1 //===--- CodeGenModule.cpp - Emit LLVM Code from ASTs for a Module --------===//
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 coordinates the per-module state used while generating code.
12 //===----------------------------------------------------------------------===//
14 #include "CodeGenModule.h"
15 #include "CGDebugInfo.h"
16 #include "CodeGenFunction.h"
19 #include "CGObjCRuntime.h"
21 #include "TargetInfo.h"
22 #include "clang/Frontend/CodeGenOptions.h"
23 #include "clang/AST/ASTContext.h"
24 #include "clang/AST/CharUnits.h"
25 #include "clang/AST/DeclObjC.h"
26 #include "clang/AST/DeclCXX.h"
27 #include "clang/AST/DeclTemplate.h"
28 #include "clang/AST/RecordLayout.h"
29 #include "clang/Basic/Builtins.h"
30 #include "clang/Basic/Diagnostic.h"
31 #include "clang/Basic/SourceManager.h"
32 #include "clang/Basic/TargetInfo.h"
33 #include "clang/Basic/ConvertUTF.h"
34 #include "llvm/CallingConv.h"
35 #include "llvm/Module.h"
36 #include "llvm/Intrinsics.h"
37 #include "llvm/LLVMContext.h"
38 #include "llvm/ADT/Triple.h"
39 #include "llvm/Target/TargetData.h"
40 #include "llvm/Support/CallSite.h"
41 #include "llvm/Support/ErrorHandling.h"
42 using namespace clang;
43 using namespace CodeGen;
45 static CGCXXABI &createCXXABI(CodeGenModule &CGM) {
46 switch (CGM.getContext().Target.getCXXABI()) {
47 case CXXABI_ARM: return *CreateARMCXXABI(CGM);
48 case CXXABI_Itanium: return *CreateItaniumCXXABI(CGM);
49 case CXXABI_Microsoft: return *CreateMicrosoftCXXABI(CGM);
52 llvm_unreachable("invalid C++ ABI kind");
53 return *CreateItaniumCXXABI(CGM);
57 CodeGenModule::CodeGenModule(ASTContext &C, const CodeGenOptions &CGO,
58 llvm::Module &M, const llvm::TargetData &TD,
60 : BlockModule(C, M, TD, Types, *this), Context(C),
61 Features(C.getLangOptions()), CodeGenOpts(CGO), TheModule(M),
62 TheTargetData(TD), TheTargetCodeGenInfo(0), Diags(diags),
63 ABI(createCXXABI(*this)),
64 Types(C, M, TD, getTargetCodeGenInfo().getABIInfo(), ABI),
65 VTables(*this), Runtime(0),
66 CFConstantStringClassRef(0), NSConstantStringClassRef(0),
67 VMContext(M.getContext()),
68 NSConcreteGlobalBlockDecl(0), NSConcreteStackBlockDecl(0),
69 NSConcreteGlobalBlock(0), NSConcreteStackBlock(0),
70 BlockObjectAssignDecl(0), BlockObjectDisposeDecl(0),
71 BlockObjectAssign(0), BlockObjectDispose(0){
75 else if (!Features.NeXTRuntime)
76 Runtime = CreateGNUObjCRuntime(*this);
77 else if (Features.ObjCNonFragileABI)
78 Runtime = CreateMacNonFragileABIObjCRuntime(*this);
80 Runtime = CreateMacObjCRuntime(*this);
82 // If debug info generation is enabled, create the CGDebugInfo object.
83 DebugInfo = CodeGenOpts.DebugInfo ? new CGDebugInfo(*this) : 0;
86 CodeGenModule::~CodeGenModule() {
92 void CodeGenModule::createObjCRuntime() {
93 if (!Features.NeXTRuntime)
94 Runtime = CreateGNUObjCRuntime(*this);
95 else if (Features.ObjCNonFragileABI)
96 Runtime = CreateMacNonFragileABIObjCRuntime(*this);
98 Runtime = CreateMacObjCRuntime(*this);
101 void CodeGenModule::Release() {
103 EmitCXXGlobalInitFunc();
104 EmitCXXGlobalDtorFunc();
106 if (llvm::Function *ObjCInitFunction = Runtime->ModuleInitFunction())
107 AddGlobalCtor(ObjCInitFunction);
108 EmitCtorList(GlobalCtors, "llvm.global_ctors");
109 EmitCtorList(GlobalDtors, "llvm.global_dtors");
113 if (getCodeGenOpts().EmitDeclMetadata)
117 bool CodeGenModule::isTargetDarwin() const {
118 return getContext().Target.getTriple().getOS() == llvm::Triple::Darwin;
121 /// ErrorUnsupported - Print out an error that codegen doesn't support the
122 /// specified stmt yet.
123 void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type,
125 if (OmitOnError && getDiags().hasErrorOccurred())
127 unsigned DiagID = getDiags().getCustomDiagID(Diagnostic::Error,
128 "cannot compile this %0 yet");
129 std::string Msg = Type;
130 getDiags().Report(Context.getFullLoc(S->getLocStart()), DiagID)
131 << Msg << S->getSourceRange();
134 /// ErrorUnsupported - Print out an error that codegen doesn't support the
135 /// specified decl yet.
136 void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type,
138 if (OmitOnError && getDiags().hasErrorOccurred())
140 unsigned DiagID = getDiags().getCustomDiagID(Diagnostic::Error,
141 "cannot compile this %0 yet");
142 std::string Msg = Type;
143 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg;
146 LangOptions::VisibilityMode
147 CodeGenModule::getDeclVisibilityMode(const Decl *D) const {
148 if (const VarDecl *VD = dyn_cast<VarDecl>(D))
149 if (VD->getStorageClass() == SC_PrivateExtern)
150 return LangOptions::Hidden;
152 if (const VisibilityAttr *attr = D->getAttr<VisibilityAttr>()) {
153 switch (attr->getVisibility()) {
154 default: assert(0 && "Unknown visibility!");
155 case VisibilityAttr::Default:
156 return LangOptions::Default;
157 case VisibilityAttr::Hidden:
158 return LangOptions::Hidden;
159 case VisibilityAttr::Protected:
160 return LangOptions::Protected;
164 if (getLangOptions().CPlusPlus) {
165 // Entities subject to an explicit instantiation declaration get default
167 if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) {
168 if (Function->getTemplateSpecializationKind()
169 == TSK_ExplicitInstantiationDeclaration)
170 return LangOptions::Default;
171 } else if (const ClassTemplateSpecializationDecl *ClassSpec
172 = dyn_cast<ClassTemplateSpecializationDecl>(D)) {
173 if (ClassSpec->getSpecializationKind()
174 == TSK_ExplicitInstantiationDeclaration)
175 return LangOptions::Default;
176 } else if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D)) {
177 if (Record->getTemplateSpecializationKind()
178 == TSK_ExplicitInstantiationDeclaration)
179 return LangOptions::Default;
180 } else if (const VarDecl *Var = dyn_cast<VarDecl>(D)) {
181 if (Var->isStaticDataMember() &&
182 (Var->getTemplateSpecializationKind()
183 == TSK_ExplicitInstantiationDeclaration))
184 return LangOptions::Default;
187 // If -fvisibility-inlines-hidden was provided, then inline C++ member
188 // functions get "hidden" visibility by default.
189 if (getLangOptions().InlineVisibilityHidden)
190 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
191 if (Method->isInlined())
192 return LangOptions::Hidden;
195 // If this decl is contained in a class, it should have the same visibility
196 // as the parent class.
197 if (const DeclContext *DC = D->getDeclContext())
199 return getDeclVisibilityMode(cast<Decl>(DC));
201 return getLangOptions().getVisibilityMode();
204 void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV,
205 const Decl *D) const {
206 // Internal definitions always have default visibility.
207 if (GV->hasLocalLinkage()) {
208 GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
212 switch (getDeclVisibilityMode(D)) {
213 default: assert(0 && "Unknown visibility!");
214 case LangOptions::Default:
215 return GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
216 case LangOptions::Hidden:
217 return GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
218 case LangOptions::Protected:
219 return GV->setVisibility(llvm::GlobalValue::ProtectedVisibility);
223 /// Set the symbol visibility of type information (vtable and RTTI)
224 /// associated with the given type.
225 void CodeGenModule::setTypeVisibility(llvm::GlobalValue *GV,
226 const CXXRecordDecl *RD,
227 bool IsForRTTI) const {
228 setGlobalVisibility(GV, RD);
230 if (!CodeGenOpts.HiddenWeakVTables)
233 // We want to drop the visibility to hidden for weak type symbols.
234 // This isn't possible if there might be unresolved references
235 // elsewhere that rely on this symbol being visible.
237 // This should be kept roughly in sync with setThunkVisibility
241 if (GV->getLinkage() != llvm::GlobalVariable::WeakODRLinkage ||
242 GV->getVisibility() != llvm::GlobalVariable::DefaultVisibility)
245 // Don't override an explicit visibility attribute.
246 if (RD->hasAttr<VisibilityAttr>())
249 switch (RD->getTemplateSpecializationKind()) {
250 // We have to disable the optimization if this is an EI definition
251 // because there might be EI declarations in other shared objects.
252 case TSK_ExplicitInstantiationDefinition:
253 case TSK_ExplicitInstantiationDeclaration:
256 // Every use of a non-template class's type information has to emit it.
260 // In theory, implicit instantiations can ignore the possibility of
261 // an explicit instantiation declaration because there necessarily
262 // must be an EI definition somewhere with default visibility. In
263 // practice, it's possible to have an explicit instantiation for
264 // an arbitrary template class, and linkers aren't necessarily able
265 // to deal with mixed-visibility symbols.
266 case TSK_ExplicitSpecialization:
267 case TSK_ImplicitInstantiation:
268 if (!CodeGenOpts.HiddenWeakTemplateVTables)
273 // If there's a key function, there may be translation units
274 // that don't have the key function's definition. But ignore
275 // this if we're emitting RTTI under -fno-rtti.
276 if (!IsForRTTI || Features.RTTI)
277 if (Context.getKeyFunction(RD))
280 // Otherwise, drop the visibility to hidden.
281 GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
284 llvm::StringRef CodeGenModule::getMangledName(GlobalDecl GD) {
285 const NamedDecl *ND = cast<NamedDecl>(GD.getDecl());
287 llvm::StringRef &Str = MangledDeclNames[GD.getCanonicalDecl()];
291 if (!getCXXABI().getMangleContext().shouldMangleDeclName(ND)) {
292 IdentifierInfo *II = ND->getIdentifier();
293 assert(II && "Attempt to mangle unnamed decl.");
299 llvm::SmallString<256> Buffer;
300 if (const CXXConstructorDecl *D = dyn_cast<CXXConstructorDecl>(ND))
301 getCXXABI().getMangleContext().mangleCXXCtor(D, GD.getCtorType(), Buffer);
302 else if (const CXXDestructorDecl *D = dyn_cast<CXXDestructorDecl>(ND))
303 getCXXABI().getMangleContext().mangleCXXDtor(D, GD.getDtorType(), Buffer);
304 else if (const BlockDecl *BD = dyn_cast<BlockDecl>(ND))
305 getCXXABI().getMangleContext().mangleBlock(GD, BD, Buffer);
307 getCXXABI().getMangleContext().mangleName(ND, Buffer);
309 // Allocate space for the mangled name.
310 size_t Length = Buffer.size();
311 char *Name = MangledNamesAllocator.Allocate<char>(Length);
312 std::copy(Buffer.begin(), Buffer.end(), Name);
314 Str = llvm::StringRef(Name, Length);
319 void CodeGenModule::getMangledName(GlobalDecl GD, MangleBuffer &Buffer,
320 const BlockDecl *BD) {
321 getCXXABI().getMangleContext().mangleBlock(GD, BD, Buffer.getBuffer());
324 llvm::GlobalValue *CodeGenModule::GetGlobalValue(llvm::StringRef Name) {
325 return getModule().getNamedValue(Name);
328 /// AddGlobalCtor - Add a function to the list that will be called before
330 void CodeGenModule::AddGlobalCtor(llvm::Function * Ctor, int Priority) {
331 // FIXME: Type coercion of void()* types.
332 GlobalCtors.push_back(std::make_pair(Ctor, Priority));
335 /// AddGlobalDtor - Add a function to the list that will be called
336 /// when the module is unloaded.
337 void CodeGenModule::AddGlobalDtor(llvm::Function * Dtor, int Priority) {
338 // FIXME: Type coercion of void()* types.
339 GlobalDtors.push_back(std::make_pair(Dtor, Priority));
342 void CodeGenModule::EmitCtorList(const CtorList &Fns, const char *GlobalName) {
343 // Ctor function type is void()*.
344 llvm::FunctionType* CtorFTy =
345 llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext),
346 std::vector<const llvm::Type*>(),
348 llvm::Type *CtorPFTy = llvm::PointerType::getUnqual(CtorFTy);
350 // Get the type of a ctor entry, { i32, void ()* }.
351 llvm::StructType* CtorStructTy =
352 llvm::StructType::get(VMContext, llvm::Type::getInt32Ty(VMContext),
353 llvm::PointerType::getUnqual(CtorFTy), NULL);
355 // Construct the constructor and destructor arrays.
356 std::vector<llvm::Constant*> Ctors;
357 for (CtorList::const_iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) {
358 std::vector<llvm::Constant*> S;
359 S.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext),
361 S.push_back(llvm::ConstantExpr::getBitCast(I->first, CtorPFTy));
362 Ctors.push_back(llvm::ConstantStruct::get(CtorStructTy, S));
365 if (!Ctors.empty()) {
366 llvm::ArrayType *AT = llvm::ArrayType::get(CtorStructTy, Ctors.size());
367 new llvm::GlobalVariable(TheModule, AT, false,
368 llvm::GlobalValue::AppendingLinkage,
369 llvm::ConstantArray::get(AT, Ctors),
374 void CodeGenModule::EmitAnnotations() {
375 if (Annotations.empty())
378 // Create a new global variable for the ConstantStruct in the Module.
379 llvm::Constant *Array =
380 llvm::ConstantArray::get(llvm::ArrayType::get(Annotations[0]->getType(),
383 llvm::GlobalValue *gv =
384 new llvm::GlobalVariable(TheModule, Array->getType(), false,
385 llvm::GlobalValue::AppendingLinkage, Array,
386 "llvm.global.annotations");
387 gv->setSection("llvm.metadata");
390 llvm::GlobalValue::LinkageTypes
391 CodeGenModule::getFunctionLinkage(const FunctionDecl *D) {
392 GVALinkage Linkage = getContext().GetGVALinkageForFunction(D);
394 if (Linkage == GVA_Internal)
395 return llvm::Function::InternalLinkage;
397 if (D->hasAttr<DLLExportAttr>())
398 return llvm::Function::DLLExportLinkage;
400 if (D->hasAttr<WeakAttr>())
401 return llvm::Function::WeakAnyLinkage;
403 // In C99 mode, 'inline' functions are guaranteed to have a strong
404 // definition somewhere else, so we can use available_externally linkage.
405 if (Linkage == GVA_C99Inline)
406 return llvm::Function::AvailableExternallyLinkage;
408 // In C++, the compiler has to emit a definition in every translation unit
409 // that references the function. We should use linkonce_odr because
410 // a) if all references in this translation unit are optimized away, we
411 // don't need to codegen it. b) if the function persists, it needs to be
412 // merged with other definitions. c) C++ has the ODR, so we know the
413 // definition is dependable.
414 if (Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
415 return llvm::Function::LinkOnceODRLinkage;
417 // An explicit instantiation of a template has weak linkage, since
418 // explicit instantiations can occur in multiple translation units
419 // and must all be equivalent. However, we are not allowed to
420 // throw away these explicit instantiations.
421 if (Linkage == GVA_ExplicitTemplateInstantiation)
422 return llvm::Function::WeakODRLinkage;
424 // Otherwise, we have strong external linkage.
425 assert(Linkage == GVA_StrongExternal);
426 return llvm::Function::ExternalLinkage;
430 /// SetFunctionDefinitionAttributes - Set attributes for a global.
432 /// FIXME: This is currently only done for aliases and functions, but not for
433 /// variables (these details are set in EmitGlobalVarDefinition for variables).
434 void CodeGenModule::SetFunctionDefinitionAttributes(const FunctionDecl *D,
435 llvm::GlobalValue *GV) {
436 SetCommonAttributes(D, GV);
439 void CodeGenModule::SetLLVMFunctionAttributes(const Decl *D,
440 const CGFunctionInfo &Info,
442 unsigned CallingConv;
443 AttributeListType AttributeList;
444 ConstructAttributeList(Info, D, AttributeList, CallingConv);
445 F->setAttributes(llvm::AttrListPtr::get(AttributeList.begin(),
446 AttributeList.size()));
447 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
450 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
452 if (!Features.Exceptions && !Features.ObjCNonFragileABI)
453 F->addFnAttr(llvm::Attribute::NoUnwind);
455 if (D->hasAttr<AlwaysInlineAttr>())
456 F->addFnAttr(llvm::Attribute::AlwaysInline);
458 if (D->hasAttr<NoInlineAttr>())
459 F->addFnAttr(llvm::Attribute::NoInline);
461 if (Features.getStackProtectorMode() == LangOptions::SSPOn)
462 F->addFnAttr(llvm::Attribute::StackProtect);
463 else if (Features.getStackProtectorMode() == LangOptions::SSPReq)
464 F->addFnAttr(llvm::Attribute::StackProtectReq);
466 unsigned alignment = D->getMaxAlignment() / Context.getCharWidth();
468 F->setAlignment(alignment);
470 // C++ ABI requires 2-byte alignment for member functions.
471 if (F->getAlignment() < 2 && isa<CXXMethodDecl>(D))
475 void CodeGenModule::SetCommonAttributes(const Decl *D,
476 llvm::GlobalValue *GV) {
477 setGlobalVisibility(GV, D);
479 if (D->hasAttr<UsedAttr>())
482 if (const SectionAttr *SA = D->getAttr<SectionAttr>())
483 GV->setSection(SA->getName());
485 getTargetCodeGenInfo().SetTargetAttributes(D, GV, *this);
488 void CodeGenModule::SetInternalFunctionAttributes(const Decl *D,
490 const CGFunctionInfo &FI) {
491 SetLLVMFunctionAttributes(D, FI, F);
492 SetLLVMFunctionAttributesForDefinition(D, F);
494 F->setLinkage(llvm::Function::InternalLinkage);
496 SetCommonAttributes(D, F);
499 void CodeGenModule::SetFunctionAttributes(GlobalDecl GD,
501 bool IsIncompleteFunction) {
502 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
504 if (!IsIncompleteFunction)
505 SetLLVMFunctionAttributes(FD, getTypes().getFunctionInfo(GD), F);
507 // Only a few attributes are set on declarations; these may later be
508 // overridden by a definition.
510 if (FD->hasAttr<DLLImportAttr>()) {
511 F->setLinkage(llvm::Function::DLLImportLinkage);
512 } else if (FD->hasAttr<WeakAttr>() ||
513 FD->hasAttr<WeakImportAttr>()) {
514 // "extern_weak" is overloaded in LLVM; we probably should have
515 // separate linkage types for this.
516 F->setLinkage(llvm::Function::ExternalWeakLinkage);
518 F->setLinkage(llvm::Function::ExternalLinkage);
521 if (const SectionAttr *SA = FD->getAttr<SectionAttr>())
522 F->setSection(SA->getName());
525 void CodeGenModule::AddUsedGlobal(llvm::GlobalValue *GV) {
526 assert(!GV->isDeclaration() &&
527 "Only globals with definition can force usage.");
528 LLVMUsed.push_back(GV);
531 void CodeGenModule::EmitLLVMUsed() {
532 // Don't create llvm.used if there is no need.
533 if (LLVMUsed.empty())
536 const llvm::Type *i8PTy = llvm::Type::getInt8PtrTy(VMContext);
538 // Convert LLVMUsed to what ConstantArray needs.
539 std::vector<llvm::Constant*> UsedArray;
540 UsedArray.resize(LLVMUsed.size());
541 for (unsigned i = 0, e = LLVMUsed.size(); i != e; ++i) {
543 llvm::ConstantExpr::getBitCast(cast<llvm::Constant>(&*LLVMUsed[i]),
547 if (UsedArray.empty())
549 llvm::ArrayType *ATy = llvm::ArrayType::get(i8PTy, UsedArray.size());
551 llvm::GlobalVariable *GV =
552 new llvm::GlobalVariable(getModule(), ATy, false,
553 llvm::GlobalValue::AppendingLinkage,
554 llvm::ConstantArray::get(ATy, UsedArray),
557 GV->setSection("llvm.metadata");
560 void CodeGenModule::EmitDeferred() {
561 // Emit code for any potentially referenced deferred decls. Since a
562 // previously unused static decl may become used during the generation of code
563 // for a static function, iterate until no changes are made.
565 while (!DeferredDeclsToEmit.empty() || !DeferredVTables.empty()) {
566 if (!DeferredVTables.empty()) {
567 const CXXRecordDecl *RD = DeferredVTables.back();
568 DeferredVTables.pop_back();
569 getVTables().GenerateClassData(getVTableLinkage(RD), RD);
573 GlobalDecl D = DeferredDeclsToEmit.back();
574 DeferredDeclsToEmit.pop_back();
576 // Check to see if we've already emitted this. This is necessary
577 // for a couple of reasons: first, decls can end up in the
578 // deferred-decls queue multiple times, and second, decls can end
579 // up with definitions in unusual ways (e.g. by an extern inline
580 // function acquiring a strong function redefinition). Just
581 // ignore these cases.
583 // TODO: That said, looking this up multiple times is very wasteful.
584 llvm::StringRef Name = getMangledName(D);
585 llvm::GlobalValue *CGRef = GetGlobalValue(Name);
586 assert(CGRef && "Deferred decl wasn't referenced?");
588 if (!CGRef->isDeclaration())
591 // GlobalAlias::isDeclaration() defers to the aliasee, but for our
592 // purposes an alias counts as a definition.
593 if (isa<llvm::GlobalAlias>(CGRef))
596 // Otherwise, emit the definition and move on to the next one.
597 EmitGlobalDefinition(D);
601 /// EmitAnnotateAttr - Generate the llvm::ConstantStruct which contains the
602 /// annotation information for a given GlobalValue. The annotation struct is
603 /// {i8 *, i8 *, i8 *, i32}. The first field is a constant expression, the
604 /// GlobalValue being annotated. The second field is the constant string
605 /// created from the AnnotateAttr's annotation. The third field is a constant
606 /// string containing the name of the translation unit. The fourth field is
607 /// the line number in the file of the annotated value declaration.
609 /// FIXME: this does not unique the annotation string constants, as llvm-gcc
612 llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV,
613 const AnnotateAttr *AA,
615 llvm::Module *M = &getModule();
617 // get [N x i8] constants for the annotation string, and the filename string
618 // which are the 2nd and 3rd elements of the global annotation structure.
619 const llvm::Type *SBP = llvm::Type::getInt8PtrTy(VMContext);
620 llvm::Constant *anno = llvm::ConstantArray::get(VMContext,
621 AA->getAnnotation(), true);
622 llvm::Constant *unit = llvm::ConstantArray::get(VMContext,
623 M->getModuleIdentifier(),
626 // Get the two global values corresponding to the ConstantArrays we just
627 // created to hold the bytes of the strings.
628 llvm::GlobalValue *annoGV =
629 new llvm::GlobalVariable(*M, anno->getType(), false,
630 llvm::GlobalValue::PrivateLinkage, anno,
632 // translation unit name string, emitted into the llvm.metadata section.
633 llvm::GlobalValue *unitGV =
634 new llvm::GlobalVariable(*M, unit->getType(), false,
635 llvm::GlobalValue::PrivateLinkage, unit,
638 // Create the ConstantStruct for the global annotation.
639 llvm::Constant *Fields[4] = {
640 llvm::ConstantExpr::getBitCast(GV, SBP),
641 llvm::ConstantExpr::getBitCast(annoGV, SBP),
642 llvm::ConstantExpr::getBitCast(unitGV, SBP),
643 llvm::ConstantInt::get(llvm::Type::getInt32Ty(VMContext), LineNo)
645 return llvm::ConstantStruct::get(VMContext, Fields, 4, false);
648 bool CodeGenModule::MayDeferGeneration(const ValueDecl *Global) {
649 // Never defer when EmitAllDecls is specified.
650 if (Features.EmitAllDecls)
653 return !getContext().DeclMustBeEmitted(Global);
656 llvm::Constant *CodeGenModule::GetWeakRefReference(const ValueDecl *VD) {
657 const AliasAttr *AA = VD->getAttr<AliasAttr>();
658 assert(AA && "No alias?");
660 const llvm::Type *DeclTy = getTypes().ConvertTypeForMem(VD->getType());
662 // See if there is already something with the target's name in the module.
663 llvm::GlobalValue *Entry = GetGlobalValue(AA->getAliasee());
665 llvm::Constant *Aliasee;
666 if (isa<llvm::FunctionType>(DeclTy))
667 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GlobalDecl());
669 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(),
670 llvm::PointerType::getUnqual(DeclTy), 0);
672 llvm::GlobalValue* F = cast<llvm::GlobalValue>(Aliasee);
673 F->setLinkage(llvm::Function::ExternalWeakLinkage);
674 WeakRefReferences.insert(F);
680 void CodeGenModule::EmitGlobal(GlobalDecl GD) {
681 const ValueDecl *Global = cast<ValueDecl>(GD.getDecl());
683 // Weak references don't produce any output by themselves.
684 if (Global->hasAttr<WeakRefAttr>())
687 // If this is an alias definition (which otherwise looks like a declaration)
689 if (Global->hasAttr<AliasAttr>())
690 return EmitAliasDefinition(GD);
692 // Ignore declarations, they will be emitted on their first use.
693 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Global)) {
694 if (FD->getIdentifier()) {
695 llvm::StringRef Name = FD->getName();
696 if (Name == "_Block_object_assign") {
697 BlockObjectAssignDecl = FD;
698 } else if (Name == "_Block_object_dispose") {
699 BlockObjectDisposeDecl = FD;
703 // Forward declarations are emitted lazily on first use.
704 if (!FD->isThisDeclarationADefinition())
707 const VarDecl *VD = cast<VarDecl>(Global);
708 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global.");
710 if (VD->getIdentifier()) {
711 llvm::StringRef Name = VD->getName();
712 if (Name == "_NSConcreteGlobalBlock") {
713 NSConcreteGlobalBlockDecl = VD;
714 } else if (Name == "_NSConcreteStackBlock") {
715 NSConcreteStackBlockDecl = VD;
720 if (VD->isThisDeclarationADefinition() != VarDecl::Definition)
724 // Defer code generation when possible if this is a static definition, inline
725 // function etc. These we only want to emit if they are used.
726 if (!MayDeferGeneration(Global)) {
727 // Emit the definition if it can't be deferred.
728 EmitGlobalDefinition(GD);
732 // If we're deferring emission of a C++ variable with an
733 // initializer, remember the order in which it appeared in the file.
734 if (getLangOptions().CPlusPlus && isa<VarDecl>(Global) &&
735 cast<VarDecl>(Global)->hasInit()) {
736 DelayedCXXInitPosition[Global] = CXXGlobalInits.size();
737 CXXGlobalInits.push_back(0);
740 // If the value has already been used, add it directly to the
741 // DeferredDeclsToEmit list.
742 llvm::StringRef MangledName = getMangledName(GD);
743 if (GetGlobalValue(MangledName))
744 DeferredDeclsToEmit.push_back(GD);
746 // Otherwise, remember that we saw a deferred decl with this name. The
747 // first use of the mangled name will cause it to move into
748 // DeferredDeclsToEmit.
749 DeferredDecls[MangledName] = GD;
753 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD) {
754 const ValueDecl *D = cast<ValueDecl>(GD.getDecl());
756 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(),
757 Context.getSourceManager(),
758 "Generating code for declaration");
760 if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) {
761 // At -O0, don't generate IR for functions with available_externally
763 if (CodeGenOpts.OptimizationLevel == 0 &&
764 !Function->hasAttr<AlwaysInlineAttr>() &&
765 getFunctionLinkage(Function)
766 == llvm::Function::AvailableExternallyLinkage)
769 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
770 if (Method->isVirtual())
771 getVTables().EmitThunks(GD);
773 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(Method))
774 return EmitCXXConstructor(CD, GD.getCtorType());
776 if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(Method))
777 return EmitCXXDestructor(DD, GD.getDtorType());
780 return EmitGlobalFunctionDefinition(GD);
783 if (const VarDecl *VD = dyn_cast<VarDecl>(D))
784 return EmitGlobalVarDefinition(VD);
786 assert(0 && "Invalid argument to EmitGlobalDefinition()");
789 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the
790 /// module, create and return an llvm Function with the specified type. If there
791 /// is something in the module with the specified name, return it potentially
792 /// bitcasted to the right type.
794 /// If D is non-null, it specifies a decl that correspond to this. This is used
795 /// to set the attributes on the function when it is first created.
797 CodeGenModule::GetOrCreateLLVMFunction(llvm::StringRef MangledName,
798 const llvm::Type *Ty,
800 // Lookup the entry, lazily creating it if necessary.
801 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
803 if (WeakRefReferences.count(Entry)) {
804 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D.getDecl());
805 if (FD && !FD->hasAttr<WeakAttr>())
806 Entry->setLinkage(llvm::Function::ExternalLinkage);
808 WeakRefReferences.erase(Entry);
811 if (Entry->getType()->getElementType() == Ty)
814 // Make sure the result is of the correct type.
815 const llvm::Type *PTy = llvm::PointerType::getUnqual(Ty);
816 return llvm::ConstantExpr::getBitCast(Entry, PTy);
819 // This function doesn't have a complete type (for example, the return
820 // type is an incomplete struct). Use a fake type instead, and make
821 // sure not to try to set attributes.
822 bool IsIncompleteFunction = false;
824 const llvm::FunctionType *FTy;
825 if (isa<llvm::FunctionType>(Ty)) {
826 FTy = cast<llvm::FunctionType>(Ty);
828 FTy = llvm::FunctionType::get(llvm::Type::getVoidTy(VMContext),
829 std::vector<const llvm::Type*>(), false);
830 IsIncompleteFunction = true;
833 llvm::Function *F = llvm::Function::Create(FTy,
834 llvm::Function::ExternalLinkage,
835 MangledName, &getModule());
836 assert(F->getName() == MangledName && "name was uniqued!");
838 SetFunctionAttributes(D, F, IsIncompleteFunction);
840 // This is the first use or definition of a mangled name. If there is a
841 // deferred decl with this name, remember that we need to emit it at the end
843 llvm::StringMap<GlobalDecl>::iterator DDI = DeferredDecls.find(MangledName);
844 if (DDI != DeferredDecls.end()) {
845 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit
846 // list, and remove it from DeferredDecls (since we don't need it anymore).
847 DeferredDeclsToEmit.push_back(DDI->second);
848 DeferredDecls.erase(DDI);
849 } else if (const FunctionDecl *FD = cast_or_null<FunctionDecl>(D.getDecl())) {
850 // If this the first reference to a C++ inline function in a class, queue up
851 // the deferred function body for emission. These are not seen as
852 // top-level declarations.
853 if (FD->isThisDeclarationADefinition() && MayDeferGeneration(FD))
854 DeferredDeclsToEmit.push_back(D);
855 // A called constructor which has no definition or declaration need be
857 else if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(FD)) {
858 if (CD->isImplicit()) {
859 assert(CD->isUsed() && "Sema doesn't consider constructor as used.");
860 DeferredDeclsToEmit.push_back(D);
862 } else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(FD)) {
863 if (DD->isImplicit()) {
864 assert(DD->isUsed() && "Sema doesn't consider destructor as used.");
865 DeferredDeclsToEmit.push_back(D);
867 } else if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
868 if (MD->isCopyAssignment() && MD->isImplicit()) {
869 assert(MD->isUsed() && "Sema doesn't consider CopyAssignment as used.");
870 DeferredDeclsToEmit.push_back(D);
875 // Make sure the result is of the requested type.
876 if (!IsIncompleteFunction) {
877 assert(F->getType()->getElementType() == Ty);
881 const llvm::Type *PTy = llvm::PointerType::getUnqual(Ty);
882 return llvm::ConstantExpr::getBitCast(F, PTy);
885 /// GetAddrOfFunction - Return the address of the given function. If Ty is
886 /// non-null, then this function will use the specified type if it has to
887 /// create it (this occurs when we see a definition of the function).
888 llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD,
889 const llvm::Type *Ty) {
890 // If there was no specific requested type, just convert it now.
892 Ty = getTypes().ConvertType(cast<ValueDecl>(GD.getDecl())->getType());
894 llvm::StringRef MangledName = getMangledName(GD);
895 return GetOrCreateLLVMFunction(MangledName, Ty, GD);
898 /// CreateRuntimeFunction - Create a new runtime function with the specified
901 CodeGenModule::CreateRuntimeFunction(const llvm::FunctionType *FTy,
902 llvm::StringRef Name) {
903 return GetOrCreateLLVMFunction(Name, FTy, GlobalDecl());
906 static bool DeclIsConstantGlobal(ASTContext &Context, const VarDecl *D) {
907 if (!D->getType().isConstant(Context) && !D->getType()->isReferenceType())
909 if (Context.getLangOptions().CPlusPlus &&
910 Context.getBaseElementType(D->getType())->getAs<RecordType>()) {
911 // FIXME: We should do something fancier here!
917 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module,
918 /// create and return an llvm GlobalVariable with the specified type. If there
919 /// is something in the module with the specified name, return it potentially
920 /// bitcasted to the right type.
922 /// If D is non-null, it specifies a decl that correspond to this. This is used
923 /// to set the attributes on the global when it is first created.
925 CodeGenModule::GetOrCreateLLVMGlobal(llvm::StringRef MangledName,
926 const llvm::PointerType *Ty,
928 // Lookup the entry, lazily creating it if necessary.
929 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
931 if (WeakRefReferences.count(Entry)) {
932 if (D && !D->hasAttr<WeakAttr>())
933 Entry->setLinkage(llvm::Function::ExternalLinkage);
935 WeakRefReferences.erase(Entry);
938 if (Entry->getType() == Ty)
941 // Make sure the result is of the correct type.
942 return llvm::ConstantExpr::getBitCast(Entry, Ty);
945 // This is the first use or definition of a mangled name. If there is a
946 // deferred decl with this name, remember that we need to emit it at the end
948 llvm::StringMap<GlobalDecl>::iterator DDI = DeferredDecls.find(MangledName);
949 if (DDI != DeferredDecls.end()) {
950 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit
951 // list, and remove it from DeferredDecls (since we don't need it anymore).
952 DeferredDeclsToEmit.push_back(DDI->second);
953 DeferredDecls.erase(DDI);
956 llvm::GlobalVariable *GV =
957 new llvm::GlobalVariable(getModule(), Ty->getElementType(), false,
958 llvm::GlobalValue::ExternalLinkage,
960 false, Ty->getAddressSpace());
962 // Handle things which are present even on external declarations.
964 // FIXME: This code is overly simple and should be merged with other global
966 GV->setConstant(DeclIsConstantGlobal(Context, D));
968 // FIXME: Merge with other attribute handling code.
969 if (D->getStorageClass() == SC_PrivateExtern)
970 GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
972 if (D->hasAttr<WeakAttr>() ||
973 D->hasAttr<WeakImportAttr>())
974 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage);
976 GV->setThreadLocal(D->isThreadSpecified());
983 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the
984 /// given global variable. If Ty is non-null and if the global doesn't exist,
985 /// then it will be greated with the specified type instead of whatever the
986 /// normal requested type would be.
987 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D,
988 const llvm::Type *Ty) {
989 assert(D->hasGlobalStorage() && "Not a global variable");
990 QualType ASTTy = D->getType();
992 Ty = getTypes().ConvertTypeForMem(ASTTy);
994 const llvm::PointerType *PTy =
995 llvm::PointerType::get(Ty, ASTTy.getAddressSpace());
997 llvm::StringRef MangledName = getMangledName(D);
998 return GetOrCreateLLVMGlobal(MangledName, PTy, D);
1001 /// CreateRuntimeVariable - Create a new runtime global variable with the
1002 /// specified type and name.
1004 CodeGenModule::CreateRuntimeVariable(const llvm::Type *Ty,
1005 llvm::StringRef Name) {
1006 return GetOrCreateLLVMGlobal(Name, llvm::PointerType::getUnqual(Ty), 0);
1009 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) {
1010 assert(!D->getInit() && "Cannot emit definite definitions here!");
1012 if (MayDeferGeneration(D)) {
1013 // If we have not seen a reference to this variable yet, place it
1014 // into the deferred declarations table to be emitted if needed
1016 llvm::StringRef MangledName = getMangledName(D);
1017 if (!GetGlobalValue(MangledName)) {
1018 DeferredDecls[MangledName] = D;
1023 // The tentative definition is the only definition.
1024 EmitGlobalVarDefinition(D);
1027 void CodeGenModule::EmitVTable(CXXRecordDecl *Class, bool DefinitionRequired) {
1028 if (DefinitionRequired)
1029 getVTables().GenerateClassData(getVTableLinkage(Class), Class);
1032 llvm::GlobalVariable::LinkageTypes
1033 CodeGenModule::getVTableLinkage(const CXXRecordDecl *RD) {
1034 if (RD->isInAnonymousNamespace() || !RD->hasLinkage())
1035 return llvm::GlobalVariable::InternalLinkage;
1037 if (const CXXMethodDecl *KeyFunction
1038 = RD->getASTContext().getKeyFunction(RD)) {
1039 // If this class has a key function, use that to determine the linkage of
1041 const FunctionDecl *Def = 0;
1042 if (KeyFunction->hasBody(Def))
1043 KeyFunction = cast<CXXMethodDecl>(Def);
1045 switch (KeyFunction->getTemplateSpecializationKind()) {
1046 case TSK_Undeclared:
1047 case TSK_ExplicitSpecialization:
1048 if (KeyFunction->isInlined())
1049 return llvm::GlobalVariable::WeakODRLinkage;
1051 return llvm::GlobalVariable::ExternalLinkage;
1053 case TSK_ImplicitInstantiation:
1054 case TSK_ExplicitInstantiationDefinition:
1055 return llvm::GlobalVariable::WeakODRLinkage;
1057 case TSK_ExplicitInstantiationDeclaration:
1058 // FIXME: Use available_externally linkage. However, this currently
1059 // breaks LLVM's build due to undefined symbols.
1060 // return llvm::GlobalVariable::AvailableExternallyLinkage;
1061 return llvm::GlobalVariable::WeakODRLinkage;
1065 switch (RD->getTemplateSpecializationKind()) {
1066 case TSK_Undeclared:
1067 case TSK_ExplicitSpecialization:
1068 case TSK_ImplicitInstantiation:
1069 case TSK_ExplicitInstantiationDefinition:
1070 return llvm::GlobalVariable::WeakODRLinkage;
1072 case TSK_ExplicitInstantiationDeclaration:
1073 // FIXME: Use available_externally linkage. However, this currently
1074 // breaks LLVM's build due to undefined symbols.
1075 // return llvm::GlobalVariable::AvailableExternallyLinkage;
1076 return llvm::GlobalVariable::WeakODRLinkage;
1079 // Silence GCC warning.
1080 return llvm::GlobalVariable::WeakODRLinkage;
1083 CharUnits CodeGenModule::GetTargetTypeStoreSize(const llvm::Type *Ty) const {
1084 return CharUnits::fromQuantity(
1085 TheTargetData.getTypeStoreSizeInBits(Ty) / Context.getCharWidth());
1088 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
1089 llvm::Constant *Init = 0;
1090 QualType ASTTy = D->getType();
1091 bool NonConstInit = false;
1093 const Expr *InitExpr = D->getAnyInitializer();
1096 // This is a tentative definition; tentative definitions are
1097 // implicitly initialized with { 0 }.
1099 // Note that tentative definitions are only emitted at the end of
1100 // a translation unit, so they should never have incomplete
1101 // type. In addition, EmitTentativeDefinition makes sure that we
1102 // never attempt to emit a tentative definition if a real one
1103 // exists. A use may still exists, however, so we still may need
1105 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type");
1106 Init = EmitNullConstant(D->getType());
1108 Init = EmitConstantExpr(InitExpr, D->getType());
1110 QualType T = InitExpr->getType();
1111 if (D->getType()->isReferenceType())
1114 if (getLangOptions().CPlusPlus) {
1115 EmitCXXGlobalVarDeclInitFunc(D);
1116 Init = EmitNullConstant(T);
1117 NonConstInit = true;
1119 ErrorUnsupported(D, "static initializer");
1120 Init = llvm::UndefValue::get(getTypes().ConvertType(T));
1123 // We don't need an initializer, so remove the entry for the delayed
1124 // initializer position (just in case this entry was delayed).
1125 if (getLangOptions().CPlusPlus)
1126 DelayedCXXInitPosition.erase(D);
1130 const llvm::Type* InitType = Init->getType();
1131 llvm::Constant *Entry = GetAddrOfGlobalVar(D, InitType);
1133 // Strip off a bitcast if we got one back.
1134 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) {
1135 assert(CE->getOpcode() == llvm::Instruction::BitCast ||
1136 // all zero index gep.
1137 CE->getOpcode() == llvm::Instruction::GetElementPtr);
1138 Entry = CE->getOperand(0);
1141 // Entry is now either a Function or GlobalVariable.
1142 llvm::GlobalVariable *GV = dyn_cast<llvm::GlobalVariable>(Entry);
1144 // We have a definition after a declaration with the wrong type.
1145 // We must make a new GlobalVariable* and update everything that used OldGV
1146 // (a declaration or tentative definition) with the new GlobalVariable*
1147 // (which will be a definition).
1149 // This happens if there is a prototype for a global (e.g.
1150 // "extern int x[];") and then a definition of a different type (e.g.
1151 // "int x[10];"). This also happens when an initializer has a different type
1152 // from the type of the global (this happens with unions).
1154 GV->getType()->getElementType() != InitType ||
1155 GV->getType()->getAddressSpace() != ASTTy.getAddressSpace()) {
1157 // Move the old entry aside so that we'll create a new one.
1158 Entry->setName(llvm::StringRef());
1160 // Make a new global with the correct type, this is now guaranteed to work.
1161 GV = cast<llvm::GlobalVariable>(GetAddrOfGlobalVar(D, InitType));
1163 // Replace all uses of the old global with the new global
1164 llvm::Constant *NewPtrForOldDecl =
1165 llvm::ConstantExpr::getBitCast(GV, Entry->getType());
1166 Entry->replaceAllUsesWith(NewPtrForOldDecl);
1168 // Erase the old global, since it is no longer used.
1169 cast<llvm::GlobalValue>(Entry)->eraseFromParent();
1172 if (const AnnotateAttr *AA = D->getAttr<AnnotateAttr>()) {
1173 SourceManager &SM = Context.getSourceManager();
1174 AddAnnotation(EmitAnnotateAttr(GV, AA,
1175 SM.getInstantiationLineNumber(D->getLocation())));
1178 GV->setInitializer(Init);
1180 // If it is safe to mark the global 'constant', do so now.
1181 GV->setConstant(false);
1182 if (!NonConstInit && DeclIsConstantGlobal(Context, D))
1183 GV->setConstant(true);
1185 GV->setAlignment(getContext().getDeclAlign(D).getQuantity());
1187 // Set the llvm linkage type as appropriate.
1188 GVALinkage Linkage = getContext().GetGVALinkageForVariable(D);
1189 if (Linkage == GVA_Internal)
1190 GV->setLinkage(llvm::Function::InternalLinkage);
1191 else if (D->hasAttr<DLLImportAttr>())
1192 GV->setLinkage(llvm::Function::DLLImportLinkage);
1193 else if (D->hasAttr<DLLExportAttr>())
1194 GV->setLinkage(llvm::Function::DLLExportLinkage);
1195 else if (D->hasAttr<WeakAttr>()) {
1196 if (GV->isConstant())
1197 GV->setLinkage(llvm::GlobalVariable::WeakODRLinkage);
1199 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage);
1200 } else if (Linkage == GVA_TemplateInstantiation ||
1201 Linkage == GVA_ExplicitTemplateInstantiation)
1202 // FIXME: It seems like we can provide more specific linkage here
1203 // (LinkOnceODR, WeakODR).
1204 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage);
1205 else if (!getLangOptions().CPlusPlus && !CodeGenOpts.NoCommon &&
1206 !D->hasExternalStorage() && !D->getInit() &&
1207 !D->getAttr<SectionAttr>() && !D->isThreadSpecified()) {
1208 // Thread local vars aren't considered common linkage.
1209 GV->setLinkage(llvm::GlobalVariable::CommonLinkage);
1210 // common vars aren't constant even if declared const.
1211 GV->setConstant(false);
1213 GV->setLinkage(llvm::GlobalVariable::ExternalLinkage);
1215 SetCommonAttributes(D, GV);
1217 // Emit global variable debug information.
1218 if (CGDebugInfo *DI = getDebugInfo()) {
1219 DI->setLocation(D->getLocation());
1220 DI->EmitGlobalVariable(GV, D);
1224 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we
1225 /// implement a function with no prototype, e.g. "int foo() {}". If there are
1226 /// existing call uses of the old function in the module, this adjusts them to
1227 /// call the new function directly.
1229 /// This is not just a cleanup: the always_inline pass requires direct calls to
1230 /// functions to be able to inline them. If there is a bitcast in the way, it
1231 /// won't inline them. Instcombine normally deletes these calls, but it isn't
1233 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old,
1234 llvm::Function *NewFn) {
1235 // If we're redefining a global as a function, don't transform it.
1236 llvm::Function *OldFn = dyn_cast<llvm::Function>(Old);
1237 if (OldFn == 0) return;
1239 const llvm::Type *NewRetTy = NewFn->getReturnType();
1240 llvm::SmallVector<llvm::Value*, 4> ArgList;
1242 for (llvm::Value::use_iterator UI = OldFn->use_begin(), E = OldFn->use_end();
1244 // TODO: Do invokes ever occur in C code? If so, we should handle them too.
1245 llvm::Value::use_iterator I = UI++; // Increment before the CI is erased.
1246 llvm::CallInst *CI = dyn_cast<llvm::CallInst>(*I);
1247 if (!CI) continue; // FIXME: when we allow Invoke, just do CallSite CS(*I)
1248 llvm::CallSite CS(CI);
1249 if (!CI || !CS.isCallee(I)) continue;
1251 // If the return types don't match exactly, and if the call isn't dead, then
1252 // we can't transform this call.
1253 if (CI->getType() != NewRetTy && !CI->use_empty())
1256 // If the function was passed too few arguments, don't transform. If extra
1257 // arguments were passed, we silently drop them. If any of the types
1258 // mismatch, we don't transform.
1260 bool DontTransform = false;
1261 for (llvm::Function::arg_iterator AI = NewFn->arg_begin(),
1262 E = NewFn->arg_end(); AI != E; ++AI, ++ArgNo) {
1263 if (CS.arg_size() == ArgNo ||
1264 CS.getArgument(ArgNo)->getType() != AI->getType()) {
1265 DontTransform = true;
1272 // Okay, we can transform this. Create the new call instruction and copy
1273 // over the required information.
1274 ArgList.append(CS.arg_begin(), CS.arg_begin() + ArgNo);
1275 llvm::CallInst *NewCall = llvm::CallInst::Create(NewFn, ArgList.begin(),
1276 ArgList.end(), "", CI);
1278 if (!NewCall->getType()->isVoidTy())
1279 NewCall->takeName(CI);
1280 NewCall->setAttributes(CI->getAttributes());
1281 NewCall->setCallingConv(CI->getCallingConv());
1283 // Finally, remove the old call, replacing any uses with the new one.
1284 if (!CI->use_empty())
1285 CI->replaceAllUsesWith(NewCall);
1287 // Copy debug location attached to CI.
1288 if (!CI->getDebugLoc().isUnknown())
1289 NewCall->setDebugLoc(CI->getDebugLoc());
1290 CI->eraseFromParent();
1295 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD) {
1296 const FunctionDecl *D = cast<FunctionDecl>(GD.getDecl());
1297 const llvm::FunctionType *Ty = getTypes().GetFunctionType(GD);
1298 getCXXABI().getMangleContext().mangleInitDiscriminator();
1299 // Get or create the prototype for the function.
1300 llvm::Constant *Entry = GetAddrOfFunction(GD, Ty);
1302 // Strip off a bitcast if we got one back.
1303 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) {
1304 assert(CE->getOpcode() == llvm::Instruction::BitCast);
1305 Entry = CE->getOperand(0);
1309 if (cast<llvm::GlobalValue>(Entry)->getType()->getElementType() != Ty) {
1310 llvm::GlobalValue *OldFn = cast<llvm::GlobalValue>(Entry);
1312 // If the types mismatch then we have to rewrite the definition.
1313 assert(OldFn->isDeclaration() &&
1314 "Shouldn't replace non-declaration");
1316 // F is the Function* for the one with the wrong type, we must make a new
1317 // Function* and update everything that used F (a declaration) with the new
1318 // Function* (which will be a definition).
1320 // This happens if there is a prototype for a function
1321 // (e.g. "int f()") and then a definition of a different type
1322 // (e.g. "int f(int x)"). Move the old function aside so that it
1323 // doesn't interfere with GetAddrOfFunction.
1324 OldFn->setName(llvm::StringRef());
1325 llvm::Function *NewFn = cast<llvm::Function>(GetAddrOfFunction(GD, Ty));
1327 // If this is an implementation of a function without a prototype, try to
1328 // replace any existing uses of the function (which may be calls) with uses
1329 // of the new function
1330 if (D->getType()->isFunctionNoProtoType()) {
1331 ReplaceUsesOfNonProtoTypeWithRealFunction(OldFn, NewFn);
1332 OldFn->removeDeadConstantUsers();
1335 // Replace uses of F with the Function we will endow with a body.
1336 if (!Entry->use_empty()) {
1337 llvm::Constant *NewPtrForOldDecl =
1338 llvm::ConstantExpr::getBitCast(NewFn, Entry->getType());
1339 Entry->replaceAllUsesWith(NewPtrForOldDecl);
1342 // Ok, delete the old function now, which is dead.
1343 OldFn->eraseFromParent();
1348 llvm::Function *Fn = cast<llvm::Function>(Entry);
1349 setFunctionLinkage(D, Fn);
1351 CodeGenFunction(*this).GenerateCode(D, Fn);
1353 SetFunctionDefinitionAttributes(D, Fn);
1354 SetLLVMFunctionAttributesForDefinition(D, Fn);
1356 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>())
1357 AddGlobalCtor(Fn, CA->getPriority());
1358 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>())
1359 AddGlobalDtor(Fn, DA->getPriority());
1362 void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) {
1363 const ValueDecl *D = cast<ValueDecl>(GD.getDecl());
1364 const AliasAttr *AA = D->getAttr<AliasAttr>();
1365 assert(AA && "Not an alias?");
1367 llvm::StringRef MangledName = getMangledName(GD);
1369 // If there is a definition in the module, then it wins over the alias.
1370 // This is dubious, but allow it to be safe. Just ignore the alias.
1371 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
1372 if (Entry && !Entry->isDeclaration())
1375 const llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType());
1377 // Create a reference to the named value. This ensures that it is emitted
1378 // if a deferred decl.
1379 llvm::Constant *Aliasee;
1380 if (isa<llvm::FunctionType>(DeclTy))
1381 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GlobalDecl());
1383 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(),
1384 llvm::PointerType::getUnqual(DeclTy), 0);
1386 // Create the new alias itself, but don't set a name yet.
1387 llvm::GlobalValue *GA =
1388 new llvm::GlobalAlias(Aliasee->getType(),
1389 llvm::Function::ExternalLinkage,
1390 "", Aliasee, &getModule());
1393 assert(Entry->isDeclaration());
1395 // If there is a declaration in the module, then we had an extern followed
1396 // by the alias, as in:
1397 // extern int test6();
1399 // int test6() __attribute__((alias("test7")));
1401 // Remove it and replace uses of it with the alias.
1402 GA->takeName(Entry);
1404 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA,
1406 Entry->eraseFromParent();
1408 GA->setName(MangledName);
1411 // Set attributes which are particular to an alias; this is a
1412 // specialization of the attributes which may be set on a global
1413 // variable/function.
1414 if (D->hasAttr<DLLExportAttr>()) {
1415 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
1416 // The dllexport attribute is ignored for undefined symbols.
1418 GA->setLinkage(llvm::Function::DLLExportLinkage);
1420 GA->setLinkage(llvm::Function::DLLExportLinkage);
1422 } else if (D->hasAttr<WeakAttr>() ||
1423 D->hasAttr<WeakRefAttr>() ||
1424 D->hasAttr<WeakImportAttr>()) {
1425 GA->setLinkage(llvm::Function::WeakAnyLinkage);
1428 SetCommonAttributes(D, GA);
1431 /// getBuiltinLibFunction - Given a builtin id for a function like
1432 /// "__builtin_fabsf", return a Function* for "fabsf".
1433 llvm::Value *CodeGenModule::getBuiltinLibFunction(const FunctionDecl *FD,
1434 unsigned BuiltinID) {
1435 assert((Context.BuiltinInfo.isLibFunction(BuiltinID) ||
1436 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) &&
1439 // Get the name, skip over the __builtin_ prefix (if necessary).
1440 const char *Name = Context.BuiltinInfo.GetName(BuiltinID);
1441 if (Context.BuiltinInfo.isLibFunction(BuiltinID))
1444 const llvm::FunctionType *Ty =
1445 cast<llvm::FunctionType>(getTypes().ConvertType(FD->getType()));
1447 return GetOrCreateLLVMFunction(Name, Ty, GlobalDecl(FD));
1450 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID,const llvm::Type **Tys,
1452 return llvm::Intrinsic::getDeclaration(&getModule(),
1453 (llvm::Intrinsic::ID)IID, Tys, NumTys);
1457 llvm::Function *CodeGenModule::getMemCpyFn(const llvm::Type *DestType,
1458 const llvm::Type *SrcType,
1459 const llvm::Type *SizeType) {
1460 const llvm::Type *ArgTypes[3] = {DestType, SrcType, SizeType };
1461 return getIntrinsic(llvm::Intrinsic::memcpy, ArgTypes, 3);
1464 llvm::Function *CodeGenModule::getMemMoveFn(const llvm::Type *DestType,
1465 const llvm::Type *SrcType,
1466 const llvm::Type *SizeType) {
1467 const llvm::Type *ArgTypes[3] = {DestType, SrcType, SizeType };
1468 return getIntrinsic(llvm::Intrinsic::memmove, ArgTypes, 3);
1471 llvm::Function *CodeGenModule::getMemSetFn(const llvm::Type *DestType,
1472 const llvm::Type *SizeType) {
1473 const llvm::Type *ArgTypes[2] = { DestType, SizeType };
1474 return getIntrinsic(llvm::Intrinsic::memset, ArgTypes, 2);
1477 static llvm::StringMapEntry<llvm::Constant*> &
1478 GetConstantCFStringEntry(llvm::StringMap<llvm::Constant*> &Map,
1479 const StringLiteral *Literal,
1482 unsigned &StringLength) {
1483 llvm::StringRef String = Literal->getString();
1484 unsigned NumBytes = String.size();
1486 // Check for simple case.
1487 if (!Literal->containsNonAsciiOrNull()) {
1488 StringLength = NumBytes;
1489 return Map.GetOrCreateValue(String);
1492 // Otherwise, convert the UTF8 literals into a byte string.
1493 llvm::SmallVector<UTF16, 128> ToBuf(NumBytes);
1494 const UTF8 *FromPtr = (UTF8 *)String.data();
1495 UTF16 *ToPtr = &ToBuf[0];
1497 ConversionResult Result = ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes,
1498 &ToPtr, ToPtr + NumBytes,
1501 // Check for conversion failure.
1502 if (Result != conversionOK) {
1503 // FIXME: Have Sema::CheckObjCString() validate the UTF-8 string and remove
1504 // this duplicate code.
1505 assert(Result == sourceIllegal && "UTF-8 to UTF-16 conversion failed");
1506 StringLength = NumBytes;
1507 return Map.GetOrCreateValue(String);
1510 // ConvertUTF8toUTF16 returns the length in ToPtr.
1511 StringLength = ToPtr - &ToBuf[0];
1513 // Render the UTF-16 string into a byte array and convert to the target byte
1516 // FIXME: This isn't something we should need to do here.
1517 llvm::SmallString<128> AsBytes;
1518 AsBytes.reserve(StringLength * 2);
1519 for (unsigned i = 0; i != StringLength; ++i) {
1520 unsigned short Val = ToBuf[i];
1522 AsBytes.push_back(Val & 0xFF);
1523 AsBytes.push_back(Val >> 8);
1525 AsBytes.push_back(Val >> 8);
1526 AsBytes.push_back(Val & 0xFF);
1529 // Append one extra null character, the second is automatically added by our
1531 AsBytes.push_back(0);
1534 return Map.GetOrCreateValue(llvm::StringRef(AsBytes.data(), AsBytes.size()));
1538 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) {
1539 unsigned StringLength = 0;
1540 bool isUTF16 = false;
1541 llvm::StringMapEntry<llvm::Constant*> &Entry =
1542 GetConstantCFStringEntry(CFConstantStringMap, Literal,
1543 getTargetData().isLittleEndian(),
1544 isUTF16, StringLength);
1546 if (llvm::Constant *C = Entry.getValue())
1549 llvm::Constant *Zero =
1550 llvm::Constant::getNullValue(llvm::Type::getInt32Ty(VMContext));
1551 llvm::Constant *Zeros[] = { Zero, Zero };
1553 // If we don't already have it, get __CFConstantStringClassReference.
1554 if (!CFConstantStringClassRef) {
1555 const llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy);
1556 Ty = llvm::ArrayType::get(Ty, 0);
1557 llvm::Constant *GV = CreateRuntimeVariable(Ty,
1558 "__CFConstantStringClassReference");
1559 // Decay array -> ptr
1560 CFConstantStringClassRef =
1561 llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2);
1564 QualType CFTy = getContext().getCFConstantStringType();
1566 const llvm::StructType *STy =
1567 cast<llvm::StructType>(getTypes().ConvertType(CFTy));
1569 std::vector<llvm::Constant*> Fields(4);
1572 Fields[0] = CFConstantStringClassRef;
1575 const llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy);
1576 Fields[1] = isUTF16 ? llvm::ConstantInt::get(Ty, 0x07d0) :
1577 llvm::ConstantInt::get(Ty, 0x07C8);
1580 llvm::Constant *C = llvm::ConstantArray::get(VMContext, Entry.getKey().str());
1582 llvm::GlobalValue::LinkageTypes Linkage;
1585 // FIXME: why do utf strings get "_" labels instead of "L" labels?
1586 Linkage = llvm::GlobalValue::InternalLinkage;
1587 // Note: -fwritable-strings doesn't make unicode CFStrings writable, but
1588 // does make plain ascii ones writable.
1591 Linkage = llvm::GlobalValue::PrivateLinkage;
1592 isConstant = !Features.WritableStrings;
1595 llvm::GlobalVariable *GV =
1596 new llvm::GlobalVariable(getModule(), C->getType(), isConstant, Linkage, C,
1599 CharUnits Align = getContext().getTypeAlignInChars(getContext().ShortTy);
1600 GV->setAlignment(Align.getQuantity());
1602 Fields[2] = llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2);
1605 Ty = getTypes().ConvertType(getContext().LongTy);
1606 Fields[3] = llvm::ConstantInt::get(Ty, StringLength);
1609 C = llvm::ConstantStruct::get(STy, Fields);
1610 GV = new llvm::GlobalVariable(getModule(), C->getType(), true,
1611 llvm::GlobalVariable::PrivateLinkage, C,
1612 "_unnamed_cfstring_");
1613 if (const char *Sect = getContext().Target.getCFStringSection())
1614 GV->setSection(Sect);
1621 CodeGenModule::GetAddrOfConstantNSString(const StringLiteral *Literal) {
1622 unsigned StringLength = 0;
1623 bool isUTF16 = false;
1624 llvm::StringMapEntry<llvm::Constant*> &Entry =
1625 GetConstantCFStringEntry(CFConstantStringMap, Literal,
1626 getTargetData().isLittleEndian(),
1627 isUTF16, StringLength);
1629 if (llvm::Constant *C = Entry.getValue())
1632 llvm::Constant *Zero =
1633 llvm::Constant::getNullValue(llvm::Type::getInt32Ty(VMContext));
1634 llvm::Constant *Zeros[] = { Zero, Zero };
1636 // If we don't already have it, get _NSConstantStringClassReference.
1637 if (!NSConstantStringClassRef) {
1638 const llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy);
1639 Ty = llvm::ArrayType::get(Ty, 0);
1640 llvm::Constant *GV = CreateRuntimeVariable(Ty,
1641 Features.ObjCNonFragileABI ?
1642 "OBJC_CLASS_$_NSConstantString" :
1643 "_NSConstantStringClassReference");
1644 // Decay array -> ptr
1645 NSConstantStringClassRef =
1646 llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2);
1649 QualType NSTy = getContext().getNSConstantStringType();
1651 const llvm::StructType *STy =
1652 cast<llvm::StructType>(getTypes().ConvertType(NSTy));
1654 std::vector<llvm::Constant*> Fields(3);
1657 Fields[0] = NSConstantStringClassRef;
1660 llvm::Constant *C = llvm::ConstantArray::get(VMContext, Entry.getKey().str());
1662 llvm::GlobalValue::LinkageTypes Linkage;
1665 // FIXME: why do utf strings get "_" labels instead of "L" labels?
1666 Linkage = llvm::GlobalValue::InternalLinkage;
1667 // Note: -fwritable-strings doesn't make unicode NSStrings writable, but
1668 // does make plain ascii ones writable.
1671 Linkage = llvm::GlobalValue::PrivateLinkage;
1672 isConstant = !Features.WritableStrings;
1675 llvm::GlobalVariable *GV =
1676 new llvm::GlobalVariable(getModule(), C->getType(), isConstant, Linkage, C,
1679 CharUnits Align = getContext().getTypeAlignInChars(getContext().ShortTy);
1680 GV->setAlignment(Align.getQuantity());
1682 Fields[1] = llvm::ConstantExpr::getGetElementPtr(GV, Zeros, 2);
1685 const llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy);
1686 Fields[2] = llvm::ConstantInt::get(Ty, StringLength);
1689 C = llvm::ConstantStruct::get(STy, Fields);
1690 GV = new llvm::GlobalVariable(getModule(), C->getType(), true,
1691 llvm::GlobalVariable::PrivateLinkage, C,
1692 "_unnamed_nsstring_");
1693 // FIXME. Fix section.
1694 if (const char *Sect =
1695 Features.ObjCNonFragileABI
1696 ? getContext().Target.getNSStringNonFragileABISection()
1697 : getContext().Target.getNSStringSection())
1698 GV->setSection(Sect);
1704 /// GetStringForStringLiteral - Return the appropriate bytes for a
1705 /// string literal, properly padded to match the literal type.
1706 std::string CodeGenModule::GetStringForStringLiteral(const StringLiteral *E) {
1707 const ConstantArrayType *CAT =
1708 getContext().getAsConstantArrayType(E->getType());
1709 assert(CAT && "String isn't pointer or array!");
1711 // Resize the string to the right size.
1712 uint64_t RealLen = CAT->getSize().getZExtValue();
1715 RealLen *= getContext().Target.getWCharWidth()/8;
1717 std::string Str = E->getString().str();
1718 Str.resize(RealLen, '\0');
1723 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a
1724 /// constant array for the given string literal.
1726 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S) {
1727 // FIXME: This can be more efficient.
1728 // FIXME: We shouldn't need to bitcast the constant in the wide string case.
1729 llvm::Constant *C = GetAddrOfConstantString(GetStringForStringLiteral(S));
1731 llvm::Type *DestTy =
1732 llvm::PointerType::getUnqual(getTypes().ConvertType(S->getType()));
1733 C = llvm::ConstantExpr::getBitCast(C, DestTy);
1738 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant
1739 /// array for the given ObjCEncodeExpr node.
1741 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) {
1743 getContext().getObjCEncodingForType(E->getEncodedType(), Str);
1745 return GetAddrOfConstantCString(Str);
1749 /// GenerateWritableString -- Creates storage for a string literal.
1750 static llvm::Constant *GenerateStringLiteral(const std::string &str,
1753 const char *GlobalName) {
1754 // Create Constant for this string literal. Don't add a '\0'.
1756 llvm::ConstantArray::get(CGM.getLLVMContext(), str, false);
1758 // Create a global variable for this string
1759 return new llvm::GlobalVariable(CGM.getModule(), C->getType(), constant,
1760 llvm::GlobalValue::PrivateLinkage,
1764 /// GetAddrOfConstantString - Returns a pointer to a character array
1765 /// containing the literal. This contents are exactly that of the
1766 /// given string, i.e. it will not be null terminated automatically;
1767 /// see GetAddrOfConstantCString. Note that whether the result is
1768 /// actually a pointer to an LLVM constant depends on
1769 /// Feature.WriteableStrings.
1771 /// The result has pointer to array type.
1772 llvm::Constant *CodeGenModule::GetAddrOfConstantString(const std::string &str,
1773 const char *GlobalName) {
1774 bool IsConstant = !Features.WritableStrings;
1776 // Get the default prefix if a name wasn't specified.
1778 GlobalName = ".str";
1780 // Don't share any string literals if strings aren't constant.
1782 return GenerateStringLiteral(str, false, *this, GlobalName);
1784 llvm::StringMapEntry<llvm::Constant *> &Entry =
1785 ConstantStringMap.GetOrCreateValue(&str[0], &str[str.length()]);
1787 if (Entry.getValue())
1788 return Entry.getValue();
1790 // Create a global variable for this.
1791 llvm::Constant *C = GenerateStringLiteral(str, true, *this, GlobalName);
1796 /// GetAddrOfConstantCString - Returns a pointer to a character
1797 /// array containing the literal and a terminating '\-'
1798 /// character. The result has pointer to array type.
1799 llvm::Constant *CodeGenModule::GetAddrOfConstantCString(const std::string &str,
1800 const char *GlobalName){
1801 return GetAddrOfConstantString(str + '\0', GlobalName);
1804 /// EmitObjCPropertyImplementations - Emit information for synthesized
1805 /// properties for an implementation.
1806 void CodeGenModule::EmitObjCPropertyImplementations(const
1807 ObjCImplementationDecl *D) {
1808 for (ObjCImplementationDecl::propimpl_iterator
1809 i = D->propimpl_begin(), e = D->propimpl_end(); i != e; ++i) {
1810 ObjCPropertyImplDecl *PID = *i;
1812 // Dynamic is just for type-checking.
1813 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) {
1814 ObjCPropertyDecl *PD = PID->getPropertyDecl();
1816 // Determine which methods need to be implemented, some may have
1817 // been overridden. Note that ::isSynthesized is not the method
1818 // we want, that just indicates if the decl came from a
1819 // property. What we want to know is if the method is defined in
1820 // this implementation.
1821 if (!D->getInstanceMethod(PD->getGetterName()))
1822 CodeGenFunction(*this).GenerateObjCGetter(
1823 const_cast<ObjCImplementationDecl *>(D), PID);
1824 if (!PD->isReadOnly() &&
1825 !D->getInstanceMethod(PD->getSetterName()))
1826 CodeGenFunction(*this).GenerateObjCSetter(
1827 const_cast<ObjCImplementationDecl *>(D), PID);
1832 /// EmitObjCIvarInitializations - Emit information for ivar initialization
1833 /// for an implementation.
1834 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) {
1835 if (!Features.NeXTRuntime || D->getNumIvarInitializers() == 0)
1837 DeclContext* DC = const_cast<DeclContext*>(dyn_cast<DeclContext>(D));
1838 assert(DC && "EmitObjCIvarInitializations - null DeclContext");
1839 IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct");
1840 Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
1841 ObjCMethodDecl *DTORMethod = ObjCMethodDecl::Create(getContext(),
1843 D->getLocation(), cxxSelector,
1844 getContext().VoidTy, 0,
1845 DC, true, false, true, false,
1846 ObjCMethodDecl::Required);
1847 D->addInstanceMethod(DTORMethod);
1848 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false);
1850 II = &getContext().Idents.get(".cxx_construct");
1851 cxxSelector = getContext().Selectors.getSelector(0, &II);
1852 // The constructor returns 'self'.
1853 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create(getContext(),
1855 D->getLocation(), cxxSelector,
1856 getContext().getObjCIdType(), 0,
1857 DC, true, false, true, false,
1858 ObjCMethodDecl::Required);
1859 D->addInstanceMethod(CTORMethod);
1860 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true);
1865 /// EmitNamespace - Emit all declarations in a namespace.
1866 void CodeGenModule::EmitNamespace(const NamespaceDecl *ND) {
1867 for (RecordDecl::decl_iterator I = ND->decls_begin(), E = ND->decls_end();
1869 EmitTopLevelDecl(*I);
1872 // EmitLinkageSpec - Emit all declarations in a linkage spec.
1873 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) {
1874 if (LSD->getLanguage() != LinkageSpecDecl::lang_c &&
1875 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) {
1876 ErrorUnsupported(LSD, "linkage spec");
1880 for (RecordDecl::decl_iterator I = LSD->decls_begin(), E = LSD->decls_end();
1882 EmitTopLevelDecl(*I);
1885 /// EmitTopLevelDecl - Emit code for a single top level declaration.
1886 void CodeGenModule::EmitTopLevelDecl(Decl *D) {
1887 // If an error has occurred, stop code generation, but continue
1888 // parsing and semantic analysis (to ensure all warnings and errors
1890 if (Diags.hasErrorOccurred())
1893 // Ignore dependent declarations.
1894 if (D->getDeclContext() && D->getDeclContext()->isDependentContext())
1897 switch (D->getKind()) {
1898 case Decl::CXXConversion:
1899 case Decl::CXXMethod:
1900 case Decl::Function:
1901 // Skip function templates
1902 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate())
1905 EmitGlobal(cast<FunctionDecl>(D));
1909 EmitGlobal(cast<VarDecl>(D));
1913 case Decl::Namespace:
1914 EmitNamespace(cast<NamespaceDecl>(D));
1916 // No code generation needed.
1917 case Decl::UsingShadow:
1919 case Decl::UsingDirective:
1920 case Decl::ClassTemplate:
1921 case Decl::FunctionTemplate:
1922 case Decl::NamespaceAlias:
1924 case Decl::CXXConstructor:
1925 // Skip function templates
1926 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate())
1929 EmitCXXConstructors(cast<CXXConstructorDecl>(D));
1931 case Decl::CXXDestructor:
1932 EmitCXXDestructors(cast<CXXDestructorDecl>(D));
1935 case Decl::StaticAssert:
1939 // Objective-C Decls
1941 // Forward declarations, no (immediate) code generation.
1942 case Decl::ObjCClass:
1943 case Decl::ObjCForwardProtocol:
1944 case Decl::ObjCInterface:
1947 case Decl::ObjCCategory: {
1948 ObjCCategoryDecl *CD = cast<ObjCCategoryDecl>(D);
1949 if (CD->IsClassExtension() && CD->hasSynthBitfield())
1950 Context.ResetObjCLayout(CD->getClassInterface());
1955 case Decl::ObjCProtocol:
1956 Runtime->GenerateProtocol(cast<ObjCProtocolDecl>(D));
1959 case Decl::ObjCCategoryImpl:
1960 // Categories have properties but don't support synthesize so we
1961 // can ignore them here.
1962 Runtime->GenerateCategory(cast<ObjCCategoryImplDecl>(D));
1965 case Decl::ObjCImplementation: {
1966 ObjCImplementationDecl *OMD = cast<ObjCImplementationDecl>(D);
1967 if (Features.ObjCNonFragileABI2 && OMD->hasSynthBitfield())
1968 Context.ResetObjCLayout(OMD->getClassInterface());
1969 EmitObjCPropertyImplementations(OMD);
1970 EmitObjCIvarInitializations(OMD);
1971 Runtime->GenerateClass(OMD);
1974 case Decl::ObjCMethod: {
1975 ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(D);
1976 // If this is not a prototype, emit the body.
1978 CodeGenFunction(*this).GenerateObjCMethod(OMD);
1981 case Decl::ObjCCompatibleAlias:
1982 // compatibility-alias is a directive and has no code gen.
1985 case Decl::LinkageSpec:
1986 EmitLinkageSpec(cast<LinkageSpecDecl>(D));
1989 case Decl::FileScopeAsm: {
1990 FileScopeAsmDecl *AD = cast<FileScopeAsmDecl>(D);
1991 llvm::StringRef AsmString = AD->getAsmString()->getString();
1993 const std::string &S = getModule().getModuleInlineAsm();
1995 getModule().setModuleInlineAsm(AsmString);
1997 getModule().setModuleInlineAsm(S + '\n' + AsmString.str());
2002 // Make sure we handled everything we should, every other kind is a
2003 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind
2004 // function. Need to recode Decl::Kind to do that easily.
2005 assert(isa<TypeDecl>(D) && "Unsupported decl kind");
2009 /// Turns the given pointer into a constant.
2010 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context,
2012 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr);
2013 const llvm::Type *i64 = llvm::Type::getInt64Ty(Context);
2014 return llvm::ConstantInt::get(i64, PtrInt);
2017 static void EmitGlobalDeclMetadata(CodeGenModule &CGM,
2018 llvm::NamedMDNode *&GlobalMetadata,
2020 llvm::GlobalValue *Addr) {
2021 if (!GlobalMetadata)
2023 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs");
2025 // TODO: should we report variant information for ctors/dtors?
2026 llvm::Value *Ops[] = {
2028 GetPointerConstant(CGM.getLLVMContext(), D.getDecl())
2030 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops, 2));
2033 /// Emits metadata nodes associating all the global values in the
2034 /// current module with the Decls they came from. This is useful for
2035 /// projects using IR gen as a subroutine.
2037 /// Since there's currently no way to associate an MDNode directly
2038 /// with an llvm::GlobalValue, we create a global named metadata
2039 /// with the name 'clang.global.decl.ptrs'.
2040 void CodeGenModule::EmitDeclMetadata() {
2041 llvm::NamedMDNode *GlobalMetadata = 0;
2043 // StaticLocalDeclMap
2044 for (llvm::DenseMap<GlobalDecl,llvm::StringRef>::iterator
2045 I = MangledDeclNames.begin(), E = MangledDeclNames.end();
2047 llvm::GlobalValue *Addr = getModule().getNamedValue(I->second);
2048 EmitGlobalDeclMetadata(*this, GlobalMetadata, I->first, Addr);
2052 /// Emits metadata nodes for all the local variables in the current
2054 void CodeGenFunction::EmitDeclMetadata() {
2055 if (LocalDeclMap.empty()) return;
2057 llvm::LLVMContext &Context = getLLVMContext();
2059 // Find the unique metadata ID for this name.
2060 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr");
2062 llvm::NamedMDNode *GlobalMetadata = 0;
2064 for (llvm::DenseMap<const Decl*, llvm::Value*>::iterator
2065 I = LocalDeclMap.begin(), E = LocalDeclMap.end(); I != E; ++I) {
2066 const Decl *D = I->first;
2067 llvm::Value *Addr = I->second;
2069 if (llvm::AllocaInst *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) {
2070 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D);
2071 Alloca->setMetadata(DeclPtrKind, llvm::MDNode::get(Context, &DAddr, 1));
2072 } else if (llvm::GlobalValue *GV = dyn_cast<llvm::GlobalValue>(Addr)) {
2073 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D));
2074 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV);
2079 ///@name Custom Runtime Function Interfaces
2082 // FIXME: These can be eliminated once we can have clients just get the required
2083 // AST nodes from the builtin tables.
2085 llvm::Constant *CodeGenModule::getBlockObjectDispose() {
2086 if (BlockObjectDispose)
2087 return BlockObjectDispose;
2089 // If we saw an explicit decl, use that.
2090 if (BlockObjectDisposeDecl) {
2091 return BlockObjectDispose = GetAddrOfFunction(
2092 BlockObjectDisposeDecl,
2093 getTypes().GetFunctionType(BlockObjectDisposeDecl));
2096 // Otherwise construct the function by hand.
2097 const llvm::FunctionType *FTy;
2098 std::vector<const llvm::Type*> ArgTys;
2099 const llvm::Type *ResultType = llvm::Type::getVoidTy(VMContext);
2100 ArgTys.push_back(PtrToInt8Ty);
2101 ArgTys.push_back(llvm::Type::getInt32Ty(VMContext));
2102 FTy = llvm::FunctionType::get(ResultType, ArgTys, false);
2103 return BlockObjectDispose =
2104 CreateRuntimeFunction(FTy, "_Block_object_dispose");
2107 llvm::Constant *CodeGenModule::getBlockObjectAssign() {
2108 if (BlockObjectAssign)
2109 return BlockObjectAssign;
2111 // If we saw an explicit decl, use that.
2112 if (BlockObjectAssignDecl) {
2113 return BlockObjectAssign = GetAddrOfFunction(
2114 BlockObjectAssignDecl,
2115 getTypes().GetFunctionType(BlockObjectAssignDecl));
2118 // Otherwise construct the function by hand.
2119 const llvm::FunctionType *FTy;
2120 std::vector<const llvm::Type*> ArgTys;
2121 const llvm::Type *ResultType = llvm::Type::getVoidTy(VMContext);
2122 ArgTys.push_back(PtrToInt8Ty);
2123 ArgTys.push_back(PtrToInt8Ty);
2124 ArgTys.push_back(llvm::Type::getInt32Ty(VMContext));
2125 FTy = llvm::FunctionType::get(ResultType, ArgTys, false);
2126 return BlockObjectAssign =
2127 CreateRuntimeFunction(FTy, "_Block_object_assign");
2130 llvm::Constant *CodeGenModule::getNSConcreteGlobalBlock() {
2131 if (NSConcreteGlobalBlock)
2132 return NSConcreteGlobalBlock;
2134 // If we saw an explicit decl, use that.
2135 if (NSConcreteGlobalBlockDecl) {
2136 return NSConcreteGlobalBlock = GetAddrOfGlobalVar(
2137 NSConcreteGlobalBlockDecl,
2138 getTypes().ConvertType(NSConcreteGlobalBlockDecl->getType()));
2141 // Otherwise construct the variable by hand.
2142 return NSConcreteGlobalBlock = CreateRuntimeVariable(
2143 PtrToInt8Ty, "_NSConcreteGlobalBlock");
2146 llvm::Constant *CodeGenModule::getNSConcreteStackBlock() {
2147 if (NSConcreteStackBlock)
2148 return NSConcreteStackBlock;
2150 // If we saw an explicit decl, use that.
2151 if (NSConcreteStackBlockDecl) {
2152 return NSConcreteStackBlock = GetAddrOfGlobalVar(
2153 NSConcreteStackBlockDecl,
2154 getTypes().ConvertType(NSConcreteStackBlockDecl->getType()));
2157 // Otherwise construct the variable by hand.
2158 return NSConcreteStackBlock = CreateRuntimeVariable(
2159 PtrToInt8Ty, "_NSConcreteStackBlock");