1 //===--- CGDecl.cpp - Emit LLVM Code for declarations ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This contains code to emit Decl nodes as LLVM code.
12 //===----------------------------------------------------------------------===//
16 #include "CGCleanup.h"
17 #include "CGDebugInfo.h"
18 #include "CGOpenCLRuntime.h"
19 #include "CGOpenMPRuntime.h"
20 #include "CodeGenFunction.h"
21 #include "CodeGenModule.h"
22 #include "TargetInfo.h"
23 #include "clang/AST/ASTContext.h"
24 #include "clang/AST/CharUnits.h"
25 #include "clang/AST/Decl.h"
26 #include "clang/AST/DeclObjC.h"
27 #include "clang/AST/DeclOpenMP.h"
28 #include "clang/Basic/SourceManager.h"
29 #include "clang/Basic/TargetInfo.h"
30 #include "clang/CodeGen/CGFunctionInfo.h"
31 #include "clang/Frontend/CodeGenOptions.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/GlobalVariable.h"
34 #include "llvm/IR/Intrinsics.h"
35 #include "llvm/IR/Type.h"
37 using namespace clang;
38 using namespace CodeGen;
40 void CodeGenFunction::EmitDecl(const Decl &D) {
41 switch (D.getKind()) {
42 case Decl::BuiltinTemplate:
43 case Decl::TranslationUnit:
44 case Decl::ExternCContext:
46 case Decl::UnresolvedUsingTypename:
47 case Decl::ClassTemplateSpecialization:
48 case Decl::ClassTemplatePartialSpecialization:
49 case Decl::VarTemplateSpecialization:
50 case Decl::VarTemplatePartialSpecialization:
51 case Decl::TemplateTypeParm:
52 case Decl::UnresolvedUsingValue:
53 case Decl::NonTypeTemplateParm:
54 case Decl::CXXDeductionGuide:
56 case Decl::CXXConstructor:
57 case Decl::CXXDestructor:
58 case Decl::CXXConversion:
60 case Decl::MSProperty:
61 case Decl::IndirectField:
63 case Decl::ObjCAtDefsField:
65 case Decl::ImplicitParam:
66 case Decl::ClassTemplate:
67 case Decl::VarTemplate:
68 case Decl::FunctionTemplate:
69 case Decl::TypeAliasTemplate:
70 case Decl::TemplateTemplateParm:
71 case Decl::ObjCMethod:
72 case Decl::ObjCCategory:
73 case Decl::ObjCProtocol:
74 case Decl::ObjCInterface:
75 case Decl::ObjCCategoryImpl:
76 case Decl::ObjCImplementation:
77 case Decl::ObjCProperty:
78 case Decl::ObjCCompatibleAlias:
79 case Decl::PragmaComment:
80 case Decl::PragmaDetectMismatch:
81 case Decl::AccessSpec:
82 case Decl::LinkageSpec:
84 case Decl::ObjCPropertyImpl:
85 case Decl::FileScopeAsm:
87 case Decl::FriendTemplate:
90 case Decl::ClassScopeFunctionSpecialization:
91 case Decl::UsingShadow:
92 case Decl::ConstructorUsingShadow:
93 case Decl::ObjCTypeParam:
95 llvm_unreachable("Declaration should not be in declstmts!");
96 case Decl::Function: // void X();
97 case Decl::Record: // struct/union/class X;
98 case Decl::Enum: // enum X;
99 case Decl::EnumConstant: // enum ? { X = ? }
100 case Decl::CXXRecord: // struct/union/class X; [C++]
101 case Decl::StaticAssert: // static_assert(X, ""); [C++0x]
102 case Decl::Label: // __label__ x;
104 case Decl::OMPThreadPrivate:
105 case Decl::OMPCapturedExpr:
107 // None of these decls require codegen support.
110 case Decl::NamespaceAlias:
111 if (CGDebugInfo *DI = getDebugInfo())
112 DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(D));
114 case Decl::Using: // using X; [C++]
115 if (CGDebugInfo *DI = getDebugInfo())
116 DI->EmitUsingDecl(cast<UsingDecl>(D));
118 case Decl::UsingPack:
119 for (auto *Using : cast<UsingPackDecl>(D).expansions())
122 case Decl::UsingDirective: // using namespace X; [C++]
123 if (CGDebugInfo *DI = getDebugInfo())
124 DI->EmitUsingDirective(cast<UsingDirectiveDecl>(D));
127 case Decl::Decomposition: {
128 const VarDecl &VD = cast<VarDecl>(D);
129 assert(VD.isLocalVarDecl() &&
130 "Should not see file-scope variables inside a function!");
132 if (auto *DD = dyn_cast<DecompositionDecl>(&VD))
133 for (auto *B : DD->bindings())
134 if (auto *HD = B->getHoldingVar())
139 case Decl::OMPDeclareReduction:
140 return CGM.EmitOMPDeclareReduction(cast<OMPDeclareReductionDecl>(&D), this);
142 case Decl::Typedef: // typedef int X;
143 case Decl::TypeAlias: { // using X = int; [C++0x]
144 const TypedefNameDecl &TD = cast<TypedefNameDecl>(D);
145 QualType Ty = TD.getUnderlyingType();
147 if (Ty->isVariablyModifiedType())
148 EmitVariablyModifiedType(Ty);
153 /// EmitVarDecl - This method handles emission of any variable declaration
154 /// inside a function, including static vars etc.
155 void CodeGenFunction::EmitVarDecl(const VarDecl &D) {
156 if (D.hasExternalStorage())
157 // Don't emit it now, allow it to be emitted lazily on its first use.
160 // Some function-scope variable does not have static storage but still
161 // needs to be emitted like a static variable, e.g. a function-scope
162 // variable in constant address space in OpenCL.
163 if (D.getStorageDuration() != SD_Automatic) {
164 llvm::GlobalValue::LinkageTypes Linkage =
165 CGM.getLLVMLinkageVarDefinition(&D, /*isConstant=*/false);
167 // FIXME: We need to force the emission/use of a guard variable for
168 // some variables even if we can constant-evaluate them because
169 // we can't guarantee every translation unit will constant-evaluate them.
171 return EmitStaticVarDecl(D, Linkage);
174 if (D.getType().getAddressSpace() == LangAS::opencl_local)
175 return CGM.getOpenCLRuntime().EmitWorkGroupLocalVarDecl(*this, D);
177 assert(D.hasLocalStorage());
178 return EmitAutoVarDecl(D);
181 static std::string getStaticDeclName(CodeGenModule &CGM, const VarDecl &D) {
182 if (CGM.getLangOpts().CPlusPlus)
183 return CGM.getMangledName(&D).str();
185 // If this isn't C++, we don't need a mangled name, just a pretty one.
186 assert(!D.isExternallyVisible() && "name shouldn't matter");
187 std::string ContextName;
188 const DeclContext *DC = D.getDeclContext();
189 if (auto *CD = dyn_cast<CapturedDecl>(DC))
190 DC = cast<DeclContext>(CD->getNonClosureContext());
191 if (const auto *FD = dyn_cast<FunctionDecl>(DC))
192 ContextName = CGM.getMangledName(FD);
193 else if (const auto *BD = dyn_cast<BlockDecl>(DC))
194 ContextName = CGM.getBlockMangledName(GlobalDecl(), BD);
195 else if (const auto *OMD = dyn_cast<ObjCMethodDecl>(DC))
196 ContextName = OMD->getSelector().getAsString();
198 llvm_unreachable("Unknown context for static var decl");
200 ContextName += "." + D.getNameAsString();
204 llvm::Constant *CodeGenModule::getOrCreateStaticVarDecl(
205 const VarDecl &D, llvm::GlobalValue::LinkageTypes Linkage) {
206 // In general, we don't always emit static var decls once before we reference
207 // them. It is possible to reference them before emitting the function that
208 // contains them, and it is possible to emit the containing function multiple
210 if (llvm::Constant *ExistingGV = StaticLocalDeclMap[&D])
213 QualType Ty = D.getType();
214 assert(Ty->isConstantSizeType() && "VLAs can't be static");
216 // Use the label if the variable is renamed with the asm-label extension.
218 if (D.hasAttr<AsmLabelAttr>())
219 Name = getMangledName(&D);
221 Name = getStaticDeclName(*this, D);
223 llvm::Type *LTy = getTypes().ConvertTypeForMem(Ty);
225 GetGlobalVarAddressSpace(&D, getContext().getTargetAddressSpace(Ty));
227 // Local address space cannot have an initializer.
228 llvm::Constant *Init = nullptr;
229 if (Ty.getAddressSpace() != LangAS::opencl_local)
230 Init = EmitNullConstant(Ty);
232 Init = llvm::UndefValue::get(LTy);
234 llvm::GlobalVariable *GV =
235 new llvm::GlobalVariable(getModule(), LTy,
236 Ty.isConstant(getContext()), Linkage,
238 llvm::GlobalVariable::NotThreadLocal,
240 GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
241 setGlobalVisibility(GV, &D);
243 if (supportsCOMDAT() && GV->isWeakForLinker())
244 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
249 if (D.isExternallyVisible()) {
250 if (D.hasAttr<DLLImportAttr>())
251 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
252 else if (D.hasAttr<DLLExportAttr>())
253 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
256 // Make sure the result is of the correct type.
257 unsigned ExpectedAddrSpace = getContext().getTargetAddressSpace(Ty);
258 llvm::Constant *Addr = GV;
259 if (AddrSpace != ExpectedAddrSpace) {
260 llvm::PointerType *PTy = llvm::PointerType::get(LTy, ExpectedAddrSpace);
261 Addr = llvm::ConstantExpr::getAddrSpaceCast(GV, PTy);
264 setStaticLocalDeclAddress(&D, Addr);
266 // Ensure that the static local gets initialized by making sure the parent
267 // function gets emitted eventually.
268 const Decl *DC = cast<Decl>(D.getDeclContext());
270 // We can't name blocks or captured statements directly, so try to emit their
272 if (isa<BlockDecl>(DC) || isa<CapturedDecl>(DC)) {
273 DC = DC->getNonClosureContext();
274 // FIXME: Ensure that global blocks get emitted.
280 if (const auto *CD = dyn_cast<CXXConstructorDecl>(DC))
281 GD = GlobalDecl(CD, Ctor_Base);
282 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(DC))
283 GD = GlobalDecl(DD, Dtor_Base);
284 else if (const auto *FD = dyn_cast<FunctionDecl>(DC))
287 // Don't do anything for Obj-C method decls or global closures. We should
289 assert(isa<ObjCMethodDecl>(DC) && "unexpected parent code decl");
292 (void)GetAddrOfGlobal(GD);
297 /// hasNontrivialDestruction - Determine whether a type's destruction is
298 /// non-trivial. If so, and the variable uses static initialization, we must
299 /// register its destructor to run on exit.
300 static bool hasNontrivialDestruction(QualType T) {
301 CXXRecordDecl *RD = T->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
302 return RD && !RD->hasTrivialDestructor();
305 /// AddInitializerToStaticVarDecl - Add the initializer for 'D' to the
306 /// global variable that has already been created for it. If the initializer
307 /// has a different type than GV does, this may free GV and return a different
308 /// one. Otherwise it just returns GV.
309 llvm::GlobalVariable *
310 CodeGenFunction::AddInitializerToStaticVarDecl(const VarDecl &D,
311 llvm::GlobalVariable *GV) {
312 llvm::Constant *Init = CGM.EmitConstantInit(D, this);
314 // If constant emission failed, then this should be a C++ static
317 if (!getLangOpts().CPlusPlus)
318 CGM.ErrorUnsupported(D.getInit(), "constant l-value expression");
319 else if (HaveInsertPoint()) {
320 // Since we have a static initializer, this global variable can't
322 GV->setConstant(false);
324 EmitCXXGuardedInit(D, GV, /*PerformInit*/true);
329 // The initializer may differ in type from the global. Rewrite
330 // the global to match the initializer. (We have to do this
331 // because some types, like unions, can't be completely represented
332 // in the LLVM type system.)
333 if (GV->getType()->getElementType() != Init->getType()) {
334 llvm::GlobalVariable *OldGV = GV;
336 GV = new llvm::GlobalVariable(CGM.getModule(), Init->getType(),
338 OldGV->getLinkage(), Init, "",
339 /*InsertBefore*/ OldGV,
340 OldGV->getThreadLocalMode(),
341 CGM.getContext().getTargetAddressSpace(D.getType()));
342 GV->setVisibility(OldGV->getVisibility());
343 GV->setComdat(OldGV->getComdat());
345 // Steal the name of the old global
348 // Replace all uses of the old global with the new global
349 llvm::Constant *NewPtrForOldDecl =
350 llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
351 OldGV->replaceAllUsesWith(NewPtrForOldDecl);
353 // Erase the old global, since it is no longer used.
354 OldGV->eraseFromParent();
357 GV->setConstant(CGM.isTypeConstant(D.getType(), true));
358 GV->setInitializer(Init);
360 if (hasNontrivialDestruction(D.getType()) && HaveInsertPoint()) {
361 // We have a constant initializer, but a nontrivial destructor. We still
362 // need to perform a guarded "initialization" in order to register the
364 EmitCXXGuardedInit(D, GV, /*PerformInit*/false);
370 void CodeGenFunction::EmitStaticVarDecl(const VarDecl &D,
371 llvm::GlobalValue::LinkageTypes Linkage) {
372 // Check to see if we already have a global variable for this
373 // declaration. This can happen when double-emitting function
374 // bodies, e.g. with complete and base constructors.
375 llvm::Constant *addr = CGM.getOrCreateStaticVarDecl(D, Linkage);
376 CharUnits alignment = getContext().getDeclAlign(&D);
378 // Store into LocalDeclMap before generating initializer to handle
379 // circular references.
380 setAddrOfLocalVar(&D, Address(addr, alignment));
382 // We can't have a VLA here, but we can have a pointer to a VLA,
383 // even though that doesn't really make any sense.
384 // Make sure to evaluate VLA bounds now so that we have them for later.
385 if (D.getType()->isVariablyModifiedType())
386 EmitVariablyModifiedType(D.getType());
388 // Save the type in case adding the initializer forces a type change.
389 llvm::Type *expectedType = addr->getType();
391 llvm::GlobalVariable *var =
392 cast<llvm::GlobalVariable>(addr->stripPointerCasts());
394 // CUDA's local and local static __shared__ variables should not
395 // have any non-empty initializers. This is ensured by Sema.
396 // Whatever initializer such variable may have when it gets here is
397 // a no-op and should not be emitted.
398 bool isCudaSharedVar = getLangOpts().CUDA && getLangOpts().CUDAIsDevice &&
399 D.hasAttr<CUDASharedAttr>();
400 // If this value has an initializer, emit it.
401 if (D.getInit() && !isCudaSharedVar)
402 var = AddInitializerToStaticVarDecl(D, var);
404 var->setAlignment(alignment.getQuantity());
406 if (D.hasAttr<AnnotateAttr>())
407 CGM.AddGlobalAnnotations(&D, var);
409 if (const SectionAttr *SA = D.getAttr<SectionAttr>())
410 var->setSection(SA->getName());
412 if (D.hasAttr<UsedAttr>())
413 CGM.addUsedGlobal(var);
415 // We may have to cast the constant because of the initializer
418 // FIXME: It is really dangerous to store this in the map; if anyone
419 // RAUW's the GV uses of this constant will be invalid.
420 llvm::Constant *castedAddr =
421 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(var, expectedType);
422 if (var != castedAddr)
423 LocalDeclMap.find(&D)->second = Address(castedAddr, alignment);
424 CGM.setStaticLocalDeclAddress(&D, castedAddr);
426 CGM.getSanitizerMetadata()->reportGlobalToASan(var, D);
428 // Emit global variable debug descriptor for static vars.
429 CGDebugInfo *DI = getDebugInfo();
431 CGM.getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo) {
432 DI->setLocation(D.getLocation());
433 DI->EmitGlobalVariable(var, &D);
438 struct DestroyObject final : EHScopeStack::Cleanup {
439 DestroyObject(Address addr, QualType type,
440 CodeGenFunction::Destroyer *destroyer,
441 bool useEHCleanupForArray)
442 : addr(addr), type(type), destroyer(destroyer),
443 useEHCleanupForArray(useEHCleanupForArray) {}
447 CodeGenFunction::Destroyer *destroyer;
448 bool useEHCleanupForArray;
450 void Emit(CodeGenFunction &CGF, Flags flags) override {
451 // Don't use an EH cleanup recursively from an EH cleanup.
452 bool useEHCleanupForArray =
453 flags.isForNormalCleanup() && this->useEHCleanupForArray;
455 CGF.emitDestroy(addr, type, destroyer, useEHCleanupForArray);
459 struct DestroyNRVOVariable final : EHScopeStack::Cleanup {
460 DestroyNRVOVariable(Address addr,
461 const CXXDestructorDecl *Dtor,
462 llvm::Value *NRVOFlag)
463 : Dtor(Dtor), NRVOFlag(NRVOFlag), Loc(addr) {}
465 const CXXDestructorDecl *Dtor;
466 llvm::Value *NRVOFlag;
469 void Emit(CodeGenFunction &CGF, Flags flags) override {
470 // Along the exceptions path we always execute the dtor.
471 bool NRVO = flags.isForNormalCleanup() && NRVOFlag;
473 llvm::BasicBlock *SkipDtorBB = nullptr;
475 // If we exited via NRVO, we skip the destructor call.
476 llvm::BasicBlock *RunDtorBB = CGF.createBasicBlock("nrvo.unused");
477 SkipDtorBB = CGF.createBasicBlock("nrvo.skipdtor");
478 llvm::Value *DidNRVO =
479 CGF.Builder.CreateFlagLoad(NRVOFlag, "nrvo.val");
480 CGF.Builder.CreateCondBr(DidNRVO, SkipDtorBB, RunDtorBB);
481 CGF.EmitBlock(RunDtorBB);
484 CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
485 /*ForVirtualBase=*/false,
486 /*Delegating=*/false,
489 if (NRVO) CGF.EmitBlock(SkipDtorBB);
493 struct CallStackRestore final : EHScopeStack::Cleanup {
495 CallStackRestore(Address Stack) : Stack(Stack) {}
496 void Emit(CodeGenFunction &CGF, Flags flags) override {
497 llvm::Value *V = CGF.Builder.CreateLoad(Stack);
498 llvm::Value *F = CGF.CGM.getIntrinsic(llvm::Intrinsic::stackrestore);
499 CGF.Builder.CreateCall(F, V);
503 struct ExtendGCLifetime final : EHScopeStack::Cleanup {
505 ExtendGCLifetime(const VarDecl *var) : Var(*var) {}
507 void Emit(CodeGenFunction &CGF, Flags flags) override {
508 // Compute the address of the local variable, in case it's a
509 // byref or something.
510 DeclRefExpr DRE(const_cast<VarDecl*>(&Var), false,
511 Var.getType(), VK_LValue, SourceLocation());
512 llvm::Value *value = CGF.EmitLoadOfScalar(CGF.EmitDeclRefLValue(&DRE),
514 CGF.EmitExtendGCLifetime(value);
518 struct CallCleanupFunction final : EHScopeStack::Cleanup {
519 llvm::Constant *CleanupFn;
520 const CGFunctionInfo &FnInfo;
523 CallCleanupFunction(llvm::Constant *CleanupFn, const CGFunctionInfo *Info,
525 : CleanupFn(CleanupFn), FnInfo(*Info), Var(*Var) {}
527 void Emit(CodeGenFunction &CGF, Flags flags) override {
528 DeclRefExpr DRE(const_cast<VarDecl*>(&Var), false,
529 Var.getType(), VK_LValue, SourceLocation());
530 // Compute the address of the local variable, in case it's a byref
532 llvm::Value *Addr = CGF.EmitDeclRefLValue(&DRE).getPointer();
534 // In some cases, the type of the function argument will be different from
535 // the type of the pointer. An example of this is
536 // void f(void* arg);
537 // __attribute__((cleanup(f))) void *g;
539 // To fix this we insert a bitcast here.
540 QualType ArgTy = FnInfo.arg_begin()->type;
542 CGF.Builder.CreateBitCast(Addr, CGF.ConvertType(ArgTy));
545 Args.add(RValue::get(Arg),
546 CGF.getContext().getPointerType(Var.getType()));
547 auto Callee = CGCallee::forDirect(CleanupFn);
548 CGF.EmitCall(FnInfo, Callee, ReturnValueSlot(), Args);
551 } // end anonymous namespace
553 /// EmitAutoVarWithLifetime - Does the setup required for an automatic
554 /// variable with lifetime.
555 static void EmitAutoVarWithLifetime(CodeGenFunction &CGF, const VarDecl &var,
557 Qualifiers::ObjCLifetime lifetime) {
559 case Qualifiers::OCL_None:
560 llvm_unreachable("present but none");
562 case Qualifiers::OCL_ExplicitNone:
566 case Qualifiers::OCL_Strong: {
567 CodeGenFunction::Destroyer *destroyer =
568 (var.hasAttr<ObjCPreciseLifetimeAttr>()
569 ? CodeGenFunction::destroyARCStrongPrecise
570 : CodeGenFunction::destroyARCStrongImprecise);
572 CleanupKind cleanupKind = CGF.getARCCleanupKind();
573 CGF.pushDestroy(cleanupKind, addr, var.getType(), destroyer,
574 cleanupKind & EHCleanup);
577 case Qualifiers::OCL_Autoreleasing:
581 case Qualifiers::OCL_Weak:
582 // __weak objects always get EH cleanups; otherwise, exceptions
583 // could cause really nasty crashes instead of mere leaks.
584 CGF.pushDestroy(NormalAndEHCleanup, addr, var.getType(),
585 CodeGenFunction::destroyARCWeak,
586 /*useEHCleanup*/ true);
591 static bool isAccessedBy(const VarDecl &var, const Stmt *s) {
592 if (const Expr *e = dyn_cast<Expr>(s)) {
593 // Skip the most common kinds of expressions that make
594 // hierarchy-walking expensive.
595 s = e = e->IgnoreParenCasts();
597 if (const DeclRefExpr *ref = dyn_cast<DeclRefExpr>(e))
598 return (ref->getDecl() == &var);
599 if (const BlockExpr *be = dyn_cast<BlockExpr>(e)) {
600 const BlockDecl *block = be->getBlockDecl();
601 for (const auto &I : block->captures()) {
602 if (I.getVariable() == &var)
608 for (const Stmt *SubStmt : s->children())
609 // SubStmt might be null; as in missing decl or conditional of an if-stmt.
610 if (SubStmt && isAccessedBy(var, SubStmt))
616 static bool isAccessedBy(const ValueDecl *decl, const Expr *e) {
617 if (!decl) return false;
618 if (!isa<VarDecl>(decl)) return false;
619 const VarDecl *var = cast<VarDecl>(decl);
620 return isAccessedBy(*var, e);
623 static bool tryEmitARCCopyWeakInit(CodeGenFunction &CGF,
624 const LValue &destLV, const Expr *init) {
625 bool needsCast = false;
627 while (auto castExpr = dyn_cast<CastExpr>(init->IgnoreParens())) {
628 switch (castExpr->getCastKind()) {
629 // Look through casts that don't require representation changes.
632 case CK_BlockPointerToObjCPointerCast:
636 // If we find an l-value to r-value cast from a __weak variable,
637 // emit this operation as a copy or move.
638 case CK_LValueToRValue: {
639 const Expr *srcExpr = castExpr->getSubExpr();
640 if (srcExpr->getType().getObjCLifetime() != Qualifiers::OCL_Weak)
643 // Emit the source l-value.
644 LValue srcLV = CGF.EmitLValue(srcExpr);
646 // Handle a formal type change to avoid asserting.
647 auto srcAddr = srcLV.getAddress();
649 srcAddr = CGF.Builder.CreateElementBitCast(srcAddr,
650 destLV.getAddress().getElementType());
653 // If it was an l-value, use objc_copyWeak.
654 if (srcExpr->getValueKind() == VK_LValue) {
655 CGF.EmitARCCopyWeak(destLV.getAddress(), srcAddr);
657 assert(srcExpr->getValueKind() == VK_XValue);
658 CGF.EmitARCMoveWeak(destLV.getAddress(), srcAddr);
663 // Stop at anything else.
668 init = castExpr->getSubExpr();
673 static void drillIntoBlockVariable(CodeGenFunction &CGF,
675 const VarDecl *var) {
676 lvalue.setAddress(CGF.emitBlockByrefAddress(lvalue.getAddress(), var));
679 void CodeGenFunction::EmitNullabilityCheck(LValue LHS, llvm::Value *RHS,
680 SourceLocation Loc) {
681 if (!SanOpts.has(SanitizerKind::NullabilityAssign))
684 auto Nullability = LHS.getType()->getNullability(getContext());
685 if (!Nullability || *Nullability != NullabilityKind::NonNull)
688 // Check if the right hand side of the assignment is nonnull, if the left
689 // hand side must be nonnull.
690 SanitizerScope SanScope(this);
691 llvm::Value *IsNotNull = Builder.CreateIsNotNull(RHS);
692 llvm::Constant *StaticData[] = {
693 EmitCheckSourceLocation(Loc), EmitCheckTypeDescriptor(LHS.getType()),
694 llvm::ConstantInt::get(Int8Ty, 0), // The LogAlignment info is unused.
695 llvm::ConstantInt::get(Int8Ty, TCK_NonnullAssign)};
696 EmitCheck({{IsNotNull, SanitizerKind::NullabilityAssign}},
697 SanitizerHandler::TypeMismatch, StaticData, RHS);
700 void CodeGenFunction::EmitScalarInit(const Expr *init, const ValueDecl *D,
701 LValue lvalue, bool capturedByInit) {
702 Qualifiers::ObjCLifetime lifetime = lvalue.getObjCLifetime();
704 llvm::Value *value = EmitScalarExpr(init);
706 drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
707 EmitNullabilityCheck(lvalue, value, init->getExprLoc());
708 EmitStoreThroughLValue(RValue::get(value), lvalue, true);
712 if (const CXXDefaultInitExpr *DIE = dyn_cast<CXXDefaultInitExpr>(init))
713 init = DIE->getExpr();
715 // If we're emitting a value with lifetime, we have to do the
716 // initialization *before* we leave the cleanup scopes.
717 if (const ExprWithCleanups *ewc = dyn_cast<ExprWithCleanups>(init)) {
718 enterFullExpression(ewc);
719 init = ewc->getSubExpr();
721 CodeGenFunction::RunCleanupsScope Scope(*this);
723 // We have to maintain the illusion that the variable is
724 // zero-initialized. If the variable might be accessed in its
725 // initializer, zero-initialize before running the initializer, then
726 // actually perform the initialization with an assign.
727 bool accessedByInit = false;
728 if (lifetime != Qualifiers::OCL_ExplicitNone)
729 accessedByInit = (capturedByInit || isAccessedBy(D, init));
730 if (accessedByInit) {
731 LValue tempLV = lvalue;
732 // Drill down to the __block object if necessary.
733 if (capturedByInit) {
734 // We can use a simple GEP for this because it can't have been
736 tempLV.setAddress(emitBlockByrefAddress(tempLV.getAddress(),
741 auto ty = cast<llvm::PointerType>(tempLV.getAddress().getElementType());
742 llvm::Value *zero = CGM.getNullPointer(ty, tempLV.getType());
744 // If __weak, we want to use a barrier under certain conditions.
745 if (lifetime == Qualifiers::OCL_Weak)
746 EmitARCInitWeak(tempLV.getAddress(), zero);
748 // Otherwise just do a simple store.
750 EmitStoreOfScalar(zero, tempLV, /* isInitialization */ true);
753 // Emit the initializer.
754 llvm::Value *value = nullptr;
757 case Qualifiers::OCL_None:
758 llvm_unreachable("present but none");
760 case Qualifiers::OCL_ExplicitNone:
761 value = EmitARCUnsafeUnretainedScalarExpr(init);
764 case Qualifiers::OCL_Strong: {
765 value = EmitARCRetainScalarExpr(init);
769 case Qualifiers::OCL_Weak: {
770 // If it's not accessed by the initializer, try to emit the
771 // initialization with a copy or move.
772 if (!accessedByInit && tryEmitARCCopyWeakInit(*this, lvalue, init)) {
776 // No way to optimize a producing initializer into this. It's not
777 // worth optimizing for, because the value will immediately
778 // disappear in the common case.
779 value = EmitScalarExpr(init);
781 if (capturedByInit) drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
783 EmitARCStoreWeak(lvalue.getAddress(), value, /*ignored*/ true);
785 EmitARCInitWeak(lvalue.getAddress(), value);
789 case Qualifiers::OCL_Autoreleasing:
790 value = EmitARCRetainAutoreleaseScalarExpr(init);
794 if (capturedByInit) drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
796 EmitNullabilityCheck(lvalue, value, init->getExprLoc());
798 // If the variable might have been accessed by its initializer, we
799 // might have to initialize with a barrier. We have to do this for
800 // both __weak and __strong, but __weak got filtered out above.
801 if (accessedByInit && lifetime == Qualifiers::OCL_Strong) {
802 llvm::Value *oldValue = EmitLoadOfScalar(lvalue, init->getExprLoc());
803 EmitStoreOfScalar(value, lvalue, /* isInitialization */ true);
804 EmitARCRelease(oldValue, ARCImpreciseLifetime);
808 EmitStoreOfScalar(value, lvalue, /* isInitialization */ true);
811 /// canEmitInitWithFewStoresAfterMemset - Decide whether we can emit the
812 /// non-zero parts of the specified initializer with equal or fewer than
813 /// NumStores scalar stores.
814 static bool canEmitInitWithFewStoresAfterMemset(llvm::Constant *Init,
815 unsigned &NumStores) {
816 // Zero and Undef never requires any extra stores.
817 if (isa<llvm::ConstantAggregateZero>(Init) ||
818 isa<llvm::ConstantPointerNull>(Init) ||
819 isa<llvm::UndefValue>(Init))
821 if (isa<llvm::ConstantInt>(Init) || isa<llvm::ConstantFP>(Init) ||
822 isa<llvm::ConstantVector>(Init) || isa<llvm::BlockAddress>(Init) ||
823 isa<llvm::ConstantExpr>(Init))
824 return Init->isNullValue() || NumStores--;
826 // See if we can emit each element.
827 if (isa<llvm::ConstantArray>(Init) || isa<llvm::ConstantStruct>(Init)) {
828 for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
829 llvm::Constant *Elt = cast<llvm::Constant>(Init->getOperand(i));
830 if (!canEmitInitWithFewStoresAfterMemset(Elt, NumStores))
836 if (llvm::ConstantDataSequential *CDS =
837 dyn_cast<llvm::ConstantDataSequential>(Init)) {
838 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
839 llvm::Constant *Elt = CDS->getElementAsConstant(i);
840 if (!canEmitInitWithFewStoresAfterMemset(Elt, NumStores))
846 // Anything else is hard and scary.
850 /// emitStoresForInitAfterMemset - For inits that
851 /// canEmitInitWithFewStoresAfterMemset returned true for, emit the scalar
852 /// stores that would be required.
853 static void emitStoresForInitAfterMemset(llvm::Constant *Init, llvm::Value *Loc,
854 bool isVolatile, CGBuilderTy &Builder) {
855 assert(!Init->isNullValue() && !isa<llvm::UndefValue>(Init) &&
856 "called emitStoresForInitAfterMemset for zero or undef value.");
858 if (isa<llvm::ConstantInt>(Init) || isa<llvm::ConstantFP>(Init) ||
859 isa<llvm::ConstantVector>(Init) || isa<llvm::BlockAddress>(Init) ||
860 isa<llvm::ConstantExpr>(Init)) {
861 Builder.CreateDefaultAlignedStore(Init, Loc, isVolatile);
865 if (llvm::ConstantDataSequential *CDS =
866 dyn_cast<llvm::ConstantDataSequential>(Init)) {
867 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
868 llvm::Constant *Elt = CDS->getElementAsConstant(i);
870 // If necessary, get a pointer to the element and emit it.
871 if (!Elt->isNullValue() && !isa<llvm::UndefValue>(Elt))
872 emitStoresForInitAfterMemset(
873 Elt, Builder.CreateConstGEP2_32(Init->getType(), Loc, 0, i),
874 isVolatile, Builder);
879 assert((isa<llvm::ConstantStruct>(Init) || isa<llvm::ConstantArray>(Init)) &&
880 "Unknown value type!");
882 for (unsigned i = 0, e = Init->getNumOperands(); i != e; ++i) {
883 llvm::Constant *Elt = cast<llvm::Constant>(Init->getOperand(i));
885 // If necessary, get a pointer to the element and emit it.
886 if (!Elt->isNullValue() && !isa<llvm::UndefValue>(Elt))
887 emitStoresForInitAfterMemset(
888 Elt, Builder.CreateConstGEP2_32(Init->getType(), Loc, 0, i),
889 isVolatile, Builder);
893 /// shouldUseMemSetPlusStoresToInitialize - Decide whether we should use memset
894 /// plus some stores to initialize a local variable instead of using a memcpy
895 /// from a constant global. It is beneficial to use memset if the global is all
896 /// zeros, or mostly zeros and large.
897 static bool shouldUseMemSetPlusStoresToInitialize(llvm::Constant *Init,
898 uint64_t GlobalSize) {
899 // If a global is all zeros, always use a memset.
900 if (isa<llvm::ConstantAggregateZero>(Init)) return true;
902 // If a non-zero global is <= 32 bytes, always use a memcpy. If it is large,
903 // do it if it will require 6 or fewer scalar stores.
904 // TODO: Should budget depends on the size? Avoiding a large global warrants
905 // plopping in more stores.
906 unsigned StoreBudget = 6;
907 uint64_t SizeLimit = 32;
909 return GlobalSize > SizeLimit &&
910 canEmitInitWithFewStoresAfterMemset(Init, StoreBudget);
913 /// EmitAutoVarDecl - Emit code and set up an entry in LocalDeclMap for a
914 /// variable declaration with auto, register, or no storage class specifier.
915 /// These turn into simple stack objects, or GlobalValues depending on target.
916 void CodeGenFunction::EmitAutoVarDecl(const VarDecl &D) {
917 AutoVarEmission emission = EmitAutoVarAlloca(D);
918 EmitAutoVarInit(emission);
919 EmitAutoVarCleanups(emission);
922 /// Emit a lifetime.begin marker if some criteria are satisfied.
923 /// \return a pointer to the temporary size Value if a marker was emitted, null
925 llvm::Value *CodeGenFunction::EmitLifetimeStart(uint64_t Size,
927 if (!ShouldEmitLifetimeMarkers)
930 llvm::Value *SizeV = llvm::ConstantInt::get(Int64Ty, Size);
931 Addr = Builder.CreateBitCast(Addr, AllocaInt8PtrTy);
933 Builder.CreateCall(CGM.getLLVMLifetimeStartFn(), {SizeV, Addr});
934 C->setDoesNotThrow();
938 void CodeGenFunction::EmitLifetimeEnd(llvm::Value *Size, llvm::Value *Addr) {
939 Addr = Builder.CreateBitCast(Addr, AllocaInt8PtrTy);
941 Builder.CreateCall(CGM.getLLVMLifetimeEndFn(), {Size, Addr});
942 C->setDoesNotThrow();
945 /// EmitAutoVarAlloca - Emit the alloca and debug information for a
946 /// local variable. Does not emit initialization or destruction.
947 CodeGenFunction::AutoVarEmission
948 CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
949 QualType Ty = D.getType();
951 AutoVarEmission emission(D);
953 bool isByRef = D.hasAttr<BlocksAttr>();
954 emission.IsByRef = isByRef;
956 CharUnits alignment = getContext().getDeclAlign(&D);
958 // If the type is variably-modified, emit all the VLA sizes for it.
959 if (Ty->isVariablyModifiedType())
960 EmitVariablyModifiedType(Ty);
962 Address address = Address::invalid();
963 if (Ty->isConstantSizeType()) {
964 bool NRVO = getLangOpts().ElideConstructors &&
967 // If this value is an array or struct with a statically determinable
968 // constant initializer, there are optimizations we can do.
970 // TODO: We should constant-evaluate the initializer of any variable,
971 // as long as it is initialized by a constant expression. Currently,
972 // isConstantInitializer produces wrong answers for structs with
973 // reference or bitfield members, and a few other cases, and checking
974 // for POD-ness protects us from some of these.
975 if (D.getInit() && (Ty->isArrayType() || Ty->isRecordType()) &&
977 ((Ty.isPODType(getContext()) ||
978 getContext().getBaseElementType(Ty)->isObjCObjectPointerType()) &&
979 D.getInit()->isConstantInitializer(getContext(), false)))) {
981 // If the variable's a const type, and it's neither an NRVO
982 // candidate nor a __block variable and has no mutable members,
983 // emit it as a global instead.
984 // Exception is if a variable is located in non-constant address space
986 if ((!getLangOpts().OpenCL ||
987 Ty.getAddressSpace() == LangAS::opencl_constant) &&
988 (CGM.getCodeGenOpts().MergeAllConstants && !NRVO && !isByRef &&
989 CGM.isTypeConstant(Ty, true))) {
990 EmitStaticVarDecl(D, llvm::GlobalValue::InternalLinkage);
992 // Signal this condition to later callbacks.
993 emission.Addr = Address::invalid();
994 assert(emission.wasEmittedAsGlobal());
998 // Otherwise, tell the initialization code that we're in this case.
999 emission.IsConstantAggregate = true;
1002 // A normal fixed sized variable becomes an alloca in the entry block,
1003 // unless it's an NRVO variable.
1006 // The named return value optimization: allocate this variable in the
1007 // return slot, so that we can elide the copy when returning this
1008 // variable (C++0x [class.copy]p34).
1009 address = ReturnValue;
1011 if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
1012 if (!cast<CXXRecordDecl>(RecordTy->getDecl())->hasTrivialDestructor()) {
1013 // Create a flag that is used to indicate when the NRVO was applied
1014 // to this variable. Set it to zero to indicate that NRVO was not
1016 llvm::Value *Zero = Builder.getFalse();
1018 CreateTempAlloca(Zero->getType(), CharUnits::One(), "nrvo");
1019 EnsureInsertPoint();
1020 Builder.CreateStore(Zero, NRVOFlag);
1022 // Record the NRVO flag for this variable.
1023 NRVOFlags[&D] = NRVOFlag.getPointer();
1024 emission.NRVOFlag = NRVOFlag.getPointer();
1028 CharUnits allocaAlignment;
1029 llvm::Type *allocaTy;
1031 auto &byrefInfo = getBlockByrefInfo(&D);
1032 allocaTy = byrefInfo.Type;
1033 allocaAlignment = byrefInfo.ByrefAlignment;
1035 allocaTy = ConvertTypeForMem(Ty);
1036 allocaAlignment = alignment;
1039 // Create the alloca. Note that we set the name separately from
1040 // building the instruction so that it's there even in no-asserts
1042 address = CreateTempAlloca(allocaTy, allocaAlignment);
1043 address.getPointer()->setName(D.getName());
1045 // Don't emit lifetime markers for MSVC catch parameters. The lifetime of
1046 // the catch parameter starts in the catchpad instruction, and we can't
1047 // insert code in those basic blocks.
1048 bool IsMSCatchParam =
1049 D.isExceptionVariable() && getTarget().getCXXABI().isMicrosoft();
1051 // Emit a lifetime intrinsic if meaningful. There's no point in doing this
1052 // if we don't have a valid insertion point (?).
1053 if (HaveInsertPoint() && !IsMSCatchParam) {
1054 // If there's a jump into the lifetime of this variable, its lifetime
1055 // gets broken up into several regions in IR, which requires more work
1056 // to handle correctly. For now, just omit the intrinsics; this is a
1057 // rare case, and it's better to just be conservatively correct.
1060 // We have to do this in all language modes if there's a jump past the
1061 // declaration. We also have to do it in C if there's a jump to an
1062 // earlier point in the current block because non-VLA lifetimes begin as
1063 // soon as the containing block is entered, not when its variables
1064 // actually come into scope; suppressing the lifetime annotations
1065 // completely in this case is unnecessarily pessimistic, but again, this
1067 if (!Bypasses.IsBypassed(&D) &&
1068 !(!getLangOpts().CPlusPlus && hasLabelBeenSeenInCurrentScope())) {
1069 uint64_t size = CGM.getDataLayout().getTypeAllocSize(allocaTy);
1070 emission.SizeForLifetimeMarkers =
1071 EmitLifetimeStart(size, address.getPointer());
1074 assert(!emission.useLifetimeMarkers());
1078 EnsureInsertPoint();
1080 if (!DidCallStackSave) {
1083 CreateTempAlloca(Int8PtrTy, getPointerAlign(), "saved_stack");
1085 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stacksave);
1086 llvm::Value *V = Builder.CreateCall(F);
1087 Builder.CreateStore(V, Stack);
1089 DidCallStackSave = true;
1091 // Push a cleanup block and restore the stack there.
1092 // FIXME: in general circumstances, this should be an EH cleanup.
1093 pushStackRestore(NormalCleanup, Stack);
1096 llvm::Value *elementCount;
1097 QualType elementType;
1098 std::tie(elementCount, elementType) = getVLASize(Ty);
1100 llvm::Type *llvmTy = ConvertTypeForMem(elementType);
1102 // Allocate memory for the array.
1103 llvm::AllocaInst *vla = Builder.CreateAlloca(llvmTy, elementCount, "vla");
1104 vla->setAlignment(alignment.getQuantity());
1106 address = Address(vla, alignment);
1109 // Alloca always returns a pointer in alloca address space, which may
1110 // be different from the type defined by the language. For example,
1111 // in C++ the auto variables are in the default address space. Therefore
1112 // cast alloca to the expected address space when necessary.
1113 auto T = D.getType();
1114 assert(T.getAddressSpace() == LangAS::Default);
1115 if (getASTAllocaAddressSpace() != LangAS::Default) {
1116 auto *Addr = getTargetHooks().performAddrSpaceCast(
1117 *this, address.getPointer(), getASTAllocaAddressSpace(),
1118 T.getAddressSpace(),
1119 address.getElementType()->getPointerTo(
1120 getContext().getTargetAddressSpace(T.getAddressSpace())),
1122 address = Address(Addr, address.getAlignment());
1124 setAddrOfLocalVar(&D, address);
1125 emission.Addr = address;
1127 // Emit debug info for local var declaration.
1128 if (HaveInsertPoint())
1129 if (CGDebugInfo *DI = getDebugInfo()) {
1130 if (CGM.getCodeGenOpts().getDebugInfo() >=
1131 codegenoptions::LimitedDebugInfo) {
1132 DI->setLocation(D.getLocation());
1133 DI->EmitDeclareOfAutoVariable(&D, address.getPointer(), Builder);
1137 if (D.hasAttr<AnnotateAttr>())
1138 EmitVarAnnotations(&D, address.getPointer());
1140 // Make sure we call @llvm.lifetime.end.
1141 if (emission.useLifetimeMarkers())
1142 EHStack.pushCleanup<CallLifetimeEnd>(NormalEHLifetimeMarker,
1143 emission.getAllocatedAddress(),
1144 emission.getSizeForLifetimeMarkers());
1149 /// Determines whether the given __block variable is potentially
1150 /// captured by the given expression.
1151 static bool isCapturedBy(const VarDecl &var, const Expr *e) {
1152 // Skip the most common kinds of expressions that make
1153 // hierarchy-walking expensive.
1154 e = e->IgnoreParenCasts();
1156 if (const BlockExpr *be = dyn_cast<BlockExpr>(e)) {
1157 const BlockDecl *block = be->getBlockDecl();
1158 for (const auto &I : block->captures()) {
1159 if (I.getVariable() == &var)
1163 // No need to walk into the subexpressions.
1167 if (const StmtExpr *SE = dyn_cast<StmtExpr>(e)) {
1168 const CompoundStmt *CS = SE->getSubStmt();
1169 for (const auto *BI : CS->body())
1170 if (const auto *E = dyn_cast<Expr>(BI)) {
1171 if (isCapturedBy(var, E))
1174 else if (const auto *DS = dyn_cast<DeclStmt>(BI)) {
1175 // special case declarations
1176 for (const auto *I : DS->decls()) {
1177 if (const auto *VD = dyn_cast<VarDecl>((I))) {
1178 const Expr *Init = VD->getInit();
1179 if (Init && isCapturedBy(var, Init))
1185 // FIXME. Make safe assumption assuming arbitrary statements cause capturing.
1186 // Later, provide code to poke into statements for capture analysis.
1191 for (const Stmt *SubStmt : e->children())
1192 if (isCapturedBy(var, cast<Expr>(SubStmt)))
1198 /// \brief Determine whether the given initializer is trivial in the sense
1199 /// that it requires no code to be generated.
1200 bool CodeGenFunction::isTrivialInitializer(const Expr *Init) {
1204 if (const CXXConstructExpr *Construct = dyn_cast<CXXConstructExpr>(Init))
1205 if (CXXConstructorDecl *Constructor = Construct->getConstructor())
1206 if (Constructor->isTrivial() &&
1207 Constructor->isDefaultConstructor() &&
1208 !Construct->requiresZeroInitialization())
1214 void CodeGenFunction::EmitAutoVarInit(const AutoVarEmission &emission) {
1215 assert(emission.Variable && "emission was not valid!");
1217 // If this was emitted as a global constant, we're done.
1218 if (emission.wasEmittedAsGlobal()) return;
1220 const VarDecl &D = *emission.Variable;
1221 auto DL = ApplyDebugLocation::CreateDefaultArtificial(*this, D.getLocation());
1222 QualType type = D.getType();
1224 // If this local has an initializer, emit it now.
1225 const Expr *Init = D.getInit();
1227 // If we are at an unreachable point, we don't need to emit the initializer
1228 // unless it contains a label.
1229 if (!HaveInsertPoint()) {
1230 if (!Init || !ContainsLabel(Init)) return;
1231 EnsureInsertPoint();
1234 // Initialize the structure of a __block variable.
1235 if (emission.IsByRef)
1236 emitByrefStructureInit(emission);
1238 if (isTrivialInitializer(Init))
1241 // Check whether this is a byref variable that's potentially
1242 // captured and moved by its own initializer. If so, we'll need to
1243 // emit the initializer first, then copy into the variable.
1244 bool capturedByInit = emission.IsByRef && isCapturedBy(D, Init);
1247 capturedByInit ? emission.Addr : emission.getObjectAddress(*this);
1249 llvm::Constant *constant = nullptr;
1250 if (emission.IsConstantAggregate || D.isConstexpr()) {
1251 assert(!capturedByInit && "constant init contains a capturing block?");
1252 constant = CGM.EmitConstantInit(D, this);
1256 LValue lv = MakeAddrLValue(Loc, type);
1258 return EmitExprAsInit(Init, &D, lv, capturedByInit);
1261 if (!emission.IsConstantAggregate) {
1262 // For simple scalar/complex initialization, store the value directly.
1263 LValue lv = MakeAddrLValue(Loc, type);
1265 return EmitStoreThroughLValue(RValue::get(constant), lv, true);
1268 // If this is a simple aggregate initialization, we can optimize it
1270 bool isVolatile = type.isVolatileQualified();
1272 llvm::Value *SizeVal =
1273 llvm::ConstantInt::get(IntPtrTy,
1274 getContext().getTypeSizeInChars(type).getQuantity());
1276 llvm::Type *BP = Int8PtrTy;
1277 if (Loc.getType() != BP)
1278 Loc = Builder.CreateBitCast(Loc, BP);
1280 // If the initializer is all or mostly zeros, codegen with memset then do
1281 // a few stores afterward.
1282 if (shouldUseMemSetPlusStoresToInitialize(constant,
1283 CGM.getDataLayout().getTypeAllocSize(constant->getType()))) {
1284 Builder.CreateMemSet(Loc, llvm::ConstantInt::get(Int8Ty, 0), SizeVal,
1286 // Zero and undef don't require a stores.
1287 if (!constant->isNullValue() && !isa<llvm::UndefValue>(constant)) {
1288 Loc = Builder.CreateBitCast(Loc, constant->getType()->getPointerTo());
1289 emitStoresForInitAfterMemset(constant, Loc.getPointer(),
1290 isVolatile, Builder);
1293 // Otherwise, create a temporary global with the initializer then
1294 // memcpy from the global to the alloca.
1295 std::string Name = getStaticDeclName(CGM, D);
1297 if (getLangOpts().OpenCL) {
1298 AS = CGM.getContext().getTargetAddressSpace(LangAS::opencl_constant);
1299 BP = llvm::PointerType::getInt8PtrTy(getLLVMContext(), AS);
1301 llvm::GlobalVariable *GV =
1302 new llvm::GlobalVariable(CGM.getModule(), constant->getType(), true,
1303 llvm::GlobalValue::PrivateLinkage,
1304 constant, Name, nullptr,
1305 llvm::GlobalValue::NotThreadLocal, AS);
1306 GV->setAlignment(Loc.getAlignment().getQuantity());
1307 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
1309 Address SrcPtr = Address(GV, Loc.getAlignment());
1310 if (SrcPtr.getType() != BP)
1311 SrcPtr = Builder.CreateBitCast(SrcPtr, BP);
1313 Builder.CreateMemCpy(Loc, SrcPtr, SizeVal, isVolatile);
1317 /// Emit an expression as an initializer for a variable at the given
1318 /// location. The expression is not necessarily the normal
1319 /// initializer for the variable, and the address is not necessarily
1320 /// its normal location.
1322 /// \param init the initializing expression
1323 /// \param var the variable to act as if we're initializing
1324 /// \param loc the address to initialize; its type is a pointer
1325 /// to the LLVM mapping of the variable's type
1326 /// \param alignment the alignment of the address
1327 /// \param capturedByInit true if the variable is a __block variable
1328 /// whose address is potentially changed by the initializer
1329 void CodeGenFunction::EmitExprAsInit(const Expr *init, const ValueDecl *D,
1330 LValue lvalue, bool capturedByInit) {
1331 QualType type = D->getType();
1333 if (type->isReferenceType()) {
1334 RValue rvalue = EmitReferenceBindingToExpr(init);
1336 drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
1337 EmitStoreThroughLValue(rvalue, lvalue, true);
1340 switch (getEvaluationKind(type)) {
1342 EmitScalarInit(init, D, lvalue, capturedByInit);
1345 ComplexPairTy complex = EmitComplexExpr(init);
1347 drillIntoBlockVariable(*this, lvalue, cast<VarDecl>(D));
1348 EmitStoreOfComplex(complex, lvalue, /*init*/ true);
1352 if (type->isAtomicType()) {
1353 EmitAtomicInit(const_cast<Expr*>(init), lvalue);
1355 // TODO: how can we delay here if D is captured by its initializer?
1356 EmitAggExpr(init, AggValueSlot::forLValue(lvalue,
1357 AggValueSlot::IsDestructed,
1358 AggValueSlot::DoesNotNeedGCBarriers,
1359 AggValueSlot::IsNotAliased));
1363 llvm_unreachable("bad evaluation kind");
1366 /// Enter a destroy cleanup for the given local variable.
1367 void CodeGenFunction::emitAutoVarTypeCleanup(
1368 const CodeGenFunction::AutoVarEmission &emission,
1369 QualType::DestructionKind dtorKind) {
1370 assert(dtorKind != QualType::DK_none);
1372 // Note that for __block variables, we want to destroy the
1373 // original stack object, not the possibly forwarded object.
1374 Address addr = emission.getObjectAddress(*this);
1376 const VarDecl *var = emission.Variable;
1377 QualType type = var->getType();
1379 CleanupKind cleanupKind = NormalAndEHCleanup;
1380 CodeGenFunction::Destroyer *destroyer = nullptr;
1383 case QualType::DK_none:
1384 llvm_unreachable("no cleanup for trivially-destructible variable");
1386 case QualType::DK_cxx_destructor:
1387 // If there's an NRVO flag on the emission, we need a different
1389 if (emission.NRVOFlag) {
1390 assert(!type->isArrayType());
1391 CXXDestructorDecl *dtor = type->getAsCXXRecordDecl()->getDestructor();
1392 EHStack.pushCleanup<DestroyNRVOVariable>(cleanupKind, addr,
1393 dtor, emission.NRVOFlag);
1398 case QualType::DK_objc_strong_lifetime:
1399 // Suppress cleanups for pseudo-strong variables.
1400 if (var->isARCPseudoStrong()) return;
1402 // Otherwise, consider whether to use an EH cleanup or not.
1403 cleanupKind = getARCCleanupKind();
1405 // Use the imprecise destroyer by default.
1406 if (!var->hasAttr<ObjCPreciseLifetimeAttr>())
1407 destroyer = CodeGenFunction::destroyARCStrongImprecise;
1410 case QualType::DK_objc_weak_lifetime:
1414 // If we haven't chosen a more specific destroyer, use the default.
1415 if (!destroyer) destroyer = getDestroyer(dtorKind);
1417 // Use an EH cleanup in array destructors iff the destructor itself
1418 // is being pushed as an EH cleanup.
1419 bool useEHCleanup = (cleanupKind & EHCleanup);
1420 EHStack.pushCleanup<DestroyObject>(cleanupKind, addr, type, destroyer,
1424 void CodeGenFunction::EmitAutoVarCleanups(const AutoVarEmission &emission) {
1425 assert(emission.Variable && "emission was not valid!");
1427 // If this was emitted as a global constant, we're done.
1428 if (emission.wasEmittedAsGlobal()) return;
1430 // If we don't have an insertion point, we're done. Sema prevents
1431 // us from jumping into any of these scopes anyway.
1432 if (!HaveInsertPoint()) return;
1434 const VarDecl &D = *emission.Variable;
1436 // Check the type for a cleanup.
1437 if (QualType::DestructionKind dtorKind = D.getType().isDestructedType())
1438 emitAutoVarTypeCleanup(emission, dtorKind);
1440 // In GC mode, honor objc_precise_lifetime.
1441 if (getLangOpts().getGC() != LangOptions::NonGC &&
1442 D.hasAttr<ObjCPreciseLifetimeAttr>()) {
1443 EHStack.pushCleanup<ExtendGCLifetime>(NormalCleanup, &D);
1446 // Handle the cleanup attribute.
1447 if (const CleanupAttr *CA = D.getAttr<CleanupAttr>()) {
1448 const FunctionDecl *FD = CA->getFunctionDecl();
1450 llvm::Constant *F = CGM.GetAddrOfFunction(FD);
1451 assert(F && "Could not find function!");
1453 const CGFunctionInfo &Info = CGM.getTypes().arrangeFunctionDeclaration(FD);
1454 EHStack.pushCleanup<CallCleanupFunction>(NormalAndEHCleanup, F, &Info, &D);
1457 // If this is a block variable, call _Block_object_destroy
1458 // (on the unforwarded address).
1459 if (emission.IsByRef)
1460 enterByrefCleanup(emission);
1463 CodeGenFunction::Destroyer *
1464 CodeGenFunction::getDestroyer(QualType::DestructionKind kind) {
1466 case QualType::DK_none: llvm_unreachable("no destroyer for trivial dtor");
1467 case QualType::DK_cxx_destructor:
1468 return destroyCXXObject;
1469 case QualType::DK_objc_strong_lifetime:
1470 return destroyARCStrongPrecise;
1471 case QualType::DK_objc_weak_lifetime:
1472 return destroyARCWeak;
1474 llvm_unreachable("Unknown DestructionKind");
1477 /// pushEHDestroy - Push the standard destructor for the given type as
1478 /// an EH-only cleanup.
1479 void CodeGenFunction::pushEHDestroy(QualType::DestructionKind dtorKind,
1480 Address addr, QualType type) {
1481 assert(dtorKind && "cannot push destructor for trivial type");
1482 assert(needsEHCleanup(dtorKind));
1484 pushDestroy(EHCleanup, addr, type, getDestroyer(dtorKind), true);
1487 /// pushDestroy - Push the standard destructor for the given type as
1488 /// at least a normal cleanup.
1489 void CodeGenFunction::pushDestroy(QualType::DestructionKind dtorKind,
1490 Address addr, QualType type) {
1491 assert(dtorKind && "cannot push destructor for trivial type");
1493 CleanupKind cleanupKind = getCleanupKind(dtorKind);
1494 pushDestroy(cleanupKind, addr, type, getDestroyer(dtorKind),
1495 cleanupKind & EHCleanup);
1498 void CodeGenFunction::pushDestroy(CleanupKind cleanupKind, Address addr,
1499 QualType type, Destroyer *destroyer,
1500 bool useEHCleanupForArray) {
1501 pushFullExprCleanup<DestroyObject>(cleanupKind, addr, type,
1502 destroyer, useEHCleanupForArray);
1505 void CodeGenFunction::pushStackRestore(CleanupKind Kind, Address SPMem) {
1506 EHStack.pushCleanup<CallStackRestore>(Kind, SPMem);
1509 void CodeGenFunction::pushLifetimeExtendedDestroy(
1510 CleanupKind cleanupKind, Address addr, QualType type,
1511 Destroyer *destroyer, bool useEHCleanupForArray) {
1512 assert(!isInConditionalBranch() &&
1513 "performing lifetime extension from within conditional");
1515 // Push an EH-only cleanup for the object now.
1516 // FIXME: When popping normal cleanups, we need to keep this EH cleanup
1517 // around in case a temporary's destructor throws an exception.
1518 if (cleanupKind & EHCleanup)
1519 EHStack.pushCleanup<DestroyObject>(
1520 static_cast<CleanupKind>(cleanupKind & ~NormalCleanup), addr, type,
1521 destroyer, useEHCleanupForArray);
1523 // Remember that we need to push a full cleanup for the object at the
1524 // end of the full-expression.
1525 pushCleanupAfterFullExpr<DestroyObject>(
1526 cleanupKind, addr, type, destroyer, useEHCleanupForArray);
1529 /// emitDestroy - Immediately perform the destruction of the given
1532 /// \param addr - the address of the object; a type*
1533 /// \param type - the type of the object; if an array type, all
1534 /// objects are destroyed in reverse order
1535 /// \param destroyer - the function to call to destroy individual
1537 /// \param useEHCleanupForArray - whether an EH cleanup should be
1538 /// used when destroying array elements, in case one of the
1539 /// destructions throws an exception
1540 void CodeGenFunction::emitDestroy(Address addr, QualType type,
1541 Destroyer *destroyer,
1542 bool useEHCleanupForArray) {
1543 const ArrayType *arrayType = getContext().getAsArrayType(type);
1545 return destroyer(*this, addr, type);
1547 llvm::Value *length = emitArrayLength(arrayType, type, addr);
1549 CharUnits elementAlign =
1551 .alignmentOfArrayElement(getContext().getTypeSizeInChars(type));
1553 // Normally we have to check whether the array is zero-length.
1554 bool checkZeroLength = true;
1556 // But if the array length is constant, we can suppress that.
1557 if (llvm::ConstantInt *constLength = dyn_cast<llvm::ConstantInt>(length)) {
1558 // ...and if it's constant zero, we can just skip the entire thing.
1559 if (constLength->isZero()) return;
1560 checkZeroLength = false;
1563 llvm::Value *begin = addr.getPointer();
1564 llvm::Value *end = Builder.CreateInBoundsGEP(begin, length);
1565 emitArrayDestroy(begin, end, type, elementAlign, destroyer,
1566 checkZeroLength, useEHCleanupForArray);
1569 /// emitArrayDestroy - Destroys all the elements of the given array,
1570 /// beginning from last to first. The array cannot be zero-length.
1572 /// \param begin - a type* denoting the first element of the array
1573 /// \param end - a type* denoting one past the end of the array
1574 /// \param elementType - the element type of the array
1575 /// \param destroyer - the function to call to destroy elements
1576 /// \param useEHCleanup - whether to push an EH cleanup to destroy
1577 /// the remaining elements in case the destruction of a single
1579 void CodeGenFunction::emitArrayDestroy(llvm::Value *begin,
1581 QualType elementType,
1582 CharUnits elementAlign,
1583 Destroyer *destroyer,
1584 bool checkZeroLength,
1585 bool useEHCleanup) {
1586 assert(!elementType->isArrayType());
1588 // The basic structure here is a do-while loop, because we don't
1589 // need to check for the zero-element case.
1590 llvm::BasicBlock *bodyBB = createBasicBlock("arraydestroy.body");
1591 llvm::BasicBlock *doneBB = createBasicBlock("arraydestroy.done");
1593 if (checkZeroLength) {
1594 llvm::Value *isEmpty = Builder.CreateICmpEQ(begin, end,
1595 "arraydestroy.isempty");
1596 Builder.CreateCondBr(isEmpty, doneBB, bodyBB);
1599 // Enter the loop body, making that address the current address.
1600 llvm::BasicBlock *entryBB = Builder.GetInsertBlock();
1602 llvm::PHINode *elementPast =
1603 Builder.CreatePHI(begin->getType(), 2, "arraydestroy.elementPast");
1604 elementPast->addIncoming(end, entryBB);
1606 // Shift the address back by one element.
1607 llvm::Value *negativeOne = llvm::ConstantInt::get(SizeTy, -1, true);
1608 llvm::Value *element = Builder.CreateInBoundsGEP(elementPast, negativeOne,
1609 "arraydestroy.element");
1612 pushRegularPartialArrayCleanup(begin, element, elementType, elementAlign,
1615 // Perform the actual destruction there.
1616 destroyer(*this, Address(element, elementAlign), elementType);
1621 // Check whether we've reached the end.
1622 llvm::Value *done = Builder.CreateICmpEQ(element, begin, "arraydestroy.done");
1623 Builder.CreateCondBr(done, doneBB, bodyBB);
1624 elementPast->addIncoming(element, Builder.GetInsertBlock());
1630 /// Perform partial array destruction as if in an EH cleanup. Unlike
1631 /// emitArrayDestroy, the element type here may still be an array type.
1632 static void emitPartialArrayDestroy(CodeGenFunction &CGF,
1633 llvm::Value *begin, llvm::Value *end,
1634 QualType type, CharUnits elementAlign,
1635 CodeGenFunction::Destroyer *destroyer) {
1636 // If the element type is itself an array, drill down.
1637 unsigned arrayDepth = 0;
1638 while (const ArrayType *arrayType = CGF.getContext().getAsArrayType(type)) {
1639 // VLAs don't require a GEP index to walk into.
1640 if (!isa<VariableArrayType>(arrayType))
1642 type = arrayType->getElementType();
1646 llvm::Value *zero = llvm::ConstantInt::get(CGF.SizeTy, 0);
1648 SmallVector<llvm::Value*,4> gepIndices(arrayDepth+1, zero);
1649 begin = CGF.Builder.CreateInBoundsGEP(begin, gepIndices, "pad.arraybegin");
1650 end = CGF.Builder.CreateInBoundsGEP(end, gepIndices, "pad.arrayend");
1653 // Destroy the array. We don't ever need an EH cleanup because we
1654 // assume that we're in an EH cleanup ourselves, so a throwing
1655 // destructor causes an immediate terminate.
1656 CGF.emitArrayDestroy(begin, end, type, elementAlign, destroyer,
1657 /*checkZeroLength*/ true, /*useEHCleanup*/ false);
1661 /// RegularPartialArrayDestroy - a cleanup which performs a partial
1662 /// array destroy where the end pointer is regularly determined and
1663 /// does not need to be loaded from a local.
1664 class RegularPartialArrayDestroy final : public EHScopeStack::Cleanup {
1665 llvm::Value *ArrayBegin;
1666 llvm::Value *ArrayEnd;
1667 QualType ElementType;
1668 CodeGenFunction::Destroyer *Destroyer;
1669 CharUnits ElementAlign;
1671 RegularPartialArrayDestroy(llvm::Value *arrayBegin, llvm::Value *arrayEnd,
1672 QualType elementType, CharUnits elementAlign,
1673 CodeGenFunction::Destroyer *destroyer)
1674 : ArrayBegin(arrayBegin), ArrayEnd(arrayEnd),
1675 ElementType(elementType), Destroyer(destroyer),
1676 ElementAlign(elementAlign) {}
1678 void Emit(CodeGenFunction &CGF, Flags flags) override {
1679 emitPartialArrayDestroy(CGF, ArrayBegin, ArrayEnd,
1680 ElementType, ElementAlign, Destroyer);
1684 /// IrregularPartialArrayDestroy - a cleanup which performs a
1685 /// partial array destroy where the end pointer is irregularly
1686 /// determined and must be loaded from a local.
1687 class IrregularPartialArrayDestroy final : public EHScopeStack::Cleanup {
1688 llvm::Value *ArrayBegin;
1689 Address ArrayEndPointer;
1690 QualType ElementType;
1691 CodeGenFunction::Destroyer *Destroyer;
1692 CharUnits ElementAlign;
1694 IrregularPartialArrayDestroy(llvm::Value *arrayBegin,
1695 Address arrayEndPointer,
1696 QualType elementType,
1697 CharUnits elementAlign,
1698 CodeGenFunction::Destroyer *destroyer)
1699 : ArrayBegin(arrayBegin), ArrayEndPointer(arrayEndPointer),
1700 ElementType(elementType), Destroyer(destroyer),
1701 ElementAlign(elementAlign) {}
1703 void Emit(CodeGenFunction &CGF, Flags flags) override {
1704 llvm::Value *arrayEnd = CGF.Builder.CreateLoad(ArrayEndPointer);
1705 emitPartialArrayDestroy(CGF, ArrayBegin, arrayEnd,
1706 ElementType, ElementAlign, Destroyer);
1709 } // end anonymous namespace
1711 /// pushIrregularPartialArrayCleanup - Push an EH cleanup to destroy
1712 /// already-constructed elements of the given array. The cleanup
1713 /// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
1715 /// \param elementType - the immediate element type of the array;
1716 /// possibly still an array type
1717 void CodeGenFunction::pushIrregularPartialArrayCleanup(llvm::Value *arrayBegin,
1718 Address arrayEndPointer,
1719 QualType elementType,
1720 CharUnits elementAlign,
1721 Destroyer *destroyer) {
1722 pushFullExprCleanup<IrregularPartialArrayDestroy>(EHCleanup,
1723 arrayBegin, arrayEndPointer,
1724 elementType, elementAlign,
1728 /// pushRegularPartialArrayCleanup - Push an EH cleanup to destroy
1729 /// already-constructed elements of the given array. The cleanup
1730 /// may be popped with DeactivateCleanupBlock or PopCleanupBlock.
1732 /// \param elementType - the immediate element type of the array;
1733 /// possibly still an array type
1734 void CodeGenFunction::pushRegularPartialArrayCleanup(llvm::Value *arrayBegin,
1735 llvm::Value *arrayEnd,
1736 QualType elementType,
1737 CharUnits elementAlign,
1738 Destroyer *destroyer) {
1739 pushFullExprCleanup<RegularPartialArrayDestroy>(EHCleanup,
1740 arrayBegin, arrayEnd,
1741 elementType, elementAlign,
1745 /// Lazily declare the @llvm.lifetime.start intrinsic.
1746 llvm::Constant *CodeGenModule::getLLVMLifetimeStartFn() {
1747 if (LifetimeStartFn)
1748 return LifetimeStartFn;
1749 LifetimeStartFn = llvm::Intrinsic::getDeclaration(&getModule(),
1750 llvm::Intrinsic::lifetime_start, AllocaInt8PtrTy);
1751 return LifetimeStartFn;
1754 /// Lazily declare the @llvm.lifetime.end intrinsic.
1755 llvm::Constant *CodeGenModule::getLLVMLifetimeEndFn() {
1757 return LifetimeEndFn;
1758 LifetimeEndFn = llvm::Intrinsic::getDeclaration(&getModule(),
1759 llvm::Intrinsic::lifetime_end, AllocaInt8PtrTy);
1760 return LifetimeEndFn;
1764 /// A cleanup to perform a release of an object at the end of a
1765 /// function. This is used to balance out the incoming +1 of a
1766 /// ns_consumed argument when we can't reasonably do that just by
1767 /// not doing the initial retain for a __block argument.
1768 struct ConsumeARCParameter final : EHScopeStack::Cleanup {
1769 ConsumeARCParameter(llvm::Value *param,
1770 ARCPreciseLifetime_t precise)
1771 : Param(param), Precise(precise) {}
1774 ARCPreciseLifetime_t Precise;
1776 void Emit(CodeGenFunction &CGF, Flags flags) override {
1777 CGF.EmitARCRelease(Param, Precise);
1780 } // end anonymous namespace
1782 /// Emit an alloca (or GlobalValue depending on target)
1783 /// for the specified parameter and set up LocalDeclMap.
1784 void CodeGenFunction::EmitParmDecl(const VarDecl &D, ParamValue Arg,
1786 // FIXME: Why isn't ImplicitParamDecl a ParmVarDecl?
1787 assert((isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) &&
1788 "Invalid argument to EmitParmDecl");
1790 Arg.getAnyValue()->setName(D.getName());
1792 QualType Ty = D.getType();
1794 // Use better IR generation for certain implicit parameters.
1795 if (auto IPD = dyn_cast<ImplicitParamDecl>(&D)) {
1796 // The only implicit argument a block has is its literal.
1797 // We assume this is always passed directly.
1799 setBlockContextParameter(IPD, ArgNo, Arg.getDirectValue());
1803 // Apply any prologue 'this' adjustments required by the ABI. Be careful to
1804 // handle the case where 'this' is passed indirectly as part of an inalloca
1806 if (const CXXMethodDecl *MD =
1807 dyn_cast_or_null<CXXMethodDecl>(CurCodeDecl)) {
1808 if (MD->isVirtual() && IPD == CXXABIThisDecl) {
1809 llvm::Value *This = Arg.isIndirect()
1810 ? Builder.CreateLoad(Arg.getIndirectAddress())
1811 : Arg.getDirectValue();
1812 This = CGM.getCXXABI().adjustThisParameterInVirtualFunctionPrologue(
1813 *this, CurGD, This);
1814 if (Arg.isIndirect())
1815 Builder.CreateStore(This, Arg.getIndirectAddress());
1817 Arg = ParamValue::forDirect(This);
1822 Address DeclPtr = Address::invalid();
1823 bool DoStore = false;
1824 bool IsScalar = hasScalarEvaluationKind(Ty);
1825 // If we already have a pointer to the argument, reuse the input pointer.
1826 if (Arg.isIndirect()) {
1827 DeclPtr = Arg.getIndirectAddress();
1828 // If we have a prettier pointer type at this point, bitcast to that.
1829 unsigned AS = DeclPtr.getType()->getAddressSpace();
1830 llvm::Type *IRTy = ConvertTypeForMem(Ty)->getPointerTo(AS);
1831 if (DeclPtr.getType() != IRTy)
1832 DeclPtr = Builder.CreateBitCast(DeclPtr, IRTy, D.getName());
1834 // Push a destructor cleanup for this parameter if the ABI requires it.
1835 // Don't push a cleanup in a thunk for a method that will also emit a
1837 if (!IsScalar && !CurFuncIsThunk &&
1838 getTarget().getCXXABI().areArgsDestroyedLeftToRightInCallee()) {
1839 const CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
1840 if (RD && RD->hasNonTrivialDestructor())
1841 pushDestroy(QualType::DK_cxx_destructor, DeclPtr, Ty);
1844 // Otherwise, create a temporary to hold the value.
1845 DeclPtr = CreateMemTemp(Ty, getContext().getDeclAlign(&D),
1846 D.getName() + ".addr");
1850 llvm::Value *ArgVal = (DoStore ? Arg.getDirectValue() : nullptr);
1852 LValue lv = MakeAddrLValue(DeclPtr, Ty);
1854 Qualifiers qs = Ty.getQualifiers();
1855 if (Qualifiers::ObjCLifetime lt = qs.getObjCLifetime()) {
1856 // We honor __attribute__((ns_consumed)) for types with lifetime.
1857 // For __strong, it's handled by just skipping the initial retain;
1858 // otherwise we have to balance out the initial +1 with an extra
1859 // cleanup to do the release at the end of the function.
1860 bool isConsumed = D.hasAttr<NSConsumedAttr>();
1862 // 'self' is always formally __strong, but if this is not an
1863 // init method then we don't want to retain it.
1864 if (D.isARCPseudoStrong()) {
1865 const ObjCMethodDecl *method = cast<ObjCMethodDecl>(CurCodeDecl);
1866 assert(&D == method->getSelfDecl());
1867 assert(lt == Qualifiers::OCL_Strong);
1868 assert(qs.hasConst());
1869 assert(method->getMethodFamily() != OMF_init);
1871 lt = Qualifiers::OCL_ExplicitNone;
1874 if (lt == Qualifiers::OCL_Strong) {
1876 if (CGM.getCodeGenOpts().OptimizationLevel == 0) {
1877 // use objc_storeStrong(&dest, value) for retaining the
1878 // object. But first, store a null into 'dest' because
1879 // objc_storeStrong attempts to release its old value.
1880 llvm::Value *Null = CGM.EmitNullConstant(D.getType());
1881 EmitStoreOfScalar(Null, lv, /* isInitialization */ true);
1882 EmitARCStoreStrongCall(lv.getAddress(), ArgVal, true);
1886 // Don't use objc_retainBlock for block pointers, because we
1887 // don't want to Block_copy something just because we got it
1889 ArgVal = EmitARCRetainNonBlock(ArgVal);
1892 // Push the cleanup for a consumed parameter.
1894 ARCPreciseLifetime_t precise = (D.hasAttr<ObjCPreciseLifetimeAttr>()
1895 ? ARCPreciseLifetime : ARCImpreciseLifetime);
1896 EHStack.pushCleanup<ConsumeARCParameter>(getARCCleanupKind(), ArgVal,
1900 if (lt == Qualifiers::OCL_Weak) {
1901 EmitARCInitWeak(DeclPtr, ArgVal);
1902 DoStore = false; // The weak init is a store, no need to do two.
1906 // Enter the cleanup scope.
1907 EmitAutoVarWithLifetime(*this, D, DeclPtr, lt);
1911 // Store the initial value into the alloca.
1913 EmitStoreOfScalar(ArgVal, lv, /* isInitialization */ true);
1915 setAddrOfLocalVar(&D, DeclPtr);
1917 // Emit debug info for param declaration.
1918 if (CGDebugInfo *DI = getDebugInfo()) {
1919 if (CGM.getCodeGenOpts().getDebugInfo() >=
1920 codegenoptions::LimitedDebugInfo) {
1921 DI->EmitDeclareOfArgVariable(&D, DeclPtr.getPointer(), ArgNo, Builder);
1925 if (D.hasAttr<AnnotateAttr>())
1926 EmitVarAnnotations(&D, DeclPtr.getPointer());
1928 // We can only check return value nullability if all arguments to the
1929 // function satisfy their nullability preconditions. This makes it necessary
1930 // to emit null checks for args in the function body itself.
1931 if (requiresReturnValueNullabilityCheck()) {
1932 auto Nullability = Ty->getNullability(getContext());
1933 if (Nullability && *Nullability == NullabilityKind::NonNull) {
1934 SanitizerScope SanScope(this);
1935 RetValNullabilityPrecondition =
1936 Builder.CreateAnd(RetValNullabilityPrecondition,
1937 Builder.CreateIsNotNull(Arg.getAnyValue()));
1942 void CodeGenModule::EmitOMPDeclareReduction(const OMPDeclareReductionDecl *D,
1943 CodeGenFunction *CGF) {
1944 if (!LangOpts.OpenMP || (!LangOpts.EmitAllDecls && !D->isUsed()))
1946 getOpenMPRuntime().emitUserDefinedReduction(CGF, D);