xref: /freebsd/contrib/llvm-project/clang/lib/CodeGen/CodeGenFunction.h (revision 02e9120893770924227138ba49df1edb3896112a)
1 //===-- CodeGenFunction.h - Per-Function state for LLVM CodeGen -*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This is the internal per-function state used for llvm translation.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_LIB_CODEGEN_CODEGENFUNCTION_H
14 #define LLVM_CLANG_LIB_CODEGEN_CODEGENFUNCTION_H
15 
16 #include "CGBuilder.h"
17 #include "CGDebugInfo.h"
18 #include "CGLoopInfo.h"
19 #include "CGValue.h"
20 #include "CodeGenModule.h"
21 #include "CodeGenPGO.h"
22 #include "EHScopeStack.h"
23 #include "VarBypassDetector.h"
24 #include "clang/AST/CharUnits.h"
25 #include "clang/AST/CurrentSourceLocExprScope.h"
26 #include "clang/AST/ExprCXX.h"
27 #include "clang/AST/ExprObjC.h"
28 #include "clang/AST/ExprOpenMP.h"
29 #include "clang/AST/StmtOpenMP.h"
30 #include "clang/AST/Type.h"
31 #include "clang/Basic/ABI.h"
32 #include "clang/Basic/CapturedStmt.h"
33 #include "clang/Basic/CodeGenOptions.h"
34 #include "clang/Basic/OpenMPKinds.h"
35 #include "clang/Basic/TargetInfo.h"
36 #include "llvm/ADT/ArrayRef.h"
37 #include "llvm/ADT/DenseMap.h"
38 #include "llvm/ADT/MapVector.h"
39 #include "llvm/ADT/SmallVector.h"
40 #include "llvm/Frontend/OpenMP/OMPIRBuilder.h"
41 #include "llvm/IR/ValueHandle.h"
42 #include "llvm/Support/Debug.h"
43 #include "llvm/Transforms/Utils/SanitizerStats.h"
44 #include <optional>
45 
46 namespace llvm {
47 class BasicBlock;
48 class LLVMContext;
49 class MDNode;
50 class SwitchInst;
51 class Twine;
52 class Value;
53 class CanonicalLoopInfo;
54 }
55 
56 namespace clang {
57 class ASTContext;
58 class CXXDestructorDecl;
59 class CXXForRangeStmt;
60 class CXXTryStmt;
61 class Decl;
62 class LabelDecl;
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 OMPUseDevicePtrClause;
80 class OMPUseDeviceAddrClause;
81 class SVETypeFlags;
82 class OMPExecutableDirective;
83 
84 namespace analyze_os_log {
85 class OSLogBufferLayout;
86 }
87 
88 namespace CodeGen {
89 class CodeGenTypes;
90 class CGCallee;
91 class CGFunctionInfo;
92 class CGBlockInfo;
93 class CGCXXABI;
94 class BlockByrefHelpers;
95 class BlockByrefInfo;
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, 0)             \
121   SANITIZER_CHECK(ImplicitConversion, implicit_conversion, 0)                  \
122   SANITIZER_CHECK(InvalidBuiltin, invalid_builtin, 0)                          \
123   SANITIZER_CHECK(InvalidObjCCast, invalid_objc_cast, 0)                       \
124   SANITIZER_CHECK(LoadInvalidValue, load_invalid_value, 0)                     \
125   SANITIZER_CHECK(MissingReturn, missing_return, 0)                            \
126   SANITIZER_CHECK(MulOverflow, mul_overflow, 0)                                \
127   SANITIZER_CHECK(NegateOverflow, negate_overflow, 0)                          \
128   SANITIZER_CHECK(NullabilityArg, nullability_arg, 0)                          \
129   SANITIZER_CHECK(NullabilityReturn, nullability_return, 1)                    \
130   SANITIZER_CHECK(NonnullArg, nonnull_arg, 0)                                  \
131   SANITIZER_CHECK(NonnullReturn, nonnull_return, 1)                            \
132   SANITIZER_CHECK(OutOfBounds, out_of_bounds, 0)                               \
133   SANITIZER_CHECK(PointerOverflow, pointer_overflow, 0)                        \
134   SANITIZER_CHECK(ShiftOutOfBounds, shift_out_of_bounds, 0)                    \
135   SANITIZER_CHECK(SubOverflow, sub_overflow, 0)                                \
136   SANITIZER_CHECK(TypeMismatch, type_mismatch, 1)                              \
137   SANITIZER_CHECK(AlignmentAssumption, alignment_assumption, 0)                \
138   SANITIZER_CHECK(VLABoundNotPositive, vla_bound_not_positive, 0)
139 
140 enum SanitizerHandler {
141 #define SANITIZER_CHECK(Enum, Name, Version) Enum,
142   LIST_SANITIZER_CHECKS
143 #undef SANITIZER_CHECK
144 };
145 
146 /// Helper class with most of the code for saving a value for a
147 /// conditional expression cleanup.
148 struct DominatingLLVMValue {
149   typedef llvm::PointerIntPair<llvm::Value*, 1, bool> saved_type;
150 
151   /// Answer whether the given value needs extra work to be saved.
152   static bool needsSaving(llvm::Value *value) {
153     // If it's not an instruction, we don't need to save.
154     if (!isa<llvm::Instruction>(value)) return false;
155 
156     // If it's an instruction in the entry block, we don't need to save.
157     llvm::BasicBlock *block = cast<llvm::Instruction>(value)->getParent();
158     return (block != &block->getParent()->getEntryBlock());
159   }
160 
161   static saved_type save(CodeGenFunction &CGF, llvm::Value *value);
162   static llvm::Value *restore(CodeGenFunction &CGF, saved_type value);
163 };
164 
165 /// A partial specialization of DominatingValue for llvm::Values that
166 /// might be llvm::Instructions.
167 template <class T> struct DominatingPointer<T,true> : DominatingLLVMValue {
168   typedef T *type;
169   static type restore(CodeGenFunction &CGF, saved_type value) {
170     return static_cast<T*>(DominatingLLVMValue::restore(CGF, value));
171   }
172 };
173 
174 /// A specialization of DominatingValue for Address.
175 template <> struct DominatingValue<Address> {
176   typedef Address type;
177 
178   struct saved_type {
179     DominatingLLVMValue::saved_type SavedValue;
180     llvm::Type *ElementType;
181     CharUnits Alignment;
182   };
183 
184   static bool needsSaving(type value) {
185     return DominatingLLVMValue::needsSaving(value.getPointer());
186   }
187   static saved_type save(CodeGenFunction &CGF, type value) {
188     return { DominatingLLVMValue::save(CGF, value.getPointer()),
189              value.getElementType(), value.getAlignment() };
190   }
191   static type restore(CodeGenFunction &CGF, saved_type value) {
192     return Address(DominatingLLVMValue::restore(CGF, value.SavedValue),
193                    value.ElementType, value.Alignment);
194   }
195 };
196 
197 /// A specialization of DominatingValue for RValue.
198 template <> struct DominatingValue<RValue> {
199   typedef RValue type;
200   class saved_type {
201     enum Kind { ScalarLiteral, ScalarAddress, AggregateLiteral,
202                 AggregateAddress, ComplexAddress };
203 
204     llvm::Value *Value;
205     llvm::Type *ElementType;
206     unsigned K : 3;
207     unsigned Align : 29;
208     saved_type(llvm::Value *v, llvm::Type *e, Kind k, unsigned a = 0)
209       : Value(v), ElementType(e), K(k), Align(a) {}
210 
211   public:
212     static bool needsSaving(RValue value);
213     static saved_type save(CodeGenFunction &CGF, RValue value);
214     RValue restore(CodeGenFunction &CGF);
215 
216     // implementations in CGCleanup.cpp
217   };
218 
219   static bool needsSaving(type value) {
220     return saved_type::needsSaving(value);
221   }
222   static saved_type save(CodeGenFunction &CGF, type value) {
223     return saved_type::save(CGF, value);
224   }
225   static type restore(CodeGenFunction &CGF, saved_type value) {
226     return value.restore(CGF);
227   }
228 };
229 
230 /// CodeGenFunction - This class organizes the per-function state that is used
231 /// while generating LLVM code.
232 class CodeGenFunction : public CodeGenTypeCache {
233   CodeGenFunction(const CodeGenFunction &) = delete;
234   void operator=(const CodeGenFunction &) = delete;
235 
236   friend class CGCXXABI;
237 public:
238   /// A jump destination is an abstract label, branching to which may
239   /// require a jump out through normal cleanups.
240   struct JumpDest {
241     JumpDest() : Block(nullptr), Index(0) {}
242     JumpDest(llvm::BasicBlock *Block, EHScopeStack::stable_iterator Depth,
243              unsigned Index)
244         : Block(Block), ScopeDepth(Depth), Index(Index) {}
245 
246     bool isValid() const { return Block != nullptr; }
247     llvm::BasicBlock *getBlock() const { return Block; }
248     EHScopeStack::stable_iterator getScopeDepth() const { return ScopeDepth; }
249     unsigned getDestIndex() const { return Index; }
250 
251     // This should be used cautiously.
252     void setScopeDepth(EHScopeStack::stable_iterator depth) {
253       ScopeDepth = depth;
254     }
255 
256   private:
257     llvm::BasicBlock *Block;
258     EHScopeStack::stable_iterator ScopeDepth;
259     unsigned Index;
260   };
261 
262   CodeGenModule &CGM;  // Per-module state.
263   const TargetInfo &Target;
264 
265   // For EH/SEH outlined funclets, this field points to parent's CGF
266   CodeGenFunction *ParentCGF = nullptr;
267 
268   typedef std::pair<llvm::Value *, llvm::Value *> ComplexPairTy;
269   LoopInfoStack LoopStack;
270   CGBuilderTy Builder;
271 
272   // Stores variables for which we can't generate correct lifetime markers
273   // because of jumps.
274   VarBypassDetector Bypasses;
275 
276   /// List of recently emitted OMPCanonicalLoops.
277   ///
278   /// Since OMPCanonicalLoops are nested inside other statements (in particular
279   /// CapturedStmt generated by OMPExecutableDirective and non-perfectly nested
280   /// loops), we cannot directly call OMPEmitOMPCanonicalLoop and receive its
281   /// llvm::CanonicalLoopInfo. Instead, we call EmitStmt and any
282   /// OMPEmitOMPCanonicalLoop called by it will add its CanonicalLoopInfo to
283   /// this stack when done. Entering a new loop requires clearing this list; it
284   /// either means we start parsing a new loop nest (in which case the previous
285   /// loop nest goes out of scope) or a second loop in the same level in which
286   /// case it would be ambiguous into which of the two (or more) loops the loop
287   /// nest would extend.
288   SmallVector<llvm::CanonicalLoopInfo *, 4> OMPLoopNestStack;
289 
290   /// Number of nested loop to be consumed by the last surrounding
291   /// loop-associated directive.
292   int ExpectedOMPLoopDepth = 0;
293 
294   // CodeGen lambda for loops and support for ordered clause
295   typedef llvm::function_ref<void(CodeGenFunction &, const OMPLoopDirective &,
296                                   JumpDest)>
297       CodeGenLoopTy;
298   typedef llvm::function_ref<void(CodeGenFunction &, SourceLocation,
299                                   const unsigned, const bool)>
300       CodeGenOrderedTy;
301 
302   // Codegen lambda for loop bounds in worksharing loop constructs
303   typedef llvm::function_ref<std::pair<LValue, LValue>(
304       CodeGenFunction &, const OMPExecutableDirective &S)>
305       CodeGenLoopBoundsTy;
306 
307   // Codegen lambda for loop bounds in dispatch-based loop implementation
308   typedef llvm::function_ref<std::pair<llvm::Value *, llvm::Value *>(
309       CodeGenFunction &, const OMPExecutableDirective &S, Address LB,
310       Address UB)>
311       CodeGenDispatchBoundsTy;
312 
313   /// CGBuilder insert helper. This function is called after an
314   /// instruction is created using Builder.
315   void InsertHelper(llvm::Instruction *I, const llvm::Twine &Name,
316                     llvm::BasicBlock *BB,
317                     llvm::BasicBlock::iterator InsertPt) const;
318 
319   /// CurFuncDecl - Holds the Decl for the current outermost
320   /// non-closure context.
321   const Decl *CurFuncDecl = nullptr;
322   /// CurCodeDecl - This is the inner-most code context, which includes blocks.
323   const Decl *CurCodeDecl = nullptr;
324   const CGFunctionInfo *CurFnInfo = nullptr;
325   QualType FnRetTy;
326   llvm::Function *CurFn = nullptr;
327 
328   /// Save Parameter Decl for coroutine.
329   llvm::SmallVector<const ParmVarDecl *, 4> FnArgs;
330 
331   // Holds coroutine data if the current function is a coroutine. We use a
332   // wrapper to manage its lifetime, so that we don't have to define CGCoroData
333   // in this header.
334   struct CGCoroInfo {
335     std::unique_ptr<CGCoroData> Data;
336     bool InSuspendBlock = false;
337     CGCoroInfo();
338     ~CGCoroInfo();
339   };
340   CGCoroInfo CurCoro;
341 
342   bool isCoroutine() const {
343     return CurCoro.Data != nullptr;
344   }
345 
346   bool inSuspendBlock() const {
347     return isCoroutine() && CurCoro.InSuspendBlock;
348   }
349 
350   /// CurGD - The GlobalDecl for the current function being compiled.
351   GlobalDecl CurGD;
352 
353   /// PrologueCleanupDepth - The cleanup depth enclosing all the
354   /// cleanups associated with the parameters.
355   EHScopeStack::stable_iterator PrologueCleanupDepth;
356 
357   /// ReturnBlock - Unified return block.
358   JumpDest ReturnBlock;
359 
360   /// ReturnValue - The temporary alloca to hold the return
361   /// value. This is invalid iff the function has no return value.
362   Address ReturnValue = Address::invalid();
363 
364   /// ReturnValuePointer - The temporary alloca to hold a pointer to sret.
365   /// This is invalid if sret is not in use.
366   Address ReturnValuePointer = Address::invalid();
367 
368   /// If a return statement is being visited, this holds the return statment's
369   /// result expression.
370   const Expr *RetExpr = nullptr;
371 
372   /// Return true if a label was seen in the current scope.
373   bool hasLabelBeenSeenInCurrentScope() const {
374     if (CurLexicalScope)
375       return CurLexicalScope->hasLabels();
376     return !LabelMap.empty();
377   }
378 
379   /// AllocaInsertPoint - This is an instruction in the entry block before which
380   /// we prefer to insert allocas.
381   llvm::AssertingVH<llvm::Instruction> AllocaInsertPt;
382 
383 private:
384   /// PostAllocaInsertPt - This is a place in the prologue where code can be
385   /// inserted that will be dominated by all the static allocas. This helps
386   /// achieve two things:
387   ///   1. Contiguity of all static allocas (within the prologue) is maintained.
388   ///   2. All other prologue code (which are dominated by static allocas) do
389   ///      appear in the source order immediately after all static allocas.
390   ///
391   /// PostAllocaInsertPt will be lazily created when it is *really* required.
392   llvm::AssertingVH<llvm::Instruction> PostAllocaInsertPt = nullptr;
393 
394 public:
395   /// Return PostAllocaInsertPt. If it is not yet created, then insert it
396   /// immediately after AllocaInsertPt.
397   llvm::Instruction *getPostAllocaInsertPoint() {
398     if (!PostAllocaInsertPt) {
399       assert(AllocaInsertPt &&
400              "Expected static alloca insertion point at function prologue");
401       assert(AllocaInsertPt->getParent()->isEntryBlock() &&
402              "EBB should be entry block of the current code gen function");
403       PostAllocaInsertPt = AllocaInsertPt->clone();
404       PostAllocaInsertPt->setName("postallocapt");
405       PostAllocaInsertPt->insertAfter(AllocaInsertPt);
406     }
407 
408     return PostAllocaInsertPt;
409   }
410 
411   /// API for captured statement code generation.
412   class CGCapturedStmtInfo {
413   public:
414     explicit CGCapturedStmtInfo(CapturedRegionKind K = CR_Default)
415         : Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {}
416     explicit CGCapturedStmtInfo(const CapturedStmt &S,
417                                 CapturedRegionKind K = CR_Default)
418       : Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {
419 
420       RecordDecl::field_iterator Field =
421         S.getCapturedRecordDecl()->field_begin();
422       for (CapturedStmt::const_capture_iterator I = S.capture_begin(),
423                                                 E = S.capture_end();
424            I != E; ++I, ++Field) {
425         if (I->capturesThis())
426           CXXThisFieldDecl = *Field;
427         else if (I->capturesVariable())
428           CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
429         else if (I->capturesVariableByCopy())
430           CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
431       }
432     }
433 
434     virtual ~CGCapturedStmtInfo();
435 
436     CapturedRegionKind getKind() const { return Kind; }
437 
438     virtual void setContextValue(llvm::Value *V) { ThisValue = V; }
439     // Retrieve the value of the context parameter.
440     virtual llvm::Value *getContextValue() const { return ThisValue; }
441 
442     /// Lookup the captured field decl for a variable.
443     virtual const FieldDecl *lookup(const VarDecl *VD) const {
444       return CaptureFields.lookup(VD->getCanonicalDecl());
445     }
446 
447     bool isCXXThisExprCaptured() const { return getThisFieldDecl() != nullptr; }
448     virtual FieldDecl *getThisFieldDecl() const { return CXXThisFieldDecl; }
449 
450     static bool classof(const CGCapturedStmtInfo *) {
451       return true;
452     }
453 
454     /// Emit the captured statement body.
455     virtual void EmitBody(CodeGenFunction &CGF, const Stmt *S) {
456       CGF.incrementProfileCounter(S);
457       CGF.EmitStmt(S);
458     }
459 
460     /// Get the name of the capture helper.
461     virtual StringRef getHelperName() const { return "__captured_stmt"; }
462 
463     /// Get the CaptureFields
464     llvm::SmallDenseMap<const VarDecl *, FieldDecl *> getCaptureFields() {
465       return CaptureFields;
466     }
467 
468   private:
469     /// The kind of captured statement being generated.
470     CapturedRegionKind Kind;
471 
472     /// Keep the map between VarDecl and FieldDecl.
473     llvm::SmallDenseMap<const VarDecl *, FieldDecl *> CaptureFields;
474 
475     /// The base address of the captured record, passed in as the first
476     /// argument of the parallel region function.
477     llvm::Value *ThisValue;
478 
479     /// Captured 'this' type.
480     FieldDecl *CXXThisFieldDecl;
481   };
482   CGCapturedStmtInfo *CapturedStmtInfo = nullptr;
483 
484   /// RAII for correct setting/restoring of CapturedStmtInfo.
485   class CGCapturedStmtRAII {
486   private:
487     CodeGenFunction &CGF;
488     CGCapturedStmtInfo *PrevCapturedStmtInfo;
489   public:
490     CGCapturedStmtRAII(CodeGenFunction &CGF,
491                        CGCapturedStmtInfo *NewCapturedStmtInfo)
492         : CGF(CGF), PrevCapturedStmtInfo(CGF.CapturedStmtInfo) {
493       CGF.CapturedStmtInfo = NewCapturedStmtInfo;
494     }
495     ~CGCapturedStmtRAII() { CGF.CapturedStmtInfo = PrevCapturedStmtInfo; }
496   };
497 
498   /// An abstract representation of regular/ObjC call/message targets.
499   class AbstractCallee {
500     /// The function declaration of the callee.
501     const Decl *CalleeDecl;
502 
503   public:
504     AbstractCallee() : CalleeDecl(nullptr) {}
505     AbstractCallee(const FunctionDecl *FD) : CalleeDecl(FD) {}
506     AbstractCallee(const ObjCMethodDecl *OMD) : CalleeDecl(OMD) {}
507     bool hasFunctionDecl() const {
508       return isa_and_nonnull<FunctionDecl>(CalleeDecl);
509     }
510     const Decl *getDecl() const { return CalleeDecl; }
511     unsigned getNumParams() const {
512       if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
513         return FD->getNumParams();
514       return cast<ObjCMethodDecl>(CalleeDecl)->param_size();
515     }
516     const ParmVarDecl *getParamDecl(unsigned I) const {
517       if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
518         return FD->getParamDecl(I);
519       return *(cast<ObjCMethodDecl>(CalleeDecl)->param_begin() + I);
520     }
521   };
522 
523   /// Sanitizers enabled for this function.
524   SanitizerSet SanOpts;
525 
526   /// True if CodeGen currently emits code implementing sanitizer checks.
527   bool IsSanitizerScope = false;
528 
529   /// RAII object to set/unset CodeGenFunction::IsSanitizerScope.
530   class SanitizerScope {
531     CodeGenFunction *CGF;
532   public:
533     SanitizerScope(CodeGenFunction *CGF);
534     ~SanitizerScope();
535   };
536 
537   /// In C++, whether we are code generating a thunk.  This controls whether we
538   /// should emit cleanups.
539   bool CurFuncIsThunk = false;
540 
541   /// In ARC, whether we should autorelease the return value.
542   bool AutoreleaseResult = false;
543 
544   /// Whether we processed a Microsoft-style asm block during CodeGen. These can
545   /// potentially set the return value.
546   bool SawAsmBlock = false;
547 
548   GlobalDecl CurSEHParent;
549 
550   /// True if the current function is an outlined SEH helper. This can be a
551   /// finally block or filter expression.
552   bool IsOutlinedSEHHelper = false;
553 
554   /// True if CodeGen currently emits code inside presereved access index
555   /// region.
556   bool IsInPreservedAIRegion = false;
557 
558   /// True if the current statement has nomerge attribute.
559   bool InNoMergeAttributedStmt = false;
560 
561   /// True if the current statement has noinline attribute.
562   bool InNoInlineAttributedStmt = false;
563 
564   /// True if the current statement has always_inline attribute.
565   bool InAlwaysInlineAttributedStmt = false;
566 
567   // The CallExpr within the current statement that the musttail attribute
568   // applies to.  nullptr if there is no 'musttail' on the current statement.
569   const CallExpr *MustTailCall = nullptr;
570 
571   /// Returns true if a function must make progress, which means the
572   /// mustprogress attribute can be added.
573   bool checkIfFunctionMustProgress() {
574     if (CGM.getCodeGenOpts().getFiniteLoops() ==
575         CodeGenOptions::FiniteLoopsKind::Never)
576       return false;
577 
578     // C++11 and later guarantees that a thread eventually will do one of the
579     // following (C++11 [intro.multithread]p24 and C++17 [intro.progress]p1):
580     // - terminate,
581     //  - make a call to a library I/O function,
582     //  - perform an access through a volatile glvalue, or
583     //  - perform a synchronization operation or an atomic operation.
584     //
585     // Hence each function is 'mustprogress' in C++11 or later.
586     return getLangOpts().CPlusPlus11;
587   }
588 
589   /// Returns true if a loop must make progress, which means the mustprogress
590   /// attribute can be added. \p HasConstantCond indicates whether the branch
591   /// condition is a known constant.
592   bool checkIfLoopMustProgress(bool HasConstantCond) {
593     if (CGM.getCodeGenOpts().getFiniteLoops() ==
594         CodeGenOptions::FiniteLoopsKind::Always)
595       return true;
596     if (CGM.getCodeGenOpts().getFiniteLoops() ==
597         CodeGenOptions::FiniteLoopsKind::Never)
598       return false;
599 
600     // If the containing function must make progress, loops also must make
601     // progress (as in C++11 and later).
602     if (checkIfFunctionMustProgress())
603       return true;
604 
605     // Now apply rules for plain C (see  6.8.5.6 in C11).
606     // Loops with constant conditions do not have to make progress in any C
607     // version.
608     if (HasConstantCond)
609       return false;
610 
611     // Loops with non-constant conditions must make progress in C11 and later.
612     return getLangOpts().C11;
613   }
614 
615   const CodeGen::CGBlockInfo *BlockInfo = nullptr;
616   llvm::Value *BlockPointer = nullptr;
617 
618   llvm::DenseMap<const ValueDecl *, FieldDecl *> LambdaCaptureFields;
619   FieldDecl *LambdaThisCaptureField = nullptr;
620 
621   /// A mapping from NRVO variables to the flags used to indicate
622   /// when the NRVO has been applied to this variable.
623   llvm::DenseMap<const VarDecl *, llvm::Value *> NRVOFlags;
624 
625   EHScopeStack EHStack;
626   llvm::SmallVector<char, 256> LifetimeExtendedCleanupStack;
627   llvm::SmallVector<const JumpDest *, 2> SEHTryEpilogueStack;
628 
629   llvm::Instruction *CurrentFuncletPad = nullptr;
630 
631   class CallLifetimeEnd final : public EHScopeStack::Cleanup {
632     bool isRedundantBeforeReturn() override { return true; }
633 
634     llvm::Value *Addr;
635     llvm::Value *Size;
636 
637   public:
638     CallLifetimeEnd(Address addr, llvm::Value *size)
639         : Addr(addr.getPointer()), Size(size) {}
640 
641     void Emit(CodeGenFunction &CGF, Flags flags) override {
642       CGF.EmitLifetimeEnd(Size, Addr);
643     }
644   };
645 
646   /// Header for data within LifetimeExtendedCleanupStack.
647   struct LifetimeExtendedCleanupHeader {
648     /// The size of the following cleanup object.
649     unsigned Size;
650     /// The kind of cleanup to push: a value from the CleanupKind enumeration.
651     unsigned Kind : 31;
652     /// Whether this is a conditional cleanup.
653     unsigned IsConditional : 1;
654 
655     size_t getSize() const { return Size; }
656     CleanupKind getKind() const { return (CleanupKind)Kind; }
657     bool isConditional() const { return IsConditional; }
658   };
659 
660   /// i32s containing the indexes of the cleanup destinations.
661   Address NormalCleanupDest = Address::invalid();
662 
663   unsigned NextCleanupDestIndex = 1;
664 
665   /// EHResumeBlock - Unified block containing a call to llvm.eh.resume.
666   llvm::BasicBlock *EHResumeBlock = nullptr;
667 
668   /// The exception slot.  All landing pads write the current exception pointer
669   /// into this alloca.
670   llvm::Value *ExceptionSlot = nullptr;
671 
672   /// The selector slot.  Under the MandatoryCleanup model, all landing pads
673   /// write the current selector value into this alloca.
674   llvm::AllocaInst *EHSelectorSlot = nullptr;
675 
676   /// A stack of exception code slots. Entering an __except block pushes a slot
677   /// on the stack and leaving pops one. The __exception_code() intrinsic loads
678   /// a value from the top of the stack.
679   SmallVector<Address, 1> SEHCodeSlotStack;
680 
681   /// Value returned by __exception_info intrinsic.
682   llvm::Value *SEHInfo = nullptr;
683 
684   /// Emits a landing pad for the current EH stack.
685   llvm::BasicBlock *EmitLandingPad();
686 
687   llvm::BasicBlock *getInvokeDestImpl();
688 
689   /// Parent loop-based directive for scan directive.
690   const OMPExecutableDirective *OMPParentLoopDirectiveForScan = nullptr;
691   llvm::BasicBlock *OMPBeforeScanBlock = nullptr;
692   llvm::BasicBlock *OMPAfterScanBlock = nullptr;
693   llvm::BasicBlock *OMPScanExitBlock = nullptr;
694   llvm::BasicBlock *OMPScanDispatch = nullptr;
695   bool OMPFirstScanLoop = false;
696 
697   /// Manages parent directive for scan directives.
698   class ParentLoopDirectiveForScanRegion {
699     CodeGenFunction &CGF;
700     const OMPExecutableDirective *ParentLoopDirectiveForScan;
701 
702   public:
703     ParentLoopDirectiveForScanRegion(
704         CodeGenFunction &CGF,
705         const OMPExecutableDirective &ParentLoopDirectiveForScan)
706         : CGF(CGF),
707           ParentLoopDirectiveForScan(CGF.OMPParentLoopDirectiveForScan) {
708       CGF.OMPParentLoopDirectiveForScan = &ParentLoopDirectiveForScan;
709     }
710     ~ParentLoopDirectiveForScanRegion() {
711       CGF.OMPParentLoopDirectiveForScan = ParentLoopDirectiveForScan;
712     }
713   };
714 
715   template <class T>
716   typename DominatingValue<T>::saved_type saveValueInCond(T value) {
717     return DominatingValue<T>::save(*this, value);
718   }
719 
720   class CGFPOptionsRAII {
721   public:
722     CGFPOptionsRAII(CodeGenFunction &CGF, FPOptions FPFeatures);
723     CGFPOptionsRAII(CodeGenFunction &CGF, const Expr *E);
724     ~CGFPOptionsRAII();
725 
726   private:
727     void ConstructorHelper(FPOptions FPFeatures);
728     CodeGenFunction &CGF;
729     FPOptions OldFPFeatures;
730     llvm::fp::ExceptionBehavior OldExcept;
731     llvm::RoundingMode OldRounding;
732     std::optional<CGBuilderTy::FastMathFlagGuard> FMFGuard;
733   };
734   FPOptions CurFPFeatures;
735 
736 public:
737   /// ObjCEHValueStack - Stack of Objective-C exception values, used for
738   /// rethrows.
739   SmallVector<llvm::Value*, 8> ObjCEHValueStack;
740 
741   /// A class controlling the emission of a finally block.
742   class FinallyInfo {
743     /// Where the catchall's edge through the cleanup should go.
744     JumpDest RethrowDest;
745 
746     /// A function to call to enter the catch.
747     llvm::FunctionCallee BeginCatchFn;
748 
749     /// An i1 variable indicating whether or not the @finally is
750     /// running for an exception.
751     llvm::AllocaInst *ForEHVar = nullptr;
752 
753     /// An i8* variable into which the exception pointer to rethrow
754     /// has been saved.
755     llvm::AllocaInst *SavedExnVar = nullptr;
756 
757   public:
758     void enter(CodeGenFunction &CGF, const Stmt *Finally,
759                llvm::FunctionCallee beginCatchFn,
760                llvm::FunctionCallee endCatchFn, llvm::FunctionCallee rethrowFn);
761     void exit(CodeGenFunction &CGF);
762   };
763 
764   /// Returns true inside SEH __try blocks.
765   bool isSEHTryScope() const { return !SEHTryEpilogueStack.empty(); }
766 
767   /// Returns true while emitting a cleanuppad.
768   bool isCleanupPadScope() const {
769     return CurrentFuncletPad && isa<llvm::CleanupPadInst>(CurrentFuncletPad);
770   }
771 
772   /// pushFullExprCleanup - Push a cleanup to be run at the end of the
773   /// current full-expression.  Safe against the possibility that
774   /// we're currently inside a conditionally-evaluated expression.
775   template <class T, class... As>
776   void pushFullExprCleanup(CleanupKind kind, As... A) {
777     // If we're not in a conditional branch, or if none of the
778     // arguments requires saving, then use the unconditional cleanup.
779     if (!isInConditionalBranch())
780       return EHStack.pushCleanup<T>(kind, A...);
781 
782     // Stash values in a tuple so we can guarantee the order of saves.
783     typedef std::tuple<typename DominatingValue<As>::saved_type...> SavedTuple;
784     SavedTuple Saved{saveValueInCond(A)...};
785 
786     typedef EHScopeStack::ConditionalCleanup<T, As...> CleanupType;
787     EHStack.pushCleanupTuple<CleanupType>(kind, Saved);
788     initFullExprCleanup();
789   }
790 
791   /// Queue a cleanup to be pushed after finishing the current full-expression,
792   /// potentially with an active flag.
793   template <class T, class... As>
794   void pushCleanupAfterFullExpr(CleanupKind Kind, As... A) {
795     if (!isInConditionalBranch())
796       return pushCleanupAfterFullExprWithActiveFlag<T>(Kind, Address::invalid(),
797                                                        A...);
798 
799     Address ActiveFlag = createCleanupActiveFlag();
800     assert(!DominatingValue<Address>::needsSaving(ActiveFlag) &&
801            "cleanup active flag should never need saving");
802 
803     typedef std::tuple<typename DominatingValue<As>::saved_type...> SavedTuple;
804     SavedTuple Saved{saveValueInCond(A)...};
805 
806     typedef EHScopeStack::ConditionalCleanup<T, As...> CleanupType;
807     pushCleanupAfterFullExprWithActiveFlag<CleanupType>(Kind, ActiveFlag, Saved);
808   }
809 
810   template <class T, class... As>
811   void pushCleanupAfterFullExprWithActiveFlag(CleanupKind Kind,
812                                               Address ActiveFlag, As... A) {
813     LifetimeExtendedCleanupHeader Header = {sizeof(T), Kind,
814                                             ActiveFlag.isValid()};
815 
816     size_t OldSize = LifetimeExtendedCleanupStack.size();
817     LifetimeExtendedCleanupStack.resize(
818         LifetimeExtendedCleanupStack.size() + sizeof(Header) + Header.Size +
819         (Header.IsConditional ? sizeof(ActiveFlag) : 0));
820 
821     static_assert(sizeof(Header) % alignof(T) == 0,
822                   "Cleanup will be allocated on misaligned address");
823     char *Buffer = &LifetimeExtendedCleanupStack[OldSize];
824     new (Buffer) LifetimeExtendedCleanupHeader(Header);
825     new (Buffer + sizeof(Header)) T(A...);
826     if (Header.IsConditional)
827       new (Buffer + sizeof(Header) + sizeof(T)) Address(ActiveFlag);
828   }
829 
830   /// Set up the last cleanup that was pushed as a conditional
831   /// full-expression cleanup.
832   void initFullExprCleanup() {
833     initFullExprCleanupWithFlag(createCleanupActiveFlag());
834   }
835 
836   void initFullExprCleanupWithFlag(Address ActiveFlag);
837   Address createCleanupActiveFlag();
838 
839   /// PushDestructorCleanup - Push a cleanup to call the
840   /// complete-object destructor of an object of the given type at the
841   /// given address.  Does nothing if T is not a C++ class type with a
842   /// non-trivial destructor.
843   void PushDestructorCleanup(QualType T, Address Addr);
844 
845   /// PushDestructorCleanup - Push a cleanup to call the
846   /// complete-object variant of the given destructor on the object at
847   /// the given address.
848   void PushDestructorCleanup(const CXXDestructorDecl *Dtor, QualType T,
849                              Address Addr);
850 
851   /// PopCleanupBlock - Will pop the cleanup entry on the stack and
852   /// process all branch fixups.
853   void PopCleanupBlock(bool FallThroughIsBranchThrough = false);
854 
855   /// DeactivateCleanupBlock - Deactivates the given cleanup block.
856   /// The block cannot be reactivated.  Pops it if it's the top of the
857   /// stack.
858   ///
859   /// \param DominatingIP - An instruction which is known to
860   ///   dominate the current IP (if set) and which lies along
861   ///   all paths of execution between the current IP and the
862   ///   the point at which the cleanup comes into scope.
863   void DeactivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
864                               llvm::Instruction *DominatingIP);
865 
866   /// ActivateCleanupBlock - Activates an initially-inactive cleanup.
867   /// Cannot be used to resurrect a deactivated cleanup.
868   ///
869   /// \param DominatingIP - An instruction which is known to
870   ///   dominate the current IP (if set) and which lies along
871   ///   all paths of execution between the current IP and the
872   ///   the point at which the cleanup comes into scope.
873   void ActivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
874                             llvm::Instruction *DominatingIP);
875 
876   /// Enters a new scope for capturing cleanups, all of which
877   /// will be executed once the scope is exited.
878   class RunCleanupsScope {
879     EHScopeStack::stable_iterator CleanupStackDepth, OldCleanupScopeDepth;
880     size_t LifetimeExtendedCleanupStackSize;
881     bool OldDidCallStackSave;
882   protected:
883     bool PerformCleanup;
884   private:
885 
886     RunCleanupsScope(const RunCleanupsScope &) = delete;
887     void operator=(const RunCleanupsScope &) = delete;
888 
889   protected:
890     CodeGenFunction& CGF;
891 
892   public:
893     /// Enter a new cleanup scope.
894     explicit RunCleanupsScope(CodeGenFunction &CGF)
895       : PerformCleanup(true), CGF(CGF)
896     {
897       CleanupStackDepth = CGF.EHStack.stable_begin();
898       LifetimeExtendedCleanupStackSize =
899           CGF.LifetimeExtendedCleanupStack.size();
900       OldDidCallStackSave = CGF.DidCallStackSave;
901       CGF.DidCallStackSave = false;
902       OldCleanupScopeDepth = CGF.CurrentCleanupScopeDepth;
903       CGF.CurrentCleanupScopeDepth = CleanupStackDepth;
904     }
905 
906     /// Exit this cleanup scope, emitting any accumulated cleanups.
907     ~RunCleanupsScope() {
908       if (PerformCleanup)
909         ForceCleanup();
910     }
911 
912     /// Determine whether this scope requires any cleanups.
913     bool requiresCleanups() const {
914       return CGF.EHStack.stable_begin() != CleanupStackDepth;
915     }
916 
917     /// Force the emission of cleanups now, instead of waiting
918     /// until this object is destroyed.
919     /// \param ValuesToReload - A list of values that need to be available at
920     /// the insertion point after cleanup emission. If cleanup emission created
921     /// a shared cleanup block, these value pointers will be rewritten.
922     /// Otherwise, they not will be modified.
923     void ForceCleanup(std::initializer_list<llvm::Value**> ValuesToReload = {}) {
924       assert(PerformCleanup && "Already forced cleanup");
925       CGF.DidCallStackSave = OldDidCallStackSave;
926       CGF.PopCleanupBlocks(CleanupStackDepth, LifetimeExtendedCleanupStackSize,
927                            ValuesToReload);
928       PerformCleanup = false;
929       CGF.CurrentCleanupScopeDepth = OldCleanupScopeDepth;
930     }
931   };
932 
933   // Cleanup stack depth of the RunCleanupsScope that was pushed most recently.
934   EHScopeStack::stable_iterator CurrentCleanupScopeDepth =
935       EHScopeStack::stable_end();
936 
937   class LexicalScope : public RunCleanupsScope {
938     SourceRange Range;
939     SmallVector<const LabelDecl*, 4> Labels;
940     LexicalScope *ParentScope;
941 
942     LexicalScope(const LexicalScope &) = delete;
943     void operator=(const LexicalScope &) = delete;
944 
945   public:
946     /// Enter a new cleanup scope.
947     explicit LexicalScope(CodeGenFunction &CGF, SourceRange Range)
948       : RunCleanupsScope(CGF), Range(Range), ParentScope(CGF.CurLexicalScope) {
949       CGF.CurLexicalScope = this;
950       if (CGDebugInfo *DI = CGF.getDebugInfo())
951         DI->EmitLexicalBlockStart(CGF.Builder, Range.getBegin());
952     }
953 
954     void addLabel(const LabelDecl *label) {
955       assert(PerformCleanup && "adding label to dead scope?");
956       Labels.push_back(label);
957     }
958 
959     /// Exit this cleanup scope, emitting any accumulated
960     /// cleanups.
961     ~LexicalScope() {
962       if (CGDebugInfo *DI = CGF.getDebugInfo())
963         DI->EmitLexicalBlockEnd(CGF.Builder, Range.getEnd());
964 
965       // If we should perform a cleanup, force them now.  Note that
966       // this ends the cleanup scope before rescoping any labels.
967       if (PerformCleanup) {
968         ApplyDebugLocation DL(CGF, Range.getEnd());
969         ForceCleanup();
970       }
971     }
972 
973     /// Force the emission of cleanups now, instead of waiting
974     /// until this object is destroyed.
975     void ForceCleanup() {
976       CGF.CurLexicalScope = ParentScope;
977       RunCleanupsScope::ForceCleanup();
978 
979       if (!Labels.empty())
980         rescopeLabels();
981     }
982 
983     bool hasLabels() const {
984       return !Labels.empty();
985     }
986 
987     void rescopeLabels();
988   };
989 
990   typedef llvm::DenseMap<const Decl *, Address> DeclMapTy;
991 
992   /// The class used to assign some variables some temporarily addresses.
993   class OMPMapVars {
994     DeclMapTy SavedLocals;
995     DeclMapTy SavedTempAddresses;
996     OMPMapVars(const OMPMapVars &) = delete;
997     void operator=(const OMPMapVars &) = delete;
998 
999   public:
1000     explicit OMPMapVars() = default;
1001     ~OMPMapVars() {
1002       assert(SavedLocals.empty() && "Did not restored original addresses.");
1003     };
1004 
1005     /// Sets the address of the variable \p LocalVD to be \p TempAddr in
1006     /// function \p CGF.
1007     /// \return true if at least one variable was set already, false otherwise.
1008     bool setVarAddr(CodeGenFunction &CGF, const VarDecl *LocalVD,
1009                     Address TempAddr) {
1010       LocalVD = LocalVD->getCanonicalDecl();
1011       // Only save it once.
1012       if (SavedLocals.count(LocalVD)) return false;
1013 
1014       // Copy the existing local entry to SavedLocals.
1015       auto it = CGF.LocalDeclMap.find(LocalVD);
1016       if (it != CGF.LocalDeclMap.end())
1017         SavedLocals.try_emplace(LocalVD, it->second);
1018       else
1019         SavedLocals.try_emplace(LocalVD, Address::invalid());
1020 
1021       // Generate the private entry.
1022       QualType VarTy = LocalVD->getType();
1023       if (VarTy->isReferenceType()) {
1024         Address Temp = CGF.CreateMemTemp(VarTy);
1025         CGF.Builder.CreateStore(TempAddr.getPointer(), Temp);
1026         TempAddr = Temp;
1027       }
1028       SavedTempAddresses.try_emplace(LocalVD, TempAddr);
1029 
1030       return true;
1031     }
1032 
1033     /// Applies new addresses to the list of the variables.
1034     /// \return true if at least one variable is using new address, false
1035     /// otherwise.
1036     bool apply(CodeGenFunction &CGF) {
1037       copyInto(SavedTempAddresses, CGF.LocalDeclMap);
1038       SavedTempAddresses.clear();
1039       return !SavedLocals.empty();
1040     }
1041 
1042     /// Restores original addresses of the variables.
1043     void restore(CodeGenFunction &CGF) {
1044       if (!SavedLocals.empty()) {
1045         copyInto(SavedLocals, CGF.LocalDeclMap);
1046         SavedLocals.clear();
1047       }
1048     }
1049 
1050   private:
1051     /// Copy all the entries in the source map over the corresponding
1052     /// entries in the destination, which must exist.
1053     static void copyInto(const DeclMapTy &Src, DeclMapTy &Dest) {
1054       for (auto &Pair : Src) {
1055         if (!Pair.second.isValid()) {
1056           Dest.erase(Pair.first);
1057           continue;
1058         }
1059 
1060         auto I = Dest.find(Pair.first);
1061         if (I != Dest.end())
1062           I->second = Pair.second;
1063         else
1064           Dest.insert(Pair);
1065       }
1066     }
1067   };
1068 
1069   /// The scope used to remap some variables as private in the OpenMP loop body
1070   /// (or other captured region emitted without outlining), and to restore old
1071   /// vars back on exit.
1072   class OMPPrivateScope : public RunCleanupsScope {
1073     OMPMapVars MappedVars;
1074     OMPPrivateScope(const OMPPrivateScope &) = delete;
1075     void operator=(const OMPPrivateScope &) = delete;
1076 
1077   public:
1078     /// Enter a new OpenMP private scope.
1079     explicit OMPPrivateScope(CodeGenFunction &CGF) : RunCleanupsScope(CGF) {}
1080 
1081     /// Registers \p LocalVD variable as a private with \p Addr as the address
1082     /// of the corresponding private variable. \p
1083     /// PrivateGen is the address of the generated private variable.
1084     /// \return true if the variable is registered as private, false if it has
1085     /// been privatized already.
1086     bool addPrivate(const VarDecl *LocalVD, Address Addr) {
1087       assert(PerformCleanup && "adding private to dead scope");
1088       return MappedVars.setVarAddr(CGF, LocalVD, Addr);
1089     }
1090 
1091     /// Privatizes local variables previously registered as private.
1092     /// Registration is separate from the actual privatization to allow
1093     /// initializers use values of the original variables, not the private one.
1094     /// This is important, for example, if the private variable is a class
1095     /// variable initialized by a constructor that references other private
1096     /// variables. But at initialization original variables must be used, not
1097     /// private copies.
1098     /// \return true if at least one variable was privatized, false otherwise.
1099     bool Privatize() { return MappedVars.apply(CGF); }
1100 
1101     void ForceCleanup() {
1102       RunCleanupsScope::ForceCleanup();
1103       restoreMap();
1104     }
1105 
1106     /// Exit scope - all the mapped variables are restored.
1107     ~OMPPrivateScope() {
1108       if (PerformCleanup)
1109         ForceCleanup();
1110     }
1111 
1112     /// Checks if the global variable is captured in current function.
1113     bool isGlobalVarCaptured(const VarDecl *VD) const {
1114       VD = VD->getCanonicalDecl();
1115       return !VD->isLocalVarDeclOrParm() && CGF.LocalDeclMap.count(VD) > 0;
1116     }
1117 
1118     /// Restore all mapped variables w/o clean up. This is usefully when we want
1119     /// to reference the original variables but don't want the clean up because
1120     /// that could emit lifetime end too early, causing backend issue #56913.
1121     void restoreMap() { MappedVars.restore(CGF); }
1122   };
1123 
1124   /// Save/restore original map of previously emitted local vars in case when we
1125   /// need to duplicate emission of the same code several times in the same
1126   /// function for OpenMP code.
1127   class OMPLocalDeclMapRAII {
1128     CodeGenFunction &CGF;
1129     DeclMapTy SavedMap;
1130 
1131   public:
1132     OMPLocalDeclMapRAII(CodeGenFunction &CGF)
1133         : CGF(CGF), SavedMap(CGF.LocalDeclMap) {}
1134     ~OMPLocalDeclMapRAII() { SavedMap.swap(CGF.LocalDeclMap); }
1135   };
1136 
1137   /// Takes the old cleanup stack size and emits the cleanup blocks
1138   /// that have been added.
1139   void
1140   PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
1141                    std::initializer_list<llvm::Value **> ValuesToReload = {});
1142 
1143   /// Takes the old cleanup stack size and emits the cleanup blocks
1144   /// that have been added, then adds all lifetime-extended cleanups from
1145   /// the given position to the stack.
1146   void
1147   PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
1148                    size_t OldLifetimeExtendedStackSize,
1149                    std::initializer_list<llvm::Value **> ValuesToReload = {});
1150 
1151   void ResolveBranchFixups(llvm::BasicBlock *Target);
1152 
1153   /// The given basic block lies in the current EH scope, but may be a
1154   /// target of a potentially scope-crossing jump; get a stable handle
1155   /// to which we can perform this jump later.
1156   JumpDest getJumpDestInCurrentScope(llvm::BasicBlock *Target) {
1157     return JumpDest(Target,
1158                     EHStack.getInnermostNormalCleanup(),
1159                     NextCleanupDestIndex++);
1160   }
1161 
1162   /// The given basic block lies in the current EH scope, but may be a
1163   /// target of a potentially scope-crossing jump; get a stable handle
1164   /// to which we can perform this jump later.
1165   JumpDest getJumpDestInCurrentScope(StringRef Name = StringRef()) {
1166     return getJumpDestInCurrentScope(createBasicBlock(Name));
1167   }
1168 
1169   /// EmitBranchThroughCleanup - Emit a branch from the current insert
1170   /// block through the normal cleanup handling code (if any) and then
1171   /// on to \arg Dest.
1172   void EmitBranchThroughCleanup(JumpDest Dest);
1173 
1174   /// isObviouslyBranchWithoutCleanups - Return true if a branch to the
1175   /// specified destination obviously has no cleanups to run.  'false' is always
1176   /// a conservatively correct answer for this method.
1177   bool isObviouslyBranchWithoutCleanups(JumpDest Dest) const;
1178 
1179   /// popCatchScope - Pops the catch scope at the top of the EHScope
1180   /// stack, emitting any required code (other than the catch handlers
1181   /// themselves).
1182   void popCatchScope();
1183 
1184   llvm::BasicBlock *getEHResumeBlock(bool isCleanup);
1185   llvm::BasicBlock *getEHDispatchBlock(EHScopeStack::stable_iterator scope);
1186   llvm::BasicBlock *
1187   getFuncletEHDispatchBlock(EHScopeStack::stable_iterator scope);
1188 
1189   /// An object to manage conditionally-evaluated expressions.
1190   class ConditionalEvaluation {
1191     llvm::BasicBlock *StartBB;
1192 
1193   public:
1194     ConditionalEvaluation(CodeGenFunction &CGF)
1195       : StartBB(CGF.Builder.GetInsertBlock()) {}
1196 
1197     void begin(CodeGenFunction &CGF) {
1198       assert(CGF.OutermostConditional != this);
1199       if (!CGF.OutermostConditional)
1200         CGF.OutermostConditional = this;
1201     }
1202 
1203     void end(CodeGenFunction &CGF) {
1204       assert(CGF.OutermostConditional != nullptr);
1205       if (CGF.OutermostConditional == this)
1206         CGF.OutermostConditional = nullptr;
1207     }
1208 
1209     /// Returns a block which will be executed prior to each
1210     /// evaluation of the conditional code.
1211     llvm::BasicBlock *getStartingBlock() const {
1212       return StartBB;
1213     }
1214   };
1215 
1216   /// isInConditionalBranch - Return true if we're currently emitting
1217   /// one branch or the other of a conditional expression.
1218   bool isInConditionalBranch() const { return OutermostConditional != nullptr; }
1219 
1220   void setBeforeOutermostConditional(llvm::Value *value, Address addr) {
1221     assert(isInConditionalBranch());
1222     llvm::BasicBlock *block = OutermostConditional->getStartingBlock();
1223     auto store = new llvm::StoreInst(value, addr.getPointer(), &block->back());
1224     store->setAlignment(addr.getAlignment().getAsAlign());
1225   }
1226 
1227   /// An RAII object to record that we're evaluating a statement
1228   /// expression.
1229   class StmtExprEvaluation {
1230     CodeGenFunction &CGF;
1231 
1232     /// We have to save the outermost conditional: cleanups in a
1233     /// statement expression aren't conditional just because the
1234     /// StmtExpr is.
1235     ConditionalEvaluation *SavedOutermostConditional;
1236 
1237   public:
1238     StmtExprEvaluation(CodeGenFunction &CGF)
1239       : CGF(CGF), SavedOutermostConditional(CGF.OutermostConditional) {
1240       CGF.OutermostConditional = nullptr;
1241     }
1242 
1243     ~StmtExprEvaluation() {
1244       CGF.OutermostConditional = SavedOutermostConditional;
1245       CGF.EnsureInsertPoint();
1246     }
1247   };
1248 
1249   /// An object which temporarily prevents a value from being
1250   /// destroyed by aggressive peephole optimizations that assume that
1251   /// all uses of a value have been realized in the IR.
1252   class PeepholeProtection {
1253     llvm::Instruction *Inst;
1254     friend class CodeGenFunction;
1255 
1256   public:
1257     PeepholeProtection() : Inst(nullptr) {}
1258   };
1259 
1260   /// A non-RAII class containing all the information about a bound
1261   /// opaque value.  OpaqueValueMapping, below, is a RAII wrapper for
1262   /// this which makes individual mappings very simple; using this
1263   /// class directly is useful when you have a variable number of
1264   /// opaque values or don't want the RAII functionality for some
1265   /// reason.
1266   class OpaqueValueMappingData {
1267     const OpaqueValueExpr *OpaqueValue;
1268     bool BoundLValue;
1269     CodeGenFunction::PeepholeProtection Protection;
1270 
1271     OpaqueValueMappingData(const OpaqueValueExpr *ov,
1272                            bool boundLValue)
1273       : OpaqueValue(ov), BoundLValue(boundLValue) {}
1274   public:
1275     OpaqueValueMappingData() : OpaqueValue(nullptr) {}
1276 
1277     static bool shouldBindAsLValue(const Expr *expr) {
1278       // gl-values should be bound as l-values for obvious reasons.
1279       // Records should be bound as l-values because IR generation
1280       // always keeps them in memory.  Expressions of function type
1281       // act exactly like l-values but are formally required to be
1282       // r-values in C.
1283       return expr->isGLValue() ||
1284              expr->getType()->isFunctionType() ||
1285              hasAggregateEvaluationKind(expr->getType());
1286     }
1287 
1288     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
1289                                        const OpaqueValueExpr *ov,
1290                                        const Expr *e) {
1291       if (shouldBindAsLValue(ov))
1292         return bind(CGF, ov, CGF.EmitLValue(e));
1293       return bind(CGF, ov, CGF.EmitAnyExpr(e));
1294     }
1295 
1296     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
1297                                        const OpaqueValueExpr *ov,
1298                                        const LValue &lv) {
1299       assert(shouldBindAsLValue(ov));
1300       CGF.OpaqueLValues.insert(std::make_pair(ov, lv));
1301       return OpaqueValueMappingData(ov, true);
1302     }
1303 
1304     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
1305                                        const OpaqueValueExpr *ov,
1306                                        const RValue &rv) {
1307       assert(!shouldBindAsLValue(ov));
1308       CGF.OpaqueRValues.insert(std::make_pair(ov, rv));
1309 
1310       OpaqueValueMappingData data(ov, false);
1311 
1312       // Work around an extremely aggressive peephole optimization in
1313       // EmitScalarConversion which assumes that all other uses of a
1314       // value are extant.
1315       data.Protection = CGF.protectFromPeepholes(rv);
1316 
1317       return data;
1318     }
1319 
1320     bool isValid() const { return OpaqueValue != nullptr; }
1321     void clear() { OpaqueValue = nullptr; }
1322 
1323     void unbind(CodeGenFunction &CGF) {
1324       assert(OpaqueValue && "no data to unbind!");
1325 
1326       if (BoundLValue) {
1327         CGF.OpaqueLValues.erase(OpaqueValue);
1328       } else {
1329         CGF.OpaqueRValues.erase(OpaqueValue);
1330         CGF.unprotectFromPeepholes(Protection);
1331       }
1332     }
1333   };
1334 
1335   /// An RAII object to set (and then clear) a mapping for an OpaqueValueExpr.
1336   class OpaqueValueMapping {
1337     CodeGenFunction &CGF;
1338     OpaqueValueMappingData Data;
1339 
1340   public:
1341     static bool shouldBindAsLValue(const Expr *expr) {
1342       return OpaqueValueMappingData::shouldBindAsLValue(expr);
1343     }
1344 
1345     /// Build the opaque value mapping for the given conditional
1346     /// operator if it's the GNU ?: extension.  This is a common
1347     /// enough pattern that the convenience operator is really
1348     /// helpful.
1349     ///
1350     OpaqueValueMapping(CodeGenFunction &CGF,
1351                        const AbstractConditionalOperator *op) : CGF(CGF) {
1352       if (isa<ConditionalOperator>(op))
1353         // Leave Data empty.
1354         return;
1355 
1356       const BinaryConditionalOperator *e = cast<BinaryConditionalOperator>(op);
1357       Data = OpaqueValueMappingData::bind(CGF, e->getOpaqueValue(),
1358                                           e->getCommon());
1359     }
1360 
1361     /// Build the opaque value mapping for an OpaqueValueExpr whose source
1362     /// expression is set to the expression the OVE represents.
1363     OpaqueValueMapping(CodeGenFunction &CGF, const OpaqueValueExpr *OV)
1364         : CGF(CGF) {
1365       if (OV) {
1366         assert(OV->getSourceExpr() && "wrong form of OpaqueValueMapping used "
1367                                       "for OVE with no source expression");
1368         Data = OpaqueValueMappingData::bind(CGF, OV, OV->getSourceExpr());
1369       }
1370     }
1371 
1372     OpaqueValueMapping(CodeGenFunction &CGF,
1373                        const OpaqueValueExpr *opaqueValue,
1374                        LValue lvalue)
1375       : CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, lvalue)) {
1376     }
1377 
1378     OpaqueValueMapping(CodeGenFunction &CGF,
1379                        const OpaqueValueExpr *opaqueValue,
1380                        RValue rvalue)
1381       : CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, rvalue)) {
1382     }
1383 
1384     void pop() {
1385       Data.unbind(CGF);
1386       Data.clear();
1387     }
1388 
1389     ~OpaqueValueMapping() {
1390       if (Data.isValid()) Data.unbind(CGF);
1391     }
1392   };
1393 
1394 private:
1395   CGDebugInfo *DebugInfo;
1396   /// Used to create unique names for artificial VLA size debug info variables.
1397   unsigned VLAExprCounter = 0;
1398   bool DisableDebugInfo = false;
1399 
1400   /// DidCallStackSave - Whether llvm.stacksave has been called. Used to avoid
1401   /// calling llvm.stacksave for multiple VLAs in the same scope.
1402   bool DidCallStackSave = false;
1403 
1404   /// IndirectBranch - The first time an indirect goto is seen we create a block
1405   /// with an indirect branch.  Every time we see the address of a label taken,
1406   /// we add the label to the indirect goto.  Every subsequent indirect goto is
1407   /// codegen'd as a jump to the IndirectBranch's basic block.
1408   llvm::IndirectBrInst *IndirectBranch = nullptr;
1409 
1410   /// LocalDeclMap - This keeps track of the LLVM allocas or globals for local C
1411   /// decls.
1412   DeclMapTy LocalDeclMap;
1413 
1414   // Keep track of the cleanups for callee-destructed parameters pushed to the
1415   // cleanup stack so that they can be deactivated later.
1416   llvm::DenseMap<const ParmVarDecl *, EHScopeStack::stable_iterator>
1417       CalleeDestructedParamCleanups;
1418 
1419   /// SizeArguments - If a ParmVarDecl had the pass_object_size attribute, this
1420   /// will contain a mapping from said ParmVarDecl to its implicit "object_size"
1421   /// parameter.
1422   llvm::SmallDenseMap<const ParmVarDecl *, const ImplicitParamDecl *, 2>
1423       SizeArguments;
1424 
1425   /// Track escaped local variables with auto storage. Used during SEH
1426   /// outlining to produce a call to llvm.localescape.
1427   llvm::DenseMap<llvm::AllocaInst *, int> EscapedLocals;
1428 
1429   /// LabelMap - This keeps track of the LLVM basic block for each C label.
1430   llvm::DenseMap<const LabelDecl*, JumpDest> LabelMap;
1431 
1432   // BreakContinueStack - This keeps track of where break and continue
1433   // statements should jump to.
1434   struct BreakContinue {
1435     BreakContinue(JumpDest Break, JumpDest Continue)
1436       : BreakBlock(Break), ContinueBlock(Continue) {}
1437 
1438     JumpDest BreakBlock;
1439     JumpDest ContinueBlock;
1440   };
1441   SmallVector<BreakContinue, 8> BreakContinueStack;
1442 
1443   /// Handles cancellation exit points in OpenMP-related constructs.
1444   class OpenMPCancelExitStack {
1445     /// Tracks cancellation exit point and join point for cancel-related exit
1446     /// and normal exit.
1447     struct CancelExit {
1448       CancelExit() = default;
1449       CancelExit(OpenMPDirectiveKind Kind, JumpDest ExitBlock,
1450                  JumpDest ContBlock)
1451           : Kind(Kind), ExitBlock(ExitBlock), ContBlock(ContBlock) {}
1452       OpenMPDirectiveKind Kind = llvm::omp::OMPD_unknown;
1453       /// true if the exit block has been emitted already by the special
1454       /// emitExit() call, false if the default codegen is used.
1455       bool HasBeenEmitted = false;
1456       JumpDest ExitBlock;
1457       JumpDest ContBlock;
1458     };
1459 
1460     SmallVector<CancelExit, 8> Stack;
1461 
1462   public:
1463     OpenMPCancelExitStack() : Stack(1) {}
1464     ~OpenMPCancelExitStack() = default;
1465     /// Fetches the exit block for the current OpenMP construct.
1466     JumpDest getExitBlock() const { return Stack.back().ExitBlock; }
1467     /// Emits exit block with special codegen procedure specific for the related
1468     /// OpenMP construct + emits code for normal construct cleanup.
1469     void emitExit(CodeGenFunction &CGF, OpenMPDirectiveKind Kind,
1470                   const llvm::function_ref<void(CodeGenFunction &)> CodeGen) {
1471       if (Stack.back().Kind == Kind && getExitBlock().isValid()) {
1472         assert(CGF.getOMPCancelDestination(Kind).isValid());
1473         assert(CGF.HaveInsertPoint());
1474         assert(!Stack.back().HasBeenEmitted);
1475         auto IP = CGF.Builder.saveAndClearIP();
1476         CGF.EmitBlock(Stack.back().ExitBlock.getBlock());
1477         CodeGen(CGF);
1478         CGF.EmitBranch(Stack.back().ContBlock.getBlock());
1479         CGF.Builder.restoreIP(IP);
1480         Stack.back().HasBeenEmitted = true;
1481       }
1482       CodeGen(CGF);
1483     }
1484     /// Enter the cancel supporting \a Kind construct.
1485     /// \param Kind OpenMP directive that supports cancel constructs.
1486     /// \param HasCancel true, if the construct has inner cancel directive,
1487     /// false otherwise.
1488     void enter(CodeGenFunction &CGF, OpenMPDirectiveKind Kind, bool HasCancel) {
1489       Stack.push_back({Kind,
1490                        HasCancel ? CGF.getJumpDestInCurrentScope("cancel.exit")
1491                                  : JumpDest(),
1492                        HasCancel ? CGF.getJumpDestInCurrentScope("cancel.cont")
1493                                  : JumpDest()});
1494     }
1495     /// Emits default exit point for the cancel construct (if the special one
1496     /// has not be used) + join point for cancel/normal exits.
1497     void exit(CodeGenFunction &CGF) {
1498       if (getExitBlock().isValid()) {
1499         assert(CGF.getOMPCancelDestination(Stack.back().Kind).isValid());
1500         bool HaveIP = CGF.HaveInsertPoint();
1501         if (!Stack.back().HasBeenEmitted) {
1502           if (HaveIP)
1503             CGF.EmitBranchThroughCleanup(Stack.back().ContBlock);
1504           CGF.EmitBlock(Stack.back().ExitBlock.getBlock());
1505           CGF.EmitBranchThroughCleanup(Stack.back().ContBlock);
1506         }
1507         CGF.EmitBlock(Stack.back().ContBlock.getBlock());
1508         if (!HaveIP) {
1509           CGF.Builder.CreateUnreachable();
1510           CGF.Builder.ClearInsertionPoint();
1511         }
1512       }
1513       Stack.pop_back();
1514     }
1515   };
1516   OpenMPCancelExitStack OMPCancelStack;
1517 
1518   /// Lower the Likelihood knowledge about the \p Cond via llvm.expect intrin.
1519   llvm::Value *emitCondLikelihoodViaExpectIntrinsic(llvm::Value *Cond,
1520                                                     Stmt::Likelihood LH);
1521 
1522   CodeGenPGO PGO;
1523 
1524   /// Calculate branch weights appropriate for PGO data
1525   llvm::MDNode *createProfileWeights(uint64_t TrueCount,
1526                                      uint64_t FalseCount) const;
1527   llvm::MDNode *createProfileWeights(ArrayRef<uint64_t> Weights) const;
1528   llvm::MDNode *createProfileWeightsForLoop(const Stmt *Cond,
1529                                             uint64_t LoopCount) const;
1530 
1531 public:
1532   /// Increment the profiler's counter for the given statement by \p StepV.
1533   /// If \p StepV is null, the default increment is 1.
1534   void incrementProfileCounter(const Stmt *S, llvm::Value *StepV = nullptr) {
1535     if (CGM.getCodeGenOpts().hasProfileClangInstr() &&
1536         !CurFn->hasFnAttribute(llvm::Attribute::NoProfile) &&
1537         !CurFn->hasFnAttribute(llvm::Attribute::SkipProfile))
1538       PGO.emitCounterIncrement(Builder, S, StepV);
1539     PGO.setCurrentStmt(S);
1540   }
1541 
1542   /// Get the profiler's count for the given statement.
1543   uint64_t getProfileCount(const Stmt *S) {
1544     return PGO.getStmtCount(S).value_or(0);
1545   }
1546 
1547   /// Set the profiler's current count.
1548   void setCurrentProfileCount(uint64_t Count) {
1549     PGO.setCurrentRegionCount(Count);
1550   }
1551 
1552   /// Get the profiler's current count. This is generally the count for the most
1553   /// recently incremented counter.
1554   uint64_t getCurrentProfileCount() {
1555     return PGO.getCurrentRegionCount();
1556   }
1557 
1558 private:
1559 
1560   /// SwitchInsn - This is nearest current switch instruction. It is null if
1561   /// current context is not in a switch.
1562   llvm::SwitchInst *SwitchInsn = nullptr;
1563   /// The branch weights of SwitchInsn when doing instrumentation based PGO.
1564   SmallVector<uint64_t, 16> *SwitchWeights = nullptr;
1565 
1566   /// The likelihood attributes of the SwitchCase.
1567   SmallVector<Stmt::Likelihood, 16> *SwitchLikelihood = nullptr;
1568 
1569   /// CaseRangeBlock - This block holds if condition check for last case
1570   /// statement range in current switch instruction.
1571   llvm::BasicBlock *CaseRangeBlock = nullptr;
1572 
1573   /// OpaqueLValues - Keeps track of the current set of opaque value
1574   /// expressions.
1575   llvm::DenseMap<const OpaqueValueExpr *, LValue> OpaqueLValues;
1576   llvm::DenseMap<const OpaqueValueExpr *, RValue> OpaqueRValues;
1577 
1578   // VLASizeMap - This keeps track of the associated size for each VLA type.
1579   // We track this by the size expression rather than the type itself because
1580   // in certain situations, like a const qualifier applied to an VLA typedef,
1581   // multiple VLA types can share the same size expression.
1582   // FIXME: Maybe this could be a stack of maps that is pushed/popped as we
1583   // enter/leave scopes.
1584   llvm::DenseMap<const Expr*, llvm::Value*> VLASizeMap;
1585 
1586   /// A block containing a single 'unreachable' instruction.  Created
1587   /// lazily by getUnreachableBlock().
1588   llvm::BasicBlock *UnreachableBlock = nullptr;
1589 
1590   /// Counts of the number return expressions in the function.
1591   unsigned NumReturnExprs = 0;
1592 
1593   /// Count the number of simple (constant) return expressions in the function.
1594   unsigned NumSimpleReturnExprs = 0;
1595 
1596   /// The last regular (non-return) debug location (breakpoint) in the function.
1597   SourceLocation LastStopPoint;
1598 
1599 public:
1600   /// Source location information about the default argument or member
1601   /// initializer expression we're evaluating, if any.
1602   CurrentSourceLocExprScope CurSourceLocExprScope;
1603   using SourceLocExprScopeGuard =
1604       CurrentSourceLocExprScope::SourceLocExprScopeGuard;
1605 
1606   /// A scope within which we are constructing the fields of an object which
1607   /// might use a CXXDefaultInitExpr. This stashes away a 'this' value to use
1608   /// if we need to evaluate a CXXDefaultInitExpr within the evaluation.
1609   class FieldConstructionScope {
1610   public:
1611     FieldConstructionScope(CodeGenFunction &CGF, Address This)
1612         : CGF(CGF), OldCXXDefaultInitExprThis(CGF.CXXDefaultInitExprThis) {
1613       CGF.CXXDefaultInitExprThis = This;
1614     }
1615     ~FieldConstructionScope() {
1616       CGF.CXXDefaultInitExprThis = OldCXXDefaultInitExprThis;
1617     }
1618 
1619   private:
1620     CodeGenFunction &CGF;
1621     Address OldCXXDefaultInitExprThis;
1622   };
1623 
1624   /// The scope of a CXXDefaultInitExpr. Within this scope, the value of 'this'
1625   /// is overridden to be the object under construction.
1626   class CXXDefaultInitExprScope  {
1627   public:
1628     CXXDefaultInitExprScope(CodeGenFunction &CGF, const CXXDefaultInitExpr *E)
1629         : CGF(CGF), OldCXXThisValue(CGF.CXXThisValue),
1630           OldCXXThisAlignment(CGF.CXXThisAlignment),
1631           SourceLocScope(E, CGF.CurSourceLocExprScope) {
1632       CGF.CXXThisValue = CGF.CXXDefaultInitExprThis.getPointer();
1633       CGF.CXXThisAlignment = CGF.CXXDefaultInitExprThis.getAlignment();
1634     }
1635     ~CXXDefaultInitExprScope() {
1636       CGF.CXXThisValue = OldCXXThisValue;
1637       CGF.CXXThisAlignment = OldCXXThisAlignment;
1638     }
1639 
1640   public:
1641     CodeGenFunction &CGF;
1642     llvm::Value *OldCXXThisValue;
1643     CharUnits OldCXXThisAlignment;
1644     SourceLocExprScopeGuard SourceLocScope;
1645   };
1646 
1647   struct CXXDefaultArgExprScope : SourceLocExprScopeGuard {
1648     CXXDefaultArgExprScope(CodeGenFunction &CGF, const CXXDefaultArgExpr *E)
1649         : SourceLocExprScopeGuard(E, CGF.CurSourceLocExprScope) {}
1650   };
1651 
1652   /// The scope of an ArrayInitLoopExpr. Within this scope, the value of the
1653   /// current loop index is overridden.
1654   class ArrayInitLoopExprScope {
1655   public:
1656     ArrayInitLoopExprScope(CodeGenFunction &CGF, llvm::Value *Index)
1657       : CGF(CGF), OldArrayInitIndex(CGF.ArrayInitIndex) {
1658       CGF.ArrayInitIndex = Index;
1659     }
1660     ~ArrayInitLoopExprScope() {
1661       CGF.ArrayInitIndex = OldArrayInitIndex;
1662     }
1663 
1664   private:
1665     CodeGenFunction &CGF;
1666     llvm::Value *OldArrayInitIndex;
1667   };
1668 
1669   class InlinedInheritingConstructorScope {
1670   public:
1671     InlinedInheritingConstructorScope(CodeGenFunction &CGF, GlobalDecl GD)
1672         : CGF(CGF), OldCurGD(CGF.CurGD), OldCurFuncDecl(CGF.CurFuncDecl),
1673           OldCurCodeDecl(CGF.CurCodeDecl),
1674           OldCXXABIThisDecl(CGF.CXXABIThisDecl),
1675           OldCXXABIThisValue(CGF.CXXABIThisValue),
1676           OldCXXThisValue(CGF.CXXThisValue),
1677           OldCXXABIThisAlignment(CGF.CXXABIThisAlignment),
1678           OldCXXThisAlignment(CGF.CXXThisAlignment),
1679           OldReturnValue(CGF.ReturnValue), OldFnRetTy(CGF.FnRetTy),
1680           OldCXXInheritedCtorInitExprArgs(
1681               std::move(CGF.CXXInheritedCtorInitExprArgs)) {
1682       CGF.CurGD = GD;
1683       CGF.CurFuncDecl = CGF.CurCodeDecl =
1684           cast<CXXConstructorDecl>(GD.getDecl());
1685       CGF.CXXABIThisDecl = nullptr;
1686       CGF.CXXABIThisValue = nullptr;
1687       CGF.CXXThisValue = nullptr;
1688       CGF.CXXABIThisAlignment = CharUnits();
1689       CGF.CXXThisAlignment = CharUnits();
1690       CGF.ReturnValue = Address::invalid();
1691       CGF.FnRetTy = QualType();
1692       CGF.CXXInheritedCtorInitExprArgs.clear();
1693     }
1694     ~InlinedInheritingConstructorScope() {
1695       CGF.CurGD = OldCurGD;
1696       CGF.CurFuncDecl = OldCurFuncDecl;
1697       CGF.CurCodeDecl = OldCurCodeDecl;
1698       CGF.CXXABIThisDecl = OldCXXABIThisDecl;
1699       CGF.CXXABIThisValue = OldCXXABIThisValue;
1700       CGF.CXXThisValue = OldCXXThisValue;
1701       CGF.CXXABIThisAlignment = OldCXXABIThisAlignment;
1702       CGF.CXXThisAlignment = OldCXXThisAlignment;
1703       CGF.ReturnValue = OldReturnValue;
1704       CGF.FnRetTy = OldFnRetTy;
1705       CGF.CXXInheritedCtorInitExprArgs =
1706           std::move(OldCXXInheritedCtorInitExprArgs);
1707     }
1708 
1709   private:
1710     CodeGenFunction &CGF;
1711     GlobalDecl OldCurGD;
1712     const Decl *OldCurFuncDecl;
1713     const Decl *OldCurCodeDecl;
1714     ImplicitParamDecl *OldCXXABIThisDecl;
1715     llvm::Value *OldCXXABIThisValue;
1716     llvm::Value *OldCXXThisValue;
1717     CharUnits OldCXXABIThisAlignment;
1718     CharUnits OldCXXThisAlignment;
1719     Address OldReturnValue;
1720     QualType OldFnRetTy;
1721     CallArgList OldCXXInheritedCtorInitExprArgs;
1722   };
1723 
1724   // Helper class for the OpenMP IR Builder. Allows reusability of code used for
1725   // region body, and finalization codegen callbacks. This will class will also
1726   // contain privatization functions used by the privatization call backs
1727   //
1728   // TODO: this is temporary class for things that are being moved out of
1729   // CGOpenMPRuntime, new versions of current CodeGenFunction methods, or
1730   // utility function for use with the OMPBuilder. Once that move to use the
1731   // OMPBuilder is done, everything here will either become part of CodeGenFunc.
1732   // directly, or a new helper class that will contain functions used by both
1733   // this and the OMPBuilder
1734 
1735   struct OMPBuilderCBHelpers {
1736 
1737     OMPBuilderCBHelpers() = delete;
1738     OMPBuilderCBHelpers(const OMPBuilderCBHelpers &) = delete;
1739     OMPBuilderCBHelpers &operator=(const OMPBuilderCBHelpers &) = delete;
1740 
1741     using InsertPointTy = llvm::OpenMPIRBuilder::InsertPointTy;
1742 
1743     /// Cleanup action for allocate support.
1744     class OMPAllocateCleanupTy final : public EHScopeStack::Cleanup {
1745 
1746     private:
1747       llvm::CallInst *RTLFnCI;
1748 
1749     public:
1750       OMPAllocateCleanupTy(llvm::CallInst *RLFnCI) : RTLFnCI(RLFnCI) {
1751         RLFnCI->removeFromParent();
1752       }
1753 
1754       void Emit(CodeGenFunction &CGF, Flags /*flags*/) override {
1755         if (!CGF.HaveInsertPoint())
1756           return;
1757         CGF.Builder.Insert(RTLFnCI);
1758       }
1759     };
1760 
1761     /// Returns address of the threadprivate variable for the current
1762     /// thread. This Also create any necessary OMP runtime calls.
1763     ///
1764     /// \param VD VarDecl for Threadprivate variable.
1765     /// \param VDAddr Address of the Vardecl
1766     /// \param Loc  The location where the barrier directive was encountered
1767     static Address getAddrOfThreadPrivate(CodeGenFunction &CGF,
1768                                           const VarDecl *VD, Address VDAddr,
1769                                           SourceLocation Loc);
1770 
1771     /// Gets the OpenMP-specific address of the local variable /p VD.
1772     static Address getAddressOfLocalVariable(CodeGenFunction &CGF,
1773                                              const VarDecl *VD);
1774     /// Get the platform-specific name separator.
1775     /// \param Parts different parts of the final name that needs separation
1776     /// \param FirstSeparator First separator used between the initial two
1777     ///        parts of the name.
1778     /// \param Separator separator used between all of the rest consecutinve
1779     ///        parts of the name
1780     static std::string getNameWithSeparators(ArrayRef<StringRef> Parts,
1781                                              StringRef FirstSeparator = ".",
1782                                              StringRef Separator = ".");
1783     /// Emit the Finalization for an OMP region
1784     /// \param CGF	The Codegen function this belongs to
1785     /// \param IP	Insertion point for generating the finalization code.
1786     static void FinalizeOMPRegion(CodeGenFunction &CGF, InsertPointTy IP) {
1787       CGBuilderTy::InsertPointGuard IPG(CGF.Builder);
1788       assert(IP.getBlock()->end() != IP.getPoint() &&
1789              "OpenMP IR Builder should cause terminated block!");
1790 
1791       llvm::BasicBlock *IPBB = IP.getBlock();
1792       llvm::BasicBlock *DestBB = IPBB->getUniqueSuccessor();
1793       assert(DestBB && "Finalization block should have one successor!");
1794 
1795       // erase and replace with cleanup branch.
1796       IPBB->getTerminator()->eraseFromParent();
1797       CGF.Builder.SetInsertPoint(IPBB);
1798       CodeGenFunction::JumpDest Dest = CGF.getJumpDestInCurrentScope(DestBB);
1799       CGF.EmitBranchThroughCleanup(Dest);
1800     }
1801 
1802     /// Emit the body of an OMP region
1803     /// \param CGF	          The Codegen function this belongs to
1804     /// \param RegionBodyStmt The body statement for the OpenMP region being
1805     ///                       generated
1806     /// \param AllocaIP       Where to insert alloca instructions
1807     /// \param CodeGenIP      Where to insert the region code
1808     /// \param RegionName     Name to be used for new blocks
1809     static void EmitOMPInlinedRegionBody(CodeGenFunction &CGF,
1810                                          const Stmt *RegionBodyStmt,
1811                                          InsertPointTy AllocaIP,
1812                                          InsertPointTy CodeGenIP,
1813                                          Twine RegionName);
1814 
1815     static void EmitCaptureStmt(CodeGenFunction &CGF, InsertPointTy CodeGenIP,
1816                                 llvm::BasicBlock &FiniBB, llvm::Function *Fn,
1817                                 ArrayRef<llvm::Value *> Args) {
1818       llvm::BasicBlock *CodeGenIPBB = CodeGenIP.getBlock();
1819       if (llvm::Instruction *CodeGenIPBBTI = CodeGenIPBB->getTerminator())
1820         CodeGenIPBBTI->eraseFromParent();
1821 
1822       CGF.Builder.SetInsertPoint(CodeGenIPBB);
1823 
1824       if (Fn->doesNotThrow())
1825         CGF.EmitNounwindRuntimeCall(Fn, Args);
1826       else
1827         CGF.EmitRuntimeCall(Fn, Args);
1828 
1829       if (CGF.Builder.saveIP().isSet())
1830         CGF.Builder.CreateBr(&FiniBB);
1831     }
1832 
1833     /// Emit the body of an OMP region that will be outlined in
1834     /// OpenMPIRBuilder::finalize().
1835     /// \param CGF	          The Codegen function this belongs to
1836     /// \param RegionBodyStmt The body statement for the OpenMP region being
1837     ///                       generated
1838     /// \param AllocaIP       Where to insert alloca instructions
1839     /// \param CodeGenIP      Where to insert the region code
1840     /// \param RegionName     Name to be used for new blocks
1841     static void EmitOMPOutlinedRegionBody(CodeGenFunction &CGF,
1842                                           const Stmt *RegionBodyStmt,
1843                                           InsertPointTy AllocaIP,
1844                                           InsertPointTy CodeGenIP,
1845                                           Twine RegionName);
1846 
1847     /// RAII for preserving necessary info during Outlined region body codegen.
1848     class OutlinedRegionBodyRAII {
1849 
1850       llvm::AssertingVH<llvm::Instruction> OldAllocaIP;
1851       CodeGenFunction::JumpDest OldReturnBlock;
1852       CodeGenFunction &CGF;
1853 
1854     public:
1855       OutlinedRegionBodyRAII(CodeGenFunction &cgf, InsertPointTy &AllocaIP,
1856                              llvm::BasicBlock &RetBB)
1857           : CGF(cgf) {
1858         assert(AllocaIP.isSet() &&
1859                "Must specify Insertion point for allocas of outlined function");
1860         OldAllocaIP = CGF.AllocaInsertPt;
1861         CGF.AllocaInsertPt = &*AllocaIP.getPoint();
1862 
1863         OldReturnBlock = CGF.ReturnBlock;
1864         CGF.ReturnBlock = CGF.getJumpDestInCurrentScope(&RetBB);
1865       }
1866 
1867       ~OutlinedRegionBodyRAII() {
1868         CGF.AllocaInsertPt = OldAllocaIP;
1869         CGF.ReturnBlock = OldReturnBlock;
1870       }
1871     };
1872 
1873     /// RAII for preserving necessary info during inlined region body codegen.
1874     class InlinedRegionBodyRAII {
1875 
1876       llvm::AssertingVH<llvm::Instruction> OldAllocaIP;
1877       CodeGenFunction &CGF;
1878 
1879     public:
1880       InlinedRegionBodyRAII(CodeGenFunction &cgf, InsertPointTy &AllocaIP,
1881                             llvm::BasicBlock &FiniBB)
1882           : CGF(cgf) {
1883         // Alloca insertion block should be in the entry block of the containing
1884         // function so it expects an empty AllocaIP in which case will reuse the
1885         // old alloca insertion point, or a new AllocaIP in the same block as
1886         // the old one
1887         assert((!AllocaIP.isSet() ||
1888                 CGF.AllocaInsertPt->getParent() == AllocaIP.getBlock()) &&
1889                "Insertion point should be in the entry block of containing "
1890                "function!");
1891         OldAllocaIP = CGF.AllocaInsertPt;
1892         if (AllocaIP.isSet())
1893           CGF.AllocaInsertPt = &*AllocaIP.getPoint();
1894 
1895         // TODO: Remove the call, after making sure the counter is not used by
1896         //       the EHStack.
1897         // Since this is an inlined region, it should not modify the
1898         // ReturnBlock, and should reuse the one for the enclosing outlined
1899         // region. So, the JumpDest being return by the function is discarded
1900         (void)CGF.getJumpDestInCurrentScope(&FiniBB);
1901       }
1902 
1903       ~InlinedRegionBodyRAII() { CGF.AllocaInsertPt = OldAllocaIP; }
1904     };
1905   };
1906 
1907 private:
1908   /// CXXThisDecl - When generating code for a C++ member function,
1909   /// this will hold the implicit 'this' declaration.
1910   ImplicitParamDecl *CXXABIThisDecl = nullptr;
1911   llvm::Value *CXXABIThisValue = nullptr;
1912   llvm::Value *CXXThisValue = nullptr;
1913   CharUnits CXXABIThisAlignment;
1914   CharUnits CXXThisAlignment;
1915 
1916   /// The value of 'this' to use when evaluating CXXDefaultInitExprs within
1917   /// this expression.
1918   Address CXXDefaultInitExprThis = Address::invalid();
1919 
1920   /// The current array initialization index when evaluating an
1921   /// ArrayInitIndexExpr within an ArrayInitLoopExpr.
1922   llvm::Value *ArrayInitIndex = nullptr;
1923 
1924   /// The values of function arguments to use when evaluating
1925   /// CXXInheritedCtorInitExprs within this context.
1926   CallArgList CXXInheritedCtorInitExprArgs;
1927 
1928   /// CXXStructorImplicitParamDecl - When generating code for a constructor or
1929   /// destructor, this will hold the implicit argument (e.g. VTT).
1930   ImplicitParamDecl *CXXStructorImplicitParamDecl = nullptr;
1931   llvm::Value *CXXStructorImplicitParamValue = nullptr;
1932 
1933   /// OutermostConditional - Points to the outermost active
1934   /// conditional control.  This is used so that we know if a
1935   /// temporary should be destroyed conditionally.
1936   ConditionalEvaluation *OutermostConditional = nullptr;
1937 
1938   /// The current lexical scope.
1939   LexicalScope *CurLexicalScope = nullptr;
1940 
1941   /// The current source location that should be used for exception
1942   /// handling code.
1943   SourceLocation CurEHLocation;
1944 
1945   /// BlockByrefInfos - For each __block variable, contains
1946   /// information about the layout of the variable.
1947   llvm::DenseMap<const ValueDecl *, BlockByrefInfo> BlockByrefInfos;
1948 
1949   /// Used by -fsanitize=nullability-return to determine whether the return
1950   /// value can be checked.
1951   llvm::Value *RetValNullabilityPrecondition = nullptr;
1952 
1953   /// Check if -fsanitize=nullability-return instrumentation is required for
1954   /// this function.
1955   bool requiresReturnValueNullabilityCheck() const {
1956     return RetValNullabilityPrecondition;
1957   }
1958 
1959   /// Used to store precise source locations for return statements by the
1960   /// runtime return value checks.
1961   Address ReturnLocation = Address::invalid();
1962 
1963   /// Check if the return value of this function requires sanitization.
1964   bool requiresReturnValueCheck() const;
1965 
1966   bool isInAllocaArgument(CGCXXABI &ABI, QualType Ty);
1967   bool hasInAllocaArg(const CXXMethodDecl *MD);
1968 
1969   llvm::BasicBlock *TerminateLandingPad = nullptr;
1970   llvm::BasicBlock *TerminateHandler = nullptr;
1971   llvm::SmallVector<llvm::BasicBlock *, 2> TrapBBs;
1972 
1973   /// Terminate funclets keyed by parent funclet pad.
1974   llvm::MapVector<llvm::Value *, llvm::BasicBlock *> TerminateFunclets;
1975 
1976   /// Largest vector width used in ths function. Will be used to create a
1977   /// function attribute.
1978   unsigned LargestVectorWidth = 0;
1979 
1980   /// True if we need emit the life-time markers. This is initially set in
1981   /// the constructor, but could be overwritten to true if this is a coroutine.
1982   bool ShouldEmitLifetimeMarkers;
1983 
1984   /// Add OpenCL kernel arg metadata and the kernel attribute metadata to
1985   /// the function metadata.
1986   void EmitKernelMetadata(const FunctionDecl *FD, llvm::Function *Fn);
1987 
1988 public:
1989   CodeGenFunction(CodeGenModule &cgm, bool suppressNewContext=false);
1990   ~CodeGenFunction();
1991 
1992   CodeGenTypes &getTypes() const { return CGM.getTypes(); }
1993   ASTContext &getContext() const { return CGM.getContext(); }
1994   CGDebugInfo *getDebugInfo() {
1995     if (DisableDebugInfo)
1996       return nullptr;
1997     return DebugInfo;
1998   }
1999   void disableDebugInfo() { DisableDebugInfo = true; }
2000   void enableDebugInfo() { DisableDebugInfo = false; }
2001 
2002   bool shouldUseFusedARCCalls() {
2003     return CGM.getCodeGenOpts().OptimizationLevel == 0;
2004   }
2005 
2006   const LangOptions &getLangOpts() const { return CGM.getLangOpts(); }
2007 
2008   /// Returns a pointer to the function's exception object and selector slot,
2009   /// which is assigned in every landing pad.
2010   Address getExceptionSlot();
2011   Address getEHSelectorSlot();
2012 
2013   /// Returns the contents of the function's exception object and selector
2014   /// slots.
2015   llvm::Value *getExceptionFromSlot();
2016   llvm::Value *getSelectorFromSlot();
2017 
2018   Address getNormalCleanupDestSlot();
2019 
2020   llvm::BasicBlock *getUnreachableBlock() {
2021     if (!UnreachableBlock) {
2022       UnreachableBlock = createBasicBlock("unreachable");
2023       new llvm::UnreachableInst(getLLVMContext(), UnreachableBlock);
2024     }
2025     return UnreachableBlock;
2026   }
2027 
2028   llvm::BasicBlock *getInvokeDest() {
2029     if (!EHStack.requiresLandingPad()) return nullptr;
2030     return getInvokeDestImpl();
2031   }
2032 
2033   bool currentFunctionUsesSEHTry() const { return !!CurSEHParent; }
2034 
2035   const TargetInfo &getTarget() const { return Target; }
2036   llvm::LLVMContext &getLLVMContext() { return CGM.getLLVMContext(); }
2037   const TargetCodeGenInfo &getTargetHooks() const {
2038     return CGM.getTargetCodeGenInfo();
2039   }
2040 
2041   //===--------------------------------------------------------------------===//
2042   //                                  Cleanups
2043   //===--------------------------------------------------------------------===//
2044 
2045   typedef void Destroyer(CodeGenFunction &CGF, Address addr, QualType ty);
2046 
2047   void pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
2048                                         Address arrayEndPointer,
2049                                         QualType elementType,
2050                                         CharUnits elementAlignment,
2051                                         Destroyer *destroyer);
2052   void pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
2053                                       llvm::Value *arrayEnd,
2054                                       QualType elementType,
2055                                       CharUnits elementAlignment,
2056                                       Destroyer *destroyer);
2057 
2058   void pushDestroy(QualType::DestructionKind dtorKind,
2059                    Address addr, QualType type);
2060   void pushEHDestroy(QualType::DestructionKind dtorKind,
2061                      Address addr, QualType type);
2062   void pushDestroy(CleanupKind kind, Address addr, QualType type,
2063                    Destroyer *destroyer, bool useEHCleanupForArray);
2064   void pushLifetimeExtendedDestroy(CleanupKind kind, Address addr,
2065                                    QualType type, Destroyer *destroyer,
2066                                    bool useEHCleanupForArray);
2067   void pushCallObjectDeleteCleanup(const FunctionDecl *OperatorDelete,
2068                                    llvm::Value *CompletePtr,
2069                                    QualType ElementType);
2070   void pushStackRestore(CleanupKind kind, Address SPMem);
2071   void pushKmpcAllocFree(CleanupKind Kind,
2072                          std::pair<llvm::Value *, llvm::Value *> AddrSizePair);
2073   void emitDestroy(Address addr, QualType type, Destroyer *destroyer,
2074                    bool useEHCleanupForArray);
2075   llvm::Function *generateDestroyHelper(Address addr, QualType type,
2076                                         Destroyer *destroyer,
2077                                         bool useEHCleanupForArray,
2078                                         const VarDecl *VD);
2079   void emitArrayDestroy(llvm::Value *begin, llvm::Value *end,
2080                         QualType elementType, CharUnits elementAlign,
2081                         Destroyer *destroyer,
2082                         bool checkZeroLength, bool useEHCleanup);
2083 
2084   Destroyer *getDestroyer(QualType::DestructionKind destructionKind);
2085 
2086   /// Determines whether an EH cleanup is required to destroy a type
2087   /// with the given destruction kind.
2088   bool needsEHCleanup(QualType::DestructionKind kind) {
2089     switch (kind) {
2090     case QualType::DK_none:
2091       return false;
2092     case QualType::DK_cxx_destructor:
2093     case QualType::DK_objc_weak_lifetime:
2094     case QualType::DK_nontrivial_c_struct:
2095       return getLangOpts().Exceptions;
2096     case QualType::DK_objc_strong_lifetime:
2097       return getLangOpts().Exceptions &&
2098              CGM.getCodeGenOpts().ObjCAutoRefCountExceptions;
2099     }
2100     llvm_unreachable("bad destruction kind");
2101   }
2102 
2103   CleanupKind getCleanupKind(QualType::DestructionKind kind) {
2104     return (needsEHCleanup(kind) ? NormalAndEHCleanup : NormalCleanup);
2105   }
2106 
2107   //===--------------------------------------------------------------------===//
2108   //                                  Objective-C
2109   //===--------------------------------------------------------------------===//
2110 
2111   void GenerateObjCMethod(const ObjCMethodDecl *OMD);
2112 
2113   void StartObjCMethod(const ObjCMethodDecl *MD, const ObjCContainerDecl *CD);
2114 
2115   /// GenerateObjCGetter - Synthesize an Objective-C property getter function.
2116   void GenerateObjCGetter(ObjCImplementationDecl *IMP,
2117                           const ObjCPropertyImplDecl *PID);
2118   void generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
2119                               const ObjCPropertyImplDecl *propImpl,
2120                               const ObjCMethodDecl *GetterMothodDecl,
2121                               llvm::Constant *AtomicHelperFn);
2122 
2123   void GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
2124                                   ObjCMethodDecl *MD, bool ctor);
2125 
2126   /// GenerateObjCSetter - Synthesize an Objective-C property setter function
2127   /// for the given property.
2128   void GenerateObjCSetter(ObjCImplementationDecl *IMP,
2129                           const ObjCPropertyImplDecl *PID);
2130   void generateObjCSetterBody(const ObjCImplementationDecl *classImpl,
2131                               const ObjCPropertyImplDecl *propImpl,
2132                               llvm::Constant *AtomicHelperFn);
2133 
2134   //===--------------------------------------------------------------------===//
2135   //                                  Block Bits
2136   //===--------------------------------------------------------------------===//
2137 
2138   /// Emit block literal.
2139   /// \return an LLVM value which is a pointer to a struct which contains
2140   /// information about the block, including the block invoke function, the
2141   /// captured variables, etc.
2142   llvm::Value *EmitBlockLiteral(const BlockExpr *);
2143 
2144   llvm::Function *GenerateBlockFunction(GlobalDecl GD,
2145                                         const CGBlockInfo &Info,
2146                                         const DeclMapTy &ldm,
2147                                         bool IsLambdaConversionToBlock,
2148                                         bool BuildGlobalBlock);
2149 
2150   /// Check if \p T is a C++ class that has a destructor that can throw.
2151   static bool cxxDestructorCanThrow(QualType T);
2152 
2153   llvm::Constant *GenerateCopyHelperFunction(const CGBlockInfo &blockInfo);
2154   llvm::Constant *GenerateDestroyHelperFunction(const CGBlockInfo &blockInfo);
2155   llvm::Constant *GenerateObjCAtomicSetterCopyHelperFunction(
2156                                              const ObjCPropertyImplDecl *PID);
2157   llvm::Constant *GenerateObjCAtomicGetterCopyHelperFunction(
2158                                              const ObjCPropertyImplDecl *PID);
2159   llvm::Value *EmitBlockCopyAndAutorelease(llvm::Value *Block, QualType Ty);
2160 
2161   void BuildBlockRelease(llvm::Value *DeclPtr, BlockFieldFlags flags,
2162                          bool CanThrow);
2163 
2164   class AutoVarEmission;
2165 
2166   void emitByrefStructureInit(const AutoVarEmission &emission);
2167 
2168   /// Enter a cleanup to destroy a __block variable.  Note that this
2169   /// cleanup should be a no-op if the variable hasn't left the stack
2170   /// yet; if a cleanup is required for the variable itself, that needs
2171   /// to be done externally.
2172   ///
2173   /// \param Kind Cleanup kind.
2174   ///
2175   /// \param Addr When \p LoadBlockVarAddr is false, the address of the __block
2176   /// structure that will be passed to _Block_object_dispose. When
2177   /// \p LoadBlockVarAddr is true, the address of the field of the block
2178   /// structure that holds the address of the __block structure.
2179   ///
2180   /// \param Flags The flag that will be passed to _Block_object_dispose.
2181   ///
2182   /// \param LoadBlockVarAddr Indicates whether we need to emit a load from
2183   /// \p Addr to get the address of the __block structure.
2184   void enterByrefCleanup(CleanupKind Kind, Address Addr, BlockFieldFlags Flags,
2185                          bool LoadBlockVarAddr, bool CanThrow);
2186 
2187   void setBlockContextParameter(const ImplicitParamDecl *D, unsigned argNum,
2188                                 llvm::Value *ptr);
2189 
2190   Address LoadBlockStruct();
2191   Address GetAddrOfBlockDecl(const VarDecl *var);
2192 
2193   /// BuildBlockByrefAddress - Computes the location of the
2194   /// data in a variable which is declared as __block.
2195   Address emitBlockByrefAddress(Address baseAddr, const VarDecl *V,
2196                                 bool followForward = true);
2197   Address emitBlockByrefAddress(Address baseAddr,
2198                                 const BlockByrefInfo &info,
2199                                 bool followForward,
2200                                 const llvm::Twine &name);
2201 
2202   const BlockByrefInfo &getBlockByrefInfo(const VarDecl *var);
2203 
2204   QualType BuildFunctionArgList(GlobalDecl GD, FunctionArgList &Args);
2205 
2206   void GenerateCode(GlobalDecl GD, llvm::Function *Fn,
2207                     const CGFunctionInfo &FnInfo);
2208 
2209   /// Annotate the function with an attribute that disables TSan checking at
2210   /// runtime.
2211   void markAsIgnoreThreadCheckingAtRuntime(llvm::Function *Fn);
2212 
2213   /// Emit code for the start of a function.
2214   /// \param Loc       The location to be associated with the function.
2215   /// \param StartLoc  The location of the function body.
2216   void StartFunction(GlobalDecl GD,
2217                      QualType RetTy,
2218                      llvm::Function *Fn,
2219                      const CGFunctionInfo &FnInfo,
2220                      const FunctionArgList &Args,
2221                      SourceLocation Loc = SourceLocation(),
2222                      SourceLocation StartLoc = SourceLocation());
2223 
2224   static bool IsConstructorDelegationValid(const CXXConstructorDecl *Ctor);
2225 
2226   void EmitConstructorBody(FunctionArgList &Args);
2227   void EmitDestructorBody(FunctionArgList &Args);
2228   void emitImplicitAssignmentOperatorBody(FunctionArgList &Args);
2229   void EmitFunctionBody(const Stmt *Body);
2230   void EmitBlockWithFallThrough(llvm::BasicBlock *BB, const Stmt *S);
2231 
2232   void EmitForwardingCallToLambda(const CXXMethodDecl *LambdaCallOperator,
2233                                   CallArgList &CallArgs,
2234                                   const CGFunctionInfo *CallOpFnInfo = nullptr,
2235                                   llvm::Constant *CallOpFn = nullptr);
2236   void EmitLambdaBlockInvokeBody();
2237   void EmitLambdaStaticInvokeBody(const CXXMethodDecl *MD);
2238   void EmitLambdaDelegatingInvokeBody(const CXXMethodDecl *MD,
2239                                       CallArgList &CallArgs);
2240   void EmitLambdaInAllocaImplFn(const CXXMethodDecl *CallOp,
2241                                 const CGFunctionInfo **ImplFnInfo,
2242                                 llvm::Function **ImplFn);
2243   void EmitLambdaInAllocaCallOpBody(const CXXMethodDecl *MD);
2244   void EmitLambdaVLACapture(const VariableArrayType *VAT, LValue LV) {
2245     EmitStoreThroughLValue(RValue::get(VLASizeMap[VAT->getSizeExpr()]), LV);
2246   }
2247   void EmitAsanPrologueOrEpilogue(bool Prologue);
2248 
2249   /// Emit the unified return block, trying to avoid its emission when
2250   /// possible.
2251   /// \return The debug location of the user written return statement if the
2252   /// return block is avoided.
2253   llvm::DebugLoc EmitReturnBlock();
2254 
2255   /// FinishFunction - Complete IR generation of the current function. It is
2256   /// legal to call this function even if there is no current insertion point.
2257   void FinishFunction(SourceLocation EndLoc=SourceLocation());
2258 
2259   void StartThunk(llvm::Function *Fn, GlobalDecl GD,
2260                   const CGFunctionInfo &FnInfo, bool IsUnprototyped);
2261 
2262   void EmitCallAndReturnForThunk(llvm::FunctionCallee Callee,
2263                                  const ThunkInfo *Thunk, bool IsUnprototyped);
2264 
2265   void FinishThunk();
2266 
2267   /// Emit a musttail call for a thunk with a potentially adjusted this pointer.
2268   void EmitMustTailThunk(GlobalDecl GD, llvm::Value *AdjustedThisPtr,
2269                          llvm::FunctionCallee Callee);
2270 
2271   /// Generate a thunk for the given method.
2272   void generateThunk(llvm::Function *Fn, const CGFunctionInfo &FnInfo,
2273                      GlobalDecl GD, const ThunkInfo &Thunk,
2274                      bool IsUnprototyped);
2275 
2276   llvm::Function *GenerateVarArgsThunk(llvm::Function *Fn,
2277                                        const CGFunctionInfo &FnInfo,
2278                                        GlobalDecl GD, const ThunkInfo &Thunk);
2279 
2280   void EmitCtorPrologue(const CXXConstructorDecl *CD, CXXCtorType Type,
2281                         FunctionArgList &Args);
2282 
2283   void EmitInitializerForField(FieldDecl *Field, LValue LHS, Expr *Init);
2284 
2285   /// Struct with all information about dynamic [sub]class needed to set vptr.
2286   struct VPtr {
2287     BaseSubobject Base;
2288     const CXXRecordDecl *NearestVBase;
2289     CharUnits OffsetFromNearestVBase;
2290     const CXXRecordDecl *VTableClass;
2291   };
2292 
2293   /// Initialize the vtable pointer of the given subobject.
2294   void InitializeVTablePointer(const VPtr &vptr);
2295 
2296   typedef llvm::SmallVector<VPtr, 4> VPtrsVector;
2297 
2298   typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
2299   VPtrsVector getVTablePointers(const CXXRecordDecl *VTableClass);
2300 
2301   void getVTablePointers(BaseSubobject Base, const CXXRecordDecl *NearestVBase,
2302                          CharUnits OffsetFromNearestVBase,
2303                          bool BaseIsNonVirtualPrimaryBase,
2304                          const CXXRecordDecl *VTableClass,
2305                          VisitedVirtualBasesSetTy &VBases, VPtrsVector &vptrs);
2306 
2307   void InitializeVTablePointers(const CXXRecordDecl *ClassDecl);
2308 
2309   /// GetVTablePtr - Return the Value of the vtable pointer member pointed
2310   /// to by This.
2311   llvm::Value *GetVTablePtr(Address This, llvm::Type *VTableTy,
2312                             const CXXRecordDecl *VTableClass);
2313 
2314   enum CFITypeCheckKind {
2315     CFITCK_VCall,
2316     CFITCK_NVCall,
2317     CFITCK_DerivedCast,
2318     CFITCK_UnrelatedCast,
2319     CFITCK_ICall,
2320     CFITCK_NVMFCall,
2321     CFITCK_VMFCall,
2322   };
2323 
2324   /// Derived is the presumed address of an object of type T after a
2325   /// cast. If T is a polymorphic class type, emit a check that the virtual
2326   /// table for Derived belongs to a class derived from T.
2327   void EmitVTablePtrCheckForCast(QualType T, Address Derived, bool MayBeNull,
2328                                  CFITypeCheckKind TCK, SourceLocation Loc);
2329 
2330   /// EmitVTablePtrCheckForCall - Virtual method MD is being called via VTable.
2331   /// If vptr CFI is enabled, emit a check that VTable is valid.
2332   void EmitVTablePtrCheckForCall(const CXXRecordDecl *RD, llvm::Value *VTable,
2333                                  CFITypeCheckKind TCK, SourceLocation Loc);
2334 
2335   /// EmitVTablePtrCheck - Emit a check that VTable is a valid virtual table for
2336   /// RD using llvm.type.test.
2337   void EmitVTablePtrCheck(const CXXRecordDecl *RD, llvm::Value *VTable,
2338                           CFITypeCheckKind TCK, SourceLocation Loc);
2339 
2340   /// If whole-program virtual table optimization is enabled, emit an assumption
2341   /// that VTable is a member of RD's type identifier. Or, if vptr CFI is
2342   /// enabled, emit a check that VTable is a member of RD's type identifier.
2343   void EmitTypeMetadataCodeForVCall(const CXXRecordDecl *RD,
2344                                     llvm::Value *VTable, SourceLocation Loc);
2345 
2346   /// Returns whether we should perform a type checked load when loading a
2347   /// virtual function for virtual calls to members of RD. This is generally
2348   /// true when both vcall CFI and whole-program-vtables are enabled.
2349   bool ShouldEmitVTableTypeCheckedLoad(const CXXRecordDecl *RD);
2350 
2351   /// Emit a type checked load from the given vtable.
2352   llvm::Value *EmitVTableTypeCheckedLoad(const CXXRecordDecl *RD,
2353                                          llvm::Value *VTable,
2354                                          llvm::Type *VTableTy,
2355                                          uint64_t VTableByteOffset);
2356 
2357   /// EnterDtorCleanups - Enter the cleanups necessary to complete the
2358   /// given phase of destruction for a destructor.  The end result
2359   /// should call destructors on members and base classes in reverse
2360   /// order of their construction.
2361   void EnterDtorCleanups(const CXXDestructorDecl *Dtor, CXXDtorType Type);
2362 
2363   /// ShouldInstrumentFunction - Return true if the current function should be
2364   /// instrumented with __cyg_profile_func_* calls
2365   bool ShouldInstrumentFunction();
2366 
2367   /// ShouldSkipSanitizerInstrumentation - Return true if the current function
2368   /// should not be instrumented with sanitizers.
2369   bool ShouldSkipSanitizerInstrumentation();
2370 
2371   /// ShouldXRayInstrument - Return true if the current function should be
2372   /// instrumented with XRay nop sleds.
2373   bool ShouldXRayInstrumentFunction() const;
2374 
2375   /// AlwaysEmitXRayCustomEvents - Return true if we must unconditionally emit
2376   /// XRay custom event handling calls.
2377   bool AlwaysEmitXRayCustomEvents() const;
2378 
2379   /// AlwaysEmitXRayTypedEvents - Return true if clang must unconditionally emit
2380   /// XRay typed event handling calls.
2381   bool AlwaysEmitXRayTypedEvents() const;
2382 
2383   /// Return a type hash constant for a function instrumented by
2384   /// -fsanitize=function.
2385   llvm::ConstantInt *getUBSanFunctionTypeHash(QualType T) const;
2386 
2387   /// EmitFunctionProlog - Emit the target specific LLVM code to load the
2388   /// arguments for the given function. This is also responsible for naming the
2389   /// LLVM function arguments.
2390   void EmitFunctionProlog(const CGFunctionInfo &FI,
2391                           llvm::Function *Fn,
2392                           const FunctionArgList &Args);
2393 
2394   /// EmitFunctionEpilog - Emit the target specific LLVM code to return the
2395   /// given temporary.
2396   void EmitFunctionEpilog(const CGFunctionInfo &FI, bool EmitRetDbgLoc,
2397                           SourceLocation EndLoc);
2398 
2399   /// Emit a test that checks if the return value \p RV is nonnull.
2400   void EmitReturnValueCheck(llvm::Value *RV);
2401 
2402   /// EmitStartEHSpec - Emit the start of the exception spec.
2403   void EmitStartEHSpec(const Decl *D);
2404 
2405   /// EmitEndEHSpec - Emit the end of the exception spec.
2406   void EmitEndEHSpec(const Decl *D);
2407 
2408   /// getTerminateLandingPad - Return a landing pad that just calls terminate.
2409   llvm::BasicBlock *getTerminateLandingPad();
2410 
2411   /// getTerminateLandingPad - Return a cleanup funclet that just calls
2412   /// terminate.
2413   llvm::BasicBlock *getTerminateFunclet();
2414 
2415   /// getTerminateHandler - Return a handler (not a landing pad, just
2416   /// a catch handler) that just calls terminate.  This is used when
2417   /// a terminate scope encloses a try.
2418   llvm::BasicBlock *getTerminateHandler();
2419 
2420   llvm::Type *ConvertTypeForMem(QualType T);
2421   llvm::Type *ConvertType(QualType T);
2422   llvm::Type *ConvertType(const TypeDecl *T) {
2423     return ConvertType(getContext().getTypeDeclType(T));
2424   }
2425 
2426   /// LoadObjCSelf - Load the value of self. This function is only valid while
2427   /// generating code for an Objective-C method.
2428   llvm::Value *LoadObjCSelf();
2429 
2430   /// TypeOfSelfObject - Return type of object that this self represents.
2431   QualType TypeOfSelfObject();
2432 
2433   /// getEvaluationKind - Return the TypeEvaluationKind of QualType \c T.
2434   static TypeEvaluationKind getEvaluationKind(QualType T);
2435 
2436   static bool hasScalarEvaluationKind(QualType T) {
2437     return getEvaluationKind(T) == TEK_Scalar;
2438   }
2439 
2440   static bool hasAggregateEvaluationKind(QualType T) {
2441     return getEvaluationKind(T) == TEK_Aggregate;
2442   }
2443 
2444   /// createBasicBlock - Create an LLVM basic block.
2445   llvm::BasicBlock *createBasicBlock(const Twine &name = "",
2446                                      llvm::Function *parent = nullptr,
2447                                      llvm::BasicBlock *before = nullptr) {
2448     return llvm::BasicBlock::Create(getLLVMContext(), name, parent, before);
2449   }
2450 
2451   /// getBasicBlockForLabel - Return the LLVM basicblock that the specified
2452   /// label maps to.
2453   JumpDest getJumpDestForLabel(const LabelDecl *S);
2454 
2455   /// SimplifyForwardingBlocks - If the given basic block is only a branch to
2456   /// another basic block, simplify it. This assumes that no other code could
2457   /// potentially reference the basic block.
2458   void SimplifyForwardingBlocks(llvm::BasicBlock *BB);
2459 
2460   /// EmitBlock - Emit the given block \arg BB and set it as the insert point,
2461   /// adding a fall-through branch from the current insert block if
2462   /// necessary. It is legal to call this function even if there is no current
2463   /// insertion point.
2464   ///
2465   /// IsFinished - If true, indicates that the caller has finished emitting
2466   /// branches to the given block and does not expect to emit code into it. This
2467   /// means the block can be ignored if it is unreachable.
2468   void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false);
2469 
2470   /// EmitBlockAfterUses - Emit the given block somewhere hopefully
2471   /// near its uses, and leave the insertion point in it.
2472   void EmitBlockAfterUses(llvm::BasicBlock *BB);
2473 
2474   /// EmitBranch - Emit a branch to the specified basic block from the current
2475   /// insert block, taking care to avoid creation of branches from dummy
2476   /// blocks. It is legal to call this function even if there is no current
2477   /// insertion point.
2478   ///
2479   /// This function clears the current insertion point. The caller should follow
2480   /// calls to this function with calls to Emit*Block prior to generation new
2481   /// code.
2482   void EmitBranch(llvm::BasicBlock *Block);
2483 
2484   /// HaveInsertPoint - True if an insertion point is defined. If not, this
2485   /// indicates that the current code being emitted is unreachable.
2486   bool HaveInsertPoint() const {
2487     return Builder.GetInsertBlock() != nullptr;
2488   }
2489 
2490   /// EnsureInsertPoint - Ensure that an insertion point is defined so that
2491   /// emitted IR has a place to go. Note that by definition, if this function
2492   /// creates a block then that block is unreachable; callers may do better to
2493   /// detect when no insertion point is defined and simply skip IR generation.
2494   void EnsureInsertPoint() {
2495     if (!HaveInsertPoint())
2496       EmitBlock(createBasicBlock());
2497   }
2498 
2499   /// ErrorUnsupported - Print out an error that codegen doesn't support the
2500   /// specified stmt yet.
2501   void ErrorUnsupported(const Stmt *S, const char *Type);
2502 
2503   //===--------------------------------------------------------------------===//
2504   //                                  Helpers
2505   //===--------------------------------------------------------------------===//
2506 
2507   LValue MakeAddrLValue(Address Addr, QualType T,
2508                         AlignmentSource Source = AlignmentSource::Type) {
2509     return LValue::MakeAddr(Addr, T, getContext(), LValueBaseInfo(Source),
2510                             CGM.getTBAAAccessInfo(T));
2511   }
2512 
2513   LValue MakeAddrLValue(Address Addr, QualType T, LValueBaseInfo BaseInfo,
2514                         TBAAAccessInfo TBAAInfo) {
2515     return LValue::MakeAddr(Addr, T, getContext(), BaseInfo, TBAAInfo);
2516   }
2517 
2518   LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment,
2519                         AlignmentSource Source = AlignmentSource::Type) {
2520     Address Addr(V, ConvertTypeForMem(T), Alignment);
2521     return LValue::MakeAddr(Addr, T, getContext(), LValueBaseInfo(Source),
2522                             CGM.getTBAAAccessInfo(T));
2523   }
2524 
2525   LValue
2526   MakeAddrLValueWithoutTBAA(Address Addr, QualType T,
2527                             AlignmentSource Source = AlignmentSource::Type) {
2528     return LValue::MakeAddr(Addr, T, getContext(), LValueBaseInfo(Source),
2529                             TBAAAccessInfo());
2530   }
2531 
2532   LValue MakeNaturalAlignPointeeAddrLValue(llvm::Value *V, QualType T);
2533   LValue MakeNaturalAlignAddrLValue(llvm::Value *V, QualType T);
2534 
2535   Address EmitLoadOfReference(LValue RefLVal,
2536                               LValueBaseInfo *PointeeBaseInfo = nullptr,
2537                               TBAAAccessInfo *PointeeTBAAInfo = nullptr);
2538   LValue EmitLoadOfReferenceLValue(LValue RefLVal);
2539   LValue EmitLoadOfReferenceLValue(Address RefAddr, QualType RefTy,
2540                                    AlignmentSource Source =
2541                                        AlignmentSource::Type) {
2542     LValue RefLVal = MakeAddrLValue(RefAddr, RefTy, LValueBaseInfo(Source),
2543                                     CGM.getTBAAAccessInfo(RefTy));
2544     return EmitLoadOfReferenceLValue(RefLVal);
2545   }
2546 
2547   /// Load a pointer with type \p PtrTy stored at address \p Ptr.
2548   /// Note that \p PtrTy is the type of the loaded pointer, not the addresses
2549   /// it is loaded from.
2550   Address EmitLoadOfPointer(Address Ptr, const PointerType *PtrTy,
2551                             LValueBaseInfo *BaseInfo = nullptr,
2552                             TBAAAccessInfo *TBAAInfo = nullptr);
2553   LValue EmitLoadOfPointerLValue(Address Ptr, const PointerType *PtrTy);
2554 
2555   /// CreateTempAlloca - This creates an alloca and inserts it into the entry
2556   /// block if \p ArraySize is nullptr, otherwise inserts it at the current
2557   /// insertion point of the builder. The caller is responsible for setting an
2558   /// appropriate alignment on
2559   /// the alloca.
2560   ///
2561   /// \p ArraySize is the number of array elements to be allocated if it
2562   ///    is not nullptr.
2563   ///
2564   /// LangAS::Default is the address space of pointers to local variables and
2565   /// temporaries, as exposed in the source language. In certain
2566   /// configurations, this is not the same as the alloca address space, and a
2567   /// cast is needed to lift the pointer from the alloca AS into
2568   /// LangAS::Default. This can happen when the target uses a restricted
2569   /// address space for the stack but the source language requires
2570   /// LangAS::Default to be a generic address space. The latter condition is
2571   /// common for most programming languages; OpenCL is an exception in that
2572   /// LangAS::Default is the private address space, which naturally maps
2573   /// to the stack.
2574   ///
2575   /// Because the address of a temporary is often exposed to the program in
2576   /// various ways, this function will perform the cast. The original alloca
2577   /// instruction is returned through \p Alloca if it is not nullptr.
2578   ///
2579   /// The cast is not performaed in CreateTempAllocaWithoutCast. This is
2580   /// more efficient if the caller knows that the address will not be exposed.
2581   llvm::AllocaInst *CreateTempAlloca(llvm::Type *Ty, const Twine &Name = "tmp",
2582                                      llvm::Value *ArraySize = nullptr);
2583   Address CreateTempAlloca(llvm::Type *Ty, CharUnits align,
2584                            const Twine &Name = "tmp",
2585                            llvm::Value *ArraySize = nullptr,
2586                            Address *Alloca = nullptr);
2587   Address CreateTempAllocaWithoutCast(llvm::Type *Ty, CharUnits align,
2588                                       const Twine &Name = "tmp",
2589                                       llvm::Value *ArraySize = nullptr);
2590 
2591   /// CreateDefaultAlignedTempAlloca - This creates an alloca with the
2592   /// default ABI alignment of the given LLVM type.
2593   ///
2594   /// IMPORTANT NOTE: This is *not* generally the right alignment for
2595   /// any given AST type that happens to have been lowered to the
2596   /// given IR type.  This should only ever be used for function-local,
2597   /// IR-driven manipulations like saving and restoring a value.  Do
2598   /// not hand this address off to arbitrary IRGen routines, and especially
2599   /// do not pass it as an argument to a function that might expect a
2600   /// properly ABI-aligned value.
2601   Address CreateDefaultAlignTempAlloca(llvm::Type *Ty,
2602                                        const Twine &Name = "tmp");
2603 
2604   /// CreateIRTemp - Create a temporary IR object of the given type, with
2605   /// appropriate alignment. This routine should only be used when an temporary
2606   /// value needs to be stored into an alloca (for example, to avoid explicit
2607   /// PHI construction), but the type is the IR type, not the type appropriate
2608   /// for storing in memory.
2609   ///
2610   /// That is, this is exactly equivalent to CreateMemTemp, but calling
2611   /// ConvertType instead of ConvertTypeForMem.
2612   Address CreateIRTemp(QualType T, const Twine &Name = "tmp");
2613 
2614   /// CreateMemTemp - Create a temporary memory object of the given type, with
2615   /// appropriate alignmen and cast it to the default address space. Returns
2616   /// the original alloca instruction by \p Alloca if it is not nullptr.
2617   Address CreateMemTemp(QualType T, const Twine &Name = "tmp",
2618                         Address *Alloca = nullptr);
2619   Address CreateMemTemp(QualType T, CharUnits Align, const Twine &Name = "tmp",
2620                         Address *Alloca = nullptr);
2621 
2622   /// CreateMemTemp - Create a temporary memory object of the given type, with
2623   /// appropriate alignmen without casting it to the default address space.
2624   Address CreateMemTempWithoutCast(QualType T, const Twine &Name = "tmp");
2625   Address CreateMemTempWithoutCast(QualType T, CharUnits Align,
2626                                    const Twine &Name = "tmp");
2627 
2628   /// CreateAggTemp - Create a temporary memory object for the given
2629   /// aggregate type.
2630   AggValueSlot CreateAggTemp(QualType T, const Twine &Name = "tmp",
2631                              Address *Alloca = nullptr) {
2632     return AggValueSlot::forAddr(CreateMemTemp(T, Name, Alloca),
2633                                  T.getQualifiers(),
2634                                  AggValueSlot::IsNotDestructed,
2635                                  AggValueSlot::DoesNotNeedGCBarriers,
2636                                  AggValueSlot::IsNotAliased,
2637                                  AggValueSlot::DoesNotOverlap);
2638   }
2639 
2640   /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
2641   /// expression and compare the result against zero, returning an Int1Ty value.
2642   llvm::Value *EvaluateExprAsBool(const Expr *E);
2643 
2644   /// EmitIgnoredExpr - Emit an expression in a context which ignores the result.
2645   void EmitIgnoredExpr(const Expr *E);
2646 
2647   /// EmitAnyExpr - Emit code to compute the specified expression which can have
2648   /// any type.  The result is returned as an RValue struct.  If this is an
2649   /// aggregate expression, the aggloc/agglocvolatile arguments indicate where
2650   /// the result should be returned.
2651   ///
2652   /// \param ignoreResult True if the resulting value isn't used.
2653   RValue EmitAnyExpr(const Expr *E,
2654                      AggValueSlot aggSlot = AggValueSlot::ignored(),
2655                      bool ignoreResult = false);
2656 
2657   // EmitVAListRef - Emit a "reference" to a va_list; this is either the address
2658   // or the value of the expression, depending on how va_list is defined.
2659   Address EmitVAListRef(const Expr *E);
2660 
2661   /// Emit a "reference" to a __builtin_ms_va_list; this is
2662   /// always the value of the expression, because a __builtin_ms_va_list is a
2663   /// pointer to a char.
2664   Address EmitMSVAListRef(const Expr *E);
2665 
2666   /// EmitAnyExprToTemp - Similarly to EmitAnyExpr(), however, the result will
2667   /// always be accessible even if no aggregate location is provided.
2668   RValue EmitAnyExprToTemp(const Expr *E);
2669 
2670   /// EmitAnyExprToMem - Emits the code necessary to evaluate an
2671   /// arbitrary expression into the given memory location.
2672   void EmitAnyExprToMem(const Expr *E, Address Location,
2673                         Qualifiers Quals, bool IsInitializer);
2674 
2675   void EmitAnyExprToExn(const Expr *E, Address Addr);
2676 
2677   /// EmitExprAsInit - Emits the code necessary to initialize a
2678   /// location in memory with the given initializer.
2679   void EmitExprAsInit(const Expr *init, const ValueDecl *D, LValue lvalue,
2680                       bool capturedByInit);
2681 
2682   /// hasVolatileMember - returns true if aggregate type has a volatile
2683   /// member.
2684   bool hasVolatileMember(QualType T) {
2685     if (const RecordType *RT = T->getAs<RecordType>()) {
2686       const RecordDecl *RD = cast<RecordDecl>(RT->getDecl());
2687       return RD->hasVolatileMember();
2688     }
2689     return false;
2690   }
2691 
2692   /// Determine whether a return value slot may overlap some other object.
2693   AggValueSlot::Overlap_t getOverlapForReturnValue() {
2694     // FIXME: Assuming no overlap here breaks guaranteed copy elision for base
2695     // class subobjects. These cases may need to be revisited depending on the
2696     // resolution of the relevant core issue.
2697     return AggValueSlot::DoesNotOverlap;
2698   }
2699 
2700   /// Determine whether a field initialization may overlap some other object.
2701   AggValueSlot::Overlap_t getOverlapForFieldInit(const FieldDecl *FD);
2702 
2703   /// Determine whether a base class initialization may overlap some other
2704   /// object.
2705   AggValueSlot::Overlap_t getOverlapForBaseInit(const CXXRecordDecl *RD,
2706                                                 const CXXRecordDecl *BaseRD,
2707                                                 bool IsVirtual);
2708 
2709   /// Emit an aggregate assignment.
2710   void EmitAggregateAssign(LValue Dest, LValue Src, QualType EltTy) {
2711     bool IsVolatile = hasVolatileMember(EltTy);
2712     EmitAggregateCopy(Dest, Src, EltTy, AggValueSlot::MayOverlap, IsVolatile);
2713   }
2714 
2715   void EmitAggregateCopyCtor(LValue Dest, LValue Src,
2716                              AggValueSlot::Overlap_t MayOverlap) {
2717     EmitAggregateCopy(Dest, Src, Src.getType(), MayOverlap);
2718   }
2719 
2720   /// EmitAggregateCopy - Emit an aggregate copy.
2721   ///
2722   /// \param isVolatile \c true iff either the source or the destination is
2723   ///        volatile.
2724   /// \param MayOverlap Whether the tail padding of the destination might be
2725   ///        occupied by some other object. More efficient code can often be
2726   ///        generated if not.
2727   void EmitAggregateCopy(LValue Dest, LValue Src, QualType EltTy,
2728                          AggValueSlot::Overlap_t MayOverlap,
2729                          bool isVolatile = false);
2730 
2731   /// GetAddrOfLocalVar - Return the address of a local variable.
2732   Address GetAddrOfLocalVar(const VarDecl *VD) {
2733     auto it = LocalDeclMap.find(VD);
2734     assert(it != LocalDeclMap.end() &&
2735            "Invalid argument to GetAddrOfLocalVar(), no decl!");
2736     return it->second;
2737   }
2738 
2739   /// Given an opaque value expression, return its LValue mapping if it exists,
2740   /// otherwise create one.
2741   LValue getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e);
2742 
2743   /// Given an opaque value expression, return its RValue mapping if it exists,
2744   /// otherwise create one.
2745   RValue getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e);
2746 
2747   /// Get the index of the current ArrayInitLoopExpr, if any.
2748   llvm::Value *getArrayInitIndex() { return ArrayInitIndex; }
2749 
2750   /// getAccessedFieldNo - Given an encoded value and a result number, return
2751   /// the input field number being accessed.
2752   static unsigned getAccessedFieldNo(unsigned Idx, const llvm::Constant *Elts);
2753 
2754   llvm::BlockAddress *GetAddrOfLabel(const LabelDecl *L);
2755   llvm::BasicBlock *GetIndirectGotoBlock();
2756 
2757   /// Check if \p E is a C++ "this" pointer wrapped in value-preserving casts.
2758   static bool IsWrappedCXXThis(const Expr *E);
2759 
2760   /// EmitNullInitialization - Generate code to set a value of the given type to
2761   /// null, If the type contains data member pointers, they will be initialized
2762   /// to -1 in accordance with the Itanium C++ ABI.
2763   void EmitNullInitialization(Address DestPtr, QualType Ty);
2764 
2765   /// Emits a call to an LLVM variable-argument intrinsic, either
2766   /// \c llvm.va_start or \c llvm.va_end.
2767   /// \param ArgValue A reference to the \c va_list as emitted by either
2768   /// \c EmitVAListRef or \c EmitMSVAListRef.
2769   /// \param IsStart If \c true, emits a call to \c llvm.va_start; otherwise,
2770   /// calls \c llvm.va_end.
2771   llvm::Value *EmitVAStartEnd(llvm::Value *ArgValue, bool IsStart);
2772 
2773   /// Generate code to get an argument from the passed in pointer
2774   /// and update it accordingly.
2775   /// \param VE The \c VAArgExpr for which to generate code.
2776   /// \param VAListAddr Receives a reference to the \c va_list as emitted by
2777   /// either \c EmitVAListRef or \c EmitMSVAListRef.
2778   /// \returns A pointer to the argument.
2779   // FIXME: We should be able to get rid of this method and use the va_arg
2780   // instruction in LLVM instead once it works well enough.
2781   Address EmitVAArg(VAArgExpr *VE, Address &VAListAddr);
2782 
2783   /// emitArrayLength - Compute the length of an array, even if it's a
2784   /// VLA, and drill down to the base element type.
2785   llvm::Value *emitArrayLength(const ArrayType *arrayType,
2786                                QualType &baseType,
2787                                Address &addr);
2788 
2789   /// EmitVLASize - Capture all the sizes for the VLA expressions in
2790   /// the given variably-modified type and store them in the VLASizeMap.
2791   ///
2792   /// This function can be called with a null (unreachable) insert point.
2793   void EmitVariablyModifiedType(QualType Ty);
2794 
2795   struct VlaSizePair {
2796     llvm::Value *NumElts;
2797     QualType Type;
2798 
2799     VlaSizePair(llvm::Value *NE, QualType T) : NumElts(NE), Type(T) {}
2800   };
2801 
2802   /// Return the number of elements for a single dimension
2803   /// for the given array type.
2804   VlaSizePair getVLAElements1D(const VariableArrayType *vla);
2805   VlaSizePair getVLAElements1D(QualType vla);
2806 
2807   /// Returns an LLVM value that corresponds to the size,
2808   /// in non-variably-sized elements, of a variable length array type,
2809   /// plus that largest non-variably-sized element type.  Assumes that
2810   /// the type has already been emitted with EmitVariablyModifiedType.
2811   VlaSizePair getVLASize(const VariableArrayType *vla);
2812   VlaSizePair getVLASize(QualType vla);
2813 
2814   /// LoadCXXThis - Load the value of 'this'. This function is only valid while
2815   /// generating code for an C++ member function.
2816   llvm::Value *LoadCXXThis() {
2817     assert(CXXThisValue && "no 'this' value for this function");
2818     return CXXThisValue;
2819   }
2820   Address LoadCXXThisAddress();
2821 
2822   /// LoadCXXVTT - Load the VTT parameter to base constructors/destructors have
2823   /// virtual bases.
2824   // FIXME: Every place that calls LoadCXXVTT is something
2825   // that needs to be abstracted properly.
2826   llvm::Value *LoadCXXVTT() {
2827     assert(CXXStructorImplicitParamValue && "no VTT value for this function");
2828     return CXXStructorImplicitParamValue;
2829   }
2830 
2831   /// GetAddressOfBaseOfCompleteClass - Convert the given pointer to a
2832   /// complete class to the given direct base.
2833   Address
2834   GetAddressOfDirectBaseInCompleteClass(Address Value,
2835                                         const CXXRecordDecl *Derived,
2836                                         const CXXRecordDecl *Base,
2837                                         bool BaseIsVirtual);
2838 
2839   static bool ShouldNullCheckClassCastValue(const CastExpr *Cast);
2840 
2841   /// GetAddressOfBaseClass - This function will add the necessary delta to the
2842   /// load of 'this' and returns address of the base class.
2843   Address GetAddressOfBaseClass(Address Value,
2844                                 const CXXRecordDecl *Derived,
2845                                 CastExpr::path_const_iterator PathBegin,
2846                                 CastExpr::path_const_iterator PathEnd,
2847                                 bool NullCheckValue, SourceLocation Loc);
2848 
2849   Address GetAddressOfDerivedClass(Address Value,
2850                                    const CXXRecordDecl *Derived,
2851                                    CastExpr::path_const_iterator PathBegin,
2852                                    CastExpr::path_const_iterator PathEnd,
2853                                    bool NullCheckValue);
2854 
2855   /// GetVTTParameter - Return the VTT parameter that should be passed to a
2856   /// base constructor/destructor with virtual bases.
2857   /// FIXME: VTTs are Itanium ABI-specific, so the definition should move
2858   /// to ItaniumCXXABI.cpp together with all the references to VTT.
2859   llvm::Value *GetVTTParameter(GlobalDecl GD, bool ForVirtualBase,
2860                                bool Delegating);
2861 
2862   void EmitDelegateCXXConstructorCall(const CXXConstructorDecl *Ctor,
2863                                       CXXCtorType CtorType,
2864                                       const FunctionArgList &Args,
2865                                       SourceLocation Loc);
2866   // It's important not to confuse this and the previous function. Delegating
2867   // constructors are the C++0x feature. The constructor delegate optimization
2868   // is used to reduce duplication in the base and complete consturctors where
2869   // they are substantially the same.
2870   void EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor,
2871                                         const FunctionArgList &Args);
2872 
2873   /// Emit a call to an inheriting constructor (that is, one that invokes a
2874   /// constructor inherited from a base class) by inlining its definition. This
2875   /// is necessary if the ABI does not support forwarding the arguments to the
2876   /// base class constructor (because they're variadic or similar).
2877   void EmitInlinedInheritingCXXConstructorCall(const CXXConstructorDecl *Ctor,
2878                                                CXXCtorType CtorType,
2879                                                bool ForVirtualBase,
2880                                                bool Delegating,
2881                                                CallArgList &Args);
2882 
2883   /// Emit a call to a constructor inherited from a base class, passing the
2884   /// current constructor's arguments along unmodified (without even making
2885   /// a copy).
2886   void EmitInheritedCXXConstructorCall(const CXXConstructorDecl *D,
2887                                        bool ForVirtualBase, Address This,
2888                                        bool InheritedFromVBase,
2889                                        const CXXInheritedCtorInitExpr *E);
2890 
2891   void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
2892                               bool ForVirtualBase, bool Delegating,
2893                               AggValueSlot ThisAVS, const CXXConstructExpr *E);
2894 
2895   void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
2896                               bool ForVirtualBase, bool Delegating,
2897                               Address This, CallArgList &Args,
2898                               AggValueSlot::Overlap_t Overlap,
2899                               SourceLocation Loc, bool NewPointerIsChecked);
2900 
2901   /// Emit assumption load for all bases. Requires to be called only on
2902   /// most-derived class and not under construction of the object.
2903   void EmitVTableAssumptionLoads(const CXXRecordDecl *ClassDecl, Address This);
2904 
2905   /// Emit assumption that vptr load == global vtable.
2906   void EmitVTableAssumptionLoad(const VPtr &vptr, Address This);
2907 
2908   void EmitSynthesizedCXXCopyCtorCall(const CXXConstructorDecl *D,
2909                                       Address This, Address Src,
2910                                       const CXXConstructExpr *E);
2911 
2912   void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
2913                                   const ArrayType *ArrayTy,
2914                                   Address ArrayPtr,
2915                                   const CXXConstructExpr *E,
2916                                   bool NewPointerIsChecked,
2917                                   bool ZeroInitialization = false);
2918 
2919   void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
2920                                   llvm::Value *NumElements,
2921                                   Address ArrayPtr,
2922                                   const CXXConstructExpr *E,
2923                                   bool NewPointerIsChecked,
2924                                   bool ZeroInitialization = false);
2925 
2926   static Destroyer destroyCXXObject;
2927 
2928   void EmitCXXDestructorCall(const CXXDestructorDecl *D, CXXDtorType Type,
2929                              bool ForVirtualBase, bool Delegating, Address This,
2930                              QualType ThisTy);
2931 
2932   void EmitNewArrayInitializer(const CXXNewExpr *E, QualType elementType,
2933                                llvm::Type *ElementTy, Address NewPtr,
2934                                llvm::Value *NumElements,
2935                                llvm::Value *AllocSizeWithoutCookie);
2936 
2937   void EmitCXXTemporary(const CXXTemporary *Temporary, QualType TempType,
2938                         Address Ptr);
2939 
2940   void EmitSehCppScopeBegin();
2941   void EmitSehCppScopeEnd();
2942   void EmitSehTryScopeBegin();
2943   void EmitSehTryScopeEnd();
2944 
2945   llvm::Value *EmitLifetimeStart(llvm::TypeSize Size, llvm::Value *Addr);
2946   void EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr);
2947 
2948   llvm::Value *EmitCXXNewExpr(const CXXNewExpr *E);
2949   void EmitCXXDeleteExpr(const CXXDeleteExpr *E);
2950 
2951   void EmitDeleteCall(const FunctionDecl *DeleteFD, llvm::Value *Ptr,
2952                       QualType DeleteTy, llvm::Value *NumElements = nullptr,
2953                       CharUnits CookieSize = CharUnits());
2954 
2955   RValue EmitBuiltinNewDeleteCall(const FunctionProtoType *Type,
2956                                   const CallExpr *TheCallExpr, bool IsDelete);
2957 
2958   llvm::Value *EmitCXXTypeidExpr(const CXXTypeidExpr *E);
2959   llvm::Value *EmitDynamicCast(Address V, const CXXDynamicCastExpr *DCE);
2960   Address EmitCXXUuidofExpr(const CXXUuidofExpr *E);
2961 
2962   /// Situations in which we might emit a check for the suitability of a
2963   /// pointer or glvalue. Needs to be kept in sync with ubsan_handlers.cpp in
2964   /// compiler-rt.
2965   enum TypeCheckKind {
2966     /// Checking the operand of a load. Must be suitably sized and aligned.
2967     TCK_Load,
2968     /// Checking the destination of a store. Must be suitably sized and aligned.
2969     TCK_Store,
2970     /// Checking the bound value in a reference binding. Must be suitably sized
2971     /// and aligned, but is not required to refer to an object (until the
2972     /// reference is used), per core issue 453.
2973     TCK_ReferenceBinding,
2974     /// Checking the object expression in a non-static data member access. Must
2975     /// be an object within its lifetime.
2976     TCK_MemberAccess,
2977     /// Checking the 'this' pointer for a call to a non-static member function.
2978     /// Must be an object within its lifetime.
2979     TCK_MemberCall,
2980     /// Checking the 'this' pointer for a constructor call.
2981     TCK_ConstructorCall,
2982     /// Checking the operand of a static_cast to a derived pointer type. Must be
2983     /// null or an object within its lifetime.
2984     TCK_DowncastPointer,
2985     /// Checking the operand of a static_cast to a derived reference type. Must
2986     /// be an object within its lifetime.
2987     TCK_DowncastReference,
2988     /// Checking the operand of a cast to a base object. Must be suitably sized
2989     /// and aligned.
2990     TCK_Upcast,
2991     /// Checking the operand of a cast to a virtual base object. Must be an
2992     /// object within its lifetime.
2993     TCK_UpcastToVirtualBase,
2994     /// Checking the value assigned to a _Nonnull pointer. Must not be null.
2995     TCK_NonnullAssign,
2996     /// Checking the operand of a dynamic_cast or a typeid expression.  Must be
2997     /// null or an object within its lifetime.
2998     TCK_DynamicOperation
2999   };
3000 
3001   /// Determine whether the pointer type check \p TCK permits null pointers.
3002   static bool isNullPointerAllowed(TypeCheckKind TCK);
3003 
3004   /// Determine whether the pointer type check \p TCK requires a vptr check.
3005   static bool isVptrCheckRequired(TypeCheckKind TCK, QualType Ty);
3006 
3007   /// Whether any type-checking sanitizers are enabled. If \c false,
3008   /// calls to EmitTypeCheck can be skipped.
3009   bool sanitizePerformTypeCheck() const;
3010 
3011   /// Emit a check that \p V is the address of storage of the
3012   /// appropriate size and alignment for an object of type \p Type
3013   /// (or if ArraySize is provided, for an array of that bound).
3014   void EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, llvm::Value *V,
3015                      QualType Type, CharUnits Alignment = CharUnits::Zero(),
3016                      SanitizerSet SkippedChecks = SanitizerSet(),
3017                      llvm::Value *ArraySize = nullptr);
3018 
3019   /// Emit a check that \p Base points into an array object, which
3020   /// we can access at index \p Index. \p Accessed should be \c false if we
3021   /// this expression is used as an lvalue, for instance in "&Arr[Idx]".
3022   void EmitBoundsCheck(const Expr *E, const Expr *Base, llvm::Value *Index,
3023                        QualType IndexType, bool Accessed);
3024 
3025   llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
3026                                        bool isInc, bool isPre);
3027   ComplexPairTy EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
3028                                          bool isInc, bool isPre);
3029 
3030   /// Converts Location to a DebugLoc, if debug information is enabled.
3031   llvm::DebugLoc SourceLocToDebugLoc(SourceLocation Location);
3032 
3033   /// Get the record field index as represented in debug info.
3034   unsigned getDebugInfoFIndex(const RecordDecl *Rec, unsigned FieldIndex);
3035 
3036 
3037   //===--------------------------------------------------------------------===//
3038   //                            Declaration Emission
3039   //===--------------------------------------------------------------------===//
3040 
3041   /// EmitDecl - Emit a declaration.
3042   ///
3043   /// This function can be called with a null (unreachable) insert point.
3044   void EmitDecl(const Decl &D);
3045 
3046   /// EmitVarDecl - Emit a local variable declaration.
3047   ///
3048   /// This function can be called with a null (unreachable) insert point.
3049   void EmitVarDecl(const VarDecl &D);
3050 
3051   void EmitScalarInit(const Expr *init, const ValueDecl *D, LValue lvalue,
3052                       bool capturedByInit);
3053 
3054   typedef void SpecialInitFn(CodeGenFunction &Init, const VarDecl &D,
3055                              llvm::Value *Address);
3056 
3057   /// Determine whether the given initializer is trivial in the sense
3058   /// that it requires no code to be generated.
3059   bool isTrivialInitializer(const Expr *Init);
3060 
3061   /// EmitAutoVarDecl - Emit an auto variable declaration.
3062   ///
3063   /// This function can be called with a null (unreachable) insert point.
3064   void EmitAutoVarDecl(const VarDecl &D);
3065 
3066   class AutoVarEmission {
3067     friend class CodeGenFunction;
3068 
3069     const VarDecl *Variable;
3070 
3071     /// The address of the alloca for languages with explicit address space
3072     /// (e.g. OpenCL) or alloca casted to generic pointer for address space
3073     /// agnostic languages (e.g. C++). Invalid if the variable was emitted
3074     /// as a global constant.
3075     Address Addr;
3076 
3077     llvm::Value *NRVOFlag;
3078 
3079     /// True if the variable is a __block variable that is captured by an
3080     /// escaping block.
3081     bool IsEscapingByRef;
3082 
3083     /// True if the variable is of aggregate type and has a constant
3084     /// initializer.
3085     bool IsConstantAggregate;
3086 
3087     /// Non-null if we should use lifetime annotations.
3088     llvm::Value *SizeForLifetimeMarkers;
3089 
3090     /// Address with original alloca instruction. Invalid if the variable was
3091     /// emitted as a global constant.
3092     Address AllocaAddr;
3093 
3094     struct Invalid {};
3095     AutoVarEmission(Invalid)
3096         : Variable(nullptr), Addr(Address::invalid()),
3097           AllocaAddr(Address::invalid()) {}
3098 
3099     AutoVarEmission(const VarDecl &variable)
3100         : Variable(&variable), Addr(Address::invalid()), NRVOFlag(nullptr),
3101           IsEscapingByRef(false), IsConstantAggregate(false),
3102           SizeForLifetimeMarkers(nullptr), AllocaAddr(Address::invalid()) {}
3103 
3104     bool wasEmittedAsGlobal() const { return !Addr.isValid(); }
3105 
3106   public:
3107     static AutoVarEmission invalid() { return AutoVarEmission(Invalid()); }
3108 
3109     bool useLifetimeMarkers() const {
3110       return SizeForLifetimeMarkers != nullptr;
3111     }
3112     llvm::Value *getSizeForLifetimeMarkers() const {
3113       assert(useLifetimeMarkers());
3114       return SizeForLifetimeMarkers;
3115     }
3116 
3117     /// Returns the raw, allocated address, which is not necessarily
3118     /// the address of the object itself. It is casted to default
3119     /// address space for address space agnostic languages.
3120     Address getAllocatedAddress() const {
3121       return Addr;
3122     }
3123 
3124     /// Returns the address for the original alloca instruction.
3125     Address getOriginalAllocatedAddress() const { return AllocaAddr; }
3126 
3127     /// Returns the address of the object within this declaration.
3128     /// Note that this does not chase the forwarding pointer for
3129     /// __block decls.
3130     Address getObjectAddress(CodeGenFunction &CGF) const {
3131       if (!IsEscapingByRef) return Addr;
3132 
3133       return CGF.emitBlockByrefAddress(Addr, Variable, /*forward*/ false);
3134     }
3135   };
3136   AutoVarEmission EmitAutoVarAlloca(const VarDecl &var);
3137   void EmitAutoVarInit(const AutoVarEmission &emission);
3138   void EmitAutoVarCleanups(const AutoVarEmission &emission);
3139   void emitAutoVarTypeCleanup(const AutoVarEmission &emission,
3140                               QualType::DestructionKind dtorKind);
3141 
3142   /// Emits the alloca and debug information for the size expressions for each
3143   /// dimension of an array. It registers the association of its (1-dimensional)
3144   /// QualTypes and size expression's debug node, so that CGDebugInfo can
3145   /// reference this node when creating the DISubrange object to describe the
3146   /// array types.
3147   void EmitAndRegisterVariableArrayDimensions(CGDebugInfo *DI,
3148                                               const VarDecl &D,
3149                                               bool EmitDebugInfo);
3150 
3151   void EmitStaticVarDecl(const VarDecl &D,
3152                          llvm::GlobalValue::LinkageTypes Linkage);
3153 
3154   class ParamValue {
3155     llvm::Value *Value;
3156     llvm::Type *ElementType;
3157     unsigned Alignment;
3158     ParamValue(llvm::Value *V, llvm::Type *T, unsigned A)
3159         : Value(V), ElementType(T), Alignment(A) {}
3160   public:
3161     static ParamValue forDirect(llvm::Value *value) {
3162       return ParamValue(value, nullptr, 0);
3163     }
3164     static ParamValue forIndirect(Address addr) {
3165       assert(!addr.getAlignment().isZero());
3166       return ParamValue(addr.getPointer(), addr.getElementType(),
3167                         addr.getAlignment().getQuantity());
3168     }
3169 
3170     bool isIndirect() const { return Alignment != 0; }
3171     llvm::Value *getAnyValue() const { return Value; }
3172 
3173     llvm::Value *getDirectValue() const {
3174       assert(!isIndirect());
3175       return Value;
3176     }
3177 
3178     Address getIndirectAddress() const {
3179       assert(isIndirect());
3180       return Address(Value, ElementType, CharUnits::fromQuantity(Alignment),
3181                      KnownNonNull);
3182     }
3183   };
3184 
3185   /// EmitParmDecl - Emit a ParmVarDecl or an ImplicitParamDecl.
3186   void EmitParmDecl(const VarDecl &D, ParamValue Arg, unsigned ArgNo);
3187 
3188   /// protectFromPeepholes - Protect a value that we're intending to
3189   /// store to the side, but which will probably be used later, from
3190   /// aggressive peepholing optimizations that might delete it.
3191   ///
3192   /// Pass the result to unprotectFromPeepholes to declare that
3193   /// protection is no longer required.
3194   ///
3195   /// There's no particular reason why this shouldn't apply to
3196   /// l-values, it's just that no existing peepholes work on pointers.
3197   PeepholeProtection protectFromPeepholes(RValue rvalue);
3198   void unprotectFromPeepholes(PeepholeProtection protection);
3199 
3200   void emitAlignmentAssumptionCheck(llvm::Value *Ptr, QualType Ty,
3201                                     SourceLocation Loc,
3202                                     SourceLocation AssumptionLoc,
3203                                     llvm::Value *Alignment,
3204                                     llvm::Value *OffsetValue,
3205                                     llvm::Value *TheCheck,
3206                                     llvm::Instruction *Assumption);
3207 
3208   void emitAlignmentAssumption(llvm::Value *PtrValue, QualType Ty,
3209                                SourceLocation Loc, SourceLocation AssumptionLoc,
3210                                llvm::Value *Alignment,
3211                                llvm::Value *OffsetValue = nullptr);
3212 
3213   void emitAlignmentAssumption(llvm::Value *PtrValue, const Expr *E,
3214                                SourceLocation AssumptionLoc,
3215                                llvm::Value *Alignment,
3216                                llvm::Value *OffsetValue = nullptr);
3217 
3218   //===--------------------------------------------------------------------===//
3219   //                             Statement Emission
3220   //===--------------------------------------------------------------------===//
3221 
3222   /// EmitStopPoint - Emit a debug stoppoint if we are emitting debug info.
3223   void EmitStopPoint(const Stmt *S);
3224 
3225   /// EmitStmt - Emit the code for the statement \arg S. It is legal to call
3226   /// this function even if there is no current insertion point.
3227   ///
3228   /// This function may clear the current insertion point; callers should use
3229   /// EnsureInsertPoint if they wish to subsequently generate code without first
3230   /// calling EmitBlock, EmitBranch, or EmitStmt.
3231   void EmitStmt(const Stmt *S, ArrayRef<const Attr *> Attrs = std::nullopt);
3232 
3233   /// EmitSimpleStmt - Try to emit a "simple" statement which does not
3234   /// necessarily require an insertion point or debug information; typically
3235   /// because the statement amounts to a jump or a container of other
3236   /// statements.
3237   ///
3238   /// \return True if the statement was handled.
3239   bool EmitSimpleStmt(const Stmt *S, ArrayRef<const Attr *> Attrs);
3240 
3241   Address EmitCompoundStmt(const CompoundStmt &S, bool GetLast = false,
3242                            AggValueSlot AVS = AggValueSlot::ignored());
3243   Address EmitCompoundStmtWithoutScope(const CompoundStmt &S,
3244                                        bool GetLast = false,
3245                                        AggValueSlot AVS =
3246                                                 AggValueSlot::ignored());
3247 
3248   /// EmitLabel - Emit the block for the given label. It is legal to call this
3249   /// function even if there is no current insertion point.
3250   void EmitLabel(const LabelDecl *D); // helper for EmitLabelStmt.
3251 
3252   void EmitLabelStmt(const LabelStmt &S);
3253   void EmitAttributedStmt(const AttributedStmt &S);
3254   void EmitGotoStmt(const GotoStmt &S);
3255   void EmitIndirectGotoStmt(const IndirectGotoStmt &S);
3256   void EmitIfStmt(const IfStmt &S);
3257 
3258   void EmitWhileStmt(const WhileStmt &S,
3259                      ArrayRef<const Attr *> Attrs = std::nullopt);
3260   void EmitDoStmt(const DoStmt &S, ArrayRef<const Attr *> Attrs = std::nullopt);
3261   void EmitForStmt(const ForStmt &S,
3262                    ArrayRef<const Attr *> Attrs = std::nullopt);
3263   void EmitReturnStmt(const ReturnStmt &S);
3264   void EmitDeclStmt(const DeclStmt &S);
3265   void EmitBreakStmt(const BreakStmt &S);
3266   void EmitContinueStmt(const ContinueStmt &S);
3267   void EmitSwitchStmt(const SwitchStmt &S);
3268   void EmitDefaultStmt(const DefaultStmt &S, ArrayRef<const Attr *> Attrs);
3269   void EmitCaseStmt(const CaseStmt &S, ArrayRef<const Attr *> Attrs);
3270   void EmitCaseStmtRange(const CaseStmt &S, ArrayRef<const Attr *> Attrs);
3271   void EmitAsmStmt(const AsmStmt &S);
3272 
3273   void EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S);
3274   void EmitObjCAtTryStmt(const ObjCAtTryStmt &S);
3275   void EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S);
3276   void EmitObjCAtSynchronizedStmt(const ObjCAtSynchronizedStmt &S);
3277   void EmitObjCAutoreleasePoolStmt(const ObjCAutoreleasePoolStmt &S);
3278 
3279   void EmitCoroutineBody(const CoroutineBodyStmt &S);
3280   void EmitCoreturnStmt(const CoreturnStmt &S);
3281   RValue EmitCoawaitExpr(const CoawaitExpr &E,
3282                          AggValueSlot aggSlot = AggValueSlot::ignored(),
3283                          bool ignoreResult = false);
3284   LValue EmitCoawaitLValue(const CoawaitExpr *E);
3285   RValue EmitCoyieldExpr(const CoyieldExpr &E,
3286                          AggValueSlot aggSlot = AggValueSlot::ignored(),
3287                          bool ignoreResult = false);
3288   LValue EmitCoyieldLValue(const CoyieldExpr *E);
3289   RValue EmitCoroutineIntrinsic(const CallExpr *E, unsigned int IID);
3290 
3291   void EnterCXXTryStmt(const CXXTryStmt &S, bool IsFnTryBlock = false);
3292   void ExitCXXTryStmt(const CXXTryStmt &S, bool IsFnTryBlock = false);
3293 
3294   void EmitCXXTryStmt(const CXXTryStmt &S);
3295   void EmitSEHTryStmt(const SEHTryStmt &S);
3296   void EmitSEHLeaveStmt(const SEHLeaveStmt &S);
3297   void EnterSEHTryStmt(const SEHTryStmt &S);
3298   void ExitSEHTryStmt(const SEHTryStmt &S);
3299   void VolatilizeTryBlocks(llvm::BasicBlock *BB,
3300                            llvm::SmallPtrSet<llvm::BasicBlock *, 10> &V);
3301 
3302   void pushSEHCleanup(CleanupKind kind,
3303                       llvm::Function *FinallyFunc);
3304   void startOutlinedSEHHelper(CodeGenFunction &ParentCGF, bool IsFilter,
3305                               const Stmt *OutlinedStmt);
3306 
3307   llvm::Function *GenerateSEHFilterFunction(CodeGenFunction &ParentCGF,
3308                                             const SEHExceptStmt &Except);
3309 
3310   llvm::Function *GenerateSEHFinallyFunction(CodeGenFunction &ParentCGF,
3311                                              const SEHFinallyStmt &Finally);
3312 
3313   void EmitSEHExceptionCodeSave(CodeGenFunction &ParentCGF,
3314                                 llvm::Value *ParentFP,
3315                                 llvm::Value *EntryEBP);
3316   llvm::Value *EmitSEHExceptionCode();
3317   llvm::Value *EmitSEHExceptionInfo();
3318   llvm::Value *EmitSEHAbnormalTermination();
3319 
3320   /// Emit simple code for OpenMP directives in Simd-only mode.
3321   void EmitSimpleOMPExecutableDirective(const OMPExecutableDirective &D);
3322 
3323   /// Scan the outlined statement for captures from the parent function. For
3324   /// each capture, mark the capture as escaped and emit a call to
3325   /// llvm.localrecover. Insert the localrecover result into the LocalDeclMap.
3326   void EmitCapturedLocals(CodeGenFunction &ParentCGF, const Stmt *OutlinedStmt,
3327                           bool IsFilter);
3328 
3329   /// Recovers the address of a local in a parent function. ParentVar is the
3330   /// address of the variable used in the immediate parent function. It can
3331   /// either be an alloca or a call to llvm.localrecover if there are nested
3332   /// outlined functions. ParentFP is the frame pointer of the outermost parent
3333   /// frame.
3334   Address recoverAddrOfEscapedLocal(CodeGenFunction &ParentCGF,
3335                                     Address ParentVar,
3336                                     llvm::Value *ParentFP);
3337 
3338   void EmitCXXForRangeStmt(const CXXForRangeStmt &S,
3339                            ArrayRef<const Attr *> Attrs = std::nullopt);
3340 
3341   /// Controls insertion of cancellation exit blocks in worksharing constructs.
3342   class OMPCancelStackRAII {
3343     CodeGenFunction &CGF;
3344 
3345   public:
3346     OMPCancelStackRAII(CodeGenFunction &CGF, OpenMPDirectiveKind Kind,
3347                        bool HasCancel)
3348         : CGF(CGF) {
3349       CGF.OMPCancelStack.enter(CGF, Kind, HasCancel);
3350     }
3351     ~OMPCancelStackRAII() { CGF.OMPCancelStack.exit(CGF); }
3352   };
3353 
3354   /// Returns calculated size of the specified type.
3355   llvm::Value *getTypeSize(QualType Ty);
3356   LValue InitCapturedStruct(const CapturedStmt &S);
3357   llvm::Function *EmitCapturedStmt(const CapturedStmt &S, CapturedRegionKind K);
3358   llvm::Function *GenerateCapturedStmtFunction(const CapturedStmt &S);
3359   Address GenerateCapturedStmtArgument(const CapturedStmt &S);
3360   llvm::Function *GenerateOpenMPCapturedStmtFunction(const CapturedStmt &S,
3361                                                      SourceLocation Loc);
3362   void GenerateOpenMPCapturedVars(const CapturedStmt &S,
3363                                   SmallVectorImpl<llvm::Value *> &CapturedVars);
3364   void emitOMPSimpleStore(LValue LVal, RValue RVal, QualType RValTy,
3365                           SourceLocation Loc);
3366   /// Perform element by element copying of arrays with type \a
3367   /// OriginalType from \a SrcAddr to \a DestAddr using copying procedure
3368   /// generated by \a CopyGen.
3369   ///
3370   /// \param DestAddr Address of the destination array.
3371   /// \param SrcAddr Address of the source array.
3372   /// \param OriginalType Type of destination and source arrays.
3373   /// \param CopyGen Copying procedure that copies value of single array element
3374   /// to another single array element.
3375   void EmitOMPAggregateAssign(
3376       Address DestAddr, Address SrcAddr, QualType OriginalType,
3377       const llvm::function_ref<void(Address, Address)> CopyGen);
3378   /// Emit proper copying of data from one variable to another.
3379   ///
3380   /// \param OriginalType Original type of the copied variables.
3381   /// \param DestAddr Destination address.
3382   /// \param SrcAddr Source address.
3383   /// \param DestVD Destination variable used in \a CopyExpr (for arrays, has
3384   /// type of the base array element).
3385   /// \param SrcVD Source variable used in \a CopyExpr (for arrays, has type of
3386   /// the base array element).
3387   /// \param Copy Actual copygin expression for copying data from \a SrcVD to \a
3388   /// DestVD.
3389   void EmitOMPCopy(QualType OriginalType,
3390                    Address DestAddr, Address SrcAddr,
3391                    const VarDecl *DestVD, const VarDecl *SrcVD,
3392                    const Expr *Copy);
3393   /// Emit atomic update code for constructs: \a X = \a X \a BO \a E or
3394   /// \a X = \a E \a BO \a E.
3395   ///
3396   /// \param X Value to be updated.
3397   /// \param E Update value.
3398   /// \param BO Binary operation for update operation.
3399   /// \param IsXLHSInRHSPart true if \a X is LHS in RHS part of the update
3400   /// expression, false otherwise.
3401   /// \param AO Atomic ordering of the generated atomic instructions.
3402   /// \param CommonGen Code generator for complex expressions that cannot be
3403   /// expressed through atomicrmw instruction.
3404   /// \returns <true, OldAtomicValue> if simple 'atomicrmw' instruction was
3405   /// generated, <false, RValue::get(nullptr)> otherwise.
3406   std::pair<bool, RValue> EmitOMPAtomicSimpleUpdateExpr(
3407       LValue X, RValue E, BinaryOperatorKind BO, bool IsXLHSInRHSPart,
3408       llvm::AtomicOrdering AO, SourceLocation Loc,
3409       const llvm::function_ref<RValue(RValue)> CommonGen);
3410   bool EmitOMPFirstprivateClause(const OMPExecutableDirective &D,
3411                                  OMPPrivateScope &PrivateScope);
3412   void EmitOMPPrivateClause(const OMPExecutableDirective &D,
3413                             OMPPrivateScope &PrivateScope);
3414   void EmitOMPUseDevicePtrClause(
3415       const OMPUseDevicePtrClause &C, OMPPrivateScope &PrivateScope,
3416       const llvm::DenseMap<const ValueDecl *, llvm::Value *>
3417           CaptureDeviceAddrMap);
3418   void EmitOMPUseDeviceAddrClause(
3419       const OMPUseDeviceAddrClause &C, OMPPrivateScope &PrivateScope,
3420       const llvm::DenseMap<const ValueDecl *, llvm::Value *>
3421           CaptureDeviceAddrMap);
3422   /// Emit code for copyin clause in \a D directive. The next code is
3423   /// generated at the start of outlined functions for directives:
3424   /// \code
3425   /// threadprivate_var1 = master_threadprivate_var1;
3426   /// operator=(threadprivate_var2, master_threadprivate_var2);
3427   /// ...
3428   /// __kmpc_barrier(&loc, global_tid);
3429   /// \endcode
3430   ///
3431   /// \param D OpenMP directive possibly with 'copyin' clause(s).
3432   /// \returns true if at least one copyin variable is found, false otherwise.
3433   bool EmitOMPCopyinClause(const OMPExecutableDirective &D);
3434   /// Emit initial code for lastprivate variables. If some variable is
3435   /// not also firstprivate, then the default initialization is used. Otherwise
3436   /// initialization of this variable is performed by EmitOMPFirstprivateClause
3437   /// method.
3438   ///
3439   /// \param D Directive that may have 'lastprivate' directives.
3440   /// \param PrivateScope Private scope for capturing lastprivate variables for
3441   /// proper codegen in internal captured statement.
3442   ///
3443   /// \returns true if there is at least one lastprivate variable, false
3444   /// otherwise.
3445   bool EmitOMPLastprivateClauseInit(const OMPExecutableDirective &D,
3446                                     OMPPrivateScope &PrivateScope);
3447   /// Emit final copying of lastprivate values to original variables at
3448   /// the end of the worksharing or simd directive.
3449   ///
3450   /// \param D Directive that has at least one 'lastprivate' directives.
3451   /// \param IsLastIterCond Boolean condition that must be set to 'i1 true' if
3452   /// it is the last iteration of the loop code in associated directive, or to
3453   /// 'i1 false' otherwise. If this item is nullptr, no final check is required.
3454   void EmitOMPLastprivateClauseFinal(const OMPExecutableDirective &D,
3455                                      bool NoFinals,
3456                                      llvm::Value *IsLastIterCond = nullptr);
3457   /// Emit initial code for linear clauses.
3458   void EmitOMPLinearClause(const OMPLoopDirective &D,
3459                            CodeGenFunction::OMPPrivateScope &PrivateScope);
3460   /// Emit final code for linear clauses.
3461   /// \param CondGen Optional conditional code for final part of codegen for
3462   /// linear clause.
3463   void EmitOMPLinearClauseFinal(
3464       const OMPLoopDirective &D,
3465       const llvm::function_ref<llvm::Value *(CodeGenFunction &)> CondGen);
3466   /// Emit initial code for reduction variables. Creates reduction copies
3467   /// and initializes them with the values according to OpenMP standard.
3468   ///
3469   /// \param D Directive (possibly) with the 'reduction' clause.
3470   /// \param PrivateScope Private scope for capturing reduction variables for
3471   /// proper codegen in internal captured statement.
3472   ///
3473   void EmitOMPReductionClauseInit(const OMPExecutableDirective &D,
3474                                   OMPPrivateScope &PrivateScope,
3475                                   bool ForInscan = false);
3476   /// Emit final update of reduction values to original variables at
3477   /// the end of the directive.
3478   ///
3479   /// \param D Directive that has at least one 'reduction' directives.
3480   /// \param ReductionKind The kind of reduction to perform.
3481   void EmitOMPReductionClauseFinal(const OMPExecutableDirective &D,
3482                                    const OpenMPDirectiveKind ReductionKind);
3483   /// Emit initial code for linear variables. Creates private copies
3484   /// and initializes them with the values according to OpenMP standard.
3485   ///
3486   /// \param D Directive (possibly) with the 'linear' clause.
3487   /// \return true if at least one linear variable is found that should be
3488   /// initialized with the value of the original variable, false otherwise.
3489   bool EmitOMPLinearClauseInit(const OMPLoopDirective &D);
3490 
3491   typedef const llvm::function_ref<void(CodeGenFunction & /*CGF*/,
3492                                         llvm::Function * /*OutlinedFn*/,
3493                                         const OMPTaskDataTy & /*Data*/)>
3494       TaskGenTy;
3495   void EmitOMPTaskBasedDirective(const OMPExecutableDirective &S,
3496                                  const OpenMPDirectiveKind CapturedRegion,
3497                                  const RegionCodeGenTy &BodyGen,
3498                                  const TaskGenTy &TaskGen, OMPTaskDataTy &Data);
3499   struct OMPTargetDataInfo {
3500     Address BasePointersArray = Address::invalid();
3501     Address PointersArray = Address::invalid();
3502     Address SizesArray = Address::invalid();
3503     Address MappersArray = Address::invalid();
3504     unsigned NumberOfTargetItems = 0;
3505     explicit OMPTargetDataInfo() = default;
3506     OMPTargetDataInfo(Address BasePointersArray, Address PointersArray,
3507                       Address SizesArray, Address MappersArray,
3508                       unsigned NumberOfTargetItems)
3509         : BasePointersArray(BasePointersArray), PointersArray(PointersArray),
3510           SizesArray(SizesArray), MappersArray(MappersArray),
3511           NumberOfTargetItems(NumberOfTargetItems) {}
3512   };
3513   void EmitOMPTargetTaskBasedDirective(const OMPExecutableDirective &S,
3514                                        const RegionCodeGenTy &BodyGen,
3515                                        OMPTargetDataInfo &InputInfo);
3516   void processInReduction(const OMPExecutableDirective &S,
3517                           OMPTaskDataTy &Data,
3518                           CodeGenFunction &CGF,
3519                           const CapturedStmt *CS,
3520                           OMPPrivateScope &Scope);
3521   void EmitOMPMetaDirective(const OMPMetaDirective &S);
3522   void EmitOMPParallelDirective(const OMPParallelDirective &S);
3523   void EmitOMPSimdDirective(const OMPSimdDirective &S);
3524   void EmitOMPTileDirective(const OMPTileDirective &S);
3525   void EmitOMPUnrollDirective(const OMPUnrollDirective &S);
3526   void EmitOMPForDirective(const OMPForDirective &S);
3527   void EmitOMPForSimdDirective(const OMPForSimdDirective &S);
3528   void EmitOMPSectionsDirective(const OMPSectionsDirective &S);
3529   void EmitOMPSectionDirective(const OMPSectionDirective &S);
3530   void EmitOMPSingleDirective(const OMPSingleDirective &S);
3531   void EmitOMPMasterDirective(const OMPMasterDirective &S);
3532   void EmitOMPMaskedDirective(const OMPMaskedDirective &S);
3533   void EmitOMPCriticalDirective(const OMPCriticalDirective &S);
3534   void EmitOMPParallelForDirective(const OMPParallelForDirective &S);
3535   void EmitOMPParallelForSimdDirective(const OMPParallelForSimdDirective &S);
3536   void EmitOMPParallelSectionsDirective(const OMPParallelSectionsDirective &S);
3537   void EmitOMPParallelMasterDirective(const OMPParallelMasterDirective &S);
3538   void EmitOMPTaskDirective(const OMPTaskDirective &S);
3539   void EmitOMPTaskyieldDirective(const OMPTaskyieldDirective &S);
3540   void EmitOMPErrorDirective(const OMPErrorDirective &S);
3541   void EmitOMPBarrierDirective(const OMPBarrierDirective &S);
3542   void EmitOMPTaskwaitDirective(const OMPTaskwaitDirective &S);
3543   void EmitOMPTaskgroupDirective(const OMPTaskgroupDirective &S);
3544   void EmitOMPFlushDirective(const OMPFlushDirective &S);
3545   void EmitOMPDepobjDirective(const OMPDepobjDirective &S);
3546   void EmitOMPScanDirective(const OMPScanDirective &S);
3547   void EmitOMPOrderedDirective(const OMPOrderedDirective &S);
3548   void EmitOMPAtomicDirective(const OMPAtomicDirective &S);
3549   void EmitOMPTargetDirective(const OMPTargetDirective &S);
3550   void EmitOMPTargetDataDirective(const OMPTargetDataDirective &S);
3551   void EmitOMPTargetEnterDataDirective(const OMPTargetEnterDataDirective &S);
3552   void EmitOMPTargetExitDataDirective(const OMPTargetExitDataDirective &S);
3553   void EmitOMPTargetUpdateDirective(const OMPTargetUpdateDirective &S);
3554   void EmitOMPTargetParallelDirective(const OMPTargetParallelDirective &S);
3555   void
3556   EmitOMPTargetParallelForDirective(const OMPTargetParallelForDirective &S);
3557   void EmitOMPTeamsDirective(const OMPTeamsDirective &S);
3558   void
3559   EmitOMPCancellationPointDirective(const OMPCancellationPointDirective &S);
3560   void EmitOMPCancelDirective(const OMPCancelDirective &S);
3561   void EmitOMPTaskLoopBasedDirective(const OMPLoopDirective &S);
3562   void EmitOMPTaskLoopDirective(const OMPTaskLoopDirective &S);
3563   void EmitOMPTaskLoopSimdDirective(const OMPTaskLoopSimdDirective &S);
3564   void EmitOMPMasterTaskLoopDirective(const OMPMasterTaskLoopDirective &S);
3565   void
3566   EmitOMPMasterTaskLoopSimdDirective(const OMPMasterTaskLoopSimdDirective &S);
3567   void EmitOMPParallelMasterTaskLoopDirective(
3568       const OMPParallelMasterTaskLoopDirective &S);
3569   void EmitOMPParallelMasterTaskLoopSimdDirective(
3570       const OMPParallelMasterTaskLoopSimdDirective &S);
3571   void EmitOMPDistributeDirective(const OMPDistributeDirective &S);
3572   void EmitOMPDistributeParallelForDirective(
3573       const OMPDistributeParallelForDirective &S);
3574   void EmitOMPDistributeParallelForSimdDirective(
3575       const OMPDistributeParallelForSimdDirective &S);
3576   void EmitOMPDistributeSimdDirective(const OMPDistributeSimdDirective &S);
3577   void EmitOMPTargetParallelForSimdDirective(
3578       const OMPTargetParallelForSimdDirective &S);
3579   void EmitOMPTargetSimdDirective(const OMPTargetSimdDirective &S);
3580   void EmitOMPTeamsDistributeDirective(const OMPTeamsDistributeDirective &S);
3581   void
3582   EmitOMPTeamsDistributeSimdDirective(const OMPTeamsDistributeSimdDirective &S);
3583   void EmitOMPTeamsDistributeParallelForSimdDirective(
3584       const OMPTeamsDistributeParallelForSimdDirective &S);
3585   void EmitOMPTeamsDistributeParallelForDirective(
3586       const OMPTeamsDistributeParallelForDirective &S);
3587   void EmitOMPTargetTeamsDirective(const OMPTargetTeamsDirective &S);
3588   void EmitOMPTargetTeamsDistributeDirective(
3589       const OMPTargetTeamsDistributeDirective &S);
3590   void EmitOMPTargetTeamsDistributeParallelForDirective(
3591       const OMPTargetTeamsDistributeParallelForDirective &S);
3592   void EmitOMPTargetTeamsDistributeParallelForSimdDirective(
3593       const OMPTargetTeamsDistributeParallelForSimdDirective &S);
3594   void EmitOMPTargetTeamsDistributeSimdDirective(
3595       const OMPTargetTeamsDistributeSimdDirective &S);
3596   void EmitOMPGenericLoopDirective(const OMPGenericLoopDirective &S);
3597   void EmitOMPParallelGenericLoopDirective(const OMPLoopDirective &S);
3598   void EmitOMPTargetParallelGenericLoopDirective(
3599       const OMPTargetParallelGenericLoopDirective &S);
3600   void EmitOMPTargetTeamsGenericLoopDirective(
3601       const OMPTargetTeamsGenericLoopDirective &S);
3602   void EmitOMPTeamsGenericLoopDirective(const OMPTeamsGenericLoopDirective &S);
3603   void EmitOMPInteropDirective(const OMPInteropDirective &S);
3604   void EmitOMPParallelMaskedDirective(const OMPParallelMaskedDirective &S);
3605 
3606   /// Emit device code for the target directive.
3607   static void EmitOMPTargetDeviceFunction(CodeGenModule &CGM,
3608                                           StringRef ParentName,
3609                                           const OMPTargetDirective &S);
3610   static void
3611   EmitOMPTargetParallelDeviceFunction(CodeGenModule &CGM, StringRef ParentName,
3612                                       const OMPTargetParallelDirective &S);
3613   /// Emit device code for the target parallel for directive.
3614   static void EmitOMPTargetParallelForDeviceFunction(
3615       CodeGenModule &CGM, StringRef ParentName,
3616       const OMPTargetParallelForDirective &S);
3617   /// Emit device code for the target parallel for simd directive.
3618   static void EmitOMPTargetParallelForSimdDeviceFunction(
3619       CodeGenModule &CGM, StringRef ParentName,
3620       const OMPTargetParallelForSimdDirective &S);
3621   /// Emit device code for the target teams directive.
3622   static void
3623   EmitOMPTargetTeamsDeviceFunction(CodeGenModule &CGM, StringRef ParentName,
3624                                    const OMPTargetTeamsDirective &S);
3625   /// Emit device code for the target teams distribute directive.
3626   static void EmitOMPTargetTeamsDistributeDeviceFunction(
3627       CodeGenModule &CGM, StringRef ParentName,
3628       const OMPTargetTeamsDistributeDirective &S);
3629   /// Emit device code for the target teams distribute simd directive.
3630   static void EmitOMPTargetTeamsDistributeSimdDeviceFunction(
3631       CodeGenModule &CGM, StringRef ParentName,
3632       const OMPTargetTeamsDistributeSimdDirective &S);
3633   /// Emit device code for the target simd directive.
3634   static void EmitOMPTargetSimdDeviceFunction(CodeGenModule &CGM,
3635                                               StringRef ParentName,
3636                                               const OMPTargetSimdDirective &S);
3637   /// Emit device code for the target teams distribute parallel for simd
3638   /// directive.
3639   static void EmitOMPTargetTeamsDistributeParallelForSimdDeviceFunction(
3640       CodeGenModule &CGM, StringRef ParentName,
3641       const OMPTargetTeamsDistributeParallelForSimdDirective &S);
3642 
3643   /// Emit device code for the target teams loop directive.
3644   static void EmitOMPTargetTeamsGenericLoopDeviceFunction(
3645       CodeGenModule &CGM, StringRef ParentName,
3646       const OMPTargetTeamsGenericLoopDirective &S);
3647 
3648   /// Emit device code for the target parallel loop directive.
3649   static void EmitOMPTargetParallelGenericLoopDeviceFunction(
3650       CodeGenModule &CGM, StringRef ParentName,
3651       const OMPTargetParallelGenericLoopDirective &S);
3652 
3653   static void EmitOMPTargetTeamsDistributeParallelForDeviceFunction(
3654       CodeGenModule &CGM, StringRef ParentName,
3655       const OMPTargetTeamsDistributeParallelForDirective &S);
3656 
3657   /// Emit the Stmt \p S and return its topmost canonical loop, if any.
3658   /// TODO: The \p Depth paramter is not yet implemented and must be 1. In the
3659   /// future it is meant to be the number of loops expected in the loop nests
3660   /// (usually specified by the "collapse" clause) that are collapsed to a
3661   /// single loop by this function.
3662   llvm::CanonicalLoopInfo *EmitOMPCollapsedCanonicalLoopNest(const Stmt *S,
3663                                                              int Depth);
3664 
3665   /// Emit an OMPCanonicalLoop using the OpenMPIRBuilder.
3666   void EmitOMPCanonicalLoop(const OMPCanonicalLoop *S);
3667 
3668   /// Emit inner loop of the worksharing/simd construct.
3669   ///
3670   /// \param S Directive, for which the inner loop must be emitted.
3671   /// \param RequiresCleanup true, if directive has some associated private
3672   /// variables.
3673   /// \param LoopCond Bollean condition for loop continuation.
3674   /// \param IncExpr Increment expression for loop control variable.
3675   /// \param BodyGen Generator for the inner body of the inner loop.
3676   /// \param PostIncGen Genrator for post-increment code (required for ordered
3677   /// loop directvies).
3678   void EmitOMPInnerLoop(
3679       const OMPExecutableDirective &S, bool RequiresCleanup,
3680       const Expr *LoopCond, const Expr *IncExpr,
3681       const llvm::function_ref<void(CodeGenFunction &)> BodyGen,
3682       const llvm::function_ref<void(CodeGenFunction &)> PostIncGen);
3683 
3684   JumpDest getOMPCancelDestination(OpenMPDirectiveKind Kind);
3685   /// Emit initial code for loop counters of loop-based directives.
3686   void EmitOMPPrivateLoopCounters(const OMPLoopDirective &S,
3687                                   OMPPrivateScope &LoopScope);
3688 
3689   /// Helper for the OpenMP loop directives.
3690   void EmitOMPLoopBody(const OMPLoopDirective &D, JumpDest LoopExit);
3691 
3692   /// Emit code for the worksharing loop-based directive.
3693   /// \return true, if this construct has any lastprivate clause, false -
3694   /// otherwise.
3695   bool EmitOMPWorksharingLoop(const OMPLoopDirective &S, Expr *EUB,
3696                               const CodeGenLoopBoundsTy &CodeGenLoopBounds,
3697                               const CodeGenDispatchBoundsTy &CGDispatchBounds);
3698 
3699   /// Emit code for the distribute loop-based directive.
3700   void EmitOMPDistributeLoop(const OMPLoopDirective &S,
3701                              const CodeGenLoopTy &CodeGenLoop, Expr *IncExpr);
3702 
3703   /// Helpers for the OpenMP loop directives.
3704   void EmitOMPSimdInit(const OMPLoopDirective &D);
3705   void EmitOMPSimdFinal(
3706       const OMPLoopDirective &D,
3707       const llvm::function_ref<llvm::Value *(CodeGenFunction &)> CondGen);
3708 
3709   /// Emits the lvalue for the expression with possibly captured variable.
3710   LValue EmitOMPSharedLValue(const Expr *E);
3711 
3712 private:
3713   /// Helpers for blocks.
3714   llvm::Value *EmitBlockLiteral(const CGBlockInfo &Info);
3715 
3716   /// struct with the values to be passed to the OpenMP loop-related functions
3717   struct OMPLoopArguments {
3718     /// loop lower bound
3719     Address LB = Address::invalid();
3720     /// loop upper bound
3721     Address UB = Address::invalid();
3722     /// loop stride
3723     Address ST = Address::invalid();
3724     /// isLastIteration argument for runtime functions
3725     Address IL = Address::invalid();
3726     /// Chunk value generated by sema
3727     llvm::Value *Chunk = nullptr;
3728     /// EnsureUpperBound
3729     Expr *EUB = nullptr;
3730     /// IncrementExpression
3731     Expr *IncExpr = nullptr;
3732     /// Loop initialization
3733     Expr *Init = nullptr;
3734     /// Loop exit condition
3735     Expr *Cond = nullptr;
3736     /// Update of LB after a whole chunk has been executed
3737     Expr *NextLB = nullptr;
3738     /// Update of UB after a whole chunk has been executed
3739     Expr *NextUB = nullptr;
3740     OMPLoopArguments() = default;
3741     OMPLoopArguments(Address LB, Address UB, Address ST, Address IL,
3742                      llvm::Value *Chunk = nullptr, Expr *EUB = nullptr,
3743                      Expr *IncExpr = nullptr, Expr *Init = nullptr,
3744                      Expr *Cond = nullptr, Expr *NextLB = nullptr,
3745                      Expr *NextUB = nullptr)
3746         : LB(LB), UB(UB), ST(ST), IL(IL), Chunk(Chunk), EUB(EUB),
3747           IncExpr(IncExpr), Init(Init), Cond(Cond), NextLB(NextLB),
3748           NextUB(NextUB) {}
3749   };
3750   void EmitOMPOuterLoop(bool DynamicOrOrdered, bool IsMonotonic,
3751                         const OMPLoopDirective &S, OMPPrivateScope &LoopScope,
3752                         const OMPLoopArguments &LoopArgs,
3753                         const CodeGenLoopTy &CodeGenLoop,
3754                         const CodeGenOrderedTy &CodeGenOrdered);
3755   void EmitOMPForOuterLoop(const OpenMPScheduleTy &ScheduleKind,
3756                            bool IsMonotonic, const OMPLoopDirective &S,
3757                            OMPPrivateScope &LoopScope, bool Ordered,
3758                            const OMPLoopArguments &LoopArgs,
3759                            const CodeGenDispatchBoundsTy &CGDispatchBounds);
3760   void EmitOMPDistributeOuterLoop(OpenMPDistScheduleClauseKind ScheduleKind,
3761                                   const OMPLoopDirective &S,
3762                                   OMPPrivateScope &LoopScope,
3763                                   const OMPLoopArguments &LoopArgs,
3764                                   const CodeGenLoopTy &CodeGenLoopContent);
3765   /// Emit code for sections directive.
3766   void EmitSections(const OMPExecutableDirective &S);
3767 
3768 public:
3769 
3770   //===--------------------------------------------------------------------===//
3771   //                         LValue Expression Emission
3772   //===--------------------------------------------------------------------===//
3773 
3774   /// Create a check that a scalar RValue is non-null.
3775   llvm::Value *EmitNonNullRValueCheck(RValue RV, QualType T);
3776 
3777   /// GetUndefRValue - Get an appropriate 'undef' rvalue for the given type.
3778   RValue GetUndefRValue(QualType Ty);
3779 
3780   /// EmitUnsupportedRValue - Emit a dummy r-value using the type of E
3781   /// and issue an ErrorUnsupported style diagnostic (using the
3782   /// provided Name).
3783   RValue EmitUnsupportedRValue(const Expr *E,
3784                                const char *Name);
3785 
3786   /// EmitUnsupportedLValue - Emit a dummy l-value using the type of E and issue
3787   /// an ErrorUnsupported style diagnostic (using the provided Name).
3788   LValue EmitUnsupportedLValue(const Expr *E,
3789                                const char *Name);
3790 
3791   /// EmitLValue - Emit code to compute a designator that specifies the location
3792   /// of the expression.
3793   ///
3794   /// This can return one of two things: a simple address or a bitfield
3795   /// reference.  In either case, the LLVM Value* in the LValue structure is
3796   /// guaranteed to be an LLVM pointer type.
3797   ///
3798   /// If this returns a bitfield reference, nothing about the pointee type of
3799   /// the LLVM value is known: For example, it may not be a pointer to an
3800   /// integer.
3801   ///
3802   /// If this returns a normal address, and if the lvalue's C type is fixed
3803   /// size, this method guarantees that the returned pointer type will point to
3804   /// an LLVM type of the same size of the lvalue's type.  If the lvalue has a
3805   /// variable length type, this is not possible.
3806   ///
3807   LValue EmitLValue(const Expr *E,
3808                     KnownNonNull_t IsKnownNonNull = NotKnownNonNull);
3809 
3810 private:
3811   LValue EmitLValueHelper(const Expr *E, KnownNonNull_t IsKnownNonNull);
3812 
3813 public:
3814   /// Same as EmitLValue but additionally we generate checking code to
3815   /// guard against undefined behavior.  This is only suitable when we know
3816   /// that the address will be used to access the object.
3817   LValue EmitCheckedLValue(const Expr *E, TypeCheckKind TCK);
3818 
3819   RValue convertTempToRValue(Address addr, QualType type,
3820                              SourceLocation Loc);
3821 
3822   void EmitAtomicInit(Expr *E, LValue lvalue);
3823 
3824   bool LValueIsSuitableForInlineAtomic(LValue Src);
3825 
3826   RValue EmitAtomicLoad(LValue LV, SourceLocation SL,
3827                         AggValueSlot Slot = AggValueSlot::ignored());
3828 
3829   RValue EmitAtomicLoad(LValue lvalue, SourceLocation loc,
3830                         llvm::AtomicOrdering AO, bool IsVolatile = false,
3831                         AggValueSlot slot = AggValueSlot::ignored());
3832 
3833   void EmitAtomicStore(RValue rvalue, LValue lvalue, bool isInit);
3834 
3835   void EmitAtomicStore(RValue rvalue, LValue lvalue, llvm::AtomicOrdering AO,
3836                        bool IsVolatile, bool isInit);
3837 
3838   std::pair<RValue, llvm::Value *> EmitAtomicCompareExchange(
3839       LValue Obj, RValue Expected, RValue Desired, SourceLocation Loc,
3840       llvm::AtomicOrdering Success =
3841           llvm::AtomicOrdering::SequentiallyConsistent,
3842       llvm::AtomicOrdering Failure =
3843           llvm::AtomicOrdering::SequentiallyConsistent,
3844       bool IsWeak = false, AggValueSlot Slot = AggValueSlot::ignored());
3845 
3846   void EmitAtomicUpdate(LValue LVal, llvm::AtomicOrdering AO,
3847                         const llvm::function_ref<RValue(RValue)> &UpdateOp,
3848                         bool IsVolatile);
3849 
3850   /// EmitToMemory - Change a scalar value from its value
3851   /// representation to its in-memory representation.
3852   llvm::Value *EmitToMemory(llvm::Value *Value, QualType Ty);
3853 
3854   /// EmitFromMemory - Change a scalar value from its memory
3855   /// representation to its value representation.
3856   llvm::Value *EmitFromMemory(llvm::Value *Value, QualType Ty);
3857 
3858   /// Check if the scalar \p Value is within the valid range for the given
3859   /// type \p Ty.
3860   ///
3861   /// Returns true if a check is needed (even if the range is unknown).
3862   bool EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
3863                             SourceLocation Loc);
3864 
3865   /// EmitLoadOfScalar - Load a scalar value from an address, taking
3866   /// care to appropriately convert from the memory representation to
3867   /// the LLVM value representation.
3868   llvm::Value *EmitLoadOfScalar(Address Addr, bool Volatile, QualType Ty,
3869                                 SourceLocation Loc,
3870                                 AlignmentSource Source = AlignmentSource::Type,
3871                                 bool isNontemporal = false) {
3872     return EmitLoadOfScalar(Addr, Volatile, Ty, Loc, LValueBaseInfo(Source),
3873                             CGM.getTBAAAccessInfo(Ty), isNontemporal);
3874   }
3875 
3876   llvm::Value *EmitLoadOfScalar(Address Addr, bool Volatile, QualType Ty,
3877                                 SourceLocation Loc, LValueBaseInfo BaseInfo,
3878                                 TBAAAccessInfo TBAAInfo,
3879                                 bool isNontemporal = false);
3880 
3881   /// EmitLoadOfScalar - Load a scalar value from an address, taking
3882   /// care to appropriately convert from the memory representation to
3883   /// the LLVM value representation.  The l-value must be a simple
3884   /// l-value.
3885   llvm::Value *EmitLoadOfScalar(LValue lvalue, SourceLocation Loc);
3886 
3887   /// EmitStoreOfScalar - Store a scalar value to an address, taking
3888   /// care to appropriately convert from the memory representation to
3889   /// the LLVM value representation.
3890   void EmitStoreOfScalar(llvm::Value *Value, Address Addr,
3891                          bool Volatile, QualType Ty,
3892                          AlignmentSource Source = AlignmentSource::Type,
3893                          bool isInit = false, bool isNontemporal = false) {
3894     EmitStoreOfScalar(Value, Addr, Volatile, Ty, LValueBaseInfo(Source),
3895                       CGM.getTBAAAccessInfo(Ty), isInit, isNontemporal);
3896   }
3897 
3898   void EmitStoreOfScalar(llvm::Value *Value, Address Addr,
3899                          bool Volatile, QualType Ty,
3900                          LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo,
3901                          bool isInit = false, bool isNontemporal = false);
3902 
3903   /// EmitStoreOfScalar - Store a scalar value to an address, taking
3904   /// care to appropriately convert from the memory representation to
3905   /// the LLVM value representation.  The l-value must be a simple
3906   /// l-value.  The isInit flag indicates whether this is an initialization.
3907   /// If so, atomic qualifiers are ignored and the store is always non-atomic.
3908   void EmitStoreOfScalar(llvm::Value *value, LValue lvalue, bool isInit=false);
3909 
3910   /// EmitLoadOfLValue - Given an expression that represents a value lvalue,
3911   /// this method emits the address of the lvalue, then loads the result as an
3912   /// rvalue, returning the rvalue.
3913   RValue EmitLoadOfLValue(LValue V, SourceLocation Loc);
3914   RValue EmitLoadOfExtVectorElementLValue(LValue V);
3915   RValue EmitLoadOfBitfieldLValue(LValue LV, SourceLocation Loc);
3916   RValue EmitLoadOfGlobalRegLValue(LValue LV);
3917 
3918   /// EmitStoreThroughLValue - Store the specified rvalue into the specified
3919   /// lvalue, where both are guaranteed to the have the same type, and that type
3920   /// is 'Ty'.
3921   void EmitStoreThroughLValue(RValue Src, LValue Dst, bool isInit = false);
3922   void EmitStoreThroughExtVectorComponentLValue(RValue Src, LValue Dst);
3923   void EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst);
3924 
3925   /// EmitStoreThroughBitfieldLValue - Store Src into Dst with same constraints
3926   /// as EmitStoreThroughLValue.
3927   ///
3928   /// \param Result [out] - If non-null, this will be set to a Value* for the
3929   /// bit-field contents after the store, appropriate for use as the result of
3930   /// an assignment to the bit-field.
3931   void EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
3932                                       llvm::Value **Result=nullptr);
3933 
3934   /// Emit an l-value for an assignment (simple or compound) of complex type.
3935   LValue EmitComplexAssignmentLValue(const BinaryOperator *E);
3936   LValue EmitComplexCompoundAssignmentLValue(const CompoundAssignOperator *E);
3937   LValue EmitScalarCompoundAssignWithComplex(const CompoundAssignOperator *E,
3938                                              llvm::Value *&Result);
3939 
3940   // Note: only available for agg return types
3941   LValue EmitBinaryOperatorLValue(const BinaryOperator *E);
3942   LValue EmitCompoundAssignmentLValue(const CompoundAssignOperator *E);
3943   // Note: only available for agg return types
3944   LValue EmitCallExprLValue(const CallExpr *E);
3945   // Note: only available for agg return types
3946   LValue EmitVAArgExprLValue(const VAArgExpr *E);
3947   LValue EmitDeclRefLValue(const DeclRefExpr *E);
3948   LValue EmitStringLiteralLValue(const StringLiteral *E);
3949   LValue EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E);
3950   LValue EmitPredefinedLValue(const PredefinedExpr *E);
3951   LValue EmitUnaryOpLValue(const UnaryOperator *E);
3952   LValue EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3953                                 bool Accessed = false);
3954   LValue EmitMatrixSubscriptExpr(const MatrixSubscriptExpr *E);
3955   LValue EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3956                                  bool IsLowerBound = true);
3957   LValue EmitExtVectorElementExpr(const ExtVectorElementExpr *E);
3958   LValue EmitMemberExpr(const MemberExpr *E);
3959   LValue EmitObjCIsaExpr(const ObjCIsaExpr *E);
3960   LValue EmitCompoundLiteralLValue(const CompoundLiteralExpr *E);
3961   LValue EmitInitListLValue(const InitListExpr *E);
3962   void EmitIgnoredConditionalOperator(const AbstractConditionalOperator *E);
3963   LValue EmitConditionalOperatorLValue(const AbstractConditionalOperator *E);
3964   LValue EmitCastLValue(const CastExpr *E);
3965   LValue EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E);
3966   LValue EmitOpaqueValueLValue(const OpaqueValueExpr *e);
3967 
3968   Address EmitExtVectorElementLValue(LValue V);
3969 
3970   RValue EmitRValueForField(LValue LV, const FieldDecl *FD, SourceLocation Loc);
3971 
3972   Address EmitArrayToPointerDecay(const Expr *Array,
3973                                   LValueBaseInfo *BaseInfo = nullptr,
3974                                   TBAAAccessInfo *TBAAInfo = nullptr);
3975 
3976   class ConstantEmission {
3977     llvm::PointerIntPair<llvm::Constant*, 1, bool> ValueAndIsReference;
3978     ConstantEmission(llvm::Constant *C, bool isReference)
3979       : ValueAndIsReference(C, isReference) {}
3980   public:
3981     ConstantEmission() {}
3982     static ConstantEmission forReference(llvm::Constant *C) {
3983       return ConstantEmission(C, true);
3984     }
3985     static ConstantEmission forValue(llvm::Constant *C) {
3986       return ConstantEmission(C, false);
3987     }
3988 
3989     explicit operator bool() const {
3990       return ValueAndIsReference.getOpaqueValue() != nullptr;
3991     }
3992 
3993     bool isReference() const { return ValueAndIsReference.getInt(); }
3994     LValue getReferenceLValue(CodeGenFunction &CGF, Expr *refExpr) const {
3995       assert(isReference());
3996       return CGF.MakeNaturalAlignAddrLValue(ValueAndIsReference.getPointer(),
3997                                             refExpr->getType());
3998     }
3999 
4000     llvm::Constant *getValue() const {
4001       assert(!isReference());
4002       return ValueAndIsReference.getPointer();
4003     }
4004   };
4005 
4006   ConstantEmission tryEmitAsConstant(DeclRefExpr *refExpr);
4007   ConstantEmission tryEmitAsConstant(const MemberExpr *ME);
4008   llvm::Value *emitScalarConstant(const ConstantEmission &Constant, Expr *E);
4009 
4010   RValue EmitPseudoObjectRValue(const PseudoObjectExpr *e,
4011                                 AggValueSlot slot = AggValueSlot::ignored());
4012   LValue EmitPseudoObjectLValue(const PseudoObjectExpr *e);
4013 
4014   llvm::Value *EmitIvarOffset(const ObjCInterfaceDecl *Interface,
4015                               const ObjCIvarDecl *Ivar);
4016   llvm::Value *EmitIvarOffsetAsPointerDiff(const ObjCInterfaceDecl *Interface,
4017                                            const ObjCIvarDecl *Ivar);
4018   LValue EmitLValueForField(LValue Base, const FieldDecl* Field);
4019   LValue EmitLValueForLambdaField(const FieldDecl *Field);
4020 
4021   /// EmitLValueForFieldInitialization - Like EmitLValueForField, except that
4022   /// if the Field is a reference, this will return the address of the reference
4023   /// and not the address of the value stored in the reference.
4024   LValue EmitLValueForFieldInitialization(LValue Base,
4025                                           const FieldDecl* Field);
4026 
4027   LValue EmitLValueForIvar(QualType ObjectTy,
4028                            llvm::Value* Base, const ObjCIvarDecl *Ivar,
4029                            unsigned CVRQualifiers);
4030 
4031   LValue EmitCXXConstructLValue(const CXXConstructExpr *E);
4032   LValue EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E);
4033   LValue EmitCXXTypeidLValue(const CXXTypeidExpr *E);
4034   LValue EmitCXXUuidofLValue(const CXXUuidofExpr *E);
4035 
4036   LValue EmitObjCMessageExprLValue(const ObjCMessageExpr *E);
4037   LValue EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E);
4038   LValue EmitStmtExprLValue(const StmtExpr *E);
4039   LValue EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E);
4040   LValue EmitObjCSelectorLValue(const ObjCSelectorExpr *E);
4041   void   EmitDeclRefExprDbgValue(const DeclRefExpr *E, const APValue &Init);
4042 
4043   //===--------------------------------------------------------------------===//
4044   //                         Scalar Expression Emission
4045   //===--------------------------------------------------------------------===//
4046 
4047   /// EmitCall - Generate a call of the given function, expecting the given
4048   /// result type, and using the given argument list which specifies both the
4049   /// LLVM arguments and the types they were derived from.
4050   RValue EmitCall(const CGFunctionInfo &CallInfo, const CGCallee &Callee,
4051                   ReturnValueSlot ReturnValue, const CallArgList &Args,
4052                   llvm::CallBase **callOrInvoke, bool IsMustTail,
4053                   SourceLocation Loc);
4054   RValue EmitCall(const CGFunctionInfo &CallInfo, const CGCallee &Callee,
4055                   ReturnValueSlot ReturnValue, const CallArgList &Args,
4056                   llvm::CallBase **callOrInvoke = nullptr,
4057                   bool IsMustTail = false) {
4058     return EmitCall(CallInfo, Callee, ReturnValue, Args, callOrInvoke,
4059                     IsMustTail, SourceLocation());
4060   }
4061   RValue EmitCall(QualType FnType, const CGCallee &Callee, const CallExpr *E,
4062                   ReturnValueSlot ReturnValue, llvm::Value *Chain = nullptr);
4063   RValue EmitCallExpr(const CallExpr *E,
4064                       ReturnValueSlot ReturnValue = ReturnValueSlot());
4065   RValue EmitSimpleCallExpr(const CallExpr *E, ReturnValueSlot ReturnValue);
4066   CGCallee EmitCallee(const Expr *E);
4067 
4068   void checkTargetFeatures(const CallExpr *E, const FunctionDecl *TargetDecl);
4069   void checkTargetFeatures(SourceLocation Loc, const FunctionDecl *TargetDecl);
4070 
4071   llvm::CallInst *EmitRuntimeCall(llvm::FunctionCallee callee,
4072                                   const Twine &name = "");
4073   llvm::CallInst *EmitRuntimeCall(llvm::FunctionCallee callee,
4074                                   ArrayRef<llvm::Value *> args,
4075                                   const Twine &name = "");
4076   llvm::CallInst *EmitNounwindRuntimeCall(llvm::FunctionCallee callee,
4077                                           const Twine &name = "");
4078   llvm::CallInst *EmitNounwindRuntimeCall(llvm::FunctionCallee callee,
4079                                           ArrayRef<llvm::Value *> args,
4080                                           const Twine &name = "");
4081 
4082   SmallVector<llvm::OperandBundleDef, 1>
4083   getBundlesForFunclet(llvm::Value *Callee);
4084 
4085   llvm::CallBase *EmitCallOrInvoke(llvm::FunctionCallee Callee,
4086                                    ArrayRef<llvm::Value *> Args,
4087                                    const Twine &Name = "");
4088   llvm::CallBase *EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee,
4089                                           ArrayRef<llvm::Value *> args,
4090                                           const Twine &name = "");
4091   llvm::CallBase *EmitRuntimeCallOrInvoke(llvm::FunctionCallee callee,
4092                                           const Twine &name = "");
4093   void EmitNoreturnRuntimeCallOrInvoke(llvm::FunctionCallee callee,
4094                                        ArrayRef<llvm::Value *> args);
4095 
4096   CGCallee BuildAppleKextVirtualCall(const CXXMethodDecl *MD,
4097                                      NestedNameSpecifier *Qual,
4098                                      llvm::Type *Ty);
4099 
4100   CGCallee BuildAppleKextVirtualDestructorCall(const CXXDestructorDecl *DD,
4101                                                CXXDtorType Type,
4102                                                const CXXRecordDecl *RD);
4103 
4104   // Return the copy constructor name with the prefix "__copy_constructor_"
4105   // removed.
4106   static std::string getNonTrivialCopyConstructorStr(QualType QT,
4107                                                      CharUnits Alignment,
4108                                                      bool IsVolatile,
4109                                                      ASTContext &Ctx);
4110 
4111   // Return the destructor name with the prefix "__destructor_" removed.
4112   static std::string getNonTrivialDestructorStr(QualType QT,
4113                                                 CharUnits Alignment,
4114                                                 bool IsVolatile,
4115                                                 ASTContext &Ctx);
4116 
4117   // These functions emit calls to the special functions of non-trivial C
4118   // structs.
4119   void defaultInitNonTrivialCStructVar(LValue Dst);
4120   void callCStructDefaultConstructor(LValue Dst);
4121   void callCStructDestructor(LValue Dst);
4122   void callCStructCopyConstructor(LValue Dst, LValue Src);
4123   void callCStructMoveConstructor(LValue Dst, LValue Src);
4124   void callCStructCopyAssignmentOperator(LValue Dst, LValue Src);
4125   void callCStructMoveAssignmentOperator(LValue Dst, LValue Src);
4126 
4127   RValue
4128   EmitCXXMemberOrOperatorCall(const CXXMethodDecl *Method,
4129                               const CGCallee &Callee,
4130                               ReturnValueSlot ReturnValue, llvm::Value *This,
4131                               llvm::Value *ImplicitParam,
4132                               QualType ImplicitParamTy, const CallExpr *E,
4133                               CallArgList *RtlArgs);
4134   RValue EmitCXXDestructorCall(GlobalDecl Dtor, const CGCallee &Callee,
4135                                llvm::Value *This, QualType ThisTy,
4136                                llvm::Value *ImplicitParam,
4137                                QualType ImplicitParamTy, const CallExpr *E);
4138   RValue EmitCXXMemberCallExpr(const CXXMemberCallExpr *E,
4139                                ReturnValueSlot ReturnValue);
4140   RValue EmitCXXMemberOrOperatorMemberCallExpr(const CallExpr *CE,
4141                                                const CXXMethodDecl *MD,
4142                                                ReturnValueSlot ReturnValue,
4143                                                bool HasQualifier,
4144                                                NestedNameSpecifier *Qualifier,
4145                                                bool IsArrow, const Expr *Base);
4146   // Compute the object pointer.
4147   Address EmitCXXMemberDataPointerAddress(const Expr *E, Address base,
4148                                           llvm::Value *memberPtr,
4149                                           const MemberPointerType *memberPtrType,
4150                                           LValueBaseInfo *BaseInfo = nullptr,
4151                                           TBAAAccessInfo *TBAAInfo = nullptr);
4152   RValue EmitCXXMemberPointerCallExpr(const CXXMemberCallExpr *E,
4153                                       ReturnValueSlot ReturnValue);
4154 
4155   RValue EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
4156                                        const CXXMethodDecl *MD,
4157                                        ReturnValueSlot ReturnValue);
4158   RValue EmitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E);
4159 
4160   RValue EmitCUDAKernelCallExpr(const CUDAKernelCallExpr *E,
4161                                 ReturnValueSlot ReturnValue);
4162 
4163   RValue EmitNVPTXDevicePrintfCallExpr(const CallExpr *E);
4164   RValue EmitAMDGPUDevicePrintfCallExpr(const CallExpr *E);
4165   RValue EmitOpenMPDevicePrintfCallExpr(const CallExpr *E);
4166 
4167   RValue EmitBuiltinExpr(const GlobalDecl GD, unsigned BuiltinID,
4168                          const CallExpr *E, ReturnValueSlot ReturnValue);
4169 
4170   RValue emitRotate(const CallExpr *E, bool IsRotateRight);
4171 
4172   /// Emit IR for __builtin_os_log_format.
4173   RValue emitBuiltinOSLogFormat(const CallExpr &E);
4174 
4175   /// Emit IR for __builtin_is_aligned.
4176   RValue EmitBuiltinIsAligned(const CallExpr *E);
4177   /// Emit IR for __builtin_align_up/__builtin_align_down.
4178   RValue EmitBuiltinAlignTo(const CallExpr *E, bool AlignUp);
4179 
4180   llvm::Function *generateBuiltinOSLogHelperFunction(
4181       const analyze_os_log::OSLogBufferLayout &Layout,
4182       CharUnits BufferAlignment);
4183 
4184   RValue EmitBlockCallExpr(const CallExpr *E, ReturnValueSlot ReturnValue);
4185 
4186   /// EmitTargetBuiltinExpr - Emit the given builtin call. Returns 0 if the call
4187   /// is unhandled by the current target.
4188   llvm::Value *EmitTargetBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4189                                      ReturnValueSlot ReturnValue);
4190 
4191   llvm::Value *EmitAArch64CompareBuiltinExpr(llvm::Value *Op, llvm::Type *Ty,
4192                                              const llvm::CmpInst::Predicate Fp,
4193                                              const llvm::CmpInst::Predicate Ip,
4194                                              const llvm::Twine &Name = "");
4195   llvm::Value *EmitARMBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4196                                   ReturnValueSlot ReturnValue,
4197                                   llvm::Triple::ArchType Arch);
4198   llvm::Value *EmitARMMVEBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4199                                      ReturnValueSlot ReturnValue,
4200                                      llvm::Triple::ArchType Arch);
4201   llvm::Value *EmitARMCDEBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4202                                      ReturnValueSlot ReturnValue,
4203                                      llvm::Triple::ArchType Arch);
4204   llvm::Value *EmitCMSEClearRecord(llvm::Value *V, llvm::IntegerType *ITy,
4205                                    QualType RTy);
4206   llvm::Value *EmitCMSEClearRecord(llvm::Value *V, llvm::ArrayType *ATy,
4207                                    QualType RTy);
4208 
4209   llvm::Value *EmitCommonNeonBuiltinExpr(unsigned BuiltinID,
4210                                          unsigned LLVMIntrinsic,
4211                                          unsigned AltLLVMIntrinsic,
4212                                          const char *NameHint,
4213                                          unsigned Modifier,
4214                                          const CallExpr *E,
4215                                          SmallVectorImpl<llvm::Value *> &Ops,
4216                                          Address PtrOp0, Address PtrOp1,
4217                                          llvm::Triple::ArchType Arch);
4218 
4219   llvm::Function *LookupNeonLLVMIntrinsic(unsigned IntrinsicID,
4220                                           unsigned Modifier, llvm::Type *ArgTy,
4221                                           const CallExpr *E);
4222   llvm::Value *EmitNeonCall(llvm::Function *F,
4223                             SmallVectorImpl<llvm::Value*> &O,
4224                             const char *name,
4225                             unsigned shift = 0, bool rightshift = false);
4226   llvm::Value *EmitNeonSplat(llvm::Value *V, llvm::Constant *Idx,
4227                              const llvm::ElementCount &Count);
4228   llvm::Value *EmitNeonSplat(llvm::Value *V, llvm::Constant *Idx);
4229   llvm::Value *EmitNeonShiftVector(llvm::Value *V, llvm::Type *Ty,
4230                                    bool negateForRightShift);
4231   llvm::Value *EmitNeonRShiftImm(llvm::Value *Vec, llvm::Value *Amt,
4232                                  llvm::Type *Ty, bool usgn, const char *name);
4233   llvm::Value *vectorWrapScalar16(llvm::Value *Op);
4234   /// SVEBuiltinMemEltTy - Returns the memory element type for this memory
4235   /// access builtin.  Only required if it can't be inferred from the base
4236   /// pointer operand.
4237   llvm::Type *SVEBuiltinMemEltTy(const SVETypeFlags &TypeFlags);
4238 
4239   SmallVector<llvm::Type *, 2>
4240   getSVEOverloadTypes(const SVETypeFlags &TypeFlags, llvm::Type *ReturnType,
4241                       ArrayRef<llvm::Value *> Ops);
4242   llvm::Type *getEltType(const SVETypeFlags &TypeFlags);
4243   llvm::ScalableVectorType *getSVEType(const SVETypeFlags &TypeFlags);
4244   llvm::ScalableVectorType *getSVEPredType(const SVETypeFlags &TypeFlags);
4245   llvm::Value *EmitSVETupleSetOrGet(const SVETypeFlags &TypeFlags,
4246                                     llvm::Type *ReturnType,
4247                                     ArrayRef<llvm::Value *> Ops);
4248   llvm::Value *EmitSVETupleCreate(const SVETypeFlags &TypeFlags,
4249                                   llvm::Type *ReturnType,
4250                                   ArrayRef<llvm::Value *> Ops);
4251   llvm::Value *EmitSVEAllTruePred(const SVETypeFlags &TypeFlags);
4252   llvm::Value *EmitSVEDupX(llvm::Value *Scalar);
4253   llvm::Value *EmitSVEDupX(llvm::Value *Scalar, llvm::Type *Ty);
4254   llvm::Value *EmitSVEReinterpret(llvm::Value *Val, llvm::Type *Ty);
4255   llvm::Value *EmitSVEPMull(const SVETypeFlags &TypeFlags,
4256                             llvm::SmallVectorImpl<llvm::Value *> &Ops,
4257                             unsigned BuiltinID);
4258   llvm::Value *EmitSVEMovl(const SVETypeFlags &TypeFlags,
4259                            llvm::ArrayRef<llvm::Value *> Ops,
4260                            unsigned BuiltinID);
4261   llvm::Value *EmitSVEPredicateCast(llvm::Value *Pred,
4262                                     llvm::ScalableVectorType *VTy);
4263   llvm::Value *EmitSVEGatherLoad(const SVETypeFlags &TypeFlags,
4264                                  llvm::SmallVectorImpl<llvm::Value *> &Ops,
4265                                  unsigned IntID);
4266   llvm::Value *EmitSVEScatterStore(const SVETypeFlags &TypeFlags,
4267                                    llvm::SmallVectorImpl<llvm::Value *> &Ops,
4268                                    unsigned IntID);
4269   llvm::Value *EmitSVEMaskedLoad(const CallExpr *, llvm::Type *ReturnTy,
4270                                  SmallVectorImpl<llvm::Value *> &Ops,
4271                                  unsigned BuiltinID, bool IsZExtReturn);
4272   llvm::Value *EmitSVEMaskedStore(const CallExpr *,
4273                                   SmallVectorImpl<llvm::Value *> &Ops,
4274                                   unsigned BuiltinID);
4275   llvm::Value *EmitTileslice(llvm::Value *Offset, llvm::Value *Base);
4276   llvm::Value *EmitSVEPrefetchLoad(const SVETypeFlags &TypeFlags,
4277                                    SmallVectorImpl<llvm::Value *> &Ops,
4278                                    unsigned BuiltinID);
4279   llvm::Value *EmitSVEGatherPrefetch(const SVETypeFlags &TypeFlags,
4280                                      SmallVectorImpl<llvm::Value *> &Ops,
4281                                      unsigned IntID);
4282   llvm::Value *EmitSVEStructLoad(const SVETypeFlags &TypeFlags,
4283                                  SmallVectorImpl<llvm::Value *> &Ops,
4284                                  unsigned IntID);
4285   llvm::Value *EmitSVEStructStore(const SVETypeFlags &TypeFlags,
4286                                   SmallVectorImpl<llvm::Value *> &Ops,
4287                                   unsigned IntID);
4288   llvm::Value *EmitAArch64SVEBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4289 
4290   llvm::Value *EmitSMELd1St1(SVETypeFlags TypeFlags,
4291                              llvm::SmallVectorImpl<llvm::Value *> &Ops,
4292                              unsigned IntID);
4293   llvm::Value *EmitSMEReadWrite(SVETypeFlags TypeFlags,
4294                                 llvm::SmallVectorImpl<llvm::Value *> &Ops,
4295                                 unsigned IntID);
4296   llvm::Value *EmitSMEZero(SVETypeFlags TypeFlags,
4297                            llvm::SmallVectorImpl<llvm::Value *> &Ops,
4298                            unsigned IntID);
4299   llvm::Value *EmitSMELdrStr(SVETypeFlags TypeFlags,
4300                              llvm::SmallVectorImpl<llvm::Value *> &Ops,
4301                              unsigned IntID);
4302   llvm::Value *EmitAArch64SMEBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4303 
4304   llvm::Value *EmitAArch64BuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4305                                       llvm::Triple::ArchType Arch);
4306   llvm::Value *EmitBPFBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4307 
4308   llvm::Value *BuildVector(ArrayRef<llvm::Value*> Ops);
4309   llvm::Value *EmitX86BuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4310   llvm::Value *EmitPPCBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4311   llvm::Value *EmitAMDGPUBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4312   llvm::Value *EmitSystemZBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4313   llvm::Value *EmitNVPTXBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4314   llvm::Value *EmitWebAssemblyBuiltinExpr(unsigned BuiltinID,
4315                                           const CallExpr *E);
4316   llvm::Value *EmitHexagonBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4317   llvm::Value *EmitRISCVBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
4318                                     ReturnValueSlot ReturnValue);
4319   llvm::Value *EmitLoongArchBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
4320   void ProcessOrderScopeAMDGCN(llvm::Value *Order, llvm::Value *Scope,
4321                                llvm::AtomicOrdering &AO,
4322                                llvm::SyncScope::ID &SSID);
4323 
4324   enum class MSVCIntrin;
4325   llvm::Value *EmitMSVCBuiltinExpr(MSVCIntrin BuiltinID, const CallExpr *E);
4326 
4327   llvm::Value *EmitBuiltinAvailable(const VersionTuple &Version);
4328 
4329   llvm::Value *EmitObjCProtocolExpr(const ObjCProtocolExpr *E);
4330   llvm::Value *EmitObjCStringLiteral(const ObjCStringLiteral *E);
4331   llvm::Value *EmitObjCBoxedExpr(const ObjCBoxedExpr *E);
4332   llvm::Value *EmitObjCArrayLiteral(const ObjCArrayLiteral *E);
4333   llvm::Value *EmitObjCDictionaryLiteral(const ObjCDictionaryLiteral *E);
4334   llvm::Value *EmitObjCCollectionLiteral(const Expr *E,
4335                                 const ObjCMethodDecl *MethodWithObjects);
4336   llvm::Value *EmitObjCSelectorExpr(const ObjCSelectorExpr *E);
4337   RValue EmitObjCMessageExpr(const ObjCMessageExpr *E,
4338                              ReturnValueSlot Return = ReturnValueSlot());
4339 
4340   /// Retrieves the default cleanup kind for an ARC cleanup.
4341   /// Except under -fobjc-arc-eh, ARC cleanups are normal-only.
4342   CleanupKind getARCCleanupKind() {
4343     return CGM.getCodeGenOpts().ObjCAutoRefCountExceptions
4344              ? NormalAndEHCleanup : NormalCleanup;
4345   }
4346 
4347   // ARC primitives.
4348   void EmitARCInitWeak(Address addr, llvm::Value *value);
4349   void EmitARCDestroyWeak(Address addr);
4350   llvm::Value *EmitARCLoadWeak(Address addr);
4351   llvm::Value *EmitARCLoadWeakRetained(Address addr);
4352   llvm::Value *EmitARCStoreWeak(Address addr, llvm::Value *value, bool ignored);
4353   void emitARCCopyAssignWeak(QualType Ty, Address DstAddr, Address SrcAddr);
4354   void emitARCMoveAssignWeak(QualType Ty, Address DstAddr, Address SrcAddr);
4355   void EmitARCCopyWeak(Address dst, Address src);
4356   void EmitARCMoveWeak(Address dst, Address src);
4357   llvm::Value *EmitARCRetainAutorelease(QualType type, llvm::Value *value);
4358   llvm::Value *EmitARCRetainAutoreleaseNonBlock(llvm::Value *value);
4359   llvm::Value *EmitARCStoreStrong(LValue lvalue, llvm::Value *value,
4360                                   bool resultIgnored);
4361   llvm::Value *EmitARCStoreStrongCall(Address addr, llvm::Value *value,
4362                                       bool resultIgnored);
4363   llvm::Value *EmitARCRetain(QualType type, llvm::Value *value);
4364   llvm::Value *EmitARCRetainNonBlock(llvm::Value *value);
4365   llvm::Value *EmitARCRetainBlock(llvm::Value *value, bool mandatory);
4366   void EmitARCDestroyStrong(Address addr, ARCPreciseLifetime_t precise);
4367   void EmitARCRelease(llvm::Value *value, ARCPreciseLifetime_t precise);
4368   llvm::Value *EmitARCAutorelease(llvm::Value *value);
4369   llvm::Value *EmitARCAutoreleaseReturnValue(llvm::Value *value);
4370   llvm::Value *EmitARCRetainAutoreleaseReturnValue(llvm::Value *value);
4371   llvm::Value *EmitARCRetainAutoreleasedReturnValue(llvm::Value *value);
4372   llvm::Value *EmitARCUnsafeClaimAutoreleasedReturnValue(llvm::Value *value);
4373 
4374   llvm::Value *EmitObjCAutorelease(llvm::Value *value, llvm::Type *returnType);
4375   llvm::Value *EmitObjCRetainNonBlock(llvm::Value *value,
4376                                       llvm::Type *returnType);
4377   void EmitObjCRelease(llvm::Value *value, ARCPreciseLifetime_t precise);
4378 
4379   std::pair<LValue,llvm::Value*>
4380   EmitARCStoreAutoreleasing(const BinaryOperator *e);
4381   std::pair<LValue,llvm::Value*>
4382   EmitARCStoreStrong(const BinaryOperator *e, bool ignored);
4383   std::pair<LValue,llvm::Value*>
4384   EmitARCStoreUnsafeUnretained(const BinaryOperator *e, bool ignored);
4385 
4386   llvm::Value *EmitObjCAlloc(llvm::Value *value,
4387                              llvm::Type *returnType);
4388   llvm::Value *EmitObjCAllocWithZone(llvm::Value *value,
4389                                      llvm::Type *returnType);
4390   llvm::Value *EmitObjCAllocInit(llvm::Value *value, llvm::Type *resultType);
4391 
4392   llvm::Value *EmitObjCThrowOperand(const Expr *expr);
4393   llvm::Value *EmitObjCConsumeObject(QualType T, llvm::Value *Ptr);
4394   llvm::Value *EmitObjCExtendObjectLifetime(QualType T, llvm::Value *Ptr);
4395 
4396   llvm::Value *EmitARCExtendBlockObject(const Expr *expr);
4397   llvm::Value *EmitARCReclaimReturnedObject(const Expr *e,
4398                                             bool allowUnsafeClaim);
4399   llvm::Value *EmitARCRetainScalarExpr(const Expr *expr);
4400   llvm::Value *EmitARCRetainAutoreleaseScalarExpr(const Expr *expr);
4401   llvm::Value *EmitARCUnsafeUnretainedScalarExpr(const Expr *expr);
4402 
4403   void EmitARCIntrinsicUse(ArrayRef<llvm::Value*> values);
4404 
4405   void EmitARCNoopIntrinsicUse(ArrayRef<llvm::Value *> values);
4406 
4407   static Destroyer destroyARCStrongImprecise;
4408   static Destroyer destroyARCStrongPrecise;
4409   static Destroyer destroyARCWeak;
4410   static Destroyer emitARCIntrinsicUse;
4411   static Destroyer destroyNonTrivialCStruct;
4412 
4413   void EmitObjCAutoreleasePoolPop(llvm::Value *Ptr);
4414   llvm::Value *EmitObjCAutoreleasePoolPush();
4415   llvm::Value *EmitObjCMRRAutoreleasePoolPush();
4416   void EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr);
4417   void EmitObjCMRRAutoreleasePoolPop(llvm::Value *Ptr);
4418 
4419   /// Emits a reference binding to the passed in expression.
4420   RValue EmitReferenceBindingToExpr(const Expr *E);
4421 
4422   //===--------------------------------------------------------------------===//
4423   //                           Expression Emission
4424   //===--------------------------------------------------------------------===//
4425 
4426   // Expressions are broken into three classes: scalar, complex, aggregate.
4427 
4428   /// EmitScalarExpr - Emit the computation of the specified expression of LLVM
4429   /// scalar type, returning the result.
4430   llvm::Value *EmitScalarExpr(const Expr *E , bool IgnoreResultAssign = false);
4431 
4432   /// Emit a conversion from the specified type to the specified destination
4433   /// type, both of which are LLVM scalar types.
4434   llvm::Value *EmitScalarConversion(llvm::Value *Src, QualType SrcTy,
4435                                     QualType DstTy, SourceLocation Loc);
4436 
4437   /// Emit a conversion from the specified complex type to the specified
4438   /// destination type, where the destination type is an LLVM scalar type.
4439   llvm::Value *EmitComplexToScalarConversion(ComplexPairTy Src, QualType SrcTy,
4440                                              QualType DstTy,
4441                                              SourceLocation Loc);
4442 
4443   /// EmitAggExpr - Emit the computation of the specified expression
4444   /// of aggregate type.  The result is computed into the given slot,
4445   /// which may be null to indicate that the value is not needed.
4446   void EmitAggExpr(const Expr *E, AggValueSlot AS);
4447 
4448   /// EmitAggExprToLValue - Emit the computation of the specified expression of
4449   /// aggregate type into a temporary LValue.
4450   LValue EmitAggExprToLValue(const Expr *E);
4451 
4452   /// Build all the stores needed to initialize an aggregate at Dest with the
4453   /// value Val.
4454   void EmitAggregateStore(llvm::Value *Val, Address Dest, bool DestIsVolatile);
4455 
4456   /// EmitExtendGCLifetime - Given a pointer to an Objective-C object,
4457   /// make sure it survives garbage collection until this point.
4458   void EmitExtendGCLifetime(llvm::Value *object);
4459 
4460   /// EmitComplexExpr - Emit the computation of the specified expression of
4461   /// complex type, returning the result.
4462   ComplexPairTy EmitComplexExpr(const Expr *E,
4463                                 bool IgnoreReal = false,
4464                                 bool IgnoreImag = false);
4465 
4466   /// EmitComplexExprIntoLValue - Emit the given expression of complex
4467   /// type and place its result into the specified l-value.
4468   void EmitComplexExprIntoLValue(const Expr *E, LValue dest, bool isInit);
4469 
4470   /// EmitStoreOfComplex - Store a complex number into the specified l-value.
4471   void EmitStoreOfComplex(ComplexPairTy V, LValue dest, bool isInit);
4472 
4473   /// EmitLoadOfComplex - Load a complex number from the specified l-value.
4474   ComplexPairTy EmitLoadOfComplex(LValue src, SourceLocation loc);
4475 
4476   ComplexPairTy EmitPromotedComplexExpr(const Expr *E, QualType PromotionType);
4477   llvm::Value *EmitPromotedScalarExpr(const Expr *E, QualType PromotionType);
4478   ComplexPairTy EmitPromotedValue(ComplexPairTy result, QualType PromotionType);
4479   ComplexPairTy EmitUnPromotedValue(ComplexPairTy result, QualType PromotionType);
4480 
4481   Address emitAddrOfRealComponent(Address complex, QualType complexType);
4482   Address emitAddrOfImagComponent(Address complex, QualType complexType);
4483 
4484   /// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
4485   /// global variable that has already been created for it.  If the initializer
4486   /// has a different type than GV does, this may free GV and return a different
4487   /// one.  Otherwise it just returns GV.
4488   llvm::GlobalVariable *
4489   AddInitializerToStaticVarDecl(const VarDecl &D,
4490                                 llvm::GlobalVariable *GV);
4491 
4492   // Emit an @llvm.invariant.start call for the given memory region.
4493   void EmitInvariantStart(llvm::Constant *Addr, CharUnits Size);
4494 
4495   /// EmitCXXGlobalVarDeclInit - Create the initializer for a C++
4496   /// variable with global storage.
4497   void EmitCXXGlobalVarDeclInit(const VarDecl &D, llvm::GlobalVariable *GV,
4498                                 bool PerformInit);
4499 
4500   llvm::Function *createAtExitStub(const VarDecl &VD, llvm::FunctionCallee Dtor,
4501                                    llvm::Constant *Addr);
4502 
4503   llvm::Function *createTLSAtExitStub(const VarDecl &VD,
4504                                       llvm::FunctionCallee Dtor,
4505                                       llvm::Constant *Addr,
4506                                       llvm::FunctionCallee &AtExit);
4507 
4508   /// Call atexit() with a function that passes the given argument to
4509   /// the given function.
4510   void registerGlobalDtorWithAtExit(const VarDecl &D, llvm::FunctionCallee fn,
4511                                     llvm::Constant *addr);
4512 
4513   /// Call atexit() with function dtorStub.
4514   void registerGlobalDtorWithAtExit(llvm::Constant *dtorStub);
4515 
4516   /// Call unatexit() with function dtorStub.
4517   llvm::Value *unregisterGlobalDtorWithUnAtExit(llvm::Constant *dtorStub);
4518 
4519   /// Emit code in this function to perform a guarded variable
4520   /// initialization.  Guarded initializations are used when it's not
4521   /// possible to prove that an initialization will be done exactly
4522   /// once, e.g. with a static local variable or a static data member
4523   /// of a class template.
4524   void EmitCXXGuardedInit(const VarDecl &D, llvm::GlobalVariable *DeclPtr,
4525                           bool PerformInit);
4526 
4527   enum class GuardKind { VariableGuard, TlsGuard };
4528 
4529   /// Emit a branch to select whether or not to perform guarded initialization.
4530   void EmitCXXGuardedInitBranch(llvm::Value *NeedsInit,
4531                                 llvm::BasicBlock *InitBlock,
4532                                 llvm::BasicBlock *NoInitBlock,
4533                                 GuardKind Kind, const VarDecl *D);
4534 
4535   /// GenerateCXXGlobalInitFunc - Generates code for initializing global
4536   /// variables.
4537   void
4538   GenerateCXXGlobalInitFunc(llvm::Function *Fn,
4539                             ArrayRef<llvm::Function *> CXXThreadLocals,
4540                             ConstantAddress Guard = ConstantAddress::invalid());
4541 
4542   /// GenerateCXXGlobalCleanUpFunc - Generates code for cleaning up global
4543   /// variables.
4544   void GenerateCXXGlobalCleanUpFunc(
4545       llvm::Function *Fn,
4546       ArrayRef<std::tuple<llvm::FunctionType *, llvm::WeakTrackingVH,
4547                           llvm::Constant *>>
4548           DtorsOrStermFinalizers);
4549 
4550   void GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn,
4551                                         const VarDecl *D,
4552                                         llvm::GlobalVariable *Addr,
4553                                         bool PerformInit);
4554 
4555   void EmitCXXConstructExpr(const CXXConstructExpr *E, AggValueSlot Dest);
4556 
4557   void EmitSynthesizedCXXCopyCtor(Address Dest, Address Src, const Expr *Exp);
4558 
4559   void EmitCXXThrowExpr(const CXXThrowExpr *E, bool KeepInsertionPoint = true);
4560 
4561   RValue EmitAtomicExpr(AtomicExpr *E);
4562 
4563   //===--------------------------------------------------------------------===//
4564   //                         Annotations Emission
4565   //===--------------------------------------------------------------------===//
4566 
4567   /// Emit an annotation call (intrinsic).
4568   llvm::Value *EmitAnnotationCall(llvm::Function *AnnotationFn,
4569                                   llvm::Value *AnnotatedVal,
4570                                   StringRef AnnotationStr,
4571                                   SourceLocation Location,
4572                                   const AnnotateAttr *Attr);
4573 
4574   /// Emit local annotations for the local variable V, declared by D.
4575   void EmitVarAnnotations(const VarDecl *D, llvm::Value *V);
4576 
4577   /// Emit field annotations for the given field & value. Returns the
4578   /// annotation result.
4579   Address EmitFieldAnnotations(const FieldDecl *D, Address V);
4580 
4581   //===--------------------------------------------------------------------===//
4582   //                             Internal Helpers
4583   //===--------------------------------------------------------------------===//
4584 
4585   /// ContainsLabel - Return true if the statement contains a label in it.  If
4586   /// this statement is not executed normally, it not containing a label means
4587   /// that we can just remove the code.
4588   static bool ContainsLabel(const Stmt *S, bool IgnoreCaseStmts = false);
4589 
4590   /// containsBreak - Return true if the statement contains a break out of it.
4591   /// If the statement (recursively) contains a switch or loop with a break
4592   /// inside of it, this is fine.
4593   static bool containsBreak(const Stmt *S);
4594 
4595   /// Determine if the given statement might introduce a declaration into the
4596   /// current scope, by being a (possibly-labelled) DeclStmt.
4597   static bool mightAddDeclToScope(const Stmt *S);
4598 
4599   /// ConstantFoldsToSimpleInteger - If the specified expression does not fold
4600   /// to a constant, or if it does but contains a label, return false.  If it
4601   /// constant folds return true and set the boolean result in Result.
4602   bool ConstantFoldsToSimpleInteger(const Expr *Cond, bool &Result,
4603                                     bool AllowLabels = false);
4604 
4605   /// ConstantFoldsToSimpleInteger - If the specified expression does not fold
4606   /// to a constant, or if it does but contains a label, return false.  If it
4607   /// constant folds return true and set the folded value.
4608   bool ConstantFoldsToSimpleInteger(const Expr *Cond, llvm::APSInt &Result,
4609                                     bool AllowLabels = false);
4610 
4611   /// isInstrumentedCondition - Determine whether the given condition is an
4612   /// instrumentable condition (i.e. no "&&" or "||").
4613   static bool isInstrumentedCondition(const Expr *C);
4614 
4615   /// EmitBranchToCounterBlock - Emit a conditional branch to a new block that
4616   /// increments a profile counter based on the semantics of the given logical
4617   /// operator opcode.  This is used to instrument branch condition coverage
4618   /// for logical operators.
4619   void EmitBranchToCounterBlock(const Expr *Cond, BinaryOperator::Opcode LOp,
4620                                 llvm::BasicBlock *TrueBlock,
4621                                 llvm::BasicBlock *FalseBlock,
4622                                 uint64_t TrueCount = 0,
4623                                 Stmt::Likelihood LH = Stmt::LH_None,
4624                                 const Expr *CntrIdx = nullptr);
4625 
4626   /// EmitBranchOnBoolExpr - Emit a branch on a boolean condition (e.g. for an
4627   /// if statement) to the specified blocks.  Based on the condition, this might
4628   /// try to simplify the codegen of the conditional based on the branch.
4629   /// TrueCount should be the number of times we expect the condition to
4630   /// evaluate to true based on PGO data.
4631   void EmitBranchOnBoolExpr(const Expr *Cond, llvm::BasicBlock *TrueBlock,
4632                             llvm::BasicBlock *FalseBlock, uint64_t TrueCount,
4633                             Stmt::Likelihood LH = Stmt::LH_None);
4634 
4635   /// Given an assignment `*LHS = RHS`, emit a test that checks if \p RHS is
4636   /// nonnull, if \p LHS is marked _Nonnull.
4637   void EmitNullabilityCheck(LValue LHS, llvm::Value *RHS, SourceLocation Loc);
4638 
4639   /// An enumeration which makes it easier to specify whether or not an
4640   /// operation is a subtraction.
4641   enum { NotSubtraction = false, IsSubtraction = true };
4642 
4643   /// Same as IRBuilder::CreateInBoundsGEP, but additionally emits a check to
4644   /// detect undefined behavior when the pointer overflow sanitizer is enabled.
4645   /// \p SignedIndices indicates whether any of the GEP indices are signed.
4646   /// \p IsSubtraction indicates whether the expression used to form the GEP
4647   /// is a subtraction.
4648   llvm::Value *EmitCheckedInBoundsGEP(llvm::Type *ElemTy, llvm::Value *Ptr,
4649                                       ArrayRef<llvm::Value *> IdxList,
4650                                       bool SignedIndices,
4651                                       bool IsSubtraction,
4652                                       SourceLocation Loc,
4653                                       const Twine &Name = "");
4654 
4655   /// Specifies which type of sanitizer check to apply when handling a
4656   /// particular builtin.
4657   enum BuiltinCheckKind {
4658     BCK_CTZPassedZero,
4659     BCK_CLZPassedZero,
4660   };
4661 
4662   /// Emits an argument for a call to a builtin. If the builtin sanitizer is
4663   /// enabled, a runtime check specified by \p Kind is also emitted.
4664   llvm::Value *EmitCheckedArgForBuiltin(const Expr *E, BuiltinCheckKind Kind);
4665 
4666   /// Emit a description of a type in a format suitable for passing to
4667   /// a runtime sanitizer handler.
4668   llvm::Constant *EmitCheckTypeDescriptor(QualType T);
4669 
4670   /// Convert a value into a format suitable for passing to a runtime
4671   /// sanitizer handler.
4672   llvm::Value *EmitCheckValue(llvm::Value *V);
4673 
4674   /// Emit a description of a source location in a format suitable for
4675   /// passing to a runtime sanitizer handler.
4676   llvm::Constant *EmitCheckSourceLocation(SourceLocation Loc);
4677 
4678   void EmitKCFIOperandBundle(const CGCallee &Callee,
4679                              SmallVectorImpl<llvm::OperandBundleDef> &Bundles);
4680 
4681   /// Create a basic block that will either trap or call a handler function in
4682   /// the UBSan runtime with the provided arguments, and create a conditional
4683   /// branch to it.
4684   void EmitCheck(ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
4685                  SanitizerHandler Check, ArrayRef<llvm::Constant *> StaticArgs,
4686                  ArrayRef<llvm::Value *> DynamicArgs);
4687 
4688   /// Emit a slow path cross-DSO CFI check which calls __cfi_slowpath
4689   /// if Cond if false.
4690   void EmitCfiSlowPathCheck(SanitizerMask Kind, llvm::Value *Cond,
4691                             llvm::ConstantInt *TypeId, llvm::Value *Ptr,
4692                             ArrayRef<llvm::Constant *> StaticArgs);
4693 
4694   /// Emit a reached-unreachable diagnostic if \p Loc is valid and runtime
4695   /// checking is enabled. Otherwise, just emit an unreachable instruction.
4696   void EmitUnreachable(SourceLocation Loc);
4697 
4698   /// Create a basic block that will call the trap intrinsic, and emit a
4699   /// conditional branch to it, for the -ftrapv checks.
4700   void EmitTrapCheck(llvm::Value *Checked, SanitizerHandler CheckHandlerID);
4701 
4702   /// Emit a call to trap or debugtrap and attach function attribute
4703   /// "trap-func-name" if specified.
4704   llvm::CallInst *EmitTrapCall(llvm::Intrinsic::ID IntrID);
4705 
4706   /// Emit a stub for the cross-DSO CFI check function.
4707   void EmitCfiCheckStub();
4708 
4709   /// Emit a cross-DSO CFI failure handling function.
4710   void EmitCfiCheckFail();
4711 
4712   /// Create a check for a function parameter that may potentially be
4713   /// declared as non-null.
4714   void EmitNonNullArgCheck(RValue RV, QualType ArgType, SourceLocation ArgLoc,
4715                            AbstractCallee AC, unsigned ParmNum);
4716 
4717   /// EmitCallArg - Emit a single call argument.
4718   void EmitCallArg(CallArgList &args, const Expr *E, QualType ArgType);
4719 
4720   /// EmitDelegateCallArg - We are performing a delegate call; that
4721   /// is, the current function is delegating to another one.  Produce
4722   /// a r-value suitable for passing the given parameter.
4723   void EmitDelegateCallArg(CallArgList &args, const VarDecl *param,
4724                            SourceLocation loc);
4725 
4726   /// SetFPAccuracy - Set the minimum required accuracy of the given floating
4727   /// point operation, expressed as the maximum relative error in ulp.
4728   void SetFPAccuracy(llvm::Value *Val, float Accuracy);
4729 
4730   /// Set the minimum required accuracy of the given sqrt operation
4731   /// based on CodeGenOpts.
4732   void SetSqrtFPAccuracy(llvm::Value *Val);
4733 
4734   /// Set the minimum required accuracy of the given sqrt operation based on
4735   /// CodeGenOpts.
4736   void SetDivFPAccuracy(llvm::Value *Val);
4737 
4738   /// Set the codegen fast-math flags.
4739   void SetFastMathFlags(FPOptions FPFeatures);
4740 
4741   // Truncate or extend a boolean vector to the requested number of elements.
4742   llvm::Value *emitBoolVecConversion(llvm::Value *SrcVec,
4743                                      unsigned NumElementsDst,
4744                                      const llvm::Twine &Name = "");
4745 
4746 private:
4747   llvm::MDNode *getRangeForLoadFromType(QualType Ty);
4748   void EmitReturnOfRValue(RValue RV, QualType Ty);
4749 
4750   void deferPlaceholderReplacement(llvm::Instruction *Old, llvm::Value *New);
4751 
4752   llvm::SmallVector<std::pair<llvm::WeakTrackingVH, llvm::Value *>, 4>
4753       DeferredReplacements;
4754 
4755   /// Set the address of a local variable.
4756   void setAddrOfLocalVar(const VarDecl *VD, Address Addr) {
4757     assert(!LocalDeclMap.count(VD) && "Decl already exists in LocalDeclMap!");
4758     LocalDeclMap.insert({VD, Addr});
4759   }
4760 
4761   /// ExpandTypeFromArgs - Reconstruct a structure of type \arg Ty
4762   /// from function arguments into \arg Dst. See ABIArgInfo::Expand.
4763   ///
4764   /// \param AI - The first function argument of the expansion.
4765   void ExpandTypeFromArgs(QualType Ty, LValue Dst,
4766                           llvm::Function::arg_iterator &AI);
4767 
4768   /// ExpandTypeToArgs - Expand an CallArg \arg Arg, with the LLVM type for \arg
4769   /// Ty, into individual arguments on the provided vector \arg IRCallArgs,
4770   /// starting at index \arg IRCallArgPos. See ABIArgInfo::Expand.
4771   void ExpandTypeToArgs(QualType Ty, CallArg Arg, llvm::FunctionType *IRFuncTy,
4772                         SmallVectorImpl<llvm::Value *> &IRCallArgs,
4773                         unsigned &IRCallArgPos);
4774 
4775   std::pair<llvm::Value *, llvm::Type *>
4776   EmitAsmInput(const TargetInfo::ConstraintInfo &Info, const Expr *InputExpr,
4777                std::string &ConstraintStr);
4778 
4779   std::pair<llvm::Value *, llvm::Type *>
4780   EmitAsmInputLValue(const TargetInfo::ConstraintInfo &Info, LValue InputValue,
4781                      QualType InputType, std::string &ConstraintStr,
4782                      SourceLocation Loc);
4783 
4784   /// Attempts to statically evaluate the object size of E. If that
4785   /// fails, emits code to figure the size of E out for us. This is
4786   /// pass_object_size aware.
4787   ///
4788   /// If EmittedExpr is non-null, this will use that instead of re-emitting E.
4789   llvm::Value *evaluateOrEmitBuiltinObjectSize(const Expr *E, unsigned Type,
4790                                                llvm::IntegerType *ResType,
4791                                                llvm::Value *EmittedE,
4792                                                bool IsDynamic);
4793 
4794   /// Emits the size of E, as required by __builtin_object_size. This
4795   /// function is aware of pass_object_size parameters, and will act accordingly
4796   /// if E is a parameter with the pass_object_size attribute.
4797   llvm::Value *emitBuiltinObjectSize(const Expr *E, unsigned Type,
4798                                      llvm::IntegerType *ResType,
4799                                      llvm::Value *EmittedE,
4800                                      bool IsDynamic);
4801 
4802   void emitZeroOrPatternForAutoVarInit(QualType type, const VarDecl &D,
4803                                        Address Loc);
4804 
4805 public:
4806   enum class EvaluationOrder {
4807     ///! No language constraints on evaluation order.
4808     Default,
4809     ///! Language semantics require left-to-right evaluation.
4810     ForceLeftToRight,
4811     ///! Language semantics require right-to-left evaluation.
4812     ForceRightToLeft
4813   };
4814 
4815   // Wrapper for function prototype sources. Wraps either a FunctionProtoType or
4816   // an ObjCMethodDecl.
4817   struct PrototypeWrapper {
4818     llvm::PointerUnion<const FunctionProtoType *, const ObjCMethodDecl *> P;
4819 
4820     PrototypeWrapper(const FunctionProtoType *FT) : P(FT) {}
4821     PrototypeWrapper(const ObjCMethodDecl *MD) : P(MD) {}
4822   };
4823 
4824   void EmitCallArgs(CallArgList &Args, PrototypeWrapper Prototype,
4825                     llvm::iterator_range<CallExpr::const_arg_iterator> ArgRange,
4826                     AbstractCallee AC = AbstractCallee(),
4827                     unsigned ParamsToSkip = 0,
4828                     EvaluationOrder Order = EvaluationOrder::Default);
4829 
4830   /// EmitPointerWithAlignment - Given an expression with a pointer type,
4831   /// emit the value and compute our best estimate of the alignment of the
4832   /// pointee.
4833   ///
4834   /// \param BaseInfo - If non-null, this will be initialized with
4835   /// information about the source of the alignment and the may-alias
4836   /// attribute.  Note that this function will conservatively fall back on
4837   /// the type when it doesn't recognize the expression and may-alias will
4838   /// be set to false.
4839   ///
4840   /// One reasonable way to use this information is when there's a language
4841   /// guarantee that the pointer must be aligned to some stricter value, and
4842   /// we're simply trying to ensure that sufficiently obvious uses of under-
4843   /// aligned objects don't get miscompiled; for example, a placement new
4844   /// into the address of a local variable.  In such a case, it's quite
4845   /// reasonable to just ignore the returned alignment when it isn't from an
4846   /// explicit source.
4847   Address
4848   EmitPointerWithAlignment(const Expr *Addr, LValueBaseInfo *BaseInfo = nullptr,
4849                            TBAAAccessInfo *TBAAInfo = nullptr,
4850                            KnownNonNull_t IsKnownNonNull = NotKnownNonNull);
4851 
4852   /// If \p E references a parameter with pass_object_size info or a constant
4853   /// array size modifier, emit the object size divided by the size of \p EltTy.
4854   /// Otherwise return null.
4855   llvm::Value *LoadPassedObjectSize(const Expr *E, QualType EltTy);
4856 
4857   void EmitSanitizerStatReport(llvm::SanitizerStatKind SSK);
4858 
4859   struct MultiVersionResolverOption {
4860     llvm::Function *Function;
4861     struct Conds {
4862       StringRef Architecture;
4863       llvm::SmallVector<StringRef, 8> Features;
4864 
4865       Conds(StringRef Arch, ArrayRef<StringRef> Feats)
4866           : Architecture(Arch), Features(Feats.begin(), Feats.end()) {}
4867     } Conditions;
4868 
4869     MultiVersionResolverOption(llvm::Function *F, StringRef Arch,
4870                                ArrayRef<StringRef> Feats)
4871         : Function(F), Conditions(Arch, Feats) {}
4872   };
4873 
4874   // Emits the body of a multiversion function's resolver. Assumes that the
4875   // options are already sorted in the proper order, with the 'default' option
4876   // last (if it exists).
4877   void EmitMultiVersionResolver(llvm::Function *Resolver,
4878                                 ArrayRef<MultiVersionResolverOption> Options);
4879   void
4880   EmitX86MultiVersionResolver(llvm::Function *Resolver,
4881                               ArrayRef<MultiVersionResolverOption> Options);
4882   void
4883   EmitAArch64MultiVersionResolver(llvm::Function *Resolver,
4884                                   ArrayRef<MultiVersionResolverOption> Options);
4885 
4886 private:
4887   QualType getVarArgType(const Expr *Arg);
4888 
4889   void EmitDeclMetadata();
4890 
4891   BlockByrefHelpers *buildByrefHelpers(llvm::StructType &byrefType,
4892                                   const AutoVarEmission &emission);
4893 
4894   void AddObjCARCExceptionMetadata(llvm::Instruction *Inst);
4895 
4896   llvm::Value *GetValueForARMHint(unsigned BuiltinID);
4897   llvm::Value *EmitX86CpuIs(const CallExpr *E);
4898   llvm::Value *EmitX86CpuIs(StringRef CPUStr);
4899   llvm::Value *EmitX86CpuSupports(const CallExpr *E);
4900   llvm::Value *EmitX86CpuSupports(ArrayRef<StringRef> FeatureStrs);
4901   llvm::Value *EmitX86CpuSupports(uint64_t Mask);
4902   llvm::Value *EmitX86CpuInit();
4903   llvm::Value *FormX86ResolverCondition(const MultiVersionResolverOption &RO);
4904   llvm::Value *EmitAArch64CpuInit();
4905   llvm::Value *
4906   FormAArch64ResolverCondition(const MultiVersionResolverOption &RO);
4907   llvm::Value *EmitAArch64CpuSupports(ArrayRef<StringRef> FeatureStrs);
4908 };
4909 
4910 
4911 inline DominatingLLVMValue::saved_type
4912 DominatingLLVMValue::save(CodeGenFunction &CGF, llvm::Value *value) {
4913   if (!needsSaving(value)) return saved_type(value, false);
4914 
4915   // Otherwise, we need an alloca.
4916   auto align = CharUnits::fromQuantity(
4917       CGF.CGM.getDataLayout().getPrefTypeAlign(value->getType()));
4918   Address alloca =
4919       CGF.CreateTempAlloca(value->getType(), align, "cond-cleanup.save");
4920   CGF.Builder.CreateStore(value, alloca);
4921 
4922   return saved_type(alloca.getPointer(), true);
4923 }
4924 
4925 inline llvm::Value *DominatingLLVMValue::restore(CodeGenFunction &CGF,
4926                                                  saved_type value) {
4927   // If the value says it wasn't saved, trust that it's still dominating.
4928   if (!value.getInt()) return value.getPointer();
4929 
4930   // Otherwise, it should be an alloca instruction, as set up in save().
4931   auto alloca = cast<llvm::AllocaInst>(value.getPointer());
4932   return CGF.Builder.CreateAlignedLoad(alloca->getAllocatedType(), alloca,
4933                                        alloca->getAlign());
4934 }
4935 
4936 }  // end namespace CodeGen
4937 
4938 // Map the LangOption for floating point exception behavior into
4939 // the corresponding enum in the IR.
4940 llvm::fp::ExceptionBehavior
4941 ToConstrainedExceptMD(LangOptions::FPExceptionModeKind Kind);
4942 }  // end namespace clang
4943 
4944 #endif
4945