1 //===-- CodeGenFunction.h - Per-Function state for LLVM CodeGen -*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This is the internal per-function state used for llvm translation.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_CLANG_LIB_CODEGEN_CODEGENFUNCTION_H
15 #define LLVM_CLANG_LIB_CODEGEN_CODEGENFUNCTION_H
16 
17 #include "CGBuilder.h"
18 #include "CGDebugInfo.h"
19 #include "CGLoopInfo.h"
20 #include "CGValue.h"
21 #include "CodeGenModule.h"
22 #include "CodeGenPGO.h"
23 #include "EHScopeStack.h"
24 #include "VarBypassDetector.h"
25 #include "clang/AST/CharUnits.h"
26 #include "clang/AST/ExprCXX.h"
27 #include "clang/AST/ExprObjC.h"
28 #include "clang/AST/ExprOpenMP.h"
29 #include "clang/AST/Type.h"
30 #include "clang/Basic/ABI.h"
31 #include "clang/Basic/CapturedStmt.h"
32 #include "clang/Basic/OpenMPKinds.h"
33 #include "clang/Basic/TargetInfo.h"
34 #include "clang/Frontend/CodeGenOptions.h"
35 #include "llvm/ADT/ArrayRef.h"
36 #include "llvm/ADT/DenseMap.h"
37 #include "llvm/ADT/MapVector.h"
38 #include "llvm/ADT/SmallVector.h"
39 #include "llvm/IR/ValueHandle.h"
40 #include "llvm/Support/Debug.h"
41 #include "llvm/Transforms/Utils/SanitizerStats.h"
42 
43 namespace llvm {
44 class BasicBlock;
45 class LLVMContext;
46 class MDNode;
47 class Module;
48 class SwitchInst;
49 class Twine;
50 class Value;
51 class CallSite;
52 }
53 
54 namespace clang {
55 class ASTContext;
56 class BlockDecl;
57 class CXXDestructorDecl;
58 class CXXForRangeStmt;
59 class CXXTryStmt;
60 class Decl;
61 class LabelDecl;
62 class EnumConstantDecl;
63 class FunctionDecl;
64 class FunctionProtoType;
65 class LabelStmt;
66 class ObjCContainerDecl;
67 class ObjCInterfaceDecl;
68 class ObjCIvarDecl;
69 class ObjCMethodDecl;
70 class ObjCImplementationDecl;
71 class ObjCPropertyImplDecl;
72 class TargetInfo;
73 class VarDecl;
74 class ObjCForCollectionStmt;
75 class ObjCAtTryStmt;
76 class ObjCAtThrowStmt;
77 class ObjCAtSynchronizedStmt;
78 class ObjCAutoreleasePoolStmt;
79 
80 namespace analyze_os_log {
81 class OSLogBufferLayout;
82 }
83 
84 namespace CodeGen {
85 class CodeGenTypes;
86 class CGCallee;
87 class CGFunctionInfo;
88 class CGRecordLayout;
89 class CGBlockInfo;
90 class CGCXXABI;
91 class BlockByrefHelpers;
92 class BlockByrefInfo;
93 class BlockFlags;
94 class BlockFieldFlags;
95 class RegionCodeGenTy;
96 class TargetCodeGenInfo;
97 struct OMPTaskDataTy;
98 struct CGCoroData;
99 
100 /// The kind of evaluation to perform on values of a particular
101 /// type.  Basically, is the code in CGExprScalar, CGExprComplex, or
102 /// CGExprAgg?
103 ///
104 /// TODO: should vectors maybe be split out into their own thing?
105 enum TypeEvaluationKind {
106   TEK_Scalar,
107   TEK_Complex,
108   TEK_Aggregate
109 };
110 
111 #define LIST_SANITIZER_CHECKS                                                  \
112   SANITIZER_CHECK(AddOverflow, add_overflow, 0)                                \
113   SANITIZER_CHECK(BuiltinUnreachable, builtin_unreachable, 0)                  \
114   SANITIZER_CHECK(CFICheckFail, cfi_check_fail, 0)                             \
115   SANITIZER_CHECK(DivremOverflow, divrem_overflow, 0)                          \
116   SANITIZER_CHECK(DynamicTypeCacheMiss, dynamic_type_cache_miss, 0)            \
117   SANITIZER_CHECK(FloatCastOverflow, float_cast_overflow, 0)                   \
118   SANITIZER_CHECK(FunctionTypeMismatch, function_type_mismatch, 0)             \
119   SANITIZER_CHECK(InvalidBuiltin, invalid_builtin, 0)                          \
120   SANITIZER_CHECK(LoadInvalidValue, load_invalid_value, 0)                     \
121   SANITIZER_CHECK(MissingReturn, missing_return, 0)                            \
122   SANITIZER_CHECK(MulOverflow, mul_overflow, 0)                                \
123   SANITIZER_CHECK(NegateOverflow, negate_overflow, 0)                          \
124   SANITIZER_CHECK(NullabilityArg, nullability_arg, 0)                          \
125   SANITIZER_CHECK(NullabilityReturn, nullability_return, 1)                    \
126   SANITIZER_CHECK(NonnullArg, nonnull_arg, 0)                                  \
127   SANITIZER_CHECK(NonnullReturn, nonnull_return, 1)                            \
128   SANITIZER_CHECK(OutOfBounds, out_of_bounds, 0)                               \
129   SANITIZER_CHECK(PointerOverflow, pointer_overflow, 0)                        \
130   SANITIZER_CHECK(ShiftOutOfBounds, shift_out_of_bounds, 0)                    \
131   SANITIZER_CHECK(SubOverflow, sub_overflow, 0)                                \
132   SANITIZER_CHECK(TypeMismatch, type_mismatch, 1)                              \
133   SANITIZER_CHECK(VLABoundNotPositive, vla_bound_not_positive, 0)
134 
135 enum SanitizerHandler {
136 #define SANITIZER_CHECK(Enum, Name, Version) Enum,
137   LIST_SANITIZER_CHECKS
138 #undef SANITIZER_CHECK
139 };
140 
141 /// CodeGenFunction - This class organizes the per-function state that is used
142 /// while generating LLVM code.
143 class CodeGenFunction : public CodeGenTypeCache {
144   CodeGenFunction(const CodeGenFunction &) = delete;
145   void operator=(const CodeGenFunction &) = delete;
146 
147   friend class CGCXXABI;
148 public:
149   /// A jump destination is an abstract label, branching to which may
150   /// require a jump out through normal cleanups.
151   struct JumpDest {
152     JumpDest() : Block(nullptr), ScopeDepth(), Index(0) {}
153     JumpDest(llvm::BasicBlock *Block,
154              EHScopeStack::stable_iterator Depth,
155              unsigned Index)
156       : Block(Block), ScopeDepth(Depth), Index(Index) {}
157 
158     bool isValid() const { return Block != nullptr; }
159     llvm::BasicBlock *getBlock() const { return Block; }
160     EHScopeStack::stable_iterator getScopeDepth() const { return ScopeDepth; }
161     unsigned getDestIndex() const { return Index; }
162 
163     // This should be used cautiously.
164     void setScopeDepth(EHScopeStack::stable_iterator depth) {
165       ScopeDepth = depth;
166     }
167 
168   private:
169     llvm::BasicBlock *Block;
170     EHScopeStack::stable_iterator ScopeDepth;
171     unsigned Index;
172   };
173 
174   CodeGenModule &CGM;  // Per-module state.
175   const TargetInfo &Target;
176 
177   typedef std::pair<llvm::Value *, llvm::Value *> ComplexPairTy;
178   LoopInfoStack LoopStack;
179   CGBuilderTy Builder;
180 
181   // Stores variables for which we can't generate correct lifetime markers
182   // because of jumps.
183   VarBypassDetector Bypasses;
184 
185   // CodeGen lambda for loops and support for ordered clause
186   typedef llvm::function_ref<void(CodeGenFunction &, const OMPLoopDirective &,
187                                   JumpDest)>
188       CodeGenLoopTy;
189   typedef llvm::function_ref<void(CodeGenFunction &, SourceLocation,
190                                   const unsigned, const bool)>
191       CodeGenOrderedTy;
192 
193   // Codegen lambda for loop bounds in worksharing loop constructs
194   typedef llvm::function_ref<std::pair<LValue, LValue>(
195       CodeGenFunction &, const OMPExecutableDirective &S)>
196       CodeGenLoopBoundsTy;
197 
198   // Codegen lambda for loop bounds in dispatch-based loop implementation
199   typedef llvm::function_ref<std::pair<llvm::Value *, llvm::Value *>(
200       CodeGenFunction &, const OMPExecutableDirective &S, Address LB,
201       Address UB)>
202       CodeGenDispatchBoundsTy;
203 
204   /// CGBuilder insert helper. This function is called after an
205   /// instruction is created using Builder.
206   void InsertHelper(llvm::Instruction *I, const llvm::Twine &Name,
207                     llvm::BasicBlock *BB,
208                     llvm::BasicBlock::iterator InsertPt) const;
209 
210   /// CurFuncDecl - Holds the Decl for the current outermost
211   /// non-closure context.
212   const Decl *CurFuncDecl;
213   /// CurCodeDecl - This is the inner-most code context, which includes blocks.
214   const Decl *CurCodeDecl;
215   const CGFunctionInfo *CurFnInfo;
216   QualType FnRetTy;
217   llvm::Function *CurFn;
218 
219   // Holds coroutine data if the current function is a coroutine. We use a
220   // wrapper to manage its lifetime, so that we don't have to define CGCoroData
221   // in this header.
222   struct CGCoroInfo {
223     std::unique_ptr<CGCoroData> Data;
224     CGCoroInfo();
225     ~CGCoroInfo();
226   };
227   CGCoroInfo CurCoro;
228 
229   bool isCoroutine() const {
230     return CurCoro.Data != nullptr;
231   }
232 
233   /// CurGD - The GlobalDecl for the current function being compiled.
234   GlobalDecl CurGD;
235 
236   /// PrologueCleanupDepth - The cleanup depth enclosing all the
237   /// cleanups associated with the parameters.
238   EHScopeStack::stable_iterator PrologueCleanupDepth;
239 
240   /// ReturnBlock - Unified return block.
241   JumpDest ReturnBlock;
242 
243   /// ReturnValue - The temporary alloca to hold the return
244   /// value. This is invalid iff the function has no return value.
245   Address ReturnValue;
246 
247   /// Return true if a label was seen in the current scope.
248   bool hasLabelBeenSeenInCurrentScope() const {
249     if (CurLexicalScope)
250       return CurLexicalScope->hasLabels();
251     return !LabelMap.empty();
252   }
253 
254   /// AllocaInsertPoint - This is an instruction in the entry block before which
255   /// we prefer to insert allocas.
256   llvm::AssertingVH<llvm::Instruction> AllocaInsertPt;
257 
258   /// API for captured statement code generation.
259   class CGCapturedStmtInfo {
260   public:
261     explicit CGCapturedStmtInfo(CapturedRegionKind K = CR_Default)
262         : Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {}
263     explicit CGCapturedStmtInfo(const CapturedStmt &S,
264                                 CapturedRegionKind K = CR_Default)
265       : Kind(K), ThisValue(nullptr), CXXThisFieldDecl(nullptr) {
266 
267       RecordDecl::field_iterator Field =
268         S.getCapturedRecordDecl()->field_begin();
269       for (CapturedStmt::const_capture_iterator I = S.capture_begin(),
270                                                 E = S.capture_end();
271            I != E; ++I, ++Field) {
272         if (I->capturesThis())
273           CXXThisFieldDecl = *Field;
274         else if (I->capturesVariable())
275           CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
276         else if (I->capturesVariableByCopy())
277           CaptureFields[I->getCapturedVar()->getCanonicalDecl()] = *Field;
278       }
279     }
280 
281     virtual ~CGCapturedStmtInfo();
282 
283     CapturedRegionKind getKind() const { return Kind; }
284 
285     virtual void setContextValue(llvm::Value *V) { ThisValue = V; }
286     // Retrieve the value of the context parameter.
287     virtual llvm::Value *getContextValue() const { return ThisValue; }
288 
289     /// Lookup the captured field decl for a variable.
290     virtual const FieldDecl *lookup(const VarDecl *VD) const {
291       return CaptureFields.lookup(VD->getCanonicalDecl());
292     }
293 
294     bool isCXXThisExprCaptured() const { return getThisFieldDecl() != nullptr; }
295     virtual FieldDecl *getThisFieldDecl() const { return CXXThisFieldDecl; }
296 
297     static bool classof(const CGCapturedStmtInfo *) {
298       return true;
299     }
300 
301     /// Emit the captured statement body.
302     virtual void EmitBody(CodeGenFunction &CGF, const Stmt *S) {
303       CGF.incrementProfileCounter(S);
304       CGF.EmitStmt(S);
305     }
306 
307     /// Get the name of the capture helper.
308     virtual StringRef getHelperName() const { return "__captured_stmt"; }
309 
310   private:
311     /// The kind of captured statement being generated.
312     CapturedRegionKind Kind;
313 
314     /// Keep the map between VarDecl and FieldDecl.
315     llvm::SmallDenseMap<const VarDecl *, FieldDecl *> CaptureFields;
316 
317     /// The base address of the captured record, passed in as the first
318     /// argument of the parallel region function.
319     llvm::Value *ThisValue;
320 
321     /// Captured 'this' type.
322     FieldDecl *CXXThisFieldDecl;
323   };
324   CGCapturedStmtInfo *CapturedStmtInfo;
325 
326   /// RAII for correct setting/restoring of CapturedStmtInfo.
327   class CGCapturedStmtRAII {
328   private:
329     CodeGenFunction &CGF;
330     CGCapturedStmtInfo *PrevCapturedStmtInfo;
331   public:
332     CGCapturedStmtRAII(CodeGenFunction &CGF,
333                        CGCapturedStmtInfo *NewCapturedStmtInfo)
334         : CGF(CGF), PrevCapturedStmtInfo(CGF.CapturedStmtInfo) {
335       CGF.CapturedStmtInfo = NewCapturedStmtInfo;
336     }
337     ~CGCapturedStmtRAII() { CGF.CapturedStmtInfo = PrevCapturedStmtInfo; }
338   };
339 
340   /// An abstract representation of regular/ObjC call/message targets.
341   class AbstractCallee {
342     /// The function declaration of the callee.
343     const Decl *CalleeDecl;
344 
345   public:
346     AbstractCallee() : CalleeDecl(nullptr) {}
347     AbstractCallee(const FunctionDecl *FD) : CalleeDecl(FD) {}
348     AbstractCallee(const ObjCMethodDecl *OMD) : CalleeDecl(OMD) {}
349     bool hasFunctionDecl() const {
350       return dyn_cast_or_null<FunctionDecl>(CalleeDecl);
351     }
352     const Decl *getDecl() const { return CalleeDecl; }
353     unsigned getNumParams() const {
354       if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
355         return FD->getNumParams();
356       return cast<ObjCMethodDecl>(CalleeDecl)->param_size();
357     }
358     const ParmVarDecl *getParamDecl(unsigned I) const {
359       if (const auto *FD = dyn_cast<FunctionDecl>(CalleeDecl))
360         return FD->getParamDecl(I);
361       return *(cast<ObjCMethodDecl>(CalleeDecl)->param_begin() + I);
362     }
363   };
364 
365   /// Sanitizers enabled for this function.
366   SanitizerSet SanOpts;
367 
368   /// True if CodeGen currently emits code implementing sanitizer checks.
369   bool IsSanitizerScope;
370 
371   /// RAII object to set/unset CodeGenFunction::IsSanitizerScope.
372   class SanitizerScope {
373     CodeGenFunction *CGF;
374   public:
375     SanitizerScope(CodeGenFunction *CGF);
376     ~SanitizerScope();
377   };
378 
379   /// In C++, whether we are code generating a thunk.  This controls whether we
380   /// should emit cleanups.
381   bool CurFuncIsThunk;
382 
383   /// In ARC, whether we should autorelease the return value.
384   bool AutoreleaseResult;
385 
386   /// Whether we processed a Microsoft-style asm block during CodeGen. These can
387   /// potentially set the return value.
388   bool SawAsmBlock;
389 
390   const FunctionDecl *CurSEHParent = nullptr;
391 
392   /// True if the current function is an outlined SEH helper. This can be a
393   /// finally block or filter expression.
394   bool IsOutlinedSEHHelper;
395 
396   const CodeGen::CGBlockInfo *BlockInfo;
397   llvm::Value *BlockPointer;
398 
399   llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields;
400   FieldDecl *LambdaThisCaptureField;
401 
402   /// A mapping from NRVO variables to the flags used to indicate
403   /// when the NRVO has been applied to this variable.
404   llvm::DenseMap<const VarDecl *, llvm::Value *> NRVOFlags;
405 
406   EHScopeStack EHStack;
407   llvm::SmallVector<char, 256> LifetimeExtendedCleanupStack;
408   llvm::SmallVector<const JumpDest *, 2> SEHTryEpilogueStack;
409 
410   llvm::Instruction *CurrentFuncletPad = nullptr;
411 
412   class CallLifetimeEnd final : public EHScopeStack::Cleanup {
413     llvm::Value *Addr;
414     llvm::Value *Size;
415 
416   public:
417     CallLifetimeEnd(Address addr, llvm::Value *size)
418         : Addr(addr.getPointer()), Size(size) {}
419 
420     void Emit(CodeGenFunction &CGF, Flags flags) override {
421       CGF.EmitLifetimeEnd(Size, Addr);
422     }
423   };
424 
425   /// Header for data within LifetimeExtendedCleanupStack.
426   struct LifetimeExtendedCleanupHeader {
427     /// The size of the following cleanup object.
428     unsigned Size;
429     /// The kind of cleanup to push: a value from the CleanupKind enumeration.
430     CleanupKind Kind;
431 
432     size_t getSize() const { return Size; }
433     CleanupKind getKind() const { return Kind; }
434   };
435 
436   /// i32s containing the indexes of the cleanup destinations.
437   Address NormalCleanupDest;
438 
439   unsigned NextCleanupDestIndex;
440 
441   /// FirstBlockInfo - The head of a singly-linked-list of block layouts.
442   CGBlockInfo *FirstBlockInfo;
443 
444   /// EHResumeBlock - Unified block containing a call to llvm.eh.resume.
445   llvm::BasicBlock *EHResumeBlock;
446 
447   /// The exception slot.  All landing pads write the current exception pointer
448   /// into this alloca.
449   llvm::Value *ExceptionSlot;
450 
451   /// The selector slot.  Under the MandatoryCleanup model, all landing pads
452   /// write the current selector value into this alloca.
453   llvm::AllocaInst *EHSelectorSlot;
454 
455   /// A stack of exception code slots. Entering an __except block pushes a slot
456   /// on the stack and leaving pops one. The __exception_code() intrinsic loads
457   /// a value from the top of the stack.
458   SmallVector<Address, 1> SEHCodeSlotStack;
459 
460   /// Value returned by __exception_info intrinsic.
461   llvm::Value *SEHInfo = nullptr;
462 
463   /// Emits a landing pad for the current EH stack.
464   llvm::BasicBlock *EmitLandingPad();
465 
466   llvm::BasicBlock *getInvokeDestImpl();
467 
468   template <class T>
469   typename DominatingValue<T>::saved_type saveValueInCond(T value) {
470     return DominatingValue<T>::save(*this, value);
471   }
472 
473 public:
474   /// ObjCEHValueStack - Stack of Objective-C exception values, used for
475   /// rethrows.
476   SmallVector<llvm::Value*, 8> ObjCEHValueStack;
477 
478   /// A class controlling the emission of a finally block.
479   class FinallyInfo {
480     /// Where the catchall's edge through the cleanup should go.
481     JumpDest RethrowDest;
482 
483     /// A function to call to enter the catch.
484     llvm::Constant *BeginCatchFn;
485 
486     /// An i1 variable indicating whether or not the @finally is
487     /// running for an exception.
488     llvm::AllocaInst *ForEHVar;
489 
490     /// An i8* variable into which the exception pointer to rethrow
491     /// has been saved.
492     llvm::AllocaInst *SavedExnVar;
493 
494   public:
495     void enter(CodeGenFunction &CGF, const Stmt *Finally,
496                llvm::Constant *beginCatchFn, llvm::Constant *endCatchFn,
497                llvm::Constant *rethrowFn);
498     void exit(CodeGenFunction &CGF);
499   };
500 
501   /// Returns true inside SEH __try blocks.
502   bool isSEHTryScope() const { return !SEHTryEpilogueStack.empty(); }
503 
504   /// Returns true while emitting a cleanuppad.
505   bool isCleanupPadScope() const {
506     return CurrentFuncletPad && isa<llvm::CleanupPadInst>(CurrentFuncletPad);
507   }
508 
509   /// pushFullExprCleanup - Push a cleanup to be run at the end of the
510   /// current full-expression.  Safe against the possibility that
511   /// we're currently inside a conditionally-evaluated expression.
512   template <class T, class... As>
513   void pushFullExprCleanup(CleanupKind kind, As... A) {
514     // If we're not in a conditional branch, or if none of the
515     // arguments requires saving, then use the unconditional cleanup.
516     if (!isInConditionalBranch())
517       return EHStack.pushCleanup<T>(kind, A...);
518 
519     // Stash values in a tuple so we can guarantee the order of saves.
520     typedef std::tuple<typename DominatingValue<As>::saved_type...> SavedTuple;
521     SavedTuple Saved{saveValueInCond(A)...};
522 
523     typedef EHScopeStack::ConditionalCleanup<T, As...> CleanupType;
524     EHStack.pushCleanupTuple<CleanupType>(kind, Saved);
525     initFullExprCleanup();
526   }
527 
528   /// Queue a cleanup to be pushed after finishing the current
529   /// full-expression.
530   template <class T, class... As>
531   void pushCleanupAfterFullExpr(CleanupKind Kind, As... A) {
532     assert(!isInConditionalBranch() && "can't defer conditional cleanup");
533 
534     LifetimeExtendedCleanupHeader Header = { sizeof(T), Kind };
535 
536     size_t OldSize = LifetimeExtendedCleanupStack.size();
537     LifetimeExtendedCleanupStack.resize(
538         LifetimeExtendedCleanupStack.size() + sizeof(Header) + Header.Size);
539 
540     static_assert(sizeof(Header) % alignof(T) == 0,
541                   "Cleanup will be allocated on misaligned address");
542     char *Buffer = &LifetimeExtendedCleanupStack[OldSize];
543     new (Buffer) LifetimeExtendedCleanupHeader(Header);
544     new (Buffer + sizeof(Header)) T(A...);
545   }
546 
547   /// Set up the last cleaup that was pushed as a conditional
548   /// full-expression cleanup.
549   void initFullExprCleanup();
550 
551   /// PushDestructorCleanup - Push a cleanup to call the
552   /// complete-object destructor of an object of the given type at the
553   /// given address.  Does nothing if T is not a C++ class type with a
554   /// non-trivial destructor.
555   void PushDestructorCleanup(QualType T, Address Addr);
556 
557   /// PushDestructorCleanup - Push a cleanup to call the
558   /// complete-object variant of the given destructor on the object at
559   /// the given address.
560   void PushDestructorCleanup(const CXXDestructorDecl *Dtor, Address Addr);
561 
562   /// PopCleanupBlock - Will pop the cleanup entry on the stack and
563   /// process all branch fixups.
564   void PopCleanupBlock(bool FallThroughIsBranchThrough = false);
565 
566   /// DeactivateCleanupBlock - Deactivates the given cleanup block.
567   /// The block cannot be reactivated.  Pops it if it's the top of the
568   /// stack.
569   ///
570   /// \param DominatingIP - An instruction which is known to
571   ///   dominate the current IP (if set) and which lies along
572   ///   all paths of execution between the current IP and the
573   ///   the point at which the cleanup comes into scope.
574   void DeactivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
575                               llvm::Instruction *DominatingIP);
576 
577   /// ActivateCleanupBlock - Activates an initially-inactive cleanup.
578   /// Cannot be used to resurrect a deactivated cleanup.
579   ///
580   /// \param DominatingIP - An instruction which is known to
581   ///   dominate the current IP (if set) and which lies along
582   ///   all paths of execution between the current IP and the
583   ///   the point at which the cleanup comes into scope.
584   void ActivateCleanupBlock(EHScopeStack::stable_iterator Cleanup,
585                             llvm::Instruction *DominatingIP);
586 
587   /// Enters a new scope for capturing cleanups, all of which
588   /// will be executed once the scope is exited.
589   class RunCleanupsScope {
590     EHScopeStack::stable_iterator CleanupStackDepth, OldCleanupScopeDepth;
591     size_t LifetimeExtendedCleanupStackSize;
592     bool OldDidCallStackSave;
593   protected:
594     bool PerformCleanup;
595   private:
596 
597     RunCleanupsScope(const RunCleanupsScope &) = delete;
598     void operator=(const RunCleanupsScope &) = delete;
599 
600   protected:
601     CodeGenFunction& CGF;
602 
603   public:
604     /// Enter a new cleanup scope.
605     explicit RunCleanupsScope(CodeGenFunction &CGF)
606       : PerformCleanup(true), CGF(CGF)
607     {
608       CleanupStackDepth = CGF.EHStack.stable_begin();
609       LifetimeExtendedCleanupStackSize =
610           CGF.LifetimeExtendedCleanupStack.size();
611       OldDidCallStackSave = CGF.DidCallStackSave;
612       CGF.DidCallStackSave = false;
613       OldCleanupScopeDepth = CGF.CurrentCleanupScopeDepth;
614       CGF.CurrentCleanupScopeDepth = CleanupStackDepth;
615     }
616 
617     /// Exit this cleanup scope, emitting any accumulated cleanups.
618     ~RunCleanupsScope() {
619       if (PerformCleanup)
620         ForceCleanup();
621     }
622 
623     /// Determine whether this scope requires any cleanups.
624     bool requiresCleanups() const {
625       return CGF.EHStack.stable_begin() != CleanupStackDepth;
626     }
627 
628     /// Force the emission of cleanups now, instead of waiting
629     /// until this object is destroyed.
630     /// \param ValuesToReload - A list of values that need to be available at
631     /// the insertion point after cleanup emission. If cleanup emission created
632     /// a shared cleanup block, these value pointers will be rewritten.
633     /// Otherwise, they not will be modified.
634     void ForceCleanup(std::initializer_list<llvm::Value**> ValuesToReload = {}) {
635       assert(PerformCleanup && "Already forced cleanup");
636       CGF.DidCallStackSave = OldDidCallStackSave;
637       CGF.PopCleanupBlocks(CleanupStackDepth, LifetimeExtendedCleanupStackSize,
638                            ValuesToReload);
639       PerformCleanup = false;
640       CGF.CurrentCleanupScopeDepth = OldCleanupScopeDepth;
641     }
642   };
643 
644   // Cleanup stack depth of the RunCleanupsScope that was pushed most recently.
645   EHScopeStack::stable_iterator CurrentCleanupScopeDepth =
646       EHScopeStack::stable_end();
647 
648   class LexicalScope : public RunCleanupsScope {
649     SourceRange Range;
650     SmallVector<const LabelDecl*, 4> Labels;
651     LexicalScope *ParentScope;
652 
653     LexicalScope(const LexicalScope &) = delete;
654     void operator=(const LexicalScope &) = delete;
655 
656   public:
657     /// Enter a new cleanup scope.
658     explicit LexicalScope(CodeGenFunction &CGF, SourceRange Range)
659       : RunCleanupsScope(CGF), Range(Range), ParentScope(CGF.CurLexicalScope) {
660       CGF.CurLexicalScope = this;
661       if (CGDebugInfo *DI = CGF.getDebugInfo())
662         DI->EmitLexicalBlockStart(CGF.Builder, Range.getBegin());
663     }
664 
665     void addLabel(const LabelDecl *label) {
666       assert(PerformCleanup && "adding label to dead scope?");
667       Labels.push_back(label);
668     }
669 
670     /// Exit this cleanup scope, emitting any accumulated
671     /// cleanups.
672     ~LexicalScope() {
673       if (CGDebugInfo *DI = CGF.getDebugInfo())
674         DI->EmitLexicalBlockEnd(CGF.Builder, Range.getEnd());
675 
676       // If we should perform a cleanup, force them now.  Note that
677       // this ends the cleanup scope before rescoping any labels.
678       if (PerformCleanup) {
679         ApplyDebugLocation DL(CGF, Range.getEnd());
680         ForceCleanup();
681       }
682     }
683 
684     /// Force the emission of cleanups now, instead of waiting
685     /// until this object is destroyed.
686     void ForceCleanup() {
687       CGF.CurLexicalScope = ParentScope;
688       RunCleanupsScope::ForceCleanup();
689 
690       if (!Labels.empty())
691         rescopeLabels();
692     }
693 
694     bool hasLabels() const {
695       return !Labels.empty();
696     }
697 
698     void rescopeLabels();
699   };
700 
701   typedef llvm::DenseMap<const Decl *, Address> DeclMapTy;
702 
703   /// The class used to assign some variables some temporarily addresses.
704   class OMPMapVars {
705     DeclMapTy SavedLocals;
706     DeclMapTy SavedTempAddresses;
707     OMPMapVars(const OMPMapVars &) = delete;
708     void operator=(const OMPMapVars &) = delete;
709 
710   public:
711     explicit OMPMapVars() = default;
712     ~OMPMapVars() {
713       assert(SavedLocals.empty() && "Did not restored original addresses.");
714     };
715 
716     /// Sets the address of the variable \p LocalVD to be \p TempAddr in
717     /// function \p CGF.
718     /// \return true if at least one variable was set already, false otherwise.
719     bool setVarAddr(CodeGenFunction &CGF, const VarDecl *LocalVD,
720                     Address TempAddr) {
721       LocalVD = LocalVD->getCanonicalDecl();
722       // Only save it once.
723       if (SavedLocals.count(LocalVD)) return false;
724 
725       // Copy the existing local entry to SavedLocals.
726       auto it = CGF.LocalDeclMap.find(LocalVD);
727       if (it != CGF.LocalDeclMap.end())
728         SavedLocals.try_emplace(LocalVD, it->second);
729       else
730         SavedLocals.try_emplace(LocalVD, Address::invalid());
731 
732       // Generate the private entry.
733       QualType VarTy = LocalVD->getType();
734       if (VarTy->isReferenceType()) {
735         Address Temp = CGF.CreateMemTemp(VarTy);
736         CGF.Builder.CreateStore(TempAddr.getPointer(), Temp);
737         TempAddr = Temp;
738       }
739       SavedTempAddresses.try_emplace(LocalVD, TempAddr);
740 
741       return true;
742     }
743 
744     /// Applies new addresses to the list of the variables.
745     /// \return true if at least one variable is using new address, false
746     /// otherwise.
747     bool apply(CodeGenFunction &CGF) {
748       copyInto(SavedTempAddresses, CGF.LocalDeclMap);
749       SavedTempAddresses.clear();
750       return !SavedLocals.empty();
751     }
752 
753     /// Restores original addresses of the variables.
754     void restore(CodeGenFunction &CGF) {
755       if (!SavedLocals.empty()) {
756         copyInto(SavedLocals, CGF.LocalDeclMap);
757         SavedLocals.clear();
758       }
759     }
760 
761   private:
762     /// Copy all the entries in the source map over the corresponding
763     /// entries in the destination, which must exist.
764     static void copyInto(const DeclMapTy &Src, DeclMapTy &Dest) {
765       for (auto &Pair : Src) {
766         if (!Pair.second.isValid()) {
767           Dest.erase(Pair.first);
768           continue;
769         }
770 
771         auto I = Dest.find(Pair.first);
772         if (I != Dest.end())
773           I->second = Pair.second;
774         else
775           Dest.insert(Pair);
776       }
777     }
778   };
779 
780   /// The scope used to remap some variables as private in the OpenMP loop body
781   /// (or other captured region emitted without outlining), and to restore old
782   /// vars back on exit.
783   class OMPPrivateScope : public RunCleanupsScope {
784     OMPMapVars MappedVars;
785     OMPPrivateScope(const OMPPrivateScope &) = delete;
786     void operator=(const OMPPrivateScope &) = delete;
787 
788   public:
789     /// Enter a new OpenMP private scope.
790     explicit OMPPrivateScope(CodeGenFunction &CGF) : RunCleanupsScope(CGF) {}
791 
792     /// Registers \p LocalVD variable as a private and apply \p PrivateGen
793     /// function for it to generate corresponding private variable. \p
794     /// PrivateGen returns an address of the generated private variable.
795     /// \return true if the variable is registered as private, false if it has
796     /// been privatized already.
797     bool addPrivate(const VarDecl *LocalVD,
798                     const llvm::function_ref<Address()> PrivateGen) {
799       assert(PerformCleanup && "adding private to dead scope");
800       return MappedVars.setVarAddr(CGF, LocalVD, PrivateGen());
801     }
802 
803     /// Privatizes local variables previously registered as private.
804     /// Registration is separate from the actual privatization to allow
805     /// initializers use values of the original variables, not the private one.
806     /// This is important, for example, if the private variable is a class
807     /// variable initialized by a constructor that references other private
808     /// variables. But at initialization original variables must be used, not
809     /// private copies.
810     /// \return true if at least one variable was privatized, false otherwise.
811     bool Privatize() { return MappedVars.apply(CGF); }
812 
813     void ForceCleanup() {
814       RunCleanupsScope::ForceCleanup();
815       MappedVars.restore(CGF);
816     }
817 
818     /// Exit scope - all the mapped variables are restored.
819     ~OMPPrivateScope() {
820       if (PerformCleanup)
821         ForceCleanup();
822     }
823 
824     /// Checks if the global variable is captured in current function.
825     bool isGlobalVarCaptured(const VarDecl *VD) const {
826       VD = VD->getCanonicalDecl();
827       return !VD->isLocalVarDeclOrParm() && CGF.LocalDeclMap.count(VD) > 0;
828     }
829   };
830 
831   /// Takes the old cleanup stack size and emits the cleanup blocks
832   /// that have been added.
833   void
834   PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
835                    std::initializer_list<llvm::Value **> ValuesToReload = {});
836 
837   /// Takes the old cleanup stack size and emits the cleanup blocks
838   /// that have been added, then adds all lifetime-extended cleanups from
839   /// the given position to the stack.
840   void
841   PopCleanupBlocks(EHScopeStack::stable_iterator OldCleanupStackSize,
842                    size_t OldLifetimeExtendedStackSize,
843                    std::initializer_list<llvm::Value **> ValuesToReload = {});
844 
845   void ResolveBranchFixups(llvm::BasicBlock *Target);
846 
847   /// The given basic block lies in the current EH scope, but may be a
848   /// target of a potentially scope-crossing jump; get a stable handle
849   /// to which we can perform this jump later.
850   JumpDest getJumpDestInCurrentScope(llvm::BasicBlock *Target) {
851     return JumpDest(Target,
852                     EHStack.getInnermostNormalCleanup(),
853                     NextCleanupDestIndex++);
854   }
855 
856   /// The given basic block lies in the current EH scope, but may be a
857   /// target of a potentially scope-crossing jump; get a stable handle
858   /// to which we can perform this jump later.
859   JumpDest getJumpDestInCurrentScope(StringRef Name = StringRef()) {
860     return getJumpDestInCurrentScope(createBasicBlock(Name));
861   }
862 
863   /// EmitBranchThroughCleanup - Emit a branch from the current insert
864   /// block through the normal cleanup handling code (if any) and then
865   /// on to \arg Dest.
866   void EmitBranchThroughCleanup(JumpDest Dest);
867 
868   /// isObviouslyBranchWithoutCleanups - Return true if a branch to the
869   /// specified destination obviously has no cleanups to run.  'false' is always
870   /// a conservatively correct answer for this method.
871   bool isObviouslyBranchWithoutCleanups(JumpDest Dest) const;
872 
873   /// popCatchScope - Pops the catch scope at the top of the EHScope
874   /// stack, emitting any required code (other than the catch handlers
875   /// themselves).
876   void popCatchScope();
877 
878   llvm::BasicBlock *getEHResumeBlock(bool isCleanup);
879   llvm::BasicBlock *getEHDispatchBlock(EHScopeStack::stable_iterator scope);
880   llvm::BasicBlock *
881   getFuncletEHDispatchBlock(EHScopeStack::stable_iterator scope);
882 
883   /// An object to manage conditionally-evaluated expressions.
884   class ConditionalEvaluation {
885     llvm::BasicBlock *StartBB;
886 
887   public:
888     ConditionalEvaluation(CodeGenFunction &CGF)
889       : StartBB(CGF.Builder.GetInsertBlock()) {}
890 
891     void begin(CodeGenFunction &CGF) {
892       assert(CGF.OutermostConditional != this);
893       if (!CGF.OutermostConditional)
894         CGF.OutermostConditional = this;
895     }
896 
897     void end(CodeGenFunction &CGF) {
898       assert(CGF.OutermostConditional != nullptr);
899       if (CGF.OutermostConditional == this)
900         CGF.OutermostConditional = nullptr;
901     }
902 
903     /// Returns a block which will be executed prior to each
904     /// evaluation of the conditional code.
905     llvm::BasicBlock *getStartingBlock() const {
906       return StartBB;
907     }
908   };
909 
910   /// isInConditionalBranch - Return true if we're currently emitting
911   /// one branch or the other of a conditional expression.
912   bool isInConditionalBranch() const { return OutermostConditional != nullptr; }
913 
914   void setBeforeOutermostConditional(llvm::Value *value, Address addr) {
915     assert(isInConditionalBranch());
916     llvm::BasicBlock *block = OutermostConditional->getStartingBlock();
917     auto store = new llvm::StoreInst(value, addr.getPointer(), &block->back());
918     store->setAlignment(addr.getAlignment().getQuantity());
919   }
920 
921   /// An RAII object to record that we're evaluating a statement
922   /// expression.
923   class StmtExprEvaluation {
924     CodeGenFunction &CGF;
925 
926     /// We have to save the outermost conditional: cleanups in a
927     /// statement expression aren't conditional just because the
928     /// StmtExpr is.
929     ConditionalEvaluation *SavedOutermostConditional;
930 
931   public:
932     StmtExprEvaluation(CodeGenFunction &CGF)
933       : CGF(CGF), SavedOutermostConditional(CGF.OutermostConditional) {
934       CGF.OutermostConditional = nullptr;
935     }
936 
937     ~StmtExprEvaluation() {
938       CGF.OutermostConditional = SavedOutermostConditional;
939       CGF.EnsureInsertPoint();
940     }
941   };
942 
943   /// An object which temporarily prevents a value from being
944   /// destroyed by aggressive peephole optimizations that assume that
945   /// all uses of a value have been realized in the IR.
946   class PeepholeProtection {
947     llvm::Instruction *Inst;
948     friend class CodeGenFunction;
949 
950   public:
951     PeepholeProtection() : Inst(nullptr) {}
952   };
953 
954   /// A non-RAII class containing all the information about a bound
955   /// opaque value.  OpaqueValueMapping, below, is a RAII wrapper for
956   /// this which makes individual mappings very simple; using this
957   /// class directly is useful when you have a variable number of
958   /// opaque values or don't want the RAII functionality for some
959   /// reason.
960   class OpaqueValueMappingData {
961     const OpaqueValueExpr *OpaqueValue;
962     bool BoundLValue;
963     CodeGenFunction::PeepholeProtection Protection;
964 
965     OpaqueValueMappingData(const OpaqueValueExpr *ov,
966                            bool boundLValue)
967       : OpaqueValue(ov), BoundLValue(boundLValue) {}
968   public:
969     OpaqueValueMappingData() : OpaqueValue(nullptr) {}
970 
971     static bool shouldBindAsLValue(const Expr *expr) {
972       // gl-values should be bound as l-values for obvious reasons.
973       // Records should be bound as l-values because IR generation
974       // always keeps them in memory.  Expressions of function type
975       // act exactly like l-values but are formally required to be
976       // r-values in C.
977       return expr->isGLValue() ||
978              expr->getType()->isFunctionType() ||
979              hasAggregateEvaluationKind(expr->getType());
980     }
981 
982     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
983                                        const OpaqueValueExpr *ov,
984                                        const Expr *e) {
985       if (shouldBindAsLValue(ov))
986         return bind(CGF, ov, CGF.EmitLValue(e));
987       return bind(CGF, ov, CGF.EmitAnyExpr(e));
988     }
989 
990     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
991                                        const OpaqueValueExpr *ov,
992                                        const LValue &lv) {
993       assert(shouldBindAsLValue(ov));
994       CGF.OpaqueLValues.insert(std::make_pair(ov, lv));
995       return OpaqueValueMappingData(ov, true);
996     }
997 
998     static OpaqueValueMappingData bind(CodeGenFunction &CGF,
999                                        const OpaqueValueExpr *ov,
1000                                        const RValue &rv) {
1001       assert(!shouldBindAsLValue(ov));
1002       CGF.OpaqueRValues.insert(std::make_pair(ov, rv));
1003 
1004       OpaqueValueMappingData data(ov, false);
1005 
1006       // Work around an extremely aggressive peephole optimization in
1007       // EmitScalarConversion which assumes that all other uses of a
1008       // value are extant.
1009       data.Protection = CGF.protectFromPeepholes(rv);
1010 
1011       return data;
1012     }
1013 
1014     bool isValid() const { return OpaqueValue != nullptr; }
1015     void clear() { OpaqueValue = nullptr; }
1016 
1017     void unbind(CodeGenFunction &CGF) {
1018       assert(OpaqueValue && "no data to unbind!");
1019 
1020       if (BoundLValue) {
1021         CGF.OpaqueLValues.erase(OpaqueValue);
1022       } else {
1023         CGF.OpaqueRValues.erase(OpaqueValue);
1024         CGF.unprotectFromPeepholes(Protection);
1025       }
1026     }
1027   };
1028 
1029   /// An RAII object to set (and then clear) a mapping for an OpaqueValueExpr.
1030   class OpaqueValueMapping {
1031     CodeGenFunction &CGF;
1032     OpaqueValueMappingData Data;
1033 
1034   public:
1035     static bool shouldBindAsLValue(const Expr *expr) {
1036       return OpaqueValueMappingData::shouldBindAsLValue(expr);
1037     }
1038 
1039     /// Build the opaque value mapping for the given conditional
1040     /// operator if it's the GNU ?: extension.  This is a common
1041     /// enough pattern that the convenience operator is really
1042     /// helpful.
1043     ///
1044     OpaqueValueMapping(CodeGenFunction &CGF,
1045                        const AbstractConditionalOperator *op) : CGF(CGF) {
1046       if (isa<ConditionalOperator>(op))
1047         // Leave Data empty.
1048         return;
1049 
1050       const BinaryConditionalOperator *e = cast<BinaryConditionalOperator>(op);
1051       Data = OpaqueValueMappingData::bind(CGF, e->getOpaqueValue(),
1052                                           e->getCommon());
1053     }
1054 
1055     /// Build the opaque value mapping for an OpaqueValueExpr whose source
1056     /// expression is set to the expression the OVE represents.
1057     OpaqueValueMapping(CodeGenFunction &CGF, const OpaqueValueExpr *OV)
1058         : CGF(CGF) {
1059       if (OV) {
1060         assert(OV->getSourceExpr() && "wrong form of OpaqueValueMapping used "
1061                                       "for OVE with no source expression");
1062         Data = OpaqueValueMappingData::bind(CGF, OV, OV->getSourceExpr());
1063       }
1064     }
1065 
1066     OpaqueValueMapping(CodeGenFunction &CGF,
1067                        const OpaqueValueExpr *opaqueValue,
1068                        LValue lvalue)
1069       : CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, lvalue)) {
1070     }
1071 
1072     OpaqueValueMapping(CodeGenFunction &CGF,
1073                        const OpaqueValueExpr *opaqueValue,
1074                        RValue rvalue)
1075       : CGF(CGF), Data(OpaqueValueMappingData::bind(CGF, opaqueValue, rvalue)) {
1076     }
1077 
1078     void pop() {
1079       Data.unbind(CGF);
1080       Data.clear();
1081     }
1082 
1083     ~OpaqueValueMapping() {
1084       if (Data.isValid()) Data.unbind(CGF);
1085     }
1086   };
1087 
1088 private:
1089   CGDebugInfo *DebugInfo;
1090   bool DisableDebugInfo;
1091 
1092   /// DidCallStackSave - Whether llvm.stacksave has been called. Used to avoid
1093   /// calling llvm.stacksave for multiple VLAs in the same scope.
1094   bool DidCallStackSave;
1095 
1096   /// IndirectBranch - The first time an indirect goto is seen we create a block
1097   /// with an indirect branch.  Every time we see the address of a label taken,
1098   /// we add the label to the indirect goto.  Every subsequent indirect goto is
1099   /// codegen'd as a jump to the IndirectBranch's basic block.
1100   llvm::IndirectBrInst *IndirectBranch;
1101 
1102   /// LocalDeclMap - This keeps track of the LLVM allocas or globals for local C
1103   /// decls.
1104   DeclMapTy LocalDeclMap;
1105 
1106   // Keep track of the cleanups for callee-destructed parameters pushed to the
1107   // cleanup stack so that they can be deactivated later.
1108   llvm::DenseMap<const ParmVarDecl *, EHScopeStack::stable_iterator>
1109       CalleeDestructedParamCleanups;
1110 
1111   /// SizeArguments - If a ParmVarDecl had the pass_object_size attribute, this
1112   /// will contain a mapping from said ParmVarDecl to its implicit "object_size"
1113   /// parameter.
1114   llvm::SmallDenseMap<const ParmVarDecl *, const ImplicitParamDecl *, 2>
1115       SizeArguments;
1116 
1117   /// Track escaped local variables with auto storage. Used during SEH
1118   /// outlining to produce a call to llvm.localescape.
1119   llvm::DenseMap<llvm::AllocaInst *, int> EscapedLocals;
1120 
1121   /// LabelMap - This keeps track of the LLVM basic block for each C label.
1122   llvm::DenseMap<const LabelDecl*, JumpDest> LabelMap;
1123 
1124   // BreakContinueStack - This keeps track of where break and continue
1125   // statements should jump to.
1126   struct BreakContinue {
1127     BreakContinue(JumpDest Break, JumpDest Continue)
1128       : BreakBlock(Break), ContinueBlock(Continue) {}
1129 
1130     JumpDest BreakBlock;
1131     JumpDest ContinueBlock;
1132   };
1133   SmallVector<BreakContinue, 8> BreakContinueStack;
1134 
1135   /// Handles cancellation exit points in OpenMP-related constructs.
1136   class OpenMPCancelExitStack {
1137     /// Tracks cancellation exit point and join point for cancel-related exit
1138     /// and normal exit.
1139     struct CancelExit {
1140       CancelExit() = default;
1141       CancelExit(OpenMPDirectiveKind Kind, JumpDest ExitBlock,
1142                  JumpDest ContBlock)
1143           : Kind(Kind), ExitBlock(ExitBlock), ContBlock(ContBlock) {}
1144       OpenMPDirectiveKind Kind = OMPD_unknown;
1145       /// true if the exit block has been emitted already by the special
1146       /// emitExit() call, false if the default codegen is used.
1147       bool HasBeenEmitted = false;
1148       JumpDest ExitBlock;
1149       JumpDest ContBlock;
1150     };
1151 
1152     SmallVector<CancelExit, 8> Stack;
1153 
1154   public:
1155     OpenMPCancelExitStack() : Stack(1) {}
1156     ~OpenMPCancelExitStack() = default;
1157     /// Fetches the exit block for the current OpenMP construct.
1158     JumpDest getExitBlock() const { return Stack.back().ExitBlock; }
1159     /// Emits exit block with special codegen procedure specific for the related
1160     /// OpenMP construct + emits code for normal construct cleanup.
1161     void emitExit(CodeGenFunction &CGF, OpenMPDirectiveKind Kind,
1162                   const llvm::function_ref<void(CodeGenFunction &)> CodeGen) {
1163       if (Stack.back().Kind == Kind && getExitBlock().isValid()) {
1164         assert(CGF.getOMPCancelDestination(Kind).isValid());
1165         assert(CGF.HaveInsertPoint());
1166         assert(!Stack.back().HasBeenEmitted);
1167         auto IP = CGF.Builder.saveAndClearIP();
1168         CGF.EmitBlock(Stack.back().ExitBlock.getBlock());
1169         CodeGen(CGF);
1170         CGF.EmitBranch(Stack.back().ContBlock.getBlock());
1171         CGF.Builder.restoreIP(IP);
1172         Stack.back().HasBeenEmitted = true;
1173       }
1174       CodeGen(CGF);
1175     }
1176     /// Enter the cancel supporting \a Kind construct.
1177     /// \param Kind OpenMP directive that supports cancel constructs.
1178     /// \param HasCancel true, if the construct has inner cancel directive,
1179     /// false otherwise.
1180     void enter(CodeGenFunction &CGF, OpenMPDirectiveKind Kind, bool HasCancel) {
1181       Stack.push_back({Kind,
1182                        HasCancel ? CGF.getJumpDestInCurrentScope("cancel.exit")
1183                                  : JumpDest(),
1184                        HasCancel ? CGF.getJumpDestInCurrentScope("cancel.cont")
1185                                  : JumpDest()});
1186     }
1187     /// Emits default exit point for the cancel construct (if the special one
1188     /// has not be used) + join point for cancel/normal exits.
1189     void exit(CodeGenFunction &CGF) {
1190       if (getExitBlock().isValid()) {
1191         assert(CGF.getOMPCancelDestination(Stack.back().Kind).isValid());
1192         bool HaveIP = CGF.HaveInsertPoint();
1193         if (!Stack.back().HasBeenEmitted) {
1194           if (HaveIP)
1195             CGF.EmitBranchThroughCleanup(Stack.back().ContBlock);
1196           CGF.EmitBlock(Stack.back().ExitBlock.getBlock());
1197           CGF.EmitBranchThroughCleanup(Stack.back().ContBlock);
1198         }
1199         CGF.EmitBlock(Stack.back().ContBlock.getBlock());
1200         if (!HaveIP) {
1201           CGF.Builder.CreateUnreachable();
1202           CGF.Builder.ClearInsertionPoint();
1203         }
1204       }
1205       Stack.pop_back();
1206     }
1207   };
1208   OpenMPCancelExitStack OMPCancelStack;
1209 
1210   CodeGenPGO PGO;
1211 
1212   /// Calculate branch weights appropriate for PGO data
1213   llvm::MDNode *createProfileWeights(uint64_t TrueCount, uint64_t FalseCount);
1214   llvm::MDNode *createProfileWeights(ArrayRef<uint64_t> Weights);
1215   llvm::MDNode *createProfileWeightsForLoop(const Stmt *Cond,
1216                                             uint64_t LoopCount);
1217 
1218 public:
1219   /// Increment the profiler's counter for the given statement by \p StepV.
1220   /// If \p StepV is null, the default increment is 1.
1221   void incrementProfileCounter(const Stmt *S, llvm::Value *StepV = nullptr) {
1222     if (CGM.getCodeGenOpts().hasProfileClangInstr())
1223       PGO.emitCounterIncrement(Builder, S, StepV);
1224     PGO.setCurrentStmt(S);
1225   }
1226 
1227   /// Get the profiler's count for the given statement.
1228   uint64_t getProfileCount(const Stmt *S) {
1229     Optional<uint64_t> Count = PGO.getStmtCount(S);
1230     if (!Count.hasValue())
1231       return 0;
1232     return *Count;
1233   }
1234 
1235   /// Set the profiler's current count.
1236   void setCurrentProfileCount(uint64_t Count) {
1237     PGO.setCurrentRegionCount(Count);
1238   }
1239 
1240   /// Get the profiler's current count. This is generally the count for the most
1241   /// recently incremented counter.
1242   uint64_t getCurrentProfileCount() {
1243     return PGO.getCurrentRegionCount();
1244   }
1245 
1246 private:
1247 
1248   /// SwitchInsn - This is nearest current switch instruction. It is null if
1249   /// current context is not in a switch.
1250   llvm::SwitchInst *SwitchInsn;
1251   /// The branch weights of SwitchInsn when doing instrumentation based PGO.
1252   SmallVector<uint64_t, 16> *SwitchWeights;
1253 
1254   /// CaseRangeBlock - This block holds if condition check for last case
1255   /// statement range in current switch instruction.
1256   llvm::BasicBlock *CaseRangeBlock;
1257 
1258   /// OpaqueLValues - Keeps track of the current set of opaque value
1259   /// expressions.
1260   llvm::DenseMap<const OpaqueValueExpr *, LValue> OpaqueLValues;
1261   llvm::DenseMap<const OpaqueValueExpr *, RValue> OpaqueRValues;
1262 
1263   // VLASizeMap - This keeps track of the associated size for each VLA type.
1264   // We track this by the size expression rather than the type itself because
1265   // in certain situations, like a const qualifier applied to an VLA typedef,
1266   // multiple VLA types can share the same size expression.
1267   // FIXME: Maybe this could be a stack of maps that is pushed/popped as we
1268   // enter/leave scopes.
1269   llvm::DenseMap<const Expr*, llvm::Value*> VLASizeMap;
1270 
1271   /// A block containing a single 'unreachable' instruction.  Created
1272   /// lazily by getUnreachableBlock().
1273   llvm::BasicBlock *UnreachableBlock;
1274 
1275   /// Counts of the number return expressions in the function.
1276   unsigned NumReturnExprs;
1277 
1278   /// Count the number of simple (constant) return expressions in the function.
1279   unsigned NumSimpleReturnExprs;
1280 
1281   /// The last regular (non-return) debug location (breakpoint) in the function.
1282   SourceLocation LastStopPoint;
1283 
1284 public:
1285   /// A scope within which we are constructing the fields of an object which
1286   /// might use a CXXDefaultInitExpr. This stashes away a 'this' value to use
1287   /// if we need to evaluate a CXXDefaultInitExpr within the evaluation.
1288   class FieldConstructionScope {
1289   public:
1290     FieldConstructionScope(CodeGenFunction &CGF, Address This)
1291         : CGF(CGF), OldCXXDefaultInitExprThis(CGF.CXXDefaultInitExprThis) {
1292       CGF.CXXDefaultInitExprThis = This;
1293     }
1294     ~FieldConstructionScope() {
1295       CGF.CXXDefaultInitExprThis = OldCXXDefaultInitExprThis;
1296     }
1297 
1298   private:
1299     CodeGenFunction &CGF;
1300     Address OldCXXDefaultInitExprThis;
1301   };
1302 
1303   /// The scope of a CXXDefaultInitExpr. Within this scope, the value of 'this'
1304   /// is overridden to be the object under construction.
1305   class CXXDefaultInitExprScope {
1306   public:
1307     CXXDefaultInitExprScope(CodeGenFunction &CGF)
1308       : CGF(CGF), OldCXXThisValue(CGF.CXXThisValue),
1309         OldCXXThisAlignment(CGF.CXXThisAlignment) {
1310       CGF.CXXThisValue = CGF.CXXDefaultInitExprThis.getPointer();
1311       CGF.CXXThisAlignment = CGF.CXXDefaultInitExprThis.getAlignment();
1312     }
1313     ~CXXDefaultInitExprScope() {
1314       CGF.CXXThisValue = OldCXXThisValue;
1315       CGF.CXXThisAlignment = OldCXXThisAlignment;
1316     }
1317 
1318   public:
1319     CodeGenFunction &CGF;
1320     llvm::Value *OldCXXThisValue;
1321     CharUnits OldCXXThisAlignment;
1322   };
1323 
1324   /// The scope of an ArrayInitLoopExpr. Within this scope, the value of the
1325   /// current loop index is overridden.
1326   class ArrayInitLoopExprScope {
1327   public:
1328     ArrayInitLoopExprScope(CodeGenFunction &CGF, llvm::Value *Index)
1329       : CGF(CGF), OldArrayInitIndex(CGF.ArrayInitIndex) {
1330       CGF.ArrayInitIndex = Index;
1331     }
1332     ~ArrayInitLoopExprScope() {
1333       CGF.ArrayInitIndex = OldArrayInitIndex;
1334     }
1335 
1336   private:
1337     CodeGenFunction &CGF;
1338     llvm::Value *OldArrayInitIndex;
1339   };
1340 
1341   class InlinedInheritingConstructorScope {
1342   public:
1343     InlinedInheritingConstructorScope(CodeGenFunction &CGF, GlobalDecl GD)
1344         : CGF(CGF), OldCurGD(CGF.CurGD), OldCurFuncDecl(CGF.CurFuncDecl),
1345           OldCurCodeDecl(CGF.CurCodeDecl),
1346           OldCXXABIThisDecl(CGF.CXXABIThisDecl),
1347           OldCXXABIThisValue(CGF.CXXABIThisValue),
1348           OldCXXThisValue(CGF.CXXThisValue),
1349           OldCXXABIThisAlignment(CGF.CXXABIThisAlignment),
1350           OldCXXThisAlignment(CGF.CXXThisAlignment),
1351           OldReturnValue(CGF.ReturnValue), OldFnRetTy(CGF.FnRetTy),
1352           OldCXXInheritedCtorInitExprArgs(
1353               std::move(CGF.CXXInheritedCtorInitExprArgs)) {
1354       CGF.CurGD = GD;
1355       CGF.CurFuncDecl = CGF.CurCodeDecl =
1356           cast<CXXConstructorDecl>(GD.getDecl());
1357       CGF.CXXABIThisDecl = nullptr;
1358       CGF.CXXABIThisValue = nullptr;
1359       CGF.CXXThisValue = nullptr;
1360       CGF.CXXABIThisAlignment = CharUnits();
1361       CGF.CXXThisAlignment = CharUnits();
1362       CGF.ReturnValue = Address::invalid();
1363       CGF.FnRetTy = QualType();
1364       CGF.CXXInheritedCtorInitExprArgs.clear();
1365     }
1366     ~InlinedInheritingConstructorScope() {
1367       CGF.CurGD = OldCurGD;
1368       CGF.CurFuncDecl = OldCurFuncDecl;
1369       CGF.CurCodeDecl = OldCurCodeDecl;
1370       CGF.CXXABIThisDecl = OldCXXABIThisDecl;
1371       CGF.CXXABIThisValue = OldCXXABIThisValue;
1372       CGF.CXXThisValue = OldCXXThisValue;
1373       CGF.CXXABIThisAlignment = OldCXXABIThisAlignment;
1374       CGF.CXXThisAlignment = OldCXXThisAlignment;
1375       CGF.ReturnValue = OldReturnValue;
1376       CGF.FnRetTy = OldFnRetTy;
1377       CGF.CXXInheritedCtorInitExprArgs =
1378           std::move(OldCXXInheritedCtorInitExprArgs);
1379     }
1380 
1381   private:
1382     CodeGenFunction &CGF;
1383     GlobalDecl OldCurGD;
1384     const Decl *OldCurFuncDecl;
1385     const Decl *OldCurCodeDecl;
1386     ImplicitParamDecl *OldCXXABIThisDecl;
1387     llvm::Value *OldCXXABIThisValue;
1388     llvm::Value *OldCXXThisValue;
1389     CharUnits OldCXXABIThisAlignment;
1390     CharUnits OldCXXThisAlignment;
1391     Address OldReturnValue;
1392     QualType OldFnRetTy;
1393     CallArgList OldCXXInheritedCtorInitExprArgs;
1394   };
1395 
1396 private:
1397   /// CXXThisDecl - When generating code for a C++ member function,
1398   /// this will hold the implicit 'this' declaration.
1399   ImplicitParamDecl *CXXABIThisDecl;
1400   llvm::Value *CXXABIThisValue;
1401   llvm::Value *CXXThisValue;
1402   CharUnits CXXABIThisAlignment;
1403   CharUnits CXXThisAlignment;
1404 
1405   /// The value of 'this' to use when evaluating CXXDefaultInitExprs within
1406   /// this expression.
1407   Address CXXDefaultInitExprThis = Address::invalid();
1408 
1409   /// The current array initialization index when evaluating an
1410   /// ArrayInitIndexExpr within an ArrayInitLoopExpr.
1411   llvm::Value *ArrayInitIndex = nullptr;
1412 
1413   /// The values of function arguments to use when evaluating
1414   /// CXXInheritedCtorInitExprs within this context.
1415   CallArgList CXXInheritedCtorInitExprArgs;
1416 
1417   /// CXXStructorImplicitParamDecl - When generating code for a constructor or
1418   /// destructor, this will hold the implicit argument (e.g. VTT).
1419   ImplicitParamDecl *CXXStructorImplicitParamDecl;
1420   llvm::Value *CXXStructorImplicitParamValue;
1421 
1422   /// OutermostConditional - Points to the outermost active
1423   /// conditional control.  This is used so that we know if a
1424   /// temporary should be destroyed conditionally.
1425   ConditionalEvaluation *OutermostConditional;
1426 
1427   /// The current lexical scope.
1428   LexicalScope *CurLexicalScope;
1429 
1430   /// The current source location that should be used for exception
1431   /// handling code.
1432   SourceLocation CurEHLocation;
1433 
1434   /// BlockByrefInfos - For each __block variable, contains
1435   /// information about the layout of the variable.
1436   llvm::DenseMap<const ValueDecl *, BlockByrefInfo> BlockByrefInfos;
1437 
1438   /// Used by -fsanitize=nullability-return to determine whether the return
1439   /// value can be checked.
1440   llvm::Value *RetValNullabilityPrecondition = nullptr;
1441 
1442   /// Check if -fsanitize=nullability-return instrumentation is required for
1443   /// this function.
1444   bool requiresReturnValueNullabilityCheck() const {
1445     return RetValNullabilityPrecondition;
1446   }
1447 
1448   /// Used to store precise source locations for return statements by the
1449   /// runtime return value checks.
1450   Address ReturnLocation = Address::invalid();
1451 
1452   /// Check if the return value of this function requires sanitization.
1453   bool requiresReturnValueCheck() const {
1454     return requiresReturnValueNullabilityCheck() ||
1455            (SanOpts.has(SanitizerKind::ReturnsNonnullAttribute) &&
1456             CurCodeDecl && CurCodeDecl->getAttr<ReturnsNonNullAttr>());
1457   }
1458 
1459   llvm::BasicBlock *TerminateLandingPad;
1460   llvm::BasicBlock *TerminateHandler;
1461   llvm::BasicBlock *TrapBB;
1462 
1463   /// Terminate funclets keyed by parent funclet pad.
1464   llvm::MapVector<llvm::Value *, llvm::BasicBlock *> TerminateFunclets;
1465 
1466   /// True if we need emit the life-time markers.
1467   const bool ShouldEmitLifetimeMarkers;
1468 
1469   /// Add OpenCL kernel arg metadata and the kernel attribute metadata to
1470   /// the function metadata.
1471   void EmitOpenCLKernelMetadata(const FunctionDecl *FD,
1472                                 llvm::Function *Fn);
1473 
1474 public:
1475   CodeGenFunction(CodeGenModule &cgm, bool suppressNewContext=false);
1476   ~CodeGenFunction();
1477 
1478   CodeGenTypes &getTypes() const { return CGM.getTypes(); }
1479   ASTContext &getContext() const { return CGM.getContext(); }
1480   CGDebugInfo *getDebugInfo() {
1481     if (DisableDebugInfo)
1482       return nullptr;
1483     return DebugInfo;
1484   }
1485   void disableDebugInfo() { DisableDebugInfo = true; }
1486   void enableDebugInfo() { DisableDebugInfo = false; }
1487 
1488   bool shouldUseFusedARCCalls() {
1489     return CGM.getCodeGenOpts().OptimizationLevel == 0;
1490   }
1491 
1492   const LangOptions &getLangOpts() const { return CGM.getLangOpts(); }
1493 
1494   /// Returns a pointer to the function's exception object and selector slot,
1495   /// which is assigned in every landing pad.
1496   Address getExceptionSlot();
1497   Address getEHSelectorSlot();
1498 
1499   /// Returns the contents of the function's exception object and selector
1500   /// slots.
1501   llvm::Value *getExceptionFromSlot();
1502   llvm::Value *getSelectorFromSlot();
1503 
1504   Address getNormalCleanupDestSlot();
1505 
1506   llvm::BasicBlock *getUnreachableBlock() {
1507     if (!UnreachableBlock) {
1508       UnreachableBlock = createBasicBlock("unreachable");
1509       new llvm::UnreachableInst(getLLVMContext(), UnreachableBlock);
1510     }
1511     return UnreachableBlock;
1512   }
1513 
1514   llvm::BasicBlock *getInvokeDest() {
1515     if (!EHStack.requiresLandingPad()) return nullptr;
1516     return getInvokeDestImpl();
1517   }
1518 
1519   bool currentFunctionUsesSEHTry() const { return CurSEHParent != nullptr; }
1520 
1521   const TargetInfo &getTarget() const { return Target; }
1522   llvm::LLVMContext &getLLVMContext() { return CGM.getLLVMContext(); }
1523   const TargetCodeGenInfo &getTargetHooks() const {
1524     return CGM.getTargetCodeGenInfo();
1525   }
1526 
1527   //===--------------------------------------------------------------------===//
1528   //                                  Cleanups
1529   //===--------------------------------------------------------------------===//
1530 
1531   typedef void Destroyer(CodeGenFunction &CGF, Address addr, QualType ty);
1532 
1533   void pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
1534                                         Address arrayEndPointer,
1535                                         QualType elementType,
1536                                         CharUnits elementAlignment,
1537                                         Destroyer *destroyer);
1538   void pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
1539                                       llvm::Value *arrayEnd,
1540                                       QualType elementType,
1541                                       CharUnits elementAlignment,
1542                                       Destroyer *destroyer);
1543 
1544   void pushDestroy(QualType::DestructionKind dtorKind,
1545                    Address addr, QualType type);
1546   void pushEHDestroy(QualType::DestructionKind dtorKind,
1547                      Address addr, QualType type);
1548   void pushDestroy(CleanupKind kind, Address addr, QualType type,
1549                    Destroyer *destroyer, bool useEHCleanupForArray);
1550   void pushLifetimeExtendedDestroy(CleanupKind kind, Address addr,
1551                                    QualType type, Destroyer *destroyer,
1552                                    bool useEHCleanupForArray);
1553   void pushCallObjectDeleteCleanup(const FunctionDecl *OperatorDelete,
1554                                    llvm::Value *CompletePtr,
1555                                    QualType ElementType);
1556   void pushStackRestore(CleanupKind kind, Address SPMem);
1557   void emitDestroy(Address addr, QualType type, Destroyer *destroyer,
1558                    bool useEHCleanupForArray);
1559   llvm::Function *generateDestroyHelper(Address addr, QualType type,
1560                                         Destroyer *destroyer,
1561                                         bool useEHCleanupForArray,
1562                                         const VarDecl *VD);
1563   void emitArrayDestroy(llvm::Value *begin, llvm::Value *end,
1564                         QualType elementType, CharUnits elementAlign,
1565                         Destroyer *destroyer,
1566                         bool checkZeroLength, bool useEHCleanup);
1567 
1568   Destroyer *getDestroyer(QualType::DestructionKind destructionKind);
1569 
1570   /// Determines whether an EH cleanup is required to destroy a type
1571   /// with the given destruction kind.
1572   bool needsEHCleanup(QualType::DestructionKind kind) {
1573     switch (kind) {
1574     case QualType::DK_none:
1575       return false;
1576     case QualType::DK_cxx_destructor:
1577     case QualType::DK_objc_weak_lifetime:
1578     case QualType::DK_nontrivial_c_struct:
1579       return getLangOpts().Exceptions;
1580     case QualType::DK_objc_strong_lifetime:
1581       return getLangOpts().Exceptions &&
1582              CGM.getCodeGenOpts().ObjCAutoRefCountExceptions;
1583     }
1584     llvm_unreachable("bad destruction kind");
1585   }
1586 
1587   CleanupKind getCleanupKind(QualType::DestructionKind kind) {
1588     return (needsEHCleanup(kind) ? NormalAndEHCleanup : NormalCleanup);
1589   }
1590 
1591   //===--------------------------------------------------------------------===//
1592   //                                  Objective-C
1593   //===--------------------------------------------------------------------===//
1594 
1595   void GenerateObjCMethod(const ObjCMethodDecl *OMD);
1596 
1597   void StartObjCMethod(const ObjCMethodDecl *MD, const ObjCContainerDecl *CD);
1598 
1599   /// GenerateObjCGetter - Synthesize an Objective-C property getter function.
1600   void GenerateObjCGetter(ObjCImplementationDecl *IMP,
1601                           const ObjCPropertyImplDecl *PID);
1602   void generateObjCGetterBody(const ObjCImplementationDecl *classImpl,
1603                               const ObjCPropertyImplDecl *propImpl,
1604                               const ObjCMethodDecl *GetterMothodDecl,
1605                               llvm::Constant *AtomicHelperFn);
1606 
1607   void GenerateObjCCtorDtorMethod(ObjCImplementationDecl *IMP,
1608                                   ObjCMethodDecl *MD, bool ctor);
1609 
1610   /// GenerateObjCSetter - Synthesize an Objective-C property setter function
1611   /// for the given property.
1612   void GenerateObjCSetter(ObjCImplementationDecl *IMP,
1613                           const ObjCPropertyImplDecl *PID);
1614   void generateObjCSetterBody(const ObjCImplementationDecl *classImpl,
1615                               const ObjCPropertyImplDecl *propImpl,
1616                               llvm::Constant *AtomicHelperFn);
1617 
1618   //===--------------------------------------------------------------------===//
1619   //                                  Block Bits
1620   //===--------------------------------------------------------------------===//
1621 
1622   /// Emit block literal.
1623   /// \return an LLVM value which is a pointer to a struct which contains
1624   /// information about the block, including the block invoke function, the
1625   /// captured variables, etc.
1626   llvm::Value *EmitBlockLiteral(const BlockExpr *);
1627   static void destroyBlockInfos(CGBlockInfo *info);
1628 
1629   llvm::Function *GenerateBlockFunction(GlobalDecl GD,
1630                                         const CGBlockInfo &Info,
1631                                         const DeclMapTy &ldm,
1632                                         bool IsLambdaConversionToBlock,
1633                                         bool BuildGlobalBlock);
1634 
1635   llvm::Constant *GenerateCopyHelperFunction(const CGBlockInfo &blockInfo);
1636   llvm::Constant *GenerateDestroyHelperFunction(const CGBlockInfo &blockInfo);
1637   llvm::Constant *GenerateObjCAtomicSetterCopyHelperFunction(
1638                                              const ObjCPropertyImplDecl *PID);
1639   llvm::Constant *GenerateObjCAtomicGetterCopyHelperFunction(
1640                                              const ObjCPropertyImplDecl *PID);
1641   llvm::Value *EmitBlockCopyAndAutorelease(llvm::Value *Block, QualType Ty);
1642 
1643   void BuildBlockRelease(llvm::Value *DeclPtr, BlockFieldFlags flags);
1644 
1645   class AutoVarEmission;
1646 
1647   void emitByrefStructureInit(const AutoVarEmission &emission);
1648   void enterByrefCleanup(const AutoVarEmission &emission);
1649 
1650   void setBlockContextParameter(const ImplicitParamDecl *D, unsigned argNum,
1651                                 llvm::Value *ptr);
1652 
1653   Address LoadBlockStruct();
1654   Address GetAddrOfBlockDecl(const VarDecl *var, bool ByRef);
1655 
1656   /// BuildBlockByrefAddress - Computes the location of the
1657   /// data in a variable which is declared as __block.
1658   Address emitBlockByrefAddress(Address baseAddr, const VarDecl *V,
1659                                 bool followForward = true);
1660   Address emitBlockByrefAddress(Address baseAddr,
1661                                 const BlockByrefInfo &info,
1662                                 bool followForward,
1663                                 const llvm::Twine &name);
1664 
1665   const BlockByrefInfo &getBlockByrefInfo(const VarDecl *var);
1666 
1667   QualType BuildFunctionArgList(GlobalDecl GD, FunctionArgList &Args);
1668 
1669   void GenerateCode(GlobalDecl GD, llvm::Function *Fn,
1670                     const CGFunctionInfo &FnInfo);
1671   /// Emit code for the start of a function.
1672   /// \param Loc       The location to be associated with the function.
1673   /// \param StartLoc  The location of the function body.
1674   void StartFunction(GlobalDecl GD,
1675                      QualType RetTy,
1676                      llvm::Function *Fn,
1677                      const CGFunctionInfo &FnInfo,
1678                      const FunctionArgList &Args,
1679                      SourceLocation Loc = SourceLocation(),
1680                      SourceLocation StartLoc = SourceLocation());
1681 
1682   static bool IsConstructorDelegationValid(const CXXConstructorDecl *Ctor);
1683 
1684   void EmitConstructorBody(FunctionArgList &Args);
1685   void EmitDestructorBody(FunctionArgList &Args);
1686   void emitImplicitAssignmentOperatorBody(FunctionArgList &Args);
1687   void EmitFunctionBody(FunctionArgList &Args, const Stmt *Body);
1688   void EmitBlockWithFallThrough(llvm::BasicBlock *BB, const Stmt *S);
1689 
1690   void EmitForwardingCallToLambda(const CXXMethodDecl *LambdaCallOperator,
1691                                   CallArgList &CallArgs);
1692   void EmitLambdaBlockInvokeBody();
1693   void EmitLambdaDelegatingInvokeBody(const CXXMethodDecl *MD);
1694   void EmitLambdaStaticInvokeBody(const CXXMethodDecl *MD);
1695   void EmitAsanPrologueOrEpilogue(bool Prologue);
1696 
1697   /// Emit the unified return block, trying to avoid its emission when
1698   /// possible.
1699   /// \return The debug location of the user written return statement if the
1700   /// return block is is avoided.
1701   llvm::DebugLoc EmitReturnBlock();
1702 
1703   /// FinishFunction - Complete IR generation of the current function. It is
1704   /// legal to call this function even if there is no current insertion point.
1705   void FinishFunction(SourceLocation EndLoc=SourceLocation());
1706 
1707   void StartThunk(llvm::Function *Fn, GlobalDecl GD,
1708                   const CGFunctionInfo &FnInfo, bool IsUnprototyped);
1709 
1710   void EmitCallAndReturnForThunk(llvm::Constant *Callee, const ThunkInfo *Thunk,
1711                                  bool IsUnprototyped);
1712 
1713   void FinishThunk();
1714 
1715   /// Emit a musttail call for a thunk with a potentially adjusted this pointer.
1716   void EmitMustTailThunk(const CXXMethodDecl *MD, llvm::Value *AdjustedThisPtr,
1717                          llvm::Value *Callee);
1718 
1719   /// Generate a thunk for the given method.
1720   void generateThunk(llvm::Function *Fn, const CGFunctionInfo &FnInfo,
1721                      GlobalDecl GD, const ThunkInfo &Thunk,
1722                      bool IsUnprototyped);
1723 
1724   llvm::Function *GenerateVarArgsThunk(llvm::Function *Fn,
1725                                        const CGFunctionInfo &FnInfo,
1726                                        GlobalDecl GD, const ThunkInfo &Thunk);
1727 
1728   void EmitCtorPrologue(const CXXConstructorDecl *CD, CXXCtorType Type,
1729                         FunctionArgList &Args);
1730 
1731   void EmitInitializerForField(FieldDecl *Field, LValue LHS, Expr *Init);
1732 
1733   /// Struct with all information about dynamic [sub]class needed to set vptr.
1734   struct VPtr {
1735     BaseSubobject Base;
1736     const CXXRecordDecl *NearestVBase;
1737     CharUnits OffsetFromNearestVBase;
1738     const CXXRecordDecl *VTableClass;
1739   };
1740 
1741   /// Initialize the vtable pointer of the given subobject.
1742   void InitializeVTablePointer(const VPtr &vptr);
1743 
1744   typedef llvm::SmallVector<VPtr, 4> VPtrsVector;
1745 
1746   typedef llvm::SmallPtrSet<const CXXRecordDecl *, 4> VisitedVirtualBasesSetTy;
1747   VPtrsVector getVTablePointers(const CXXRecordDecl *VTableClass);
1748 
1749   void getVTablePointers(BaseSubobject Base, const CXXRecordDecl *NearestVBase,
1750                          CharUnits OffsetFromNearestVBase,
1751                          bool BaseIsNonVirtualPrimaryBase,
1752                          const CXXRecordDecl *VTableClass,
1753                          VisitedVirtualBasesSetTy &VBases, VPtrsVector &vptrs);
1754 
1755   void InitializeVTablePointers(const CXXRecordDecl *ClassDecl);
1756 
1757   /// GetVTablePtr - Return the Value of the vtable pointer member pointed
1758   /// to by This.
1759   llvm::Value *GetVTablePtr(Address This, llvm::Type *VTableTy,
1760                             const CXXRecordDecl *VTableClass);
1761 
1762   enum CFITypeCheckKind {
1763     CFITCK_VCall,
1764     CFITCK_NVCall,
1765     CFITCK_DerivedCast,
1766     CFITCK_UnrelatedCast,
1767     CFITCK_ICall,
1768   };
1769 
1770   /// Derived is the presumed address of an object of type T after a
1771   /// cast. If T is a polymorphic class type, emit a check that the virtual
1772   /// table for Derived belongs to a class derived from T.
1773   void EmitVTablePtrCheckForCast(QualType T, llvm::Value *Derived,
1774                                  bool MayBeNull, CFITypeCheckKind TCK,
1775                                  SourceLocation Loc);
1776 
1777   /// EmitVTablePtrCheckForCall - Virtual method MD is being called via VTable.
1778   /// If vptr CFI is enabled, emit a check that VTable is valid.
1779   void EmitVTablePtrCheckForCall(const CXXRecordDecl *RD, llvm::Value *VTable,
1780                                  CFITypeCheckKind TCK, SourceLocation Loc);
1781 
1782   /// EmitVTablePtrCheck - Emit a check that VTable is a valid virtual table for
1783   /// RD using llvm.type.test.
1784   void EmitVTablePtrCheck(const CXXRecordDecl *RD, llvm::Value *VTable,
1785                           CFITypeCheckKind TCK, SourceLocation Loc);
1786 
1787   /// If whole-program virtual table optimization is enabled, emit an assumption
1788   /// that VTable is a member of RD's type identifier. Or, if vptr CFI is
1789   /// enabled, emit a check that VTable is a member of RD's type identifier.
1790   void EmitTypeMetadataCodeForVCall(const CXXRecordDecl *RD,
1791                                     llvm::Value *VTable, SourceLocation Loc);
1792 
1793   /// Returns whether we should perform a type checked load when loading a
1794   /// virtual function for virtual calls to members of RD. This is generally
1795   /// true when both vcall CFI and whole-program-vtables are enabled.
1796   bool ShouldEmitVTableTypeCheckedLoad(const CXXRecordDecl *RD);
1797 
1798   /// Emit a type checked load from the given vtable.
1799   llvm::Value *EmitVTableTypeCheckedLoad(const CXXRecordDecl *RD, llvm::Value *VTable,
1800                                          uint64_t VTableByteOffset);
1801 
1802   /// EnterDtorCleanups - Enter the cleanups necessary to complete the
1803   /// given phase of destruction for a destructor.  The end result
1804   /// should call destructors on members and base classes in reverse
1805   /// order of their construction.
1806   void EnterDtorCleanups(const CXXDestructorDecl *Dtor, CXXDtorType Type);
1807 
1808   /// ShouldInstrumentFunction - Return true if the current function should be
1809   /// instrumented with __cyg_profile_func_* calls
1810   bool ShouldInstrumentFunction();
1811 
1812   /// ShouldXRayInstrument - Return true if the current function should be
1813   /// instrumented with XRay nop sleds.
1814   bool ShouldXRayInstrumentFunction() const;
1815 
1816   /// AlwaysEmitXRayCustomEvents - Return true if we must unconditionally emit
1817   /// XRay custom event handling calls.
1818   bool AlwaysEmitXRayCustomEvents() const;
1819 
1820   /// AlwaysEmitXRayTypedEvents - Return true if clang must unconditionally emit
1821   /// XRay typed event handling calls.
1822   bool AlwaysEmitXRayTypedEvents() const;
1823 
1824   /// Encode an address into a form suitable for use in a function prologue.
1825   llvm::Constant *EncodeAddrForUseInPrologue(llvm::Function *F,
1826                                              llvm::Constant *Addr);
1827 
1828   /// Decode an address used in a function prologue, encoded by \c
1829   /// EncodeAddrForUseInPrologue.
1830   llvm::Value *DecodeAddrUsedInPrologue(llvm::Value *F,
1831                                         llvm::Value *EncodedAddr);
1832 
1833   /// EmitFunctionProlog - Emit the target specific LLVM code to load the
1834   /// arguments for the given function. This is also responsible for naming the
1835   /// LLVM function arguments.
1836   void EmitFunctionProlog(const CGFunctionInfo &FI,
1837                           llvm::Function *Fn,
1838                           const FunctionArgList &Args);
1839 
1840   /// EmitFunctionEpilog - Emit the target specific LLVM code to return the
1841   /// given temporary.
1842   void EmitFunctionEpilog(const CGFunctionInfo &FI, bool EmitRetDbgLoc,
1843                           SourceLocation EndLoc);
1844 
1845   /// Emit a test that checks if the return value \p RV is nonnull.
1846   void EmitReturnValueCheck(llvm::Value *RV);
1847 
1848   /// EmitStartEHSpec - Emit the start of the exception spec.
1849   void EmitStartEHSpec(const Decl *D);
1850 
1851   /// EmitEndEHSpec - Emit the end of the exception spec.
1852   void EmitEndEHSpec(const Decl *D);
1853 
1854   /// getTerminateLandingPad - Return a landing pad that just calls terminate.
1855   llvm::BasicBlock *getTerminateLandingPad();
1856 
1857   /// getTerminateLandingPad - Return a cleanup funclet that just calls
1858   /// terminate.
1859   llvm::BasicBlock *getTerminateFunclet();
1860 
1861   /// getTerminateHandler - Return a handler (not a landing pad, just
1862   /// a catch handler) that just calls terminate.  This is used when
1863   /// a terminate scope encloses a try.
1864   llvm::BasicBlock *getTerminateHandler();
1865 
1866   llvm::Type *ConvertTypeForMem(QualType T);
1867   llvm::Type *ConvertType(QualType T);
1868   llvm::Type *ConvertType(const TypeDecl *T) {
1869     return ConvertType(getContext().getTypeDeclType(T));
1870   }
1871 
1872   /// LoadObjCSelf - Load the value of self. This function is only valid while
1873   /// generating code for an Objective-C method.
1874   llvm::Value *LoadObjCSelf();
1875 
1876   /// TypeOfSelfObject - Return type of object that this self represents.
1877   QualType TypeOfSelfObject();
1878 
1879   /// getEvaluationKind - Return the TypeEvaluationKind of QualType \c T.
1880   static TypeEvaluationKind getEvaluationKind(QualType T);
1881 
1882   static bool hasScalarEvaluationKind(QualType T) {
1883     return getEvaluationKind(T) == TEK_Scalar;
1884   }
1885 
1886   static bool hasAggregateEvaluationKind(QualType T) {
1887     return getEvaluationKind(T) == TEK_Aggregate;
1888   }
1889 
1890   /// createBasicBlock - Create an LLVM basic block.
1891   llvm::BasicBlock *createBasicBlock(const Twine &name = "",
1892                                      llvm::Function *parent = nullptr,
1893                                      llvm::BasicBlock *before = nullptr) {
1894     return llvm::BasicBlock::Create(getLLVMContext(), name, parent, before);
1895   }
1896 
1897   /// getBasicBlockForLabel - Return the LLVM basicblock that the specified
1898   /// label maps to.
1899   JumpDest getJumpDestForLabel(const LabelDecl *S);
1900 
1901   /// SimplifyForwardingBlocks - If the given basic block is only a branch to
1902   /// another basic block, simplify it. This assumes that no other code could
1903   /// potentially reference the basic block.
1904   void SimplifyForwardingBlocks(llvm::BasicBlock *BB);
1905 
1906   /// EmitBlock - Emit the given block \arg BB and set it as the insert point,
1907   /// adding a fall-through branch from the current insert block if
1908   /// necessary. It is legal to call this function even if there is no current
1909   /// insertion point.
1910   ///
1911   /// IsFinished - If true, indicates that the caller has finished emitting
1912   /// branches to the given block and does not expect to emit code into it. This
1913   /// means the block can be ignored if it is unreachable.
1914   void EmitBlock(llvm::BasicBlock *BB, bool IsFinished=false);
1915 
1916   /// EmitBlockAfterUses - Emit the given block somewhere hopefully
1917   /// near its uses, and leave the insertion point in it.
1918   void EmitBlockAfterUses(llvm::BasicBlock *BB);
1919 
1920   /// EmitBranch - Emit a branch to the specified basic block from the current
1921   /// insert block, taking care to avoid creation of branches from dummy
1922   /// blocks. It is legal to call this function even if there is no current
1923   /// insertion point.
1924   ///
1925   /// This function clears the current insertion point. The caller should follow
1926   /// calls to this function with calls to Emit*Block prior to generation new
1927   /// code.
1928   void EmitBranch(llvm::BasicBlock *Block);
1929 
1930   /// HaveInsertPoint - True if an insertion point is defined. If not, this
1931   /// indicates that the current code being emitted is unreachable.
1932   bool HaveInsertPoint() const {
1933     return Builder.GetInsertBlock() != nullptr;
1934   }
1935 
1936   /// EnsureInsertPoint - Ensure that an insertion point is defined so that
1937   /// emitted IR has a place to go. Note that by definition, if this function
1938   /// creates a block then that block is unreachable; callers may do better to
1939   /// detect when no insertion point is defined and simply skip IR generation.
1940   void EnsureInsertPoint() {
1941     if (!HaveInsertPoint())
1942       EmitBlock(createBasicBlock());
1943   }
1944 
1945   /// ErrorUnsupported - Print out an error that codegen doesn't support the
1946   /// specified stmt yet.
1947   void ErrorUnsupported(const Stmt *S, const char *Type);
1948 
1949   //===--------------------------------------------------------------------===//
1950   //                                  Helpers
1951   //===--------------------------------------------------------------------===//
1952 
1953   LValue MakeAddrLValue(Address Addr, QualType T,
1954                         AlignmentSource Source = AlignmentSource::Type) {
1955     return LValue::MakeAddr(Addr, T, getContext(), LValueBaseInfo(Source),
1956                             CGM.getTBAAAccessInfo(T));
1957   }
1958 
1959   LValue MakeAddrLValue(Address Addr, QualType T, LValueBaseInfo BaseInfo,
1960                         TBAAAccessInfo TBAAInfo) {
1961     return LValue::MakeAddr(Addr, T, getContext(), BaseInfo, TBAAInfo);
1962   }
1963 
1964   LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment,
1965                         AlignmentSource Source = AlignmentSource::Type) {
1966     return LValue::MakeAddr(Address(V, Alignment), T, getContext(),
1967                             LValueBaseInfo(Source), CGM.getTBAAAccessInfo(T));
1968   }
1969 
1970   LValue MakeAddrLValue(llvm::Value *V, QualType T, CharUnits Alignment,
1971                         LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo) {
1972     return LValue::MakeAddr(Address(V, Alignment), T, getContext(),
1973                             BaseInfo, TBAAInfo);
1974   }
1975 
1976   LValue MakeNaturalAlignPointeeAddrLValue(llvm::Value *V, QualType T);
1977   LValue MakeNaturalAlignAddrLValue(llvm::Value *V, QualType T);
1978   CharUnits getNaturalTypeAlignment(QualType T,
1979                                     LValueBaseInfo *BaseInfo = nullptr,
1980                                     TBAAAccessInfo *TBAAInfo = nullptr,
1981                                     bool forPointeeType = false);
1982   CharUnits getNaturalPointeeTypeAlignment(QualType T,
1983                                            LValueBaseInfo *BaseInfo = nullptr,
1984                                            TBAAAccessInfo *TBAAInfo = nullptr);
1985 
1986   Address EmitLoadOfReference(LValue RefLVal,
1987                               LValueBaseInfo *PointeeBaseInfo = nullptr,
1988                               TBAAAccessInfo *PointeeTBAAInfo = nullptr);
1989   LValue EmitLoadOfReferenceLValue(LValue RefLVal);
1990   LValue EmitLoadOfReferenceLValue(Address RefAddr, QualType RefTy,
1991                                    AlignmentSource Source =
1992                                        AlignmentSource::Type) {
1993     LValue RefLVal = MakeAddrLValue(RefAddr, RefTy, LValueBaseInfo(Source),
1994                                     CGM.getTBAAAccessInfo(RefTy));
1995     return EmitLoadOfReferenceLValue(RefLVal);
1996   }
1997 
1998   Address EmitLoadOfPointer(Address Ptr, const PointerType *PtrTy,
1999                             LValueBaseInfo *BaseInfo = nullptr,
2000                             TBAAAccessInfo *TBAAInfo = nullptr);
2001   LValue EmitLoadOfPointerLValue(Address Ptr, const PointerType *PtrTy);
2002 
2003   /// CreateTempAlloca - This creates an alloca and inserts it into the entry
2004   /// block if \p ArraySize is nullptr, otherwise inserts it at the current
2005   /// insertion point of the builder. The caller is responsible for setting an
2006   /// appropriate alignment on
2007   /// the alloca.
2008   ///
2009   /// \p ArraySize is the number of array elements to be allocated if it
2010   ///    is not nullptr.
2011   ///
2012   /// LangAS::Default is the address space of pointers to local variables and
2013   /// temporaries, as exposed in the source language. In certain
2014   /// configurations, this is not the same as the alloca address space, and a
2015   /// cast is needed to lift the pointer from the alloca AS into
2016   /// LangAS::Default. This can happen when the target uses a restricted
2017   /// address space for the stack but the source language requires
2018   /// LangAS::Default to be a generic address space. The latter condition is
2019   /// common for most programming languages; OpenCL is an exception in that
2020   /// LangAS::Default is the private address space, which naturally maps
2021   /// to the stack.
2022   ///
2023   /// Because the address of a temporary is often exposed to the program in
2024   /// various ways, this function will perform the cast. The original alloca
2025   /// instruction is returned through \p Alloca if it is not nullptr.
2026   ///
2027   /// The cast is not performaed in CreateTempAllocaWithoutCast. This is
2028   /// more efficient if the caller knows that the address will not be exposed.
2029   llvm::AllocaInst *CreateTempAlloca(llvm::Type *Ty, const Twine &Name = "tmp",
2030                                      llvm::Value *ArraySize = nullptr);
2031   Address CreateTempAlloca(llvm::Type *Ty, CharUnits align,
2032                            const Twine &Name = "tmp",
2033                            llvm::Value *ArraySize = nullptr,
2034                            Address *Alloca = nullptr);
2035   Address CreateTempAllocaWithoutCast(llvm::Type *Ty, CharUnits align,
2036                                       const Twine &Name = "tmp",
2037                                       llvm::Value *ArraySize = nullptr);
2038 
2039   /// CreateDefaultAlignedTempAlloca - This creates an alloca with the
2040   /// default ABI alignment of the given LLVM type.
2041   ///
2042   /// IMPORTANT NOTE: This is *not* generally the right alignment for
2043   /// any given AST type that happens to have been lowered to the
2044   /// given IR type.  This should only ever be used for function-local,
2045   /// IR-driven manipulations like saving and restoring a value.  Do
2046   /// not hand this address off to arbitrary IRGen routines, and especially
2047   /// do not pass it as an argument to a function that might expect a
2048   /// properly ABI-aligned value.
2049   Address CreateDefaultAlignTempAlloca(llvm::Type *Ty,
2050                                        const Twine &Name = "tmp");
2051 
2052   /// InitTempAlloca - Provide an initial value for the given alloca which
2053   /// will be observable at all locations in the function.
2054   ///
2055   /// The address should be something that was returned from one of
2056   /// the CreateTempAlloca or CreateMemTemp routines, and the
2057   /// initializer must be valid in the entry block (i.e. it must
2058   /// either be a constant or an argument value).
2059   void InitTempAlloca(Address Alloca, llvm::Value *Value);
2060 
2061   /// CreateIRTemp - Create a temporary IR object of the given type, with
2062   /// appropriate alignment. This routine should only be used when an temporary
2063   /// value needs to be stored into an alloca (for example, to avoid explicit
2064   /// PHI construction), but the type is the IR type, not the type appropriate
2065   /// for storing in memory.
2066   ///
2067   /// That is, this is exactly equivalent to CreateMemTemp, but calling
2068   /// ConvertType instead of ConvertTypeForMem.
2069   Address CreateIRTemp(QualType T, const Twine &Name = "tmp");
2070 
2071   /// CreateMemTemp - Create a temporary memory object of the given type, with
2072   /// appropriate alignmen and cast it to the default address space. Returns
2073   /// the original alloca instruction by \p Alloca if it is not nullptr.
2074   Address CreateMemTemp(QualType T, const Twine &Name = "tmp",
2075                         Address *Alloca = nullptr);
2076   Address CreateMemTemp(QualType T, CharUnits Align, const Twine &Name = "tmp",
2077                         Address *Alloca = nullptr);
2078 
2079   /// CreateMemTemp - Create a temporary memory object of the given type, with
2080   /// appropriate alignmen without casting it to the default address space.
2081   Address CreateMemTempWithoutCast(QualType T, const Twine &Name = "tmp");
2082   Address CreateMemTempWithoutCast(QualType T, CharUnits Align,
2083                                    const Twine &Name = "tmp");
2084 
2085   /// CreateAggTemp - Create a temporary memory object for the given
2086   /// aggregate type.
2087   AggValueSlot CreateAggTemp(QualType T, const Twine &Name = "tmp") {
2088     return AggValueSlot::forAddr(CreateMemTemp(T, Name),
2089                                  T.getQualifiers(),
2090                                  AggValueSlot::IsNotDestructed,
2091                                  AggValueSlot::DoesNotNeedGCBarriers,
2092                                  AggValueSlot::IsNotAliased,
2093                                  AggValueSlot::DoesNotOverlap);
2094   }
2095 
2096   /// Emit a cast to void* in the appropriate address space.
2097   llvm::Value *EmitCastToVoidPtr(llvm::Value *value);
2098 
2099   /// EvaluateExprAsBool - Perform the usual unary conversions on the specified
2100   /// expression and compare the result against zero, returning an Int1Ty value.
2101   llvm::Value *EvaluateExprAsBool(const Expr *E);
2102 
2103   /// EmitIgnoredExpr - Emit an expression in a context which ignores the result.
2104   void EmitIgnoredExpr(const Expr *E);
2105 
2106   /// EmitAnyExpr - Emit code to compute the specified expression which can have
2107   /// any type.  The result is returned as an RValue struct.  If this is an
2108   /// aggregate expression, the aggloc/agglocvolatile arguments indicate where
2109   /// the result should be returned.
2110   ///
2111   /// \param ignoreResult True if the resulting value isn't used.
2112   RValue EmitAnyExpr(const Expr *E,
2113                      AggValueSlot aggSlot = AggValueSlot::ignored(),
2114                      bool ignoreResult = false);
2115 
2116   // EmitVAListRef - Emit a "reference" to a va_list; this is either the address
2117   // or the value of the expression, depending on how va_list is defined.
2118   Address EmitVAListRef(const Expr *E);
2119 
2120   /// Emit a "reference" to a __builtin_ms_va_list; this is
2121   /// always the value of the expression, because a __builtin_ms_va_list is a
2122   /// pointer to a char.
2123   Address EmitMSVAListRef(const Expr *E);
2124 
2125   /// EmitAnyExprToTemp - Similarly to EmitAnyExpr(), however, the result will
2126   /// always be accessible even if no aggregate location is provided.
2127   RValue EmitAnyExprToTemp(const Expr *E);
2128 
2129   /// EmitAnyExprToMem - Emits the code necessary to evaluate an
2130   /// arbitrary expression into the given memory location.
2131   void EmitAnyExprToMem(const Expr *E, Address Location,
2132                         Qualifiers Quals, bool IsInitializer);
2133 
2134   void EmitAnyExprToExn(const Expr *E, Address Addr);
2135 
2136   /// EmitExprAsInit - Emits the code necessary to initialize a
2137   /// location in memory with the given initializer.
2138   void EmitExprAsInit(const Expr *init, const ValueDecl *D, LValue lvalue,
2139                       bool capturedByInit);
2140 
2141   /// hasVolatileMember - returns true if aggregate type has a volatile
2142   /// member.
2143   bool hasVolatileMember(QualType T) {
2144     if (const RecordType *RT = T->getAs<RecordType>()) {
2145       const RecordDecl *RD = cast<RecordDecl>(RT->getDecl());
2146       return RD->hasVolatileMember();
2147     }
2148     return false;
2149   }
2150 
2151   /// Determine whether a return value slot may overlap some other object.
2152   AggValueSlot::Overlap_t overlapForReturnValue() {
2153     // FIXME: Assuming no overlap here breaks guaranteed copy elision for base
2154     // class subobjects. These cases may need to be revisited depending on the
2155     // resolution of the relevant core issue.
2156     return AggValueSlot::DoesNotOverlap;
2157   }
2158 
2159   /// Determine whether a field initialization may overlap some other object.
2160   AggValueSlot::Overlap_t overlapForFieldInit(const FieldDecl *FD) {
2161     // FIXME: These cases can result in overlap as a result of P0840R0's
2162     // [[no_unique_address]] attribute. We can still infer NoOverlap in the
2163     // presence of that attribute if the field is within the nvsize of its
2164     // containing class, because non-virtual subobjects are initialized in
2165     // address order.
2166     return AggValueSlot::DoesNotOverlap;
2167   }
2168 
2169   /// Determine whether a base class initialization may overlap some other
2170   /// object.
2171   AggValueSlot::Overlap_t overlapForBaseInit(const CXXRecordDecl *RD,
2172                                              const CXXRecordDecl *BaseRD,
2173                                              bool IsVirtual);
2174 
2175   /// Emit an aggregate assignment.
2176   void EmitAggregateAssign(LValue Dest, LValue Src, QualType EltTy) {
2177     bool IsVolatile = hasVolatileMember(EltTy);
2178     EmitAggregateCopy(Dest, Src, EltTy, AggValueSlot::MayOverlap, IsVolatile);
2179   }
2180 
2181   void EmitAggregateCopyCtor(LValue Dest, LValue Src,
2182                              AggValueSlot::Overlap_t MayOverlap) {
2183     EmitAggregateCopy(Dest, Src, Src.getType(), MayOverlap);
2184   }
2185 
2186   /// EmitAggregateCopy - Emit an aggregate copy.
2187   ///
2188   /// \param isVolatile \c true iff either the source or the destination is
2189   ///        volatile.
2190   /// \param MayOverlap Whether the tail padding of the destination might be
2191   ///        occupied by some other object. More efficient code can often be
2192   ///        generated if not.
2193   void EmitAggregateCopy(LValue Dest, LValue Src, QualType EltTy,
2194                          AggValueSlot::Overlap_t MayOverlap,
2195                          bool isVolatile = false);
2196 
2197   /// GetAddrOfLocalVar - Return the address of a local variable.
2198   Address GetAddrOfLocalVar(const VarDecl *VD) {
2199     auto it = LocalDeclMap.find(VD);
2200     assert(it != LocalDeclMap.end() &&
2201            "Invalid argument to GetAddrOfLocalVar(), no decl!");
2202     return it->second;
2203   }
2204 
2205   /// Given an opaque value expression, return its LValue mapping if it exists,
2206   /// otherwise create one.
2207   LValue getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e);
2208 
2209   /// Given an opaque value expression, return its RValue mapping if it exists,
2210   /// otherwise create one.
2211   RValue getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e);
2212 
2213   /// Get the index of the current ArrayInitLoopExpr, if any.
2214   llvm::Value *getArrayInitIndex() { return ArrayInitIndex; }
2215 
2216   /// getAccessedFieldNo - Given an encoded value and a result number, return
2217   /// the input field number being accessed.
2218   static unsigned getAccessedFieldNo(unsigned Idx, const llvm::Constant *Elts);
2219 
2220   llvm::BlockAddress *GetAddrOfLabel(const LabelDecl *L);
2221   llvm::BasicBlock *GetIndirectGotoBlock();
2222 
2223   /// Check if \p E is a C++ "this" pointer wrapped in value-preserving casts.
2224   static bool IsWrappedCXXThis(const Expr *E);
2225 
2226   /// EmitNullInitialization - Generate code to set a value of the given type to
2227   /// null, If the type contains data member pointers, they will be initialized
2228   /// to -1 in accordance with the Itanium C++ ABI.
2229   void EmitNullInitialization(Address DestPtr, QualType Ty);
2230 
2231   /// Emits a call to an LLVM variable-argument intrinsic, either
2232   /// \c llvm.va_start or \c llvm.va_end.
2233   /// \param ArgValue A reference to the \c va_list as emitted by either
2234   /// \c EmitVAListRef or \c EmitMSVAListRef.
2235   /// \param IsStart If \c true, emits a call to \c llvm.va_start; otherwise,
2236   /// calls \c llvm.va_end.
2237   llvm::Value *EmitVAStartEnd(llvm::Value *ArgValue, bool IsStart);
2238 
2239   /// Generate code to get an argument from the passed in pointer
2240   /// and update it accordingly.
2241   /// \param VE The \c VAArgExpr for which to generate code.
2242   /// \param VAListAddr Receives a reference to the \c va_list as emitted by
2243   /// either \c EmitVAListRef or \c EmitMSVAListRef.
2244   /// \returns A pointer to the argument.
2245   // FIXME: We should be able to get rid of this method and use the va_arg
2246   // instruction in LLVM instead once it works well enough.
2247   Address EmitVAArg(VAArgExpr *VE, Address &VAListAddr);
2248 
2249   /// emitArrayLength - Compute the length of an array, even if it's a
2250   /// VLA, and drill down to the base element type.
2251   llvm::Value *emitArrayLength(const ArrayType *arrayType,
2252                                QualType &baseType,
2253                                Address &addr);
2254 
2255   /// EmitVLASize - Capture all the sizes for the VLA expressions in
2256   /// the given variably-modified type and store them in the VLASizeMap.
2257   ///
2258   /// This function can be called with a null (unreachable) insert point.
2259   void EmitVariablyModifiedType(QualType Ty);
2260 
2261   struct VlaSizePair {
2262     llvm::Value *NumElts;
2263     QualType Type;
2264 
2265     VlaSizePair(llvm::Value *NE, QualType T) : NumElts(NE), Type(T) {}
2266   };
2267 
2268   /// Return the number of elements for a single dimension
2269   /// for the given array type.
2270   VlaSizePair getVLAElements1D(const VariableArrayType *vla);
2271   VlaSizePair getVLAElements1D(QualType vla);
2272 
2273   /// Returns an LLVM value that corresponds to the size,
2274   /// in non-variably-sized elements, of a variable length array type,
2275   /// plus that largest non-variably-sized element type.  Assumes that
2276   /// the type has already been emitted with EmitVariablyModifiedType.
2277   VlaSizePair getVLASize(const VariableArrayType *vla);
2278   VlaSizePair getVLASize(QualType vla);
2279 
2280   /// LoadCXXThis - Load the value of 'this'. This function is only valid while
2281   /// generating code for an C++ member function.
2282   llvm::Value *LoadCXXThis() {
2283     assert(CXXThisValue && "no 'this' value for this function");
2284     return CXXThisValue;
2285   }
2286   Address LoadCXXThisAddress();
2287 
2288   /// LoadCXXVTT - Load the VTT parameter to base constructors/destructors have
2289   /// virtual bases.
2290   // FIXME: Every place that calls LoadCXXVTT is something
2291   // that needs to be abstracted properly.
2292   llvm::Value *LoadCXXVTT() {
2293     assert(CXXStructorImplicitParamValue && "no VTT value for this function");
2294     return CXXStructorImplicitParamValue;
2295   }
2296 
2297   /// GetAddressOfBaseOfCompleteClass - Convert the given pointer to a
2298   /// complete class to the given direct base.
2299   Address
2300   GetAddressOfDirectBaseInCompleteClass(Address Value,
2301                                         const CXXRecordDecl *Derived,
2302                                         const CXXRecordDecl *Base,
2303                                         bool BaseIsVirtual);
2304 
2305   static bool ShouldNullCheckClassCastValue(const CastExpr *Cast);
2306 
2307   /// GetAddressOfBaseClass - This function will add the necessary delta to the
2308   /// load of 'this' and returns address of the base class.
2309   Address GetAddressOfBaseClass(Address Value,
2310                                 const CXXRecordDecl *Derived,
2311                                 CastExpr::path_const_iterator PathBegin,
2312                                 CastExpr::path_const_iterator PathEnd,
2313                                 bool NullCheckValue, SourceLocation Loc);
2314 
2315   Address GetAddressOfDerivedClass(Address Value,
2316                                    const CXXRecordDecl *Derived,
2317                                    CastExpr::path_const_iterator PathBegin,
2318                                    CastExpr::path_const_iterator PathEnd,
2319                                    bool NullCheckValue);
2320 
2321   /// GetVTTParameter - Return the VTT parameter that should be passed to a
2322   /// base constructor/destructor with virtual bases.
2323   /// FIXME: VTTs are Itanium ABI-specific, so the definition should move
2324   /// to ItaniumCXXABI.cpp together with all the references to VTT.
2325   llvm::Value *GetVTTParameter(GlobalDecl GD, bool ForVirtualBase,
2326                                bool Delegating);
2327 
2328   void EmitDelegateCXXConstructorCall(const CXXConstructorDecl *Ctor,
2329                                       CXXCtorType CtorType,
2330                                       const FunctionArgList &Args,
2331                                       SourceLocation Loc);
2332   // It's important not to confuse this and the previous function. Delegating
2333   // constructors are the C++0x feature. The constructor delegate optimization
2334   // is used to reduce duplication in the base and complete consturctors where
2335   // they are substantially the same.
2336   void EmitDelegatingCXXConstructorCall(const CXXConstructorDecl *Ctor,
2337                                         const FunctionArgList &Args);
2338 
2339   /// Emit a call to an inheriting constructor (that is, one that invokes a
2340   /// constructor inherited from a base class) by inlining its definition. This
2341   /// is necessary if the ABI does not support forwarding the arguments to the
2342   /// base class constructor (because they're variadic or similar).
2343   void EmitInlinedInheritingCXXConstructorCall(const CXXConstructorDecl *Ctor,
2344                                                CXXCtorType CtorType,
2345                                                bool ForVirtualBase,
2346                                                bool Delegating,
2347                                                CallArgList &Args);
2348 
2349   /// Emit a call to a constructor inherited from a base class, passing the
2350   /// current constructor's arguments along unmodified (without even making
2351   /// a copy).
2352   void EmitInheritedCXXConstructorCall(const CXXConstructorDecl *D,
2353                                        bool ForVirtualBase, Address This,
2354                                        bool InheritedFromVBase,
2355                                        const CXXInheritedCtorInitExpr *E);
2356 
2357   void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
2358                               bool ForVirtualBase, bool Delegating,
2359                               Address This, const CXXConstructExpr *E,
2360                               AggValueSlot::Overlap_t Overlap);
2361 
2362   void EmitCXXConstructorCall(const CXXConstructorDecl *D, CXXCtorType Type,
2363                               bool ForVirtualBase, bool Delegating,
2364                               Address This, CallArgList &Args,
2365                               AggValueSlot::Overlap_t Overlap,
2366                               SourceLocation Loc);
2367 
2368   /// Emit assumption load for all bases. Requires to be be called only on
2369   /// most-derived class and not under construction of the object.
2370   void EmitVTableAssumptionLoads(const CXXRecordDecl *ClassDecl, Address This);
2371 
2372   /// Emit assumption that vptr load == global vtable.
2373   void EmitVTableAssumptionLoad(const VPtr &vptr, Address This);
2374 
2375   void EmitSynthesizedCXXCopyCtorCall(const CXXConstructorDecl *D,
2376                                       Address This, Address Src,
2377                                       const CXXConstructExpr *E);
2378 
2379   void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
2380                                   const ArrayType *ArrayTy,
2381                                   Address ArrayPtr,
2382                                   const CXXConstructExpr *E,
2383                                   bool ZeroInitialization = false);
2384 
2385   void EmitCXXAggrConstructorCall(const CXXConstructorDecl *D,
2386                                   llvm::Value *NumElements,
2387                                   Address ArrayPtr,
2388                                   const CXXConstructExpr *E,
2389                                   bool ZeroInitialization = false);
2390 
2391   static Destroyer destroyCXXObject;
2392 
2393   void EmitCXXDestructorCall(const CXXDestructorDecl *D, CXXDtorType Type,
2394                              bool ForVirtualBase, bool Delegating,
2395                              Address This);
2396 
2397   void EmitNewArrayInitializer(const CXXNewExpr *E, QualType elementType,
2398                                llvm::Type *ElementTy, Address NewPtr,
2399                                llvm::Value *NumElements,
2400                                llvm::Value *AllocSizeWithoutCookie);
2401 
2402   void EmitCXXTemporary(const CXXTemporary *Temporary, QualType TempType,
2403                         Address Ptr);
2404 
2405   llvm::Value *EmitLifetimeStart(uint64_t Size, llvm::Value *Addr);
2406   void EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr);
2407 
2408   llvm::Value *EmitCXXNewExpr(const CXXNewExpr *E);
2409   void EmitCXXDeleteExpr(const CXXDeleteExpr *E);
2410 
2411   void EmitDeleteCall(const FunctionDecl *DeleteFD, llvm::Value *Ptr,
2412                       QualType DeleteTy, llvm::Value *NumElements = nullptr,
2413                       CharUnits CookieSize = CharUnits());
2414 
2415   RValue EmitBuiltinNewDeleteCall(const FunctionProtoType *Type,
2416                                   const CallExpr *TheCallExpr, bool IsDelete);
2417 
2418   llvm::Value *EmitCXXTypeidExpr(const CXXTypeidExpr *E);
2419   llvm::Value *EmitDynamicCast(Address V, const CXXDynamicCastExpr *DCE);
2420   Address EmitCXXUuidofExpr(const CXXUuidofExpr *E);
2421 
2422   /// Situations in which we might emit a check for the suitability of a
2423   ///        pointer or glvalue.
2424   enum TypeCheckKind {
2425     /// Checking the operand of a load. Must be suitably sized and aligned.
2426     TCK_Load,
2427     /// Checking the destination of a store. Must be suitably sized and aligned.
2428     TCK_Store,
2429     /// Checking the bound value in a reference binding. Must be suitably sized
2430     /// and aligned, but is not required to refer to an object (until the
2431     /// reference is used), per core issue 453.
2432     TCK_ReferenceBinding,
2433     /// Checking the object expression in a non-static data member access. Must
2434     /// be an object within its lifetime.
2435     TCK_MemberAccess,
2436     /// Checking the 'this' pointer for a call to a non-static member function.
2437     /// Must be an object within its lifetime.
2438     TCK_MemberCall,
2439     /// Checking the 'this' pointer for a constructor call.
2440     TCK_ConstructorCall,
2441     /// Checking the operand of a static_cast to a derived pointer type. Must be
2442     /// null or an object within its lifetime.
2443     TCK_DowncastPointer,
2444     /// Checking the operand of a static_cast to a derived reference type. Must
2445     /// be an object within its lifetime.
2446     TCK_DowncastReference,
2447     /// Checking the operand of a cast to a base object. Must be suitably sized
2448     /// and aligned.
2449     TCK_Upcast,
2450     /// Checking the operand of a cast to a virtual base object. Must be an
2451     /// object within its lifetime.
2452     TCK_UpcastToVirtualBase,
2453     /// Checking the value assigned to a _Nonnull pointer. Must not be null.
2454     TCK_NonnullAssign,
2455     /// Checking the operand of a dynamic_cast or a typeid expression.  Must be
2456     /// null or an object within its lifetime.
2457     TCK_DynamicOperation
2458   };
2459 
2460   /// Determine whether the pointer type check \p TCK permits null pointers.
2461   static bool isNullPointerAllowed(TypeCheckKind TCK);
2462 
2463   /// Determine whether the pointer type check \p TCK requires a vptr check.
2464   static bool isVptrCheckRequired(TypeCheckKind TCK, QualType Ty);
2465 
2466   /// Whether any type-checking sanitizers are enabled. If \c false,
2467   /// calls to EmitTypeCheck can be skipped.
2468   bool sanitizePerformTypeCheck() const;
2469 
2470   /// Emit a check that \p V is the address of storage of the
2471   /// appropriate size and alignment for an object of type \p Type.
2472   void EmitTypeCheck(TypeCheckKind TCK, SourceLocation Loc, llvm::Value *V,
2473                      QualType Type, CharUnits Alignment = CharUnits::Zero(),
2474                      SanitizerSet SkippedChecks = SanitizerSet());
2475 
2476   /// Emit a check that \p Base points into an array object, which
2477   /// we can access at index \p Index. \p Accessed should be \c false if we
2478   /// this expression is used as an lvalue, for instance in "&Arr[Idx]".
2479   void EmitBoundsCheck(const Expr *E, const Expr *Base, llvm::Value *Index,
2480                        QualType IndexType, bool Accessed);
2481 
2482   llvm::Value *EmitScalarPrePostIncDec(const UnaryOperator *E, LValue LV,
2483                                        bool isInc, bool isPre);
2484   ComplexPairTy EmitComplexPrePostIncDec(const UnaryOperator *E, LValue LV,
2485                                          bool isInc, bool isPre);
2486 
2487   void EmitAlignmentAssumption(llvm::Value *PtrValue, unsigned Alignment,
2488                                llvm::Value *OffsetValue = nullptr) {
2489     Builder.CreateAlignmentAssumption(CGM.getDataLayout(), PtrValue, Alignment,
2490                                       OffsetValue);
2491   }
2492 
2493   /// Converts Location to a DebugLoc, if debug information is enabled.
2494   llvm::DebugLoc SourceLocToDebugLoc(SourceLocation Location);
2495 
2496 
2497   //===--------------------------------------------------------------------===//
2498   //                            Declaration Emission
2499   //===--------------------------------------------------------------------===//
2500 
2501   /// EmitDecl - Emit a declaration.
2502   ///
2503   /// This function can be called with a null (unreachable) insert point.
2504   void EmitDecl(const Decl &D);
2505 
2506   /// EmitVarDecl - Emit a local variable declaration.
2507   ///
2508   /// This function can be called with a null (unreachable) insert point.
2509   void EmitVarDecl(const VarDecl &D);
2510 
2511   void EmitScalarInit(const Expr *init, const ValueDecl *D, LValue lvalue,
2512                       bool capturedByInit);
2513 
2514   typedef void SpecialInitFn(CodeGenFunction &Init, const VarDecl &D,
2515                              llvm::Value *Address);
2516 
2517   /// Determine whether the given initializer is trivial in the sense
2518   /// that it requires no code to be generated.
2519   bool isTrivialInitializer(const Expr *Init);
2520 
2521   /// EmitAutoVarDecl - Emit an auto variable declaration.
2522   ///
2523   /// This function can be called with a null (unreachable) insert point.
2524   void EmitAutoVarDecl(const VarDecl &D);
2525 
2526   class AutoVarEmission {
2527     friend class CodeGenFunction;
2528 
2529     const VarDecl *Variable;
2530 
2531     /// The address of the alloca for languages with explicit address space
2532     /// (e.g. OpenCL) or alloca casted to generic pointer for address space
2533     /// agnostic languages (e.g. C++). Invalid if the variable was emitted
2534     /// as a global constant.
2535     Address Addr;
2536 
2537     llvm::Value *NRVOFlag;
2538 
2539     /// True if the variable is a __block variable.
2540     bool IsByRef;
2541 
2542     /// True if the variable is of aggregate type and has a constant
2543     /// initializer.
2544     bool IsConstantAggregate;
2545 
2546     /// Non-null if we should use lifetime annotations.
2547     llvm::Value *SizeForLifetimeMarkers;
2548 
2549     /// Address with original alloca instruction. Invalid if the variable was
2550     /// emitted as a global constant.
2551     Address AllocaAddr;
2552 
2553     struct Invalid {};
2554     AutoVarEmission(Invalid)
2555         : Variable(nullptr), Addr(Address::invalid()),
2556           AllocaAddr(Address::invalid()) {}
2557 
2558     AutoVarEmission(const VarDecl &variable)
2559         : Variable(&variable), Addr(Address::invalid()), NRVOFlag(nullptr),
2560           IsByRef(false), IsConstantAggregate(false),
2561           SizeForLifetimeMarkers(nullptr), AllocaAddr(Address::invalid()) {}
2562 
2563     bool wasEmittedAsGlobal() const { return !Addr.isValid(); }
2564 
2565   public:
2566     static AutoVarEmission invalid() { return AutoVarEmission(Invalid()); }
2567 
2568     bool useLifetimeMarkers() const {
2569       return SizeForLifetimeMarkers != nullptr;
2570     }
2571     llvm::Value *getSizeForLifetimeMarkers() const {
2572       assert(useLifetimeMarkers());
2573       return SizeForLifetimeMarkers;
2574     }
2575 
2576     /// Returns the raw, allocated address, which is not necessarily
2577     /// the address of the object itself. It is casted to default
2578     /// address space for address space agnostic languages.
2579     Address getAllocatedAddress() const {
2580       return Addr;
2581     }
2582 
2583     /// Returns the address for the original alloca instruction.
2584     Address getOriginalAllocatedAddress() const { return AllocaAddr; }
2585 
2586     /// Returns the address of the object within this declaration.
2587     /// Note that this does not chase the forwarding pointer for
2588     /// __block decls.
2589     Address getObjectAddress(CodeGenFunction &CGF) const {
2590       if (!IsByRef) return Addr;
2591 
2592       return CGF.emitBlockByrefAddress(Addr, Variable, /*forward*/ false);
2593     }
2594   };
2595   AutoVarEmission EmitAutoVarAlloca(const VarDecl &var);
2596   void EmitAutoVarInit(const AutoVarEmission &emission);
2597   void EmitAutoVarCleanups(const AutoVarEmission &emission);
2598   void emitAutoVarTypeCleanup(const AutoVarEmission &emission,
2599                               QualType::DestructionKind dtorKind);
2600 
2601   /// Emits the alloca and debug information for the size expressions for each
2602   /// dimension of an array. It registers the association of its (1-dimensional)
2603   /// QualTypes and size expression's debug node, so that CGDebugInfo can
2604   /// reference this node when creating the DISubrange object to describe the
2605   /// array types.
2606   void EmitAndRegisterVariableArrayDimensions(CGDebugInfo *DI,
2607                                               const VarDecl &D,
2608                                               bool EmitDebugInfo);
2609 
2610   void EmitStaticVarDecl(const VarDecl &D,
2611                          llvm::GlobalValue::LinkageTypes Linkage);
2612 
2613   class ParamValue {
2614     llvm::Value *Value;
2615     unsigned Alignment;
2616     ParamValue(llvm::Value *V, unsigned A) : Value(V), Alignment(A) {}
2617   public:
2618     static ParamValue forDirect(llvm::Value *value) {
2619       return ParamValue(value, 0);
2620     }
2621     static ParamValue forIndirect(Address addr) {
2622       assert(!addr.getAlignment().isZero());
2623       return ParamValue(addr.getPointer(), addr.getAlignment().getQuantity());
2624     }
2625 
2626     bool isIndirect() const { return Alignment != 0; }
2627     llvm::Value *getAnyValue() const { return Value; }
2628 
2629     llvm::Value *getDirectValue() const {
2630       assert(!isIndirect());
2631       return Value;
2632     }
2633 
2634     Address getIndirectAddress() const {
2635       assert(isIndirect());
2636       return Address(Value, CharUnits::fromQuantity(Alignment));
2637     }
2638   };
2639 
2640   /// EmitParmDecl - Emit a ParmVarDecl or an ImplicitParamDecl.
2641   void EmitParmDecl(const VarDecl &D, ParamValue Arg, unsigned ArgNo);
2642 
2643   /// protectFromPeepholes - Protect a value that we're intending to
2644   /// store to the side, but which will probably be used later, from
2645   /// aggressive peepholing optimizations that might delete it.
2646   ///
2647   /// Pass the result to unprotectFromPeepholes to declare that
2648   /// protection is no longer required.
2649   ///
2650   /// There's no particular reason why this shouldn't apply to
2651   /// l-values, it's just that no existing peepholes work on pointers.
2652   PeepholeProtection protectFromPeepholes(RValue rvalue);
2653   void unprotectFromPeepholes(PeepholeProtection protection);
2654 
2655   void EmitAlignmentAssumption(llvm::Value *PtrValue, llvm::Value *Alignment,
2656                                llvm::Value *OffsetValue = nullptr) {
2657     Builder.CreateAlignmentAssumption(CGM.getDataLayout(), PtrValue, Alignment,
2658                                       OffsetValue);
2659   }
2660 
2661   //===--------------------------------------------------------------------===//
2662   //                             Statement Emission
2663   //===--------------------------------------------------------------------===//
2664 
2665   /// EmitStopPoint - Emit a debug stoppoint if we are emitting debug info.
2666   void EmitStopPoint(const Stmt *S);
2667 
2668   /// EmitStmt - Emit the code for the statement \arg S. It is legal to call
2669   /// this function even if there is no current insertion point.
2670   ///
2671   /// This function may clear the current insertion point; callers should use
2672   /// EnsureInsertPoint if they wish to subsequently generate code without first
2673   /// calling EmitBlock, EmitBranch, or EmitStmt.
2674   void EmitStmt(const Stmt *S, ArrayRef<const Attr *> Attrs = None);
2675 
2676   /// EmitSimpleStmt - Try to emit a "simple" statement which does not
2677   /// necessarily require an insertion point or debug information; typically
2678   /// because the statement amounts to a jump or a container of other
2679   /// statements.
2680   ///
2681   /// \return True if the statement was handled.
2682   bool EmitSimpleStmt(const Stmt *S);
2683 
2684   Address EmitCompoundStmt(const CompoundStmt &S, bool GetLast = false,
2685                            AggValueSlot AVS = AggValueSlot::ignored());
2686   Address EmitCompoundStmtWithoutScope(const CompoundStmt &S,
2687                                        bool GetLast = false,
2688                                        AggValueSlot AVS =
2689                                                 AggValueSlot::ignored());
2690 
2691   /// EmitLabel - Emit the block for the given label. It is legal to call this
2692   /// function even if there is no current insertion point.
2693   void EmitLabel(const LabelDecl *D); // helper for EmitLabelStmt.
2694 
2695   void EmitLabelStmt(const LabelStmt &S);
2696   void EmitAttributedStmt(const AttributedStmt &S);
2697   void EmitGotoStmt(const GotoStmt &S);
2698   void EmitIndirectGotoStmt(const IndirectGotoStmt &S);
2699   void EmitIfStmt(const IfStmt &S);
2700 
2701   void EmitWhileStmt(const WhileStmt &S,
2702                      ArrayRef<const Attr *> Attrs = None);
2703   void EmitDoStmt(const DoStmt &S, ArrayRef<const Attr *> Attrs = None);
2704   void EmitForStmt(const ForStmt &S,
2705                    ArrayRef<const Attr *> Attrs = None);
2706   void EmitReturnStmt(const ReturnStmt &S);
2707   void EmitDeclStmt(const DeclStmt &S);
2708   void EmitBreakStmt(const BreakStmt &S);
2709   void EmitContinueStmt(const ContinueStmt &S);
2710   void EmitSwitchStmt(const SwitchStmt &S);
2711   void EmitDefaultStmt(const DefaultStmt &S);
2712   void EmitCaseStmt(const CaseStmt &S);
2713   void EmitCaseStmtRange(const CaseStmt &S);
2714   void EmitAsmStmt(const AsmStmt &S);
2715 
2716   void EmitObjCForCollectionStmt(const ObjCForCollectionStmt &S);
2717   void EmitObjCAtTryStmt(const ObjCAtTryStmt &S);
2718   void EmitObjCAtThrowStmt(const ObjCAtThrowStmt &S);
2719   void EmitObjCAtSynchronizedStmt(const ObjCAtSynchronizedStmt &S);
2720   void EmitObjCAutoreleasePoolStmt(const ObjCAutoreleasePoolStmt &S);
2721 
2722   void EmitCoroutineBody(const CoroutineBodyStmt &S);
2723   void EmitCoreturnStmt(const CoreturnStmt &S);
2724   RValue EmitCoawaitExpr(const CoawaitExpr &E,
2725                          AggValueSlot aggSlot = AggValueSlot::ignored(),
2726                          bool ignoreResult = false);
2727   LValue EmitCoawaitLValue(const CoawaitExpr *E);
2728   RValue EmitCoyieldExpr(const CoyieldExpr &E,
2729                          AggValueSlot aggSlot = AggValueSlot::ignored(),
2730                          bool ignoreResult = false);
2731   LValue EmitCoyieldLValue(const CoyieldExpr *E);
2732   RValue EmitCoroutineIntrinsic(const CallExpr *E, unsigned int IID);
2733 
2734   void EnterCXXTryStmt(const CXXTryStmt &S, bool IsFnTryBlock = false);
2735   void ExitCXXTryStmt(const CXXTryStmt &S, bool IsFnTryBlock = false);
2736 
2737   void EmitCXXTryStmt(const CXXTryStmt &S);
2738   void EmitSEHTryStmt(const SEHTryStmt &S);
2739   void EmitSEHLeaveStmt(const SEHLeaveStmt &S);
2740   void EnterSEHTryStmt(const SEHTryStmt &S);
2741   void ExitSEHTryStmt(const SEHTryStmt &S);
2742 
2743   void startOutlinedSEHHelper(CodeGenFunction &ParentCGF, bool IsFilter,
2744                               const Stmt *OutlinedStmt);
2745 
2746   llvm::Function *GenerateSEHFilterFunction(CodeGenFunction &ParentCGF,
2747                                             const SEHExceptStmt &Except);
2748 
2749   llvm::Function *GenerateSEHFinallyFunction(CodeGenFunction &ParentCGF,
2750                                              const SEHFinallyStmt &Finally);
2751 
2752   void EmitSEHExceptionCodeSave(CodeGenFunction &ParentCGF,
2753                                 llvm::Value *ParentFP,
2754                                 llvm::Value *EntryEBP);
2755   llvm::Value *EmitSEHExceptionCode();
2756   llvm::Value *EmitSEHExceptionInfo();
2757   llvm::Value *EmitSEHAbnormalTermination();
2758 
2759   /// Emit simple code for OpenMP directives in Simd-only mode.
2760   void EmitSimpleOMPExecutableDirective(const OMPExecutableDirective &D);
2761 
2762   /// Scan the outlined statement for captures from the parent function. For
2763   /// each capture, mark the capture as escaped and emit a call to
2764   /// llvm.localrecover. Insert the localrecover result into the LocalDeclMap.
2765   void EmitCapturedLocals(CodeGenFunction &ParentCGF, const Stmt *OutlinedStmt,
2766                           bool IsFilter);
2767 
2768   /// Recovers the address of a local in a parent function. ParentVar is the
2769   /// address of the variable used in the immediate parent function. It can
2770   /// either be an alloca or a call to llvm.localrecover if there are nested
2771   /// outlined functions. ParentFP is the frame pointer of the outermost parent
2772   /// frame.
2773   Address recoverAddrOfEscapedLocal(CodeGenFunction &ParentCGF,
2774                                     Address ParentVar,
2775                                     llvm::Value *ParentFP);
2776 
2777   void EmitCXXForRangeStmt(const CXXForRangeStmt &S,
2778                            ArrayRef<const Attr *> Attrs = None);
2779 
2780   /// Controls insertion of cancellation exit blocks in worksharing constructs.
2781   class OMPCancelStackRAII {
2782     CodeGenFunction &CGF;
2783 
2784   public:
2785     OMPCancelStackRAII(CodeGenFunction &CGF, OpenMPDirectiveKind Kind,
2786                        bool HasCancel)
2787         : CGF(CGF) {
2788       CGF.OMPCancelStack.enter(CGF, Kind, HasCancel);
2789     }
2790     ~OMPCancelStackRAII() { CGF.OMPCancelStack.exit(CGF); }
2791   };
2792 
2793   /// Returns calculated size of the specified type.
2794   llvm::Value *getTypeSize(QualType Ty);
2795   LValue InitCapturedStruct(const CapturedStmt &S);
2796   llvm::Function *EmitCapturedStmt(const CapturedStmt &S, CapturedRegionKind K);
2797   llvm::Function *GenerateCapturedStmtFunction(const CapturedStmt &S);
2798   Address GenerateCapturedStmtArgument(const CapturedStmt &S);
2799   llvm::Function *GenerateOpenMPCapturedStmtFunction(const CapturedStmt &S);
2800   void GenerateOpenMPCapturedVars(const CapturedStmt &S,
2801                                   SmallVectorImpl<llvm::Value *> &CapturedVars);
2802   void emitOMPSimpleStore(LValue LVal, RValue RVal, QualType RValTy,
2803                           SourceLocation Loc);
2804   /// Perform element by element copying of arrays with type \a
2805   /// OriginalType from \a SrcAddr to \a DestAddr using copying procedure
2806   /// generated by \a CopyGen.
2807   ///
2808   /// \param DestAddr Address of the destination array.
2809   /// \param SrcAddr Address of the source array.
2810   /// \param OriginalType Type of destination and source arrays.
2811   /// \param CopyGen Copying procedure that copies value of single array element
2812   /// to another single array element.
2813   void EmitOMPAggregateAssign(
2814       Address DestAddr, Address SrcAddr, QualType OriginalType,
2815       const llvm::function_ref<void(Address, Address)> CopyGen);
2816   /// Emit proper copying of data from one variable to another.
2817   ///
2818   /// \param OriginalType Original type of the copied variables.
2819   /// \param DestAddr Destination address.
2820   /// \param SrcAddr Source address.
2821   /// \param DestVD Destination variable used in \a CopyExpr (for arrays, has
2822   /// type of the base array element).
2823   /// \param SrcVD Source variable used in \a CopyExpr (for arrays, has type of
2824   /// the base array element).
2825   /// \param Copy Actual copygin expression for copying data from \a SrcVD to \a
2826   /// DestVD.
2827   void EmitOMPCopy(QualType OriginalType,
2828                    Address DestAddr, Address SrcAddr,
2829                    const VarDecl *DestVD, const VarDecl *SrcVD,
2830                    const Expr *Copy);
2831   /// Emit atomic update code for constructs: \a X = \a X \a BO \a E or
2832   /// \a X = \a E \a BO \a E.
2833   ///
2834   /// \param X Value to be updated.
2835   /// \param E Update value.
2836   /// \param BO Binary operation for update operation.
2837   /// \param IsXLHSInRHSPart true if \a X is LHS in RHS part of the update
2838   /// expression, false otherwise.
2839   /// \param AO Atomic ordering of the generated atomic instructions.
2840   /// \param CommonGen Code generator for complex expressions that cannot be
2841   /// expressed through atomicrmw instruction.
2842   /// \returns <true, OldAtomicValue> if simple 'atomicrmw' instruction was
2843   /// generated, <false, RValue::get(nullptr)> otherwise.
2844   std::pair<bool, RValue> EmitOMPAtomicSimpleUpdateExpr(
2845       LValue X, RValue E, BinaryOperatorKind BO, bool IsXLHSInRHSPart,
2846       llvm::AtomicOrdering AO, SourceLocation Loc,
2847       const llvm::function_ref<RValue(RValue)> CommonGen);
2848   bool EmitOMPFirstprivateClause(const OMPExecutableDirective &D,
2849                                  OMPPrivateScope &PrivateScope);
2850   void EmitOMPPrivateClause(const OMPExecutableDirective &D,
2851                             OMPPrivateScope &PrivateScope);
2852   void EmitOMPUseDevicePtrClause(
2853       const OMPClause &C, OMPPrivateScope &PrivateScope,
2854       const llvm::DenseMap<const ValueDecl *, Address> &CaptureDeviceAddrMap);
2855   /// Emit code for copyin clause in \a D directive. The next code is
2856   /// generated at the start of outlined functions for directives:
2857   /// \code
2858   /// threadprivate_var1 = master_threadprivate_var1;
2859   /// operator=(threadprivate_var2, master_threadprivate_var2);
2860   /// ...
2861   /// __kmpc_barrier(&loc, global_tid);
2862   /// \endcode
2863   ///
2864   /// \param D OpenMP directive possibly with 'copyin' clause(s).
2865   /// \returns true if at least one copyin variable is found, false otherwise.
2866   bool EmitOMPCopyinClause(const OMPExecutableDirective &D);
2867   /// Emit initial code for lastprivate variables. If some variable is
2868   /// not also firstprivate, then the default initialization is used. Otherwise
2869   /// initialization of this variable is performed by EmitOMPFirstprivateClause
2870   /// method.
2871   ///
2872   /// \param D Directive that may have 'lastprivate' directives.
2873   /// \param PrivateScope Private scope for capturing lastprivate variables for
2874   /// proper codegen in internal captured statement.
2875   ///
2876   /// \returns true if there is at least one lastprivate variable, false
2877   /// otherwise.
2878   bool EmitOMPLastprivateClauseInit(const OMPExecutableDirective &D,
2879                                     OMPPrivateScope &PrivateScope);
2880   /// Emit final copying of lastprivate values to original variables at
2881   /// the end of the worksharing or simd directive.
2882   ///
2883   /// \param D Directive that has at least one 'lastprivate' directives.
2884   /// \param IsLastIterCond Boolean condition that must be set to 'i1 true' if
2885   /// it is the last iteration of the loop code in associated directive, or to
2886   /// 'i1 false' otherwise. If this item is nullptr, no final check is required.
2887   void EmitOMPLastprivateClauseFinal(const OMPExecutableDirective &D,
2888                                      bool NoFinals,
2889                                      llvm::Value *IsLastIterCond = nullptr);
2890   /// Emit initial code for linear clauses.
2891   void EmitOMPLinearClause(const OMPLoopDirective &D,
2892                            CodeGenFunction::OMPPrivateScope &PrivateScope);
2893   /// Emit final code for linear clauses.
2894   /// \param CondGen Optional conditional code for final part of codegen for
2895   /// linear clause.
2896   void EmitOMPLinearClauseFinal(
2897       const OMPLoopDirective &D,
2898       const llvm::function_ref<llvm::Value *(CodeGenFunction &)> CondGen);
2899   /// Emit initial code for reduction variables. Creates reduction copies
2900   /// and initializes them with the values according to OpenMP standard.
2901   ///
2902   /// \param D Directive (possibly) with the 'reduction' clause.
2903   /// \param PrivateScope Private scope for capturing reduction variables for
2904   /// proper codegen in internal captured statement.
2905   ///
2906   void EmitOMPReductionClauseInit(const OMPExecutableDirective &D,
2907                                   OMPPrivateScope &PrivateScope);
2908   /// Emit final update of reduction values to original variables at
2909   /// the end of the directive.
2910   ///
2911   /// \param D Directive that has at least one 'reduction' directives.
2912   /// \param ReductionKind The kind of reduction to perform.
2913   void EmitOMPReductionClauseFinal(const OMPExecutableDirective &D,
2914                                    const OpenMPDirectiveKind ReductionKind);
2915   /// Emit initial code for linear variables. Creates private copies
2916   /// and initializes them with the values according to OpenMP standard.
2917   ///
2918   /// \param D Directive (possibly) with the 'linear' clause.
2919   /// \return true if at least one linear variable is found that should be
2920   /// initialized with the value of the original variable, false otherwise.
2921   bool EmitOMPLinearClauseInit(const OMPLoopDirective &D);
2922 
2923   typedef const llvm::function_ref<void(CodeGenFunction & /*CGF*/,
2924                                         llvm::Value * /*OutlinedFn*/,
2925                                         const OMPTaskDataTy & /*Data*/)>
2926       TaskGenTy;
2927   void EmitOMPTaskBasedDirective(const OMPExecutableDirective &S,
2928                                  const OpenMPDirectiveKind CapturedRegion,
2929                                  const RegionCodeGenTy &BodyGen,
2930                                  const TaskGenTy &TaskGen, OMPTaskDataTy &Data);
2931   struct OMPTargetDataInfo {
2932     Address BasePointersArray = Address::invalid();
2933     Address PointersArray = Address::invalid();
2934     Address SizesArray = Address::invalid();
2935     unsigned NumberOfTargetItems = 0;
2936     explicit OMPTargetDataInfo() = default;
2937     OMPTargetDataInfo(Address BasePointersArray, Address PointersArray,
2938                       Address SizesArray, unsigned NumberOfTargetItems)
2939         : BasePointersArray(BasePointersArray), PointersArray(PointersArray),
2940           SizesArray(SizesArray), NumberOfTargetItems(NumberOfTargetItems) {}
2941   };
2942   void EmitOMPTargetTaskBasedDirective(const OMPExecutableDirective &S,
2943                                        const RegionCodeGenTy &BodyGen,
2944                                        OMPTargetDataInfo &InputInfo);
2945 
2946   void EmitOMPParallelDirective(const OMPParallelDirective &S);
2947   void EmitOMPSimdDirective(const OMPSimdDirective &S);
2948   void EmitOMPForDirective(const OMPForDirective &S);
2949   void EmitOMPForSimdDirective(const OMPForSimdDirective &S);
2950   void EmitOMPSectionsDirective(const OMPSectionsDirective &S);
2951   void EmitOMPSectionDirective(const OMPSectionDirective &S);
2952   void EmitOMPSingleDirective(const OMPSingleDirective &S);
2953   void EmitOMPMasterDirective(const OMPMasterDirective &S);
2954   void EmitOMPCriticalDirective(const OMPCriticalDirective &S);
2955   void EmitOMPParallelForDirective(const OMPParallelForDirective &S);
2956   void EmitOMPParallelForSimdDirective(const OMPParallelForSimdDirective &S);
2957   void EmitOMPParallelSectionsDirective(const OMPParallelSectionsDirective &S);
2958   void EmitOMPTaskDirective(const OMPTaskDirective &S);
2959   void EmitOMPTaskyieldDirective(const OMPTaskyieldDirective &S);
2960   void EmitOMPBarrierDirective(const OMPBarrierDirective &S);
2961   void EmitOMPTaskwaitDirective(const OMPTaskwaitDirective &S);
2962   void EmitOMPTaskgroupDirective(const OMPTaskgroupDirective &S);
2963   void EmitOMPFlushDirective(const OMPFlushDirective &S);
2964   void EmitOMPOrderedDirective(const OMPOrderedDirective &S);
2965   void EmitOMPAtomicDirective(const OMPAtomicDirective &S);
2966   void EmitOMPTargetDirective(const OMPTargetDirective &S);
2967   void EmitOMPTargetDataDirective(const OMPTargetDataDirective &S);
2968   void EmitOMPTargetEnterDataDirective(const OMPTargetEnterDataDirective &S);
2969   void EmitOMPTargetExitDataDirective(const OMPTargetExitDataDirective &S);
2970   void EmitOMPTargetUpdateDirective(const OMPTargetUpdateDirective &S);
2971   void EmitOMPTargetParallelDirective(const OMPTargetParallelDirective &S);
2972   void
2973   EmitOMPTargetParallelForDirective(const OMPTargetParallelForDirective &S);
2974   void EmitOMPTeamsDirective(const OMPTeamsDirective &S);
2975   void
2976   EmitOMPCancellationPointDirective(const OMPCancellationPointDirective &S);
2977   void EmitOMPCancelDirective(const OMPCancelDirective &S);
2978   void EmitOMPTaskLoopBasedDirective(const OMPLoopDirective &S);
2979   void EmitOMPTaskLoopDirective(const OMPTaskLoopDirective &S);
2980   void EmitOMPTaskLoopSimdDirective(const OMPTaskLoopSimdDirective &S);
2981   void EmitOMPDistributeDirective(const OMPDistributeDirective &S);
2982   void EmitOMPDistributeParallelForDirective(
2983       const OMPDistributeParallelForDirective &S);
2984   void EmitOMPDistributeParallelForSimdDirective(
2985       const OMPDistributeParallelForSimdDirective &S);
2986   void EmitOMPDistributeSimdDirective(const OMPDistributeSimdDirective &S);
2987   void EmitOMPTargetParallelForSimdDirective(
2988       const OMPTargetParallelForSimdDirective &S);
2989   void EmitOMPTargetSimdDirective(const OMPTargetSimdDirective &S);
2990   void EmitOMPTeamsDistributeDirective(const OMPTeamsDistributeDirective &S);
2991   void
2992   EmitOMPTeamsDistributeSimdDirective(const OMPTeamsDistributeSimdDirective &S);
2993   void EmitOMPTeamsDistributeParallelForSimdDirective(
2994       const OMPTeamsDistributeParallelForSimdDirective &S);
2995   void EmitOMPTeamsDistributeParallelForDirective(
2996       const OMPTeamsDistributeParallelForDirective &S);
2997   void EmitOMPTargetTeamsDirective(const OMPTargetTeamsDirective &S);
2998   void EmitOMPTargetTeamsDistributeDirective(
2999       const OMPTargetTeamsDistributeDirective &S);
3000   void EmitOMPTargetTeamsDistributeParallelForDirective(
3001       const OMPTargetTeamsDistributeParallelForDirective &S);
3002   void EmitOMPTargetTeamsDistributeParallelForSimdDirective(
3003       const OMPTargetTeamsDistributeParallelForSimdDirective &S);
3004   void EmitOMPTargetTeamsDistributeSimdDirective(
3005       const OMPTargetTeamsDistributeSimdDirective &S);
3006 
3007   /// Emit device code for the target directive.
3008   static void EmitOMPTargetDeviceFunction(CodeGenModule &CGM,
3009                                           StringRef ParentName,
3010                                           const OMPTargetDirective &S);
3011   static void
3012   EmitOMPTargetParallelDeviceFunction(CodeGenModule &CGM, StringRef ParentName,
3013                                       const OMPTargetParallelDirective &S);
3014   /// Emit device code for the target parallel for directive.
3015   static void EmitOMPTargetParallelForDeviceFunction(
3016       CodeGenModule &CGM, StringRef ParentName,
3017       const OMPTargetParallelForDirective &S);
3018   /// Emit device code for the target parallel for simd directive.
3019   static void EmitOMPTargetParallelForSimdDeviceFunction(
3020       CodeGenModule &CGM, StringRef ParentName,
3021       const OMPTargetParallelForSimdDirective &S);
3022   /// Emit device code for the target teams directive.
3023   static void
3024   EmitOMPTargetTeamsDeviceFunction(CodeGenModule &CGM, StringRef ParentName,
3025                                    const OMPTargetTeamsDirective &S);
3026   /// Emit device code for the target teams distribute directive.
3027   static void EmitOMPTargetTeamsDistributeDeviceFunction(
3028       CodeGenModule &CGM, StringRef ParentName,
3029       const OMPTargetTeamsDistributeDirective &S);
3030   /// Emit device code for the target teams distribute simd directive.
3031   static void EmitOMPTargetTeamsDistributeSimdDeviceFunction(
3032       CodeGenModule &CGM, StringRef ParentName,
3033       const OMPTargetTeamsDistributeSimdDirective &S);
3034   /// Emit device code for the target simd directive.
3035   static void EmitOMPTargetSimdDeviceFunction(CodeGenModule &CGM,
3036                                               StringRef ParentName,
3037                                               const OMPTargetSimdDirective &S);
3038   /// Emit device code for the target teams distribute parallel for simd
3039   /// directive.
3040   static void EmitOMPTargetTeamsDistributeParallelForSimdDeviceFunction(
3041       CodeGenModule &CGM, StringRef ParentName,
3042       const OMPTargetTeamsDistributeParallelForSimdDirective &S);
3043 
3044   static void EmitOMPTargetTeamsDistributeParallelForDeviceFunction(
3045       CodeGenModule &CGM, StringRef ParentName,
3046       const OMPTargetTeamsDistributeParallelForDirective &S);
3047   /// Emit inner loop of the worksharing/simd construct.
3048   ///
3049   /// \param S Directive, for which the inner loop must be emitted.
3050   /// \param RequiresCleanup true, if directive has some associated private
3051   /// variables.
3052   /// \param LoopCond Bollean condition for loop continuation.
3053   /// \param IncExpr Increment expression for loop control variable.
3054   /// \param BodyGen Generator for the inner body of the inner loop.
3055   /// \param PostIncGen Genrator for post-increment code (required for ordered
3056   /// loop directvies).
3057   void EmitOMPInnerLoop(
3058       const Stmt &S, bool RequiresCleanup, const Expr *LoopCond,
3059       const Expr *IncExpr,
3060       const llvm::function_ref<void(CodeGenFunction &)> BodyGen,
3061       const llvm::function_ref<void(CodeGenFunction &)> PostIncGen);
3062 
3063   JumpDest getOMPCancelDestination(OpenMPDirectiveKind Kind);
3064   /// Emit initial code for loop counters of loop-based directives.
3065   void EmitOMPPrivateLoopCounters(const OMPLoopDirective &S,
3066                                   OMPPrivateScope &LoopScope);
3067 
3068   /// Helper for the OpenMP loop directives.
3069   void EmitOMPLoopBody(const OMPLoopDirective &D, JumpDest LoopExit);
3070 
3071   /// Emit code for the worksharing loop-based directive.
3072   /// \return true, if this construct has any lastprivate clause, false -
3073   /// otherwise.
3074   bool EmitOMPWorksharingLoop(const OMPLoopDirective &S, Expr *EUB,
3075                               const CodeGenLoopBoundsTy &CodeGenLoopBounds,
3076                               const CodeGenDispatchBoundsTy &CGDispatchBounds);
3077 
3078   /// Emit code for the distribute loop-based directive.
3079   void EmitOMPDistributeLoop(const OMPLoopDirective &S,
3080                              const CodeGenLoopTy &CodeGenLoop, Expr *IncExpr);
3081 
3082   /// Helpers for the OpenMP loop directives.
3083   void EmitOMPSimdInit(const OMPLoopDirective &D, bool IsMonotonic = false);
3084   void EmitOMPSimdFinal(
3085       const OMPLoopDirective &D,
3086       const llvm::function_ref<llvm::Value *(CodeGenFunction &)> CondGen);
3087 
3088   /// Emits the lvalue for the expression with possibly captured variable.
3089   LValue EmitOMPSharedLValue(const Expr *E);
3090 
3091 private:
3092   /// Helpers for blocks.
3093   llvm::Value *EmitBlockLiteral(const CGBlockInfo &Info);
3094 
3095   /// struct with the values to be passed to the OpenMP loop-related functions
3096   struct OMPLoopArguments {
3097     /// loop lower bound
3098     Address LB = Address::invalid();
3099     /// loop upper bound
3100     Address UB = Address::invalid();
3101     /// loop stride
3102     Address ST = Address::invalid();
3103     /// isLastIteration argument for runtime functions
3104     Address IL = Address::invalid();
3105     /// Chunk value generated by sema
3106     llvm::Value *Chunk = nullptr;
3107     /// EnsureUpperBound
3108     Expr *EUB = nullptr;
3109     /// IncrementExpression
3110     Expr *IncExpr = nullptr;
3111     /// Loop initialization
3112     Expr *Init = nullptr;
3113     /// Loop exit condition
3114     Expr *Cond = nullptr;
3115     /// Update of LB after a whole chunk has been executed
3116     Expr *NextLB = nullptr;
3117     /// Update of UB after a whole chunk has been executed
3118     Expr *NextUB = nullptr;
3119     OMPLoopArguments() = default;
3120     OMPLoopArguments(Address LB, Address UB, Address ST, Address IL,
3121                      llvm::Value *Chunk = nullptr, Expr *EUB = nullptr,
3122                      Expr *IncExpr = nullptr, Expr *Init = nullptr,
3123                      Expr *Cond = nullptr, Expr *NextLB = nullptr,
3124                      Expr *NextUB = nullptr)
3125         : LB(LB), UB(UB), ST(ST), IL(IL), Chunk(Chunk), EUB(EUB),
3126           IncExpr(IncExpr), Init(Init), Cond(Cond), NextLB(NextLB),
3127           NextUB(NextUB) {}
3128   };
3129   void EmitOMPOuterLoop(bool DynamicOrOrdered, bool IsMonotonic,
3130                         const OMPLoopDirective &S, OMPPrivateScope &LoopScope,
3131                         const OMPLoopArguments &LoopArgs,
3132                         const CodeGenLoopTy &CodeGenLoop,
3133                         const CodeGenOrderedTy &CodeGenOrdered);
3134   void EmitOMPForOuterLoop(const OpenMPScheduleTy &ScheduleKind,
3135                            bool IsMonotonic, const OMPLoopDirective &S,
3136                            OMPPrivateScope &LoopScope, bool Ordered,
3137                            const OMPLoopArguments &LoopArgs,
3138                            const CodeGenDispatchBoundsTy &CGDispatchBounds);
3139   void EmitOMPDistributeOuterLoop(OpenMPDistScheduleClauseKind ScheduleKind,
3140                                   const OMPLoopDirective &S,
3141                                   OMPPrivateScope &LoopScope,
3142                                   const OMPLoopArguments &LoopArgs,
3143                                   const CodeGenLoopTy &CodeGenLoopContent);
3144   /// Emit code for sections directive.
3145   void EmitSections(const OMPExecutableDirective &S);
3146 
3147 public:
3148 
3149   //===--------------------------------------------------------------------===//
3150   //                         LValue Expression Emission
3151   //===--------------------------------------------------------------------===//
3152 
3153   /// GetUndefRValue - Get an appropriate 'undef' rvalue for the given type.
3154   RValue GetUndefRValue(QualType Ty);
3155 
3156   /// EmitUnsupportedRValue - Emit a dummy r-value using the type of E
3157   /// and issue an ErrorUnsupported style diagnostic (using the
3158   /// provided Name).
3159   RValue EmitUnsupportedRValue(const Expr *E,
3160                                const char *Name);
3161 
3162   /// EmitUnsupportedLValue - Emit a dummy l-value using the type of E and issue
3163   /// an ErrorUnsupported style diagnostic (using the provided Name).
3164   LValue EmitUnsupportedLValue(const Expr *E,
3165                                const char *Name);
3166 
3167   /// EmitLValue - Emit code to compute a designator that specifies the location
3168   /// of the expression.
3169   ///
3170   /// This can return one of two things: a simple address or a bitfield
3171   /// reference.  In either case, the LLVM Value* in the LValue structure is
3172   /// guaranteed to be an LLVM pointer type.
3173   ///
3174   /// If this returns a bitfield reference, nothing about the pointee type of
3175   /// the LLVM value is known: For example, it may not be a pointer to an
3176   /// integer.
3177   ///
3178   /// If this returns a normal address, and if the lvalue's C type is fixed
3179   /// size, this method guarantees that the returned pointer type will point to
3180   /// an LLVM type of the same size of the lvalue's type.  If the lvalue has a
3181   /// variable length type, this is not possible.
3182   ///
3183   LValue EmitLValue(const Expr *E);
3184 
3185   /// Same as EmitLValue but additionally we generate checking code to
3186   /// guard against undefined behavior.  This is only suitable when we know
3187   /// that the address will be used to access the object.
3188   LValue EmitCheckedLValue(const Expr *E, TypeCheckKind TCK);
3189 
3190   RValue convertTempToRValue(Address addr, QualType type,
3191                              SourceLocation Loc);
3192 
3193   void EmitAtomicInit(Expr *E, LValue lvalue);
3194 
3195   bool LValueIsSuitableForInlineAtomic(LValue Src);
3196 
3197   RValue EmitAtomicLoad(LValue LV, SourceLocation SL,
3198                         AggValueSlot Slot = AggValueSlot::ignored());
3199 
3200   RValue EmitAtomicLoad(LValue lvalue, SourceLocation loc,
3201                         llvm::AtomicOrdering AO, bool IsVolatile = false,
3202                         AggValueSlot slot = AggValueSlot::ignored());
3203 
3204   void EmitAtomicStore(RValue rvalue, LValue lvalue, bool isInit);
3205 
3206   void EmitAtomicStore(RValue rvalue, LValue lvalue, llvm::AtomicOrdering AO,
3207                        bool IsVolatile, bool isInit);
3208 
3209   std::pair<RValue, llvm::Value *> EmitAtomicCompareExchange(
3210       LValue Obj, RValue Expected, RValue Desired, SourceLocation Loc,
3211       llvm::AtomicOrdering Success =
3212           llvm::AtomicOrdering::SequentiallyConsistent,
3213       llvm::AtomicOrdering Failure =
3214           llvm::AtomicOrdering::SequentiallyConsistent,
3215       bool IsWeak = false, AggValueSlot Slot = AggValueSlot::ignored());
3216 
3217   void EmitAtomicUpdate(LValue LVal, llvm::AtomicOrdering AO,
3218                         const llvm::function_ref<RValue(RValue)> &UpdateOp,
3219                         bool IsVolatile);
3220 
3221   /// EmitToMemory - Change a scalar value from its value
3222   /// representation to its in-memory representation.
3223   llvm::Value *EmitToMemory(llvm::Value *Value, QualType Ty);
3224 
3225   /// EmitFromMemory - Change a scalar value from its memory
3226   /// representation to its value representation.
3227   llvm::Value *EmitFromMemory(llvm::Value *Value, QualType Ty);
3228 
3229   /// Check if the scalar \p Value is within the valid range for the given
3230   /// type \p Ty.
3231   ///
3232   /// Returns true if a check is needed (even if the range is unknown).
3233   bool EmitScalarRangeCheck(llvm::Value *Value, QualType Ty,
3234                             SourceLocation Loc);
3235 
3236   /// EmitLoadOfScalar - Load a scalar value from an address, taking
3237   /// care to appropriately convert from the memory representation to
3238   /// the LLVM value representation.
3239   llvm::Value *EmitLoadOfScalar(Address Addr, bool Volatile, QualType Ty,
3240                                 SourceLocation Loc,
3241                                 AlignmentSource Source = AlignmentSource::Type,
3242                                 bool isNontemporal = false) {
3243     return EmitLoadOfScalar(Addr, Volatile, Ty, Loc, LValueBaseInfo(Source),
3244                             CGM.getTBAAAccessInfo(Ty), isNontemporal);
3245   }
3246 
3247   llvm::Value *EmitLoadOfScalar(Address Addr, bool Volatile, QualType Ty,
3248                                 SourceLocation Loc, LValueBaseInfo BaseInfo,
3249                                 TBAAAccessInfo TBAAInfo,
3250                                 bool isNontemporal = false);
3251 
3252   /// EmitLoadOfScalar - Load a scalar value from an address, taking
3253   /// care to appropriately convert from the memory representation to
3254   /// the LLVM value representation.  The l-value must be a simple
3255   /// l-value.
3256   llvm::Value *EmitLoadOfScalar(LValue lvalue, SourceLocation Loc);
3257 
3258   /// EmitStoreOfScalar - Store a scalar value to an address, taking
3259   /// care to appropriately convert from the memory representation to
3260   /// the LLVM value representation.
3261   void EmitStoreOfScalar(llvm::Value *Value, Address Addr,
3262                          bool Volatile, QualType Ty,
3263                          AlignmentSource Source = AlignmentSource::Type,
3264                          bool isInit = false, bool isNontemporal = false) {
3265     EmitStoreOfScalar(Value, Addr, Volatile, Ty, LValueBaseInfo(Source),
3266                       CGM.getTBAAAccessInfo(Ty), isInit, isNontemporal);
3267   }
3268 
3269   void EmitStoreOfScalar(llvm::Value *Value, Address Addr,
3270                          bool Volatile, QualType Ty,
3271                          LValueBaseInfo BaseInfo, TBAAAccessInfo TBAAInfo,
3272                          bool isInit = false, bool isNontemporal = false);
3273 
3274   /// EmitStoreOfScalar - Store a scalar value to an address, taking
3275   /// care to appropriately convert from the memory representation to
3276   /// the LLVM value representation.  The l-value must be a simple
3277   /// l-value.  The isInit flag indicates whether this is an initialization.
3278   /// If so, atomic qualifiers are ignored and the store is always non-atomic.
3279   void EmitStoreOfScalar(llvm::Value *value, LValue lvalue, bool isInit=false);
3280 
3281   /// EmitLoadOfLValue - Given an expression that represents a value lvalue,
3282   /// this method emits the address of the lvalue, then loads the result as an
3283   /// rvalue, returning the rvalue.
3284   RValue EmitLoadOfLValue(LValue V, SourceLocation Loc);
3285   RValue EmitLoadOfExtVectorElementLValue(LValue V);
3286   RValue EmitLoadOfBitfieldLValue(LValue LV, SourceLocation Loc);
3287   RValue EmitLoadOfGlobalRegLValue(LValue LV);
3288 
3289   /// EmitStoreThroughLValue - Store the specified rvalue into the specified
3290   /// lvalue, where both are guaranteed to the have the same type, and that type
3291   /// is 'Ty'.
3292   void EmitStoreThroughLValue(RValue Src, LValue Dst, bool isInit = false);
3293   void EmitStoreThroughExtVectorComponentLValue(RValue Src, LValue Dst);
3294   void EmitStoreThroughGlobalRegLValue(RValue Src, LValue Dst);
3295 
3296   /// EmitStoreThroughBitfieldLValue - Store Src into Dst with same constraints
3297   /// as EmitStoreThroughLValue.
3298   ///
3299   /// \param Result [out] - If non-null, this will be set to a Value* for the
3300   /// bit-field contents after the store, appropriate for use as the result of
3301   /// an assignment to the bit-field.
3302   void EmitStoreThroughBitfieldLValue(RValue Src, LValue Dst,
3303                                       llvm::Value **Result=nullptr);
3304 
3305   /// Emit an l-value for an assignment (simple or compound) of complex type.
3306   LValue EmitComplexAssignmentLValue(const BinaryOperator *E);
3307   LValue EmitComplexCompoundAssignmentLValue(const CompoundAssignOperator *E);
3308   LValue EmitScalarCompoundAssignWithComplex(const CompoundAssignOperator *E,
3309                                              llvm::Value *&Result);
3310 
3311   // Note: only available for agg return types
3312   LValue EmitBinaryOperatorLValue(const BinaryOperator *E);
3313   LValue EmitCompoundAssignmentLValue(const CompoundAssignOperator *E);
3314   // Note: only available for agg return types
3315   LValue EmitCallExprLValue(const CallExpr *E);
3316   // Note: only available for agg return types
3317   LValue EmitVAArgExprLValue(const VAArgExpr *E);
3318   LValue EmitDeclRefLValue(const DeclRefExpr *E);
3319   LValue EmitStringLiteralLValue(const StringLiteral *E);
3320   LValue EmitObjCEncodeExprLValue(const ObjCEncodeExpr *E);
3321   LValue EmitPredefinedLValue(const PredefinedExpr *E);
3322   LValue EmitUnaryOpLValue(const UnaryOperator *E);
3323   LValue EmitArraySubscriptExpr(const ArraySubscriptExpr *E,
3324                                 bool Accessed = false);
3325   LValue EmitOMPArraySectionExpr(const OMPArraySectionExpr *E,
3326                                  bool IsLowerBound = true);
3327   LValue EmitExtVectorElementExpr(const ExtVectorElementExpr *E);
3328   LValue EmitMemberExpr(const MemberExpr *E);
3329   LValue EmitObjCIsaExpr(const ObjCIsaExpr *E);
3330   LValue EmitCompoundLiteralLValue(const CompoundLiteralExpr *E);
3331   LValue EmitInitListLValue(const InitListExpr *E);
3332   LValue EmitConditionalOperatorLValue(const AbstractConditionalOperator *E);
3333   LValue EmitCastLValue(const CastExpr *E);
3334   LValue EmitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *E);
3335   LValue EmitOpaqueValueLValue(const OpaqueValueExpr *e);
3336 
3337   Address EmitExtVectorElementLValue(LValue V);
3338 
3339   RValue EmitRValueForField(LValue LV, const FieldDecl *FD, SourceLocation Loc);
3340 
3341   Address EmitArrayToPointerDecay(const Expr *Array,
3342                                   LValueBaseInfo *BaseInfo = nullptr,
3343                                   TBAAAccessInfo *TBAAInfo = nullptr);
3344 
3345   class ConstantEmission {
3346     llvm::PointerIntPair<llvm::Constant*, 1, bool> ValueAndIsReference;
3347     ConstantEmission(llvm::Constant *C, bool isReference)
3348       : ValueAndIsReference(C, isReference) {}
3349   public:
3350     ConstantEmission() {}
3351     static ConstantEmission forReference(llvm::Constant *C) {
3352       return ConstantEmission(C, true);
3353     }
3354     static ConstantEmission forValue(llvm::Constant *C) {
3355       return ConstantEmission(C, false);
3356     }
3357 
3358     explicit operator bool() const {
3359       return ValueAndIsReference.getOpaqueValue() != nullptr;
3360     }
3361 
3362     bool isReference() const { return ValueAndIsReference.getInt(); }
3363     LValue getReferenceLValue(CodeGenFunction &CGF, Expr *refExpr) const {
3364       assert(isReference());
3365       return CGF.MakeNaturalAlignAddrLValue(ValueAndIsReference.getPointer(),
3366                                             refExpr->getType());
3367     }
3368 
3369     llvm::Constant *getValue() const {
3370       assert(!isReference());
3371       return ValueAndIsReference.getPointer();
3372     }
3373   };
3374 
3375   ConstantEmission tryEmitAsConstant(DeclRefExpr *refExpr);
3376   ConstantEmission tryEmitAsConstant(const MemberExpr *ME);
3377 
3378   RValue EmitPseudoObjectRValue(const PseudoObjectExpr *e,
3379                                 AggValueSlot slot = AggValueSlot::ignored());
3380   LValue EmitPseudoObjectLValue(const PseudoObjectExpr *e);
3381 
3382   llvm::Value *EmitIvarOffset(const ObjCInterfaceDecl *Interface,
3383                               const ObjCIvarDecl *Ivar);
3384   LValue EmitLValueForField(LValue Base, const FieldDecl* Field);
3385   LValue EmitLValueForLambdaField(const FieldDecl *Field);
3386 
3387   /// EmitLValueForFieldInitialization - Like EmitLValueForField, except that
3388   /// if the Field is a reference, this will return the address of the reference
3389   /// and not the address of the value stored in the reference.
3390   LValue EmitLValueForFieldInitialization(LValue Base,
3391                                           const FieldDecl* Field);
3392 
3393   LValue EmitLValueForIvar(QualType ObjectTy,
3394                            llvm::Value* Base, const ObjCIvarDecl *Ivar,
3395                            unsigned CVRQualifiers);
3396 
3397   LValue EmitCXXConstructLValue(const CXXConstructExpr *E);
3398   LValue EmitCXXBindTemporaryLValue(const CXXBindTemporaryExpr *E);
3399   LValue EmitLambdaLValue(const LambdaExpr *E);
3400   LValue EmitCXXTypeidLValue(const CXXTypeidExpr *E);
3401   LValue EmitCXXUuidofLValue(const CXXUuidofExpr *E);
3402 
3403   LValue EmitObjCMessageExprLValue(const ObjCMessageExpr *E);
3404   LValue EmitObjCIvarRefLValue(const ObjCIvarRefExpr *E);
3405   LValue EmitStmtExprLValue(const StmtExpr *E);
3406   LValue EmitPointerToDataMemberBinaryExpr(const BinaryOperator *E);
3407   LValue EmitObjCSelectorLValue(const ObjCSelectorExpr *E);
3408   void   EmitDeclRefExprDbgValue(const DeclRefExpr *E, const APValue &Init);
3409 
3410   //===--------------------------------------------------------------------===//
3411   //                         Scalar Expression Emission
3412   //===--------------------------------------------------------------------===//
3413 
3414   /// EmitCall - Generate a call of the given function, expecting the given
3415   /// result type, and using the given argument list which specifies both the
3416   /// LLVM arguments and the types they were derived from.
3417   RValue EmitCall(const CGFunctionInfo &CallInfo, const CGCallee &Callee,
3418                   ReturnValueSlot ReturnValue, const CallArgList &Args,
3419                   llvm::Instruction **callOrInvoke, SourceLocation Loc);
3420   RValue EmitCall(const CGFunctionInfo &CallInfo, const CGCallee &Callee,
3421                   ReturnValueSlot ReturnValue, const CallArgList &Args,
3422                   llvm::Instruction **callOrInvoke = nullptr) {
3423     return EmitCall(CallInfo, Callee, ReturnValue, Args, callOrInvoke,
3424                     SourceLocation());
3425   }
3426   RValue EmitCall(QualType FnType, const CGCallee &Callee, const CallExpr *E,
3427                   ReturnValueSlot ReturnValue, llvm::Value *Chain = nullptr);
3428   RValue EmitCallExpr(const CallExpr *E,
3429                       ReturnValueSlot ReturnValue = ReturnValueSlot());
3430   RValue EmitSimpleCallExpr(const CallExpr *E, ReturnValueSlot ReturnValue);
3431   CGCallee EmitCallee(const Expr *E);
3432 
3433   void checkTargetFeatures(const CallExpr *E, const FunctionDecl *TargetDecl);
3434 
3435   llvm::CallInst *EmitRuntimeCall(llvm::Value *callee,
3436                                   const Twine &name = "");
3437   llvm::CallInst *EmitRuntimeCall(llvm::Value *callee,
3438                                   ArrayRef<llvm::Value*> args,
3439                                   const Twine &name = "");
3440   llvm::CallInst *EmitNounwindRuntimeCall(llvm::Value *callee,
3441                                           const Twine &name = "");
3442   llvm::CallInst *EmitNounwindRuntimeCall(llvm::Value *callee,
3443                                           ArrayRef<llvm::Value*> args,
3444                                           const Twine &name = "");
3445 
3446   SmallVector<llvm::OperandBundleDef, 1>
3447   getBundlesForFunclet(llvm::Value *Callee);
3448 
3449   llvm::CallSite EmitCallOrInvoke(llvm::Value *Callee,
3450                                   ArrayRef<llvm::Value *> Args,
3451                                   const Twine &Name = "");
3452   llvm::CallSite EmitRuntimeCallOrInvoke(llvm::Value *callee,
3453                                          ArrayRef<llvm::Value*> args,
3454                                          const Twine &name = "");
3455   llvm::CallSite EmitRuntimeCallOrInvoke(llvm::Value *callee,
3456                                          const Twine &name = "");
3457   void EmitNoreturnRuntimeCallOrInvoke(llvm::Value *callee,
3458                                        ArrayRef<llvm::Value*> args);
3459 
3460   CGCallee BuildAppleKextVirtualCall(const CXXMethodDecl *MD,
3461                                      NestedNameSpecifier *Qual,
3462                                      llvm::Type *Ty);
3463 
3464   CGCallee BuildAppleKextVirtualDestructorCall(const CXXDestructorDecl *DD,
3465                                                CXXDtorType Type,
3466                                                const CXXRecordDecl *RD);
3467 
3468   // These functions emit calls to the special functions of non-trivial C
3469   // structs.
3470   void defaultInitNonTrivialCStructVar(LValue Dst);
3471   void callCStructDefaultConstructor(LValue Dst);
3472   void callCStructDestructor(LValue Dst);
3473   void callCStructCopyConstructor(LValue Dst, LValue Src);
3474   void callCStructMoveConstructor(LValue Dst, LValue Src);
3475   void callCStructCopyAssignmentOperator(LValue Dst, LValue Src);
3476   void callCStructMoveAssignmentOperator(LValue Dst, LValue Src);
3477 
3478   RValue
3479   EmitCXXMemberOrOperatorCall(const CXXMethodDecl *Method,
3480                               const CGCallee &Callee,
3481                               ReturnValueSlot ReturnValue, llvm::Value *This,
3482                               llvm::Value *ImplicitParam,
3483                               QualType ImplicitParamTy, const CallExpr *E,
3484                               CallArgList *RtlArgs);
3485   RValue EmitCXXDestructorCall(const CXXDestructorDecl *DD,
3486                                const CGCallee &Callee,
3487                                llvm::Value *This, llvm::Value *ImplicitParam,
3488                                QualType ImplicitParamTy, const CallExpr *E,
3489                                StructorType Type);
3490   RValue EmitCXXMemberCallExpr(const CXXMemberCallExpr *E,
3491                                ReturnValueSlot ReturnValue);
3492   RValue EmitCXXMemberOrOperatorMemberCallExpr(const CallExpr *CE,
3493                                                const CXXMethodDecl *MD,
3494                                                ReturnValueSlot ReturnValue,
3495                                                bool HasQualifier,
3496                                                NestedNameSpecifier *Qualifier,
3497                                                bool IsArrow, const Expr *Base);
3498   // Compute the object pointer.
3499   Address EmitCXXMemberDataPointerAddress(const Expr *E, Address base,
3500                                           llvm::Value *memberPtr,
3501                                           const MemberPointerType *memberPtrType,
3502                                           LValueBaseInfo *BaseInfo = nullptr,
3503                                           TBAAAccessInfo *TBAAInfo = nullptr);
3504   RValue EmitCXXMemberPointerCallExpr(const CXXMemberCallExpr *E,
3505                                       ReturnValueSlot ReturnValue);
3506 
3507   RValue EmitCXXOperatorMemberCallExpr(const CXXOperatorCallExpr *E,
3508                                        const CXXMethodDecl *MD,
3509                                        ReturnValueSlot ReturnValue);
3510   RValue EmitCXXPseudoDestructorExpr(const CXXPseudoDestructorExpr *E);
3511 
3512   RValue EmitCUDAKernelCallExpr(const CUDAKernelCallExpr *E,
3513                                 ReturnValueSlot ReturnValue);
3514 
3515   RValue EmitNVPTXDevicePrintfCallExpr(const CallExpr *E,
3516                                        ReturnValueSlot ReturnValue);
3517 
3518   RValue EmitBuiltinExpr(const FunctionDecl *FD,
3519                          unsigned BuiltinID, const CallExpr *E,
3520                          ReturnValueSlot ReturnValue);
3521 
3522   /// Emit IR for __builtin_os_log_format.
3523   RValue emitBuiltinOSLogFormat(const CallExpr &E);
3524 
3525   llvm::Function *generateBuiltinOSLogHelperFunction(
3526       const analyze_os_log::OSLogBufferLayout &Layout,
3527       CharUnits BufferAlignment);
3528 
3529   RValue EmitBlockCallExpr(const CallExpr *E, ReturnValueSlot ReturnValue);
3530 
3531   /// EmitTargetBuiltinExpr - Emit the given builtin call. Returns 0 if the call
3532   /// is unhandled by the current target.
3533   llvm::Value *EmitTargetBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3534 
3535   llvm::Value *EmitAArch64CompareBuiltinExpr(llvm::Value *Op, llvm::Type *Ty,
3536                                              const llvm::CmpInst::Predicate Fp,
3537                                              const llvm::CmpInst::Predicate Ip,
3538                                              const llvm::Twine &Name = "");
3539   llvm::Value *EmitARMBuiltinExpr(unsigned BuiltinID, const CallExpr *E,
3540                                   llvm::Triple::ArchType Arch);
3541 
3542   llvm::Value *EmitCommonNeonBuiltinExpr(unsigned BuiltinID,
3543                                          unsigned LLVMIntrinsic,
3544                                          unsigned AltLLVMIntrinsic,
3545                                          const char *NameHint,
3546                                          unsigned Modifier,
3547                                          const CallExpr *E,
3548                                          SmallVectorImpl<llvm::Value *> &Ops,
3549                                          Address PtrOp0, Address PtrOp1,
3550                                          llvm::Triple::ArchType Arch);
3551 
3552   llvm::Value *EmitISOVolatileLoad(const CallExpr *E);
3553   llvm::Value *EmitISOVolatileStore(const CallExpr *E);
3554 
3555   llvm::Function *LookupNeonLLVMIntrinsic(unsigned IntrinsicID,
3556                                           unsigned Modifier, llvm::Type *ArgTy,
3557                                           const CallExpr *E);
3558   llvm::Value *EmitNeonCall(llvm::Function *F,
3559                             SmallVectorImpl<llvm::Value*> &O,
3560                             const char *name,
3561                             unsigned shift = 0, bool rightshift = false);
3562   llvm::Value *EmitNeonSplat(llvm::Value *V, llvm::Constant *Idx);
3563   llvm::Value *EmitNeonShiftVector(llvm::Value *V, llvm::Type *Ty,
3564                                    bool negateForRightShift);
3565   llvm::Value *EmitNeonRShiftImm(llvm::Value *Vec, llvm::Value *Amt,
3566                                  llvm::Type *Ty, bool usgn, const char *name);
3567   llvm::Value *vectorWrapScalar16(llvm::Value *Op);
3568   llvm::Value *EmitAArch64BuiltinExpr(unsigned BuiltinID, const CallExpr *E,
3569                                       llvm::Triple::ArchType Arch);
3570 
3571   llvm::Value *BuildVector(ArrayRef<llvm::Value*> Ops);
3572   llvm::Value *EmitX86BuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3573   llvm::Value *EmitPPCBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3574   llvm::Value *EmitAMDGPUBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3575   llvm::Value *EmitSystemZBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3576   llvm::Value *EmitNVPTXBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3577   llvm::Value *EmitWebAssemblyBuiltinExpr(unsigned BuiltinID,
3578                                           const CallExpr *E);
3579   llvm::Value *EmitHexagonBuiltinExpr(unsigned BuiltinID, const CallExpr *E);
3580 
3581 private:
3582   enum class MSVCIntrin;
3583 
3584 public:
3585   llvm::Value *EmitMSVCBuiltinExpr(MSVCIntrin BuiltinID, const CallExpr *E);
3586 
3587   llvm::Value *EmitBuiltinAvailable(ArrayRef<llvm::Value *> Args);
3588 
3589   llvm::Value *EmitObjCProtocolExpr(const ObjCProtocolExpr *E);
3590   llvm::Value *EmitObjCStringLiteral(const ObjCStringLiteral *E);
3591   llvm::Value *EmitObjCBoxedExpr(const ObjCBoxedExpr *E);
3592   llvm::Value *EmitObjCArrayLiteral(const ObjCArrayLiteral *E);
3593   llvm::Value *EmitObjCDictionaryLiteral(const ObjCDictionaryLiteral *E);
3594   llvm::Value *EmitObjCCollectionLiteral(const Expr *E,
3595                                 const ObjCMethodDecl *MethodWithObjects);
3596   llvm::Value *EmitObjCSelectorExpr(const ObjCSelectorExpr *E);
3597   RValue EmitObjCMessageExpr(const ObjCMessageExpr *E,
3598                              ReturnValueSlot Return = ReturnValueSlot());
3599 
3600   /// Retrieves the default cleanup kind for an ARC cleanup.
3601   /// Except under -fobjc-arc-eh, ARC cleanups are normal-only.
3602   CleanupKind getARCCleanupKind() {
3603     return CGM.getCodeGenOpts().ObjCAutoRefCountExceptions
3604              ? NormalAndEHCleanup : NormalCleanup;
3605   }
3606 
3607   // ARC primitives.
3608   void EmitARCInitWeak(Address addr, llvm::Value *value);
3609   void EmitARCDestroyWeak(Address addr);
3610   llvm::Value *EmitARCLoadWeak(Address addr);
3611   llvm::Value *EmitARCLoadWeakRetained(Address addr);
3612   llvm::Value *EmitARCStoreWeak(Address addr, llvm::Value *value, bool ignored);
3613   void emitARCCopyAssignWeak(QualType Ty, Address DstAddr, Address SrcAddr);
3614   void emitARCMoveAssignWeak(QualType Ty, Address DstAddr, Address SrcAddr);
3615   void EmitARCCopyWeak(Address dst, Address src);
3616   void EmitARCMoveWeak(Address dst, Address src);
3617   llvm::Value *EmitARCRetainAutorelease(QualType type, llvm::Value *value);
3618   llvm::Value *EmitARCRetainAutoreleaseNonBlock(llvm::Value *value);
3619   llvm::Value *EmitARCStoreStrong(LValue lvalue, llvm::Value *value,
3620                                   bool resultIgnored);
3621   llvm::Value *EmitARCStoreStrongCall(Address addr, llvm::Value *value,
3622                                       bool resultIgnored);
3623   llvm::Value *EmitARCRetain(QualType type, llvm::Value *value);
3624   llvm::Value *EmitARCRetainNonBlock(llvm::Value *value);
3625   llvm::Value *EmitARCRetainBlock(llvm::Value *value, bool mandatory);
3626   void EmitARCDestroyStrong(Address addr, ARCPreciseLifetime_t precise);
3627   void EmitARCRelease(llvm::Value *value, ARCPreciseLifetime_t precise);
3628   llvm::Value *EmitARCAutorelease(llvm::Value *value);
3629   llvm::Value *EmitARCAutoreleaseReturnValue(llvm::Value *value);
3630   llvm::Value *EmitARCRetainAutoreleaseReturnValue(llvm::Value *value);
3631   llvm::Value *EmitARCRetainAutoreleasedReturnValue(llvm::Value *value);
3632   llvm::Value *EmitARCUnsafeClaimAutoreleasedReturnValue(llvm::Value *value);
3633 
3634   std::pair<LValue,llvm::Value*>
3635   EmitARCStoreAutoreleasing(const BinaryOperator *e);
3636   std::pair<LValue,llvm::Value*>
3637   EmitARCStoreStrong(const BinaryOperator *e, bool ignored);
3638   std::pair<LValue,llvm::Value*>
3639   EmitARCStoreUnsafeUnretained(const BinaryOperator *e, bool ignored);
3640 
3641   llvm::Value *EmitObjCThrowOperand(const Expr *expr);
3642   llvm::Value *EmitObjCConsumeObject(QualType T, llvm::Value *Ptr);
3643   llvm::Value *EmitObjCExtendObjectLifetime(QualType T, llvm::Value *Ptr);
3644 
3645   llvm::Value *EmitARCExtendBlockObject(const Expr *expr);
3646   llvm::Value *EmitARCReclaimReturnedObject(const Expr *e,
3647                                             bool allowUnsafeClaim);
3648   llvm::Value *EmitARCRetainScalarExpr(const Expr *expr);
3649   llvm::Value *EmitARCRetainAutoreleaseScalarExpr(const Expr *expr);
3650   llvm::Value *EmitARCUnsafeUnretainedScalarExpr(const Expr *expr);
3651 
3652   void EmitARCIntrinsicUse(ArrayRef<llvm::Value*> values);
3653 
3654   static Destroyer destroyARCStrongImprecise;
3655   static Destroyer destroyARCStrongPrecise;
3656   static Destroyer destroyARCWeak;
3657   static Destroyer emitARCIntrinsicUse;
3658   static Destroyer destroyNonTrivialCStruct;
3659 
3660   void EmitObjCAutoreleasePoolPop(llvm::Value *Ptr);
3661   llvm::Value *EmitObjCAutoreleasePoolPush();
3662   llvm::Value *EmitObjCMRRAutoreleasePoolPush();
3663   void EmitObjCAutoreleasePoolCleanup(llvm::Value *Ptr);
3664   void EmitObjCMRRAutoreleasePoolPop(llvm::Value *Ptr);
3665 
3666   /// Emits a reference binding to the passed in expression.
3667   RValue EmitReferenceBindingToExpr(const Expr *E);
3668 
3669   //===--------------------------------------------------------------------===//
3670   //                           Expression Emission
3671   //===--------------------------------------------------------------------===//
3672 
3673   // Expressions are broken into three classes: scalar, complex, aggregate.
3674 
3675   /// EmitScalarExpr - Emit the computation of the specified expression of LLVM
3676   /// scalar type, returning the result.
3677   llvm::Value *EmitScalarExpr(const Expr *E , bool IgnoreResultAssign = false);
3678 
3679   /// Emit a conversion from the specified type to the specified destination
3680   /// type, both of which are LLVM scalar types.
3681   llvm::Value *EmitScalarConversion(llvm::Value *Src, QualType SrcTy,
3682                                     QualType DstTy, SourceLocation Loc);
3683 
3684   /// Emit a conversion from the specified complex type to the specified
3685   /// destination type, where the destination type is an LLVM scalar type.
3686   llvm::Value *EmitComplexToScalarConversion(ComplexPairTy Src, QualType SrcTy,
3687                                              QualType DstTy,
3688                                              SourceLocation Loc);
3689 
3690   /// EmitAggExpr - Emit the computation of the specified expression
3691   /// of aggregate type.  The result is computed into the given slot,
3692   /// which may be null to indicate that the value is not needed.
3693   void EmitAggExpr(const Expr *E, AggValueSlot AS);
3694 
3695   /// EmitAggExprToLValue - Emit the computation of the specified expression of
3696   /// aggregate type into a temporary LValue.
3697   LValue EmitAggExprToLValue(const Expr *E);
3698 
3699   /// EmitExtendGCLifetime - Given a pointer to an Objective-C object,
3700   /// make sure it survives garbage collection until this point.
3701   void EmitExtendGCLifetime(llvm::Value *object);
3702 
3703   /// EmitComplexExpr - Emit the computation of the specified expression of
3704   /// complex type, returning the result.
3705   ComplexPairTy EmitComplexExpr(const Expr *E,
3706                                 bool IgnoreReal = false,
3707                                 bool IgnoreImag = false);
3708 
3709   /// EmitComplexExprIntoLValue - Emit the given expression of complex
3710   /// type and place its result into the specified l-value.
3711   void EmitComplexExprIntoLValue(const Expr *E, LValue dest, bool isInit);
3712 
3713   /// EmitStoreOfComplex - Store a complex number into the specified l-value.
3714   void EmitStoreOfComplex(ComplexPairTy V, LValue dest, bool isInit);
3715 
3716   /// EmitLoadOfComplex - Load a complex number from the specified l-value.
3717   ComplexPairTy EmitLoadOfComplex(LValue src, SourceLocation loc);
3718 
3719   Address emitAddrOfRealComponent(Address complex, QualType complexType);
3720   Address emitAddrOfImagComponent(Address complex, QualType complexType);
3721 
3722   /// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
3723   /// global variable that has already been created for it.  If the initializer
3724   /// has a different type than GV does, this may free GV and return a different
3725   /// one.  Otherwise it just returns GV.
3726   llvm::GlobalVariable *
3727   AddInitializerToStaticVarDecl(const VarDecl &D,
3728                                 llvm::GlobalVariable *GV);
3729 
3730 
3731   /// EmitCXXGlobalVarDeclInit - Create the initializer for a C++
3732   /// variable with global storage.
3733   void EmitCXXGlobalVarDeclInit(const VarDecl &D, llvm::Constant *DeclPtr,
3734                                 bool PerformInit);
3735 
3736   llvm::Constant *createAtExitStub(const VarDecl &VD, llvm::Constant *Dtor,
3737                                    llvm::Constant *Addr);
3738 
3739   /// Call atexit() with a function that passes the given argument to
3740   /// the given function.
3741   void registerGlobalDtorWithAtExit(const VarDecl &D, llvm::Constant *fn,
3742                                     llvm::Constant *addr);
3743 
3744   /// Call atexit() with function dtorStub.
3745   void registerGlobalDtorWithAtExit(llvm::Constant *dtorStub);
3746 
3747   /// Emit code in this function to perform a guarded variable
3748   /// initialization.  Guarded initializations are used when it's not
3749   /// possible to prove that an initialization will be done exactly
3750   /// once, e.g. with a static local variable or a static data member
3751   /// of a class template.
3752   void EmitCXXGuardedInit(const VarDecl &D, llvm::GlobalVariable *DeclPtr,
3753                           bool PerformInit);
3754 
3755   enum class GuardKind { VariableGuard, TlsGuard };
3756 
3757   /// Emit a branch to select whether or not to perform guarded initialization.
3758   void EmitCXXGuardedInitBranch(llvm::Value *NeedsInit,
3759                                 llvm::BasicBlock *InitBlock,
3760                                 llvm::BasicBlock *NoInitBlock,
3761                                 GuardKind Kind, const VarDecl *D);
3762 
3763   /// GenerateCXXGlobalInitFunc - Generates code for initializing global
3764   /// variables.
3765   void GenerateCXXGlobalInitFunc(llvm::Function *Fn,
3766                                  ArrayRef<llvm::Function *> CXXThreadLocals,
3767                                  Address Guard = Address::invalid());
3768 
3769   /// GenerateCXXGlobalDtorsFunc - Generates code for destroying global
3770   /// variables.
3771   void GenerateCXXGlobalDtorsFunc(
3772       llvm::Function *Fn,
3773       const std::vector<std::pair<llvm::WeakTrackingVH, llvm::Constant *>>
3774           &DtorsAndObjects);
3775 
3776   void GenerateCXXGlobalVarDeclInitFunc(llvm::Function *Fn,
3777                                         const VarDecl *D,
3778                                         llvm::GlobalVariable *Addr,
3779                                         bool PerformInit);
3780 
3781   void EmitCXXConstructExpr(const CXXConstructExpr *E, AggValueSlot Dest);
3782 
3783   void EmitSynthesizedCXXCopyCtor(Address Dest, Address Src, const Expr *Exp);
3784 
3785   void enterFullExpression(const ExprWithCleanups *E) {
3786     if (E->getNumObjects() == 0) return;
3787     enterNonTrivialFullExpression(E);
3788   }
3789   void enterNonTrivialFullExpression(const ExprWithCleanups *E);
3790 
3791   void EmitCXXThrowExpr(const CXXThrowExpr *E, bool KeepInsertionPoint = true);
3792 
3793   void EmitLambdaExpr(const LambdaExpr *E, AggValueSlot Dest);
3794 
3795   RValue EmitAtomicExpr(AtomicExpr *E);
3796 
3797   //===--------------------------------------------------------------------===//
3798   //                         Annotations Emission
3799   //===--------------------------------------------------------------------===//
3800 
3801   /// Emit an annotation call (intrinsic or builtin).
3802   llvm::Value *EmitAnnotationCall(llvm::Value *AnnotationFn,
3803                                   llvm::Value *AnnotatedVal,
3804                                   StringRef AnnotationStr,
3805                                   SourceLocation Location);
3806 
3807   /// Emit local annotations for the local variable V, declared by D.
3808   void EmitVarAnnotations(const VarDecl *D, llvm::Value *V);
3809 
3810   /// Emit field annotations for the given field & value. Returns the
3811   /// annotation result.
3812   Address EmitFieldAnnotations(const FieldDecl *D, Address V);
3813 
3814   //===--------------------------------------------------------------------===//
3815   //                             Internal Helpers
3816   //===--------------------------------------------------------------------===//
3817 
3818   /// ContainsLabel - Return true if the statement contains a label in it.  If
3819   /// this statement is not executed normally, it not containing a label means
3820   /// that we can just remove the code.
3821   static bool ContainsLabel(const Stmt *S, bool IgnoreCaseStmts = false);
3822 
3823   /// containsBreak - Return true if the statement contains a break out of it.
3824   /// If the statement (recursively) contains a switch or loop with a break
3825   /// inside of it, this is fine.
3826   static bool containsBreak(const Stmt *S);
3827 
3828   /// Determine if the given statement might introduce a declaration into the
3829   /// current scope, by being a (possibly-labelled) DeclStmt.
3830   static bool mightAddDeclToScope(const Stmt *S);
3831 
3832   /// ConstantFoldsToSimpleInteger - If the specified expression does not fold
3833   /// to a constant, or if it does but contains a label, return false.  If it
3834   /// constant folds return true and set the boolean result in Result.
3835   bool ConstantFoldsToSimpleInteger(const Expr *Cond, bool &Result,
3836                                     bool AllowLabels = false);
3837 
3838   /// ConstantFoldsToSimpleInteger - If the specified expression does not fold
3839   /// to a constant, or if it does but contains a label, return false.  If it
3840   /// constant folds return true and set the folded value.
3841   bool ConstantFoldsToSimpleInteger(const Expr *Cond, llvm::APSInt &Result,
3842                                     bool AllowLabels = false);
3843 
3844   /// EmitBranchOnBoolExpr - Emit a branch on a boolean condition (e.g. for an
3845   /// if statement) to the specified blocks.  Based on the condition, this might
3846   /// try to simplify the codegen of the conditional based on the branch.
3847   /// TrueCount should be the number of times we expect the condition to
3848   /// evaluate to true based on PGO data.
3849   void EmitBranchOnBoolExpr(const Expr *Cond, llvm::BasicBlock *TrueBlock,
3850                             llvm::BasicBlock *FalseBlock, uint64_t TrueCount);
3851 
3852   /// Given an assignment `*LHS = RHS`, emit a test that checks if \p RHS is
3853   /// nonnull, if \p LHS is marked _Nonnull.
3854   void EmitNullabilityCheck(LValue LHS, llvm::Value *RHS, SourceLocation Loc);
3855 
3856   /// An enumeration which makes it easier to specify whether or not an
3857   /// operation is a subtraction.
3858   enum { NotSubtraction = false, IsSubtraction = true };
3859 
3860   /// Same as IRBuilder::CreateInBoundsGEP, but additionally emits a check to
3861   /// detect undefined behavior when the pointer overflow sanitizer is enabled.
3862   /// \p SignedIndices indicates whether any of the GEP indices are signed.
3863   /// \p IsSubtraction indicates whether the expression used to form the GEP
3864   /// is a subtraction.
3865   llvm::Value *EmitCheckedInBoundsGEP(llvm::Value *Ptr,
3866                                       ArrayRef<llvm::Value *> IdxList,
3867                                       bool SignedIndices,
3868                                       bool IsSubtraction,
3869                                       SourceLocation Loc,
3870                                       const Twine &Name = "");
3871 
3872   /// Specifies which type of sanitizer check to apply when handling a
3873   /// particular builtin.
3874   enum BuiltinCheckKind {
3875     BCK_CTZPassedZero,
3876     BCK_CLZPassedZero,
3877   };
3878 
3879   /// Emits an argument for a call to a builtin. If the builtin sanitizer is
3880   /// enabled, a runtime check specified by \p Kind is also emitted.
3881   llvm::Value *EmitCheckedArgForBuiltin(const Expr *E, BuiltinCheckKind Kind);
3882 
3883   /// Emit a description of a type in a format suitable for passing to
3884   /// a runtime sanitizer handler.
3885   llvm::Constant *EmitCheckTypeDescriptor(QualType T);
3886 
3887   /// Convert a value into a format suitable for passing to a runtime
3888   /// sanitizer handler.
3889   llvm::Value *EmitCheckValue(llvm::Value *V);
3890 
3891   /// Emit a description of a source location in a format suitable for
3892   /// passing to a runtime sanitizer handler.
3893   llvm::Constant *EmitCheckSourceLocation(SourceLocation Loc);
3894 
3895   /// Create a basic block that will call a handler function in a
3896   /// sanitizer runtime with the provided arguments, and create a conditional
3897   /// branch to it.
3898   void EmitCheck(ArrayRef<std::pair<llvm::Value *, SanitizerMask>> Checked,
3899                  SanitizerHandler Check, ArrayRef<llvm::Constant *> StaticArgs,
3900                  ArrayRef<llvm::Value *> DynamicArgs);
3901 
3902   /// Emit a slow path cross-DSO CFI check which calls __cfi_slowpath
3903   /// if Cond if false.
3904   void EmitCfiSlowPathCheck(SanitizerMask Kind, llvm::Value *Cond,
3905                             llvm::ConstantInt *TypeId, llvm::Value *Ptr,
3906                             ArrayRef<llvm::Constant *> StaticArgs);
3907 
3908   /// Emit a reached-unreachable diagnostic if \p Loc is valid and runtime
3909   /// checking is enabled. Otherwise, just emit an unreachable instruction.
3910   void EmitUnreachable(SourceLocation Loc);
3911 
3912   /// Create a basic block that will call the trap intrinsic, and emit a
3913   /// conditional branch to it, for the -ftrapv checks.
3914   void EmitTrapCheck(llvm::Value *Checked);
3915 
3916   /// Emit a call to trap or debugtrap and attach function attribute
3917   /// "trap-func-name" if specified.
3918   llvm::CallInst *EmitTrapCall(llvm::Intrinsic::ID IntrID);
3919 
3920   /// Emit a stub for the cross-DSO CFI check function.
3921   void EmitCfiCheckStub();
3922 
3923   /// Emit a cross-DSO CFI failure handling function.
3924   void EmitCfiCheckFail();
3925 
3926   /// Create a check for a function parameter that may potentially be
3927   /// declared as non-null.
3928   void EmitNonNullArgCheck(RValue RV, QualType ArgType, SourceLocation ArgLoc,
3929                            AbstractCallee AC, unsigned ParmNum);
3930 
3931   /// EmitCallArg - Emit a single call argument.
3932   void EmitCallArg(CallArgList &args, const Expr *E, QualType ArgType);
3933 
3934   /// EmitDelegateCallArg - We are performing a delegate call; that
3935   /// is, the current function is delegating to another one.  Produce
3936   /// a r-value suitable for passing the given parameter.
3937   void EmitDelegateCallArg(CallArgList &args, const VarDecl *param,
3938                            SourceLocation loc);
3939 
3940   /// SetFPAccuracy - Set the minimum required accuracy of the given floating
3941   /// point operation, expressed as the maximum relative error in ulp.
3942   void SetFPAccuracy(llvm::Value *Val, float Accuracy);
3943 
3944 private:
3945   llvm::MDNode *getRangeForLoadFromType(QualType Ty);
3946   void EmitReturnOfRValue(RValue RV, QualType Ty);
3947 
3948   void deferPlaceholderReplacement(llvm::Instruction *Old, llvm::Value *New);
3949 
3950   llvm::SmallVector<std::pair<llvm::Instruction *, llvm::Value *>, 4>
3951   DeferredReplacements;
3952 
3953   /// Set the address of a local variable.
3954   void setAddrOfLocalVar(const VarDecl *VD, Address Addr) {
3955     assert(!LocalDeclMap.count(VD) && "Decl already exists in LocalDeclMap!");
3956     LocalDeclMap.insert({VD, Addr});
3957   }
3958 
3959   /// ExpandTypeFromArgs - Reconstruct a structure of type \arg Ty
3960   /// from function arguments into \arg Dst. See ABIArgInfo::Expand.
3961   ///
3962   /// \param AI - The first function argument of the expansion.
3963   void ExpandTypeFromArgs(QualType Ty, LValue Dst,
3964                           SmallVectorImpl<llvm::Value *>::iterator &AI);
3965 
3966   /// ExpandTypeToArgs - Expand an CallArg \arg Arg, with the LLVM type for \arg
3967   /// Ty, into individual arguments on the provided vector \arg IRCallArgs,
3968   /// starting at index \arg IRCallArgPos. See ABIArgInfo::Expand.
3969   void ExpandTypeToArgs(QualType Ty, CallArg Arg, llvm::FunctionType *IRFuncTy,
3970                         SmallVectorImpl<llvm::Value *> &IRCallArgs,
3971                         unsigned &IRCallArgPos);
3972 
3973   llvm::Value* EmitAsmInput(const TargetInfo::ConstraintInfo &Info,
3974                             const Expr *InputExpr, std::string &ConstraintStr);
3975 
3976   llvm::Value* EmitAsmInputLValue(const TargetInfo::ConstraintInfo &Info,
3977                                   LValue InputValue, QualType InputType,
3978                                   std::string &ConstraintStr,
3979                                   SourceLocation Loc);
3980 
3981   /// Attempts to statically evaluate the object size of E. If that
3982   /// fails, emits code to figure the size of E out for us. This is
3983   /// pass_object_size aware.
3984   ///
3985   /// If EmittedExpr is non-null, this will use that instead of re-emitting E.
3986   llvm::Value *evaluateOrEmitBuiltinObjectSize(const Expr *E, unsigned Type,
3987                                                llvm::IntegerType *ResType,
3988                                                llvm::Value *EmittedE);
3989 
3990   /// Emits the size of E, as required by __builtin_object_size. This
3991   /// function is aware of pass_object_size parameters, and will act accordingly
3992   /// if E is a parameter with the pass_object_size attribute.
3993   llvm::Value *emitBuiltinObjectSize(const Expr *E, unsigned Type,
3994                                      llvm::IntegerType *ResType,
3995                                      llvm::Value *EmittedE);
3996 
3997 public:
3998 #ifndef NDEBUG
3999   // Determine whether the given argument is an Objective-C method
4000   // that may have type parameters in its signature.
4001   static bool isObjCMethodWithTypeParams(const ObjCMethodDecl *method) {
4002     const DeclContext *dc = method->getDeclContext();
4003     if (const ObjCInterfaceDecl *classDecl= dyn_cast<ObjCInterfaceDecl>(dc)) {
4004       return classDecl->getTypeParamListAsWritten();
4005     }
4006 
4007     if (const ObjCCategoryDecl *catDecl = dyn_cast<ObjCCategoryDecl>(dc)) {
4008       return catDecl->getTypeParamList();
4009     }
4010 
4011     return false;
4012   }
4013 
4014   template<typename T>
4015   static bool isObjCMethodWithTypeParams(const T *) { return false; }
4016 #endif
4017 
4018   enum class EvaluationOrder {
4019     ///! No language constraints on evaluation order.
4020     Default,
4021     ///! Language semantics require left-to-right evaluation.
4022     ForceLeftToRight,
4023     ///! Language semantics require right-to-left evaluation.
4024     ForceRightToLeft
4025   };
4026 
4027   /// EmitCallArgs - Emit call arguments for a function.
4028   template <typename T>
4029   void EmitCallArgs(CallArgList &Args, const T *CallArgTypeInfo,
4030                     llvm::iterator_range<CallExpr::const_arg_iterator> ArgRange,
4031                     AbstractCallee AC = AbstractCallee(),
4032                     unsigned ParamsToSkip = 0,
4033                     EvaluationOrder Order = EvaluationOrder::Default) {
4034     SmallVector<QualType, 16> ArgTypes;
4035     CallExpr::const_arg_iterator Arg = ArgRange.begin();
4036 
4037     assert((ParamsToSkip == 0 || CallArgTypeInfo) &&
4038            "Can't skip parameters if type info is not provided");
4039     if (CallArgTypeInfo) {
4040 #ifndef NDEBUG
4041       bool isGenericMethod = isObjCMethodWithTypeParams(CallArgTypeInfo);
4042 #endif
4043 
4044       // First, use the argument types that the type info knows about
4045       for (auto I = CallArgTypeInfo->param_type_begin() + ParamsToSkip,
4046                 E = CallArgTypeInfo->param_type_end();
4047            I != E; ++I, ++Arg) {
4048         assert(Arg != ArgRange.end() && "Running over edge of argument list!");
4049         assert((isGenericMethod ||
4050                 ((*I)->isVariablyModifiedType() ||
4051                  (*I).getNonReferenceType()->isObjCRetainableType() ||
4052                  getContext()
4053                          .getCanonicalType((*I).getNonReferenceType())
4054                          .getTypePtr() ==
4055                      getContext()
4056                          .getCanonicalType((*Arg)->getType())
4057                          .getTypePtr())) &&
4058                "type mismatch in call argument!");
4059         ArgTypes.push_back(*I);
4060       }
4061     }
4062 
4063     // Either we've emitted all the call args, or we have a call to variadic
4064     // function.
4065     assert((Arg == ArgRange.end() || !CallArgTypeInfo ||
4066             CallArgTypeInfo->isVariadic()) &&
4067            "Extra arguments in non-variadic function!");
4068 
4069     // If we still have any arguments, emit them using the type of the argument.
4070     for (auto *A : llvm::make_range(Arg, ArgRange.end()))
4071       ArgTypes.push_back(CallArgTypeInfo ? getVarArgType(A) : A->getType());
4072 
4073     EmitCallArgs(Args, ArgTypes, ArgRange, AC, ParamsToSkip, Order);
4074   }
4075 
4076   void EmitCallArgs(CallArgList &Args, ArrayRef<QualType> ArgTypes,
4077                     llvm::iterator_range<CallExpr::const_arg_iterator> ArgRange,
4078                     AbstractCallee AC = AbstractCallee(),
4079                     unsigned ParamsToSkip = 0,
4080                     EvaluationOrder Order = EvaluationOrder::Default);
4081 
4082   /// EmitPointerWithAlignment - Given an expression with a pointer type,
4083   /// emit the value and compute our best estimate of the alignment of the
4084   /// pointee.
4085   ///
4086   /// \param BaseInfo - If non-null, this will be initialized with
4087   /// information about the source of the alignment and the may-alias
4088   /// attribute.  Note that this function will conservatively fall back on
4089   /// the type when it doesn't recognize the expression and may-alias will
4090   /// be set to false.
4091   ///
4092   /// One reasonable way to use this information is when there's a language
4093   /// guarantee that the pointer must be aligned to some stricter value, and
4094   /// we're simply trying to ensure that sufficiently obvious uses of under-
4095   /// aligned objects don't get miscompiled; for example, a placement new
4096   /// into the address of a local variable.  In such a case, it's quite
4097   /// reasonable to just ignore the returned alignment when it isn't from an
4098   /// explicit source.
4099   Address EmitPointerWithAlignment(const Expr *Addr,
4100                                    LValueBaseInfo *BaseInfo = nullptr,
4101                                    TBAAAccessInfo *TBAAInfo = nullptr);
4102 
4103   /// If \p E references a parameter with pass_object_size info or a constant
4104   /// array size modifier, emit the object size divided by the size of \p EltTy.
4105   /// Otherwise return null.
4106   llvm::Value *LoadPassedObjectSize(const Expr *E, QualType EltTy);
4107 
4108   void EmitSanitizerStatReport(llvm::SanitizerStatKind SSK);
4109 
4110   struct MultiVersionResolverOption {
4111     llvm::Function *Function;
4112     TargetAttr::ParsedTargetAttr ParsedAttribute;
4113     unsigned Priority;
4114     MultiVersionResolverOption(const TargetInfo &TargInfo, llvm::Function *F,
4115                                const clang::TargetAttr::ParsedTargetAttr &PT)
4116         : Function(F), ParsedAttribute(PT), Priority(0u) {
4117       for (StringRef Feat : PT.Features)
4118         Priority = std::max(Priority,
4119                             TargInfo.multiVersionSortPriority(Feat.substr(1)));
4120 
4121       if (!PT.Architecture.empty())
4122         Priority = std::max(Priority,
4123                             TargInfo.multiVersionSortPriority(PT.Architecture));
4124     }
4125 
4126     bool operator>(const MultiVersionResolverOption &Other) const {
4127       return Priority > Other.Priority;
4128     }
4129   };
4130   void EmitMultiVersionResolver(llvm::Function *Resolver,
4131                                 ArrayRef<MultiVersionResolverOption> Options);
4132 
4133 private:
4134   QualType getVarArgType(const Expr *Arg);
4135 
4136   void EmitDeclMetadata();
4137 
4138   BlockByrefHelpers *buildByrefHelpers(llvm::StructType &byrefType,
4139                                   const AutoVarEmission &emission);
4140 
4141   void AddObjCARCExceptionMetadata(llvm::Instruction *Inst);
4142 
4143   llvm::Value *GetValueForARMHint(unsigned BuiltinID);
4144   llvm::Value *EmitX86CpuIs(const CallExpr *E);
4145   llvm::Value *EmitX86CpuIs(StringRef CPUStr);
4146   llvm::Value *EmitX86CpuSupports(const CallExpr *E);
4147   llvm::Value *EmitX86CpuSupports(ArrayRef<StringRef> FeatureStrs);
4148   llvm::Value *EmitX86CpuInit();
4149   llvm::Value *FormResolverCondition(const MultiVersionResolverOption &RO);
4150 };
4151 
4152 /// Helper class with most of the code for saving a value for a
4153 /// conditional expression cleanup.
4154 struct DominatingLLVMValue {
4155   typedef llvm::PointerIntPair<llvm::Value*, 1, bool> saved_type;
4156 
4157   /// Answer whether the given value needs extra work to be saved.
4158   static bool needsSaving(llvm::Value *value) {
4159     // If it's not an instruction, we don't need to save.
4160     if (!isa<llvm::Instruction>(value)) return false;
4161 
4162     // If it's an instruction in the entry block, we don't need to save.
4163     llvm::BasicBlock *block = cast<llvm::Instruction>(value)->getParent();
4164     return (block != &block->getParent()->getEntryBlock());
4165   }
4166 
4167   /// Try to save the given value.
4168   static saved_type save(CodeGenFunction &CGF, llvm::Value *value) {
4169     if (!needsSaving(value)) return saved_type(value, false);
4170 
4171     // Otherwise, we need an alloca.
4172     auto align = CharUnits::fromQuantity(
4173               CGF.CGM.getDataLayout().getPrefTypeAlignment(value->getType()));
4174     Address alloca =
4175       CGF.CreateTempAlloca(value->getType(), align, "cond-cleanup.save");
4176     CGF.Builder.CreateStore(value, alloca);
4177 
4178     return saved_type(alloca.getPointer(), true);
4179   }
4180 
4181   static llvm::Value *restore(CodeGenFunction &CGF, saved_type value) {
4182     // If the value says it wasn't saved, trust that it's still dominating.
4183     if (!value.getInt()) return value.getPointer();
4184 
4185     // Otherwise, it should be an alloca instruction, as set up in save().
4186     auto alloca = cast<llvm::AllocaInst>(value.getPointer());
4187     return CGF.Builder.CreateAlignedLoad(alloca, alloca->getAlignment());
4188   }
4189 };
4190 
4191 /// A partial specialization of DominatingValue for llvm::Values that
4192 /// might be llvm::Instructions.
4193 template <class T> struct DominatingPointer<T,true> : DominatingLLVMValue {
4194   typedef T *type;
4195   static type restore(CodeGenFunction &CGF, saved_type value) {
4196     return static_cast<T*>(DominatingLLVMValue::restore(CGF, value));
4197   }
4198 };
4199 
4200 /// A specialization of DominatingValue for Address.
4201 template <> struct DominatingValue<Address> {
4202   typedef Address type;
4203 
4204   struct saved_type {
4205     DominatingLLVMValue::saved_type SavedValue;
4206     CharUnits Alignment;
4207   };
4208 
4209   static bool needsSaving(type value) {
4210     return DominatingLLVMValue::needsSaving(value.getPointer());
4211   }
4212   static saved_type save(CodeGenFunction &CGF, type value) {
4213     return { DominatingLLVMValue::save(CGF, value.getPointer()),
4214              value.getAlignment() };
4215   }
4216   static type restore(CodeGenFunction &CGF, saved_type value) {
4217     return Address(DominatingLLVMValue::restore(CGF, value.SavedValue),
4218                    value.Alignment);
4219   }
4220 };
4221 
4222 /// A specialization of DominatingValue for RValue.
4223 template <> struct DominatingValue<RValue> {
4224   typedef RValue type;
4225   class saved_type {
4226     enum Kind { ScalarLiteral, ScalarAddress, AggregateLiteral,
4227                 AggregateAddress, ComplexAddress };
4228 
4229     llvm::Value *Value;
4230     unsigned K : 3;
4231     unsigned Align : 29;
4232     saved_type(llvm::Value *v, Kind k, unsigned a = 0)
4233       : Value(v), K(k), Align(a) {}
4234 
4235   public:
4236     static bool needsSaving(RValue value);
4237     static saved_type save(CodeGenFunction &CGF, RValue value);
4238     RValue restore(CodeGenFunction &CGF);
4239 
4240     // implementations in CGCleanup.cpp
4241   };
4242 
4243   static bool needsSaving(type value) {
4244     return saved_type::needsSaving(value);
4245   }
4246   static saved_type save(CodeGenFunction &CGF, type value) {
4247     return saved_type::save(CGF, value);
4248   }
4249   static type restore(CodeGenFunction &CGF, saved_type value) {
4250     return value.restore(CGF);
4251   }
4252 };
4253 
4254 }  // end namespace CodeGen
4255 }  // end namespace clang
4256 
4257 #endif
4258