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 "CGCUDARuntime.h"
18 #include "CGDebugInfo.h"
19 #include "CGObjCRuntime.h"
20 #include "CGOpenCLRuntime.h"
21 #include "CodeGenFunction.h"
22 #include "CodeGenTBAA.h"
23 #include "TargetInfo.h"
24 #include "clang/AST/ASTContext.h"
25 #include "clang/AST/CharUnits.h"
26 #include "clang/AST/DeclCXX.h"
27 #include "clang/AST/DeclObjC.h"
28 #include "clang/AST/DeclTemplate.h"
29 #include "clang/AST/Mangle.h"
30 #include "clang/AST/RecordLayout.h"
31 #include "clang/AST/RecursiveASTVisitor.h"
32 #include "clang/Basic/Builtins.h"
33 #include "clang/Basic/CharInfo.h"
34 #include "clang/Basic/Diagnostic.h"
35 #include "clang/Basic/Module.h"
36 #include "clang/Basic/SourceManager.h"
37 #include "clang/Basic/TargetInfo.h"
38 #include "clang/Basic/Version.h"
39 #include "clang/Frontend/CodeGenOptions.h"
40 #include "clang/Sema/SemaDiagnostic.h"
41 #include "llvm/ADT/APSInt.h"
42 #include "llvm/ADT/Triple.h"
43 #include "llvm/IR/CallingConv.h"
44 #include "llvm/IR/DataLayout.h"
45 #include "llvm/IR/Intrinsics.h"
46 #include "llvm/IR/LLVMContext.h"
47 #include "llvm/IR/Module.h"
48 #include "llvm/Support/CallSite.h"
49 #include "llvm/Support/ConvertUTF.h"
50 #include "llvm/Support/ErrorHandling.h"
51 #include "llvm/Target/Mangler.h"
53 using namespace clang;
54 using namespace CodeGen;
56 static const char AnnotationSection[] = "llvm.metadata";
58 static CGCXXABI &createCXXABI(CodeGenModule &CGM) {
59 switch (CGM.getTarget().getCXXABI().getKind()) {
60 case TargetCXXABI::GenericAArch64:
61 case TargetCXXABI::GenericARM:
62 case TargetCXXABI::iOS:
63 case TargetCXXABI::GenericItanium:
64 return *CreateItaniumCXXABI(CGM);
65 case TargetCXXABI::Microsoft:
66 return *CreateMicrosoftCXXABI(CGM);
69 llvm_unreachable("invalid C++ ABI kind");
72 CodeGenModule::CodeGenModule(ASTContext &C, const CodeGenOptions &CGO,
73 llvm::Module &M, const llvm::DataLayout &TD,
74 DiagnosticsEngine &diags)
75 : Context(C), LangOpts(C.getLangOpts()), CodeGenOpts(CGO), TheModule(M),
76 Diags(diags), TheDataLayout(TD), Target(C.getTargetInfo()),
77 ABI(createCXXABI(*this)), VMContext(M.getContext()), TBAA(0),
78 TheTargetCodeGenInfo(0), Types(*this), VTables(*this), ObjCRuntime(0),
79 OpenCLRuntime(0), CUDARuntime(0), DebugInfo(0), ARCData(0),
80 NoObjCARCExceptionsMetadata(0), RRData(0), CFConstantStringClassRef(0),
81 ConstantStringClassRef(0), NSConstantStringType(0),
82 NSConcreteGlobalBlock(0), NSConcreteStackBlock(0), BlockObjectAssign(0),
83 BlockObjectDispose(0), BlockDescriptorType(0), GenericBlockLiteralType(0),
84 LifetimeStartFn(0), LifetimeEndFn(0),
86 llvm::SpecialCaseList::createOrDie(CGO.SanitizerBlacklistFile)),
87 SanOpts(SanitizerBlacklist->isIn(M) ? SanitizerOptions::Disabled
88 : LangOpts.Sanitize) {
90 // Initialize the type cache.
91 llvm::LLVMContext &LLVMContext = M.getContext();
92 VoidTy = llvm::Type::getVoidTy(LLVMContext);
93 Int8Ty = llvm::Type::getInt8Ty(LLVMContext);
94 Int16Ty = llvm::Type::getInt16Ty(LLVMContext);
95 Int32Ty = llvm::Type::getInt32Ty(LLVMContext);
96 Int64Ty = llvm::Type::getInt64Ty(LLVMContext);
97 FloatTy = llvm::Type::getFloatTy(LLVMContext);
98 DoubleTy = llvm::Type::getDoubleTy(LLVMContext);
99 PointerWidthInBits = C.getTargetInfo().getPointerWidth(0);
100 PointerAlignInBytes =
101 C.toCharUnitsFromBits(C.getTargetInfo().getPointerAlign(0)).getQuantity();
102 IntTy = llvm::IntegerType::get(LLVMContext, C.getTargetInfo().getIntWidth());
103 IntPtrTy = llvm::IntegerType::get(LLVMContext, PointerWidthInBits);
104 Int8PtrTy = Int8Ty->getPointerTo(0);
105 Int8PtrPtrTy = Int8PtrTy->getPointerTo(0);
107 RuntimeCC = getTargetCodeGenInfo().getABIInfo().getRuntimeCC();
112 createOpenCLRuntime();
116 // Enable TBAA unless it's suppressed. ThreadSanitizer needs TBAA even at O0.
117 if (SanOpts.Thread ||
118 (!CodeGenOpts.RelaxedAliasing && CodeGenOpts.OptimizationLevel > 0))
119 TBAA = new CodeGenTBAA(Context, VMContext, CodeGenOpts, getLangOpts(),
120 ABI.getMangleContext());
122 // If debug info or coverage generation is enabled, create the CGDebugInfo
124 if (CodeGenOpts.getDebugInfo() != CodeGenOptions::NoDebugInfo ||
125 CodeGenOpts.EmitGcovArcs ||
126 CodeGenOpts.EmitGcovNotes)
127 DebugInfo = new CGDebugInfo(*this);
129 Block.GlobalUniqueCount = 0;
131 if (C.getLangOpts().ObjCAutoRefCount)
132 ARCData = new ARCEntrypoints();
133 RRData = new RREntrypoints();
136 CodeGenModule::~CodeGenModule() {
138 delete OpenCLRuntime;
140 delete TheTargetCodeGenInfo;
148 void CodeGenModule::createObjCRuntime() {
149 // This is just isGNUFamily(), but we want to force implementors of
150 // new ABIs to decide how best to do this.
151 switch (LangOpts.ObjCRuntime.getKind()) {
152 case ObjCRuntime::GNUstep:
153 case ObjCRuntime::GCC:
154 case ObjCRuntime::ObjFW:
155 ObjCRuntime = CreateGNUObjCRuntime(*this);
158 case ObjCRuntime::FragileMacOSX:
159 case ObjCRuntime::MacOSX:
160 case ObjCRuntime::iOS:
161 ObjCRuntime = CreateMacObjCRuntime(*this);
164 llvm_unreachable("bad runtime kind");
167 void CodeGenModule::createOpenCLRuntime() {
168 OpenCLRuntime = new CGOpenCLRuntime(*this);
171 void CodeGenModule::createCUDARuntime() {
172 CUDARuntime = CreateNVCUDARuntime(*this);
175 void CodeGenModule::applyReplacements() {
176 for (ReplacementsTy::iterator I = Replacements.begin(),
177 E = Replacements.end();
179 StringRef MangledName = I->first();
180 llvm::Constant *Replacement = I->second;
181 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
184 llvm::Function *OldF = cast<llvm::Function>(Entry);
185 llvm::Function *NewF = dyn_cast<llvm::Function>(Replacement);
187 llvm::ConstantExpr *CE = cast<llvm::ConstantExpr>(Replacement);
188 assert(CE->getOpcode() == llvm::Instruction::BitCast ||
189 CE->getOpcode() == llvm::Instruction::GetElementPtr);
190 NewF = dyn_cast<llvm::Function>(CE->getOperand(0));
193 // Replace old with new, but keep the old order.
194 OldF->replaceAllUsesWith(Replacement);
196 NewF->removeFromParent();
197 OldF->getParent()->getFunctionList().insertAfter(OldF, NewF);
199 OldF->eraseFromParent();
203 void CodeGenModule::checkAliases() {
205 for (std::vector<GlobalDecl>::iterator I = Aliases.begin(),
206 E = Aliases.end(); I != E; ++I) {
207 const GlobalDecl &GD = *I;
208 const ValueDecl *D = cast<ValueDecl>(GD.getDecl());
209 const AliasAttr *AA = D->getAttr<AliasAttr>();
210 StringRef MangledName = getMangledName(GD);
211 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
212 llvm::GlobalAlias *Alias = cast<llvm::GlobalAlias>(Entry);
213 llvm::GlobalValue *GV = Alias->getAliasedGlobal();
214 if (GV->isDeclaration()) {
216 getDiags().Report(AA->getLocation(), diag::err_alias_to_undefined);
217 } else if (!Alias->resolveAliasedGlobal(/*stopOnWeak*/ false)) {
219 getDiags().Report(AA->getLocation(), diag::err_cyclic_alias);
225 for (std::vector<GlobalDecl>::iterator I = Aliases.begin(),
226 E = Aliases.end(); I != E; ++I) {
227 const GlobalDecl &GD = *I;
228 StringRef MangledName = getMangledName(GD);
229 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
230 llvm::GlobalAlias *Alias = cast<llvm::GlobalAlias>(Entry);
231 Alias->replaceAllUsesWith(llvm::UndefValue::get(Alias->getType()));
232 Alias->eraseFromParent();
236 void CodeGenModule::Release() {
240 EmitCXXGlobalInitFunc();
241 EmitCXXGlobalDtorFunc();
242 EmitCXXThreadLocalInitFunc();
244 if (llvm::Function *ObjCInitFunction = ObjCRuntime->ModuleInitFunction())
245 AddGlobalCtor(ObjCInitFunction);
246 EmitCtorList(GlobalCtors, "llvm.global_ctors");
247 EmitCtorList(GlobalDtors, "llvm.global_dtors");
248 EmitGlobalAnnotations();
249 EmitStaticExternCAliases();
252 if (CodeGenOpts.Autolink &&
253 (Context.getLangOpts().Modules || !LinkerOptionsMetadata.empty())) {
254 EmitModuleLinkOptions();
256 if (CodeGenOpts.DwarfVersion)
257 // We actually want the latest version when there are conflicts.
258 // We can change from Warning to Latest if such mode is supported.
259 getModule().addModuleFlag(llvm::Module::Warning, "Dwarf Version",
260 CodeGenOpts.DwarfVersion);
262 // We support a single version in the linked module: error out when
263 // modules do not have the same version. We are going to implement dropping
264 // debug info when the version number is not up-to-date. Once that is
265 // done, the bitcode linker is not going to see modules with different
267 getModule().addModuleFlag(llvm::Module::Error, "Debug Info Version",
268 llvm::DEBUG_METADATA_VERSION);
270 SimplifyPersonality();
272 if (getCodeGenOpts().EmitDeclMetadata)
275 if (getCodeGenOpts().EmitGcovArcs || getCodeGenOpts().EmitGcovNotes)
279 DebugInfo->finalize();
281 EmitVersionIdentMetadata();
284 void CodeGenModule::UpdateCompletedType(const TagDecl *TD) {
285 // Make sure that this type is translated.
286 Types.UpdateCompletedType(TD);
289 llvm::MDNode *CodeGenModule::getTBAAInfo(QualType QTy) {
292 return TBAA->getTBAAInfo(QTy);
295 llvm::MDNode *CodeGenModule::getTBAAInfoForVTablePtr() {
298 return TBAA->getTBAAInfoForVTablePtr();
301 llvm::MDNode *CodeGenModule::getTBAAStructInfo(QualType QTy) {
304 return TBAA->getTBAAStructInfo(QTy);
307 llvm::MDNode *CodeGenModule::getTBAAStructTypeInfo(QualType QTy) {
310 return TBAA->getTBAAStructTypeInfo(QTy);
313 llvm::MDNode *CodeGenModule::getTBAAStructTagInfo(QualType BaseTy,
314 llvm::MDNode *AccessN,
318 return TBAA->getTBAAStructTagInfo(BaseTy, AccessN, O);
321 /// Decorate the instruction with a TBAA tag. For both scalar TBAA
322 /// and struct-path aware TBAA, the tag has the same format:
323 /// base type, access type and offset.
324 /// When ConvertTypeToTag is true, we create a tag based on the scalar type.
325 void CodeGenModule::DecorateInstruction(llvm::Instruction *Inst,
326 llvm::MDNode *TBAAInfo,
327 bool ConvertTypeToTag) {
328 if (ConvertTypeToTag && TBAA)
329 Inst->setMetadata(llvm::LLVMContext::MD_tbaa,
330 TBAA->getTBAAScalarTagInfo(TBAAInfo));
332 Inst->setMetadata(llvm::LLVMContext::MD_tbaa, TBAAInfo);
335 void CodeGenModule::Error(SourceLocation loc, StringRef error) {
336 unsigned diagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, error);
337 getDiags().Report(Context.getFullLoc(loc), diagID);
340 /// ErrorUnsupported - Print out an error that codegen doesn't support the
341 /// specified stmt yet.
342 void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type) {
343 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error,
344 "cannot compile this %0 yet");
345 std::string Msg = Type;
346 getDiags().Report(Context.getFullLoc(S->getLocStart()), DiagID)
347 << Msg << S->getSourceRange();
350 /// ErrorUnsupported - Print out an error that codegen doesn't support the
351 /// specified decl yet.
352 void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type) {
353 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error,
354 "cannot compile this %0 yet");
355 std::string Msg = Type;
356 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg;
359 llvm::ConstantInt *CodeGenModule::getSize(CharUnits size) {
360 return llvm::ConstantInt::get(SizeTy, size.getQuantity());
363 void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV,
364 const NamedDecl *D) const {
365 // Internal definitions always have default visibility.
366 if (GV->hasLocalLinkage()) {
367 GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
371 // Set visibility for definitions.
372 LinkageInfo LV = D->getLinkageAndVisibility();
373 if (LV.isVisibilityExplicit() || !GV->hasAvailableExternallyLinkage())
374 GV->setVisibility(GetLLVMVisibility(LV.getVisibility()));
377 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(StringRef S) {
378 return llvm::StringSwitch<llvm::GlobalVariable::ThreadLocalMode>(S)
379 .Case("global-dynamic", llvm::GlobalVariable::GeneralDynamicTLSModel)
380 .Case("local-dynamic", llvm::GlobalVariable::LocalDynamicTLSModel)
381 .Case("initial-exec", llvm::GlobalVariable::InitialExecTLSModel)
382 .Case("local-exec", llvm::GlobalVariable::LocalExecTLSModel);
385 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(
386 CodeGenOptions::TLSModel M) {
388 case CodeGenOptions::GeneralDynamicTLSModel:
389 return llvm::GlobalVariable::GeneralDynamicTLSModel;
390 case CodeGenOptions::LocalDynamicTLSModel:
391 return llvm::GlobalVariable::LocalDynamicTLSModel;
392 case CodeGenOptions::InitialExecTLSModel:
393 return llvm::GlobalVariable::InitialExecTLSModel;
394 case CodeGenOptions::LocalExecTLSModel:
395 return llvm::GlobalVariable::LocalExecTLSModel;
397 llvm_unreachable("Invalid TLS model!");
400 void CodeGenModule::setTLSMode(llvm::GlobalVariable *GV,
401 const VarDecl &D) const {
402 assert(D.getTLSKind() && "setting TLS mode on non-TLS var!");
404 llvm::GlobalVariable::ThreadLocalMode TLM;
405 TLM = GetLLVMTLSModel(CodeGenOpts.getDefaultTLSModel());
407 // Override the TLS model if it is explicitly specified.
408 if (D.hasAttr<TLSModelAttr>()) {
409 const TLSModelAttr *Attr = D.getAttr<TLSModelAttr>();
410 TLM = GetLLVMTLSModel(Attr->getModel());
413 GV->setThreadLocalMode(TLM);
416 /// Set the symbol visibility of type information (vtable and RTTI)
417 /// associated with the given type.
418 void CodeGenModule::setTypeVisibility(llvm::GlobalValue *GV,
419 const CXXRecordDecl *RD,
420 TypeVisibilityKind TVK) const {
421 setGlobalVisibility(GV, RD);
423 if (!CodeGenOpts.HiddenWeakVTables)
426 // We never want to drop the visibility for RTTI names.
427 if (TVK == TVK_ForRTTIName)
430 // We want to drop the visibility to hidden for weak type symbols.
431 // This isn't possible if there might be unresolved references
432 // elsewhere that rely on this symbol being visible.
434 // This should be kept roughly in sync with setThunkVisibility
438 if (GV->getLinkage() != llvm::GlobalVariable::LinkOnceODRLinkage ||
439 GV->getVisibility() != llvm::GlobalVariable::DefaultVisibility)
442 // Don't override an explicit visibility attribute.
443 if (RD->getExplicitVisibility(NamedDecl::VisibilityForType))
446 switch (RD->getTemplateSpecializationKind()) {
447 // We have to disable the optimization if this is an EI definition
448 // because there might be EI declarations in other shared objects.
449 case TSK_ExplicitInstantiationDefinition:
450 case TSK_ExplicitInstantiationDeclaration:
453 // Every use of a non-template class's type information has to emit it.
457 // In theory, implicit instantiations can ignore the possibility of
458 // an explicit instantiation declaration because there necessarily
459 // must be an EI definition somewhere with default visibility. In
460 // practice, it's possible to have an explicit instantiation for
461 // an arbitrary template class, and linkers aren't necessarily able
462 // to deal with mixed-visibility symbols.
463 case TSK_ExplicitSpecialization:
464 case TSK_ImplicitInstantiation:
468 // If there's a key function, there may be translation units
469 // that don't have the key function's definition. But ignore
470 // this if we're emitting RTTI under -fno-rtti.
471 if (!(TVK != TVK_ForRTTI) || LangOpts.RTTI) {
472 // FIXME: what should we do if we "lose" the key function during
473 // the emission of the file?
474 if (Context.getCurrentKeyFunction(RD))
478 // Otherwise, drop the visibility to hidden.
479 GV->setVisibility(llvm::GlobalValue::HiddenVisibility);
480 GV->setUnnamedAddr(true);
483 StringRef CodeGenModule::getMangledName(GlobalDecl GD) {
484 const NamedDecl *ND = cast<NamedDecl>(GD.getDecl());
486 StringRef &Str = MangledDeclNames[GD.getCanonicalDecl()];
490 if (!getCXXABI().getMangleContext().shouldMangleDeclName(ND)) {
491 IdentifierInfo *II = ND->getIdentifier();
492 assert(II && "Attempt to mangle unnamed decl.");
498 SmallString<256> Buffer;
499 llvm::raw_svector_ostream Out(Buffer);
500 if (const CXXConstructorDecl *D = dyn_cast<CXXConstructorDecl>(ND))
501 getCXXABI().getMangleContext().mangleCXXCtor(D, GD.getCtorType(), Out);
502 else if (const CXXDestructorDecl *D = dyn_cast<CXXDestructorDecl>(ND))
503 getCXXABI().getMangleContext().mangleCXXDtor(D, GD.getDtorType(), Out);
505 getCXXABI().getMangleContext().mangleName(ND, Out);
507 // Allocate space for the mangled name.
509 size_t Length = Buffer.size();
510 char *Name = MangledNamesAllocator.Allocate<char>(Length);
511 std::copy(Buffer.begin(), Buffer.end(), Name);
513 Str = StringRef(Name, Length);
518 void CodeGenModule::getBlockMangledName(GlobalDecl GD, MangleBuffer &Buffer,
519 const BlockDecl *BD) {
520 MangleContext &MangleCtx = getCXXABI().getMangleContext();
521 const Decl *D = GD.getDecl();
522 llvm::raw_svector_ostream Out(Buffer.getBuffer());
524 MangleCtx.mangleGlobalBlock(BD,
525 dyn_cast_or_null<VarDecl>(initializedGlobalDecl.getDecl()), Out);
526 else if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(D))
527 MangleCtx.mangleCtorBlock(CD, GD.getCtorType(), BD, Out);
528 else if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(D))
529 MangleCtx.mangleDtorBlock(DD, GD.getDtorType(), BD, Out);
531 MangleCtx.mangleBlock(cast<DeclContext>(D), BD, Out);
534 llvm::GlobalValue *CodeGenModule::GetGlobalValue(StringRef Name) {
535 return getModule().getNamedValue(Name);
538 /// AddGlobalCtor - Add a function to the list that will be called before
540 void CodeGenModule::AddGlobalCtor(llvm::Function * Ctor, int Priority) {
541 // FIXME: Type coercion of void()* types.
542 GlobalCtors.push_back(std::make_pair(Ctor, Priority));
545 /// AddGlobalDtor - Add a function to the list that will be called
546 /// when the module is unloaded.
547 void CodeGenModule::AddGlobalDtor(llvm::Function * Dtor, int Priority) {
548 // FIXME: Type coercion of void()* types.
549 GlobalDtors.push_back(std::make_pair(Dtor, Priority));
552 void CodeGenModule::EmitCtorList(const CtorList &Fns, const char *GlobalName) {
553 // Ctor function type is void()*.
554 llvm::FunctionType* CtorFTy = llvm::FunctionType::get(VoidTy, false);
555 llvm::Type *CtorPFTy = llvm::PointerType::getUnqual(CtorFTy);
557 // Get the type of a ctor entry, { i32, void ()* }.
558 llvm::StructType *CtorStructTy =
559 llvm::StructType::get(Int32Ty, llvm::PointerType::getUnqual(CtorFTy), NULL);
561 // Construct the constructor and destructor arrays.
562 SmallVector<llvm::Constant*, 8> Ctors;
563 for (CtorList::const_iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) {
564 llvm::Constant *S[] = {
565 llvm::ConstantInt::get(Int32Ty, I->second, false),
566 llvm::ConstantExpr::getBitCast(I->first, CtorPFTy)
568 Ctors.push_back(llvm::ConstantStruct::get(CtorStructTy, S));
571 if (!Ctors.empty()) {
572 llvm::ArrayType *AT = llvm::ArrayType::get(CtorStructTy, Ctors.size());
573 new llvm::GlobalVariable(TheModule, AT, false,
574 llvm::GlobalValue::AppendingLinkage,
575 llvm::ConstantArray::get(AT, Ctors),
580 llvm::GlobalValue::LinkageTypes
581 CodeGenModule::getFunctionLinkage(GlobalDecl GD) {
582 const FunctionDecl *D = cast<FunctionDecl>(GD.getDecl());
584 if (isa<CXXDestructorDecl>(D) &&
585 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
587 return llvm::Function::LinkOnceODRLinkage;
589 GVALinkage Linkage = getContext().GetGVALinkageForFunction(D);
591 if (Linkage == GVA_Internal)
592 return llvm::Function::InternalLinkage;
594 if (D->hasAttr<DLLExportAttr>())
595 return llvm::Function::DLLExportLinkage;
597 if (D->hasAttr<WeakAttr>())
598 return llvm::Function::WeakAnyLinkage;
600 // In C99 mode, 'inline' functions are guaranteed to have a strong
601 // definition somewhere else, so we can use available_externally linkage.
602 if (Linkage == GVA_C99Inline)
603 return llvm::Function::AvailableExternallyLinkage;
605 // Note that Apple's kernel linker doesn't support symbol
606 // coalescing, so we need to avoid linkonce and weak linkages there.
607 // Normally, this means we just map to internal, but for explicit
608 // instantiations we'll map to external.
610 // In C++, the compiler has to emit a definition in every translation unit
611 // that references the function. We should use linkonce_odr because
612 // a) if all references in this translation unit are optimized away, we
613 // don't need to codegen it. b) if the function persists, it needs to be
614 // merged with other definitions. c) C++ has the ODR, so we know the
615 // definition is dependable.
616 if (Linkage == GVA_CXXInline || Linkage == GVA_TemplateInstantiation)
617 return !Context.getLangOpts().AppleKext
618 ? llvm::Function::LinkOnceODRLinkage
619 : llvm::Function::InternalLinkage;
621 // An explicit instantiation of a template has weak linkage, since
622 // explicit instantiations can occur in multiple translation units
623 // and must all be equivalent. However, we are not allowed to
624 // throw away these explicit instantiations.
625 if (Linkage == GVA_ExplicitTemplateInstantiation)
626 return !Context.getLangOpts().AppleKext
627 ? llvm::Function::WeakODRLinkage
628 : llvm::Function::ExternalLinkage;
630 // Otherwise, we have strong external linkage.
631 assert(Linkage == GVA_StrongExternal);
632 return llvm::Function::ExternalLinkage;
636 /// SetFunctionDefinitionAttributes - Set attributes for a global.
638 /// FIXME: This is currently only done for aliases and functions, but not for
639 /// variables (these details are set in EmitGlobalVarDefinition for variables).
640 void CodeGenModule::SetFunctionDefinitionAttributes(const FunctionDecl *D,
641 llvm::GlobalValue *GV) {
642 SetCommonAttributes(D, GV);
645 void CodeGenModule::SetLLVMFunctionAttributes(const Decl *D,
646 const CGFunctionInfo &Info,
648 unsigned CallingConv;
649 AttributeListType AttributeList;
650 ConstructAttributeList(Info, D, AttributeList, CallingConv, false);
651 F->setAttributes(llvm::AttributeSet::get(getLLVMContext(), AttributeList));
652 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
655 /// Determines whether the language options require us to model
656 /// unwind exceptions. We treat -fexceptions as mandating this
657 /// except under the fragile ObjC ABI with only ObjC exceptions
658 /// enabled. This means, for example, that C with -fexceptions
660 static bool hasUnwindExceptions(const LangOptions &LangOpts) {
661 // If exceptions are completely disabled, obviously this is false.
662 if (!LangOpts.Exceptions) return false;
664 // If C++ exceptions are enabled, this is true.
665 if (LangOpts.CXXExceptions) return true;
667 // If ObjC exceptions are enabled, this depends on the ABI.
668 if (LangOpts.ObjCExceptions) {
669 return LangOpts.ObjCRuntime.hasUnwindExceptions();
675 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
679 if (CodeGenOpts.UnwindTables)
680 B.addAttribute(llvm::Attribute::UWTable);
682 if (!hasUnwindExceptions(LangOpts))
683 B.addAttribute(llvm::Attribute::NoUnwind);
685 if (D->hasAttr<NakedAttr>()) {
686 // Naked implies noinline: we should not be inlining such functions.
687 B.addAttribute(llvm::Attribute::Naked);
688 B.addAttribute(llvm::Attribute::NoInline);
689 } else if (D->hasAttr<NoInlineAttr>()) {
690 B.addAttribute(llvm::Attribute::NoInline);
691 } else if ((D->hasAttr<AlwaysInlineAttr>() ||
692 D->hasAttr<ForceInlineAttr>()) &&
693 !F->getAttributes().hasAttribute(llvm::AttributeSet::FunctionIndex,
694 llvm::Attribute::NoInline)) {
695 // (noinline wins over always_inline, and we can't specify both in IR)
696 B.addAttribute(llvm::Attribute::AlwaysInline);
699 if (D->hasAttr<ColdAttr>()) {
700 B.addAttribute(llvm::Attribute::OptimizeForSize);
701 B.addAttribute(llvm::Attribute::Cold);
704 if (D->hasAttr<MinSizeAttr>())
705 B.addAttribute(llvm::Attribute::MinSize);
707 if (LangOpts.getStackProtector() == LangOptions::SSPOn)
708 B.addAttribute(llvm::Attribute::StackProtect);
709 else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
710 B.addAttribute(llvm::Attribute::StackProtectReq);
712 // Add sanitizer attributes if function is not blacklisted.
713 if (!SanitizerBlacklist->isIn(*F)) {
714 // When AddressSanitizer is enabled, set SanitizeAddress attribute
715 // unless __attribute__((no_sanitize_address)) is used.
716 if (SanOpts.Address && !D->hasAttr<NoSanitizeAddressAttr>())
717 B.addAttribute(llvm::Attribute::SanitizeAddress);
718 // Same for ThreadSanitizer and __attribute__((no_sanitize_thread))
719 if (SanOpts.Thread && !D->hasAttr<NoSanitizeThreadAttr>()) {
720 B.addAttribute(llvm::Attribute::SanitizeThread);
722 // Same for MemorySanitizer and __attribute__((no_sanitize_memory))
723 if (SanOpts.Memory && !D->hasAttr<NoSanitizeMemoryAttr>())
724 B.addAttribute(llvm::Attribute::SanitizeMemory);
727 F->addAttributes(llvm::AttributeSet::FunctionIndex,
728 llvm::AttributeSet::get(
729 F->getContext(), llvm::AttributeSet::FunctionIndex, B));
731 if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D))
732 F->setUnnamedAddr(true);
733 else if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D))
735 F->setUnnamedAddr(true);
737 unsigned alignment = D->getMaxAlignment() / Context.getCharWidth();
739 F->setAlignment(alignment);
741 // C++ ABI requires 2-byte alignment for member functions.
742 if (F->getAlignment() < 2 && isa<CXXMethodDecl>(D))
746 void CodeGenModule::SetCommonAttributes(const Decl *D,
747 llvm::GlobalValue *GV) {
748 if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
749 setGlobalVisibility(GV, ND);
751 GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
753 if (D->hasAttr<UsedAttr>())
756 if (const SectionAttr *SA = D->getAttr<SectionAttr>())
757 GV->setSection(SA->getName());
759 // Alias cannot have attributes. Filter them here.
760 if (!isa<llvm::GlobalAlias>(GV))
761 getTargetCodeGenInfo().SetTargetAttributes(D, GV, *this);
764 void CodeGenModule::SetInternalFunctionAttributes(const Decl *D,
766 const CGFunctionInfo &FI) {
767 SetLLVMFunctionAttributes(D, FI, F);
768 SetLLVMFunctionAttributesForDefinition(D, F);
770 F->setLinkage(llvm::Function::InternalLinkage);
772 SetCommonAttributes(D, F);
775 void CodeGenModule::SetFunctionAttributes(GlobalDecl GD,
777 bool IsIncompleteFunction) {
778 if (unsigned IID = F->getIntrinsicID()) {
779 // If this is an intrinsic function, set the function's attributes
780 // to the intrinsic's attributes.
781 F->setAttributes(llvm::Intrinsic::getAttributes(getLLVMContext(),
782 (llvm::Intrinsic::ID)IID));
786 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl());
788 if (!IsIncompleteFunction)
789 SetLLVMFunctionAttributes(FD, getTypes().arrangeGlobalDeclaration(GD), F);
791 if (getCXXABI().HasThisReturn(GD)) {
792 assert(!F->arg_empty() &&
793 F->arg_begin()->getType()
794 ->canLosslesslyBitCastTo(F->getReturnType()) &&
795 "unexpected this return");
796 F->addAttribute(1, llvm::Attribute::Returned);
799 // Only a few attributes are set on declarations; these may later be
800 // overridden by a definition.
802 if (FD->hasAttr<DLLImportAttr>()) {
803 F->setLinkage(llvm::Function::DLLImportLinkage);
804 } else if (FD->hasAttr<WeakAttr>() ||
805 FD->isWeakImported()) {
806 // "extern_weak" is overloaded in LLVM; we probably should have
807 // separate linkage types for this.
808 F->setLinkage(llvm::Function::ExternalWeakLinkage);
810 F->setLinkage(llvm::Function::ExternalLinkage);
812 LinkageInfo LV = FD->getLinkageAndVisibility();
813 if (LV.getLinkage() == ExternalLinkage && LV.isVisibilityExplicit()) {
814 F->setVisibility(GetLLVMVisibility(LV.getVisibility()));
818 if (const SectionAttr *SA = FD->getAttr<SectionAttr>())
819 F->setSection(SA->getName());
821 // A replaceable global allocation function does not act like a builtin by
822 // default, only if it is invoked by a new-expression or delete-expression.
823 if (FD->isReplaceableGlobalAllocationFunction())
824 F->addAttribute(llvm::AttributeSet::FunctionIndex,
825 llvm::Attribute::NoBuiltin);
828 void CodeGenModule::AddUsedGlobal(llvm::GlobalValue *GV) {
829 assert(!GV->isDeclaration() &&
830 "Only globals with definition can force usage.");
831 LLVMUsed.push_back(GV);
834 void CodeGenModule::EmitLLVMUsed() {
835 // Don't create llvm.used if there is no need.
836 if (LLVMUsed.empty())
839 // Convert LLVMUsed to what ConstantArray needs.
840 SmallVector<llvm::Constant*, 8> UsedArray;
841 UsedArray.resize(LLVMUsed.size());
842 for (unsigned i = 0, e = LLVMUsed.size(); i != e; ++i) {
844 llvm::ConstantExpr::getBitCast(cast<llvm::Constant>(&*LLVMUsed[i]),
848 if (UsedArray.empty())
850 llvm::ArrayType *ATy = llvm::ArrayType::get(Int8PtrTy, UsedArray.size());
852 llvm::GlobalVariable *GV =
853 new llvm::GlobalVariable(getModule(), ATy, false,
854 llvm::GlobalValue::AppendingLinkage,
855 llvm::ConstantArray::get(ATy, UsedArray),
858 GV->setSection("llvm.metadata");
861 void CodeGenModule::AppendLinkerOptions(StringRef Opts) {
862 llvm::Value *MDOpts = llvm::MDString::get(getLLVMContext(), Opts);
863 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
866 void CodeGenModule::AddDetectMismatch(StringRef Name, StringRef Value) {
867 llvm::SmallString<32> Opt;
868 getTargetCodeGenInfo().getDetectMismatchOption(Name, Value, Opt);
869 llvm::Value *MDOpts = llvm::MDString::get(getLLVMContext(), Opt);
870 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
873 void CodeGenModule::AddDependentLib(StringRef Lib) {
874 llvm::SmallString<24> Opt;
875 getTargetCodeGenInfo().getDependentLibraryOption(Lib, Opt);
876 llvm::Value *MDOpts = llvm::MDString::get(getLLVMContext(), Opt);
877 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
880 /// \brief Add link options implied by the given module, including modules
881 /// it depends on, using a postorder walk.
882 static void addLinkOptionsPostorder(CodeGenModule &CGM,
884 SmallVectorImpl<llvm::Value *> &Metadata,
885 llvm::SmallPtrSet<Module *, 16> &Visited) {
886 // Import this module's parent.
887 if (Mod->Parent && Visited.insert(Mod->Parent)) {
888 addLinkOptionsPostorder(CGM, Mod->Parent, Metadata, Visited);
891 // Import this module's dependencies.
892 for (unsigned I = Mod->Imports.size(); I > 0; --I) {
893 if (Visited.insert(Mod->Imports[I-1]))
894 addLinkOptionsPostorder(CGM, Mod->Imports[I-1], Metadata, Visited);
897 // Add linker options to link against the libraries/frameworks
898 // described by this module.
899 llvm::LLVMContext &Context = CGM.getLLVMContext();
900 for (unsigned I = Mod->LinkLibraries.size(); I > 0; --I) {
901 // Link against a framework. Frameworks are currently Darwin only, so we
902 // don't to ask TargetCodeGenInfo for the spelling of the linker option.
903 if (Mod->LinkLibraries[I-1].IsFramework) {
904 llvm::Value *Args[2] = {
905 llvm::MDString::get(Context, "-framework"),
906 llvm::MDString::get(Context, Mod->LinkLibraries[I-1].Library)
909 Metadata.push_back(llvm::MDNode::get(Context, Args));
913 // Link against a library.
914 llvm::SmallString<24> Opt;
915 CGM.getTargetCodeGenInfo().getDependentLibraryOption(
916 Mod->LinkLibraries[I-1].Library, Opt);
917 llvm::Value *OptString = llvm::MDString::get(Context, Opt);
918 Metadata.push_back(llvm::MDNode::get(Context, OptString));
922 void CodeGenModule::EmitModuleLinkOptions() {
923 // Collect the set of all of the modules we want to visit to emit link
924 // options, which is essentially the imported modules and all of their
925 // non-explicit child modules.
926 llvm::SetVector<clang::Module *> LinkModules;
927 llvm::SmallPtrSet<clang::Module *, 16> Visited;
928 SmallVector<clang::Module *, 16> Stack;
930 // Seed the stack with imported modules.
931 for (llvm::SetVector<clang::Module *>::iterator M = ImportedModules.begin(),
932 MEnd = ImportedModules.end();
934 if (Visited.insert(*M))
938 // Find all of the modules to import, making a little effort to prune
940 while (!Stack.empty()) {
941 clang::Module *Mod = Stack.pop_back_val();
943 bool AnyChildren = false;
945 // Visit the submodules of this module.
946 for (clang::Module::submodule_iterator Sub = Mod->submodule_begin(),
947 SubEnd = Mod->submodule_end();
948 Sub != SubEnd; ++Sub) {
949 // Skip explicit children; they need to be explicitly imported to be
951 if ((*Sub)->IsExplicit)
954 if (Visited.insert(*Sub)) {
955 Stack.push_back(*Sub);
960 // We didn't find any children, so add this module to the list of
961 // modules to link against.
963 LinkModules.insert(Mod);
967 // Add link options for all of the imported modules in reverse topological
968 // order. We don't do anything to try to order import link flags with respect
969 // to linker options inserted by things like #pragma comment().
970 SmallVector<llvm::Value *, 16> MetadataArgs;
972 for (llvm::SetVector<clang::Module *>::iterator M = LinkModules.begin(),
973 MEnd = LinkModules.end();
975 if (Visited.insert(*M))
976 addLinkOptionsPostorder(*this, *M, MetadataArgs, Visited);
978 std::reverse(MetadataArgs.begin(), MetadataArgs.end());
979 LinkerOptionsMetadata.append(MetadataArgs.begin(), MetadataArgs.end());
981 // Add the linker options metadata flag.
982 getModule().addModuleFlag(llvm::Module::AppendUnique, "Linker Options",
983 llvm::MDNode::get(getLLVMContext(),
984 LinkerOptionsMetadata));
987 void CodeGenModule::EmitDeferred() {
988 // Emit code for any potentially referenced deferred decls. Since a
989 // previously unused static decl may become used during the generation of code
990 // for a static function, iterate until no changes are made.
993 if (!DeferredVTables.empty()) {
994 EmitDeferredVTables();
996 // Emitting a v-table doesn't directly cause more v-tables to
997 // become deferred, although it can cause functions to be
998 // emitted that then need those v-tables.
999 assert(DeferredVTables.empty());
1002 // Stop if we're out of both deferred v-tables and deferred declarations.
1003 if (DeferredDeclsToEmit.empty()) break;
1005 GlobalDecl D = DeferredDeclsToEmit.back();
1006 DeferredDeclsToEmit.pop_back();
1008 // Check to see if we've already emitted this. This is necessary
1009 // for a couple of reasons: first, decls can end up in the
1010 // deferred-decls queue multiple times, and second, decls can end
1011 // up with definitions in unusual ways (e.g. by an extern inline
1012 // function acquiring a strong function redefinition). Just
1013 // ignore these cases.
1015 // TODO: That said, looking this up multiple times is very wasteful.
1016 StringRef Name = getMangledName(D);
1017 llvm::GlobalValue *CGRef = GetGlobalValue(Name);
1018 assert(CGRef && "Deferred decl wasn't referenced?");
1020 if (!CGRef->isDeclaration())
1023 // GlobalAlias::isDeclaration() defers to the aliasee, but for our
1024 // purposes an alias counts as a definition.
1025 if (isa<llvm::GlobalAlias>(CGRef))
1028 // Otherwise, emit the definition and move on to the next one.
1029 EmitGlobalDefinition(D);
1033 void CodeGenModule::EmitGlobalAnnotations() {
1034 if (Annotations.empty())
1037 // Create a new global variable for the ConstantStruct in the Module.
1038 llvm::Constant *Array = llvm::ConstantArray::get(llvm::ArrayType::get(
1039 Annotations[0]->getType(), Annotations.size()), Annotations);
1040 llvm::GlobalValue *gv = new llvm::GlobalVariable(getModule(),
1041 Array->getType(), false, llvm::GlobalValue::AppendingLinkage, Array,
1042 "llvm.global.annotations");
1043 gv->setSection(AnnotationSection);
1046 llvm::Constant *CodeGenModule::EmitAnnotationString(StringRef Str) {
1047 llvm::Constant *&AStr = AnnotationStrings[Str];
1051 // Not found yet, create a new global.
1052 llvm::Constant *s = llvm::ConstantDataArray::getString(getLLVMContext(), Str);
1053 llvm::GlobalValue *gv = new llvm::GlobalVariable(getModule(), s->getType(),
1054 true, llvm::GlobalValue::PrivateLinkage, s, ".str");
1055 gv->setSection(AnnotationSection);
1056 gv->setUnnamedAddr(true);
1061 llvm::Constant *CodeGenModule::EmitAnnotationUnit(SourceLocation Loc) {
1062 SourceManager &SM = getContext().getSourceManager();
1063 PresumedLoc PLoc = SM.getPresumedLoc(Loc);
1065 return EmitAnnotationString(PLoc.getFilename());
1066 return EmitAnnotationString(SM.getBufferName(Loc));
1069 llvm::Constant *CodeGenModule::EmitAnnotationLineNo(SourceLocation L) {
1070 SourceManager &SM = getContext().getSourceManager();
1071 PresumedLoc PLoc = SM.getPresumedLoc(L);
1072 unsigned LineNo = PLoc.isValid() ? PLoc.getLine() :
1073 SM.getExpansionLineNumber(L);
1074 return llvm::ConstantInt::get(Int32Ty, LineNo);
1077 llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV,
1078 const AnnotateAttr *AA,
1080 // Get the globals for file name, annotation, and the line number.
1081 llvm::Constant *AnnoGV = EmitAnnotationString(AA->getAnnotation()),
1082 *UnitGV = EmitAnnotationUnit(L),
1083 *LineNoCst = EmitAnnotationLineNo(L);
1085 // Create the ConstantStruct for the global annotation.
1086 llvm::Constant *Fields[4] = {
1087 llvm::ConstantExpr::getBitCast(GV, Int8PtrTy),
1088 llvm::ConstantExpr::getBitCast(AnnoGV, Int8PtrTy),
1089 llvm::ConstantExpr::getBitCast(UnitGV, Int8PtrTy),
1092 return llvm::ConstantStruct::getAnon(Fields);
1095 void CodeGenModule::AddGlobalAnnotations(const ValueDecl *D,
1096 llvm::GlobalValue *GV) {
1097 assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute");
1098 // Get the struct elements for these annotations.
1099 for (specific_attr_iterator<AnnotateAttr>
1100 ai = D->specific_attr_begin<AnnotateAttr>(),
1101 ae = D->specific_attr_end<AnnotateAttr>(); ai != ae; ++ai)
1102 Annotations.push_back(EmitAnnotateAttr(GV, *ai, D->getLocation()));
1105 bool CodeGenModule::MayDeferGeneration(const ValueDecl *Global) {
1106 // Never defer when EmitAllDecls is specified.
1107 if (LangOpts.EmitAllDecls)
1110 return !getContext().DeclMustBeEmitted(Global);
1113 llvm::Constant *CodeGenModule::GetAddrOfUuidDescriptor(
1114 const CXXUuidofExpr* E) {
1115 // Sema has verified that IIDSource has a __declspec(uuid()), and that its
1117 StringRef Uuid = E->getUuidAsStringRef(Context);
1118 std::string Name = "_GUID_" + Uuid.lower();
1119 std::replace(Name.begin(), Name.end(), '-', '_');
1121 // Look for an existing global.
1122 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name))
1125 llvm::Constant *Init = EmitUuidofInitializer(Uuid, E->getType());
1126 assert(Init && "failed to initialize as constant");
1128 llvm::GlobalVariable *GV = new llvm::GlobalVariable(
1129 getModule(), Init->getType(),
1130 /*isConstant=*/true, llvm::GlobalValue::LinkOnceODRLinkage, Init, Name);
1134 llvm::Constant *CodeGenModule::GetWeakRefReference(const ValueDecl *VD) {
1135 const AliasAttr *AA = VD->getAttr<AliasAttr>();
1136 assert(AA && "No alias?");
1138 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(VD->getType());
1140 // See if there is already something with the target's name in the module.
1141 llvm::GlobalValue *Entry = GetGlobalValue(AA->getAliasee());
1143 unsigned AS = getContext().getTargetAddressSpace(VD->getType());
1144 return llvm::ConstantExpr::getBitCast(Entry, DeclTy->getPointerTo(AS));
1147 llvm::Constant *Aliasee;
1148 if (isa<llvm::FunctionType>(DeclTy))
1149 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy,
1150 GlobalDecl(cast<FunctionDecl>(VD)),
1151 /*ForVTable=*/false);
1153 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(),
1154 llvm::PointerType::getUnqual(DeclTy), 0);
1156 llvm::GlobalValue* F = cast<llvm::GlobalValue>(Aliasee);
1157 F->setLinkage(llvm::Function::ExternalWeakLinkage);
1158 WeakRefReferences.insert(F);
1163 void CodeGenModule::EmitGlobal(GlobalDecl GD) {
1164 const ValueDecl *Global = cast<ValueDecl>(GD.getDecl());
1166 // Weak references don't produce any output by themselves.
1167 if (Global->hasAttr<WeakRefAttr>())
1170 // If this is an alias definition (which otherwise looks like a declaration)
1172 if (Global->hasAttr<AliasAttr>())
1173 return EmitAliasDefinition(GD);
1175 // If this is CUDA, be selective about which declarations we emit.
1176 if (LangOpts.CUDA) {
1177 if (CodeGenOpts.CUDAIsDevice) {
1178 if (!Global->hasAttr<CUDADeviceAttr>() &&
1179 !Global->hasAttr<CUDAGlobalAttr>() &&
1180 !Global->hasAttr<CUDAConstantAttr>() &&
1181 !Global->hasAttr<CUDASharedAttr>())
1184 if (!Global->hasAttr<CUDAHostAttr>() && (
1185 Global->hasAttr<CUDADeviceAttr>() ||
1186 Global->hasAttr<CUDAConstantAttr>() ||
1187 Global->hasAttr<CUDASharedAttr>()))
1192 // Ignore declarations, they will be emitted on their first use.
1193 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Global)) {
1194 // Forward declarations are emitted lazily on first use.
1195 if (!FD->doesThisDeclarationHaveABody()) {
1196 if (!FD->doesDeclarationForceExternallyVisibleDefinition())
1199 const FunctionDecl *InlineDefinition = 0;
1200 FD->getBody(InlineDefinition);
1202 StringRef MangledName = getMangledName(GD);
1203 DeferredDecls.erase(MangledName);
1204 EmitGlobalDefinition(InlineDefinition);
1208 const VarDecl *VD = cast<VarDecl>(Global);
1209 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global.");
1211 if (VD->isThisDeclarationADefinition() != VarDecl::Definition)
1215 // Defer code generation when possible if this is a static definition, inline
1216 // function etc. These we only want to emit if they are used.
1217 if (!MayDeferGeneration(Global)) {
1218 // Emit the definition if it can't be deferred.
1219 EmitGlobalDefinition(GD);
1223 // If we're deferring emission of a C++ variable with an
1224 // initializer, remember the order in which it appeared in the file.
1225 if (getLangOpts().CPlusPlus && isa<VarDecl>(Global) &&
1226 cast<VarDecl>(Global)->hasInit()) {
1227 DelayedCXXInitPosition[Global] = CXXGlobalInits.size();
1228 CXXGlobalInits.push_back(0);
1231 // If the value has already been used, add it directly to the
1232 // DeferredDeclsToEmit list.
1233 StringRef MangledName = getMangledName(GD);
1234 if (GetGlobalValue(MangledName))
1235 DeferredDeclsToEmit.push_back(GD);
1237 // Otherwise, remember that we saw a deferred decl with this name. The
1238 // first use of the mangled name will cause it to move into
1239 // DeferredDeclsToEmit.
1240 DeferredDecls[MangledName] = GD;
1245 struct FunctionIsDirectlyRecursive :
1246 public RecursiveASTVisitor<FunctionIsDirectlyRecursive> {
1247 const StringRef Name;
1248 const Builtin::Context &BI;
1250 FunctionIsDirectlyRecursive(StringRef N, const Builtin::Context &C) :
1251 Name(N), BI(C), Result(false) {
1253 typedef RecursiveASTVisitor<FunctionIsDirectlyRecursive> Base;
1255 bool TraverseCallExpr(CallExpr *E) {
1256 const FunctionDecl *FD = E->getDirectCallee();
1259 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>();
1260 if (Attr && Name == Attr->getLabel()) {
1264 unsigned BuiltinID = FD->getBuiltinID();
1267 StringRef BuiltinName = BI.GetName(BuiltinID);
1268 if (BuiltinName.startswith("__builtin_") &&
1269 Name == BuiltinName.slice(strlen("__builtin_"), StringRef::npos)) {
1278 // isTriviallyRecursive - Check if this function calls another
1279 // decl that, because of the asm attribute or the other decl being a builtin,
1280 // ends up pointing to itself.
1282 CodeGenModule::isTriviallyRecursive(const FunctionDecl *FD) {
1284 if (getCXXABI().getMangleContext().shouldMangleDeclName(FD)) {
1285 // asm labels are a special kind of mangling we have to support.
1286 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>();
1289 Name = Attr->getLabel();
1291 Name = FD->getName();
1294 FunctionIsDirectlyRecursive Walker(Name, Context.BuiltinInfo);
1295 Walker.TraverseFunctionDecl(const_cast<FunctionDecl*>(FD));
1296 return Walker.Result;
1300 CodeGenModule::shouldEmitFunction(GlobalDecl GD) {
1301 if (getFunctionLinkage(GD) != llvm::Function::AvailableExternallyLinkage)
1303 const FunctionDecl *F = cast<FunctionDecl>(GD.getDecl());
1304 if (CodeGenOpts.OptimizationLevel == 0 &&
1305 !F->hasAttr<AlwaysInlineAttr>() && !F->hasAttr<ForceInlineAttr>())
1307 // PR9614. Avoid cases where the source code is lying to us. An available
1308 // externally function should have an equivalent function somewhere else,
1309 // but a function that calls itself is clearly not equivalent to the real
1311 // This happens in glibc's btowc and in some configure checks.
1312 return !isTriviallyRecursive(F);
1315 /// If the type for the method's class was generated by
1316 /// CGDebugInfo::createContextChain(), the cache contains only a
1317 /// limited DIType without any declarations. Since EmitFunctionStart()
1318 /// needs to find the canonical declaration for each method, we need
1319 /// to construct the complete type prior to emitting the method.
1320 void CodeGenModule::CompleteDIClassType(const CXXMethodDecl* D) {
1321 if (!D->isInstance())
1324 if (CGDebugInfo *DI = getModuleDebugInfo())
1325 if (getCodeGenOpts().getDebugInfo() >= CodeGenOptions::LimitedDebugInfo) {
1326 const PointerType *ThisPtr =
1327 cast<PointerType>(D->getThisType(getContext()));
1328 DI->getOrCreateRecordType(ThisPtr->getPointeeType(), D->getLocation());
1332 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD) {
1333 const ValueDecl *D = cast<ValueDecl>(GD.getDecl());
1335 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(),
1336 Context.getSourceManager(),
1337 "Generating code for declaration");
1339 if (isa<FunctionDecl>(D)) {
1340 // At -O0, don't generate IR for functions with available_externally
1342 if (!shouldEmitFunction(GD))
1345 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
1346 CompleteDIClassType(Method);
1347 // Make sure to emit the definition(s) before we emit the thunks.
1348 // This is necessary for the generation of certain thunks.
1349 if (const CXXConstructorDecl *CD = dyn_cast<CXXConstructorDecl>(Method))
1350 EmitCXXConstructor(CD, GD.getCtorType());
1351 else if (const CXXDestructorDecl *DD =dyn_cast<CXXDestructorDecl>(Method))
1352 EmitCXXDestructor(DD, GD.getDtorType());
1354 EmitGlobalFunctionDefinition(GD);
1356 if (Method->isVirtual())
1357 getVTables().EmitThunks(GD);
1362 return EmitGlobalFunctionDefinition(GD);
1365 if (const VarDecl *VD = dyn_cast<VarDecl>(D))
1366 return EmitGlobalVarDefinition(VD);
1368 llvm_unreachable("Invalid argument to EmitGlobalDefinition()");
1371 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the
1372 /// module, create and return an llvm Function with the specified type. If there
1373 /// is something in the module with the specified name, return it potentially
1374 /// bitcasted to the right type.
1376 /// If D is non-null, it specifies a decl that correspond to this. This is used
1377 /// to set the attributes on the function when it is first created.
1379 CodeGenModule::GetOrCreateLLVMFunction(StringRef MangledName,
1381 GlobalDecl GD, bool ForVTable,
1382 llvm::AttributeSet ExtraAttrs) {
1383 const Decl *D = GD.getDecl();
1385 // Lookup the entry, lazily creating it if necessary.
1386 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
1388 if (WeakRefReferences.erase(Entry)) {
1389 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D);
1390 if (FD && !FD->hasAttr<WeakAttr>())
1391 Entry->setLinkage(llvm::Function::ExternalLinkage);
1394 if (Entry->getType()->getElementType() == Ty)
1397 // Make sure the result is of the correct type.
1398 return llvm::ConstantExpr::getBitCast(Entry, Ty->getPointerTo());
1401 // All MSVC dtors other than the base dtor are linkonce_odr and delegate to
1402 // each other bottoming out with the base dtor. Therefore we emit non-base
1403 // dtors on usage, even if there is no dtor definition in the TU.
1404 if (D && isa<CXXDestructorDecl>(D) &&
1405 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
1407 DeferredDeclsToEmit.push_back(GD);
1409 // This function doesn't have a complete type (for example, the return
1410 // type is an incomplete struct). Use a fake type instead, and make
1411 // sure not to try to set attributes.
1412 bool IsIncompleteFunction = false;
1414 llvm::FunctionType *FTy;
1415 if (isa<llvm::FunctionType>(Ty)) {
1416 FTy = cast<llvm::FunctionType>(Ty);
1418 FTy = llvm::FunctionType::get(VoidTy, false);
1419 IsIncompleteFunction = true;
1422 llvm::Function *F = llvm::Function::Create(FTy,
1423 llvm::Function::ExternalLinkage,
1424 MangledName, &getModule());
1425 assert(F->getName() == MangledName && "name was uniqued!");
1427 SetFunctionAttributes(GD, F, IsIncompleteFunction);
1428 if (ExtraAttrs.hasAttributes(llvm::AttributeSet::FunctionIndex)) {
1429 llvm::AttrBuilder B(ExtraAttrs, llvm::AttributeSet::FunctionIndex);
1430 F->addAttributes(llvm::AttributeSet::FunctionIndex,
1431 llvm::AttributeSet::get(VMContext,
1432 llvm::AttributeSet::FunctionIndex,
1436 // This is the first use or definition of a mangled name. If there is a
1437 // deferred decl with this name, remember that we need to emit it at the end
1439 llvm::StringMap<GlobalDecl>::iterator DDI = DeferredDecls.find(MangledName);
1440 if (DDI != DeferredDecls.end()) {
1441 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit
1442 // list, and remove it from DeferredDecls (since we don't need it anymore).
1443 DeferredDeclsToEmit.push_back(DDI->second);
1444 DeferredDecls.erase(DDI);
1446 // Otherwise, if this is a sized deallocation function, emit a weak definition
1447 // for it at the end of the translation unit.
1448 } else if (D && cast<FunctionDecl>(D)
1449 ->getCorrespondingUnsizedGlobalDeallocationFunction()) {
1450 DeferredDeclsToEmit.push_back(GD);
1452 // Otherwise, there are cases we have to worry about where we're
1453 // using a declaration for which we must emit a definition but where
1454 // we might not find a top-level definition:
1455 // - member functions defined inline in their classes
1456 // - friend functions defined inline in some class
1457 // - special member functions with implicit definitions
1458 // If we ever change our AST traversal to walk into class methods,
1459 // this will be unnecessary.
1461 // We also don't emit a definition for a function if it's going to be an entry
1462 // in a vtable, unless it's already marked as used.
1463 } else if (getLangOpts().CPlusPlus && D) {
1464 // Look for a declaration that's lexically in a record.
1465 const FunctionDecl *FD = cast<FunctionDecl>(D);
1466 FD = FD->getMostRecentDecl();
1468 if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) {
1469 if (FD->isImplicit() && !ForVTable) {
1470 assert(FD->isUsed() && "Sema didn't mark implicit function as used!");
1471 DeferredDeclsToEmit.push_back(GD.getWithDecl(FD));
1473 } else if (FD->doesThisDeclarationHaveABody()) {
1474 DeferredDeclsToEmit.push_back(GD.getWithDecl(FD));
1478 FD = FD->getPreviousDecl();
1482 // Make sure the result is of the requested type.
1483 if (!IsIncompleteFunction) {
1484 assert(F->getType()->getElementType() == Ty);
1488 llvm::Type *PTy = llvm::PointerType::getUnqual(Ty);
1489 return llvm::ConstantExpr::getBitCast(F, PTy);
1492 /// GetAddrOfFunction - Return the address of the given function. If Ty is
1493 /// non-null, then this function will use the specified type if it has to
1494 /// create it (this occurs when we see a definition of the function).
1495 llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD,
1498 // If there was no specific requested type, just convert it now.
1500 Ty = getTypes().ConvertType(cast<ValueDecl>(GD.getDecl())->getType());
1502 StringRef MangledName = getMangledName(GD);
1503 return GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable);
1506 /// CreateRuntimeFunction - Create a new runtime function with the specified
1509 CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy,
1511 llvm::AttributeSet ExtraAttrs) {
1513 = GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false,
1515 if (llvm::Function *F = dyn_cast<llvm::Function>(C))
1517 F->setCallingConv(getRuntimeCC());
1521 /// isTypeConstant - Determine whether an object of this type can be emitted
1524 /// If ExcludeCtor is true, the duration when the object's constructor runs
1525 /// will not be considered. The caller will need to verify that the object is
1526 /// not written to during its construction.
1527 bool CodeGenModule::isTypeConstant(QualType Ty, bool ExcludeCtor) {
1528 if (!Ty.isConstant(Context) && !Ty->isReferenceType())
1531 if (Context.getLangOpts().CPlusPlus) {
1532 if (const CXXRecordDecl *Record
1533 = Context.getBaseElementType(Ty)->getAsCXXRecordDecl())
1534 return ExcludeCtor && !Record->hasMutableFields() &&
1535 Record->hasTrivialDestructor();
1541 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module,
1542 /// create and return an llvm GlobalVariable with the specified type. If there
1543 /// is something in the module with the specified name, return it potentially
1544 /// bitcasted to the right type.
1546 /// If D is non-null, it specifies a decl that correspond to this. This is used
1547 /// to set the attributes on the global when it is first created.
1549 CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName,
1550 llvm::PointerType *Ty,
1553 // Lookup the entry, lazily creating it if necessary.
1554 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
1556 if (WeakRefReferences.erase(Entry)) {
1557 if (D && !D->hasAttr<WeakAttr>())
1558 Entry->setLinkage(llvm::Function::ExternalLinkage);
1562 Entry->setUnnamedAddr(true);
1564 if (Entry->getType() == Ty)
1567 // Make sure the result is of the correct type.
1568 if (Entry->getType()->getAddressSpace() != Ty->getAddressSpace())
1569 return llvm::ConstantExpr::getAddrSpaceCast(Entry, Ty);
1571 return llvm::ConstantExpr::getBitCast(Entry, Ty);
1574 // This is the first use or definition of a mangled name. If there is a
1575 // deferred decl with this name, remember that we need to emit it at the end
1577 llvm::StringMap<GlobalDecl>::iterator DDI = DeferredDecls.find(MangledName);
1578 if (DDI != DeferredDecls.end()) {
1579 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit
1580 // list, and remove it from DeferredDecls (since we don't need it anymore).
1581 DeferredDeclsToEmit.push_back(DDI->second);
1582 DeferredDecls.erase(DDI);
1585 unsigned AddrSpace = GetGlobalVarAddressSpace(D, Ty->getAddressSpace());
1586 llvm::GlobalVariable *GV =
1587 new llvm::GlobalVariable(getModule(), Ty->getElementType(), false,
1588 llvm::GlobalValue::ExternalLinkage,
1590 llvm::GlobalVariable::NotThreadLocal, AddrSpace);
1592 // Handle things which are present even on external declarations.
1594 // FIXME: This code is overly simple and should be merged with other global
1596 GV->setConstant(isTypeConstant(D->getType(), false));
1598 // Set linkage and visibility in case we never see a definition.
1599 LinkageInfo LV = D->getLinkageAndVisibility();
1600 if (LV.getLinkage() != ExternalLinkage) {
1601 // Don't set internal linkage on declarations.
1603 if (D->hasAttr<DLLImportAttr>())
1604 GV->setLinkage(llvm::GlobalValue::DLLImportLinkage);
1605 else if (D->hasAttr<WeakAttr>() || D->isWeakImported())
1606 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage);
1608 // Set visibility on a declaration only if it's explicit.
1609 if (LV.isVisibilityExplicit())
1610 GV->setVisibility(GetLLVMVisibility(LV.getVisibility()));
1613 if (D->getTLSKind()) {
1614 if (D->getTLSKind() == VarDecl::TLS_Dynamic)
1615 CXXThreadLocals.push_back(std::make_pair(D, GV));
1619 // If required by the ABI, treat declarations of static data members with
1620 // inline initializers as definitions.
1621 if (getCXXABI().isInlineInitializedStaticDataMemberLinkOnce() &&
1622 D->isStaticDataMember() && D->hasInit() &&
1623 !D->isThisDeclarationADefinition())
1624 EmitGlobalVarDefinition(D);
1627 if (AddrSpace != Ty->getAddressSpace())
1628 return llvm::ConstantExpr::getAddrSpaceCast(GV, Ty);
1634 llvm::GlobalVariable *
1635 CodeGenModule::CreateOrReplaceCXXRuntimeVariable(StringRef Name,
1637 llvm::GlobalValue::LinkageTypes Linkage) {
1638 llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name);
1639 llvm::GlobalVariable *OldGV = 0;
1643 // Check if the variable has the right type.
1644 if (GV->getType()->getElementType() == Ty)
1647 // Because C++ name mangling, the only way we can end up with an already
1648 // existing global with the same name is if it has been declared extern "C".
1649 assert(GV->isDeclaration() && "Declaration has wrong type!");
1653 // Create a new variable.
1654 GV = new llvm::GlobalVariable(getModule(), Ty, /*isConstant=*/true,
1658 // Replace occurrences of the old variable if needed.
1659 GV->takeName(OldGV);
1661 if (!OldGV->use_empty()) {
1662 llvm::Constant *NewPtrForOldDecl =
1663 llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
1664 OldGV->replaceAllUsesWith(NewPtrForOldDecl);
1667 OldGV->eraseFromParent();
1673 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the
1674 /// given global variable. If Ty is non-null and if the global doesn't exist,
1675 /// then it will be created with the specified type instead of whatever the
1676 /// normal requested type would be.
1677 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D,
1679 assert(D->hasGlobalStorage() && "Not a global variable");
1680 QualType ASTTy = D->getType();
1682 Ty = getTypes().ConvertTypeForMem(ASTTy);
1684 llvm::PointerType *PTy =
1685 llvm::PointerType::get(Ty, getContext().getTargetAddressSpace(ASTTy));
1687 StringRef MangledName = getMangledName(D);
1688 return GetOrCreateLLVMGlobal(MangledName, PTy, D);
1691 /// CreateRuntimeVariable - Create a new runtime global variable with the
1692 /// specified type and name.
1694 CodeGenModule::CreateRuntimeVariable(llvm::Type *Ty,
1696 return GetOrCreateLLVMGlobal(Name, llvm::PointerType::getUnqual(Ty), 0,
1700 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) {
1701 assert(!D->getInit() && "Cannot emit definite definitions here!");
1703 if (MayDeferGeneration(D)) {
1704 // If we have not seen a reference to this variable yet, place it
1705 // into the deferred declarations table to be emitted if needed
1707 StringRef MangledName = getMangledName(D);
1708 if (!GetGlobalValue(MangledName)) {
1709 DeferredDecls[MangledName] = D;
1714 // The tentative definition is the only definition.
1715 EmitGlobalVarDefinition(D);
1718 CharUnits CodeGenModule::GetTargetTypeStoreSize(llvm::Type *Ty) const {
1719 return Context.toCharUnitsFromBits(
1720 TheDataLayout.getTypeStoreSizeInBits(Ty));
1723 unsigned CodeGenModule::GetGlobalVarAddressSpace(const VarDecl *D,
1724 unsigned AddrSpace) {
1725 if (LangOpts.CUDA && CodeGenOpts.CUDAIsDevice) {
1726 if (D->hasAttr<CUDAConstantAttr>())
1727 AddrSpace = getContext().getTargetAddressSpace(LangAS::cuda_constant);
1728 else if (D->hasAttr<CUDASharedAttr>())
1729 AddrSpace = getContext().getTargetAddressSpace(LangAS::cuda_shared);
1731 AddrSpace = getContext().getTargetAddressSpace(LangAS::cuda_device);
1737 template<typename SomeDecl>
1738 void CodeGenModule::MaybeHandleStaticInExternC(const SomeDecl *D,
1739 llvm::GlobalValue *GV) {
1740 if (!getLangOpts().CPlusPlus)
1743 // Must have 'used' attribute, or else inline assembly can't rely on
1744 // the name existing.
1745 if (!D->template hasAttr<UsedAttr>())
1748 // Must have internal linkage and an ordinary name.
1749 if (!D->getIdentifier() || D->getFormalLinkage() != InternalLinkage)
1752 // Must be in an extern "C" context. Entities declared directly within
1753 // a record are not extern "C" even if the record is in such a context.
1754 const SomeDecl *First = D->getFirstDecl();
1755 if (First->getDeclContext()->isRecord() || !First->isInExternCContext())
1758 // OK, this is an internal linkage entity inside an extern "C" linkage
1759 // specification. Make a note of that so we can give it the "expected"
1760 // mangled name if nothing else is using that name.
1761 std::pair<StaticExternCMap::iterator, bool> R =
1762 StaticExternCValues.insert(std::make_pair(D->getIdentifier(), GV));
1764 // If we have multiple internal linkage entities with the same name
1765 // in extern "C" regions, none of them gets that name.
1767 R.first->second = 0;
1770 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
1771 llvm::Constant *Init = 0;
1772 QualType ASTTy = D->getType();
1773 CXXRecordDecl *RD = ASTTy->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
1774 bool NeedsGlobalCtor = false;
1775 bool NeedsGlobalDtor = RD && !RD->hasTrivialDestructor();
1777 const VarDecl *InitDecl;
1778 const Expr *InitExpr = D->getAnyInitializer(InitDecl);
1781 // This is a tentative definition; tentative definitions are
1782 // implicitly initialized with { 0 }.
1784 // Note that tentative definitions are only emitted at the end of
1785 // a translation unit, so they should never have incomplete
1786 // type. In addition, EmitTentativeDefinition makes sure that we
1787 // never attempt to emit a tentative definition if a real one
1788 // exists. A use may still exists, however, so we still may need
1790 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type");
1791 Init = EmitNullConstant(D->getType());
1793 initializedGlobalDecl = GlobalDecl(D);
1794 Init = EmitConstantInit(*InitDecl);
1797 QualType T = InitExpr->getType();
1798 if (D->getType()->isReferenceType())
1801 if (getLangOpts().CPlusPlus) {
1802 Init = EmitNullConstant(T);
1803 NeedsGlobalCtor = true;
1805 ErrorUnsupported(D, "static initializer");
1806 Init = llvm::UndefValue::get(getTypes().ConvertType(T));
1809 // We don't need an initializer, so remove the entry for the delayed
1810 // initializer position (just in case this entry was delayed) if we
1811 // also don't need to register a destructor.
1812 if (getLangOpts().CPlusPlus && !NeedsGlobalDtor)
1813 DelayedCXXInitPosition.erase(D);
1817 llvm::Type* InitType = Init->getType();
1818 llvm::Constant *Entry = GetAddrOfGlobalVar(D, InitType);
1820 // Strip off a bitcast if we got one back.
1821 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) {
1822 assert(CE->getOpcode() == llvm::Instruction::BitCast ||
1823 CE->getOpcode() == llvm::Instruction::AddrSpaceCast ||
1824 // All zero index gep.
1825 CE->getOpcode() == llvm::Instruction::GetElementPtr);
1826 Entry = CE->getOperand(0);
1829 // Entry is now either a Function or GlobalVariable.
1830 llvm::GlobalVariable *GV = dyn_cast<llvm::GlobalVariable>(Entry);
1832 // We have a definition after a declaration with the wrong type.
1833 // We must make a new GlobalVariable* and update everything that used OldGV
1834 // (a declaration or tentative definition) with the new GlobalVariable*
1835 // (which will be a definition).
1837 // This happens if there is a prototype for a global (e.g.
1838 // "extern int x[];") and then a definition of a different type (e.g.
1839 // "int x[10];"). This also happens when an initializer has a different type
1840 // from the type of the global (this happens with unions).
1842 GV->getType()->getElementType() != InitType ||
1843 GV->getType()->getAddressSpace() !=
1844 GetGlobalVarAddressSpace(D, getContext().getTargetAddressSpace(ASTTy))) {
1846 // Move the old entry aside so that we'll create a new one.
1847 Entry->setName(StringRef());
1849 // Make a new global with the correct type, this is now guaranteed to work.
1850 GV = cast<llvm::GlobalVariable>(GetAddrOfGlobalVar(D, InitType));
1852 // Replace all uses of the old global with the new global
1853 llvm::Constant *NewPtrForOldDecl =
1854 llvm::ConstantExpr::getBitCast(GV, Entry->getType());
1855 Entry->replaceAllUsesWith(NewPtrForOldDecl);
1857 // Erase the old global, since it is no longer used.
1858 cast<llvm::GlobalValue>(Entry)->eraseFromParent();
1861 MaybeHandleStaticInExternC(D, GV);
1863 if (D->hasAttr<AnnotateAttr>())
1864 AddGlobalAnnotations(D, GV);
1866 GV->setInitializer(Init);
1868 // If it is safe to mark the global 'constant', do so now.
1869 GV->setConstant(!NeedsGlobalCtor && !NeedsGlobalDtor &&
1870 isTypeConstant(D->getType(), true));
1872 GV->setAlignment(getContext().getDeclAlign(D).getQuantity());
1874 // Set the llvm linkage type as appropriate.
1875 llvm::GlobalValue::LinkageTypes Linkage =
1876 GetLLVMLinkageVarDefinition(D, GV->isConstant());
1877 GV->setLinkage(Linkage);
1879 // If required by the ABI, give definitions of static data members with inline
1880 // initializers linkonce_odr linkage.
1881 if (getCXXABI().isInlineInitializedStaticDataMemberLinkOnce() &&
1882 D->isStaticDataMember() && InitExpr &&
1883 !InitDecl->isThisDeclarationADefinition())
1884 GV->setLinkage(llvm::GlobalVariable::LinkOnceODRLinkage);
1886 if (Linkage == llvm::GlobalVariable::CommonLinkage)
1887 // common vars aren't constant even if declared const.
1888 GV->setConstant(false);
1890 SetCommonAttributes(D, GV);
1892 // Emit the initializer function if necessary.
1893 if (NeedsGlobalCtor || NeedsGlobalDtor)
1894 EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor);
1896 // If we are compiling with ASan, add metadata indicating dynamically
1897 // initialized globals.
1898 if (SanOpts.Address && NeedsGlobalCtor) {
1899 llvm::Module &M = getModule();
1901 llvm::NamedMDNode *DynamicInitializers =
1902 M.getOrInsertNamedMetadata("llvm.asan.dynamically_initialized_globals");
1903 llvm::Value *GlobalToAdd[] = { GV };
1904 llvm::MDNode *ThisGlobal = llvm::MDNode::get(VMContext, GlobalToAdd);
1905 DynamicInitializers->addOperand(ThisGlobal);
1908 // Emit global variable debug information.
1909 if (CGDebugInfo *DI = getModuleDebugInfo())
1910 if (getCodeGenOpts().getDebugInfo() >= CodeGenOptions::LimitedDebugInfo)
1911 DI->EmitGlobalVariable(GV, D);
1914 llvm::GlobalValue::LinkageTypes
1915 CodeGenModule::GetLLVMLinkageVarDefinition(const VarDecl *D, bool isConstant) {
1916 GVALinkage Linkage = getContext().GetGVALinkageForVariable(D);
1917 if (Linkage == GVA_Internal)
1918 return llvm::Function::InternalLinkage;
1919 else if (D->hasAttr<DLLImportAttr>())
1920 return llvm::Function::DLLImportLinkage;
1921 else if (D->hasAttr<DLLExportAttr>())
1922 return llvm::Function::DLLExportLinkage;
1923 else if (D->hasAttr<SelectAnyAttr>()) {
1924 // selectany symbols are externally visible, so use weak instead of
1925 // linkonce. MSVC optimizes away references to const selectany globals, so
1926 // all definitions should be the same and ODR linkage should be used.
1927 // http://msdn.microsoft.com/en-us/library/5tkz6s71.aspx
1928 return llvm::GlobalVariable::WeakODRLinkage;
1929 } else if (D->hasAttr<WeakAttr>()) {
1931 return llvm::GlobalVariable::WeakODRLinkage;
1933 return llvm::GlobalVariable::WeakAnyLinkage;
1934 } else if (Linkage == GVA_TemplateInstantiation ||
1935 Linkage == GVA_ExplicitTemplateInstantiation)
1936 return llvm::GlobalVariable::WeakODRLinkage;
1937 else if (!getLangOpts().CPlusPlus &&
1938 ((!CodeGenOpts.NoCommon && !D->getAttr<NoCommonAttr>()) ||
1939 D->getAttr<CommonAttr>()) &&
1940 !D->hasExternalStorage() && !D->getInit() &&
1941 !D->getAttr<SectionAttr>() && !D->getTLSKind() &&
1942 !D->getAttr<WeakImportAttr>()) {
1943 // Thread local vars aren't considered common linkage.
1944 return llvm::GlobalVariable::CommonLinkage;
1945 } else if (D->getTLSKind() == VarDecl::TLS_Dynamic &&
1946 getTarget().getTriple().isMacOSX())
1947 // On Darwin, the backing variable for a C++11 thread_local variable always
1948 // has internal linkage; all accesses should just be calls to the
1949 // Itanium-specified entry point, which has the normal linkage of the
1951 return llvm::GlobalValue::InternalLinkage;
1952 return llvm::GlobalVariable::ExternalLinkage;
1955 /// Replace the uses of a function that was declared with a non-proto type.
1956 /// We want to silently drop extra arguments from call sites
1957 static void replaceUsesOfNonProtoConstant(llvm::Constant *old,
1958 llvm::Function *newFn) {
1960 if (old->use_empty()) return;
1962 llvm::Type *newRetTy = newFn->getReturnType();
1963 SmallVector<llvm::Value*, 4> newArgs;
1965 for (llvm::Value::use_iterator ui = old->use_begin(), ue = old->use_end();
1967 llvm::Value::use_iterator use = ui++; // Increment before the use is erased.
1968 llvm::User *user = *use;
1970 // Recognize and replace uses of bitcasts. Most calls to
1971 // unprototyped functions will use bitcasts.
1972 if (llvm::ConstantExpr *bitcast = dyn_cast<llvm::ConstantExpr>(user)) {
1973 if (bitcast->getOpcode() == llvm::Instruction::BitCast)
1974 replaceUsesOfNonProtoConstant(bitcast, newFn);
1978 // Recognize calls to the function.
1979 llvm::CallSite callSite(user);
1980 if (!callSite) continue;
1981 if (!callSite.isCallee(use)) continue;
1983 // If the return types don't match exactly, then we can't
1984 // transform this call unless it's dead.
1985 if (callSite->getType() != newRetTy && !callSite->use_empty())
1988 // Get the call site's attribute list.
1989 SmallVector<llvm::AttributeSet, 8> newAttrs;
1990 llvm::AttributeSet oldAttrs = callSite.getAttributes();
1992 // Collect any return attributes from the call.
1993 if (oldAttrs.hasAttributes(llvm::AttributeSet::ReturnIndex))
1995 llvm::AttributeSet::get(newFn->getContext(),
1996 oldAttrs.getRetAttributes()));
1998 // If the function was passed too few arguments, don't transform.
1999 unsigned newNumArgs = newFn->arg_size();
2000 if (callSite.arg_size() < newNumArgs) continue;
2002 // If extra arguments were passed, we silently drop them.
2003 // If any of the types mismatch, we don't transform.
2005 bool dontTransform = false;
2006 for (llvm::Function::arg_iterator ai = newFn->arg_begin(),
2007 ae = newFn->arg_end(); ai != ae; ++ai, ++argNo) {
2008 if (callSite.getArgument(argNo)->getType() != ai->getType()) {
2009 dontTransform = true;
2013 // Add any parameter attributes.
2014 if (oldAttrs.hasAttributes(argNo + 1))
2017 AttributeSet::get(newFn->getContext(),
2018 oldAttrs.getParamAttributes(argNo + 1)));
2023 if (oldAttrs.hasAttributes(llvm::AttributeSet::FunctionIndex))
2024 newAttrs.push_back(llvm::AttributeSet::get(newFn->getContext(),
2025 oldAttrs.getFnAttributes()));
2027 // Okay, we can transform this. Create the new call instruction and copy
2028 // over the required information.
2029 newArgs.append(callSite.arg_begin(), callSite.arg_begin() + argNo);
2031 llvm::CallSite newCall;
2032 if (callSite.isCall()) {
2033 newCall = llvm::CallInst::Create(newFn, newArgs, "",
2034 callSite.getInstruction());
2036 llvm::InvokeInst *oldInvoke =
2037 cast<llvm::InvokeInst>(callSite.getInstruction());
2038 newCall = llvm::InvokeInst::Create(newFn,
2039 oldInvoke->getNormalDest(),
2040 oldInvoke->getUnwindDest(),
2042 callSite.getInstruction());
2044 newArgs.clear(); // for the next iteration
2046 if (!newCall->getType()->isVoidTy())
2047 newCall->takeName(callSite.getInstruction());
2048 newCall.setAttributes(
2049 llvm::AttributeSet::get(newFn->getContext(), newAttrs));
2050 newCall.setCallingConv(callSite.getCallingConv());
2052 // Finally, remove the old call, replacing any uses with the new one.
2053 if (!callSite->use_empty())
2054 callSite->replaceAllUsesWith(newCall.getInstruction());
2056 // Copy debug location attached to CI.
2057 if (!callSite->getDebugLoc().isUnknown())
2058 newCall->setDebugLoc(callSite->getDebugLoc());
2059 callSite->eraseFromParent();
2063 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we
2064 /// implement a function with no prototype, e.g. "int foo() {}". If there are
2065 /// existing call uses of the old function in the module, this adjusts them to
2066 /// call the new function directly.
2068 /// This is not just a cleanup: the always_inline pass requires direct calls to
2069 /// functions to be able to inline them. If there is a bitcast in the way, it
2070 /// won't inline them. Instcombine normally deletes these calls, but it isn't
2072 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old,
2073 llvm::Function *NewFn) {
2074 // If we're redefining a global as a function, don't transform it.
2075 if (!isa<llvm::Function>(Old)) return;
2077 replaceUsesOfNonProtoConstant(Old, NewFn);
2080 void CodeGenModule::HandleCXXStaticMemberVarInstantiation(VarDecl *VD) {
2081 TemplateSpecializationKind TSK = VD->getTemplateSpecializationKind();
2082 // If we have a definition, this might be a deferred decl. If the
2083 // instantiation is explicit, make sure we emit it at the end.
2084 if (VD->getDefinition() && TSK == TSK_ExplicitInstantiationDefinition)
2085 GetAddrOfGlobalVar(VD);
2087 EmitTopLevelDecl(VD);
2090 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD) {
2091 const FunctionDecl *D = cast<FunctionDecl>(GD.getDecl());
2093 // Compute the function info and LLVM type.
2094 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
2095 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
2097 // Get or create the prototype for the function.
2098 llvm::Constant *Entry = GetAddrOfFunction(GD, Ty);
2100 // Strip off a bitcast if we got one back.
2101 if (llvm::ConstantExpr *CE = dyn_cast<llvm::ConstantExpr>(Entry)) {
2102 assert(CE->getOpcode() == llvm::Instruction::BitCast);
2103 Entry = CE->getOperand(0);
2106 if (!cast<llvm::GlobalValue>(Entry)->isDeclaration()) {
2107 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name);
2111 if (cast<llvm::GlobalValue>(Entry)->getType()->getElementType() != Ty) {
2112 llvm::GlobalValue *OldFn = cast<llvm::GlobalValue>(Entry);
2114 // If the types mismatch then we have to rewrite the definition.
2115 assert(OldFn->isDeclaration() &&
2116 "Shouldn't replace non-declaration");
2118 // F is the Function* for the one with the wrong type, we must make a new
2119 // Function* and update everything that used F (a declaration) with the new
2120 // Function* (which will be a definition).
2122 // This happens if there is a prototype for a function
2123 // (e.g. "int f()") and then a definition of a different type
2124 // (e.g. "int f(int x)"). Move the old function aside so that it
2125 // doesn't interfere with GetAddrOfFunction.
2126 OldFn->setName(StringRef());
2127 llvm::Function *NewFn = cast<llvm::Function>(GetAddrOfFunction(GD, Ty));
2129 // This might be an implementation of a function without a
2130 // prototype, in which case, try to do special replacement of
2131 // calls which match the new prototype. The really key thing here
2132 // is that we also potentially drop arguments from the call site
2133 // so as to make a direct call, which makes the inliner happier
2134 // and suppresses a number of optimizer warnings (!) about
2135 // dropping arguments.
2136 if (!OldFn->use_empty()) {
2137 ReplaceUsesOfNonProtoTypeWithRealFunction(OldFn, NewFn);
2138 OldFn->removeDeadConstantUsers();
2141 // Replace uses of F with the Function we will endow with a body.
2142 if (!Entry->use_empty()) {
2143 llvm::Constant *NewPtrForOldDecl =
2144 llvm::ConstantExpr::getBitCast(NewFn, Entry->getType());
2145 Entry->replaceAllUsesWith(NewPtrForOldDecl);
2148 // Ok, delete the old function now, which is dead.
2149 OldFn->eraseFromParent();
2154 // We need to set linkage and visibility on the function before
2155 // generating code for it because various parts of IR generation
2156 // want to propagate this information down (e.g. to local static
2158 llvm::Function *Fn = cast<llvm::Function>(Entry);
2159 setFunctionLinkage(GD, Fn);
2161 // FIXME: this is redundant with part of SetFunctionDefinitionAttributes
2162 setGlobalVisibility(Fn, D);
2164 MaybeHandleStaticInExternC(D, Fn);
2166 CodeGenFunction(*this).GenerateCode(D, Fn, FI);
2168 SetFunctionDefinitionAttributes(D, Fn);
2169 SetLLVMFunctionAttributesForDefinition(D, Fn);
2171 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>())
2172 AddGlobalCtor(Fn, CA->getPriority());
2173 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>())
2174 AddGlobalDtor(Fn, DA->getPriority());
2175 if (D->hasAttr<AnnotateAttr>())
2176 AddGlobalAnnotations(D, Fn);
2179 void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) {
2180 const ValueDecl *D = cast<ValueDecl>(GD.getDecl());
2181 const AliasAttr *AA = D->getAttr<AliasAttr>();
2182 assert(AA && "Not an alias?");
2184 StringRef MangledName = getMangledName(GD);
2186 // If there is a definition in the module, then it wins over the alias.
2187 // This is dubious, but allow it to be safe. Just ignore the alias.
2188 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
2189 if (Entry && !Entry->isDeclaration())
2192 Aliases.push_back(GD);
2194 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType());
2196 // Create a reference to the named value. This ensures that it is emitted
2197 // if a deferred decl.
2198 llvm::Constant *Aliasee;
2199 if (isa<llvm::FunctionType>(DeclTy))
2200 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GD,
2201 /*ForVTable=*/false);
2203 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(),
2204 llvm::PointerType::getUnqual(DeclTy), 0);
2206 // Create the new alias itself, but don't set a name yet.
2207 llvm::GlobalValue *GA =
2208 new llvm::GlobalAlias(Aliasee->getType(),
2209 llvm::Function::ExternalLinkage,
2210 "", Aliasee, &getModule());
2213 assert(Entry->isDeclaration());
2215 // If there is a declaration in the module, then we had an extern followed
2216 // by the alias, as in:
2217 // extern int test6();
2219 // int test6() __attribute__((alias("test7")));
2221 // Remove it and replace uses of it with the alias.
2222 GA->takeName(Entry);
2224 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA,
2226 Entry->eraseFromParent();
2228 GA->setName(MangledName);
2231 // Set attributes which are particular to an alias; this is a
2232 // specialization of the attributes which may be set on a global
2233 // variable/function.
2234 if (D->hasAttr<DLLExportAttr>()) {
2235 if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
2236 // The dllexport attribute is ignored for undefined symbols.
2238 GA->setLinkage(llvm::Function::DLLExportLinkage);
2240 GA->setLinkage(llvm::Function::DLLExportLinkage);
2242 } else if (D->hasAttr<WeakAttr>() ||
2243 D->hasAttr<WeakRefAttr>() ||
2244 D->isWeakImported()) {
2245 GA->setLinkage(llvm::Function::WeakAnyLinkage);
2248 SetCommonAttributes(D, GA);
2251 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID,
2252 ArrayRef<llvm::Type*> Tys) {
2253 return llvm::Intrinsic::getDeclaration(&getModule(), (llvm::Intrinsic::ID)IID,
2257 static llvm::StringMapEntry<llvm::Constant*> &
2258 GetConstantCFStringEntry(llvm::StringMap<llvm::Constant*> &Map,
2259 const StringLiteral *Literal,
2262 unsigned &StringLength) {
2263 StringRef String = Literal->getString();
2264 unsigned NumBytes = String.size();
2266 // Check for simple case.
2267 if (!Literal->containsNonAsciiOrNull()) {
2268 StringLength = NumBytes;
2269 return Map.GetOrCreateValue(String);
2272 // Otherwise, convert the UTF8 literals into a string of shorts.
2275 SmallVector<UTF16, 128> ToBuf(NumBytes + 1); // +1 for ending nulls.
2276 const UTF8 *FromPtr = (const UTF8 *)String.data();
2277 UTF16 *ToPtr = &ToBuf[0];
2279 (void)ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes,
2280 &ToPtr, ToPtr + NumBytes,
2283 // ConvertUTF8toUTF16 returns the length in ToPtr.
2284 StringLength = ToPtr - &ToBuf[0];
2286 // Add an explicit null.
2289 GetOrCreateValue(StringRef(reinterpret_cast<const char *>(ToBuf.data()),
2290 (StringLength + 1) * 2));
2293 static llvm::StringMapEntry<llvm::Constant*> &
2294 GetConstantStringEntry(llvm::StringMap<llvm::Constant*> &Map,
2295 const StringLiteral *Literal,
2296 unsigned &StringLength) {
2297 StringRef String = Literal->getString();
2298 StringLength = String.size();
2299 return Map.GetOrCreateValue(String);
2303 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) {
2304 unsigned StringLength = 0;
2305 bool isUTF16 = false;
2306 llvm::StringMapEntry<llvm::Constant*> &Entry =
2307 GetConstantCFStringEntry(CFConstantStringMap, Literal,
2308 getDataLayout().isLittleEndian(),
2309 isUTF16, StringLength);
2311 if (llvm::Constant *C = Entry.getValue())
2314 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty);
2315 llvm::Constant *Zeros[] = { Zero, Zero };
2318 // If we don't already have it, get __CFConstantStringClassReference.
2319 if (!CFConstantStringClassRef) {
2320 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy);
2321 Ty = llvm::ArrayType::get(Ty, 0);
2322 llvm::Constant *GV = CreateRuntimeVariable(Ty,
2323 "__CFConstantStringClassReference");
2324 // Decay array -> ptr
2325 V = llvm::ConstantExpr::getGetElementPtr(GV, Zeros);
2326 CFConstantStringClassRef = V;
2329 V = CFConstantStringClassRef;
2331 QualType CFTy = getContext().getCFConstantStringType();
2333 llvm::StructType *STy =
2334 cast<llvm::StructType>(getTypes().ConvertType(CFTy));
2336 llvm::Constant *Fields[4];
2339 Fields[0] = cast<llvm::ConstantExpr>(V);
2342 llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy);
2343 Fields[1] = isUTF16 ? llvm::ConstantInt::get(Ty, 0x07d0) :
2344 llvm::ConstantInt::get(Ty, 0x07C8);
2347 llvm::Constant *C = 0;
2349 ArrayRef<uint16_t> Arr =
2350 llvm::makeArrayRef<uint16_t>(reinterpret_cast<uint16_t*>(
2351 const_cast<char *>(Entry.getKey().data())),
2352 Entry.getKey().size() / 2);
2353 C = llvm::ConstantDataArray::get(VMContext, Arr);
2355 C = llvm::ConstantDataArray::getString(VMContext, Entry.getKey());
2358 llvm::GlobalValue::LinkageTypes Linkage;
2360 // FIXME: why do utf strings get "_" labels instead of "L" labels?
2361 Linkage = llvm::GlobalValue::InternalLinkage;
2363 // FIXME: With OS X ld 123.2 (xcode 4) and LTO we would get a linker error
2364 // when using private linkage. It is not clear if this is a bug in ld
2365 // or a reasonable new restriction.
2366 Linkage = llvm::GlobalValue::LinkerPrivateLinkage;
2368 // Note: -fwritable-strings doesn't make the backing store strings of
2369 // CFStrings writable. (See <rdar://problem/10657500>)
2370 llvm::GlobalVariable *GV =
2371 new llvm::GlobalVariable(getModule(), C->getType(), /*isConstant=*/true,
2372 Linkage, C, ".str");
2373 GV->setUnnamedAddr(true);
2374 // Don't enforce the target's minimum global alignment, since the only use
2375 // of the string is via this class initializer.
2377 CharUnits Align = getContext().getTypeAlignInChars(getContext().ShortTy);
2378 GV->setAlignment(Align.getQuantity());
2380 CharUnits Align = getContext().getTypeAlignInChars(getContext().CharTy);
2381 GV->setAlignment(Align.getQuantity());
2385 Fields[2] = llvm::ConstantExpr::getGetElementPtr(GV, Zeros);
2388 // Cast the UTF16 string to the correct type.
2389 Fields[2] = llvm::ConstantExpr::getBitCast(Fields[2], Int8PtrTy);
2392 Ty = getTypes().ConvertType(getContext().LongTy);
2393 Fields[3] = llvm::ConstantInt::get(Ty, StringLength);
2396 C = llvm::ConstantStruct::get(STy, Fields);
2397 GV = new llvm::GlobalVariable(getModule(), C->getType(), true,
2398 llvm::GlobalVariable::PrivateLinkage, C,
2399 "_unnamed_cfstring_");
2400 if (const char *Sect = getTarget().getCFStringSection())
2401 GV->setSection(Sect);
2408 CreateRecordDecl(const ASTContext &Ctx, RecordDecl::TagKind TK,
2409 DeclContext *DC, IdentifierInfo *Id) {
2411 if (Ctx.getLangOpts().CPlusPlus)
2412 return CXXRecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
2414 return RecordDecl::Create(Ctx, TK, DC, Loc, Loc, Id);
2418 CodeGenModule::GetAddrOfConstantString(const StringLiteral *Literal) {
2419 unsigned StringLength = 0;
2420 llvm::StringMapEntry<llvm::Constant*> &Entry =
2421 GetConstantStringEntry(CFConstantStringMap, Literal, StringLength);
2423 if (llvm::Constant *C = Entry.getValue())
2426 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty);
2427 llvm::Constant *Zeros[] = { Zero, Zero };
2429 // If we don't already have it, get _NSConstantStringClassReference.
2430 if (!ConstantStringClassRef) {
2431 std::string StringClass(getLangOpts().ObjCConstantStringClass);
2432 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy);
2434 if (LangOpts.ObjCRuntime.isNonFragile()) {
2436 StringClass.empty() ? "OBJC_CLASS_$_NSConstantString"
2437 : "OBJC_CLASS_$_" + StringClass;
2438 GV = getObjCRuntime().GetClassGlobal(str);
2439 // Make sure the result is of the correct type.
2440 llvm::Type *PTy = llvm::PointerType::getUnqual(Ty);
2441 V = llvm::ConstantExpr::getBitCast(GV, PTy);
2442 ConstantStringClassRef = V;
2445 StringClass.empty() ? "_NSConstantStringClassReference"
2446 : "_" + StringClass + "ClassReference";
2447 llvm::Type *PTy = llvm::ArrayType::get(Ty, 0);
2448 GV = CreateRuntimeVariable(PTy, str);
2449 // Decay array -> ptr
2450 V = llvm::ConstantExpr::getGetElementPtr(GV, Zeros);
2451 ConstantStringClassRef = V;
2455 V = ConstantStringClassRef;
2457 if (!NSConstantStringType) {
2458 // Construct the type for a constant NSString.
2459 RecordDecl *D = CreateRecordDecl(Context, TTK_Struct,
2460 Context.getTranslationUnitDecl(),
2461 &Context.Idents.get("__builtin_NSString"));
2462 D->startDefinition();
2464 QualType FieldTypes[3];
2467 FieldTypes[0] = Context.getPointerType(Context.IntTy.withConst());
2469 FieldTypes[1] = Context.getPointerType(Context.CharTy.withConst());
2470 // unsigned int length;
2471 FieldTypes[2] = Context.UnsignedIntTy;
2474 for (unsigned i = 0; i < 3; ++i) {
2475 FieldDecl *Field = FieldDecl::Create(Context, D,
2477 SourceLocation(), 0,
2478 FieldTypes[i], /*TInfo=*/0,
2482 Field->setAccess(AS_public);
2486 D->completeDefinition();
2487 QualType NSTy = Context.getTagDeclType(D);
2488 NSConstantStringType = cast<llvm::StructType>(getTypes().ConvertType(NSTy));
2491 llvm::Constant *Fields[3];
2494 Fields[0] = cast<llvm::ConstantExpr>(V);
2498 llvm::ConstantDataArray::getString(VMContext, Entry.getKey());
2500 llvm::GlobalValue::LinkageTypes Linkage;
2502 Linkage = llvm::GlobalValue::PrivateLinkage;
2503 isConstant = !LangOpts.WritableStrings;
2505 llvm::GlobalVariable *GV =
2506 new llvm::GlobalVariable(getModule(), C->getType(), isConstant, Linkage, C,
2508 GV->setUnnamedAddr(true);
2509 // Don't enforce the target's minimum global alignment, since the only use
2510 // of the string is via this class initializer.
2511 CharUnits Align = getContext().getTypeAlignInChars(getContext().CharTy);
2512 GV->setAlignment(Align.getQuantity());
2513 Fields[1] = llvm::ConstantExpr::getGetElementPtr(GV, Zeros);
2516 llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy);
2517 Fields[2] = llvm::ConstantInt::get(Ty, StringLength);
2520 C = llvm::ConstantStruct::get(NSConstantStringType, Fields);
2521 GV = new llvm::GlobalVariable(getModule(), C->getType(), true,
2522 llvm::GlobalVariable::PrivateLinkage, C,
2523 "_unnamed_nsstring_");
2524 // FIXME. Fix section.
2525 if (const char *Sect =
2526 LangOpts.ObjCRuntime.isNonFragile()
2527 ? getTarget().getNSStringNonFragileABISection()
2528 : getTarget().getNSStringSection())
2529 GV->setSection(Sect);
2535 QualType CodeGenModule::getObjCFastEnumerationStateType() {
2536 if (ObjCFastEnumerationStateType.isNull()) {
2537 RecordDecl *D = CreateRecordDecl(Context, TTK_Struct,
2538 Context.getTranslationUnitDecl(),
2539 &Context.Idents.get("__objcFastEnumerationState"));
2540 D->startDefinition();
2542 QualType FieldTypes[] = {
2543 Context.UnsignedLongTy,
2544 Context.getPointerType(Context.getObjCIdType()),
2545 Context.getPointerType(Context.UnsignedLongTy),
2546 Context.getConstantArrayType(Context.UnsignedLongTy,
2547 llvm::APInt(32, 5), ArrayType::Normal, 0)
2550 for (size_t i = 0; i < 4; ++i) {
2551 FieldDecl *Field = FieldDecl::Create(Context,
2554 SourceLocation(), 0,
2555 FieldTypes[i], /*TInfo=*/0,
2559 Field->setAccess(AS_public);
2563 D->completeDefinition();
2564 ObjCFastEnumerationStateType = Context.getTagDeclType(D);
2567 return ObjCFastEnumerationStateType;
2571 CodeGenModule::GetConstantArrayFromStringLiteral(const StringLiteral *E) {
2572 assert(!E->getType()->isPointerType() && "Strings are always arrays");
2574 // Don't emit it as the address of the string, emit the string data itself
2575 // as an inline array.
2576 if (E->getCharByteWidth() == 1) {
2577 SmallString<64> Str(E->getString());
2579 // Resize the string to the right size, which is indicated by its type.
2580 const ConstantArrayType *CAT = Context.getAsConstantArrayType(E->getType());
2581 Str.resize(CAT->getSize().getZExtValue());
2582 return llvm::ConstantDataArray::getString(VMContext, Str, false);
2585 llvm::ArrayType *AType =
2586 cast<llvm::ArrayType>(getTypes().ConvertType(E->getType()));
2587 llvm::Type *ElemTy = AType->getElementType();
2588 unsigned NumElements = AType->getNumElements();
2590 // Wide strings have either 2-byte or 4-byte elements.
2591 if (ElemTy->getPrimitiveSizeInBits() == 16) {
2592 SmallVector<uint16_t, 32> Elements;
2593 Elements.reserve(NumElements);
2595 for(unsigned i = 0, e = E->getLength(); i != e; ++i)
2596 Elements.push_back(E->getCodeUnit(i));
2597 Elements.resize(NumElements);
2598 return llvm::ConstantDataArray::get(VMContext, Elements);
2601 assert(ElemTy->getPrimitiveSizeInBits() == 32);
2602 SmallVector<uint32_t, 32> Elements;
2603 Elements.reserve(NumElements);
2605 for(unsigned i = 0, e = E->getLength(); i != e; ++i)
2606 Elements.push_back(E->getCodeUnit(i));
2607 Elements.resize(NumElements);
2608 return llvm::ConstantDataArray::get(VMContext, Elements);
2611 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a
2612 /// constant array for the given string literal.
2614 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S) {
2615 CharUnits Align = getContext().getAlignOfGlobalVarInChars(S->getType());
2616 if (S->isAscii() || S->isUTF8()) {
2617 SmallString<64> Str(S->getString());
2619 // Resize the string to the right size, which is indicated by its type.
2620 const ConstantArrayType *CAT = Context.getAsConstantArrayType(S->getType());
2621 Str.resize(CAT->getSize().getZExtValue());
2622 return GetAddrOfConstantString(Str, /*GlobalName*/ 0, Align.getQuantity());
2625 // FIXME: the following does not memoize wide strings.
2626 llvm::Constant *C = GetConstantArrayFromStringLiteral(S);
2627 llvm::GlobalVariable *GV =
2628 new llvm::GlobalVariable(getModule(),C->getType(),
2629 !LangOpts.WritableStrings,
2630 llvm::GlobalValue::PrivateLinkage,
2633 GV->setAlignment(Align.getQuantity());
2634 GV->setUnnamedAddr(true);
2638 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant
2639 /// array for the given ObjCEncodeExpr node.
2641 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) {
2643 getContext().getObjCEncodingForType(E->getEncodedType(), Str);
2645 return GetAddrOfConstantCString(Str);
2649 /// GenerateWritableString -- Creates storage for a string literal.
2650 static llvm::GlobalVariable *GenerateStringLiteral(StringRef str,
2653 const char *GlobalName,
2654 unsigned Alignment) {
2655 // Create Constant for this string literal. Don't add a '\0'.
2657 llvm::ConstantDataArray::getString(CGM.getLLVMContext(), str, false);
2659 // OpenCL v1.1 s6.5.3: a string literal is in the constant address space.
2660 unsigned AddrSpace = 0;
2661 if (CGM.getLangOpts().OpenCL)
2662 AddrSpace = CGM.getContext().getTargetAddressSpace(LangAS::opencl_constant);
2664 // Create a global variable for this string
2665 llvm::GlobalVariable *GV = new llvm::GlobalVariable(
2666 CGM.getModule(), C->getType(), constant,
2667 llvm::GlobalValue::PrivateLinkage, C, GlobalName, 0,
2668 llvm::GlobalVariable::NotThreadLocal, AddrSpace);
2669 GV->setAlignment(Alignment);
2670 GV->setUnnamedAddr(true);
2674 /// GetAddrOfConstantString - Returns a pointer to a character array
2675 /// containing the literal. This contents are exactly that of the
2676 /// given string, i.e. it will not be null terminated automatically;
2677 /// see GetAddrOfConstantCString. Note that whether the result is
2678 /// actually a pointer to an LLVM constant depends on
2679 /// Feature.WriteableStrings.
2681 /// The result has pointer to array type.
2682 llvm::Constant *CodeGenModule::GetAddrOfConstantString(StringRef Str,
2683 const char *GlobalName,
2684 unsigned Alignment) {
2685 // Get the default prefix if a name wasn't specified.
2687 GlobalName = ".str";
2690 Alignment = getContext().getAlignOfGlobalVarInChars(getContext().CharTy)
2693 // Don't share any string literals if strings aren't constant.
2694 if (LangOpts.WritableStrings)
2695 return GenerateStringLiteral(Str, false, *this, GlobalName, Alignment);
2697 llvm::StringMapEntry<llvm::GlobalVariable *> &Entry =
2698 ConstantStringMap.GetOrCreateValue(Str);
2700 if (llvm::GlobalVariable *GV = Entry.getValue()) {
2701 if (Alignment > GV->getAlignment()) {
2702 GV->setAlignment(Alignment);
2707 // Create a global variable for this.
2708 llvm::GlobalVariable *GV = GenerateStringLiteral(Str, true, *this, GlobalName,
2714 /// GetAddrOfConstantCString - Returns a pointer to a character
2715 /// array containing the literal and a terminating '\0'
2716 /// character. The result has pointer to array type.
2717 llvm::Constant *CodeGenModule::GetAddrOfConstantCString(const std::string &Str,
2718 const char *GlobalName,
2719 unsigned Alignment) {
2720 StringRef StrWithNull(Str.c_str(), Str.size() + 1);
2721 return GetAddrOfConstantString(StrWithNull, GlobalName, Alignment);
2724 llvm::Constant *CodeGenModule::GetAddrOfGlobalTemporary(
2725 const MaterializeTemporaryExpr *E, const Expr *Init) {
2726 assert((E->getStorageDuration() == SD_Static ||
2727 E->getStorageDuration() == SD_Thread) && "not a global temporary");
2728 const VarDecl *VD = cast<VarDecl>(E->getExtendingDecl());
2730 // If we're not materializing a subobject of the temporary, keep the
2731 // cv-qualifiers from the type of the MaterializeTemporaryExpr.
2732 QualType MaterializedType = Init->getType();
2733 if (Init == E->GetTemporaryExpr())
2734 MaterializedType = E->getType();
2736 llvm::Constant *&Slot = MaterializedGlobalTemporaryMap[E];
2740 // FIXME: If an externally-visible declaration extends multiple temporaries,
2741 // we need to give each temporary the same name in every translation unit (and
2742 // we also need to make the temporaries externally-visible).
2743 SmallString<256> Name;
2744 llvm::raw_svector_ostream Out(Name);
2745 getCXXABI().getMangleContext().mangleReferenceTemporary(VD, Out);
2749 if (E->getStorageDuration() == SD_Static) {
2750 // We might have a cached constant initializer for this temporary. Note
2751 // that this might have a different value from the value computed by
2752 // evaluating the initializer if the surrounding constant expression
2753 // modifies the temporary.
2754 Value = getContext().getMaterializedTemporaryValue(E, false);
2755 if (Value && Value->isUninit())
2759 // Try evaluating it now, it might have a constant initializer.
2760 Expr::EvalResult EvalResult;
2761 if (!Value && Init->EvaluateAsRValue(EvalResult, getContext()) &&
2762 !EvalResult.hasSideEffects())
2763 Value = &EvalResult.Val;
2765 llvm::Constant *InitialValue = 0;
2766 bool Constant = false;
2769 // The temporary has a constant initializer, use it.
2770 InitialValue = EmitConstantValue(*Value, MaterializedType, 0);
2771 Constant = isTypeConstant(MaterializedType, /*ExcludeCtor*/Value);
2772 Type = InitialValue->getType();
2774 // No initializer, the initialization will be provided when we
2775 // initialize the declaration which performed lifetime extension.
2776 Type = getTypes().ConvertTypeForMem(MaterializedType);
2779 // Create a global variable for this lifetime-extended temporary.
2780 llvm::GlobalVariable *GV =
2781 new llvm::GlobalVariable(getModule(), Type, Constant,
2782 llvm::GlobalValue::PrivateLinkage,
2783 InitialValue, Name.c_str());
2785 getContext().getTypeAlignInChars(MaterializedType).getQuantity());
2786 if (VD->getTLSKind())
2787 setTLSMode(GV, *VD);
2792 /// EmitObjCPropertyImplementations - Emit information for synthesized
2793 /// properties for an implementation.
2794 void CodeGenModule::EmitObjCPropertyImplementations(const
2795 ObjCImplementationDecl *D) {
2796 for (ObjCImplementationDecl::propimpl_iterator
2797 i = D->propimpl_begin(), e = D->propimpl_end(); i != e; ++i) {
2798 ObjCPropertyImplDecl *PID = *i;
2800 // Dynamic is just for type-checking.
2801 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) {
2802 ObjCPropertyDecl *PD = PID->getPropertyDecl();
2804 // Determine which methods need to be implemented, some may have
2805 // been overridden. Note that ::isPropertyAccessor is not the method
2806 // we want, that just indicates if the decl came from a
2807 // property. What we want to know is if the method is defined in
2808 // this implementation.
2809 if (!D->getInstanceMethod(PD->getGetterName()))
2810 CodeGenFunction(*this).GenerateObjCGetter(
2811 const_cast<ObjCImplementationDecl *>(D), PID);
2812 if (!PD->isReadOnly() &&
2813 !D->getInstanceMethod(PD->getSetterName()))
2814 CodeGenFunction(*this).GenerateObjCSetter(
2815 const_cast<ObjCImplementationDecl *>(D), PID);
2820 static bool needsDestructMethod(ObjCImplementationDecl *impl) {
2821 const ObjCInterfaceDecl *iface = impl->getClassInterface();
2822 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
2823 ivar; ivar = ivar->getNextIvar())
2824 if (ivar->getType().isDestructedType())
2830 /// EmitObjCIvarInitializations - Emit information for ivar initialization
2831 /// for an implementation.
2832 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) {
2833 // We might need a .cxx_destruct even if we don't have any ivar initializers.
2834 if (needsDestructMethod(D)) {
2835 IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct");
2836 Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
2837 ObjCMethodDecl *DTORMethod =
2838 ObjCMethodDecl::Create(getContext(), D->getLocation(), D->getLocation(),
2839 cxxSelector, getContext().VoidTy, 0, D,
2840 /*isInstance=*/true, /*isVariadic=*/false,
2841 /*isPropertyAccessor=*/true, /*isImplicitlyDeclared=*/true,
2842 /*isDefined=*/false, ObjCMethodDecl::Required);
2843 D->addInstanceMethod(DTORMethod);
2844 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false);
2845 D->setHasDestructors(true);
2848 // If the implementation doesn't have any ivar initializers, we don't need
2849 // a .cxx_construct.
2850 if (D->getNumIvarInitializers() == 0)
2853 IdentifierInfo *II = &getContext().Idents.get(".cxx_construct");
2854 Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
2855 // The constructor returns 'self'.
2856 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create(getContext(),
2860 getContext().getObjCIdType(), 0,
2861 D, /*isInstance=*/true,
2862 /*isVariadic=*/false,
2863 /*isPropertyAccessor=*/true,
2864 /*isImplicitlyDeclared=*/true,
2865 /*isDefined=*/false,
2866 ObjCMethodDecl::Required);
2867 D->addInstanceMethod(CTORMethod);
2868 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true);
2869 D->setHasNonZeroConstructors(true);
2872 /// EmitNamespace - Emit all declarations in a namespace.
2873 void CodeGenModule::EmitNamespace(const NamespaceDecl *ND) {
2874 for (RecordDecl::decl_iterator I = ND->decls_begin(), E = ND->decls_end();
2876 if (const VarDecl *VD = dyn_cast<VarDecl>(*I))
2877 if (VD->getTemplateSpecializationKind() != TSK_ExplicitSpecialization &&
2878 VD->getTemplateSpecializationKind() != TSK_Undeclared)
2880 EmitTopLevelDecl(*I);
2884 // EmitLinkageSpec - Emit all declarations in a linkage spec.
2885 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) {
2886 if (LSD->getLanguage() != LinkageSpecDecl::lang_c &&
2887 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) {
2888 ErrorUnsupported(LSD, "linkage spec");
2892 for (RecordDecl::decl_iterator I = LSD->decls_begin(), E = LSD->decls_end();
2894 // Meta-data for ObjC class includes references to implemented methods.
2895 // Generate class's method definitions first.
2896 if (ObjCImplDecl *OID = dyn_cast<ObjCImplDecl>(*I)) {
2897 for (ObjCContainerDecl::method_iterator M = OID->meth_begin(),
2898 MEnd = OID->meth_end();
2900 EmitTopLevelDecl(*M);
2902 EmitTopLevelDecl(*I);
2906 /// EmitTopLevelDecl - Emit code for a single top level declaration.
2907 void CodeGenModule::EmitTopLevelDecl(Decl *D) {
2908 // Ignore dependent declarations.
2909 if (D->getDeclContext() && D->getDeclContext()->isDependentContext())
2912 switch (D->getKind()) {
2913 case Decl::CXXConversion:
2914 case Decl::CXXMethod:
2915 case Decl::Function:
2916 // Skip function templates
2917 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() ||
2918 cast<FunctionDecl>(D)->isLateTemplateParsed())
2921 EmitGlobal(cast<FunctionDecl>(D));
2925 // Skip variable templates
2926 if (cast<VarDecl>(D)->getDescribedVarTemplate())
2928 case Decl::VarTemplateSpecialization:
2929 EmitGlobal(cast<VarDecl>(D));
2932 // Indirect fields from global anonymous structs and unions can be
2933 // ignored; only the actual variable requires IR gen support.
2934 case Decl::IndirectField:
2938 case Decl::Namespace:
2939 EmitNamespace(cast<NamespaceDecl>(D));
2941 // No code generation needed.
2942 case Decl::UsingShadow:
2944 case Decl::ClassTemplate:
2945 case Decl::VarTemplate:
2946 case Decl::VarTemplatePartialSpecialization:
2947 case Decl::FunctionTemplate:
2948 case Decl::TypeAliasTemplate:
2952 case Decl::NamespaceAlias:
2953 if (CGDebugInfo *DI = getModuleDebugInfo())
2954 DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(*D));
2956 case Decl::UsingDirective: // using namespace X; [C++]
2957 if (CGDebugInfo *DI = getModuleDebugInfo())
2958 DI->EmitUsingDirective(cast<UsingDirectiveDecl>(*D));
2960 case Decl::CXXConstructor:
2961 // Skip function templates
2962 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() ||
2963 cast<FunctionDecl>(D)->isLateTemplateParsed())
2966 getCXXABI().EmitCXXConstructors(cast<CXXConstructorDecl>(D));
2968 case Decl::CXXDestructor:
2969 if (cast<FunctionDecl>(D)->isLateTemplateParsed())
2971 getCXXABI().EmitCXXDestructors(cast<CXXDestructorDecl>(D));
2974 case Decl::StaticAssert:
2978 // Objective-C Decls
2980 // Forward declarations, no (immediate) code generation.
2981 case Decl::ObjCInterface:
2982 case Decl::ObjCCategory:
2985 case Decl::ObjCProtocol: {
2986 ObjCProtocolDecl *Proto = cast<ObjCProtocolDecl>(D);
2987 if (Proto->isThisDeclarationADefinition())
2988 ObjCRuntime->GenerateProtocol(Proto);
2992 case Decl::ObjCCategoryImpl:
2993 // Categories have properties but don't support synthesize so we
2994 // can ignore them here.
2995 ObjCRuntime->GenerateCategory(cast<ObjCCategoryImplDecl>(D));
2998 case Decl::ObjCImplementation: {
2999 ObjCImplementationDecl *OMD = cast<ObjCImplementationDecl>(D);
3000 EmitObjCPropertyImplementations(OMD);
3001 EmitObjCIvarInitializations(OMD);
3002 ObjCRuntime->GenerateClass(OMD);
3003 // Emit global variable debug information.
3004 if (CGDebugInfo *DI = getModuleDebugInfo())
3005 if (getCodeGenOpts().getDebugInfo() >= CodeGenOptions::LimitedDebugInfo)
3006 DI->getOrCreateInterfaceType(getContext().getObjCInterfaceType(
3007 OMD->getClassInterface()), OMD->getLocation());
3010 case Decl::ObjCMethod: {
3011 ObjCMethodDecl *OMD = cast<ObjCMethodDecl>(D);
3012 // If this is not a prototype, emit the body.
3014 CodeGenFunction(*this).GenerateObjCMethod(OMD);
3017 case Decl::ObjCCompatibleAlias:
3018 ObjCRuntime->RegisterAlias(cast<ObjCCompatibleAliasDecl>(D));
3021 case Decl::LinkageSpec:
3022 EmitLinkageSpec(cast<LinkageSpecDecl>(D));
3025 case Decl::FileScopeAsm: {
3026 FileScopeAsmDecl *AD = cast<FileScopeAsmDecl>(D);
3027 StringRef AsmString = AD->getAsmString()->getString();
3029 const std::string &S = getModule().getModuleInlineAsm();
3031 getModule().setModuleInlineAsm(AsmString);
3032 else if (S.end()[-1] == '\n')
3033 getModule().setModuleInlineAsm(S + AsmString.str());
3035 getModule().setModuleInlineAsm(S + '\n' + AsmString.str());
3039 case Decl::Import: {
3040 ImportDecl *Import = cast<ImportDecl>(D);
3042 // Ignore import declarations that come from imported modules.
3043 if (clang::Module *Owner = Import->getOwningModule()) {
3044 if (getLangOpts().CurrentModule.empty() ||
3045 Owner->getTopLevelModule()->Name == getLangOpts().CurrentModule)
3049 ImportedModules.insert(Import->getImportedModule());
3054 // Make sure we handled everything we should, every other kind is a
3055 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind
3056 // function. Need to recode Decl::Kind to do that easily.
3057 assert(isa<TypeDecl>(D) && "Unsupported decl kind");
3061 /// Turns the given pointer into a constant.
3062 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context,
3064 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr);
3065 llvm::Type *i64 = llvm::Type::getInt64Ty(Context);
3066 return llvm::ConstantInt::get(i64, PtrInt);
3069 static void EmitGlobalDeclMetadata(CodeGenModule &CGM,
3070 llvm::NamedMDNode *&GlobalMetadata,
3072 llvm::GlobalValue *Addr) {
3073 if (!GlobalMetadata)
3075 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs");
3077 // TODO: should we report variant information for ctors/dtors?
3078 llvm::Value *Ops[] = {
3080 GetPointerConstant(CGM.getLLVMContext(), D.getDecl())
3082 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
3085 /// For each function which is declared within an extern "C" region and marked
3086 /// as 'used', but has internal linkage, create an alias from the unmangled
3087 /// name to the mangled name if possible. People expect to be able to refer
3088 /// to such functions with an unmangled name from inline assembly within the
3089 /// same translation unit.
3090 void CodeGenModule::EmitStaticExternCAliases() {
3091 for (StaticExternCMap::iterator I = StaticExternCValues.begin(),
3092 E = StaticExternCValues.end();
3094 IdentifierInfo *Name = I->first;
3095 llvm::GlobalValue *Val = I->second;
3096 if (Val && !getModule().getNamedValue(Name->getName()))
3097 AddUsedGlobal(new llvm::GlobalAlias(Val->getType(), Val->getLinkage(),
3098 Name->getName(), Val, &getModule()));
3102 /// Emits metadata nodes associating all the global values in the
3103 /// current module with the Decls they came from. This is useful for
3104 /// projects using IR gen as a subroutine.
3106 /// Since there's currently no way to associate an MDNode directly
3107 /// with an llvm::GlobalValue, we create a global named metadata
3108 /// with the name 'clang.global.decl.ptrs'.
3109 void CodeGenModule::EmitDeclMetadata() {
3110 llvm::NamedMDNode *GlobalMetadata = 0;
3112 // StaticLocalDeclMap
3113 for (llvm::DenseMap<GlobalDecl,StringRef>::iterator
3114 I = MangledDeclNames.begin(), E = MangledDeclNames.end();
3116 llvm::GlobalValue *Addr = getModule().getNamedValue(I->second);
3117 EmitGlobalDeclMetadata(*this, GlobalMetadata, I->first, Addr);
3121 /// Emits metadata nodes for all the local variables in the current
3123 void CodeGenFunction::EmitDeclMetadata() {
3124 if (LocalDeclMap.empty()) return;
3126 llvm::LLVMContext &Context = getLLVMContext();
3128 // Find the unique metadata ID for this name.
3129 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr");
3131 llvm::NamedMDNode *GlobalMetadata = 0;
3133 for (llvm::DenseMap<const Decl*, llvm::Value*>::iterator
3134 I = LocalDeclMap.begin(), E = LocalDeclMap.end(); I != E; ++I) {
3135 const Decl *D = I->first;
3136 llvm::Value *Addr = I->second;
3138 if (llvm::AllocaInst *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) {
3139 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D);
3140 Alloca->setMetadata(DeclPtrKind, llvm::MDNode::get(Context, DAddr));
3141 } else if (llvm::GlobalValue *GV = dyn_cast<llvm::GlobalValue>(Addr)) {
3142 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D));
3143 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV);
3148 void CodeGenModule::EmitVersionIdentMetadata() {
3149 llvm::NamedMDNode *IdentMetadata =
3150 TheModule.getOrInsertNamedMetadata("llvm.ident");
3151 std::string Version = getClangFullVersion();
3152 llvm::LLVMContext &Ctx = TheModule.getContext();
3154 llvm::Value *IdentNode[] = {
3155 llvm::MDString::get(Ctx, Version)
3157 IdentMetadata->addOperand(llvm::MDNode::get(Ctx, IdentNode));
3160 void CodeGenModule::EmitCoverageFile() {
3161 if (!getCodeGenOpts().CoverageFile.empty()) {
3162 if (llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu")) {
3163 llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov");
3164 llvm::LLVMContext &Ctx = TheModule.getContext();
3165 llvm::MDString *CoverageFile =
3166 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageFile);
3167 for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) {
3168 llvm::MDNode *CU = CUNode->getOperand(i);
3169 llvm::Value *node[] = { CoverageFile, CU };
3170 llvm::MDNode *N = llvm::MDNode::get(Ctx, node);
3171 GCov->addOperand(N);
3177 llvm::Constant *CodeGenModule::EmitUuidofInitializer(StringRef Uuid,
3178 QualType GuidType) {
3179 // Sema has checked that all uuid strings are of the form
3180 // "12345678-1234-1234-1234-1234567890ab".
3181 assert(Uuid.size() == 36);
3182 for (unsigned i = 0; i < 36; ++i) {
3183 if (i == 8 || i == 13 || i == 18 || i == 23) assert(Uuid[i] == '-');
3184 else assert(isHexDigit(Uuid[i]));
3187 const unsigned Field3ValueOffsets[8] = { 19, 21, 24, 26, 28, 30, 32, 34 };
3189 llvm::Constant *Field3[8];
3190 for (unsigned Idx = 0; Idx < 8; ++Idx)
3191 Field3[Idx] = llvm::ConstantInt::get(
3192 Int8Ty, Uuid.substr(Field3ValueOffsets[Idx], 2), 16);
3194 llvm::Constant *Fields[4] = {
3195 llvm::ConstantInt::get(Int32Ty, Uuid.substr(0, 8), 16),
3196 llvm::ConstantInt::get(Int16Ty, Uuid.substr(9, 4), 16),
3197 llvm::ConstantInt::get(Int16Ty, Uuid.substr(14, 4), 16),
3198 llvm::ConstantArray::get(llvm::ArrayType::get(Int8Ty, 8), Field3)
3201 return llvm::ConstantStruct::getAnon(Fields);