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 //===----------------------------------------------------------------------===//
14 #include "CGDebugInfo.h"
15 #include "CodeGenFunction.h"
16 #include "CodeGenModule.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/CharUnits.h"
19 #include "clang/AST/Decl.h"
20 #include "clang/AST/DeclObjC.h"
21 #include "clang/Basic/SourceManager.h"
22 #include "clang/Basic/TargetInfo.h"
23 #include "clang/Frontend/CodeGenOptions.h"
24 #include "llvm/GlobalVariable.h"
25 #include "llvm/Intrinsics.h"
26 #include "llvm/Target/TargetData.h"
27 #include "llvm/Type.h"
28 using namespace clang;
29 using namespace CodeGen;
32 void CodeGenFunction::EmitDecl(const Decl &D) {
33 switch (D.getKind()) {
34 case Decl::TranslationUnit:
36 case Decl::UnresolvedUsingTypename:
37 case Decl::ClassTemplateSpecialization:
38 case Decl::ClassTemplatePartialSpecialization:
39 case Decl::TemplateTypeParm:
40 case Decl::UnresolvedUsingValue:
41 case Decl::NonTypeTemplateParm:
43 case Decl::CXXConstructor:
44 case Decl::CXXDestructor:
45 case Decl::CXXConversion:
48 case Decl::ObjCAtDefsField:
50 case Decl::ImplicitParam:
51 case Decl::ClassTemplate:
52 case Decl::FunctionTemplate:
53 case Decl::TemplateTemplateParm:
54 case Decl::ObjCMethod:
55 case Decl::ObjCCategory:
56 case Decl::ObjCProtocol:
57 case Decl::ObjCInterface:
58 case Decl::ObjCCategoryImpl:
59 case Decl::ObjCImplementation:
60 case Decl::ObjCProperty:
61 case Decl::ObjCCompatibleAlias:
62 case Decl::AccessSpec:
63 case Decl::LinkageSpec:
64 case Decl::ObjCPropertyImpl:
66 case Decl::ObjCForwardProtocol:
67 case Decl::FileScopeAsm:
69 case Decl::FriendTemplate:
72 assert(0 && "Declaration not should not be in declstmts!");
73 case Decl::Function: // void X();
74 case Decl::Record: // struct/union/class X;
75 case Decl::Enum: // enum X;
76 case Decl::EnumConstant: // enum ? { X = ? }
77 case Decl::CXXRecord: // struct/union/class X; [C++]
78 case Decl::Using: // using X; [C++]
79 case Decl::UsingShadow:
80 case Decl::UsingDirective: // using namespace X; [C++]
81 case Decl::NamespaceAlias:
82 case Decl::StaticAssert: // static_assert(X, ""); [C++0x]
83 // None of these decls require codegen support.
87 const VarDecl &VD = cast<VarDecl>(D);
88 assert(VD.isBlockVarDecl() &&
89 "Should not see file-scope variables inside a function!");
90 return EmitBlockVarDecl(VD);
93 case Decl::Typedef: { // typedef int X;
94 const TypedefDecl &TD = cast<TypedefDecl>(D);
95 QualType Ty = TD.getUnderlyingType();
97 if (Ty->isVariablyModifiedType())
103 /// EmitBlockVarDecl - This method handles emission of any variable declaration
104 /// inside a function, including static vars etc.
105 void CodeGenFunction::EmitBlockVarDecl(const VarDecl &D) {
106 if (D.hasAttr<AsmLabelAttr>())
107 CGM.ErrorUnsupported(&D, "__asm__");
109 switch (D.getStorageClass()) {
112 case VarDecl::Register:
113 return EmitLocalBlockVarDecl(D);
114 case VarDecl::Static: {
115 llvm::GlobalValue::LinkageTypes Linkage =
116 llvm::GlobalValue::InternalLinkage;
118 // If the function definition has some sort of weak linkage, its
119 // static variables should also be weak so that they get properly
120 // uniqued. We can't do this in C, though, because there's no
121 // standard way to agree on which variables are the same (i.e.
122 // there's no mangling).
123 if (getContext().getLangOptions().CPlusPlus)
124 if (llvm::GlobalValue::isWeakForLinker(CurFn->getLinkage()))
125 Linkage = CurFn->getLinkage();
127 return EmitStaticBlockVarDecl(D, Linkage);
129 case VarDecl::Extern:
130 case VarDecl::PrivateExtern:
131 // Don't emit it now, allow it to be emitted lazily on its first use.
135 assert(0 && "Unknown storage class");
138 static std::string GetStaticDeclName(CodeGenFunction &CGF, const VarDecl &D,
139 const char *Separator) {
140 CodeGenModule &CGM = CGF.CGM;
141 if (CGF.getContext().getLangOptions().CPlusPlus) {
142 llvm::StringRef Name = CGM.getMangledName(&D);
146 std::string ContextName;
147 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(CGF.CurFuncDecl)) {
148 llvm::StringRef Name = CGM.getMangledName(FD);
149 ContextName = Name.str();
150 } else if (isa<ObjCMethodDecl>(CGF.CurFuncDecl))
151 ContextName = CGF.CurFn->getName();
153 // FIXME: What about in a block??
154 assert(0 && "Unknown context for block var decl");
156 return ContextName + Separator + D.getNameAsString();
159 llvm::GlobalVariable *
160 CodeGenFunction::CreateStaticBlockVarDecl(const VarDecl &D,
161 const char *Separator,
162 llvm::GlobalValue::LinkageTypes Linkage) {
163 QualType Ty = D.getType();
164 assert(Ty->isConstantSizeType() && "VLAs can't be static");
166 std::string Name = GetStaticDeclName(*this, D, Separator);
168 const llvm::Type *LTy = CGM.getTypes().ConvertTypeForMem(Ty);
169 llvm::GlobalVariable *GV =
170 new llvm::GlobalVariable(CGM.getModule(), LTy,
171 Ty.isConstant(getContext()), Linkage,
172 CGM.EmitNullConstant(D.getType()), Name, 0,
173 D.isThreadSpecified(), Ty.getAddressSpace());
174 GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
178 /// AddInitializerToGlobalBlockVarDecl - Add the initializer for 'D' to the
179 /// global variable that has already been created for it. If the initializer
180 /// has a different type than GV does, this may free GV and return a different
181 /// one. Otherwise it just returns GV.
182 llvm::GlobalVariable *
183 CodeGenFunction::AddInitializerToGlobalBlockVarDecl(const VarDecl &D,
184 llvm::GlobalVariable *GV) {
185 llvm::Constant *Init = CGM.EmitConstantExpr(D.getInit(), D.getType(), this);
187 // If constant emission failed, then this should be a C++ static
190 if (!getContext().getLangOptions().CPlusPlus)
191 CGM.ErrorUnsupported(D.getInit(), "constant l-value expression");
193 // Since we have a static initializer, this global variable can't
195 GV->setConstant(false);
197 EmitStaticCXXBlockVarDeclInit(D, GV);
202 // The initializer may differ in type from the global. Rewrite
203 // the global to match the initializer. (We have to do this
204 // because some types, like unions, can't be completely represented
205 // in the LLVM type system.)
206 if (GV->getType() != Init->getType()) {
207 llvm::GlobalVariable *OldGV = GV;
209 GV = new llvm::GlobalVariable(CGM.getModule(), Init->getType(),
211 OldGV->getLinkage(), Init, "",
212 0, D.isThreadSpecified(),
213 D.getType().getAddressSpace());
215 // Steal the name of the old global
218 // Replace all uses of the old global with the new global
219 llvm::Constant *NewPtrForOldDecl =
220 llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
221 OldGV->replaceAllUsesWith(NewPtrForOldDecl);
223 // Erase the old global, since it is no longer used.
224 OldGV->eraseFromParent();
227 GV->setInitializer(Init);
231 void CodeGenFunction::EmitStaticBlockVarDecl(const VarDecl &D,
232 llvm::GlobalValue::LinkageTypes Linkage) {
233 llvm::Value *&DMEntry = LocalDeclMap[&D];
234 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
236 llvm::GlobalVariable *GV = CreateStaticBlockVarDecl(D, ".", Linkage);
238 // Store into LocalDeclMap before generating initializer to handle
239 // circular references.
242 // We can't have a VLA here, but we can have a pointer to a VLA,
243 // even though that doesn't really make any sense.
244 // Make sure to evaluate VLA bounds now so that we have them for later.
245 if (D.getType()->isVariablyModifiedType())
246 EmitVLASize(D.getType());
248 // If this value has an initializer, emit it.
250 GV = AddInitializerToGlobalBlockVarDecl(D, GV);
252 GV->setAlignment(getContext().getDeclAlign(&D).getQuantity());
254 // FIXME: Merge attribute handling.
255 if (const AnnotateAttr *AA = D.getAttr<AnnotateAttr>()) {
256 SourceManager &SM = CGM.getContext().getSourceManager();
257 llvm::Constant *Ann =
258 CGM.EmitAnnotateAttr(GV, AA,
259 SM.getInstantiationLineNumber(D.getLocation()));
260 CGM.AddAnnotation(Ann);
263 if (const SectionAttr *SA = D.getAttr<SectionAttr>())
264 GV->setSection(SA->getName());
266 if (D.hasAttr<UsedAttr>())
267 CGM.AddUsedGlobal(GV);
269 if (getContext().getLangOptions().CPlusPlus)
270 CGM.setStaticLocalDeclAddress(&D, GV);
272 // We may have to cast the constant because of the initializer
275 // FIXME: It is really dangerous to store this in the map; if anyone
276 // RAUW's the GV uses of this constant will be invalid.
277 const llvm::Type *LTy = CGM.getTypes().ConvertTypeForMem(D.getType());
278 const llvm::Type *LPtrTy =
279 llvm::PointerType::get(LTy, D.getType().getAddressSpace());
280 DMEntry = llvm::ConstantExpr::getBitCast(GV, LPtrTy);
282 // Emit global variable debug descriptor for static vars.
283 CGDebugInfo *DI = getDebugInfo();
285 DI->setLocation(D.getLocation());
286 DI->EmitGlobalVariable(static_cast<llvm::GlobalVariable *>(GV), &D);
290 unsigned CodeGenFunction::getByRefValueLLVMField(const ValueDecl *VD) const {
291 assert(ByRefValueInfo.count(VD) && "Did not find value!");
293 return ByRefValueInfo.find(VD)->second.second;
296 /// BuildByRefType - This routine changes a __block variable declared as T x
301 /// void *__forwarding;
304 /// void *__copy_helper; // only if needed
305 /// void *__destroy_helper; // only if needed
306 /// char padding[X]; // only if needed
310 const llvm::Type *CodeGenFunction::BuildByRefType(const ValueDecl *D) {
311 std::pair<const llvm::Type *, unsigned> &Info = ByRefValueInfo[D];
315 QualType Ty = D->getType();
317 std::vector<const llvm::Type *> Types;
319 const llvm::PointerType *Int8PtrTy = llvm::Type::getInt8PtrTy(VMContext);
321 llvm::PATypeHolder ByRefTypeHolder = llvm::OpaqueType::get(VMContext);
324 Types.push_back(Int8PtrTy);
326 // void *__forwarding;
327 Types.push_back(llvm::PointerType::getUnqual(ByRefTypeHolder));
330 Types.push_back(Int32Ty);
333 Types.push_back(Int32Ty);
335 bool HasCopyAndDispose = BlockRequiresCopying(Ty);
336 if (HasCopyAndDispose) {
337 /// void *__copy_helper;
338 Types.push_back(Int8PtrTy);
340 /// void *__destroy_helper;
341 Types.push_back(Int8PtrTy);
345 CharUnits Align = getContext().getDeclAlign(D);
346 if (Align > CharUnits::fromQuantity(Target.getPointerAlign(0) / 8)) {
347 // We have to insert padding.
349 // The struct above has 2 32-bit integers.
350 unsigned CurrentOffsetInBytes = 4 * 2;
352 // And either 2 or 4 pointers.
353 CurrentOffsetInBytes += (HasCopyAndDispose ? 4 : 2) *
354 CGM.getTargetData().getTypeAllocSize(Int8PtrTy);
357 unsigned AlignedOffsetInBytes =
358 llvm::RoundUpToAlignment(CurrentOffsetInBytes, Align.getQuantity());
360 unsigned NumPaddingBytes = AlignedOffsetInBytes - CurrentOffsetInBytes;
361 if (NumPaddingBytes > 0) {
362 const llvm::Type *Ty = llvm::Type::getInt8Ty(VMContext);
363 // FIXME: We need a sema error for alignment larger than the minimum of
364 // the maximal stack alignmint and the alignment of malloc on the system.
365 if (NumPaddingBytes > 1)
366 Ty = llvm::ArrayType::get(Ty, NumPaddingBytes);
370 // We want a packed struct.
376 Types.push_back(ConvertType(Ty));
378 const llvm::Type *T = llvm::StructType::get(VMContext, Types, Packed);
380 cast<llvm::OpaqueType>(ByRefTypeHolder.get())->refineAbstractTypeTo(T);
381 CGM.getModule().addTypeName("struct.__block_byref_" + D->getNameAsString(),
382 ByRefTypeHolder.get());
384 Info.first = ByRefTypeHolder.get();
386 Info.second = Types.size() - 1;
392 struct CallArrayDtor : EHScopeStack::LazyCleanup {
393 CallArrayDtor(const CXXDestructorDecl *Dtor,
394 const ConstantArrayType *Type,
396 : Dtor(Dtor), Type(Type), Loc(Loc) {}
398 const CXXDestructorDecl *Dtor;
399 const ConstantArrayType *Type;
402 void Emit(CodeGenFunction &CGF, bool IsForEH) {
403 QualType BaseElementTy = CGF.getContext().getBaseElementType(Type);
404 const llvm::Type *BasePtr = CGF.ConvertType(BaseElementTy);
405 BasePtr = llvm::PointerType::getUnqual(BasePtr);
406 llvm::Value *BaseAddrPtr = CGF.Builder.CreateBitCast(Loc, BasePtr);
407 CGF.EmitCXXAggrDestructorCall(Dtor, Type, BaseAddrPtr);
411 struct CallVarDtor : EHScopeStack::LazyCleanup {
412 CallVarDtor(const CXXDestructorDecl *Dtor,
413 llvm::Value *NRVOFlag,
415 : Dtor(Dtor), NRVOFlag(NRVOFlag), Loc(Loc) {}
417 const CXXDestructorDecl *Dtor;
418 llvm::Value *NRVOFlag;
421 void Emit(CodeGenFunction &CGF, bool IsForEH) {
422 // Along the exceptions path we always execute the dtor.
423 bool NRVO = !IsForEH && NRVOFlag;
425 llvm::BasicBlock *SkipDtorBB = 0;
427 // If we exited via NRVO, we skip the destructor call.
428 llvm::BasicBlock *RunDtorBB = CGF.createBasicBlock("nrvo.unused");
429 SkipDtorBB = CGF.createBasicBlock("nrvo.skipdtor");
430 llvm::Value *DidNRVO = CGF.Builder.CreateLoad(NRVOFlag, "nrvo.val");
431 CGF.Builder.CreateCondBr(DidNRVO, SkipDtorBB, RunDtorBB);
432 CGF.EmitBlock(RunDtorBB);
435 CGF.EmitCXXDestructorCall(Dtor, Dtor_Complete,
436 /*ForVirtualBase=*/false, Loc);
438 if (NRVO) CGF.EmitBlock(SkipDtorBB);
443 /// EmitLocalBlockVarDecl - Emit code and set up an entry in LocalDeclMap for a
444 /// variable declaration with auto, register, or no storage class specifier.
445 /// These turn into simple stack objects, or GlobalValues depending on target.
446 void CodeGenFunction::EmitLocalBlockVarDecl(const VarDecl &D,
447 SpecialInitFn *SpecialInit) {
448 QualType Ty = D.getType();
449 bool isByRef = D.hasAttr<BlocksAttr>();
450 bool needsDispose = false;
451 CharUnits Align = CharUnits::Zero();
452 bool IsSimpleConstantInitializer = false;
455 llvm::Value *NRVOFlag = 0;
456 llvm::Value *DeclPtr;
457 if (Ty->isConstantSizeType()) {
458 if (!Target.useGlobalsForAutomaticVariables()) {
459 NRVO = getContext().getLangOptions().ElideConstructors &&
461 // If this value is an array or struct, is POD, and if the initializer is
462 // a staticly determinable constant, try to optimize it (unless the NRVO
463 // is already optimizing this).
464 if (D.getInit() && !isByRef &&
465 (Ty->isArrayType() || Ty->isRecordType()) &&
467 D.getInit()->isConstantInitializer(getContext()) && !NRVO) {
468 // If this variable is marked 'const', emit the value as a global.
469 if (CGM.getCodeGenOpts().MergeAllConstants &&
470 Ty.isConstant(getContext())) {
471 EmitStaticBlockVarDecl(D, llvm::GlobalValue::InternalLinkage);
475 IsSimpleConstantInitializer = true;
478 // A normal fixed sized variable becomes an alloca in the entry block,
479 // unless it's an NRVO variable.
480 const llvm::Type *LTy = ConvertTypeForMem(Ty);
483 // The named return value optimization: allocate this variable in the
484 // return slot, so that we can elide the copy when returning this
485 // variable (C++0x [class.copy]p34).
486 DeclPtr = ReturnValue;
488 if (const RecordType *RecordTy = Ty->getAs<RecordType>()) {
489 if (!cast<CXXRecordDecl>(RecordTy->getDecl())->hasTrivialDestructor()) {
490 // Create a flag that is used to indicate when the NRVO was applied
491 // to this variable. Set it to zero to indicate that NRVO was not
493 const llvm::Type *BoolTy = llvm::Type::getInt1Ty(VMContext);
494 llvm::Value *Zero = llvm::ConstantInt::get(BoolTy, 0);
495 NRVOFlag = CreateTempAlloca(BoolTy, "nrvo");
496 Builder.CreateStore(Zero, NRVOFlag);
498 // Record the NRVO flag for this variable.
499 NRVOFlags[&D] = NRVOFlag;
504 LTy = BuildByRefType(&D);
506 llvm::AllocaInst *Alloc = CreateTempAlloca(LTy);
507 Alloc->setName(D.getNameAsString());
509 Align = getContext().getDeclAlign(&D);
511 Align = std::max(Align,
512 CharUnits::fromQuantity(Target.getPointerAlign(0) / 8));
513 Alloc->setAlignment(Align.getQuantity());
517 // Targets that don't support recursion emit locals as globals.
519 D.getStorageClass() == VarDecl::Register ? ".reg." : ".auto.";
520 DeclPtr = CreateStaticBlockVarDecl(D, Class,
525 // FIXME: Can this happen?
526 if (Ty->isVariablyModifiedType())
531 if (!DidCallStackSave) {
533 const llvm::Type *LTy = llvm::Type::getInt8PtrTy(VMContext);
534 llvm::Value *Stack = CreateTempAlloca(LTy, "saved_stack");
536 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stacksave);
537 llvm::Value *V = Builder.CreateCall(F);
539 Builder.CreateStore(V, Stack);
541 DidCallStackSave = true;
544 // Push a cleanup block and restore the stack there.
545 CleanupBlock scope(*this, NormalCleanup);
547 V = Builder.CreateLoad(Stack, "tmp");
548 llvm::Value *F = CGM.getIntrinsic(llvm::Intrinsic::stackrestore);
549 Builder.CreateCall(F, V);
553 // Get the element type.
554 const llvm::Type *LElemTy = ConvertTypeForMem(Ty);
555 const llvm::Type *LElemPtrTy =
556 llvm::PointerType::get(LElemTy, D.getType().getAddressSpace());
558 llvm::Value *VLASize = EmitVLASize(Ty);
560 // Allocate memory for the array.
561 llvm::AllocaInst *VLA =
562 Builder.CreateAlloca(llvm::Type::getInt8Ty(VMContext), VLASize, "vla");
563 VLA->setAlignment(getContext().getDeclAlign(&D).getQuantity());
565 DeclPtr = Builder.CreateBitCast(VLA, LElemPtrTy, "tmp");
568 llvm::Value *&DMEntry = LocalDeclMap[&D];
569 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
572 // Emit debug info for local var declaration.
573 if (CGDebugInfo *DI = getDebugInfo()) {
574 assert(HaveInsertPoint() && "Unexpected unreachable point!");
576 DI->setLocation(D.getLocation());
577 if (Target.useGlobalsForAutomaticVariables()) {
578 DI->EmitGlobalVariable(static_cast<llvm::GlobalVariable *>(DeclPtr), &D);
580 DI->EmitDeclareOfAutoVariable(&D, DeclPtr, Builder);
583 // If this local has an initializer, emit it now.
584 const Expr *Init = D.getInit();
586 // If we are at an unreachable point, we don't need to emit the initializer
587 // unless it contains a label.
588 if (!HaveInsertPoint()) {
589 if (!ContainsLabel(Init))
596 const llvm::PointerType *PtrToInt8Ty = llvm::Type::getInt8PtrTy(VMContext);
599 llvm::Value *isa_field = Builder.CreateStructGEP(DeclPtr, 0);
600 llvm::Value *forwarding_field = Builder.CreateStructGEP(DeclPtr, 1);
601 llvm::Value *flags_field = Builder.CreateStructGEP(DeclPtr, 2);
602 llvm::Value *size_field = Builder.CreateStructGEP(DeclPtr, 3);
609 if (Ty->isBlockPointerType()) {
610 flag |= BLOCK_FIELD_IS_BLOCK;
611 flags |= BLOCK_HAS_COPY_DISPOSE;
612 } else if (BlockRequiresCopying(Ty)) {
613 flag |= BLOCK_FIELD_IS_OBJECT;
614 flags |= BLOCK_HAS_COPY_DISPOSE;
617 // FIXME: Someone double check this.
618 if (Ty.isObjCGCWeak())
619 flag |= BLOCK_FIELD_IS_WEAK;
622 if (flag&BLOCK_FIELD_IS_WEAK)
624 V = llvm::ConstantInt::get(Int32Ty, isa);
625 V = Builder.CreateIntToPtr(V, PtrToInt8Ty, "isa");
626 Builder.CreateStore(V, isa_field);
628 Builder.CreateStore(DeclPtr, forwarding_field);
630 V = llvm::ConstantInt::get(Int32Ty, flags);
631 Builder.CreateStore(V, flags_field);
633 const llvm::Type *V1;
634 V1 = cast<llvm::PointerType>(DeclPtr->getType())->getElementType();
635 V = llvm::ConstantInt::get(Int32Ty,
636 CGM.GetTargetTypeStoreSize(V1).getQuantity());
637 Builder.CreateStore(V, size_field);
639 if (flags & BLOCK_HAS_COPY_DISPOSE) {
640 BlockHasCopyDispose = true;
641 llvm::Value *copy_helper = Builder.CreateStructGEP(DeclPtr, 4);
642 Builder.CreateStore(BuildbyrefCopyHelper(DeclPtr->getType(), flag,
643 Align.getQuantity()),
646 llvm::Value *destroy_helper = Builder.CreateStructGEP(DeclPtr, 5);
647 Builder.CreateStore(BuildbyrefDestroyHelper(DeclPtr->getType(), flag,
648 Align.getQuantity()),
654 SpecialInit(*this, D, DeclPtr);
656 llvm::Value *Loc = DeclPtr;
658 Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D),
659 D.getNameAsString());
662 getContext().getCanonicalType(D.getType()).isVolatileQualified();
664 // If the initializer was a simple constant initializer, we can optimize it
666 if (IsSimpleConstantInitializer) {
667 llvm::Constant *Init = CGM.EmitConstantExpr(D.getInit(),D.getType(),this);
668 assert(Init != 0 && "Wasn't a simple constant init?");
670 llvm::Value *AlignVal =
671 llvm::ConstantInt::get(Int32Ty, Align.getQuantity());
672 const llvm::Type *IntPtr =
673 llvm::IntegerType::get(VMContext, LLVMPointerWidth);
674 llvm::Value *SizeVal =
675 llvm::ConstantInt::get(IntPtr,
676 getContext().getTypeSizeInChars(Ty).getQuantity());
678 const llvm::Type *BP = llvm::Type::getInt8PtrTy(VMContext);
679 if (Loc->getType() != BP)
680 Loc = Builder.CreateBitCast(Loc, BP, "tmp");
682 llvm::Value *NotVolatile =
683 llvm::ConstantInt::get(llvm::Type::getInt1Ty(VMContext), 0);
685 // If the initializer is all zeros, codegen with memset.
686 if (isa<llvm::ConstantAggregateZero>(Init)) {
688 llvm::ConstantInt::get(llvm::Type::getInt8Ty(VMContext), 0);
689 Builder.CreateCall5(CGM.getMemSetFn(Loc->getType(), SizeVal->getType()),
690 Loc, Zero, SizeVal, AlignVal, NotVolatile);
692 // Otherwise, create a temporary global with the initializer then
693 // memcpy from the global to the alloca.
694 std::string Name = GetStaticDeclName(*this, D, ".");
695 llvm::GlobalVariable *GV =
696 new llvm::GlobalVariable(CGM.getModule(), Init->getType(), true,
697 llvm::GlobalValue::InternalLinkage,
698 Init, Name, 0, false, 0);
699 GV->setAlignment(Align.getQuantity());
701 llvm::Value *SrcPtr = GV;
702 if (SrcPtr->getType() != BP)
703 SrcPtr = Builder.CreateBitCast(SrcPtr, BP, "tmp");
705 Builder.CreateCall5(CGM.getMemCpyFn(Loc->getType(), SrcPtr->getType(),
707 Loc, SrcPtr, SizeVal, AlignVal, NotVolatile);
709 } else if (Ty->isReferenceType()) {
710 RValue RV = EmitReferenceBindingToExpr(Init, &D);
711 EmitStoreOfScalar(RV.getScalarVal(), Loc, false, Ty);
712 } else if (!hasAggregateLLVMType(Init->getType())) {
713 llvm::Value *V = EmitScalarExpr(Init);
714 EmitStoreOfScalar(V, Loc, isVolatile, D.getType());
715 } else if (Init->getType()->isAnyComplexType()) {
716 EmitComplexExprIntoAddr(Init, Loc, isVolatile);
718 EmitAggExpr(Init, Loc, isVolatile);
722 // Handle CXX destruction of variables.
724 while (const ArrayType *Array = getContext().getAsArrayType(DtorTy))
725 DtorTy = getContext().getBaseElementType(Array);
726 if (const RecordType *RT = DtorTy->getAs<RecordType>())
727 if (CXXRecordDecl *ClassDecl = dyn_cast<CXXRecordDecl>(RT->getDecl())) {
728 if (!ClassDecl->hasTrivialDestructor()) {
729 // Note: We suppress the destructor call when the corresponding NRVO
730 // flag has been set.
731 llvm::Value *Loc = DeclPtr;
733 Loc = Builder.CreateStructGEP(DeclPtr, getByRefValueLLVMField(&D),
734 D.getNameAsString());
736 const CXXDestructorDecl *D = ClassDecl->getDestructor();
737 assert(D && "EmitLocalBlockVarDecl - destructor is nul");
739 if (const ConstantArrayType *Array =
740 getContext().getAsConstantArrayType(Ty)) {
741 EHStack.pushLazyCleanup<CallArrayDtor>(NormalAndEHCleanup,
744 EHStack.pushLazyCleanup<CallVarDtor>(NormalAndEHCleanup,
750 // Handle the cleanup attribute
751 if (const CleanupAttr *CA = D.getAttr<CleanupAttr>()) {
752 const FunctionDecl *FD = CA->getFunctionDecl();
754 llvm::Constant* F = CGM.GetAddrOfFunction(FD);
755 assert(F && "Could not find function!");
757 const CGFunctionInfo &Info = CGM.getTypes().getFunctionInfo(FD);
759 // In some cases, the type of the function argument will be different from
760 // the type of the pointer. An example of this is
761 // void f(void* arg);
762 // __attribute__((cleanup(f))) void *g;
764 // To fix this we insert a bitcast here.
765 QualType ArgTy = Info.arg_begin()->type;
767 CleanupBlock CleanupScope(*this, NormalCleanup);
771 Args.push_back(std::make_pair(RValue::get(Builder.CreateBitCast(DeclPtr,
772 ConvertType(ArgTy))),
773 getContext().getPointerType(D.getType())));
774 EmitCall(Info, F, ReturnValueSlot(), Args);
778 CleanupScope.beginEHCleanup();
781 Args.push_back(std::make_pair(RValue::get(Builder.CreateBitCast(DeclPtr,
782 ConvertType(ArgTy))),
783 getContext().getPointerType(D.getType())));
784 EmitCall(Info, F, ReturnValueSlot(), Args);
788 if (needsDispose && CGM.getLangOptions().getGCMode() != LangOptions::GCOnly) {
789 CleanupBlock CleanupScope(*this, NormalCleanup);
791 llvm::Value *V = Builder.CreateStructGEP(DeclPtr, 1, "forwarding");
792 V = Builder.CreateLoad(V);
793 BuildBlockRelease(V);
795 // FIXME: Turn this on and audit the codegen
796 if (0 && Exceptions) {
797 CleanupScope.beginEHCleanup();
799 llvm::Value *V = Builder.CreateStructGEP(DeclPtr, 1, "forwarding");
800 V = Builder.CreateLoad(V);
801 BuildBlockRelease(V);
806 /// Emit an alloca (or GlobalValue depending on target)
807 /// for the specified parameter and set up LocalDeclMap.
808 void CodeGenFunction::EmitParmDecl(const VarDecl &D, llvm::Value *Arg) {
809 // FIXME: Why isn't ImplicitParamDecl a ParmVarDecl?
810 assert((isa<ParmVarDecl>(D) || isa<ImplicitParamDecl>(D)) &&
811 "Invalid argument to EmitParmDecl");
812 QualType Ty = D.getType();
813 CanQualType CTy = getContext().getCanonicalType(Ty);
815 llvm::Value *DeclPtr;
816 // If this is an aggregate or variable sized value, reuse the input pointer.
817 if (!Ty->isConstantSizeType() ||
818 CodeGenFunction::hasAggregateLLVMType(Ty)) {
821 // Otherwise, create a temporary to hold the value.
822 DeclPtr = CreateMemTemp(Ty, D.getName() + ".addr");
824 // Store the initial value into the alloca.
825 EmitStoreOfScalar(Arg, DeclPtr, CTy.isVolatileQualified(), Ty);
827 Arg->setName(D.getName());
829 llvm::Value *&DMEntry = LocalDeclMap[&D];
830 assert(DMEntry == 0 && "Decl already exists in localdeclmap!");
833 // Emit debug info for param declaration.
834 if (CGDebugInfo *DI = getDebugInfo()) {
835 DI->setLocation(D.getLocation());
836 DI->EmitDeclareOfArgVariable(&D, DeclPtr, Builder);