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"
16 #include "CGCUDARuntime.h"
19 #include "CGDebugInfo.h"
20 #include "CGObjCRuntime.h"
21 #include "CGOpenCLRuntime.h"
22 #include "CGOpenMPRuntime.h"
23 #include "CodeGenFunction.h"
24 #include "CodeGenPGO.h"
25 #include "CodeGenTBAA.h"
26 #include "CoverageMappingGen.h"
27 #include "TargetInfo.h"
28 #include "clang/AST/ASTContext.h"
29 #include "clang/AST/CharUnits.h"
30 #include "clang/AST/DeclCXX.h"
31 #include "clang/AST/DeclObjC.h"
32 #include "clang/AST/DeclTemplate.h"
33 #include "clang/AST/Mangle.h"
34 #include "clang/AST/RecordLayout.h"
35 #include "clang/AST/RecursiveASTVisitor.h"
36 #include "clang/Basic/Builtins.h"
37 #include "clang/Basic/CharInfo.h"
38 #include "clang/Basic/Diagnostic.h"
39 #include "clang/Basic/Module.h"
40 #include "clang/Basic/SourceManager.h"
41 #include "clang/Basic/TargetInfo.h"
42 #include "clang/Basic/Version.h"
43 #include "clang/Frontend/CodeGenOptions.h"
44 #include "clang/Sema/SemaDiagnostic.h"
45 #include "llvm/ADT/APSInt.h"
46 #include "llvm/ADT/Triple.h"
47 #include "llvm/IR/CallSite.h"
48 #include "llvm/IR/CallingConv.h"
49 #include "llvm/IR/DataLayout.h"
50 #include "llvm/IR/Intrinsics.h"
51 #include "llvm/IR/LLVMContext.h"
52 #include "llvm/IR/Module.h"
53 #include "llvm/ProfileData/InstrProfReader.h"
54 #include "llvm/Support/ConvertUTF.h"
55 #include "llvm/Support/ErrorHandling.h"
56 #include "llvm/Support/MD5.h"
58 using namespace clang;
59 using namespace CodeGen;
61 static const char AnnotationSection[] = "llvm.metadata";
63 static CGCXXABI *createCXXABI(CodeGenModule &CGM) {
64 switch (CGM.getTarget().getCXXABI().getKind()) {
65 case TargetCXXABI::GenericAArch64:
66 case TargetCXXABI::GenericARM:
67 case TargetCXXABI::iOS:
68 case TargetCXXABI::iOS64:
69 case TargetCXXABI::WatchOS:
70 case TargetCXXABI::GenericMIPS:
71 case TargetCXXABI::GenericItanium:
72 case TargetCXXABI::WebAssembly:
73 return CreateItaniumCXXABI(CGM);
74 case TargetCXXABI::Microsoft:
75 return CreateMicrosoftCXXABI(CGM);
78 llvm_unreachable("invalid C++ ABI kind");
81 CodeGenModule::CodeGenModule(ASTContext &C, const HeaderSearchOptions &HSO,
82 const PreprocessorOptions &PPO,
83 const CodeGenOptions &CGO, llvm::Module &M,
84 DiagnosticsEngine &diags,
85 CoverageSourceInfo *CoverageInfo)
86 : Context(C), LangOpts(C.getLangOpts()), HeaderSearchOpts(HSO),
87 PreprocessorOpts(PPO), CodeGenOpts(CGO), TheModule(M), Diags(diags),
88 Target(C.getTargetInfo()), ABI(createCXXABI(*this)),
89 VMContext(M.getContext()), TBAA(nullptr), TheTargetCodeGenInfo(nullptr),
90 Types(*this), VTables(*this), ObjCRuntime(nullptr),
91 OpenCLRuntime(nullptr), OpenMPRuntime(nullptr), CUDARuntime(nullptr),
92 DebugInfo(nullptr), ObjCData(nullptr),
93 NoObjCARCExceptionsMetadata(nullptr), PGOReader(nullptr),
94 CFConstantStringClassRef(nullptr), ConstantStringClassRef(nullptr),
95 NSConstantStringType(nullptr), NSConcreteGlobalBlock(nullptr),
96 NSConcreteStackBlock(nullptr), BlockObjectAssign(nullptr),
97 BlockObjectDispose(nullptr), BlockDescriptorType(nullptr),
98 GenericBlockLiteralType(nullptr), LifetimeStartFn(nullptr),
99 LifetimeEndFn(nullptr), SanitizerMD(new SanitizerMetadata(*this)) {
101 // Initialize the type cache.
102 llvm::LLVMContext &LLVMContext = M.getContext();
103 VoidTy = llvm::Type::getVoidTy(LLVMContext);
104 Int8Ty = llvm::Type::getInt8Ty(LLVMContext);
105 Int16Ty = llvm::Type::getInt16Ty(LLVMContext);
106 Int32Ty = llvm::Type::getInt32Ty(LLVMContext);
107 Int64Ty = llvm::Type::getInt64Ty(LLVMContext);
108 FloatTy = llvm::Type::getFloatTy(LLVMContext);
109 DoubleTy = llvm::Type::getDoubleTy(LLVMContext);
110 PointerWidthInBits = C.getTargetInfo().getPointerWidth(0);
111 PointerAlignInBytes =
112 C.toCharUnitsFromBits(C.getTargetInfo().getPointerAlign(0)).getQuantity();
114 C.toCharUnitsFromBits(C.getTargetInfo().getIntAlign()).getQuantity();
115 IntTy = llvm::IntegerType::get(LLVMContext, C.getTargetInfo().getIntWidth());
116 IntPtrTy = llvm::IntegerType::get(LLVMContext, PointerWidthInBits);
117 Int8PtrTy = Int8Ty->getPointerTo(0);
118 Int8PtrPtrTy = Int8PtrTy->getPointerTo(0);
120 RuntimeCC = getTargetCodeGenInfo().getABIInfo().getRuntimeCC();
121 BuiltinCC = getTargetCodeGenInfo().getABIInfo().getBuiltinCC();
126 createOpenCLRuntime();
128 createOpenMPRuntime();
132 // Enable TBAA unless it's suppressed. ThreadSanitizer needs TBAA even at O0.
133 if (LangOpts.Sanitize.has(SanitizerKind::Thread) ||
134 (!CodeGenOpts.RelaxedAliasing && CodeGenOpts.OptimizationLevel > 0))
135 TBAA = new CodeGenTBAA(Context, VMContext, CodeGenOpts, getLangOpts(),
136 getCXXABI().getMangleContext());
138 // If debug info or coverage generation is enabled, create the CGDebugInfo
140 if (CodeGenOpts.getDebugInfo() != CodeGenOptions::NoDebugInfo ||
141 CodeGenOpts.EmitGcovArcs ||
142 CodeGenOpts.EmitGcovNotes)
143 DebugInfo = new CGDebugInfo(*this);
145 Block.GlobalUniqueCount = 0;
147 if (C.getLangOpts().ObjC1)
148 ObjCData = new ObjCEntrypoints();
150 if (!CodeGenOpts.InstrProfileInput.empty()) {
152 llvm::IndexedInstrProfReader::create(CodeGenOpts.InstrProfileInput);
153 if (std::error_code EC = ReaderOrErr.getError()) {
154 unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
155 "Could not read profile %0: %1");
156 getDiags().Report(DiagID) << CodeGenOpts.InstrProfileInput
159 PGOReader = std::move(ReaderOrErr.get());
162 // If coverage mapping generation is enabled, create the
163 // CoverageMappingModuleGen object.
164 if (CodeGenOpts.CoverageMapping)
165 CoverageMapping.reset(new CoverageMappingModuleGen(*this, *CoverageInfo));
168 CodeGenModule::~CodeGenModule() {
170 delete OpenCLRuntime;
171 delete OpenMPRuntime;
173 delete TheTargetCodeGenInfo;
179 void CodeGenModule::createObjCRuntime() {
180 // This is just isGNUFamily(), but we want to force implementors of
181 // new ABIs to decide how best to do this.
182 switch (LangOpts.ObjCRuntime.getKind()) {
183 case ObjCRuntime::GNUstep:
184 case ObjCRuntime::GCC:
185 case ObjCRuntime::ObjFW:
186 ObjCRuntime = CreateGNUObjCRuntime(*this);
189 case ObjCRuntime::FragileMacOSX:
190 case ObjCRuntime::MacOSX:
191 case ObjCRuntime::iOS:
192 case ObjCRuntime::WatchOS:
193 ObjCRuntime = CreateMacObjCRuntime(*this);
196 llvm_unreachable("bad runtime kind");
199 void CodeGenModule::createOpenCLRuntime() {
200 OpenCLRuntime = new CGOpenCLRuntime(*this);
203 void CodeGenModule::createOpenMPRuntime() {
204 OpenMPRuntime = new CGOpenMPRuntime(*this);
207 void CodeGenModule::createCUDARuntime() {
208 CUDARuntime = CreateNVCUDARuntime(*this);
211 void CodeGenModule::addReplacement(StringRef Name, llvm::Constant *C) {
212 Replacements[Name] = C;
215 void CodeGenModule::applyReplacements() {
216 for (auto &I : Replacements) {
217 StringRef MangledName = I.first();
218 llvm::Constant *Replacement = I.second;
219 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
222 auto *OldF = cast<llvm::Function>(Entry);
223 auto *NewF = dyn_cast<llvm::Function>(Replacement);
225 if (auto *Alias = dyn_cast<llvm::GlobalAlias>(Replacement)) {
226 NewF = dyn_cast<llvm::Function>(Alias->getAliasee());
228 auto *CE = cast<llvm::ConstantExpr>(Replacement);
229 assert(CE->getOpcode() == llvm::Instruction::BitCast ||
230 CE->getOpcode() == llvm::Instruction::GetElementPtr);
231 NewF = dyn_cast<llvm::Function>(CE->getOperand(0));
235 // Replace old with new, but keep the old order.
236 OldF->replaceAllUsesWith(Replacement);
238 NewF->removeFromParent();
239 OldF->getParent()->getFunctionList().insertAfter(OldF->getIterator(),
242 OldF->eraseFromParent();
246 void CodeGenModule::addGlobalValReplacement(llvm::GlobalValue *GV, llvm::Constant *C) {
247 GlobalValReplacements.push_back(std::make_pair(GV, C));
250 void CodeGenModule::applyGlobalValReplacements() {
251 for (auto &I : GlobalValReplacements) {
252 llvm::GlobalValue *GV = I.first;
253 llvm::Constant *C = I.second;
255 GV->replaceAllUsesWith(C);
256 GV->eraseFromParent();
260 // This is only used in aliases that we created and we know they have a
262 static const llvm::GlobalObject *getAliasedGlobal(const llvm::GlobalAlias &GA) {
263 llvm::SmallPtrSet<const llvm::GlobalAlias*, 4> Visited;
264 const llvm::Constant *C = &GA;
266 C = C->stripPointerCasts();
267 if (auto *GO = dyn_cast<llvm::GlobalObject>(C))
269 // stripPointerCasts will not walk over weak aliases.
270 auto *GA2 = dyn_cast<llvm::GlobalAlias>(C);
273 if (!Visited.insert(GA2).second)
275 C = GA2->getAliasee();
279 void CodeGenModule::checkAliases() {
280 // Check if the constructed aliases are well formed. It is really unfortunate
281 // that we have to do this in CodeGen, but we only construct mangled names
282 // and aliases during codegen.
284 DiagnosticsEngine &Diags = getDiags();
285 for (const GlobalDecl &GD : Aliases) {
286 const auto *D = cast<ValueDecl>(GD.getDecl());
287 const AliasAttr *AA = D->getAttr<AliasAttr>();
288 StringRef MangledName = getMangledName(GD);
289 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
290 auto *Alias = cast<llvm::GlobalAlias>(Entry);
291 const llvm::GlobalValue *GV = getAliasedGlobal(*Alias);
294 Diags.Report(AA->getLocation(), diag::err_cyclic_alias);
295 } else if (GV->isDeclaration()) {
297 Diags.Report(AA->getLocation(), diag::err_alias_to_undefined);
300 llvm::Constant *Aliasee = Alias->getAliasee();
301 llvm::GlobalValue *AliaseeGV;
302 if (auto CE = dyn_cast<llvm::ConstantExpr>(Aliasee))
303 AliaseeGV = cast<llvm::GlobalValue>(CE->getOperand(0));
305 AliaseeGV = cast<llvm::GlobalValue>(Aliasee);
307 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) {
308 StringRef AliasSection = SA->getName();
309 if (AliasSection != AliaseeGV->getSection())
310 Diags.Report(SA->getLocation(), diag::warn_alias_with_section)
314 // We have to handle alias to weak aliases in here. LLVM itself disallows
315 // this since the object semantics would not match the IL one. For
316 // compatibility with gcc we implement it by just pointing the alias
317 // to its aliasee's aliasee. We also warn, since the user is probably
318 // expecting the link to be weak.
319 if (auto GA = dyn_cast<llvm::GlobalAlias>(AliaseeGV)) {
320 if (GA->mayBeOverridden()) {
321 Diags.Report(AA->getLocation(), diag::warn_alias_to_weak_alias)
322 << GV->getName() << GA->getName();
323 Aliasee = llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
324 GA->getAliasee(), Alias->getType());
325 Alias->setAliasee(Aliasee);
332 for (const GlobalDecl &GD : Aliases) {
333 StringRef MangledName = getMangledName(GD);
334 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
335 auto *Alias = cast<llvm::GlobalAlias>(Entry);
336 Alias->replaceAllUsesWith(llvm::UndefValue::get(Alias->getType()));
337 Alias->eraseFromParent();
341 void CodeGenModule::clear() {
342 DeferredDeclsToEmit.clear();
344 OpenMPRuntime->clear();
347 void InstrProfStats::reportDiagnostics(DiagnosticsEngine &Diags,
348 StringRef MainFile) {
349 if (!hasDiagnostics())
351 if (VisitedInMainFile > 0 && VisitedInMainFile == MissingInMainFile) {
352 if (MainFile.empty())
353 MainFile = "<stdin>";
354 Diags.Report(diag::warn_profile_data_unprofiled) << MainFile;
356 Diags.Report(diag::warn_profile_data_out_of_date) << Visited << Missing
360 void CodeGenModule::Release() {
362 applyGlobalValReplacements();
365 EmitCXXGlobalInitFunc();
366 EmitCXXGlobalDtorFunc();
367 EmitCXXThreadLocalInitFunc();
369 if (llvm::Function *ObjCInitFunction = ObjCRuntime->ModuleInitFunction())
370 AddGlobalCtor(ObjCInitFunction);
371 if (Context.getLangOpts().CUDA && !Context.getLangOpts().CUDAIsDevice &&
373 if (llvm::Function *CudaCtorFunction = CUDARuntime->makeModuleCtorFunction())
374 AddGlobalCtor(CudaCtorFunction);
375 if (llvm::Function *CudaDtorFunction = CUDARuntime->makeModuleDtorFunction())
376 AddGlobalDtor(CudaDtorFunction);
379 getModule().setMaximumFunctionCount(PGOReader->getMaximumFunctionCount());
380 if (PGOStats.hasDiagnostics())
381 PGOStats.reportDiagnostics(getDiags(), getCodeGenOpts().MainFileName);
383 EmitCtorList(GlobalCtors, "llvm.global_ctors");
384 EmitCtorList(GlobalDtors, "llvm.global_dtors");
385 EmitGlobalAnnotations();
386 EmitStaticExternCAliases();
387 EmitDeferredUnusedCoverageMappings();
389 CoverageMapping->emit();
392 if (CodeGenOpts.Autolink &&
393 (Context.getLangOpts().Modules || !LinkerOptionsMetadata.empty())) {
394 EmitModuleLinkOptions();
396 if (CodeGenOpts.DwarfVersion) {
397 // We actually want the latest version when there are conflicts.
398 // We can change from Warning to Latest if such mode is supported.
399 getModule().addModuleFlag(llvm::Module::Warning, "Dwarf Version",
400 CodeGenOpts.DwarfVersion);
402 if (CodeGenOpts.EmitCodeView) {
403 // Indicate that we want CodeView in the metadata.
404 getModule().addModuleFlag(llvm::Module::Warning, "CodeView", 1);
406 if (CodeGenOpts.OptimizationLevel > 0 && CodeGenOpts.StrictVTablePointers) {
407 // We don't support LTO with 2 with different StrictVTablePointers
408 // FIXME: we could support it by stripping all the information introduced
409 // by StrictVTablePointers.
411 getModule().addModuleFlag(llvm::Module::Error, "StrictVTablePointers",1);
413 llvm::Metadata *Ops[2] = {
414 llvm::MDString::get(VMContext, "StrictVTablePointers"),
415 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
416 llvm::Type::getInt32Ty(VMContext), 1))};
418 getModule().addModuleFlag(llvm::Module::Require,
419 "StrictVTablePointersRequirement",
420 llvm::MDNode::get(VMContext, Ops));
423 // We support a single version in the linked module. The LLVM
424 // parser will drop debug info with a different version number
425 // (and warn about it, too).
426 getModule().addModuleFlag(llvm::Module::Warning, "Debug Info Version",
427 llvm::DEBUG_METADATA_VERSION);
429 // We need to record the widths of enums and wchar_t, so that we can generate
430 // the correct build attributes in the ARM backend.
431 llvm::Triple::ArchType Arch = Context.getTargetInfo().getTriple().getArch();
432 if ( Arch == llvm::Triple::arm
433 || Arch == llvm::Triple::armeb
434 || Arch == llvm::Triple::thumb
435 || Arch == llvm::Triple::thumbeb) {
436 // Width of wchar_t in bytes
437 uint64_t WCharWidth =
438 Context.getTypeSizeInChars(Context.getWideCharType()).getQuantity();
439 getModule().addModuleFlag(llvm::Module::Error, "wchar_size", WCharWidth);
441 // The minimum width of an enum in bytes
442 uint64_t EnumWidth = Context.getLangOpts().ShortEnums ? 1 : 4;
443 getModule().addModuleFlag(llvm::Module::Error, "min_enum_size", EnumWidth);
446 if (CodeGenOpts.SanitizeCfiCrossDso) {
447 // Indicate that we want cross-DSO control flow integrity checks.
448 getModule().addModuleFlag(llvm::Module::Override, "Cross-DSO CFI", 1);
451 if (uint32_t PLevel = Context.getLangOpts().PICLevel) {
452 llvm::PICLevel::Level PL = llvm::PICLevel::Default;
455 case 1: PL = llvm::PICLevel::Small; break;
456 case 2: PL = llvm::PICLevel::Large; break;
457 default: llvm_unreachable("Invalid PIC Level");
460 getModule().setPICLevel(PL);
463 SimplifyPersonality();
465 if (getCodeGenOpts().EmitDeclMetadata)
468 if (getCodeGenOpts().EmitGcovArcs || getCodeGenOpts().EmitGcovNotes)
472 DebugInfo->finalize();
474 EmitVersionIdentMetadata();
476 EmitTargetMetadata();
479 void CodeGenModule::UpdateCompletedType(const TagDecl *TD) {
480 // Make sure that this type is translated.
481 Types.UpdateCompletedType(TD);
484 llvm::MDNode *CodeGenModule::getTBAAInfo(QualType QTy) {
487 return TBAA->getTBAAInfo(QTy);
490 llvm::MDNode *CodeGenModule::getTBAAInfoForVTablePtr() {
493 return TBAA->getTBAAInfoForVTablePtr();
496 llvm::MDNode *CodeGenModule::getTBAAStructInfo(QualType QTy) {
499 return TBAA->getTBAAStructInfo(QTy);
502 llvm::MDNode *CodeGenModule::getTBAAStructTagInfo(QualType BaseTy,
503 llvm::MDNode *AccessN,
507 return TBAA->getTBAAStructTagInfo(BaseTy, AccessN, O);
510 /// Decorate the instruction with a TBAA tag. For both scalar TBAA
511 /// and struct-path aware TBAA, the tag has the same format:
512 /// base type, access type and offset.
513 /// When ConvertTypeToTag is true, we create a tag based on the scalar type.
514 void CodeGenModule::DecorateInstructionWithTBAA(llvm::Instruction *Inst,
515 llvm::MDNode *TBAAInfo,
516 bool ConvertTypeToTag) {
517 if (ConvertTypeToTag && TBAA)
518 Inst->setMetadata(llvm::LLVMContext::MD_tbaa,
519 TBAA->getTBAAScalarTagInfo(TBAAInfo));
521 Inst->setMetadata(llvm::LLVMContext::MD_tbaa, TBAAInfo);
524 void CodeGenModule::DecorateInstructionWithInvariantGroup(
525 llvm::Instruction *I, const CXXRecordDecl *RD) {
526 llvm::Metadata *MD = CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0));
527 auto *MetaDataNode = dyn_cast<llvm::MDNode>(MD);
528 // Check if we have to wrap MDString in MDNode.
530 MetaDataNode = llvm::MDNode::get(getLLVMContext(), MD);
531 I->setMetadata(llvm::LLVMContext::MD_invariant_group, MetaDataNode);
534 void CodeGenModule::Error(SourceLocation loc, StringRef message) {
535 unsigned diagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, "%0");
536 getDiags().Report(Context.getFullLoc(loc), diagID) << message;
539 /// ErrorUnsupported - Print out an error that codegen doesn't support the
540 /// specified stmt yet.
541 void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type) {
542 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error,
543 "cannot compile this %0 yet");
544 std::string Msg = Type;
545 getDiags().Report(Context.getFullLoc(S->getLocStart()), DiagID)
546 << Msg << S->getSourceRange();
549 /// ErrorUnsupported - Print out an error that codegen doesn't support the
550 /// specified decl yet.
551 void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type) {
552 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error,
553 "cannot compile this %0 yet");
554 std::string Msg = Type;
555 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg;
558 llvm::ConstantInt *CodeGenModule::getSize(CharUnits size) {
559 return llvm::ConstantInt::get(SizeTy, size.getQuantity());
562 void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV,
563 const NamedDecl *D) const {
564 // Internal definitions always have default visibility.
565 if (GV->hasLocalLinkage()) {
566 GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
570 // Set visibility for definitions.
571 LinkageInfo LV = D->getLinkageAndVisibility();
572 if (LV.isVisibilityExplicit() || !GV->hasAvailableExternallyLinkage())
573 GV->setVisibility(GetLLVMVisibility(LV.getVisibility()));
576 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(StringRef S) {
577 return llvm::StringSwitch<llvm::GlobalVariable::ThreadLocalMode>(S)
578 .Case("global-dynamic", llvm::GlobalVariable::GeneralDynamicTLSModel)
579 .Case("local-dynamic", llvm::GlobalVariable::LocalDynamicTLSModel)
580 .Case("initial-exec", llvm::GlobalVariable::InitialExecTLSModel)
581 .Case("local-exec", llvm::GlobalVariable::LocalExecTLSModel);
584 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(
585 CodeGenOptions::TLSModel M) {
587 case CodeGenOptions::GeneralDynamicTLSModel:
588 return llvm::GlobalVariable::GeneralDynamicTLSModel;
589 case CodeGenOptions::LocalDynamicTLSModel:
590 return llvm::GlobalVariable::LocalDynamicTLSModel;
591 case CodeGenOptions::InitialExecTLSModel:
592 return llvm::GlobalVariable::InitialExecTLSModel;
593 case CodeGenOptions::LocalExecTLSModel:
594 return llvm::GlobalVariable::LocalExecTLSModel;
596 llvm_unreachable("Invalid TLS model!");
599 void CodeGenModule::setTLSMode(llvm::GlobalValue *GV, const VarDecl &D) const {
600 assert(D.getTLSKind() && "setting TLS mode on non-TLS var!");
602 llvm::GlobalValue::ThreadLocalMode TLM;
603 TLM = GetLLVMTLSModel(CodeGenOpts.getDefaultTLSModel());
605 // Override the TLS model if it is explicitly specified.
606 if (const TLSModelAttr *Attr = D.getAttr<TLSModelAttr>()) {
607 TLM = GetLLVMTLSModel(Attr->getModel());
610 GV->setThreadLocalMode(TLM);
613 StringRef CodeGenModule::getMangledName(GlobalDecl GD) {
614 StringRef &FoundStr = MangledDeclNames[GD.getCanonicalDecl()];
615 if (!FoundStr.empty())
618 const auto *ND = cast<NamedDecl>(GD.getDecl());
619 SmallString<256> Buffer;
621 if (getCXXABI().getMangleContext().shouldMangleDeclName(ND)) {
622 llvm::raw_svector_ostream Out(Buffer);
623 if (const auto *D = dyn_cast<CXXConstructorDecl>(ND))
624 getCXXABI().getMangleContext().mangleCXXCtor(D, GD.getCtorType(), Out);
625 else if (const auto *D = dyn_cast<CXXDestructorDecl>(ND))
626 getCXXABI().getMangleContext().mangleCXXDtor(D, GD.getDtorType(), Out);
628 getCXXABI().getMangleContext().mangleName(ND, Out);
631 IdentifierInfo *II = ND->getIdentifier();
632 assert(II && "Attempt to mangle unnamed decl.");
636 // Keep the first result in the case of a mangling collision.
637 auto Result = Manglings.insert(std::make_pair(Str, GD));
638 return FoundStr = Result.first->first();
641 StringRef CodeGenModule::getBlockMangledName(GlobalDecl GD,
642 const BlockDecl *BD) {
643 MangleContext &MangleCtx = getCXXABI().getMangleContext();
644 const Decl *D = GD.getDecl();
646 SmallString<256> Buffer;
647 llvm::raw_svector_ostream Out(Buffer);
649 MangleCtx.mangleGlobalBlock(BD,
650 dyn_cast_or_null<VarDecl>(initializedGlobalDecl.getDecl()), Out);
651 else if (const auto *CD = dyn_cast<CXXConstructorDecl>(D))
652 MangleCtx.mangleCtorBlock(CD, GD.getCtorType(), BD, Out);
653 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(D))
654 MangleCtx.mangleDtorBlock(DD, GD.getDtorType(), BD, Out);
656 MangleCtx.mangleBlock(cast<DeclContext>(D), BD, Out);
658 auto Result = Manglings.insert(std::make_pair(Out.str(), BD));
659 return Result.first->first();
662 llvm::GlobalValue *CodeGenModule::GetGlobalValue(StringRef Name) {
663 return getModule().getNamedValue(Name);
666 /// AddGlobalCtor - Add a function to the list that will be called before
668 void CodeGenModule::AddGlobalCtor(llvm::Function *Ctor, int Priority,
669 llvm::Constant *AssociatedData) {
670 // FIXME: Type coercion of void()* types.
671 GlobalCtors.push_back(Structor(Priority, Ctor, AssociatedData));
674 /// AddGlobalDtor - Add a function to the list that will be called
675 /// when the module is unloaded.
676 void CodeGenModule::AddGlobalDtor(llvm::Function *Dtor, int Priority) {
677 // FIXME: Type coercion of void()* types.
678 GlobalDtors.push_back(Structor(Priority, Dtor, nullptr));
681 void CodeGenModule::EmitCtorList(const CtorList &Fns, const char *GlobalName) {
682 // Ctor function type is void()*.
683 llvm::FunctionType* CtorFTy = llvm::FunctionType::get(VoidTy, false);
684 llvm::Type *CtorPFTy = llvm::PointerType::getUnqual(CtorFTy);
686 // Get the type of a ctor entry, { i32, void ()*, i8* }.
687 llvm::StructType *CtorStructTy = llvm::StructType::get(
688 Int32Ty, llvm::PointerType::getUnqual(CtorFTy), VoidPtrTy, nullptr);
690 // Construct the constructor and destructor arrays.
691 SmallVector<llvm::Constant *, 8> Ctors;
692 for (const auto &I : Fns) {
693 llvm::Constant *S[] = {
694 llvm::ConstantInt::get(Int32Ty, I.Priority, false),
695 llvm::ConstantExpr::getBitCast(I.Initializer, CtorPFTy),
697 ? llvm::ConstantExpr::getBitCast(I.AssociatedData, VoidPtrTy)
698 : llvm::Constant::getNullValue(VoidPtrTy))};
699 Ctors.push_back(llvm::ConstantStruct::get(CtorStructTy, S));
702 if (!Ctors.empty()) {
703 llvm::ArrayType *AT = llvm::ArrayType::get(CtorStructTy, Ctors.size());
704 new llvm::GlobalVariable(TheModule, AT, false,
705 llvm::GlobalValue::AppendingLinkage,
706 llvm::ConstantArray::get(AT, Ctors),
711 llvm::GlobalValue::LinkageTypes
712 CodeGenModule::getFunctionLinkage(GlobalDecl GD) {
713 const auto *D = cast<FunctionDecl>(GD.getDecl());
715 GVALinkage Linkage = getContext().GetGVALinkageForFunction(D);
717 if (isa<CXXDestructorDecl>(D) &&
718 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
720 // Destructor variants in the Microsoft C++ ABI are always internal or
721 // linkonce_odr thunks emitted on an as-needed basis.
722 return Linkage == GVA_Internal ? llvm::GlobalValue::InternalLinkage
723 : llvm::GlobalValue::LinkOnceODRLinkage;
726 return getLLVMLinkageForDeclarator(D, Linkage, /*isConstantVariable=*/false);
729 void CodeGenModule::setFunctionDLLStorageClass(GlobalDecl GD, llvm::Function *F) {
730 const auto *FD = cast<FunctionDecl>(GD.getDecl());
732 if (const auto *Dtor = dyn_cast_or_null<CXXDestructorDecl>(FD)) {
733 if (getCXXABI().useThunkForDtorVariant(Dtor, GD.getDtorType())) {
734 // Don't dllexport/import destructor thunks.
735 F->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
740 if (FD->hasAttr<DLLImportAttr>())
741 F->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
742 else if (FD->hasAttr<DLLExportAttr>())
743 F->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
745 F->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass);
749 CodeGenModule::CreateCfiIdForTypeMetadata(llvm::Metadata *MD) {
750 llvm::MDString *MDS = dyn_cast<llvm::MDString>(MD);
751 if (!MDS) return nullptr;
754 llvm::MD5::MD5Result result;
755 md5.update(MDS->getString());
758 for (int i = 0; i < 8; ++i)
759 id |= static_cast<uint64_t>(result[i]) << (i * 8);
760 return llvm::ConstantInt::get(Int64Ty, id);
763 void CodeGenModule::setFunctionDefinitionAttributes(const FunctionDecl *D,
765 setNonAliasAttributes(D, F);
768 void CodeGenModule::SetLLVMFunctionAttributes(const Decl *D,
769 const CGFunctionInfo &Info,
771 unsigned CallingConv;
772 AttributeListType AttributeList;
773 ConstructAttributeList(Info, D, AttributeList, CallingConv, false);
774 F->setAttributes(llvm::AttributeSet::get(getLLVMContext(), AttributeList));
775 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
778 /// Determines whether the language options require us to model
779 /// unwind exceptions. We treat -fexceptions as mandating this
780 /// except under the fragile ObjC ABI with only ObjC exceptions
781 /// enabled. This means, for example, that C with -fexceptions
783 static bool hasUnwindExceptions(const LangOptions &LangOpts) {
784 // If exceptions are completely disabled, obviously this is false.
785 if (!LangOpts.Exceptions) return false;
787 // If C++ exceptions are enabled, this is true.
788 if (LangOpts.CXXExceptions) return true;
790 // If ObjC exceptions are enabled, this depends on the ABI.
791 if (LangOpts.ObjCExceptions) {
792 return LangOpts.ObjCRuntime.hasUnwindExceptions();
798 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
802 if (CodeGenOpts.UnwindTables)
803 B.addAttribute(llvm::Attribute::UWTable);
805 if (!hasUnwindExceptions(LangOpts))
806 B.addAttribute(llvm::Attribute::NoUnwind);
808 if (LangOpts.getStackProtector() == LangOptions::SSPOn)
809 B.addAttribute(llvm::Attribute::StackProtect);
810 else if (LangOpts.getStackProtector() == LangOptions::SSPStrong)
811 B.addAttribute(llvm::Attribute::StackProtectStrong);
812 else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
813 B.addAttribute(llvm::Attribute::StackProtectReq);
816 F->addAttributes(llvm::AttributeSet::FunctionIndex,
817 llvm::AttributeSet::get(
819 llvm::AttributeSet::FunctionIndex, B));
823 if (D->hasAttr<NakedAttr>()) {
824 // Naked implies noinline: we should not be inlining such functions.
825 B.addAttribute(llvm::Attribute::Naked);
826 B.addAttribute(llvm::Attribute::NoInline);
827 } else if (D->hasAttr<NoDuplicateAttr>()) {
828 B.addAttribute(llvm::Attribute::NoDuplicate);
829 } else if (D->hasAttr<NoInlineAttr>()) {
830 B.addAttribute(llvm::Attribute::NoInline);
831 } else if (D->hasAttr<AlwaysInlineAttr>() &&
832 !F->getAttributes().hasAttribute(llvm::AttributeSet::FunctionIndex,
833 llvm::Attribute::NoInline)) {
834 // (noinline wins over always_inline, and we can't specify both in IR)
835 B.addAttribute(llvm::Attribute::AlwaysInline);
838 if (D->hasAttr<ColdAttr>()) {
839 if (!D->hasAttr<OptimizeNoneAttr>())
840 B.addAttribute(llvm::Attribute::OptimizeForSize);
841 B.addAttribute(llvm::Attribute::Cold);
844 if (D->hasAttr<MinSizeAttr>())
845 B.addAttribute(llvm::Attribute::MinSize);
847 F->addAttributes(llvm::AttributeSet::FunctionIndex,
848 llvm::AttributeSet::get(
849 F->getContext(), llvm::AttributeSet::FunctionIndex, B));
851 if (D->hasAttr<OptimizeNoneAttr>()) {
852 // OptimizeNone implies noinline; we should not be inlining such functions.
853 F->addFnAttr(llvm::Attribute::OptimizeNone);
854 F->addFnAttr(llvm::Attribute::NoInline);
856 // OptimizeNone wins over OptimizeForSize, MinSize, AlwaysInline.
857 F->removeFnAttr(llvm::Attribute::OptimizeForSize);
858 F->removeFnAttr(llvm::Attribute::MinSize);
859 assert(!F->hasFnAttribute(llvm::Attribute::AlwaysInline) &&
860 "OptimizeNone and AlwaysInline on same function!");
862 // Attribute 'inlinehint' has no effect on 'optnone' functions.
863 // Explicitly remove it from the set of function attributes.
864 F->removeFnAttr(llvm::Attribute::InlineHint);
867 if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D))
868 F->setUnnamedAddr(true);
869 else if (const auto *MD = dyn_cast<CXXMethodDecl>(D))
871 F->setUnnamedAddr(true);
873 unsigned alignment = D->getMaxAlignment() / Context.getCharWidth();
875 F->setAlignment(alignment);
877 // Some C++ ABIs require 2-byte alignment for member functions, in order to
878 // reserve a bit for differentiating between virtual and non-virtual member
879 // functions. If the current target's C++ ABI requires this and this is a
880 // member function, set its alignment accordingly.
881 if (getTarget().getCXXABI().areMemberFunctionsAligned()) {
882 if (F->getAlignment() < 2 && isa<CXXMethodDecl>(D))
887 void CodeGenModule::SetCommonAttributes(const Decl *D,
888 llvm::GlobalValue *GV) {
889 if (const auto *ND = dyn_cast_or_null<NamedDecl>(D))
890 setGlobalVisibility(GV, ND);
892 GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
894 if (D && D->hasAttr<UsedAttr>())
898 void CodeGenModule::setAliasAttributes(const Decl *D,
899 llvm::GlobalValue *GV) {
900 SetCommonAttributes(D, GV);
902 // Process the dllexport attribute based on whether the original definition
903 // (not necessarily the aliasee) was exported.
904 if (D->hasAttr<DLLExportAttr>())
905 GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
908 void CodeGenModule::setNonAliasAttributes(const Decl *D,
909 llvm::GlobalObject *GO) {
910 SetCommonAttributes(D, GO);
913 if (const SectionAttr *SA = D->getAttr<SectionAttr>())
914 GO->setSection(SA->getName());
916 getTargetCodeGenInfo().setTargetAttributes(D, GO, *this);
919 void CodeGenModule::SetInternalFunctionAttributes(const Decl *D,
921 const CGFunctionInfo &FI) {
922 SetLLVMFunctionAttributes(D, FI, F);
923 SetLLVMFunctionAttributesForDefinition(D, F);
925 F->setLinkage(llvm::Function::InternalLinkage);
927 setNonAliasAttributes(D, F);
930 static void setLinkageAndVisibilityForGV(llvm::GlobalValue *GV,
931 const NamedDecl *ND) {
932 // Set linkage and visibility in case we never see a definition.
933 LinkageInfo LV = ND->getLinkageAndVisibility();
934 if (LV.getLinkage() != ExternalLinkage) {
935 // Don't set internal linkage on declarations.
937 if (ND->hasAttr<DLLImportAttr>()) {
938 GV->setLinkage(llvm::GlobalValue::ExternalLinkage);
939 GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
940 } else if (ND->hasAttr<DLLExportAttr>()) {
941 GV->setLinkage(llvm::GlobalValue::ExternalLinkage);
942 GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
943 } else if (ND->hasAttr<WeakAttr>() || ND->isWeakImported()) {
944 // "extern_weak" is overloaded in LLVM; we probably should have
945 // separate linkage types for this.
946 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage);
949 // Set visibility on a declaration only if it's explicit.
950 if (LV.isVisibilityExplicit())
951 GV->setVisibility(CodeGenModule::GetLLVMVisibility(LV.getVisibility()));
955 void CodeGenModule::CreateFunctionBitSetEntry(const FunctionDecl *FD,
957 // Only if we are checking indirect calls.
958 if (!LangOpts.Sanitize.has(SanitizerKind::CFIICall))
961 // Non-static class methods are handled via vtable pointer checks elsewhere.
962 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic())
965 // Additionally, if building with cross-DSO support...
966 if (CodeGenOpts.SanitizeCfiCrossDso) {
967 // Don't emit entries for function declarations. In cross-DSO mode these are
968 // handled with better precision at run time.
971 // Skip available_externally functions. They won't be codegen'ed in the
972 // current module anyway.
973 if (getContext().GetGVALinkageForFunction(FD) == GVA_AvailableExternally)
977 llvm::NamedMDNode *BitsetsMD =
978 getModule().getOrInsertNamedMetadata("llvm.bitsets");
980 llvm::Metadata *MD = CreateMetadataIdentifierForType(FD->getType());
981 llvm::Metadata *BitsetOps[] = {
982 MD, llvm::ConstantAsMetadata::get(F),
983 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(Int64Ty, 0))};
984 BitsetsMD->addOperand(llvm::MDTuple::get(getLLVMContext(), BitsetOps));
986 // Emit a hash-based bit set entry for cross-DSO calls.
987 if (CodeGenOpts.SanitizeCfiCrossDso) {
988 if (auto TypeId = CreateCfiIdForTypeMetadata(MD)) {
989 llvm::Metadata *BitsetOps2[] = {
990 llvm::ConstantAsMetadata::get(TypeId),
991 llvm::ConstantAsMetadata::get(F),
992 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(Int64Ty, 0))};
993 BitsetsMD->addOperand(llvm::MDTuple::get(getLLVMContext(), BitsetOps2));
998 void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, llvm::Function *F,
999 bool IsIncompleteFunction,
1001 if (llvm::Intrinsic::ID IID = F->getIntrinsicID()) {
1002 // If this is an intrinsic function, set the function's attributes
1003 // to the intrinsic's attributes.
1004 F->setAttributes(llvm::Intrinsic::getAttributes(getLLVMContext(), IID));
1008 const auto *FD = cast<FunctionDecl>(GD.getDecl());
1010 if (!IsIncompleteFunction)
1011 SetLLVMFunctionAttributes(FD, getTypes().arrangeGlobalDeclaration(GD), F);
1013 // Add the Returned attribute for "this", except for iOS 5 and earlier
1014 // where substantial code, including the libstdc++ dylib, was compiled with
1015 // GCC and does not actually return "this".
1016 if (!IsThunk && getCXXABI().HasThisReturn(GD) &&
1017 !(getTarget().getTriple().isiOS() &&
1018 getTarget().getTriple().isOSVersionLT(6))) {
1019 assert(!F->arg_empty() &&
1020 F->arg_begin()->getType()
1021 ->canLosslesslyBitCastTo(F->getReturnType()) &&
1022 "unexpected this return");
1023 F->addAttribute(1, llvm::Attribute::Returned);
1026 // Only a few attributes are set on declarations; these may later be
1027 // overridden by a definition.
1029 setLinkageAndVisibilityForGV(F, FD);
1031 if (const SectionAttr *SA = FD->getAttr<SectionAttr>())
1032 F->setSection(SA->getName());
1034 // A replaceable global allocation function does not act like a builtin by
1035 // default, only if it is invoked by a new-expression or delete-expression.
1036 if (FD->isReplaceableGlobalAllocationFunction())
1037 F->addAttribute(llvm::AttributeSet::FunctionIndex,
1038 llvm::Attribute::NoBuiltin);
1040 CreateFunctionBitSetEntry(FD, F);
1043 void CodeGenModule::addUsedGlobal(llvm::GlobalValue *GV) {
1044 assert(!GV->isDeclaration() &&
1045 "Only globals with definition can force usage.");
1046 LLVMUsed.emplace_back(GV);
1049 void CodeGenModule::addCompilerUsedGlobal(llvm::GlobalValue *GV) {
1050 assert(!GV->isDeclaration() &&
1051 "Only globals with definition can force usage.");
1052 LLVMCompilerUsed.emplace_back(GV);
1055 static void emitUsed(CodeGenModule &CGM, StringRef Name,
1056 std::vector<llvm::WeakVH> &List) {
1057 // Don't create llvm.used if there is no need.
1061 // Convert List to what ConstantArray needs.
1062 SmallVector<llvm::Constant*, 8> UsedArray;
1063 UsedArray.resize(List.size());
1064 for (unsigned i = 0, e = List.size(); i != e; ++i) {
1066 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
1067 cast<llvm::Constant>(&*List[i]), CGM.Int8PtrTy);
1070 if (UsedArray.empty())
1072 llvm::ArrayType *ATy = llvm::ArrayType::get(CGM.Int8PtrTy, UsedArray.size());
1074 auto *GV = new llvm::GlobalVariable(
1075 CGM.getModule(), ATy, false, llvm::GlobalValue::AppendingLinkage,
1076 llvm::ConstantArray::get(ATy, UsedArray), Name);
1078 GV->setSection("llvm.metadata");
1081 void CodeGenModule::emitLLVMUsed() {
1082 emitUsed(*this, "llvm.used", LLVMUsed);
1083 emitUsed(*this, "llvm.compiler.used", LLVMCompilerUsed);
1086 void CodeGenModule::AppendLinkerOptions(StringRef Opts) {
1087 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opts);
1088 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
1091 void CodeGenModule::AddDetectMismatch(StringRef Name, StringRef Value) {
1092 llvm::SmallString<32> Opt;
1093 getTargetCodeGenInfo().getDetectMismatchOption(Name, Value, Opt);
1094 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt);
1095 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
1098 void CodeGenModule::AddDependentLib(StringRef Lib) {
1099 llvm::SmallString<24> Opt;
1100 getTargetCodeGenInfo().getDependentLibraryOption(Lib, Opt);
1101 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt);
1102 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
1105 /// \brief Add link options implied by the given module, including modules
1106 /// it depends on, using a postorder walk.
1107 static void addLinkOptionsPostorder(CodeGenModule &CGM, Module *Mod,
1108 SmallVectorImpl<llvm::Metadata *> &Metadata,
1109 llvm::SmallPtrSet<Module *, 16> &Visited) {
1110 // Import this module's parent.
1111 if (Mod->Parent && Visited.insert(Mod->Parent).second) {
1112 addLinkOptionsPostorder(CGM, Mod->Parent, Metadata, Visited);
1115 // Import this module's dependencies.
1116 for (unsigned I = Mod->Imports.size(); I > 0; --I) {
1117 if (Visited.insert(Mod->Imports[I - 1]).second)
1118 addLinkOptionsPostorder(CGM, Mod->Imports[I-1], Metadata, Visited);
1121 // Add linker options to link against the libraries/frameworks
1122 // described by this module.
1123 llvm::LLVMContext &Context = CGM.getLLVMContext();
1124 for (unsigned I = Mod->LinkLibraries.size(); I > 0; --I) {
1125 // Link against a framework. Frameworks are currently Darwin only, so we
1126 // don't to ask TargetCodeGenInfo for the spelling of the linker option.
1127 if (Mod->LinkLibraries[I-1].IsFramework) {
1128 llvm::Metadata *Args[2] = {
1129 llvm::MDString::get(Context, "-framework"),
1130 llvm::MDString::get(Context, Mod->LinkLibraries[I - 1].Library)};
1132 Metadata.push_back(llvm::MDNode::get(Context, Args));
1136 // Link against a library.
1137 llvm::SmallString<24> Opt;
1138 CGM.getTargetCodeGenInfo().getDependentLibraryOption(
1139 Mod->LinkLibraries[I-1].Library, Opt);
1140 auto *OptString = llvm::MDString::get(Context, Opt);
1141 Metadata.push_back(llvm::MDNode::get(Context, OptString));
1145 void CodeGenModule::EmitModuleLinkOptions() {
1146 // Collect the set of all of the modules we want to visit to emit link
1147 // options, which is essentially the imported modules and all of their
1148 // non-explicit child modules.
1149 llvm::SetVector<clang::Module *> LinkModules;
1150 llvm::SmallPtrSet<clang::Module *, 16> Visited;
1151 SmallVector<clang::Module *, 16> Stack;
1153 // Seed the stack with imported modules.
1154 for (Module *M : ImportedModules)
1155 if (Visited.insert(M).second)
1158 // Find all of the modules to import, making a little effort to prune
1159 // non-leaf modules.
1160 while (!Stack.empty()) {
1161 clang::Module *Mod = Stack.pop_back_val();
1163 bool AnyChildren = false;
1165 // Visit the submodules of this module.
1166 for (clang::Module::submodule_iterator Sub = Mod->submodule_begin(),
1167 SubEnd = Mod->submodule_end();
1168 Sub != SubEnd; ++Sub) {
1169 // Skip explicit children; they need to be explicitly imported to be
1171 if ((*Sub)->IsExplicit)
1174 if (Visited.insert(*Sub).second) {
1175 Stack.push_back(*Sub);
1180 // We didn't find any children, so add this module to the list of
1181 // modules to link against.
1183 LinkModules.insert(Mod);
1187 // Add link options for all of the imported modules in reverse topological
1188 // order. We don't do anything to try to order import link flags with respect
1189 // to linker options inserted by things like #pragma comment().
1190 SmallVector<llvm::Metadata *, 16> MetadataArgs;
1192 for (Module *M : LinkModules)
1193 if (Visited.insert(M).second)
1194 addLinkOptionsPostorder(*this, M, MetadataArgs, Visited);
1195 std::reverse(MetadataArgs.begin(), MetadataArgs.end());
1196 LinkerOptionsMetadata.append(MetadataArgs.begin(), MetadataArgs.end());
1198 // Add the linker options metadata flag.
1199 getModule().addModuleFlag(llvm::Module::AppendUnique, "Linker Options",
1200 llvm::MDNode::get(getLLVMContext(),
1201 LinkerOptionsMetadata));
1204 void CodeGenModule::EmitDeferred() {
1205 // Emit code for any potentially referenced deferred decls. Since a
1206 // previously unused static decl may become used during the generation of code
1207 // for a static function, iterate until no changes are made.
1209 if (!DeferredVTables.empty()) {
1210 EmitDeferredVTables();
1212 // Emitting a v-table doesn't directly cause more v-tables to
1213 // become deferred, although it can cause functions to be
1214 // emitted that then need those v-tables.
1215 assert(DeferredVTables.empty());
1218 // Stop if we're out of both deferred v-tables and deferred declarations.
1219 if (DeferredDeclsToEmit.empty())
1222 // Grab the list of decls to emit. If EmitGlobalDefinition schedules more
1223 // work, it will not interfere with this.
1224 std::vector<DeferredGlobal> CurDeclsToEmit;
1225 CurDeclsToEmit.swap(DeferredDeclsToEmit);
1227 for (DeferredGlobal &G : CurDeclsToEmit) {
1228 GlobalDecl D = G.GD;
1229 llvm::GlobalValue *GV = G.GV;
1232 // We should call GetAddrOfGlobal with IsForDefinition set to true in order
1233 // to get GlobalValue with exactly the type we need, not something that
1234 // might had been created for another decl with the same mangled name but
1236 // FIXME: Support for variables is not implemented yet.
1237 if (isa<FunctionDecl>(D.getDecl()))
1238 GV = cast<llvm::GlobalValue>(GetAddrOfGlobal(D, /*IsForDefinition=*/true));
1241 GV = GetGlobalValue(getMangledName(D));
1243 // Check to see if we've already emitted this. This is necessary
1244 // for a couple of reasons: first, decls can end up in the
1245 // deferred-decls queue multiple times, and second, decls can end
1246 // up with definitions in unusual ways (e.g. by an extern inline
1247 // function acquiring a strong function redefinition). Just
1248 // ignore these cases.
1249 if (GV && !GV->isDeclaration())
1252 // Otherwise, emit the definition and move on to the next one.
1253 EmitGlobalDefinition(D, GV);
1255 // If we found out that we need to emit more decls, do that recursively.
1256 // This has the advantage that the decls are emitted in a DFS and related
1257 // ones are close together, which is convenient for testing.
1258 if (!DeferredVTables.empty() || !DeferredDeclsToEmit.empty()) {
1260 assert(DeferredVTables.empty() && DeferredDeclsToEmit.empty());
1265 void CodeGenModule::EmitGlobalAnnotations() {
1266 if (Annotations.empty())
1269 // Create a new global variable for the ConstantStruct in the Module.
1270 llvm::Constant *Array = llvm::ConstantArray::get(llvm::ArrayType::get(
1271 Annotations[0]->getType(), Annotations.size()), Annotations);
1272 auto *gv = new llvm::GlobalVariable(getModule(), Array->getType(), false,
1273 llvm::GlobalValue::AppendingLinkage,
1274 Array, "llvm.global.annotations");
1275 gv->setSection(AnnotationSection);
1278 llvm::Constant *CodeGenModule::EmitAnnotationString(StringRef Str) {
1279 llvm::Constant *&AStr = AnnotationStrings[Str];
1283 // Not found yet, create a new global.
1284 llvm::Constant *s = llvm::ConstantDataArray::getString(getLLVMContext(), Str);
1286 new llvm::GlobalVariable(getModule(), s->getType(), true,
1287 llvm::GlobalValue::PrivateLinkage, s, ".str");
1288 gv->setSection(AnnotationSection);
1289 gv->setUnnamedAddr(true);
1294 llvm::Constant *CodeGenModule::EmitAnnotationUnit(SourceLocation Loc) {
1295 SourceManager &SM = getContext().getSourceManager();
1296 PresumedLoc PLoc = SM.getPresumedLoc(Loc);
1298 return EmitAnnotationString(PLoc.getFilename());
1299 return EmitAnnotationString(SM.getBufferName(Loc));
1302 llvm::Constant *CodeGenModule::EmitAnnotationLineNo(SourceLocation L) {
1303 SourceManager &SM = getContext().getSourceManager();
1304 PresumedLoc PLoc = SM.getPresumedLoc(L);
1305 unsigned LineNo = PLoc.isValid() ? PLoc.getLine() :
1306 SM.getExpansionLineNumber(L);
1307 return llvm::ConstantInt::get(Int32Ty, LineNo);
1310 llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV,
1311 const AnnotateAttr *AA,
1313 // Get the globals for file name, annotation, and the line number.
1314 llvm::Constant *AnnoGV = EmitAnnotationString(AA->getAnnotation()),
1315 *UnitGV = EmitAnnotationUnit(L),
1316 *LineNoCst = EmitAnnotationLineNo(L);
1318 // Create the ConstantStruct for the global annotation.
1319 llvm::Constant *Fields[4] = {
1320 llvm::ConstantExpr::getBitCast(GV, Int8PtrTy),
1321 llvm::ConstantExpr::getBitCast(AnnoGV, Int8PtrTy),
1322 llvm::ConstantExpr::getBitCast(UnitGV, Int8PtrTy),
1325 return llvm::ConstantStruct::getAnon(Fields);
1328 void CodeGenModule::AddGlobalAnnotations(const ValueDecl *D,
1329 llvm::GlobalValue *GV) {
1330 assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute");
1331 // Get the struct elements for these annotations.
1332 for (const auto *I : D->specific_attrs<AnnotateAttr>())
1333 Annotations.push_back(EmitAnnotateAttr(GV, I, D->getLocation()));
1336 bool CodeGenModule::isInSanitizerBlacklist(llvm::Function *Fn,
1337 SourceLocation Loc) const {
1338 const auto &SanitizerBL = getContext().getSanitizerBlacklist();
1339 // Blacklist by function name.
1340 if (SanitizerBL.isBlacklistedFunction(Fn->getName()))
1342 // Blacklist by location.
1344 return SanitizerBL.isBlacklistedLocation(Loc);
1345 // If location is unknown, this may be a compiler-generated function. Assume
1346 // it's located in the main file.
1347 auto &SM = Context.getSourceManager();
1348 if (const auto *MainFile = SM.getFileEntryForID(SM.getMainFileID())) {
1349 return SanitizerBL.isBlacklistedFile(MainFile->getName());
1354 bool CodeGenModule::isInSanitizerBlacklist(llvm::GlobalVariable *GV,
1355 SourceLocation Loc, QualType Ty,
1356 StringRef Category) const {
1357 // For now globals can be blacklisted only in ASan and KASan.
1358 if (!LangOpts.Sanitize.hasOneOf(
1359 SanitizerKind::Address | SanitizerKind::KernelAddress))
1361 const auto &SanitizerBL = getContext().getSanitizerBlacklist();
1362 if (SanitizerBL.isBlacklistedGlobal(GV->getName(), Category))
1364 if (SanitizerBL.isBlacklistedLocation(Loc, Category))
1366 // Check global type.
1368 // Drill down the array types: if global variable of a fixed type is
1369 // blacklisted, we also don't instrument arrays of them.
1370 while (auto AT = dyn_cast<ArrayType>(Ty.getTypePtr()))
1371 Ty = AT->getElementType();
1372 Ty = Ty.getCanonicalType().getUnqualifiedType();
1373 // We allow to blacklist only record types (classes, structs etc.)
1374 if (Ty->isRecordType()) {
1375 std::string TypeStr = Ty.getAsString(getContext().getPrintingPolicy());
1376 if (SanitizerBL.isBlacklistedType(TypeStr, Category))
1383 bool CodeGenModule::MustBeEmitted(const ValueDecl *Global) {
1384 // Never defer when EmitAllDecls is specified.
1385 if (LangOpts.EmitAllDecls)
1388 return getContext().DeclMustBeEmitted(Global);
1391 bool CodeGenModule::MayBeEmittedEagerly(const ValueDecl *Global) {
1392 if (const auto *FD = dyn_cast<FunctionDecl>(Global))
1393 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1394 // Implicit template instantiations may change linkage if they are later
1395 // explicitly instantiated, so they should not be emitted eagerly.
1397 // If OpenMP is enabled and threadprivates must be generated like TLS, delay
1398 // codegen for global variables, because they may be marked as threadprivate.
1399 if (LangOpts.OpenMP && LangOpts.OpenMPUseTLS &&
1400 getContext().getTargetInfo().isTLSSupported() && isa<VarDecl>(Global))
1406 ConstantAddress CodeGenModule::GetAddrOfUuidDescriptor(
1407 const CXXUuidofExpr* E) {
1408 // Sema has verified that IIDSource has a __declspec(uuid()), and that its
1410 StringRef Uuid = E->getUuidAsStringRef(Context);
1411 std::string Name = "_GUID_" + Uuid.lower();
1412 std::replace(Name.begin(), Name.end(), '-', '_');
1414 // Contains a 32-bit field.
1415 CharUnits Alignment = CharUnits::fromQuantity(4);
1417 // Look for an existing global.
1418 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name))
1419 return ConstantAddress(GV, Alignment);
1421 llvm::Constant *Init = EmitUuidofInitializer(Uuid);
1422 assert(Init && "failed to initialize as constant");
1424 auto *GV = new llvm::GlobalVariable(
1425 getModule(), Init->getType(),
1426 /*isConstant=*/true, llvm::GlobalValue::LinkOnceODRLinkage, Init, Name);
1427 if (supportsCOMDAT())
1428 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
1429 return ConstantAddress(GV, Alignment);
1432 ConstantAddress CodeGenModule::GetWeakRefReference(const ValueDecl *VD) {
1433 const AliasAttr *AA = VD->getAttr<AliasAttr>();
1434 assert(AA && "No alias?");
1436 CharUnits Alignment = getContext().getDeclAlign(VD);
1437 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(VD->getType());
1439 // See if there is already something with the target's name in the module.
1440 llvm::GlobalValue *Entry = GetGlobalValue(AA->getAliasee());
1442 unsigned AS = getContext().getTargetAddressSpace(VD->getType());
1443 auto Ptr = llvm::ConstantExpr::getBitCast(Entry, DeclTy->getPointerTo(AS));
1444 return ConstantAddress(Ptr, Alignment);
1447 llvm::Constant *Aliasee;
1448 if (isa<llvm::FunctionType>(DeclTy))
1449 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy,
1450 GlobalDecl(cast<FunctionDecl>(VD)),
1451 /*ForVTable=*/false);
1453 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(),
1454 llvm::PointerType::getUnqual(DeclTy),
1457 auto *F = cast<llvm::GlobalValue>(Aliasee);
1458 F->setLinkage(llvm::Function::ExternalWeakLinkage);
1459 WeakRefReferences.insert(F);
1461 return ConstantAddress(Aliasee, Alignment);
1464 void CodeGenModule::EmitGlobal(GlobalDecl GD) {
1465 const auto *Global = cast<ValueDecl>(GD.getDecl());
1467 // Weak references don't produce any output by themselves.
1468 if (Global->hasAttr<WeakRefAttr>())
1471 // If this is an alias definition (which otherwise looks like a declaration)
1473 if (Global->hasAttr<AliasAttr>())
1474 return EmitAliasDefinition(GD);
1476 // If this is CUDA, be selective about which declarations we emit.
1477 if (LangOpts.CUDA) {
1478 if (LangOpts.CUDAIsDevice) {
1479 if (!Global->hasAttr<CUDADeviceAttr>() &&
1480 !Global->hasAttr<CUDAGlobalAttr>() &&
1481 !Global->hasAttr<CUDAConstantAttr>() &&
1482 !Global->hasAttr<CUDASharedAttr>())
1485 if (!Global->hasAttr<CUDAHostAttr>() && (
1486 Global->hasAttr<CUDADeviceAttr>() ||
1487 Global->hasAttr<CUDAConstantAttr>() ||
1488 Global->hasAttr<CUDASharedAttr>()))
1493 // Ignore declarations, they will be emitted on their first use.
1494 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) {
1495 // Forward declarations are emitted lazily on first use.
1496 if (!FD->doesThisDeclarationHaveABody()) {
1497 if (!FD->doesDeclarationForceExternallyVisibleDefinition())
1500 StringRef MangledName = getMangledName(GD);
1502 // Compute the function info and LLVM type.
1503 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
1504 llvm::Type *Ty = getTypes().GetFunctionType(FI);
1506 GetOrCreateLLVMFunction(MangledName, Ty, GD, /*ForVTable=*/false,
1507 /*DontDefer=*/false);
1511 const auto *VD = cast<VarDecl>(Global);
1512 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global.");
1514 if (VD->isThisDeclarationADefinition() != VarDecl::Definition &&
1515 !Context.isMSStaticDataMemberInlineDefinition(VD))
1519 // Defer code generation to first use when possible, e.g. if this is an inline
1520 // function. If the global must always be emitted, do it eagerly if possible
1521 // to benefit from cache locality.
1522 if (MustBeEmitted(Global) && MayBeEmittedEagerly(Global)) {
1523 // Emit the definition if it can't be deferred.
1524 EmitGlobalDefinition(GD);
1528 // If we're deferring emission of a C++ variable with an
1529 // initializer, remember the order in which it appeared in the file.
1530 if (getLangOpts().CPlusPlus && isa<VarDecl>(Global) &&
1531 cast<VarDecl>(Global)->hasInit()) {
1532 DelayedCXXInitPosition[Global] = CXXGlobalInits.size();
1533 CXXGlobalInits.push_back(nullptr);
1536 StringRef MangledName = getMangledName(GD);
1537 if (llvm::GlobalValue *GV = GetGlobalValue(MangledName)) {
1538 // The value has already been used and should therefore be emitted.
1539 addDeferredDeclToEmit(GV, GD);
1540 } else if (MustBeEmitted(Global)) {
1541 // The value must be emitted, but cannot be emitted eagerly.
1542 assert(!MayBeEmittedEagerly(Global));
1543 addDeferredDeclToEmit(/*GV=*/nullptr, GD);
1545 // Otherwise, remember that we saw a deferred decl with this name. The
1546 // first use of the mangled name will cause it to move into
1547 // DeferredDeclsToEmit.
1548 DeferredDecls[MangledName] = GD;
1553 struct FunctionIsDirectlyRecursive :
1554 public RecursiveASTVisitor<FunctionIsDirectlyRecursive> {
1555 const StringRef Name;
1556 const Builtin::Context &BI;
1558 FunctionIsDirectlyRecursive(StringRef N, const Builtin::Context &C) :
1559 Name(N), BI(C), Result(false) {
1561 typedef RecursiveASTVisitor<FunctionIsDirectlyRecursive> Base;
1563 bool TraverseCallExpr(CallExpr *E) {
1564 const FunctionDecl *FD = E->getDirectCallee();
1567 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>();
1568 if (Attr && Name == Attr->getLabel()) {
1572 unsigned BuiltinID = FD->getBuiltinID();
1573 if (!BuiltinID || !BI.isLibFunction(BuiltinID))
1575 StringRef BuiltinName = BI.getName(BuiltinID);
1576 if (BuiltinName.startswith("__builtin_") &&
1577 Name == BuiltinName.slice(strlen("__builtin_"), StringRef::npos)) {
1585 struct DLLImportFunctionVisitor
1586 : public RecursiveASTVisitor<DLLImportFunctionVisitor> {
1587 bool SafeToInline = true;
1589 bool VisitVarDecl(VarDecl *VD) {
1590 // A thread-local variable cannot be imported.
1591 SafeToInline = !VD->getTLSKind();
1592 return SafeToInline;
1595 // Make sure we're not referencing non-imported vars or functions.
1596 bool VisitDeclRefExpr(DeclRefExpr *E) {
1597 ValueDecl *VD = E->getDecl();
1598 if (isa<FunctionDecl>(VD))
1599 SafeToInline = VD->hasAttr<DLLImportAttr>();
1600 else if (VarDecl *V = dyn_cast<VarDecl>(VD))
1601 SafeToInline = !V->hasGlobalStorage() || V->hasAttr<DLLImportAttr>();
1602 return SafeToInline;
1604 bool VisitCXXDeleteExpr(CXXDeleteExpr *E) {
1605 SafeToInline = E->getOperatorDelete()->hasAttr<DLLImportAttr>();
1606 return SafeToInline;
1608 bool VisitCXXNewExpr(CXXNewExpr *E) {
1609 SafeToInline = E->getOperatorNew()->hasAttr<DLLImportAttr>();
1610 return SafeToInline;
1615 // isTriviallyRecursive - Check if this function calls another
1616 // decl that, because of the asm attribute or the other decl being a builtin,
1617 // ends up pointing to itself.
1619 CodeGenModule::isTriviallyRecursive(const FunctionDecl *FD) {
1621 if (getCXXABI().getMangleContext().shouldMangleDeclName(FD)) {
1622 // asm labels are a special kind of mangling we have to support.
1623 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>();
1626 Name = Attr->getLabel();
1628 Name = FD->getName();
1631 FunctionIsDirectlyRecursive Walker(Name, Context.BuiltinInfo);
1632 Walker.TraverseFunctionDecl(const_cast<FunctionDecl*>(FD));
1633 return Walker.Result;
1637 CodeGenModule::shouldEmitFunction(GlobalDecl GD) {
1638 if (getFunctionLinkage(GD) != llvm::Function::AvailableExternallyLinkage)
1640 const auto *F = cast<FunctionDecl>(GD.getDecl());
1641 if (CodeGenOpts.OptimizationLevel == 0 && !F->hasAttr<AlwaysInlineAttr>())
1644 if (F->hasAttr<DLLImportAttr>()) {
1645 // Check whether it would be safe to inline this dllimport function.
1646 DLLImportFunctionVisitor Visitor;
1647 Visitor.TraverseFunctionDecl(const_cast<FunctionDecl*>(F));
1648 if (!Visitor.SafeToInline)
1652 // PR9614. Avoid cases where the source code is lying to us. An available
1653 // externally function should have an equivalent function somewhere else,
1654 // but a function that calls itself is clearly not equivalent to the real
1656 // This happens in glibc's btowc and in some configure checks.
1657 return !isTriviallyRecursive(F);
1660 /// If the type for the method's class was generated by
1661 /// CGDebugInfo::createContextChain(), the cache contains only a
1662 /// limited DIType without any declarations. Since EmitFunctionStart()
1663 /// needs to find the canonical declaration for each method, we need
1664 /// to construct the complete type prior to emitting the method.
1665 void CodeGenModule::CompleteDIClassType(const CXXMethodDecl* D) {
1666 if (!D->isInstance())
1669 if (CGDebugInfo *DI = getModuleDebugInfo())
1670 if (getCodeGenOpts().getDebugInfo() >= CodeGenOptions::LimitedDebugInfo) {
1671 const auto *ThisPtr = cast<PointerType>(D->getThisType(getContext()));
1672 DI->getOrCreateRecordType(ThisPtr->getPointeeType(), D->getLocation());
1676 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD, llvm::GlobalValue *GV) {
1677 const auto *D = cast<ValueDecl>(GD.getDecl());
1679 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(),
1680 Context.getSourceManager(),
1681 "Generating code for declaration");
1683 if (isa<FunctionDecl>(D)) {
1684 // At -O0, don't generate IR for functions with available_externally
1686 if (!shouldEmitFunction(GD))
1689 if (const auto *Method = dyn_cast<CXXMethodDecl>(D)) {
1690 CompleteDIClassType(Method);
1691 // Make sure to emit the definition(s) before we emit the thunks.
1692 // This is necessary for the generation of certain thunks.
1693 if (const auto *CD = dyn_cast<CXXConstructorDecl>(Method))
1694 ABI->emitCXXStructor(CD, getFromCtorType(GD.getCtorType()));
1695 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(Method))
1696 ABI->emitCXXStructor(DD, getFromDtorType(GD.getDtorType()));
1698 EmitGlobalFunctionDefinition(GD, GV);
1700 if (Method->isVirtual())
1701 getVTables().EmitThunks(GD);
1706 return EmitGlobalFunctionDefinition(GD, GV);
1709 if (const auto *VD = dyn_cast<VarDecl>(D))
1710 return EmitGlobalVarDefinition(VD);
1712 llvm_unreachable("Invalid argument to EmitGlobalDefinition()");
1715 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old,
1716 llvm::Function *NewFn);
1718 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the
1719 /// module, create and return an llvm Function with the specified type. If there
1720 /// is something in the module with the specified name, return it potentially
1721 /// bitcasted to the right type.
1723 /// If D is non-null, it specifies a decl that correspond to this. This is used
1724 /// to set the attributes on the function when it is first created.
1726 CodeGenModule::GetOrCreateLLVMFunction(StringRef MangledName,
1728 GlobalDecl GD, bool ForVTable,
1729 bool DontDefer, bool IsThunk,
1730 llvm::AttributeSet ExtraAttrs,
1731 bool IsForDefinition) {
1732 const Decl *D = GD.getDecl();
1734 // Lookup the entry, lazily creating it if necessary.
1735 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
1737 if (WeakRefReferences.erase(Entry)) {
1738 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D);
1739 if (FD && !FD->hasAttr<WeakAttr>())
1740 Entry->setLinkage(llvm::Function::ExternalLinkage);
1743 // Handle dropped DLL attributes.
1744 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>())
1745 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
1747 // If there are two attempts to define the same mangled name, issue an
1749 if (IsForDefinition && !Entry->isDeclaration()) {
1751 // Check that GD is not yet in ExplicitDefinitions is required to make
1752 // sure that we issue an error only once.
1753 if (lookupRepresentativeDecl(MangledName, OtherGD) &&
1754 (GD.getCanonicalDecl().getDecl() !=
1755 OtherGD.getCanonicalDecl().getDecl()) &&
1756 DiagnosedConflictingDefinitions.insert(GD).second) {
1757 getDiags().Report(D->getLocation(),
1758 diag::err_duplicate_mangled_name);
1759 getDiags().Report(OtherGD.getDecl()->getLocation(),
1760 diag::note_previous_definition);
1764 if ((isa<llvm::Function>(Entry) || isa<llvm::GlobalAlias>(Entry)) &&
1765 (Entry->getType()->getElementType() == Ty)) {
1769 // Make sure the result is of the correct type.
1770 // (If function is requested for a definition, we always need to create a new
1771 // function, not just return a bitcast.)
1772 if (!IsForDefinition)
1773 return llvm::ConstantExpr::getBitCast(Entry, Ty->getPointerTo());
1776 // This function doesn't have a complete type (for example, the return
1777 // type is an incomplete struct). Use a fake type instead, and make
1778 // sure not to try to set attributes.
1779 bool IsIncompleteFunction = false;
1781 llvm::FunctionType *FTy;
1782 if (isa<llvm::FunctionType>(Ty)) {
1783 FTy = cast<llvm::FunctionType>(Ty);
1785 FTy = llvm::FunctionType::get(VoidTy, false);
1786 IsIncompleteFunction = true;
1790 llvm::Function::Create(FTy, llvm::Function::ExternalLinkage,
1791 Entry ? StringRef() : MangledName, &getModule());
1793 // If we already created a function with the same mangled name (but different
1794 // type) before, take its name and add it to the list of functions to be
1795 // replaced with F at the end of CodeGen.
1797 // This happens if there is a prototype for a function (e.g. "int f()") and
1798 // then a definition of a different type (e.g. "int f(int x)").
1802 // This might be an implementation of a function without a prototype, in
1803 // which case, try to do special replacement of calls which match the new
1804 // prototype. The really key thing here is that we also potentially drop
1805 // arguments from the call site so as to make a direct call, which makes the
1806 // inliner happier and suppresses a number of optimizer warnings (!) about
1807 // dropping arguments.
1808 if (!Entry->use_empty()) {
1809 ReplaceUsesOfNonProtoTypeWithRealFunction(Entry, F);
1810 Entry->removeDeadConstantUsers();
1813 llvm::Constant *BC = llvm::ConstantExpr::getBitCast(
1814 F, Entry->getType()->getElementType()->getPointerTo());
1815 addGlobalValReplacement(Entry, BC);
1818 assert(F->getName() == MangledName && "name was uniqued!");
1820 SetFunctionAttributes(GD, F, IsIncompleteFunction, IsThunk);
1821 if (ExtraAttrs.hasAttributes(llvm::AttributeSet::FunctionIndex)) {
1822 llvm::AttrBuilder B(ExtraAttrs, llvm::AttributeSet::FunctionIndex);
1823 F->addAttributes(llvm::AttributeSet::FunctionIndex,
1824 llvm::AttributeSet::get(VMContext,
1825 llvm::AttributeSet::FunctionIndex,
1830 // All MSVC dtors other than the base dtor are linkonce_odr and delegate to
1831 // each other bottoming out with the base dtor. Therefore we emit non-base
1832 // dtors on usage, even if there is no dtor definition in the TU.
1833 if (D && isa<CXXDestructorDecl>(D) &&
1834 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
1836 addDeferredDeclToEmit(F, GD);
1838 // This is the first use or definition of a mangled name. If there is a
1839 // deferred decl with this name, remember that we need to emit it at the end
1841 auto DDI = DeferredDecls.find(MangledName);
1842 if (DDI != DeferredDecls.end()) {
1843 // Move the potentially referenced deferred decl to the
1844 // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we
1845 // don't need it anymore).
1846 addDeferredDeclToEmit(F, DDI->second);
1847 DeferredDecls.erase(DDI);
1849 // Otherwise, there are cases we have to worry about where we're
1850 // using a declaration for which we must emit a definition but where
1851 // we might not find a top-level definition:
1852 // - member functions defined inline in their classes
1853 // - friend functions defined inline in some class
1854 // - special member functions with implicit definitions
1855 // If we ever change our AST traversal to walk into class methods,
1856 // this will be unnecessary.
1858 // We also don't emit a definition for a function if it's going to be an
1859 // entry in a vtable, unless it's already marked as used.
1860 } else if (getLangOpts().CPlusPlus && D) {
1861 // Look for a declaration that's lexically in a record.
1862 for (const auto *FD = cast<FunctionDecl>(D)->getMostRecentDecl(); FD;
1863 FD = FD->getPreviousDecl()) {
1864 if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) {
1865 if (FD->doesThisDeclarationHaveABody()) {
1866 addDeferredDeclToEmit(F, GD.getWithDecl(FD));
1874 // Make sure the result is of the requested type.
1875 if (!IsIncompleteFunction) {
1876 assert(F->getType()->getElementType() == Ty);
1880 llvm::Type *PTy = llvm::PointerType::getUnqual(Ty);
1881 return llvm::ConstantExpr::getBitCast(F, PTy);
1884 /// GetAddrOfFunction - Return the address of the given function. If Ty is
1885 /// non-null, then this function will use the specified type if it has to
1886 /// create it (this occurs when we see a definition of the function).
1887 llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD,
1891 bool IsForDefinition) {
1892 // If there was no specific requested type, just convert it now.
1894 const auto *FD = cast<FunctionDecl>(GD.getDecl());
1895 auto CanonTy = Context.getCanonicalType(FD->getType());
1896 Ty = getTypes().ConvertFunctionType(CanonTy, FD);
1899 StringRef MangledName = getMangledName(GD);
1900 return GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable, DontDefer,
1901 /*IsThunk=*/false, llvm::AttributeSet(),
1905 /// CreateRuntimeFunction - Create a new runtime function with the specified
1908 CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy,
1910 llvm::AttributeSet ExtraAttrs) {
1912 GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false,
1913 /*DontDefer=*/false, /*IsThunk=*/false, ExtraAttrs);
1914 if (auto *F = dyn_cast<llvm::Function>(C))
1916 F->setCallingConv(getRuntimeCC());
1920 /// CreateBuiltinFunction - Create a new builtin function with the specified
1923 CodeGenModule::CreateBuiltinFunction(llvm::FunctionType *FTy,
1925 llvm::AttributeSet ExtraAttrs) {
1927 GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false,
1928 /*DontDefer=*/false, /*IsThunk=*/false, ExtraAttrs);
1929 if (auto *F = dyn_cast<llvm::Function>(C))
1931 F->setCallingConv(getBuiltinCC());
1935 /// isTypeConstant - Determine whether an object of this type can be emitted
1938 /// If ExcludeCtor is true, the duration when the object's constructor runs
1939 /// will not be considered. The caller will need to verify that the object is
1940 /// not written to during its construction.
1941 bool CodeGenModule::isTypeConstant(QualType Ty, bool ExcludeCtor) {
1942 if (!Ty.isConstant(Context) && !Ty->isReferenceType())
1945 if (Context.getLangOpts().CPlusPlus) {
1946 if (const CXXRecordDecl *Record
1947 = Context.getBaseElementType(Ty)->getAsCXXRecordDecl())
1948 return ExcludeCtor && !Record->hasMutableFields() &&
1949 Record->hasTrivialDestructor();
1955 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module,
1956 /// create and return an llvm GlobalVariable with the specified type. If there
1957 /// is something in the module with the specified name, return it potentially
1958 /// bitcasted to the right type.
1960 /// If D is non-null, it specifies a decl that correspond to this. This is used
1961 /// to set the attributes on the global when it is first created.
1963 CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName,
1964 llvm::PointerType *Ty,
1966 // Lookup the entry, lazily creating it if necessary.
1967 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
1969 if (WeakRefReferences.erase(Entry)) {
1970 if (D && !D->hasAttr<WeakAttr>())
1971 Entry->setLinkage(llvm::Function::ExternalLinkage);
1974 // Handle dropped DLL attributes.
1975 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>())
1976 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
1978 if (Entry->getType() == Ty)
1981 // Make sure the result is of the correct type.
1982 if (Entry->getType()->getAddressSpace() != Ty->getAddressSpace())
1983 return llvm::ConstantExpr::getAddrSpaceCast(Entry, Ty);
1985 return llvm::ConstantExpr::getBitCast(Entry, Ty);
1988 unsigned AddrSpace = GetGlobalVarAddressSpace(D, Ty->getAddressSpace());
1989 auto *GV = new llvm::GlobalVariable(
1990 getModule(), Ty->getElementType(), false,
1991 llvm::GlobalValue::ExternalLinkage, nullptr, MangledName, nullptr,
1992 llvm::GlobalVariable::NotThreadLocal, AddrSpace);
1994 // This is the first use or definition of a mangled name. If there is a
1995 // deferred decl with this name, remember that we need to emit it at the end
1997 auto DDI = DeferredDecls.find(MangledName);
1998 if (DDI != DeferredDecls.end()) {
1999 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit
2000 // list, and remove it from DeferredDecls (since we don't need it anymore).
2001 addDeferredDeclToEmit(GV, DDI->second);
2002 DeferredDecls.erase(DDI);
2005 // Handle things which are present even on external declarations.
2007 // FIXME: This code is overly simple and should be merged with other global
2009 GV->setConstant(isTypeConstant(D->getType(), false));
2011 GV->setAlignment(getContext().getDeclAlign(D).getQuantity());
2013 setLinkageAndVisibilityForGV(GV, D);
2015 if (D->getTLSKind()) {
2016 if (D->getTLSKind() == VarDecl::TLS_Dynamic)
2017 CXXThreadLocals.push_back(D);
2021 // If required by the ABI, treat declarations of static data members with
2022 // inline initializers as definitions.
2023 if (getContext().isMSStaticDataMemberInlineDefinition(D)) {
2024 EmitGlobalVarDefinition(D);
2027 // Handle XCore specific ABI requirements.
2028 if (getTarget().getTriple().getArch() == llvm::Triple::xcore &&
2029 D->getLanguageLinkage() == CLanguageLinkage &&
2030 D->getType().isConstant(Context) &&
2031 isExternallyVisible(D->getLinkageAndVisibility().getLinkage()))
2032 GV->setSection(".cp.rodata");
2035 if (AddrSpace != Ty->getAddressSpace())
2036 return llvm::ConstantExpr::getAddrSpaceCast(GV, Ty);
2042 CodeGenModule::GetAddrOfGlobal(GlobalDecl GD,
2043 bool IsForDefinition) {
2044 if (isa<CXXConstructorDecl>(GD.getDecl()))
2045 return getAddrOfCXXStructor(cast<CXXConstructorDecl>(GD.getDecl()),
2046 getFromCtorType(GD.getCtorType()),
2047 /*FnInfo=*/nullptr, /*FnType=*/nullptr,
2048 /*DontDefer=*/false, IsForDefinition);
2049 else if (isa<CXXDestructorDecl>(GD.getDecl()))
2050 return getAddrOfCXXStructor(cast<CXXDestructorDecl>(GD.getDecl()),
2051 getFromDtorType(GD.getDtorType()),
2052 /*FnInfo=*/nullptr, /*FnType=*/nullptr,
2053 /*DontDefer=*/false, IsForDefinition);
2054 else if (isa<CXXMethodDecl>(GD.getDecl())) {
2055 auto FInfo = &getTypes().arrangeCXXMethodDeclaration(
2056 cast<CXXMethodDecl>(GD.getDecl()));
2057 auto Ty = getTypes().GetFunctionType(*FInfo);
2058 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false,
2060 } else if (isa<FunctionDecl>(GD.getDecl())) {
2061 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
2062 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
2063 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false,
2066 return GetAddrOfGlobalVar(cast<VarDecl>(GD.getDecl()));
2069 llvm::GlobalVariable *
2070 CodeGenModule::CreateOrReplaceCXXRuntimeVariable(StringRef Name,
2072 llvm::GlobalValue::LinkageTypes Linkage) {
2073 llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name);
2074 llvm::GlobalVariable *OldGV = nullptr;
2077 // Check if the variable has the right type.
2078 if (GV->getType()->getElementType() == Ty)
2081 // Because C++ name mangling, the only way we can end up with an already
2082 // existing global with the same name is if it has been declared extern "C".
2083 assert(GV->isDeclaration() && "Declaration has wrong type!");
2087 // Create a new variable.
2088 GV = new llvm::GlobalVariable(getModule(), Ty, /*isConstant=*/true,
2089 Linkage, nullptr, Name);
2092 // Replace occurrences of the old variable if needed.
2093 GV->takeName(OldGV);
2095 if (!OldGV->use_empty()) {
2096 llvm::Constant *NewPtrForOldDecl =
2097 llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
2098 OldGV->replaceAllUsesWith(NewPtrForOldDecl);
2101 OldGV->eraseFromParent();
2104 if (supportsCOMDAT() && GV->isWeakForLinker() &&
2105 !GV->hasAvailableExternallyLinkage())
2106 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
2111 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the
2112 /// given global variable. If Ty is non-null and if the global doesn't exist,
2113 /// then it will be created with the specified type instead of whatever the
2114 /// normal requested type would be.
2115 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D,
2117 assert(D->hasGlobalStorage() && "Not a global variable");
2118 QualType ASTTy = D->getType();
2120 Ty = getTypes().ConvertTypeForMem(ASTTy);
2122 llvm::PointerType *PTy =
2123 llvm::PointerType::get(Ty, getContext().getTargetAddressSpace(ASTTy));
2125 StringRef MangledName = getMangledName(D);
2126 return GetOrCreateLLVMGlobal(MangledName, PTy, D);
2129 /// CreateRuntimeVariable - Create a new runtime global variable with the
2130 /// specified type and name.
2132 CodeGenModule::CreateRuntimeVariable(llvm::Type *Ty,
2134 return GetOrCreateLLVMGlobal(Name, llvm::PointerType::getUnqual(Ty), nullptr);
2137 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) {
2138 assert(!D->getInit() && "Cannot emit definite definitions here!");
2140 if (!MustBeEmitted(D)) {
2141 // If we have not seen a reference to this variable yet, place it
2142 // into the deferred declarations table to be emitted if needed
2144 StringRef MangledName = getMangledName(D);
2145 if (!GetGlobalValue(MangledName)) {
2146 DeferredDecls[MangledName] = D;
2151 // The tentative definition is the only definition.
2152 EmitGlobalVarDefinition(D);
2155 CharUnits CodeGenModule::GetTargetTypeStoreSize(llvm::Type *Ty) const {
2156 return Context.toCharUnitsFromBits(
2157 getDataLayout().getTypeStoreSizeInBits(Ty));
2160 unsigned CodeGenModule::GetGlobalVarAddressSpace(const VarDecl *D,
2161 unsigned AddrSpace) {
2162 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) {
2163 if (D->hasAttr<CUDAConstantAttr>())
2164 AddrSpace = getContext().getTargetAddressSpace(LangAS::cuda_constant);
2165 else if (D->hasAttr<CUDASharedAttr>())
2166 AddrSpace = getContext().getTargetAddressSpace(LangAS::cuda_shared);
2168 AddrSpace = getContext().getTargetAddressSpace(LangAS::cuda_device);
2174 template<typename SomeDecl>
2175 void CodeGenModule::MaybeHandleStaticInExternC(const SomeDecl *D,
2176 llvm::GlobalValue *GV) {
2177 if (!getLangOpts().CPlusPlus)
2180 // Must have 'used' attribute, or else inline assembly can't rely on
2181 // the name existing.
2182 if (!D->template hasAttr<UsedAttr>())
2185 // Must have internal linkage and an ordinary name.
2186 if (!D->getIdentifier() || D->getFormalLinkage() != InternalLinkage)
2189 // Must be in an extern "C" context. Entities declared directly within
2190 // a record are not extern "C" even if the record is in such a context.
2191 const SomeDecl *First = D->getFirstDecl();
2192 if (First->getDeclContext()->isRecord() || !First->isInExternCContext())
2195 // OK, this is an internal linkage entity inside an extern "C" linkage
2196 // specification. Make a note of that so we can give it the "expected"
2197 // mangled name if nothing else is using that name.
2198 std::pair<StaticExternCMap::iterator, bool> R =
2199 StaticExternCValues.insert(std::make_pair(D->getIdentifier(), GV));
2201 // If we have multiple internal linkage entities with the same name
2202 // in extern "C" regions, none of them gets that name.
2204 R.first->second = nullptr;
2207 static bool shouldBeInCOMDAT(CodeGenModule &CGM, const Decl &D) {
2208 if (!CGM.supportsCOMDAT())
2211 if (D.hasAttr<SelectAnyAttr>())
2215 if (auto *VD = dyn_cast<VarDecl>(&D))
2216 Linkage = CGM.getContext().GetGVALinkageForVariable(VD);
2218 Linkage = CGM.getContext().GetGVALinkageForFunction(cast<FunctionDecl>(&D));
2222 case GVA_AvailableExternally:
2223 case GVA_StrongExternal:
2225 case GVA_DiscardableODR:
2229 llvm_unreachable("No such linkage");
2232 void CodeGenModule::maybeSetTrivialComdat(const Decl &D,
2233 llvm::GlobalObject &GO) {
2234 if (!shouldBeInCOMDAT(*this, D))
2236 GO.setComdat(TheModule.getOrInsertComdat(GO.getName()));
2239 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D) {
2240 llvm::Constant *Init = nullptr;
2241 QualType ASTTy = D->getType();
2242 CXXRecordDecl *RD = ASTTy->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
2243 bool NeedsGlobalCtor = false;
2244 bool NeedsGlobalDtor = RD && !RD->hasTrivialDestructor();
2246 const VarDecl *InitDecl;
2247 const Expr *InitExpr = D->getAnyInitializer(InitDecl);
2249 // CUDA E.2.4.1 "__shared__ variables cannot have an initialization as part
2250 // of their declaration."
2251 if (getLangOpts().CPlusPlus && getLangOpts().CUDAIsDevice
2252 && D->hasAttr<CUDASharedAttr>()) {
2254 const auto *C = dyn_cast<CXXConstructExpr>(InitExpr);
2255 if (C == nullptr || !C->getConstructor()->hasTrivialBody())
2256 Error(D->getLocation(),
2257 "__shared__ variable cannot have an initialization.");
2259 Init = llvm::UndefValue::get(getTypes().ConvertType(ASTTy));
2260 } else if (!InitExpr) {
2261 // This is a tentative definition; tentative definitions are
2262 // implicitly initialized with { 0 }.
2264 // Note that tentative definitions are only emitted at the end of
2265 // a translation unit, so they should never have incomplete
2266 // type. In addition, EmitTentativeDefinition makes sure that we
2267 // never attempt to emit a tentative definition if a real one
2268 // exists. A use may still exists, however, so we still may need
2270 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type");
2271 Init = EmitNullConstant(D->getType());
2273 initializedGlobalDecl = GlobalDecl(D);
2274 Init = EmitConstantInit(*InitDecl);
2277 QualType T = InitExpr->getType();
2278 if (D->getType()->isReferenceType())
2281 if (getLangOpts().CPlusPlus) {
2282 Init = EmitNullConstant(T);
2283 NeedsGlobalCtor = true;
2285 ErrorUnsupported(D, "static initializer");
2286 Init = llvm::UndefValue::get(getTypes().ConvertType(T));
2289 // We don't need an initializer, so remove the entry for the delayed
2290 // initializer position (just in case this entry was delayed) if we
2291 // also don't need to register a destructor.
2292 if (getLangOpts().CPlusPlus && !NeedsGlobalDtor)
2293 DelayedCXXInitPosition.erase(D);
2297 llvm::Type* InitType = Init->getType();
2298 llvm::Constant *Entry = GetAddrOfGlobalVar(D, InitType);
2300 // Strip off a bitcast if we got one back.
2301 if (auto *CE = dyn_cast<llvm::ConstantExpr>(Entry)) {
2302 assert(CE->getOpcode() == llvm::Instruction::BitCast ||
2303 CE->getOpcode() == llvm::Instruction::AddrSpaceCast ||
2304 // All zero index gep.
2305 CE->getOpcode() == llvm::Instruction::GetElementPtr);
2306 Entry = CE->getOperand(0);
2309 // Entry is now either a Function or GlobalVariable.
2310 auto *GV = dyn_cast<llvm::GlobalVariable>(Entry);
2312 // We have a definition after a declaration with the wrong type.
2313 // We must make a new GlobalVariable* and update everything that used OldGV
2314 // (a declaration or tentative definition) with the new GlobalVariable*
2315 // (which will be a definition).
2317 // This happens if there is a prototype for a global (e.g.
2318 // "extern int x[];") and then a definition of a different type (e.g.
2319 // "int x[10];"). This also happens when an initializer has a different type
2320 // from the type of the global (this happens with unions).
2322 GV->getType()->getElementType() != InitType ||
2323 GV->getType()->getAddressSpace() !=
2324 GetGlobalVarAddressSpace(D, getContext().getTargetAddressSpace(ASTTy))) {
2326 // Move the old entry aside so that we'll create a new one.
2327 Entry->setName(StringRef());
2329 // Make a new global with the correct type, this is now guaranteed to work.
2330 GV = cast<llvm::GlobalVariable>(GetAddrOfGlobalVar(D, InitType));
2332 // Replace all uses of the old global with the new global
2333 llvm::Constant *NewPtrForOldDecl =
2334 llvm::ConstantExpr::getBitCast(GV, Entry->getType());
2335 Entry->replaceAllUsesWith(NewPtrForOldDecl);
2337 // Erase the old global, since it is no longer used.
2338 cast<llvm::GlobalValue>(Entry)->eraseFromParent();
2341 MaybeHandleStaticInExternC(D, GV);
2343 if (D->hasAttr<AnnotateAttr>())
2344 AddGlobalAnnotations(D, GV);
2346 // CUDA B.2.1 "The __device__ qualifier declares a variable that resides on
2347 // the device. [...]"
2348 // CUDA B.2.2 "The __constant__ qualifier, optionally used together with
2349 // __device__, declares a variable that: [...]
2350 // Is accessible from all the threads within the grid and from the host
2351 // through the runtime library (cudaGetSymbolAddress() / cudaGetSymbolSize()
2352 // / cudaMemcpyToSymbol() / cudaMemcpyFromSymbol())."
2353 if (GV && LangOpts.CUDA && LangOpts.CUDAIsDevice &&
2354 (D->hasAttr<CUDAConstantAttr>() || D->hasAttr<CUDADeviceAttr>())) {
2355 GV->setExternallyInitialized(true);
2357 GV->setInitializer(Init);
2359 // If it is safe to mark the global 'constant', do so now.
2360 GV->setConstant(!NeedsGlobalCtor && !NeedsGlobalDtor &&
2361 isTypeConstant(D->getType(), true));
2363 // If it is in a read-only section, mark it 'constant'.
2364 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) {
2365 const ASTContext::SectionInfo &SI = Context.SectionInfos[SA->getName()];
2366 if ((SI.SectionFlags & ASTContext::PSF_Write) == 0)
2367 GV->setConstant(true);
2370 GV->setAlignment(getContext().getDeclAlign(D).getQuantity());
2372 // Set the llvm linkage type as appropriate.
2373 llvm::GlobalValue::LinkageTypes Linkage =
2374 getLLVMLinkageVarDefinition(D, GV->isConstant());
2376 // On Darwin, if the normal linkage of a C++ thread_local variable is
2377 // LinkOnce or Weak, we keep the normal linkage to prevent multiple
2378 // copies within a linkage unit; otherwise, the backing variable has
2379 // internal linkage and all accesses should just be calls to the
2380 // Itanium-specified entry point, which has the normal linkage of the
2381 // variable. This is to preserve the ability to change the implementation
2382 // behind the scenes.
2383 if (!D->isStaticLocal() && D->getTLSKind() == VarDecl::TLS_Dynamic &&
2384 Context.getTargetInfo().getTriple().isOSDarwin() &&
2385 !llvm::GlobalVariable::isLinkOnceLinkage(Linkage) &&
2386 !llvm::GlobalVariable::isWeakLinkage(Linkage))
2387 Linkage = llvm::GlobalValue::InternalLinkage;
2389 GV->setLinkage(Linkage);
2390 if (D->hasAttr<DLLImportAttr>())
2391 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
2392 else if (D->hasAttr<DLLExportAttr>())
2393 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
2395 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass);
2397 if (Linkage == llvm::GlobalVariable::CommonLinkage)
2398 // common vars aren't constant even if declared const.
2399 GV->setConstant(false);
2401 setNonAliasAttributes(D, GV);
2403 if (D->getTLSKind() && !GV->isThreadLocal()) {
2404 if (D->getTLSKind() == VarDecl::TLS_Dynamic)
2405 CXXThreadLocals.push_back(D);
2409 maybeSetTrivialComdat(*D, *GV);
2411 // Emit the initializer function if necessary.
2412 if (NeedsGlobalCtor || NeedsGlobalDtor)
2413 EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor);
2415 SanitizerMD->reportGlobalToASan(GV, *D, NeedsGlobalCtor);
2417 // Emit global variable debug information.
2418 if (CGDebugInfo *DI = getModuleDebugInfo())
2419 if (getCodeGenOpts().getDebugInfo() >= CodeGenOptions::LimitedDebugInfo)
2420 DI->EmitGlobalVariable(GV, D);
2423 static bool isVarDeclStrongDefinition(const ASTContext &Context,
2424 CodeGenModule &CGM, const VarDecl *D,
2426 // Don't give variables common linkage if -fno-common was specified unless it
2427 // was overridden by a NoCommon attribute.
2428 if ((NoCommon || D->hasAttr<NoCommonAttr>()) && !D->hasAttr<CommonAttr>())
2432 // A declaration of an identifier for an object that has file scope without
2433 // an initializer, and without a storage-class specifier or with the
2434 // storage-class specifier static, constitutes a tentative definition.
2435 if (D->getInit() || D->hasExternalStorage())
2438 // A variable cannot be both common and exist in a section.
2439 if (D->hasAttr<SectionAttr>())
2442 // Thread local vars aren't considered common linkage.
2443 if (D->getTLSKind())
2446 // Tentative definitions marked with WeakImportAttr are true definitions.
2447 if (D->hasAttr<WeakImportAttr>())
2450 // A variable cannot be both common and exist in a comdat.
2451 if (shouldBeInCOMDAT(CGM, *D))
2454 // Declarations with a required alignment do not have common linakge in MSVC
2456 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2457 if (D->hasAttr<AlignedAttr>())
2459 QualType VarType = D->getType();
2460 if (Context.isAlignmentRequired(VarType))
2463 if (const auto *RT = VarType->getAs<RecordType>()) {
2464 const RecordDecl *RD = RT->getDecl();
2465 for (const FieldDecl *FD : RD->fields()) {
2466 if (FD->isBitField())
2468 if (FD->hasAttr<AlignedAttr>())
2470 if (Context.isAlignmentRequired(FD->getType()))
2479 llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageForDeclarator(
2480 const DeclaratorDecl *D, GVALinkage Linkage, bool IsConstantVariable) {
2481 if (Linkage == GVA_Internal)
2482 return llvm::Function::InternalLinkage;
2484 if (D->hasAttr<WeakAttr>()) {
2485 if (IsConstantVariable)
2486 return llvm::GlobalVariable::WeakODRLinkage;
2488 return llvm::GlobalVariable::WeakAnyLinkage;
2491 // We are guaranteed to have a strong definition somewhere else,
2492 // so we can use available_externally linkage.
2493 if (Linkage == GVA_AvailableExternally)
2494 return llvm::Function::AvailableExternallyLinkage;
2496 // Note that Apple's kernel linker doesn't support symbol
2497 // coalescing, so we need to avoid linkonce and weak linkages there.
2498 // Normally, this means we just map to internal, but for explicit
2499 // instantiations we'll map to external.
2501 // In C++, the compiler has to emit a definition in every translation unit
2502 // that references the function. We should use linkonce_odr because
2503 // a) if all references in this translation unit are optimized away, we
2504 // don't need to codegen it. b) if the function persists, it needs to be
2505 // merged with other definitions. c) C++ has the ODR, so we know the
2506 // definition is dependable.
2507 if (Linkage == GVA_DiscardableODR)
2508 return !Context.getLangOpts().AppleKext ? llvm::Function::LinkOnceODRLinkage
2509 : llvm::Function::InternalLinkage;
2511 // An explicit instantiation of a template has weak linkage, since
2512 // explicit instantiations can occur in multiple translation units
2513 // and must all be equivalent. However, we are not allowed to
2514 // throw away these explicit instantiations.
2515 if (Linkage == GVA_StrongODR)
2516 return !Context.getLangOpts().AppleKext ? llvm::Function::WeakODRLinkage
2517 : llvm::Function::ExternalLinkage;
2519 // C++ doesn't have tentative definitions and thus cannot have common
2521 if (!getLangOpts().CPlusPlus && isa<VarDecl>(D) &&
2522 !isVarDeclStrongDefinition(Context, *this, cast<VarDecl>(D),
2523 CodeGenOpts.NoCommon))
2524 return llvm::GlobalVariable::CommonLinkage;
2526 // selectany symbols are externally visible, so use weak instead of
2527 // linkonce. MSVC optimizes away references to const selectany globals, so
2528 // all definitions should be the same and ODR linkage should be used.
2529 // http://msdn.microsoft.com/en-us/library/5tkz6s71.aspx
2530 if (D->hasAttr<SelectAnyAttr>())
2531 return llvm::GlobalVariable::WeakODRLinkage;
2533 // Otherwise, we have strong external linkage.
2534 assert(Linkage == GVA_StrongExternal);
2535 return llvm::GlobalVariable::ExternalLinkage;
2538 llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageVarDefinition(
2539 const VarDecl *VD, bool IsConstant) {
2540 GVALinkage Linkage = getContext().GetGVALinkageForVariable(VD);
2541 return getLLVMLinkageForDeclarator(VD, Linkage, IsConstant);
2544 /// Replace the uses of a function that was declared with a non-proto type.
2545 /// We want to silently drop extra arguments from call sites
2546 static void replaceUsesOfNonProtoConstant(llvm::Constant *old,
2547 llvm::Function *newFn) {
2549 if (old->use_empty()) return;
2551 llvm::Type *newRetTy = newFn->getReturnType();
2552 SmallVector<llvm::Value*, 4> newArgs;
2553 SmallVector<llvm::OperandBundleDef, 1> newBundles;
2555 for (llvm::Value::use_iterator ui = old->use_begin(), ue = old->use_end();
2557 llvm::Value::use_iterator use = ui++; // Increment before the use is erased.
2558 llvm::User *user = use->getUser();
2560 // Recognize and replace uses of bitcasts. Most calls to
2561 // unprototyped functions will use bitcasts.
2562 if (auto *bitcast = dyn_cast<llvm::ConstantExpr>(user)) {
2563 if (bitcast->getOpcode() == llvm::Instruction::BitCast)
2564 replaceUsesOfNonProtoConstant(bitcast, newFn);
2568 // Recognize calls to the function.
2569 llvm::CallSite callSite(user);
2570 if (!callSite) continue;
2571 if (!callSite.isCallee(&*use)) continue;
2573 // If the return types don't match exactly, then we can't
2574 // transform this call unless it's dead.
2575 if (callSite->getType() != newRetTy && !callSite->use_empty())
2578 // Get the call site's attribute list.
2579 SmallVector<llvm::AttributeSet, 8> newAttrs;
2580 llvm::AttributeSet oldAttrs = callSite.getAttributes();
2582 // Collect any return attributes from the call.
2583 if (oldAttrs.hasAttributes(llvm::AttributeSet::ReturnIndex))
2585 llvm::AttributeSet::get(newFn->getContext(),
2586 oldAttrs.getRetAttributes()));
2588 // If the function was passed too few arguments, don't transform.
2589 unsigned newNumArgs = newFn->arg_size();
2590 if (callSite.arg_size() < newNumArgs) continue;
2592 // If extra arguments were passed, we silently drop them.
2593 // If any of the types mismatch, we don't transform.
2595 bool dontTransform = false;
2596 for (llvm::Function::arg_iterator ai = newFn->arg_begin(),
2597 ae = newFn->arg_end(); ai != ae; ++ai, ++argNo) {
2598 if (callSite.getArgument(argNo)->getType() != ai->getType()) {
2599 dontTransform = true;
2603 // Add any parameter attributes.
2604 if (oldAttrs.hasAttributes(argNo + 1))
2607 AttributeSet::get(newFn->getContext(),
2608 oldAttrs.getParamAttributes(argNo + 1)));
2613 if (oldAttrs.hasAttributes(llvm::AttributeSet::FunctionIndex))
2614 newAttrs.push_back(llvm::AttributeSet::get(newFn->getContext(),
2615 oldAttrs.getFnAttributes()));
2617 // Okay, we can transform this. Create the new call instruction and copy
2618 // over the required information.
2619 newArgs.append(callSite.arg_begin(), callSite.arg_begin() + argNo);
2621 // Copy over any operand bundles.
2622 callSite.getOperandBundlesAsDefs(newBundles);
2624 llvm::CallSite newCall;
2625 if (callSite.isCall()) {
2626 newCall = llvm::CallInst::Create(newFn, newArgs, newBundles, "",
2627 callSite.getInstruction());
2629 auto *oldInvoke = cast<llvm::InvokeInst>(callSite.getInstruction());
2630 newCall = llvm::InvokeInst::Create(newFn,
2631 oldInvoke->getNormalDest(),
2632 oldInvoke->getUnwindDest(),
2633 newArgs, newBundles, "",
2634 callSite.getInstruction());
2636 newArgs.clear(); // for the next iteration
2638 if (!newCall->getType()->isVoidTy())
2639 newCall->takeName(callSite.getInstruction());
2640 newCall.setAttributes(
2641 llvm::AttributeSet::get(newFn->getContext(), newAttrs));
2642 newCall.setCallingConv(callSite.getCallingConv());
2644 // Finally, remove the old call, replacing any uses with the new one.
2645 if (!callSite->use_empty())
2646 callSite->replaceAllUsesWith(newCall.getInstruction());
2648 // Copy debug location attached to CI.
2649 if (callSite->getDebugLoc())
2650 newCall->setDebugLoc(callSite->getDebugLoc());
2652 callSite->eraseFromParent();
2656 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we
2657 /// implement a function with no prototype, e.g. "int foo() {}". If there are
2658 /// existing call uses of the old function in the module, this adjusts them to
2659 /// call the new function directly.
2661 /// This is not just a cleanup: the always_inline pass requires direct calls to
2662 /// functions to be able to inline them. If there is a bitcast in the way, it
2663 /// won't inline them. Instcombine normally deletes these calls, but it isn't
2665 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old,
2666 llvm::Function *NewFn) {
2667 // If we're redefining a global as a function, don't transform it.
2668 if (!isa<llvm::Function>(Old)) return;
2670 replaceUsesOfNonProtoConstant(Old, NewFn);
2673 void CodeGenModule::HandleCXXStaticMemberVarInstantiation(VarDecl *VD) {
2674 TemplateSpecializationKind TSK = VD->getTemplateSpecializationKind();
2675 // If we have a definition, this might be a deferred decl. If the
2676 // instantiation is explicit, make sure we emit it at the end.
2677 if (VD->getDefinition() && TSK == TSK_ExplicitInstantiationDefinition)
2678 GetAddrOfGlobalVar(VD);
2680 EmitTopLevelDecl(VD);
2683 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD,
2684 llvm::GlobalValue *GV) {
2685 const auto *D = cast<FunctionDecl>(GD.getDecl());
2687 // Compute the function info and LLVM type.
2688 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
2689 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
2691 // Get or create the prototype for the function.
2692 if (!GV || (GV->getType()->getElementType() != Ty))
2693 GV = cast<llvm::GlobalValue>(GetAddrOfFunction(GD, Ty, /*ForVTable=*/false,
2695 /*IsForDefinition=*/true));
2698 if (!GV->isDeclaration())
2701 // We need to set linkage and visibility on the function before
2702 // generating code for it because various parts of IR generation
2703 // want to propagate this information down (e.g. to local static
2705 auto *Fn = cast<llvm::Function>(GV);
2706 setFunctionLinkage(GD, Fn);
2707 setFunctionDLLStorageClass(GD, Fn);
2709 // FIXME: this is redundant with part of setFunctionDefinitionAttributes
2710 setGlobalVisibility(Fn, D);
2712 MaybeHandleStaticInExternC(D, Fn);
2714 maybeSetTrivialComdat(*D, *Fn);
2716 CodeGenFunction(*this).GenerateCode(D, Fn, FI);
2718 setFunctionDefinitionAttributes(D, Fn);
2719 SetLLVMFunctionAttributesForDefinition(D, Fn);
2721 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>())
2722 AddGlobalCtor(Fn, CA->getPriority());
2723 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>())
2724 AddGlobalDtor(Fn, DA->getPriority());
2725 if (D->hasAttr<AnnotateAttr>())
2726 AddGlobalAnnotations(D, Fn);
2729 void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) {
2730 const auto *D = cast<ValueDecl>(GD.getDecl());
2731 const AliasAttr *AA = D->getAttr<AliasAttr>();
2732 assert(AA && "Not an alias?");
2734 StringRef MangledName = getMangledName(GD);
2736 if (AA->getAliasee() == MangledName) {
2737 Diags.Report(AA->getLocation(), diag::err_cyclic_alias);
2741 // If there is a definition in the module, then it wins over the alias.
2742 // This is dubious, but allow it to be safe. Just ignore the alias.
2743 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
2744 if (Entry && !Entry->isDeclaration())
2747 Aliases.push_back(GD);
2749 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType());
2751 // Create a reference to the named value. This ensures that it is emitted
2752 // if a deferred decl.
2753 llvm::Constant *Aliasee;
2754 if (isa<llvm::FunctionType>(DeclTy))
2755 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GD,
2756 /*ForVTable=*/false);
2758 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(),
2759 llvm::PointerType::getUnqual(DeclTy),
2762 // Create the new alias itself, but don't set a name yet.
2763 auto *GA = llvm::GlobalAlias::create(
2764 DeclTy, 0, llvm::Function::ExternalLinkage, "", Aliasee, &getModule());
2767 if (GA->getAliasee() == Entry) {
2768 Diags.Report(AA->getLocation(), diag::err_cyclic_alias);
2772 assert(Entry->isDeclaration());
2774 // If there is a declaration in the module, then we had an extern followed
2775 // by the alias, as in:
2776 // extern int test6();
2778 // int test6() __attribute__((alias("test7")));
2780 // Remove it and replace uses of it with the alias.
2781 GA->takeName(Entry);
2783 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA,
2785 Entry->eraseFromParent();
2787 GA->setName(MangledName);
2790 // Set attributes which are particular to an alias; this is a
2791 // specialization of the attributes which may be set on a global
2792 // variable/function.
2793 if (D->hasAttr<WeakAttr>() || D->hasAttr<WeakRefAttr>() ||
2794 D->isWeakImported()) {
2795 GA->setLinkage(llvm::Function::WeakAnyLinkage);
2798 if (const auto *VD = dyn_cast<VarDecl>(D))
2799 if (VD->getTLSKind())
2800 setTLSMode(GA, *VD);
2802 setAliasAttributes(D, GA);
2805 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID,
2806 ArrayRef<llvm::Type*> Tys) {
2807 return llvm::Intrinsic::getDeclaration(&getModule(), (llvm::Intrinsic::ID)IID,
2811 static llvm::StringMapEntry<llvm::GlobalVariable *> &
2812 GetConstantCFStringEntry(llvm::StringMap<llvm::GlobalVariable *> &Map,
2813 const StringLiteral *Literal, bool TargetIsLSB,
2814 bool &IsUTF16, unsigned &StringLength) {
2815 StringRef String = Literal->getString();
2816 unsigned NumBytes = String.size();
2818 // Check for simple case.
2819 if (!Literal->containsNonAsciiOrNull()) {
2820 StringLength = NumBytes;
2821 return *Map.insert(std::make_pair(String, nullptr)).first;
2824 // Otherwise, convert the UTF8 literals into a string of shorts.
2827 SmallVector<UTF16, 128> ToBuf(NumBytes + 1); // +1 for ending nulls.
2828 const UTF8 *FromPtr = (const UTF8 *)String.data();
2829 UTF16 *ToPtr = &ToBuf[0];
2831 (void)ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes,
2832 &ToPtr, ToPtr + NumBytes,
2835 // ConvertUTF8toUTF16 returns the length in ToPtr.
2836 StringLength = ToPtr - &ToBuf[0];
2838 // Add an explicit null.
2840 return *Map.insert(std::make_pair(
2841 StringRef(reinterpret_cast<const char *>(ToBuf.data()),
2842 (StringLength + 1) * 2),
2846 static llvm::StringMapEntry<llvm::GlobalVariable *> &
2847 GetConstantStringEntry(llvm::StringMap<llvm::GlobalVariable *> &Map,
2848 const StringLiteral *Literal, unsigned &StringLength) {
2849 StringRef String = Literal->getString();
2850 StringLength = String.size();
2851 return *Map.insert(std::make_pair(String, nullptr)).first;
2855 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) {
2856 unsigned StringLength = 0;
2857 bool isUTF16 = false;
2858 llvm::StringMapEntry<llvm::GlobalVariable *> &Entry =
2859 GetConstantCFStringEntry(CFConstantStringMap, Literal,
2860 getDataLayout().isLittleEndian(), isUTF16,
2863 if (auto *C = Entry.second)
2864 return ConstantAddress(C, CharUnits::fromQuantity(C->getAlignment()));
2866 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty);
2867 llvm::Constant *Zeros[] = { Zero, Zero };
2870 // If we don't already have it, get __CFConstantStringClassReference.
2871 if (!CFConstantStringClassRef) {
2872 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy);
2873 Ty = llvm::ArrayType::get(Ty, 0);
2874 llvm::Constant *GV = CreateRuntimeVariable(Ty,
2875 "__CFConstantStringClassReference");
2876 // Decay array -> ptr
2877 V = llvm::ConstantExpr::getGetElementPtr(Ty, GV, Zeros);
2878 CFConstantStringClassRef = V;
2881 V = CFConstantStringClassRef;
2883 QualType CFTy = getContext().getCFConstantStringType();
2885 auto *STy = cast<llvm::StructType>(getTypes().ConvertType(CFTy));
2887 llvm::Constant *Fields[4];
2890 Fields[0] = cast<llvm::ConstantExpr>(V);
2893 llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy);
2894 Fields[1] = isUTF16 ? llvm::ConstantInt::get(Ty, 0x07d0) :
2895 llvm::ConstantInt::get(Ty, 0x07C8);
2898 llvm::Constant *C = nullptr;
2900 auto Arr = llvm::makeArrayRef(
2901 reinterpret_cast<uint16_t *>(const_cast<char *>(Entry.first().data())),
2902 Entry.first().size() / 2);
2903 C = llvm::ConstantDataArray::get(VMContext, Arr);
2905 C = llvm::ConstantDataArray::getString(VMContext, Entry.first());
2908 // Note: -fwritable-strings doesn't make the backing store strings of
2909 // CFStrings writable. (See <rdar://problem/10657500>)
2911 new llvm::GlobalVariable(getModule(), C->getType(), /*isConstant=*/true,
2912 llvm::GlobalValue::PrivateLinkage, C, ".str");
2913 GV->setUnnamedAddr(true);
2914 // Don't enforce the target's minimum global alignment, since the only use
2915 // of the string is via this class initializer.
2916 // FIXME: We set the section explicitly to avoid a bug in ld64 224.1. Without
2917 // it LLVM can merge the string with a non unnamed_addr one during LTO. Doing
2918 // that changes the section it ends in, which surprises ld64.
2920 CharUnits Align = getContext().getTypeAlignInChars(getContext().ShortTy);
2921 GV->setAlignment(Align.getQuantity());
2922 GV->setSection("__TEXT,__ustring");
2924 CharUnits Align = getContext().getTypeAlignInChars(getContext().CharTy);
2925 GV->setAlignment(Align.getQuantity());
2926 GV->setSection("__TEXT,__cstring,cstring_literals");
2931 llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV, Zeros);
2934 // Cast the UTF16 string to the correct type.
2935 Fields[2] = llvm::ConstantExpr::getBitCast(Fields[2], Int8PtrTy);
2938 Ty = getTypes().ConvertType(getContext().LongTy);
2939 Fields[3] = llvm::ConstantInt::get(Ty, StringLength);
2941 CharUnits Alignment = getPointerAlign();
2944 C = llvm::ConstantStruct::get(STy, Fields);
2945 GV = new llvm::GlobalVariable(getModule(), C->getType(), true,
2946 llvm::GlobalVariable::PrivateLinkage, C,
2947 "_unnamed_cfstring_");
2948 GV->setSection("__DATA,__cfstring");
2949 GV->setAlignment(Alignment.getQuantity());
2952 return ConstantAddress(GV, Alignment);
2956 CodeGenModule::GetAddrOfConstantString(const StringLiteral *Literal) {
2957 unsigned StringLength = 0;
2958 llvm::StringMapEntry<llvm::GlobalVariable *> &Entry =
2959 GetConstantStringEntry(CFConstantStringMap, Literal, StringLength);
2961 if (auto *C = Entry.second)
2962 return ConstantAddress(C, CharUnits::fromQuantity(C->getAlignment()));
2964 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty);
2965 llvm::Constant *Zeros[] = { Zero, Zero };
2967 // If we don't already have it, get _NSConstantStringClassReference.
2968 if (!ConstantStringClassRef) {
2969 std::string StringClass(getLangOpts().ObjCConstantStringClass);
2970 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy);
2972 if (LangOpts.ObjCRuntime.isNonFragile()) {
2974 StringClass.empty() ? "OBJC_CLASS_$_NSConstantString"
2975 : "OBJC_CLASS_$_" + StringClass;
2976 GV = getObjCRuntime().GetClassGlobal(str);
2977 // Make sure the result is of the correct type.
2978 llvm::Type *PTy = llvm::PointerType::getUnqual(Ty);
2979 V = llvm::ConstantExpr::getBitCast(GV, PTy);
2980 ConstantStringClassRef = V;
2983 StringClass.empty() ? "_NSConstantStringClassReference"
2984 : "_" + StringClass + "ClassReference";
2985 llvm::Type *PTy = llvm::ArrayType::get(Ty, 0);
2986 GV = CreateRuntimeVariable(PTy, str);
2987 // Decay array -> ptr
2988 V = llvm::ConstantExpr::getGetElementPtr(PTy, GV, Zeros);
2989 ConstantStringClassRef = V;
2992 V = ConstantStringClassRef;
2994 if (!NSConstantStringType) {
2995 // Construct the type for a constant NSString.
2996 RecordDecl *D = Context.buildImplicitRecord("__builtin_NSString");
2997 D->startDefinition();
2999 QualType FieldTypes[3];
3002 FieldTypes[0] = Context.getPointerType(Context.IntTy.withConst());
3004 FieldTypes[1] = Context.getPointerType(Context.CharTy.withConst());
3005 // unsigned int length;
3006 FieldTypes[2] = Context.UnsignedIntTy;
3009 for (unsigned i = 0; i < 3; ++i) {
3010 FieldDecl *Field = FieldDecl::Create(Context, D,
3012 SourceLocation(), nullptr,
3013 FieldTypes[i], /*TInfo=*/nullptr,
3014 /*BitWidth=*/nullptr,
3017 Field->setAccess(AS_public);
3021 D->completeDefinition();
3022 QualType NSTy = Context.getTagDeclType(D);
3023 NSConstantStringType = cast<llvm::StructType>(getTypes().ConvertType(NSTy));
3026 llvm::Constant *Fields[3];
3029 Fields[0] = cast<llvm::ConstantExpr>(V);
3033 llvm::ConstantDataArray::getString(VMContext, Entry.first());
3035 llvm::GlobalValue::LinkageTypes Linkage;
3037 Linkage = llvm::GlobalValue::PrivateLinkage;
3038 isConstant = !LangOpts.WritableStrings;
3040 auto *GV = new llvm::GlobalVariable(getModule(), C->getType(), isConstant,
3041 Linkage, C, ".str");
3042 GV->setUnnamedAddr(true);
3043 // Don't enforce the target's minimum global alignment, since the only use
3044 // of the string is via this class initializer.
3045 CharUnits Align = getContext().getTypeAlignInChars(getContext().CharTy);
3046 GV->setAlignment(Align.getQuantity());
3048 llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV, Zeros);
3051 llvm::Type *Ty = getTypes().ConvertType(getContext().UnsignedIntTy);
3052 Fields[2] = llvm::ConstantInt::get(Ty, StringLength);
3055 CharUnits Alignment = getPointerAlign();
3056 C = llvm::ConstantStruct::get(NSConstantStringType, Fields);
3057 GV = new llvm::GlobalVariable(getModule(), C->getType(), true,
3058 llvm::GlobalVariable::PrivateLinkage, C,
3059 "_unnamed_nsstring_");
3060 GV->setAlignment(Alignment.getQuantity());
3061 const char *NSStringSection = "__OBJC,__cstring_object,regular,no_dead_strip";
3062 const char *NSStringNonFragileABISection =
3063 "__DATA,__objc_stringobj,regular,no_dead_strip";
3064 // FIXME. Fix section.
3065 GV->setSection(LangOpts.ObjCRuntime.isNonFragile()
3066 ? NSStringNonFragileABISection
3070 return ConstantAddress(GV, Alignment);
3073 QualType CodeGenModule::getObjCFastEnumerationStateType() {
3074 if (ObjCFastEnumerationStateType.isNull()) {
3075 RecordDecl *D = Context.buildImplicitRecord("__objcFastEnumerationState");
3076 D->startDefinition();
3078 QualType FieldTypes[] = {
3079 Context.UnsignedLongTy,
3080 Context.getPointerType(Context.getObjCIdType()),
3081 Context.getPointerType(Context.UnsignedLongTy),
3082 Context.getConstantArrayType(Context.UnsignedLongTy,
3083 llvm::APInt(32, 5), ArrayType::Normal, 0)
3086 for (size_t i = 0; i < 4; ++i) {
3087 FieldDecl *Field = FieldDecl::Create(Context,
3090 SourceLocation(), nullptr,
3091 FieldTypes[i], /*TInfo=*/nullptr,
3092 /*BitWidth=*/nullptr,
3095 Field->setAccess(AS_public);
3099 D->completeDefinition();
3100 ObjCFastEnumerationStateType = Context.getTagDeclType(D);
3103 return ObjCFastEnumerationStateType;
3107 CodeGenModule::GetConstantArrayFromStringLiteral(const StringLiteral *E) {
3108 assert(!E->getType()->isPointerType() && "Strings are always arrays");
3110 // Don't emit it as the address of the string, emit the string data itself
3111 // as an inline array.
3112 if (E->getCharByteWidth() == 1) {
3113 SmallString<64> Str(E->getString());
3115 // Resize the string to the right size, which is indicated by its type.
3116 const ConstantArrayType *CAT = Context.getAsConstantArrayType(E->getType());
3117 Str.resize(CAT->getSize().getZExtValue());
3118 return llvm::ConstantDataArray::getString(VMContext, Str, false);
3121 auto *AType = cast<llvm::ArrayType>(getTypes().ConvertType(E->getType()));
3122 llvm::Type *ElemTy = AType->getElementType();
3123 unsigned NumElements = AType->getNumElements();
3125 // Wide strings have either 2-byte or 4-byte elements.
3126 if (ElemTy->getPrimitiveSizeInBits() == 16) {
3127 SmallVector<uint16_t, 32> Elements;
3128 Elements.reserve(NumElements);
3130 for(unsigned i = 0, e = E->getLength(); i != e; ++i)
3131 Elements.push_back(E->getCodeUnit(i));
3132 Elements.resize(NumElements);
3133 return llvm::ConstantDataArray::get(VMContext, Elements);
3136 assert(ElemTy->getPrimitiveSizeInBits() == 32);
3137 SmallVector<uint32_t, 32> Elements;
3138 Elements.reserve(NumElements);
3140 for(unsigned i = 0, e = E->getLength(); i != e; ++i)
3141 Elements.push_back(E->getCodeUnit(i));
3142 Elements.resize(NumElements);
3143 return llvm::ConstantDataArray::get(VMContext, Elements);
3146 static llvm::GlobalVariable *
3147 GenerateStringLiteral(llvm::Constant *C, llvm::GlobalValue::LinkageTypes LT,
3148 CodeGenModule &CGM, StringRef GlobalName,
3149 CharUnits Alignment) {
3150 // OpenCL v1.2 s6.5.3: a string literal is in the constant address space.
3151 unsigned AddrSpace = 0;
3152 if (CGM.getLangOpts().OpenCL)
3153 AddrSpace = CGM.getContext().getTargetAddressSpace(LangAS::opencl_constant);
3155 llvm::Module &M = CGM.getModule();
3156 // Create a global variable for this string
3157 auto *GV = new llvm::GlobalVariable(
3158 M, C->getType(), !CGM.getLangOpts().WritableStrings, LT, C, GlobalName,
3159 nullptr, llvm::GlobalVariable::NotThreadLocal, AddrSpace);
3160 GV->setAlignment(Alignment.getQuantity());
3161 GV->setUnnamedAddr(true);
3162 if (GV->isWeakForLinker()) {
3163 assert(CGM.supportsCOMDAT() && "Only COFF uses weak string literals");
3164 GV->setComdat(M.getOrInsertComdat(GV->getName()));
3170 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a
3171 /// constant array for the given string literal.
3173 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S,
3175 CharUnits Alignment = getContext().getAlignOfGlobalVarInChars(S->getType());
3177 llvm::Constant *C = GetConstantArrayFromStringLiteral(S);
3178 llvm::GlobalVariable **Entry = nullptr;
3179 if (!LangOpts.WritableStrings) {
3180 Entry = &ConstantStringMap[C];
3181 if (auto GV = *Entry) {
3182 if (Alignment.getQuantity() > GV->getAlignment())
3183 GV->setAlignment(Alignment.getQuantity());
3184 return ConstantAddress(GV, Alignment);
3188 SmallString<256> MangledNameBuffer;
3189 StringRef GlobalVariableName;
3190 llvm::GlobalValue::LinkageTypes LT;
3192 // Mangle the string literal if the ABI allows for it. However, we cannot
3193 // do this if we are compiling with ASan or -fwritable-strings because they
3194 // rely on strings having normal linkage.
3195 if (!LangOpts.WritableStrings &&
3196 !LangOpts.Sanitize.has(SanitizerKind::Address) &&
3197 getCXXABI().getMangleContext().shouldMangleStringLiteral(S)) {
3198 llvm::raw_svector_ostream Out(MangledNameBuffer);
3199 getCXXABI().getMangleContext().mangleStringLiteral(S, Out);
3201 LT = llvm::GlobalValue::LinkOnceODRLinkage;
3202 GlobalVariableName = MangledNameBuffer;
3204 LT = llvm::GlobalValue::PrivateLinkage;
3205 GlobalVariableName = Name;
3208 auto GV = GenerateStringLiteral(C, LT, *this, GlobalVariableName, Alignment);
3212 SanitizerMD->reportGlobalToASan(GV, S->getStrTokenLoc(0), "<string literal>",
3214 return ConstantAddress(GV, Alignment);
3217 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant
3218 /// array for the given ObjCEncodeExpr node.
3220 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) {
3222 getContext().getObjCEncodingForType(E->getEncodedType(), Str);
3224 return GetAddrOfConstantCString(Str);
3227 /// GetAddrOfConstantCString - Returns a pointer to a character array containing
3228 /// the literal and a terminating '\0' character.
3229 /// The result has pointer to array type.
3230 ConstantAddress CodeGenModule::GetAddrOfConstantCString(
3231 const std::string &Str, const char *GlobalName) {
3232 StringRef StrWithNull(Str.c_str(), Str.size() + 1);
3233 CharUnits Alignment =
3234 getContext().getAlignOfGlobalVarInChars(getContext().CharTy);
3237 llvm::ConstantDataArray::getString(getLLVMContext(), StrWithNull, false);
3239 // Don't share any string literals if strings aren't constant.
3240 llvm::GlobalVariable **Entry = nullptr;
3241 if (!LangOpts.WritableStrings) {
3242 Entry = &ConstantStringMap[C];
3243 if (auto GV = *Entry) {
3244 if (Alignment.getQuantity() > GV->getAlignment())
3245 GV->setAlignment(Alignment.getQuantity());
3246 return ConstantAddress(GV, Alignment);
3250 // Get the default prefix if a name wasn't specified.
3252 GlobalName = ".str";
3253 // Create a global variable for this.
3254 auto GV = GenerateStringLiteral(C, llvm::GlobalValue::PrivateLinkage, *this,
3255 GlobalName, Alignment);
3258 return ConstantAddress(GV, Alignment);
3261 ConstantAddress CodeGenModule::GetAddrOfGlobalTemporary(
3262 const MaterializeTemporaryExpr *E, const Expr *Init) {
3263 assert((E->getStorageDuration() == SD_Static ||
3264 E->getStorageDuration() == SD_Thread) && "not a global temporary");
3265 const auto *VD = cast<VarDecl>(E->getExtendingDecl());
3267 // If we're not materializing a subobject of the temporary, keep the
3268 // cv-qualifiers from the type of the MaterializeTemporaryExpr.
3269 QualType MaterializedType = Init->getType();
3270 if (Init == E->GetTemporaryExpr())
3271 MaterializedType = E->getType();
3273 CharUnits Align = getContext().getTypeAlignInChars(MaterializedType);
3275 if (llvm::Constant *Slot = MaterializedGlobalTemporaryMap[E])
3276 return ConstantAddress(Slot, Align);
3278 // FIXME: If an externally-visible declaration extends multiple temporaries,
3279 // we need to give each temporary the same name in every translation unit (and
3280 // we also need to make the temporaries externally-visible).
3281 SmallString<256> Name;
3282 llvm::raw_svector_ostream Out(Name);
3283 getCXXABI().getMangleContext().mangleReferenceTemporary(
3284 VD, E->getManglingNumber(), Out);
3286 APValue *Value = nullptr;
3287 if (E->getStorageDuration() == SD_Static) {
3288 // We might have a cached constant initializer for this temporary. Note
3289 // that this might have a different value from the value computed by
3290 // evaluating the initializer if the surrounding constant expression
3291 // modifies the temporary.
3292 Value = getContext().getMaterializedTemporaryValue(E, false);
3293 if (Value && Value->isUninit())
3297 // Try evaluating it now, it might have a constant initializer.
3298 Expr::EvalResult EvalResult;
3299 if (!Value && Init->EvaluateAsRValue(EvalResult, getContext()) &&
3300 !EvalResult.hasSideEffects())
3301 Value = &EvalResult.Val;
3303 llvm::Constant *InitialValue = nullptr;
3304 bool Constant = false;
3307 // The temporary has a constant initializer, use it.
3308 InitialValue = EmitConstantValue(*Value, MaterializedType, nullptr);
3309 Constant = isTypeConstant(MaterializedType, /*ExcludeCtor*/Value);
3310 Type = InitialValue->getType();
3312 // No initializer, the initialization will be provided when we
3313 // initialize the declaration which performed lifetime extension.
3314 Type = getTypes().ConvertTypeForMem(MaterializedType);
3317 // Create a global variable for this lifetime-extended temporary.
3318 llvm::GlobalValue::LinkageTypes Linkage =
3319 getLLVMLinkageVarDefinition(VD, Constant);
3320 if (Linkage == llvm::GlobalVariable::ExternalLinkage) {
3321 const VarDecl *InitVD;
3322 if (VD->isStaticDataMember() && VD->getAnyInitializer(InitVD) &&
3323 isa<CXXRecordDecl>(InitVD->getLexicalDeclContext())) {
3324 // Temporaries defined inside a class get linkonce_odr linkage because the
3325 // class can be defined in multipe translation units.
3326 Linkage = llvm::GlobalVariable::LinkOnceODRLinkage;
3328 // There is no need for this temporary to have external linkage if the
3329 // VarDecl has external linkage.
3330 Linkage = llvm::GlobalVariable::InternalLinkage;
3333 unsigned AddrSpace = GetGlobalVarAddressSpace(
3334 VD, getContext().getTargetAddressSpace(MaterializedType));
3335 auto *GV = new llvm::GlobalVariable(
3336 getModule(), Type, Constant, Linkage, InitialValue, Name.c_str(),
3337 /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal,
3339 setGlobalVisibility(GV, VD);
3340 GV->setAlignment(Align.getQuantity());
3341 if (supportsCOMDAT() && GV->isWeakForLinker())
3342 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
3343 if (VD->getTLSKind())
3344 setTLSMode(GV, *VD);
3345 MaterializedGlobalTemporaryMap[E] = GV;
3346 return ConstantAddress(GV, Align);
3349 /// EmitObjCPropertyImplementations - Emit information for synthesized
3350 /// properties for an implementation.
3351 void CodeGenModule::EmitObjCPropertyImplementations(const
3352 ObjCImplementationDecl *D) {
3353 for (const auto *PID : D->property_impls()) {
3354 // Dynamic is just for type-checking.
3355 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) {
3356 ObjCPropertyDecl *PD = PID->getPropertyDecl();
3358 // Determine which methods need to be implemented, some may have
3359 // been overridden. Note that ::isPropertyAccessor is not the method
3360 // we want, that just indicates if the decl came from a
3361 // property. What we want to know is if the method is defined in
3362 // this implementation.
3363 if (!D->getInstanceMethod(PD->getGetterName()))
3364 CodeGenFunction(*this).GenerateObjCGetter(
3365 const_cast<ObjCImplementationDecl *>(D), PID);
3366 if (!PD->isReadOnly() &&
3367 !D->getInstanceMethod(PD->getSetterName()))
3368 CodeGenFunction(*this).GenerateObjCSetter(
3369 const_cast<ObjCImplementationDecl *>(D), PID);
3374 static bool needsDestructMethod(ObjCImplementationDecl *impl) {
3375 const ObjCInterfaceDecl *iface = impl->getClassInterface();
3376 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
3377 ivar; ivar = ivar->getNextIvar())
3378 if (ivar->getType().isDestructedType())
3384 static bool AllTrivialInitializers(CodeGenModule &CGM,
3385 ObjCImplementationDecl *D) {
3386 CodeGenFunction CGF(CGM);
3387 for (ObjCImplementationDecl::init_iterator B = D->init_begin(),
3388 E = D->init_end(); B != E; ++B) {
3389 CXXCtorInitializer *CtorInitExp = *B;
3390 Expr *Init = CtorInitExp->getInit();
3391 if (!CGF.isTrivialInitializer(Init))
3397 /// EmitObjCIvarInitializations - Emit information for ivar initialization
3398 /// for an implementation.
3399 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) {
3400 // We might need a .cxx_destruct even if we don't have any ivar initializers.
3401 if (needsDestructMethod(D)) {
3402 IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct");
3403 Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
3404 ObjCMethodDecl *DTORMethod =
3405 ObjCMethodDecl::Create(getContext(), D->getLocation(), D->getLocation(),
3406 cxxSelector, getContext().VoidTy, nullptr, D,
3407 /*isInstance=*/true, /*isVariadic=*/false,
3408 /*isPropertyAccessor=*/true, /*isImplicitlyDeclared=*/true,
3409 /*isDefined=*/false, ObjCMethodDecl::Required);
3410 D->addInstanceMethod(DTORMethod);
3411 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false);
3412 D->setHasDestructors(true);
3415 // If the implementation doesn't have any ivar initializers, we don't need
3416 // a .cxx_construct.
3417 if (D->getNumIvarInitializers() == 0 ||
3418 AllTrivialInitializers(*this, D))
3421 IdentifierInfo *II = &getContext().Idents.get(".cxx_construct");
3422 Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
3423 // The constructor returns 'self'.
3424 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create(getContext(),
3428 getContext().getObjCIdType(),
3429 nullptr, D, /*isInstance=*/true,
3430 /*isVariadic=*/false,
3431 /*isPropertyAccessor=*/true,
3432 /*isImplicitlyDeclared=*/true,
3433 /*isDefined=*/false,
3434 ObjCMethodDecl::Required);
3435 D->addInstanceMethod(CTORMethod);
3436 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true);
3437 D->setHasNonZeroConstructors(true);
3440 /// EmitNamespace - Emit all declarations in a namespace.
3441 void CodeGenModule::EmitNamespace(const NamespaceDecl *ND) {
3442 for (auto *I : ND->decls()) {
3443 if (const auto *VD = dyn_cast<VarDecl>(I))
3444 if (VD->getTemplateSpecializationKind() != TSK_ExplicitSpecialization &&
3445 VD->getTemplateSpecializationKind() != TSK_Undeclared)
3447 EmitTopLevelDecl(I);
3451 // EmitLinkageSpec - Emit all declarations in a linkage spec.
3452 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) {
3453 if (LSD->getLanguage() != LinkageSpecDecl::lang_c &&
3454 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) {
3455 ErrorUnsupported(LSD, "linkage spec");
3459 for (auto *I : LSD->decls()) {
3460 // Meta-data for ObjC class includes references to implemented methods.
3461 // Generate class's method definitions first.
3462 if (auto *OID = dyn_cast<ObjCImplDecl>(I)) {
3463 for (auto *M : OID->methods())
3464 EmitTopLevelDecl(M);
3466 EmitTopLevelDecl(I);
3470 /// EmitTopLevelDecl - Emit code for a single top level declaration.
3471 void CodeGenModule::EmitTopLevelDecl(Decl *D) {
3472 // Ignore dependent declarations.
3473 if (D->getDeclContext() && D->getDeclContext()->isDependentContext())
3476 switch (D->getKind()) {
3477 case Decl::CXXConversion:
3478 case Decl::CXXMethod:
3479 case Decl::Function:
3480 // Skip function templates
3481 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() ||
3482 cast<FunctionDecl>(D)->isLateTemplateParsed())
3485 EmitGlobal(cast<FunctionDecl>(D));
3486 // Always provide some coverage mapping
3487 // even for the functions that aren't emitted.
3488 AddDeferredUnusedCoverageMapping(D);
3492 // Skip variable templates
3493 if (cast<VarDecl>(D)->getDescribedVarTemplate())
3495 case Decl::VarTemplateSpecialization:
3496 EmitGlobal(cast<VarDecl>(D));
3499 // Indirect fields from global anonymous structs and unions can be
3500 // ignored; only the actual variable requires IR gen support.
3501 case Decl::IndirectField:
3505 case Decl::Namespace:
3506 EmitNamespace(cast<NamespaceDecl>(D));
3508 // No code generation needed.
3509 case Decl::UsingShadow:
3510 case Decl::ClassTemplate:
3511 case Decl::VarTemplate:
3512 case Decl::VarTemplatePartialSpecialization:
3513 case Decl::FunctionTemplate:
3514 case Decl::TypeAliasTemplate:
3518 case Decl::Using: // using X; [C++]
3519 if (CGDebugInfo *DI = getModuleDebugInfo())
3520 DI->EmitUsingDecl(cast<UsingDecl>(*D));
3522 case Decl::NamespaceAlias:
3523 if (CGDebugInfo *DI = getModuleDebugInfo())
3524 DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(*D));
3526 case Decl::UsingDirective: // using namespace X; [C++]
3527 if (CGDebugInfo *DI = getModuleDebugInfo())
3528 DI->EmitUsingDirective(cast<UsingDirectiveDecl>(*D));
3530 case Decl::CXXConstructor:
3531 // Skip function templates
3532 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() ||
3533 cast<FunctionDecl>(D)->isLateTemplateParsed())
3536 getCXXABI().EmitCXXConstructors(cast<CXXConstructorDecl>(D));
3538 case Decl::CXXDestructor:
3539 if (cast<FunctionDecl>(D)->isLateTemplateParsed())
3541 getCXXABI().EmitCXXDestructors(cast<CXXDestructorDecl>(D));
3544 case Decl::StaticAssert:
3548 // Objective-C Decls
3550 // Forward declarations, no (immediate) code generation.
3551 case Decl::ObjCInterface:
3552 case Decl::ObjCCategory:
3555 case Decl::ObjCProtocol: {
3556 auto *Proto = cast<ObjCProtocolDecl>(D);
3557 if (Proto->isThisDeclarationADefinition())
3558 ObjCRuntime->GenerateProtocol(Proto);
3562 case Decl::ObjCCategoryImpl:
3563 // Categories have properties but don't support synthesize so we
3564 // can ignore them here.
3565 ObjCRuntime->GenerateCategory(cast<ObjCCategoryImplDecl>(D));
3568 case Decl::ObjCImplementation: {
3569 auto *OMD = cast<ObjCImplementationDecl>(D);
3570 EmitObjCPropertyImplementations(OMD);
3571 EmitObjCIvarInitializations(OMD);
3572 ObjCRuntime->GenerateClass(OMD);
3573 // Emit global variable debug information.
3574 if (CGDebugInfo *DI = getModuleDebugInfo())
3575 if (getCodeGenOpts().getDebugInfo() >= CodeGenOptions::LimitedDebugInfo)
3576 DI->getOrCreateInterfaceType(getContext().getObjCInterfaceType(
3577 OMD->getClassInterface()), OMD->getLocation());
3580 case Decl::ObjCMethod: {
3581 auto *OMD = cast<ObjCMethodDecl>(D);
3582 // If this is not a prototype, emit the body.
3584 CodeGenFunction(*this).GenerateObjCMethod(OMD);
3587 case Decl::ObjCCompatibleAlias:
3588 ObjCRuntime->RegisterAlias(cast<ObjCCompatibleAliasDecl>(D));
3591 case Decl::LinkageSpec:
3592 EmitLinkageSpec(cast<LinkageSpecDecl>(D));
3595 case Decl::FileScopeAsm: {
3596 // File-scope asm is ignored during device-side CUDA compilation.
3597 if (LangOpts.CUDA && LangOpts.CUDAIsDevice)
3599 auto *AD = cast<FileScopeAsmDecl>(D);
3600 getModule().appendModuleInlineAsm(AD->getAsmString()->getString());
3604 case Decl::Import: {
3605 auto *Import = cast<ImportDecl>(D);
3607 // Ignore import declarations that come from imported modules.
3608 if (Import->getImportedOwningModule())
3610 if (CGDebugInfo *DI = getModuleDebugInfo())
3611 DI->EmitImportDecl(*Import);
3613 ImportedModules.insert(Import->getImportedModule());
3617 case Decl::OMPThreadPrivate:
3618 EmitOMPThreadPrivateDecl(cast<OMPThreadPrivateDecl>(D));
3621 case Decl::ClassTemplateSpecialization: {
3622 const auto *Spec = cast<ClassTemplateSpecializationDecl>(D);
3624 Spec->getSpecializationKind() == TSK_ExplicitInstantiationDefinition &&
3625 Spec->hasDefinition())
3626 DebugInfo->completeTemplateDefinition(*Spec);
3631 // Make sure we handled everything we should, every other kind is a
3632 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind
3633 // function. Need to recode Decl::Kind to do that easily.
3634 assert(isa<TypeDecl>(D) && "Unsupported decl kind");
3639 void CodeGenModule::AddDeferredUnusedCoverageMapping(Decl *D) {
3640 // Do we need to generate coverage mapping?
3641 if (!CodeGenOpts.CoverageMapping)
3643 switch (D->getKind()) {
3644 case Decl::CXXConversion:
3645 case Decl::CXXMethod:
3646 case Decl::Function:
3647 case Decl::ObjCMethod:
3648 case Decl::CXXConstructor:
3649 case Decl::CXXDestructor: {
3650 if (!cast<FunctionDecl>(D)->doesThisDeclarationHaveABody())
3652 auto I = DeferredEmptyCoverageMappingDecls.find(D);
3653 if (I == DeferredEmptyCoverageMappingDecls.end())
3654 DeferredEmptyCoverageMappingDecls[D] = true;
3662 void CodeGenModule::ClearUnusedCoverageMapping(const Decl *D) {
3663 // Do we need to generate coverage mapping?
3664 if (!CodeGenOpts.CoverageMapping)
3666 if (const auto *Fn = dyn_cast<FunctionDecl>(D)) {
3667 if (Fn->isTemplateInstantiation())
3668 ClearUnusedCoverageMapping(Fn->getTemplateInstantiationPattern());
3670 auto I = DeferredEmptyCoverageMappingDecls.find(D);
3671 if (I == DeferredEmptyCoverageMappingDecls.end())
3672 DeferredEmptyCoverageMappingDecls[D] = false;
3677 void CodeGenModule::EmitDeferredUnusedCoverageMappings() {
3678 std::vector<const Decl *> DeferredDecls;
3679 for (const auto &I : DeferredEmptyCoverageMappingDecls) {
3682 DeferredDecls.push_back(I.first);
3684 // Sort the declarations by their location to make sure that the tests get a
3685 // predictable order for the coverage mapping for the unused declarations.
3686 if (CodeGenOpts.DumpCoverageMapping)
3687 std::sort(DeferredDecls.begin(), DeferredDecls.end(),
3688 [] (const Decl *LHS, const Decl *RHS) {
3689 return LHS->getLocStart() < RHS->getLocStart();
3691 for (const auto *D : DeferredDecls) {
3692 switch (D->getKind()) {
3693 case Decl::CXXConversion:
3694 case Decl::CXXMethod:
3695 case Decl::Function:
3696 case Decl::ObjCMethod: {
3697 CodeGenPGO PGO(*this);
3698 GlobalDecl GD(cast<FunctionDecl>(D));
3699 PGO.emitEmptyCounterMapping(D, getMangledName(GD),
3700 getFunctionLinkage(GD));
3703 case Decl::CXXConstructor: {
3704 CodeGenPGO PGO(*this);
3705 GlobalDecl GD(cast<CXXConstructorDecl>(D), Ctor_Base);
3706 PGO.emitEmptyCounterMapping(D, getMangledName(GD),
3707 getFunctionLinkage(GD));
3710 case Decl::CXXDestructor: {
3711 CodeGenPGO PGO(*this);
3712 GlobalDecl GD(cast<CXXDestructorDecl>(D), Dtor_Base);
3713 PGO.emitEmptyCounterMapping(D, getMangledName(GD),
3714 getFunctionLinkage(GD));
3723 /// Turns the given pointer into a constant.
3724 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context,
3726 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr);
3727 llvm::Type *i64 = llvm::Type::getInt64Ty(Context);
3728 return llvm::ConstantInt::get(i64, PtrInt);
3731 static void EmitGlobalDeclMetadata(CodeGenModule &CGM,
3732 llvm::NamedMDNode *&GlobalMetadata,
3734 llvm::GlobalValue *Addr) {
3735 if (!GlobalMetadata)
3737 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs");
3739 // TODO: should we report variant information for ctors/dtors?
3740 llvm::Metadata *Ops[] = {llvm::ConstantAsMetadata::get(Addr),
3741 llvm::ConstantAsMetadata::get(GetPointerConstant(
3742 CGM.getLLVMContext(), D.getDecl()))};
3743 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
3746 /// For each function which is declared within an extern "C" region and marked
3747 /// as 'used', but has internal linkage, create an alias from the unmangled
3748 /// name to the mangled name if possible. People expect to be able to refer
3749 /// to such functions with an unmangled name from inline assembly within the
3750 /// same translation unit.
3751 void CodeGenModule::EmitStaticExternCAliases() {
3752 for (auto &I : StaticExternCValues) {
3753 IdentifierInfo *Name = I.first;
3754 llvm::GlobalValue *Val = I.second;
3755 if (Val && !getModule().getNamedValue(Name->getName()))
3756 addUsedGlobal(llvm::GlobalAlias::create(Name->getName(), Val));
3760 bool CodeGenModule::lookupRepresentativeDecl(StringRef MangledName,
3761 GlobalDecl &Result) const {
3762 auto Res = Manglings.find(MangledName);
3763 if (Res == Manglings.end())
3765 Result = Res->getValue();
3769 /// Emits metadata nodes associating all the global values in the
3770 /// current module with the Decls they came from. This is useful for
3771 /// projects using IR gen as a subroutine.
3773 /// Since there's currently no way to associate an MDNode directly
3774 /// with an llvm::GlobalValue, we create a global named metadata
3775 /// with the name 'clang.global.decl.ptrs'.
3776 void CodeGenModule::EmitDeclMetadata() {
3777 llvm::NamedMDNode *GlobalMetadata = nullptr;
3779 for (auto &I : MangledDeclNames) {
3780 llvm::GlobalValue *Addr = getModule().getNamedValue(I.second);
3781 // Some mangled names don't necessarily have an associated GlobalValue
3782 // in this module, e.g. if we mangled it for DebugInfo.
3784 EmitGlobalDeclMetadata(*this, GlobalMetadata, I.first, Addr);
3788 /// Emits metadata nodes for all the local variables in the current
3790 void CodeGenFunction::EmitDeclMetadata() {
3791 if (LocalDeclMap.empty()) return;
3793 llvm::LLVMContext &Context = getLLVMContext();
3795 // Find the unique metadata ID for this name.
3796 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr");
3798 llvm::NamedMDNode *GlobalMetadata = nullptr;
3800 for (auto &I : LocalDeclMap) {
3801 const Decl *D = I.first;
3802 llvm::Value *Addr = I.second.getPointer();
3803 if (auto *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) {
3804 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D);
3805 Alloca->setMetadata(
3806 DeclPtrKind, llvm::MDNode::get(
3807 Context, llvm::ValueAsMetadata::getConstant(DAddr)));
3808 } else if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr)) {
3809 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D));
3810 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV);
3815 void CodeGenModule::EmitVersionIdentMetadata() {
3816 llvm::NamedMDNode *IdentMetadata =
3817 TheModule.getOrInsertNamedMetadata("llvm.ident");
3818 std::string Version = getClangFullVersion();
3819 llvm::LLVMContext &Ctx = TheModule.getContext();
3821 llvm::Metadata *IdentNode[] = {llvm::MDString::get(Ctx, Version)};
3822 IdentMetadata->addOperand(llvm::MDNode::get(Ctx, IdentNode));
3825 void CodeGenModule::EmitTargetMetadata() {
3826 // Warning, new MangledDeclNames may be appended within this loop.
3827 // We rely on MapVector insertions adding new elements to the end
3828 // of the container.
3829 // FIXME: Move this loop into the one target that needs it, and only
3830 // loop over those declarations for which we couldn't emit the target
3831 // metadata when we emitted the declaration.
3832 for (unsigned I = 0; I != MangledDeclNames.size(); ++I) {
3833 auto Val = *(MangledDeclNames.begin() + I);
3834 const Decl *D = Val.first.getDecl()->getMostRecentDecl();
3835 llvm::GlobalValue *GV = GetGlobalValue(Val.second);
3836 getTargetCodeGenInfo().emitTargetMD(D, GV, *this);
3840 void CodeGenModule::EmitCoverageFile() {
3841 if (!getCodeGenOpts().CoverageFile.empty()) {
3842 if (llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu")) {
3843 llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov");
3844 llvm::LLVMContext &Ctx = TheModule.getContext();
3845 llvm::MDString *CoverageFile =
3846 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageFile);
3847 for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) {
3848 llvm::MDNode *CU = CUNode->getOperand(i);
3849 llvm::Metadata *Elts[] = {CoverageFile, CU};
3850 GCov->addOperand(llvm::MDNode::get(Ctx, Elts));
3856 llvm::Constant *CodeGenModule::EmitUuidofInitializer(StringRef Uuid) {
3857 // Sema has checked that all uuid strings are of the form
3858 // "12345678-1234-1234-1234-1234567890ab".
3859 assert(Uuid.size() == 36);
3860 for (unsigned i = 0; i < 36; ++i) {
3861 if (i == 8 || i == 13 || i == 18 || i == 23) assert(Uuid[i] == '-');
3862 else assert(isHexDigit(Uuid[i]));
3865 // The starts of all bytes of Field3 in Uuid. Field 3 is "1234-1234567890ab".
3866 const unsigned Field3ValueOffsets[8] = { 19, 21, 24, 26, 28, 30, 32, 34 };
3868 llvm::Constant *Field3[8];
3869 for (unsigned Idx = 0; Idx < 8; ++Idx)
3870 Field3[Idx] = llvm::ConstantInt::get(
3871 Int8Ty, Uuid.substr(Field3ValueOffsets[Idx], 2), 16);
3873 llvm::Constant *Fields[4] = {
3874 llvm::ConstantInt::get(Int32Ty, Uuid.substr(0, 8), 16),
3875 llvm::ConstantInt::get(Int16Ty, Uuid.substr(9, 4), 16),
3876 llvm::ConstantInt::get(Int16Ty, Uuid.substr(14, 4), 16),
3877 llvm::ConstantArray::get(llvm::ArrayType::get(Int8Ty, 8), Field3)
3880 return llvm::ConstantStruct::getAnon(Fields);
3883 llvm::Constant *CodeGenModule::GetAddrOfRTTIDescriptor(QualType Ty,
3885 // Return a bogus pointer if RTTI is disabled, unless it's for EH.
3886 // FIXME: should we even be calling this method if RTTI is disabled
3887 // and it's not for EH?
3888 if (!ForEH && !getLangOpts().RTTI)
3889 return llvm::Constant::getNullValue(Int8PtrTy);
3891 if (ForEH && Ty->isObjCObjectPointerType() &&
3892 LangOpts.ObjCRuntime.isGNUFamily())
3893 return ObjCRuntime->GetEHType(Ty);
3895 return getCXXABI().getAddrOfRTTIDescriptor(Ty);
3898 void CodeGenModule::EmitOMPThreadPrivateDecl(const OMPThreadPrivateDecl *D) {
3899 for (auto RefExpr : D->varlists()) {
3900 auto *VD = cast<VarDecl>(cast<DeclRefExpr>(RefExpr)->getDecl());
3902 VD->getAnyInitializer() &&
3903 !VD->getAnyInitializer()->isConstantInitializer(getContext(),
3906 Address Addr(GetAddrOfGlobalVar(VD), getContext().getDeclAlign(VD));
3907 if (auto InitFunction = getOpenMPRuntime().emitThreadPrivateVarDefinition(
3908 VD, Addr, RefExpr->getLocStart(), PerformInit))
3909 CXXGlobalInits.push_back(InitFunction);
3913 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierForType(QualType T) {
3914 llvm::Metadata *&InternalId = MetadataIdMap[T.getCanonicalType()];
3918 if (isExternallyVisible(T->getLinkage())) {
3919 std::string OutName;
3920 llvm::raw_string_ostream Out(OutName);
3921 getCXXABI().getMangleContext().mangleTypeName(T, Out);
3923 InternalId = llvm::MDString::get(getLLVMContext(), Out.str());
3925 InternalId = llvm::MDNode::getDistinct(getLLVMContext(),
3926 llvm::ArrayRef<llvm::Metadata *>());
3932 void CodeGenModule::CreateVTableBitSetEntry(llvm::NamedMDNode *BitsetsMD,
3933 llvm::GlobalVariable *VTable,
3935 const CXXRecordDecl *RD) {
3936 llvm::Metadata *MD =
3937 CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0));
3938 llvm::Metadata *BitsetOps[] = {
3939 MD, llvm::ConstantAsMetadata::get(VTable),
3940 llvm::ConstantAsMetadata::get(
3941 llvm::ConstantInt::get(Int64Ty, Offset.getQuantity()))};
3942 BitsetsMD->addOperand(llvm::MDTuple::get(getLLVMContext(), BitsetOps));
3944 if (CodeGenOpts.SanitizeCfiCrossDso) {
3945 if (auto TypeId = CreateCfiIdForTypeMetadata(MD)) {
3946 llvm::Metadata *BitsetOps2[] = {
3947 llvm::ConstantAsMetadata::get(TypeId),
3948 llvm::ConstantAsMetadata::get(VTable),
3949 llvm::ConstantAsMetadata::get(
3950 llvm::ConstantInt::get(Int64Ty, Offset.getQuantity()))};
3951 BitsetsMD->addOperand(llvm::MDTuple::get(getLLVMContext(), BitsetOps2));
3956 // Fills in the supplied string map with the set of target features for the
3957 // passed in function.
3958 void CodeGenModule::getFunctionFeatureMap(llvm::StringMap<bool> &FeatureMap,
3959 const FunctionDecl *FD) {
3960 StringRef TargetCPU = Target.getTargetOpts().CPU;
3961 if (const auto *TD = FD->getAttr<TargetAttr>()) {
3962 // If we have a TargetAttr build up the feature map based on that.
3963 TargetAttr::ParsedTargetAttr ParsedAttr = TD->parse();
3965 // Make a copy of the features as passed on the command line into the
3966 // beginning of the additional features from the function to override.
3967 ParsedAttr.first.insert(ParsedAttr.first.begin(),
3968 Target.getTargetOpts().FeaturesAsWritten.begin(),
3969 Target.getTargetOpts().FeaturesAsWritten.end());
3971 if (ParsedAttr.second != "")
3972 TargetCPU = ParsedAttr.second;
3974 // Now populate the feature map, first with the TargetCPU which is either
3975 // the default or a new one from the target attribute string. Then we'll use
3976 // the passed in features (FeaturesAsWritten) along with the new ones from
3978 Target.initFeatureMap(FeatureMap, getDiags(), TargetCPU, ParsedAttr.first);
3980 Target.initFeatureMap(FeatureMap, getDiags(), TargetCPU,
3981 Target.getTargetOpts().Features);