
4545   llvm::Value *EmitX86CpuIs(const CallExpr *E);
4546   llvm::Value *EmitX86CpuIs(StringRef CPUStr);
4547   llvm::Value *EmitX86CpuSupports(const CallExpr *E);
4548   llvm::Value *EmitX86CpuSupports(ArrayRef<StringRef> FeatureStrs);
4549   llvm::Value *EmitX86CpuSupports(uint64_t Mask);
4550   llvm::Value *EmitX86CpuInit();
4551   llvm::Value *FormResolverCondition(const MultiVersionResolverOption &RO);
4552 };
4553 
4554 inline DominatingLLVMValue::saved_type
4555 DominatingLLVMValue::save(CodeGenFunction &CGF, llvm::Value *value) {
4556   if (!needsSaving(value)) return saved_type(value, false);
4557 
4558   // Otherwise, we need an alloca.
4559   auto align = CharUnits::fromQuantity(
4560             CGF.CGM.getDataLayout().getPrefTypeAlignment(value->getType()));
4561   Address alloca =
4562     CGF.CreateTempAlloca(value->getType(), align, "cond-cleanup.save");
4563   CGF.Builder.CreateStore(value, alloca);
4564 
4565   return saved_type(alloca.getPointer(), true);
4566 }
4567 
4568 inline llvm::Value *DominatingLLVMValue::restore(CodeGenFunction &CGF,
4569                                                  saved_type value) {
4570   // If the value says it wasn't saved, trust that it's still dominating.
4571   if (!value.getInt()) return value.getPointer();
4572 
4573   // Otherwise, it should be an alloca instruction, as set up in save().
4574   auto alloca = cast<llvm::AllocaInst>(value.getPointer());
4575   return CGF.Builder.CreateAlignedLoad(alloca, alloca->getAlign());
4576 }
4577 
4578 }  // end namespace CodeGen
4579 
4580 // Map the LangOption for floating point exception behavior into
4581 // the corresponding enum in the IR.
4582 llvm::fp::ExceptionBehavior
4583 ToConstrainedExceptMD(LangOptions::FPExceptionModeKind Kind);
4584 }  // end namespace clang
4585 
4586 #endif
4587