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 "CGOpenMPRuntimeNVPTX.h"
24 #include "CodeGenFunction.h"
25 #include "CodeGenPGO.h"
26 #include "ConstantEmitter.h"
27 #include "CoverageMappingGen.h"
28 #include "TargetInfo.h"
29 #include "clang/AST/ASTContext.h"
30 #include "clang/AST/CharUnits.h"
31 #include "clang/AST/DeclCXX.h"
32 #include "clang/AST/DeclObjC.h"
33 #include "clang/AST/DeclTemplate.h"
34 #include "clang/AST/Mangle.h"
35 #include "clang/AST/RecordLayout.h"
36 #include "clang/AST/RecursiveASTVisitor.h"
37 #include "clang/Basic/Builtins.h"
38 #include "clang/Basic/CharInfo.h"
39 #include "clang/Basic/Diagnostic.h"
40 #include "clang/Basic/Module.h"
41 #include "clang/Basic/SourceManager.h"
42 #include "clang/Basic/TargetInfo.h"
43 #include "clang/Basic/Version.h"
44 #include "clang/CodeGen/ConstantInitBuilder.h"
45 #include "clang/Frontend/CodeGenOptions.h"
46 #include "clang/Sema/SemaDiagnostic.h"
47 #include "llvm/ADT/Triple.h"
48 #include "llvm/Analysis/TargetLibraryInfo.h"
49 #include "llvm/IR/CallSite.h"
50 #include "llvm/IR/CallingConv.h"
51 #include "llvm/IR/DataLayout.h"
52 #include "llvm/IR/Intrinsics.h"
53 #include "llvm/IR/LLVMContext.h"
54 #include "llvm/IR/Module.h"
55 #include "llvm/ProfileData/InstrProfReader.h"
56 #include "llvm/Support/ConvertUTF.h"
57 #include "llvm/Support/ErrorHandling.h"
58 #include "llvm/Support/MD5.h"
60 using namespace clang;
61 using namespace CodeGen;
63 static llvm::cl::opt<bool> LimitedCoverage(
64 "limited-coverage-experimental", llvm::cl::ZeroOrMore, llvm::cl::Hidden,
65 llvm::cl::desc("Emit limited coverage mapping information (experimental)"),
66 llvm::cl::init(false));
68 static const char AnnotationSection[] = "llvm.metadata";
70 static CGCXXABI *createCXXABI(CodeGenModule &CGM) {
71 switch (CGM.getTarget().getCXXABI().getKind()) {
72 case TargetCXXABI::GenericAArch64:
73 case TargetCXXABI::GenericARM:
74 case TargetCXXABI::iOS:
75 case TargetCXXABI::iOS64:
76 case TargetCXXABI::WatchOS:
77 case TargetCXXABI::GenericMIPS:
78 case TargetCXXABI::GenericItanium:
79 case TargetCXXABI::WebAssembly:
80 return CreateItaniumCXXABI(CGM);
81 case TargetCXXABI::Microsoft:
82 return CreateMicrosoftCXXABI(CGM);
85 llvm_unreachable("invalid C++ ABI kind");
88 CodeGenModule::CodeGenModule(ASTContext &C, const HeaderSearchOptions &HSO,
89 const PreprocessorOptions &PPO,
90 const CodeGenOptions &CGO, llvm::Module &M,
91 DiagnosticsEngine &diags,
92 CoverageSourceInfo *CoverageInfo)
93 : Context(C), LangOpts(C.getLangOpts()), HeaderSearchOpts(HSO),
94 PreprocessorOpts(PPO), CodeGenOpts(CGO), TheModule(M), Diags(diags),
95 Target(C.getTargetInfo()), ABI(createCXXABI(*this)),
96 VMContext(M.getContext()), Types(*this), VTables(*this),
97 SanitizerMD(new SanitizerMetadata(*this)) {
99 // Initialize the type cache.
100 llvm::LLVMContext &LLVMContext = M.getContext();
101 VoidTy = llvm::Type::getVoidTy(LLVMContext);
102 Int8Ty = llvm::Type::getInt8Ty(LLVMContext);
103 Int16Ty = llvm::Type::getInt16Ty(LLVMContext);
104 Int32Ty = llvm::Type::getInt32Ty(LLVMContext);
105 Int64Ty = llvm::Type::getInt64Ty(LLVMContext);
106 HalfTy = llvm::Type::getHalfTy(LLVMContext);
107 FloatTy = llvm::Type::getFloatTy(LLVMContext);
108 DoubleTy = llvm::Type::getDoubleTy(LLVMContext);
109 PointerWidthInBits = C.getTargetInfo().getPointerWidth(0);
110 PointerAlignInBytes =
111 C.toCharUnitsFromBits(C.getTargetInfo().getPointerAlign(0)).getQuantity();
113 C.toCharUnitsFromBits(C.getTargetInfo().getMaxPointerWidth()).getQuantity();
115 C.toCharUnitsFromBits(C.getTargetInfo().getIntAlign()).getQuantity();
116 IntTy = llvm::IntegerType::get(LLVMContext, C.getTargetInfo().getIntWidth());
117 IntPtrTy = llvm::IntegerType::get(LLVMContext,
118 C.getTargetInfo().getMaxPointerWidth());
119 Int8PtrTy = Int8Ty->getPointerTo(0);
120 Int8PtrPtrTy = Int8PtrTy->getPointerTo(0);
121 AllocaInt8PtrTy = Int8Ty->getPointerTo(
122 M.getDataLayout().getAllocaAddrSpace());
123 ASTAllocaAddressSpace = getTargetCodeGenInfo().getASTAllocaAddressSpace();
125 RuntimeCC = getTargetCodeGenInfo().getABIInfo().getRuntimeCC();
126 BuiltinCC = getTargetCodeGenInfo().getABIInfo().getBuiltinCC();
131 createOpenCLRuntime();
133 createOpenMPRuntime();
137 // Enable TBAA unless it's suppressed. ThreadSanitizer needs TBAA even at O0.
138 if (LangOpts.Sanitize.has(SanitizerKind::Thread) ||
139 (!CodeGenOpts.RelaxedAliasing && CodeGenOpts.OptimizationLevel > 0))
140 TBAA.reset(new CodeGenTBAA(Context, TheModule, CodeGenOpts, getLangOpts(),
141 getCXXABI().getMangleContext()));
143 // If debug info or coverage generation is enabled, create the CGDebugInfo
145 if (CodeGenOpts.getDebugInfo() != codegenoptions::NoDebugInfo ||
146 CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes)
147 DebugInfo.reset(new CGDebugInfo(*this));
149 Block.GlobalUniqueCount = 0;
151 if (C.getLangOpts().ObjC1)
152 ObjCData.reset(new ObjCEntrypoints());
154 if (CodeGenOpts.hasProfileClangUse()) {
155 auto ReaderOrErr = llvm::IndexedInstrProfReader::create(
156 CodeGenOpts.ProfileInstrumentUsePath);
157 if (auto E = ReaderOrErr.takeError()) {
158 unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
159 "Could not read profile %0: %1");
160 llvm::handleAllErrors(std::move(E), [&](const llvm::ErrorInfoBase &EI) {
161 getDiags().Report(DiagID) << CodeGenOpts.ProfileInstrumentUsePath
165 PGOReader = std::move(ReaderOrErr.get());
168 // If coverage mapping generation is enabled, create the
169 // CoverageMappingModuleGen object.
170 if (CodeGenOpts.CoverageMapping)
171 CoverageMapping.reset(new CoverageMappingModuleGen(*this, *CoverageInfo));
174 CodeGenModule::~CodeGenModule() {}
176 void CodeGenModule::createObjCRuntime() {
177 // This is just isGNUFamily(), but we want to force implementors of
178 // new ABIs to decide how best to do this.
179 switch (LangOpts.ObjCRuntime.getKind()) {
180 case ObjCRuntime::GNUstep:
181 case ObjCRuntime::GCC:
182 case ObjCRuntime::ObjFW:
183 ObjCRuntime.reset(CreateGNUObjCRuntime(*this));
186 case ObjCRuntime::FragileMacOSX:
187 case ObjCRuntime::MacOSX:
188 case ObjCRuntime::iOS:
189 case ObjCRuntime::WatchOS:
190 ObjCRuntime.reset(CreateMacObjCRuntime(*this));
193 llvm_unreachable("bad runtime kind");
196 void CodeGenModule::createOpenCLRuntime() {
197 OpenCLRuntime.reset(new CGOpenCLRuntime(*this));
200 void CodeGenModule::createOpenMPRuntime() {
201 // Select a specialized code generation class based on the target, if any.
202 // If it does not exist use the default implementation.
203 switch (getTriple().getArch()) {
204 case llvm::Triple::nvptx:
205 case llvm::Triple::nvptx64:
206 assert(getLangOpts().OpenMPIsDevice &&
207 "OpenMP NVPTX is only prepared to deal with device code.");
208 OpenMPRuntime.reset(new CGOpenMPRuntimeNVPTX(*this));
211 OpenMPRuntime.reset(new CGOpenMPRuntime(*this));
216 void CodeGenModule::createCUDARuntime() {
217 CUDARuntime.reset(CreateNVCUDARuntime(*this));
220 void CodeGenModule::addReplacement(StringRef Name, llvm::Constant *C) {
221 Replacements[Name] = C;
224 void CodeGenModule::applyReplacements() {
225 for (auto &I : Replacements) {
226 StringRef MangledName = I.first();
227 llvm::Constant *Replacement = I.second;
228 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
231 auto *OldF = cast<llvm::Function>(Entry);
232 auto *NewF = dyn_cast<llvm::Function>(Replacement);
234 if (auto *Alias = dyn_cast<llvm::GlobalAlias>(Replacement)) {
235 NewF = dyn_cast<llvm::Function>(Alias->getAliasee());
237 auto *CE = cast<llvm::ConstantExpr>(Replacement);
238 assert(CE->getOpcode() == llvm::Instruction::BitCast ||
239 CE->getOpcode() == llvm::Instruction::GetElementPtr);
240 NewF = dyn_cast<llvm::Function>(CE->getOperand(0));
244 // Replace old with new, but keep the old order.
245 OldF->replaceAllUsesWith(Replacement);
247 NewF->removeFromParent();
248 OldF->getParent()->getFunctionList().insertAfter(OldF->getIterator(),
251 OldF->eraseFromParent();
255 void CodeGenModule::addGlobalValReplacement(llvm::GlobalValue *GV, llvm::Constant *C) {
256 GlobalValReplacements.push_back(std::make_pair(GV, C));
259 void CodeGenModule::applyGlobalValReplacements() {
260 for (auto &I : GlobalValReplacements) {
261 llvm::GlobalValue *GV = I.first;
262 llvm::Constant *C = I.second;
264 GV->replaceAllUsesWith(C);
265 GV->eraseFromParent();
269 // This is only used in aliases that we created and we know they have a
271 static const llvm::GlobalObject *getAliasedGlobal(
272 const llvm::GlobalIndirectSymbol &GIS) {
273 llvm::SmallPtrSet<const llvm::GlobalIndirectSymbol*, 4> Visited;
274 const llvm::Constant *C = &GIS;
276 C = C->stripPointerCasts();
277 if (auto *GO = dyn_cast<llvm::GlobalObject>(C))
279 // stripPointerCasts will not walk over weak aliases.
280 auto *GIS2 = dyn_cast<llvm::GlobalIndirectSymbol>(C);
283 if (!Visited.insert(GIS2).second)
285 C = GIS2->getIndirectSymbol();
289 void CodeGenModule::checkAliases() {
290 // Check if the constructed aliases are well formed. It is really unfortunate
291 // that we have to do this in CodeGen, but we only construct mangled names
292 // and aliases during codegen.
294 DiagnosticsEngine &Diags = getDiags();
295 for (const GlobalDecl &GD : Aliases) {
296 const auto *D = cast<ValueDecl>(GD.getDecl());
297 SourceLocation Location;
298 bool IsIFunc = D->hasAttr<IFuncAttr>();
299 if (const Attr *A = D->getDefiningAttr())
300 Location = A->getLocation();
302 llvm_unreachable("Not an alias or ifunc?");
303 StringRef MangledName = getMangledName(GD);
304 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
305 auto *Alias = cast<llvm::GlobalIndirectSymbol>(Entry);
306 const llvm::GlobalValue *GV = getAliasedGlobal(*Alias);
309 Diags.Report(Location, diag::err_cyclic_alias) << IsIFunc;
310 } else if (GV->isDeclaration()) {
312 Diags.Report(Location, diag::err_alias_to_undefined)
313 << IsIFunc << IsIFunc;
314 } else if (IsIFunc) {
315 // Check resolver function type.
316 llvm::FunctionType *FTy = dyn_cast<llvm::FunctionType>(
317 GV->getType()->getPointerElementType());
319 if (!FTy->getReturnType()->isPointerTy())
320 Diags.Report(Location, diag::err_ifunc_resolver_return);
321 if (FTy->getNumParams())
322 Diags.Report(Location, diag::err_ifunc_resolver_params);
325 llvm::Constant *Aliasee = Alias->getIndirectSymbol();
326 llvm::GlobalValue *AliaseeGV;
327 if (auto CE = dyn_cast<llvm::ConstantExpr>(Aliasee))
328 AliaseeGV = cast<llvm::GlobalValue>(CE->getOperand(0));
330 AliaseeGV = cast<llvm::GlobalValue>(Aliasee);
332 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) {
333 StringRef AliasSection = SA->getName();
334 if (AliasSection != AliaseeGV->getSection())
335 Diags.Report(SA->getLocation(), diag::warn_alias_with_section)
336 << AliasSection << IsIFunc << IsIFunc;
339 // We have to handle alias to weak aliases in here. LLVM itself disallows
340 // this since the object semantics would not match the IL one. For
341 // compatibility with gcc we implement it by just pointing the alias
342 // to its aliasee's aliasee. We also warn, since the user is probably
343 // expecting the link to be weak.
344 if (auto GA = dyn_cast<llvm::GlobalIndirectSymbol>(AliaseeGV)) {
345 if (GA->isInterposable()) {
346 Diags.Report(Location, diag::warn_alias_to_weak_alias)
347 << GV->getName() << GA->getName() << IsIFunc;
348 Aliasee = llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
349 GA->getIndirectSymbol(), Alias->getType());
350 Alias->setIndirectSymbol(Aliasee);
357 for (const GlobalDecl &GD : Aliases) {
358 StringRef MangledName = getMangledName(GD);
359 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
360 auto *Alias = dyn_cast<llvm::GlobalIndirectSymbol>(Entry);
361 Alias->replaceAllUsesWith(llvm::UndefValue::get(Alias->getType()));
362 Alias->eraseFromParent();
366 void CodeGenModule::clear() {
367 DeferredDeclsToEmit.clear();
369 OpenMPRuntime->clear();
372 void InstrProfStats::reportDiagnostics(DiagnosticsEngine &Diags,
373 StringRef MainFile) {
374 if (!hasDiagnostics())
376 if (VisitedInMainFile > 0 && VisitedInMainFile == MissingInMainFile) {
377 if (MainFile.empty())
378 MainFile = "<stdin>";
379 Diags.Report(diag::warn_profile_data_unprofiled) << MainFile;
382 Diags.Report(diag::warn_profile_data_out_of_date) << Visited << Mismatched;
385 Diags.Report(diag::warn_profile_data_missing) << Visited << Missing;
389 void CodeGenModule::Release() {
391 EmitVTablesOpportunistically();
392 applyGlobalValReplacements();
395 EmitCXXGlobalInitFunc();
396 EmitCXXGlobalDtorFunc();
397 EmitCXXThreadLocalInitFunc();
399 if (llvm::Function *ObjCInitFunction = ObjCRuntime->ModuleInitFunction())
400 AddGlobalCtor(ObjCInitFunction);
401 if (Context.getLangOpts().CUDA && !Context.getLangOpts().CUDAIsDevice &&
403 if (llvm::Function *CudaCtorFunction = CUDARuntime->makeModuleCtorFunction())
404 AddGlobalCtor(CudaCtorFunction);
405 if (llvm::Function *CudaDtorFunction = CUDARuntime->makeModuleDtorFunction())
406 AddGlobalDtor(CudaDtorFunction);
409 if (llvm::Function *OpenMPRegistrationFunction =
410 OpenMPRuntime->emitRegistrationFunction()) {
411 auto ComdatKey = OpenMPRegistrationFunction->hasComdat() ?
412 OpenMPRegistrationFunction : nullptr;
413 AddGlobalCtor(OpenMPRegistrationFunction, 0, ComdatKey);
416 getModule().setProfileSummary(PGOReader->getSummary().getMD(VMContext));
417 if (PGOStats.hasDiagnostics())
418 PGOStats.reportDiagnostics(getDiags(), getCodeGenOpts().MainFileName);
420 EmitCtorList(GlobalCtors, "llvm.global_ctors");
421 EmitCtorList(GlobalDtors, "llvm.global_dtors");
422 EmitGlobalAnnotations();
423 EmitStaticExternCAliases();
424 EmitDeferredUnusedCoverageMappings();
426 CoverageMapping->emit();
427 if (CodeGenOpts.SanitizeCfiCrossDso) {
428 CodeGenFunction(*this).EmitCfiCheckFail();
429 CodeGenFunction(*this).EmitCfiCheckStub();
431 emitAtAvailableLinkGuard();
436 if (CodeGenOpts.Autolink &&
437 (Context.getLangOpts().Modules || !LinkerOptionsMetadata.empty())) {
438 EmitModuleLinkOptions();
441 // Record mregparm value now so it is visible through rest of codegen.
442 if (Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86)
443 getModule().addModuleFlag(llvm::Module::Error, "NumRegisterParameters",
444 CodeGenOpts.NumRegisterParameters);
446 if (CodeGenOpts.DwarfVersion) {
447 // We actually want the latest version when there are conflicts.
448 // We can change from Warning to Latest if such mode is supported.
449 getModule().addModuleFlag(llvm::Module::Warning, "Dwarf Version",
450 CodeGenOpts.DwarfVersion);
452 if (CodeGenOpts.EmitCodeView) {
453 // Indicate that we want CodeView in the metadata.
454 getModule().addModuleFlag(llvm::Module::Warning, "CodeView", 1);
456 if (CodeGenOpts.OptimizationLevel > 0 && CodeGenOpts.StrictVTablePointers) {
457 // We don't support LTO with 2 with different StrictVTablePointers
458 // FIXME: we could support it by stripping all the information introduced
459 // by StrictVTablePointers.
461 getModule().addModuleFlag(llvm::Module::Error, "StrictVTablePointers",1);
463 llvm::Metadata *Ops[2] = {
464 llvm::MDString::get(VMContext, "StrictVTablePointers"),
465 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
466 llvm::Type::getInt32Ty(VMContext), 1))};
468 getModule().addModuleFlag(llvm::Module::Require,
469 "StrictVTablePointersRequirement",
470 llvm::MDNode::get(VMContext, Ops));
473 // We support a single version in the linked module. The LLVM
474 // parser will drop debug info with a different version number
475 // (and warn about it, too).
476 getModule().addModuleFlag(llvm::Module::Warning, "Debug Info Version",
477 llvm::DEBUG_METADATA_VERSION);
479 // We need to record the widths of enums and wchar_t, so that we can generate
480 // the correct build attributes in the ARM backend. wchar_size is also used by
481 // TargetLibraryInfo.
482 uint64_t WCharWidth =
483 Context.getTypeSizeInChars(Context.getWideCharType()).getQuantity();
484 getModule().addModuleFlag(llvm::Module::Error, "wchar_size", WCharWidth);
486 llvm::Triple::ArchType Arch = Context.getTargetInfo().getTriple().getArch();
487 if ( Arch == llvm::Triple::arm
488 || Arch == llvm::Triple::armeb
489 || Arch == llvm::Triple::thumb
490 || Arch == llvm::Triple::thumbeb) {
491 // The minimum width of an enum in bytes
492 uint64_t EnumWidth = Context.getLangOpts().ShortEnums ? 1 : 4;
493 getModule().addModuleFlag(llvm::Module::Error, "min_enum_size", EnumWidth);
496 if (CodeGenOpts.SanitizeCfiCrossDso) {
497 // Indicate that we want cross-DSO control flow integrity checks.
498 getModule().addModuleFlag(llvm::Module::Override, "Cross-DSO CFI", 1);
501 if (LangOpts.CUDAIsDevice && getTriple().isNVPTX()) {
502 // Indicate whether __nvvm_reflect should be configured to flush denormal
503 // floating point values to 0. (This corresponds to its "__CUDA_FTZ"
505 getModule().addModuleFlag(llvm::Module::Override, "nvvm-reflect-ftz",
506 LangOpts.CUDADeviceFlushDenormalsToZero ? 1 : 0);
509 // Emit OpenCL specific module metadata: OpenCL/SPIR version.
510 if (LangOpts.OpenCL) {
511 EmitOpenCLMetadata();
512 // Emit SPIR version.
513 if (getTriple().getArch() == llvm::Triple::spir ||
514 getTriple().getArch() == llvm::Triple::spir64) {
515 // SPIR v2.0 s2.12 - The SPIR version used by the module is stored in the
516 // opencl.spir.version named metadata.
517 llvm::Metadata *SPIRVerElts[] = {
518 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
519 Int32Ty, LangOpts.OpenCLVersion / 100)),
520 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
521 Int32Ty, (LangOpts.OpenCLVersion / 100 > 1) ? 0 : 2))};
522 llvm::NamedMDNode *SPIRVerMD =
523 TheModule.getOrInsertNamedMetadata("opencl.spir.version");
524 llvm::LLVMContext &Ctx = TheModule.getContext();
525 SPIRVerMD->addOperand(llvm::MDNode::get(Ctx, SPIRVerElts));
529 if (uint32_t PLevel = Context.getLangOpts().PICLevel) {
530 assert(PLevel < 3 && "Invalid PIC Level");
531 getModule().setPICLevel(static_cast<llvm::PICLevel::Level>(PLevel));
532 if (Context.getLangOpts().PIE)
533 getModule().setPIELevel(static_cast<llvm::PIELevel::Level>(PLevel));
536 SimplifyPersonality();
538 if (getCodeGenOpts().EmitDeclMetadata)
541 if (getCodeGenOpts().EmitGcovArcs || getCodeGenOpts().EmitGcovNotes)
545 DebugInfo->finalize();
547 EmitVersionIdentMetadata();
549 EmitTargetMetadata();
552 void CodeGenModule::EmitOpenCLMetadata() {
553 // SPIR v2.0 s2.13 - The OpenCL version used by the module is stored in the
554 // opencl.ocl.version named metadata node.
555 llvm::Metadata *OCLVerElts[] = {
556 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
557 Int32Ty, LangOpts.OpenCLVersion / 100)),
558 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
559 Int32Ty, (LangOpts.OpenCLVersion % 100) / 10))};
560 llvm::NamedMDNode *OCLVerMD =
561 TheModule.getOrInsertNamedMetadata("opencl.ocl.version");
562 llvm::LLVMContext &Ctx = TheModule.getContext();
563 OCLVerMD->addOperand(llvm::MDNode::get(Ctx, OCLVerElts));
566 void CodeGenModule::UpdateCompletedType(const TagDecl *TD) {
567 // Make sure that this type is translated.
568 Types.UpdateCompletedType(TD);
571 void CodeGenModule::RefreshTypeCacheForClass(const CXXRecordDecl *RD) {
572 // Make sure that this type is translated.
573 Types.RefreshTypeCacheForClass(RD);
576 llvm::MDNode *CodeGenModule::getTBAATypeInfo(QualType QTy) {
579 return TBAA->getTypeInfo(QTy);
582 TBAAAccessInfo CodeGenModule::getTBAAAccessInfo(QualType AccessType) {
583 // Pointee values may have incomplete types, but they shall never be
585 if (AccessType->isIncompleteType())
586 return TBAAAccessInfo::getIncompleteInfo();
588 uint64_t Size = Context.getTypeSizeInChars(AccessType).getQuantity();
589 return TBAAAccessInfo(getTBAATypeInfo(AccessType), Size);
593 CodeGenModule::getTBAAVTablePtrAccessInfo(llvm::Type *VTablePtrType) {
595 return TBAAAccessInfo();
596 return TBAA->getVTablePtrAccessInfo(VTablePtrType);
599 llvm::MDNode *CodeGenModule::getTBAAStructInfo(QualType QTy) {
602 return TBAA->getTBAAStructInfo(QTy);
605 llvm::MDNode *CodeGenModule::getTBAABaseTypeInfo(QualType QTy) {
608 return TBAA->getBaseTypeInfo(QTy);
611 llvm::MDNode *CodeGenModule::getTBAAAccessTagInfo(TBAAAccessInfo Info) {
614 return TBAA->getAccessTagInfo(Info);
617 TBAAAccessInfo CodeGenModule::mergeTBAAInfoForCast(TBAAAccessInfo SourceInfo,
618 TBAAAccessInfo TargetInfo) {
620 return TBAAAccessInfo();
621 return TBAA->mergeTBAAInfoForCast(SourceInfo, TargetInfo);
625 CodeGenModule::mergeTBAAInfoForConditionalOperator(TBAAAccessInfo InfoA,
626 TBAAAccessInfo InfoB) {
628 return TBAAAccessInfo();
629 return TBAA->mergeTBAAInfoForConditionalOperator(InfoA, InfoB);
632 void CodeGenModule::DecorateInstructionWithTBAA(llvm::Instruction *Inst,
633 TBAAAccessInfo TBAAInfo) {
634 if (llvm::MDNode *Tag = getTBAAAccessTagInfo(TBAAInfo))
635 Inst->setMetadata(llvm::LLVMContext::MD_tbaa, Tag);
638 void CodeGenModule::DecorateInstructionWithInvariantGroup(
639 llvm::Instruction *I, const CXXRecordDecl *RD) {
640 I->setMetadata(llvm::LLVMContext::MD_invariant_group,
641 llvm::MDNode::get(getLLVMContext(), {}));
644 void CodeGenModule::Error(SourceLocation loc, StringRef message) {
645 unsigned diagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, "%0");
646 getDiags().Report(Context.getFullLoc(loc), diagID) << message;
649 /// ErrorUnsupported - Print out an error that codegen doesn't support the
650 /// specified stmt yet.
651 void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type) {
652 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error,
653 "cannot compile this %0 yet");
654 std::string Msg = Type;
655 getDiags().Report(Context.getFullLoc(S->getLocStart()), DiagID)
656 << Msg << S->getSourceRange();
659 /// ErrorUnsupported - Print out an error that codegen doesn't support the
660 /// specified decl yet.
661 void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type) {
662 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error,
663 "cannot compile this %0 yet");
664 std::string Msg = Type;
665 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg;
668 llvm::ConstantInt *CodeGenModule::getSize(CharUnits size) {
669 return llvm::ConstantInt::get(SizeTy, size.getQuantity());
672 void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV,
674 ForDefinition_t IsForDefinition) const {
675 // Internal definitions always have default visibility.
676 if (GV->hasLocalLinkage()) {
677 GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
681 // Set visibility for definitions.
682 LinkageInfo LV = D->getLinkageAndVisibility();
683 if (LV.isVisibilityExplicit() ||
684 (IsForDefinition && !GV->hasAvailableExternallyLinkage()))
685 GV->setVisibility(GetLLVMVisibility(LV.getVisibility()));
688 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(StringRef S) {
689 return llvm::StringSwitch<llvm::GlobalVariable::ThreadLocalMode>(S)
690 .Case("global-dynamic", llvm::GlobalVariable::GeneralDynamicTLSModel)
691 .Case("local-dynamic", llvm::GlobalVariable::LocalDynamicTLSModel)
692 .Case("initial-exec", llvm::GlobalVariable::InitialExecTLSModel)
693 .Case("local-exec", llvm::GlobalVariable::LocalExecTLSModel);
696 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(
697 CodeGenOptions::TLSModel M) {
699 case CodeGenOptions::GeneralDynamicTLSModel:
700 return llvm::GlobalVariable::GeneralDynamicTLSModel;
701 case CodeGenOptions::LocalDynamicTLSModel:
702 return llvm::GlobalVariable::LocalDynamicTLSModel;
703 case CodeGenOptions::InitialExecTLSModel:
704 return llvm::GlobalVariable::InitialExecTLSModel;
705 case CodeGenOptions::LocalExecTLSModel:
706 return llvm::GlobalVariable::LocalExecTLSModel;
708 llvm_unreachable("Invalid TLS model!");
711 void CodeGenModule::setTLSMode(llvm::GlobalValue *GV, const VarDecl &D) const {
712 assert(D.getTLSKind() && "setting TLS mode on non-TLS var!");
714 llvm::GlobalValue::ThreadLocalMode TLM;
715 TLM = GetLLVMTLSModel(CodeGenOpts.getDefaultTLSModel());
717 // Override the TLS model if it is explicitly specified.
718 if (const TLSModelAttr *Attr = D.getAttr<TLSModelAttr>()) {
719 TLM = GetLLVMTLSModel(Attr->getModel());
722 GV->setThreadLocalMode(TLM);
725 StringRef CodeGenModule::getMangledName(GlobalDecl GD) {
726 GlobalDecl CanonicalGD = GD.getCanonicalDecl();
728 // Some ABIs don't have constructor variants. Make sure that base and
729 // complete constructors get mangled the same.
730 if (const auto *CD = dyn_cast<CXXConstructorDecl>(CanonicalGD.getDecl())) {
731 if (!getTarget().getCXXABI().hasConstructorVariants()) {
732 CXXCtorType OrigCtorType = GD.getCtorType();
733 assert(OrigCtorType == Ctor_Base || OrigCtorType == Ctor_Complete);
734 if (OrigCtorType == Ctor_Base)
735 CanonicalGD = GlobalDecl(CD, Ctor_Complete);
739 auto FoundName = MangledDeclNames.find(CanonicalGD);
740 if (FoundName != MangledDeclNames.end())
741 return FoundName->second;
743 const auto *ND = cast<NamedDecl>(GD.getDecl());
744 SmallString<256> Buffer;
746 if (getCXXABI().getMangleContext().shouldMangleDeclName(ND)) {
747 llvm::raw_svector_ostream Out(Buffer);
748 if (const auto *D = dyn_cast<CXXConstructorDecl>(ND))
749 getCXXABI().getMangleContext().mangleCXXCtor(D, GD.getCtorType(), Out);
750 else if (const auto *D = dyn_cast<CXXDestructorDecl>(ND))
751 getCXXABI().getMangleContext().mangleCXXDtor(D, GD.getDtorType(), Out);
753 getCXXABI().getMangleContext().mangleName(ND, Out);
756 IdentifierInfo *II = ND->getIdentifier();
757 assert(II && "Attempt to mangle unnamed decl.");
758 const auto *FD = dyn_cast<FunctionDecl>(ND);
761 FD->getType()->castAs<FunctionType>()->getCallConv() == CC_X86RegCall) {
762 llvm::raw_svector_ostream Out(Buffer);
763 Out << "__regcall3__" << II->getName();
770 // Keep the first result in the case of a mangling collision.
771 auto Result = Manglings.insert(std::make_pair(Str, GD));
772 return MangledDeclNames[CanonicalGD] = Result.first->first();
775 StringRef CodeGenModule::getBlockMangledName(GlobalDecl GD,
776 const BlockDecl *BD) {
777 MangleContext &MangleCtx = getCXXABI().getMangleContext();
778 const Decl *D = GD.getDecl();
780 SmallString<256> Buffer;
781 llvm::raw_svector_ostream Out(Buffer);
783 MangleCtx.mangleGlobalBlock(BD,
784 dyn_cast_or_null<VarDecl>(initializedGlobalDecl.getDecl()), Out);
785 else if (const auto *CD = dyn_cast<CXXConstructorDecl>(D))
786 MangleCtx.mangleCtorBlock(CD, GD.getCtorType(), BD, Out);
787 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(D))
788 MangleCtx.mangleDtorBlock(DD, GD.getDtorType(), BD, Out);
790 MangleCtx.mangleBlock(cast<DeclContext>(D), BD, Out);
792 auto Result = Manglings.insert(std::make_pair(Out.str(), BD));
793 return Result.first->first();
796 llvm::GlobalValue *CodeGenModule::GetGlobalValue(StringRef Name) {
797 return getModule().getNamedValue(Name);
800 /// AddGlobalCtor - Add a function to the list that will be called before
802 void CodeGenModule::AddGlobalCtor(llvm::Function *Ctor, int Priority,
803 llvm::Constant *AssociatedData) {
804 // FIXME: Type coercion of void()* types.
805 GlobalCtors.push_back(Structor(Priority, Ctor, AssociatedData));
808 /// AddGlobalDtor - Add a function to the list that will be called
809 /// when the module is unloaded.
810 void CodeGenModule::AddGlobalDtor(llvm::Function *Dtor, int Priority) {
811 // FIXME: Type coercion of void()* types.
812 GlobalDtors.push_back(Structor(Priority, Dtor, nullptr));
815 void CodeGenModule::EmitCtorList(CtorList &Fns, const char *GlobalName) {
816 if (Fns.empty()) return;
818 // Ctor function type is void()*.
819 llvm::FunctionType* CtorFTy = llvm::FunctionType::get(VoidTy, false);
820 llvm::Type *CtorPFTy = llvm::PointerType::getUnqual(CtorFTy);
822 // Get the type of a ctor entry, { i32, void ()*, i8* }.
823 llvm::StructType *CtorStructTy = llvm::StructType::get(
824 Int32Ty, llvm::PointerType::getUnqual(CtorFTy), VoidPtrTy);
826 // Construct the constructor and destructor arrays.
827 ConstantInitBuilder builder(*this);
828 auto ctors = builder.beginArray(CtorStructTy);
829 for (const auto &I : Fns) {
830 auto ctor = ctors.beginStruct(CtorStructTy);
831 ctor.addInt(Int32Ty, I.Priority);
832 ctor.add(llvm::ConstantExpr::getBitCast(I.Initializer, CtorPFTy));
833 if (I.AssociatedData)
834 ctor.add(llvm::ConstantExpr::getBitCast(I.AssociatedData, VoidPtrTy));
836 ctor.addNullPointer(VoidPtrTy);
837 ctor.finishAndAddTo(ctors);
841 ctors.finishAndCreateGlobal(GlobalName, getPointerAlign(),
843 llvm::GlobalValue::AppendingLinkage);
845 // The LTO linker doesn't seem to like it when we set an alignment
846 // on appending variables. Take it off as a workaround.
847 list->setAlignment(0);
852 llvm::GlobalValue::LinkageTypes
853 CodeGenModule::getFunctionLinkage(GlobalDecl GD) {
854 const auto *D = cast<FunctionDecl>(GD.getDecl());
856 GVALinkage Linkage = getContext().GetGVALinkageForFunction(D);
858 if (isa<CXXDestructorDecl>(D) &&
859 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
861 // Destructor variants in the Microsoft C++ ABI are always internal or
862 // linkonce_odr thunks emitted on an as-needed basis.
863 return Linkage == GVA_Internal ? llvm::GlobalValue::InternalLinkage
864 : llvm::GlobalValue::LinkOnceODRLinkage;
867 if (isa<CXXConstructorDecl>(D) &&
868 cast<CXXConstructorDecl>(D)->isInheritingConstructor() &&
869 Context.getTargetInfo().getCXXABI().isMicrosoft()) {
870 // Our approach to inheriting constructors is fundamentally different from
871 // that used by the MS ABI, so keep our inheriting constructor thunks
872 // internal rather than trying to pick an unambiguous mangling for them.
873 return llvm::GlobalValue::InternalLinkage;
876 return getLLVMLinkageForDeclarator(D, Linkage, /*isConstantVariable=*/false);
879 void CodeGenModule::setFunctionDLLStorageClass(GlobalDecl GD, llvm::Function *F) {
880 const auto *FD = cast<FunctionDecl>(GD.getDecl());
882 if (const auto *Dtor = dyn_cast_or_null<CXXDestructorDecl>(FD)) {
883 if (getCXXABI().useThunkForDtorVariant(Dtor, GD.getDtorType())) {
884 // Don't dllexport/import destructor thunks.
885 F->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
890 if (FD->hasAttr<DLLImportAttr>())
891 F->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
892 else if (FD->hasAttr<DLLExportAttr>())
893 F->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
895 F->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass);
898 llvm::ConstantInt *CodeGenModule::CreateCrossDsoCfiTypeId(llvm::Metadata *MD) {
899 llvm::MDString *MDS = dyn_cast<llvm::MDString>(MD);
900 if (!MDS) return nullptr;
902 return llvm::ConstantInt::get(Int64Ty, llvm::MD5Hash(MDS->getString()));
905 void CodeGenModule::setFunctionDefinitionAttributes(const FunctionDecl *D,
907 setNonAliasAttributes(D, F);
910 void CodeGenModule::SetLLVMFunctionAttributes(const Decl *D,
911 const CGFunctionInfo &Info,
913 unsigned CallingConv;
914 llvm::AttributeList PAL;
915 ConstructAttributeList(F->getName(), Info, D, PAL, CallingConv, false);
916 F->setAttributes(PAL);
917 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
920 /// Determines whether the language options require us to model
921 /// unwind exceptions. We treat -fexceptions as mandating this
922 /// except under the fragile ObjC ABI with only ObjC exceptions
923 /// enabled. This means, for example, that C with -fexceptions
925 static bool hasUnwindExceptions(const LangOptions &LangOpts) {
926 // If exceptions are completely disabled, obviously this is false.
927 if (!LangOpts.Exceptions) return false;
929 // If C++ exceptions are enabled, this is true.
930 if (LangOpts.CXXExceptions) return true;
932 // If ObjC exceptions are enabled, this depends on the ABI.
933 if (LangOpts.ObjCExceptions) {
934 return LangOpts.ObjCRuntime.hasUnwindExceptions();
940 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D,
944 if (CodeGenOpts.UnwindTables)
945 B.addAttribute(llvm::Attribute::UWTable);
947 if (!hasUnwindExceptions(LangOpts))
948 B.addAttribute(llvm::Attribute::NoUnwind);
950 if (LangOpts.getStackProtector() == LangOptions::SSPOn)
951 B.addAttribute(llvm::Attribute::StackProtect);
952 else if (LangOpts.getStackProtector() == LangOptions::SSPStrong)
953 B.addAttribute(llvm::Attribute::StackProtectStrong);
954 else if (LangOpts.getStackProtector() == LangOptions::SSPReq)
955 B.addAttribute(llvm::Attribute::StackProtectReq);
958 // If we don't have a declaration to control inlining, the function isn't
959 // explicitly marked as alwaysinline for semantic reasons, and inlining is
960 // disabled, mark the function as noinline.
961 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline) &&
962 CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining)
963 B.addAttribute(llvm::Attribute::NoInline);
965 F->addAttributes(llvm::AttributeList::FunctionIndex, B);
969 // Track whether we need to add the optnone LLVM attribute,
970 // starting with the default for this optimization level.
971 bool ShouldAddOptNone =
972 !CodeGenOpts.DisableO0ImplyOptNone && CodeGenOpts.OptimizationLevel == 0;
973 // We can't add optnone in the following cases, it won't pass the verifier.
974 ShouldAddOptNone &= !D->hasAttr<MinSizeAttr>();
975 ShouldAddOptNone &= !F->hasFnAttribute(llvm::Attribute::AlwaysInline);
976 ShouldAddOptNone &= !D->hasAttr<AlwaysInlineAttr>();
978 if (ShouldAddOptNone || D->hasAttr<OptimizeNoneAttr>()) {
979 B.addAttribute(llvm::Attribute::OptimizeNone);
981 // OptimizeNone implies noinline; we should not be inlining such functions.
982 B.addAttribute(llvm::Attribute::NoInline);
983 assert(!F->hasFnAttribute(llvm::Attribute::AlwaysInline) &&
984 "OptimizeNone and AlwaysInline on same function!");
986 // We still need to handle naked functions even though optnone subsumes
987 // much of their semantics.
988 if (D->hasAttr<NakedAttr>())
989 B.addAttribute(llvm::Attribute::Naked);
991 // OptimizeNone wins over OptimizeForSize and MinSize.
992 F->removeFnAttr(llvm::Attribute::OptimizeForSize);
993 F->removeFnAttr(llvm::Attribute::MinSize);
994 } else if (D->hasAttr<NakedAttr>()) {
995 // Naked implies noinline: we should not be inlining such functions.
996 B.addAttribute(llvm::Attribute::Naked);
997 B.addAttribute(llvm::Attribute::NoInline);
998 } else if (D->hasAttr<NoDuplicateAttr>()) {
999 B.addAttribute(llvm::Attribute::NoDuplicate);
1000 } else if (D->hasAttr<NoInlineAttr>()) {
1001 B.addAttribute(llvm::Attribute::NoInline);
1002 } else if (D->hasAttr<AlwaysInlineAttr>() &&
1003 !F->hasFnAttribute(llvm::Attribute::NoInline)) {
1004 // (noinline wins over always_inline, and we can't specify both in IR)
1005 B.addAttribute(llvm::Attribute::AlwaysInline);
1006 } else if (CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining) {
1007 // If we're not inlining, then force everything that isn't always_inline to
1008 // carry an explicit noinline attribute.
1009 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline))
1010 B.addAttribute(llvm::Attribute::NoInline);
1012 // Otherwise, propagate the inline hint attribute and potentially use its
1013 // absence to mark things as noinline.
1014 if (auto *FD = dyn_cast<FunctionDecl>(D)) {
1015 if (any_of(FD->redecls(), [&](const FunctionDecl *Redecl) {
1016 return Redecl->isInlineSpecified();
1018 B.addAttribute(llvm::Attribute::InlineHint);
1019 } else if (CodeGenOpts.getInlining() ==
1020 CodeGenOptions::OnlyHintInlining &&
1022 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) {
1023 B.addAttribute(llvm::Attribute::NoInline);
1028 // Add other optimization related attributes if we are optimizing this
1030 if (!D->hasAttr<OptimizeNoneAttr>()) {
1031 if (D->hasAttr<ColdAttr>()) {
1032 if (!ShouldAddOptNone)
1033 B.addAttribute(llvm::Attribute::OptimizeForSize);
1034 B.addAttribute(llvm::Attribute::Cold);
1037 if (D->hasAttr<MinSizeAttr>())
1038 B.addAttribute(llvm::Attribute::MinSize);
1041 F->addAttributes(llvm::AttributeList::FunctionIndex, B);
1043 unsigned alignment = D->getMaxAlignment() / Context.getCharWidth();
1045 F->setAlignment(alignment);
1047 // Some C++ ABIs require 2-byte alignment for member functions, in order to
1048 // reserve a bit for differentiating between virtual and non-virtual member
1049 // functions. If the current target's C++ ABI requires this and this is a
1050 // member function, set its alignment accordingly.
1051 if (getTarget().getCXXABI().areMemberFunctionsAligned()) {
1052 if (F->getAlignment() < 2 && isa<CXXMethodDecl>(D))
1056 // In the cross-dso CFI mode, we want !type attributes on definitions only.
1057 if (CodeGenOpts.SanitizeCfiCrossDso)
1058 if (auto *FD = dyn_cast<FunctionDecl>(D))
1059 CreateFunctionTypeMetadata(FD, F);
1062 void CodeGenModule::SetCommonAttributes(const Decl *D,
1063 llvm::GlobalValue *GV) {
1064 if (const auto *ND = dyn_cast_or_null<NamedDecl>(D))
1065 setGlobalVisibility(GV, ND, ForDefinition);
1067 GV->setVisibility(llvm::GlobalValue::DefaultVisibility);
1069 if (D && D->hasAttr<UsedAttr>())
1073 void CodeGenModule::setAliasAttributes(const Decl *D,
1074 llvm::GlobalValue *GV) {
1075 SetCommonAttributes(D, GV);
1077 // Process the dllexport attribute based on whether the original definition
1078 // (not necessarily the aliasee) was exported.
1079 if (D->hasAttr<DLLExportAttr>())
1080 GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
1083 void CodeGenModule::setNonAliasAttributes(const Decl *D,
1084 llvm::GlobalObject *GO) {
1085 SetCommonAttributes(D, GO);
1088 if (auto *GV = dyn_cast<llvm::GlobalVariable>(GO)) {
1089 if (auto *SA = D->getAttr<PragmaClangBSSSectionAttr>())
1090 GV->addAttribute("bss-section", SA->getName());
1091 if (auto *SA = D->getAttr<PragmaClangDataSectionAttr>())
1092 GV->addAttribute("data-section", SA->getName());
1093 if (auto *SA = D->getAttr<PragmaClangRodataSectionAttr>())
1094 GV->addAttribute("rodata-section", SA->getName());
1097 if (auto *F = dyn_cast<llvm::Function>(GO)) {
1098 if (auto *SA = D->getAttr<PragmaClangTextSectionAttr>())
1099 if (!D->getAttr<SectionAttr>())
1100 F->addFnAttr("implicit-section-name", SA->getName());
1103 if (const SectionAttr *SA = D->getAttr<SectionAttr>())
1104 GO->setSection(SA->getName());
1107 getTargetCodeGenInfo().setTargetAttributes(D, GO, *this, ForDefinition);
1110 void CodeGenModule::SetInternalFunctionAttributes(const Decl *D,
1112 const CGFunctionInfo &FI) {
1113 SetLLVMFunctionAttributes(D, FI, F);
1114 SetLLVMFunctionAttributesForDefinition(D, F);
1116 F->setLinkage(llvm::Function::InternalLinkage);
1118 setNonAliasAttributes(D, F);
1121 static void setLinkageForGV(llvm::GlobalValue *GV,
1122 const NamedDecl *ND) {
1123 // Set linkage and visibility in case we never see a definition.
1124 LinkageInfo LV = ND->getLinkageAndVisibility();
1125 if (!isExternallyVisible(LV.getLinkage())) {
1126 // Don't set internal linkage on declarations.
1128 if (ND->hasAttr<DLLImportAttr>()) {
1129 GV->setLinkage(llvm::GlobalValue::ExternalLinkage);
1130 GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
1131 } else if (ND->hasAttr<DLLExportAttr>()) {
1132 GV->setLinkage(llvm::GlobalValue::ExternalLinkage);
1133 } else if (ND->hasAttr<WeakAttr>() || ND->isWeakImported()) {
1134 // "extern_weak" is overloaded in LLVM; we probably should have
1135 // separate linkage types for this.
1136 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage);
1141 void CodeGenModule::CreateFunctionTypeMetadata(const FunctionDecl *FD,
1142 llvm::Function *F) {
1143 // Only if we are checking indirect calls.
1144 if (!LangOpts.Sanitize.has(SanitizerKind::CFIICall))
1147 // Non-static class methods are handled via vtable pointer checks elsewhere.
1148 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic())
1151 // Additionally, if building with cross-DSO support...
1152 if (CodeGenOpts.SanitizeCfiCrossDso) {
1153 // Skip available_externally functions. They won't be codegen'ed in the
1154 // current module anyway.
1155 if (getContext().GetGVALinkageForFunction(FD) == GVA_AvailableExternally)
1159 llvm::Metadata *MD = CreateMetadataIdentifierForType(FD->getType());
1160 F->addTypeMetadata(0, MD);
1161 F->addTypeMetadata(0, CreateMetadataIdentifierGeneralized(FD->getType()));
1163 // Emit a hash-based bit set entry for cross-DSO calls.
1164 if (CodeGenOpts.SanitizeCfiCrossDso)
1165 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD))
1166 F->addTypeMetadata(0, llvm::ConstantAsMetadata::get(CrossDsoTypeId));
1169 void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, llvm::Function *F,
1170 bool IsIncompleteFunction,
1172 ForDefinition_t IsForDefinition) {
1174 if (llvm::Intrinsic::ID IID = F->getIntrinsicID()) {
1175 // If this is an intrinsic function, set the function's attributes
1176 // to the intrinsic's attributes.
1177 F->setAttributes(llvm::Intrinsic::getAttributes(getLLVMContext(), IID));
1181 const auto *FD = cast<FunctionDecl>(GD.getDecl());
1183 if (!IsIncompleteFunction) {
1184 SetLLVMFunctionAttributes(FD, getTypes().arrangeGlobalDeclaration(GD), F);
1185 // Setup target-specific attributes.
1186 if (!IsForDefinition)
1187 getTargetCodeGenInfo().setTargetAttributes(FD, F, *this,
1191 // Add the Returned attribute for "this", except for iOS 5 and earlier
1192 // where substantial code, including the libstdc++ dylib, was compiled with
1193 // GCC and does not actually return "this".
1194 if (!IsThunk && getCXXABI().HasThisReturn(GD) &&
1195 !(getTriple().isiOS() && getTriple().isOSVersionLT(6))) {
1196 assert(!F->arg_empty() &&
1197 F->arg_begin()->getType()
1198 ->canLosslesslyBitCastTo(F->getReturnType()) &&
1199 "unexpected this return");
1200 F->addAttribute(1, llvm::Attribute::Returned);
1203 // Only a few attributes are set on declarations; these may later be
1204 // overridden by a definition.
1206 setLinkageForGV(F, FD);
1207 setGlobalVisibility(F, FD, NotForDefinition);
1209 if (FD->getAttr<PragmaClangTextSectionAttr>()) {
1210 F->addFnAttr("implicit-section-name");
1213 if (const SectionAttr *SA = FD->getAttr<SectionAttr>())
1214 F->setSection(SA->getName());
1216 if (FD->isReplaceableGlobalAllocationFunction()) {
1217 // A replaceable global allocation function does not act like a builtin by
1218 // default, only if it is invoked by a new-expression or delete-expression.
1219 F->addAttribute(llvm::AttributeList::FunctionIndex,
1220 llvm::Attribute::NoBuiltin);
1222 // A sane operator new returns a non-aliasing pointer.
1223 // FIXME: Also add NonNull attribute to the return value
1224 // for the non-nothrow forms?
1225 auto Kind = FD->getDeclName().getCXXOverloadedOperator();
1226 if (getCodeGenOpts().AssumeSaneOperatorNew &&
1227 (Kind == OO_New || Kind == OO_Array_New))
1228 F->addAttribute(llvm::AttributeList::ReturnIndex,
1229 llvm::Attribute::NoAlias);
1232 if (isa<CXXConstructorDecl>(FD) || isa<CXXDestructorDecl>(FD))
1233 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
1234 else if (const auto *MD = dyn_cast<CXXMethodDecl>(FD))
1235 if (MD->isVirtual())
1236 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
1238 // Don't emit entries for function declarations in the cross-DSO mode. This
1239 // is handled with better precision by the receiving DSO.
1240 if (!CodeGenOpts.SanitizeCfiCrossDso)
1241 CreateFunctionTypeMetadata(FD, F);
1243 if (getLangOpts().OpenMP && FD->hasAttr<OMPDeclareSimdDeclAttr>())
1244 getOpenMPRuntime().emitDeclareSimdFunction(FD, F);
1247 void CodeGenModule::addUsedGlobal(llvm::GlobalValue *GV) {
1248 assert(!GV->isDeclaration() &&
1249 "Only globals with definition can force usage.");
1250 LLVMUsed.emplace_back(GV);
1253 void CodeGenModule::addCompilerUsedGlobal(llvm::GlobalValue *GV) {
1254 assert(!GV->isDeclaration() &&
1255 "Only globals with definition can force usage.");
1256 LLVMCompilerUsed.emplace_back(GV);
1259 static void emitUsed(CodeGenModule &CGM, StringRef Name,
1260 std::vector<llvm::WeakTrackingVH> &List) {
1261 // Don't create llvm.used if there is no need.
1265 // Convert List to what ConstantArray needs.
1266 SmallVector<llvm::Constant*, 8> UsedArray;
1267 UsedArray.resize(List.size());
1268 for (unsigned i = 0, e = List.size(); i != e; ++i) {
1270 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(
1271 cast<llvm::Constant>(&*List[i]), CGM.Int8PtrTy);
1274 if (UsedArray.empty())
1276 llvm::ArrayType *ATy = llvm::ArrayType::get(CGM.Int8PtrTy, UsedArray.size());
1278 auto *GV = new llvm::GlobalVariable(
1279 CGM.getModule(), ATy, false, llvm::GlobalValue::AppendingLinkage,
1280 llvm::ConstantArray::get(ATy, UsedArray), Name);
1282 GV->setSection("llvm.metadata");
1285 void CodeGenModule::emitLLVMUsed() {
1286 emitUsed(*this, "llvm.used", LLVMUsed);
1287 emitUsed(*this, "llvm.compiler.used", LLVMCompilerUsed);
1290 void CodeGenModule::AppendLinkerOptions(StringRef Opts) {
1291 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opts);
1292 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
1295 void CodeGenModule::AddDetectMismatch(StringRef Name, StringRef Value) {
1296 llvm::SmallString<32> Opt;
1297 getTargetCodeGenInfo().getDetectMismatchOption(Name, Value, Opt);
1298 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt);
1299 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
1302 void CodeGenModule::AddDependentLib(StringRef Lib) {
1303 llvm::SmallString<24> Opt;
1304 getTargetCodeGenInfo().getDependentLibraryOption(Lib, Opt);
1305 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt);
1306 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
1309 /// \brief Add link options implied by the given module, including modules
1310 /// it depends on, using a postorder walk.
1311 static void addLinkOptionsPostorder(CodeGenModule &CGM, Module *Mod,
1312 SmallVectorImpl<llvm::MDNode *> &Metadata,
1313 llvm::SmallPtrSet<Module *, 16> &Visited) {
1314 // Import this module's parent.
1315 if (Mod->Parent && Visited.insert(Mod->Parent).second) {
1316 addLinkOptionsPostorder(CGM, Mod->Parent, Metadata, Visited);
1319 // Import this module's dependencies.
1320 for (unsigned I = Mod->Imports.size(); I > 0; --I) {
1321 if (Visited.insert(Mod->Imports[I - 1]).second)
1322 addLinkOptionsPostorder(CGM, Mod->Imports[I-1], Metadata, Visited);
1325 // Add linker options to link against the libraries/frameworks
1326 // described by this module.
1327 llvm::LLVMContext &Context = CGM.getLLVMContext();
1328 for (unsigned I = Mod->LinkLibraries.size(); I > 0; --I) {
1329 // Link against a framework. Frameworks are currently Darwin only, so we
1330 // don't to ask TargetCodeGenInfo for the spelling of the linker option.
1331 if (Mod->LinkLibraries[I-1].IsFramework) {
1332 llvm::Metadata *Args[2] = {
1333 llvm::MDString::get(Context, "-framework"),
1334 llvm::MDString::get(Context, Mod->LinkLibraries[I - 1].Library)};
1336 Metadata.push_back(llvm::MDNode::get(Context, Args));
1340 // Link against a library.
1341 llvm::SmallString<24> Opt;
1342 CGM.getTargetCodeGenInfo().getDependentLibraryOption(
1343 Mod->LinkLibraries[I-1].Library, Opt);
1344 auto *OptString = llvm::MDString::get(Context, Opt);
1345 Metadata.push_back(llvm::MDNode::get(Context, OptString));
1349 void CodeGenModule::EmitModuleLinkOptions() {
1350 // Collect the set of all of the modules we want to visit to emit link
1351 // options, which is essentially the imported modules and all of their
1352 // non-explicit child modules.
1353 llvm::SetVector<clang::Module *> LinkModules;
1354 llvm::SmallPtrSet<clang::Module *, 16> Visited;
1355 SmallVector<clang::Module *, 16> Stack;
1357 // Seed the stack with imported modules.
1358 for (Module *M : ImportedModules) {
1359 // Do not add any link flags when an implementation TU of a module imports
1360 // a header of that same module.
1361 if (M->getTopLevelModuleName() == getLangOpts().CurrentModule &&
1362 !getLangOpts().isCompilingModule())
1364 if (Visited.insert(M).second)
1368 // Find all of the modules to import, making a little effort to prune
1369 // non-leaf modules.
1370 while (!Stack.empty()) {
1371 clang::Module *Mod = Stack.pop_back_val();
1373 bool AnyChildren = false;
1375 // Visit the submodules of this module.
1376 for (clang::Module::submodule_iterator Sub = Mod->submodule_begin(),
1377 SubEnd = Mod->submodule_end();
1378 Sub != SubEnd; ++Sub) {
1379 // Skip explicit children; they need to be explicitly imported to be
1381 if ((*Sub)->IsExplicit)
1384 if (Visited.insert(*Sub).second) {
1385 Stack.push_back(*Sub);
1390 // We didn't find any children, so add this module to the list of
1391 // modules to link against.
1393 LinkModules.insert(Mod);
1397 // Add link options for all of the imported modules in reverse topological
1398 // order. We don't do anything to try to order import link flags with respect
1399 // to linker options inserted by things like #pragma comment().
1400 SmallVector<llvm::MDNode *, 16> MetadataArgs;
1402 for (Module *M : LinkModules)
1403 if (Visited.insert(M).second)
1404 addLinkOptionsPostorder(*this, M, MetadataArgs, Visited);
1405 std::reverse(MetadataArgs.begin(), MetadataArgs.end());
1406 LinkerOptionsMetadata.append(MetadataArgs.begin(), MetadataArgs.end());
1408 // Add the linker options metadata flag.
1409 auto *NMD = getModule().getOrInsertNamedMetadata("llvm.linker.options");
1410 for (auto *MD : LinkerOptionsMetadata)
1411 NMD->addOperand(MD);
1414 void CodeGenModule::EmitDeferred() {
1415 // Emit code for any potentially referenced deferred decls. Since a
1416 // previously unused static decl may become used during the generation of code
1417 // for a static function, iterate until no changes are made.
1419 if (!DeferredVTables.empty()) {
1420 EmitDeferredVTables();
1422 // Emitting a vtable doesn't directly cause more vtables to
1423 // become deferred, although it can cause functions to be
1424 // emitted that then need those vtables.
1425 assert(DeferredVTables.empty());
1428 // Stop if we're out of both deferred vtables and deferred declarations.
1429 if (DeferredDeclsToEmit.empty())
1432 // Grab the list of decls to emit. If EmitGlobalDefinition schedules more
1433 // work, it will not interfere with this.
1434 std::vector<GlobalDecl> CurDeclsToEmit;
1435 CurDeclsToEmit.swap(DeferredDeclsToEmit);
1437 for (GlobalDecl &D : CurDeclsToEmit) {
1438 // We should call GetAddrOfGlobal with IsForDefinition set to true in order
1439 // to get GlobalValue with exactly the type we need, not something that
1440 // might had been created for another decl with the same mangled name but
1442 llvm::GlobalValue *GV = dyn_cast<llvm::GlobalValue>(
1443 GetAddrOfGlobal(D, ForDefinition));
1445 // In case of different address spaces, we may still get a cast, even with
1446 // IsForDefinition equal to true. Query mangled names table to get
1449 GV = GetGlobalValue(getMangledName(D));
1451 // Make sure GetGlobalValue returned non-null.
1454 // Check to see if we've already emitted this. This is necessary
1455 // for a couple of reasons: first, decls can end up in the
1456 // deferred-decls queue multiple times, and second, decls can end
1457 // up with definitions in unusual ways (e.g. by an extern inline
1458 // function acquiring a strong function redefinition). Just
1459 // ignore these cases.
1460 if (!GV->isDeclaration())
1463 // Otherwise, emit the definition and move on to the next one.
1464 EmitGlobalDefinition(D, GV);
1466 // If we found out that we need to emit more decls, do that recursively.
1467 // This has the advantage that the decls are emitted in a DFS and related
1468 // ones are close together, which is convenient for testing.
1469 if (!DeferredVTables.empty() || !DeferredDeclsToEmit.empty()) {
1471 assert(DeferredVTables.empty() && DeferredDeclsToEmit.empty());
1476 void CodeGenModule::EmitVTablesOpportunistically() {
1477 // Try to emit external vtables as available_externally if they have emitted
1478 // all inlined virtual functions. It runs after EmitDeferred() and therefore
1479 // is not allowed to create new references to things that need to be emitted
1480 // lazily. Note that it also uses fact that we eagerly emitting RTTI.
1482 assert((OpportunisticVTables.empty() || shouldOpportunisticallyEmitVTables())
1483 && "Only emit opportunistic vtables with optimizations");
1485 for (const CXXRecordDecl *RD : OpportunisticVTables) {
1486 assert(getVTables().isVTableExternal(RD) &&
1487 "This queue should only contain external vtables");
1488 if (getCXXABI().canSpeculativelyEmitVTable(RD))
1489 VTables.GenerateClassData(RD);
1491 OpportunisticVTables.clear();
1494 void CodeGenModule::EmitGlobalAnnotations() {
1495 if (Annotations.empty())
1498 // Create a new global variable for the ConstantStruct in the Module.
1499 llvm::Constant *Array = llvm::ConstantArray::get(llvm::ArrayType::get(
1500 Annotations[0]->getType(), Annotations.size()), Annotations);
1501 auto *gv = new llvm::GlobalVariable(getModule(), Array->getType(), false,
1502 llvm::GlobalValue::AppendingLinkage,
1503 Array, "llvm.global.annotations");
1504 gv->setSection(AnnotationSection);
1507 llvm::Constant *CodeGenModule::EmitAnnotationString(StringRef Str) {
1508 llvm::Constant *&AStr = AnnotationStrings[Str];
1512 // Not found yet, create a new global.
1513 llvm::Constant *s = llvm::ConstantDataArray::getString(getLLVMContext(), Str);
1515 new llvm::GlobalVariable(getModule(), s->getType(), true,
1516 llvm::GlobalValue::PrivateLinkage, s, ".str");
1517 gv->setSection(AnnotationSection);
1518 gv->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
1523 llvm::Constant *CodeGenModule::EmitAnnotationUnit(SourceLocation Loc) {
1524 SourceManager &SM = getContext().getSourceManager();
1525 PresumedLoc PLoc = SM.getPresumedLoc(Loc);
1527 return EmitAnnotationString(PLoc.getFilename());
1528 return EmitAnnotationString(SM.getBufferName(Loc));
1531 llvm::Constant *CodeGenModule::EmitAnnotationLineNo(SourceLocation L) {
1532 SourceManager &SM = getContext().getSourceManager();
1533 PresumedLoc PLoc = SM.getPresumedLoc(L);
1534 unsigned LineNo = PLoc.isValid() ? PLoc.getLine() :
1535 SM.getExpansionLineNumber(L);
1536 return llvm::ConstantInt::get(Int32Ty, LineNo);
1539 llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV,
1540 const AnnotateAttr *AA,
1542 // Get the globals for file name, annotation, and the line number.
1543 llvm::Constant *AnnoGV = EmitAnnotationString(AA->getAnnotation()),
1544 *UnitGV = EmitAnnotationUnit(L),
1545 *LineNoCst = EmitAnnotationLineNo(L);
1547 // Create the ConstantStruct for the global annotation.
1548 llvm::Constant *Fields[4] = {
1549 llvm::ConstantExpr::getBitCast(GV, Int8PtrTy),
1550 llvm::ConstantExpr::getBitCast(AnnoGV, Int8PtrTy),
1551 llvm::ConstantExpr::getBitCast(UnitGV, Int8PtrTy),
1554 return llvm::ConstantStruct::getAnon(Fields);
1557 void CodeGenModule::AddGlobalAnnotations(const ValueDecl *D,
1558 llvm::GlobalValue *GV) {
1559 assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute");
1560 // Get the struct elements for these annotations.
1561 for (const auto *I : D->specific_attrs<AnnotateAttr>())
1562 Annotations.push_back(EmitAnnotateAttr(GV, I, D->getLocation()));
1565 bool CodeGenModule::isInSanitizerBlacklist(SanitizerMask Kind,
1567 SourceLocation Loc) const {
1568 const auto &SanitizerBL = getContext().getSanitizerBlacklist();
1569 // Blacklist by function name.
1570 if (SanitizerBL.isBlacklistedFunction(Kind, Fn->getName()))
1572 // Blacklist by location.
1574 return SanitizerBL.isBlacklistedLocation(Kind, Loc);
1575 // If location is unknown, this may be a compiler-generated function. Assume
1576 // it's located in the main file.
1577 auto &SM = Context.getSourceManager();
1578 if (const auto *MainFile = SM.getFileEntryForID(SM.getMainFileID())) {
1579 return SanitizerBL.isBlacklistedFile(Kind, MainFile->getName());
1584 bool CodeGenModule::isInSanitizerBlacklist(llvm::GlobalVariable *GV,
1585 SourceLocation Loc, QualType Ty,
1586 StringRef Category) const {
1587 // For now globals can be blacklisted only in ASan and KASan.
1588 const SanitizerMask EnabledAsanMask = LangOpts.Sanitize.Mask &
1589 (SanitizerKind::Address | SanitizerKind::KernelAddress | SanitizerKind::HWAddress);
1590 if (!EnabledAsanMask)
1592 const auto &SanitizerBL = getContext().getSanitizerBlacklist();
1593 if (SanitizerBL.isBlacklistedGlobal(EnabledAsanMask, GV->getName(), Category))
1595 if (SanitizerBL.isBlacklistedLocation(EnabledAsanMask, Loc, Category))
1597 // Check global type.
1599 // Drill down the array types: if global variable of a fixed type is
1600 // blacklisted, we also don't instrument arrays of them.
1601 while (auto AT = dyn_cast<ArrayType>(Ty.getTypePtr()))
1602 Ty = AT->getElementType();
1603 Ty = Ty.getCanonicalType().getUnqualifiedType();
1604 // We allow to blacklist only record types (classes, structs etc.)
1605 if (Ty->isRecordType()) {
1606 std::string TypeStr = Ty.getAsString(getContext().getPrintingPolicy());
1607 if (SanitizerBL.isBlacklistedType(EnabledAsanMask, TypeStr, Category))
1614 bool CodeGenModule::imbueXRayAttrs(llvm::Function *Fn, SourceLocation Loc,
1615 StringRef Category) const {
1616 if (!LangOpts.XRayInstrument)
1618 const auto &XRayFilter = getContext().getXRayFilter();
1619 using ImbueAttr = XRayFunctionFilter::ImbueAttribute;
1620 auto Attr = XRayFunctionFilter::ImbueAttribute::NONE;
1622 Attr = XRayFilter.shouldImbueLocation(Loc, Category);
1623 if (Attr == ImbueAttr::NONE)
1624 Attr = XRayFilter.shouldImbueFunction(Fn->getName());
1626 case ImbueAttr::NONE:
1628 case ImbueAttr::ALWAYS:
1629 Fn->addFnAttr("function-instrument", "xray-always");
1631 case ImbueAttr::ALWAYS_ARG1:
1632 Fn->addFnAttr("function-instrument", "xray-always");
1633 Fn->addFnAttr("xray-log-args", "1");
1635 case ImbueAttr::NEVER:
1636 Fn->addFnAttr("function-instrument", "xray-never");
1642 bool CodeGenModule::MustBeEmitted(const ValueDecl *Global) {
1643 // Never defer when EmitAllDecls is specified.
1644 if (LangOpts.EmitAllDecls)
1647 return getContext().DeclMustBeEmitted(Global);
1650 bool CodeGenModule::MayBeEmittedEagerly(const ValueDecl *Global) {
1651 if (const auto *FD = dyn_cast<FunctionDecl>(Global))
1652 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation)
1653 // Implicit template instantiations may change linkage if they are later
1654 // explicitly instantiated, so they should not be emitted eagerly.
1656 if (const auto *VD = dyn_cast<VarDecl>(Global))
1657 if (Context.getInlineVariableDefinitionKind(VD) ==
1658 ASTContext::InlineVariableDefinitionKind::WeakUnknown)
1659 // A definition of an inline constexpr static data member may change
1660 // linkage later if it's redeclared outside the class.
1662 // If OpenMP is enabled and threadprivates must be generated like TLS, delay
1663 // codegen for global variables, because they may be marked as threadprivate.
1664 if (LangOpts.OpenMP && LangOpts.OpenMPUseTLS &&
1665 getContext().getTargetInfo().isTLSSupported() && isa<VarDecl>(Global))
1671 ConstantAddress CodeGenModule::GetAddrOfUuidDescriptor(
1672 const CXXUuidofExpr* E) {
1673 // Sema has verified that IIDSource has a __declspec(uuid()), and that its
1675 StringRef Uuid = E->getUuidStr();
1676 std::string Name = "_GUID_" + Uuid.lower();
1677 std::replace(Name.begin(), Name.end(), '-', '_');
1679 // The UUID descriptor should be pointer aligned.
1680 CharUnits Alignment = CharUnits::fromQuantity(PointerAlignInBytes);
1682 // Look for an existing global.
1683 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name))
1684 return ConstantAddress(GV, Alignment);
1686 llvm::Constant *Init = EmitUuidofInitializer(Uuid);
1687 assert(Init && "failed to initialize as constant");
1689 auto *GV = new llvm::GlobalVariable(
1690 getModule(), Init->getType(),
1691 /*isConstant=*/true, llvm::GlobalValue::LinkOnceODRLinkage, Init, Name);
1692 if (supportsCOMDAT())
1693 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
1694 return ConstantAddress(GV, Alignment);
1697 ConstantAddress CodeGenModule::GetWeakRefReference(const ValueDecl *VD) {
1698 const AliasAttr *AA = VD->getAttr<AliasAttr>();
1699 assert(AA && "No alias?");
1701 CharUnits Alignment = getContext().getDeclAlign(VD);
1702 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(VD->getType());
1704 // See if there is already something with the target's name in the module.
1705 llvm::GlobalValue *Entry = GetGlobalValue(AA->getAliasee());
1707 unsigned AS = getContext().getTargetAddressSpace(VD->getType());
1708 auto Ptr = llvm::ConstantExpr::getBitCast(Entry, DeclTy->getPointerTo(AS));
1709 return ConstantAddress(Ptr, Alignment);
1712 llvm::Constant *Aliasee;
1713 if (isa<llvm::FunctionType>(DeclTy))
1714 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy,
1715 GlobalDecl(cast<FunctionDecl>(VD)),
1716 /*ForVTable=*/false);
1718 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(),
1719 llvm::PointerType::getUnqual(DeclTy),
1722 auto *F = cast<llvm::GlobalValue>(Aliasee);
1723 F->setLinkage(llvm::Function::ExternalWeakLinkage);
1724 WeakRefReferences.insert(F);
1726 return ConstantAddress(Aliasee, Alignment);
1729 void CodeGenModule::EmitGlobal(GlobalDecl GD) {
1730 const auto *Global = cast<ValueDecl>(GD.getDecl());
1732 // Weak references don't produce any output by themselves.
1733 if (Global->hasAttr<WeakRefAttr>())
1736 // If this is an alias definition (which otherwise looks like a declaration)
1738 if (Global->hasAttr<AliasAttr>())
1739 return EmitAliasDefinition(GD);
1741 // IFunc like an alias whose value is resolved at runtime by calling resolver.
1742 if (Global->hasAttr<IFuncAttr>())
1743 return emitIFuncDefinition(GD);
1745 // If this is CUDA, be selective about which declarations we emit.
1746 if (LangOpts.CUDA) {
1747 if (LangOpts.CUDAIsDevice) {
1748 if (!Global->hasAttr<CUDADeviceAttr>() &&
1749 !Global->hasAttr<CUDAGlobalAttr>() &&
1750 !Global->hasAttr<CUDAConstantAttr>() &&
1751 !Global->hasAttr<CUDASharedAttr>())
1754 // We need to emit host-side 'shadows' for all global
1755 // device-side variables because the CUDA runtime needs their
1756 // size and host-side address in order to provide access to
1757 // their device-side incarnations.
1759 // So device-only functions are the only things we skip.
1760 if (isa<FunctionDecl>(Global) && !Global->hasAttr<CUDAHostAttr>() &&
1761 Global->hasAttr<CUDADeviceAttr>())
1764 assert((isa<FunctionDecl>(Global) || isa<VarDecl>(Global)) &&
1765 "Expected Variable or Function");
1769 if (LangOpts.OpenMP) {
1770 // If this is OpenMP device, check if it is legal to emit this global
1772 if (OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(GD))
1774 if (auto *DRD = dyn_cast<OMPDeclareReductionDecl>(Global)) {
1775 if (MustBeEmitted(Global))
1776 EmitOMPDeclareReduction(DRD);
1781 // Ignore declarations, they will be emitted on their first use.
1782 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) {
1783 // Forward declarations are emitted lazily on first use.
1784 if (!FD->doesThisDeclarationHaveABody()) {
1785 if (!FD->doesDeclarationForceExternallyVisibleDefinition())
1788 StringRef MangledName = getMangledName(GD);
1790 // Compute the function info and LLVM type.
1791 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
1792 llvm::Type *Ty = getTypes().GetFunctionType(FI);
1794 GetOrCreateLLVMFunction(MangledName, Ty, GD, /*ForVTable=*/false,
1795 /*DontDefer=*/false);
1799 const auto *VD = cast<VarDecl>(Global);
1800 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global.");
1801 // We need to emit device-side global CUDA variables even if a
1802 // variable does not have a definition -- we still need to define
1803 // host-side shadow for it.
1804 bool MustEmitForCuda = LangOpts.CUDA && !LangOpts.CUDAIsDevice &&
1805 !VD->hasDefinition() &&
1806 (VD->hasAttr<CUDAConstantAttr>() ||
1807 VD->hasAttr<CUDADeviceAttr>());
1808 if (!MustEmitForCuda &&
1809 VD->isThisDeclarationADefinition() != VarDecl::Definition &&
1810 !Context.isMSStaticDataMemberInlineDefinition(VD)) {
1811 // If this declaration may have caused an inline variable definition to
1812 // change linkage, make sure that it's emitted.
1813 if (Context.getInlineVariableDefinitionKind(VD) ==
1814 ASTContext::InlineVariableDefinitionKind::Strong)
1815 GetAddrOfGlobalVar(VD);
1820 // Defer code generation to first use when possible, e.g. if this is an inline
1821 // function. If the global must always be emitted, do it eagerly if possible
1822 // to benefit from cache locality.
1823 if (MustBeEmitted(Global) && MayBeEmittedEagerly(Global)) {
1824 // Emit the definition if it can't be deferred.
1825 EmitGlobalDefinition(GD);
1829 // If we're deferring emission of a C++ variable with an
1830 // initializer, remember the order in which it appeared in the file.
1831 if (getLangOpts().CPlusPlus && isa<VarDecl>(Global) &&
1832 cast<VarDecl>(Global)->hasInit()) {
1833 DelayedCXXInitPosition[Global] = CXXGlobalInits.size();
1834 CXXGlobalInits.push_back(nullptr);
1837 StringRef MangledName = getMangledName(GD);
1838 if (GetGlobalValue(MangledName) != nullptr) {
1839 // The value has already been used and should therefore be emitted.
1840 addDeferredDeclToEmit(GD);
1841 } else if (MustBeEmitted(Global)) {
1842 // The value must be emitted, but cannot be emitted eagerly.
1843 assert(!MayBeEmittedEagerly(Global));
1844 addDeferredDeclToEmit(GD);
1846 // Otherwise, remember that we saw a deferred decl with this name. The
1847 // first use of the mangled name will cause it to move into
1848 // DeferredDeclsToEmit.
1849 DeferredDecls[MangledName] = GD;
1853 // Check if T is a class type with a destructor that's not dllimport.
1854 static bool HasNonDllImportDtor(QualType T) {
1855 if (const auto *RT = T->getBaseElementTypeUnsafe()->getAs<RecordType>())
1856 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()))
1857 if (RD->getDestructor() && !RD->getDestructor()->hasAttr<DLLImportAttr>())
1864 struct FunctionIsDirectlyRecursive :
1865 public RecursiveASTVisitor<FunctionIsDirectlyRecursive> {
1866 const StringRef Name;
1867 const Builtin::Context &BI;
1869 FunctionIsDirectlyRecursive(StringRef N, const Builtin::Context &C) :
1870 Name(N), BI(C), Result(false) {
1872 typedef RecursiveASTVisitor<FunctionIsDirectlyRecursive> Base;
1874 bool TraverseCallExpr(CallExpr *E) {
1875 const FunctionDecl *FD = E->getDirectCallee();
1878 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>();
1879 if (Attr && Name == Attr->getLabel()) {
1883 unsigned BuiltinID = FD->getBuiltinID();
1884 if (!BuiltinID || !BI.isLibFunction(BuiltinID))
1886 StringRef BuiltinName = BI.getName(BuiltinID);
1887 if (BuiltinName.startswith("__builtin_") &&
1888 Name == BuiltinName.slice(strlen("__builtin_"), StringRef::npos)) {
1896 // Make sure we're not referencing non-imported vars or functions.
1897 struct DLLImportFunctionVisitor
1898 : public RecursiveASTVisitor<DLLImportFunctionVisitor> {
1899 bool SafeToInline = true;
1901 bool shouldVisitImplicitCode() const { return true; }
1903 bool VisitVarDecl(VarDecl *VD) {
1904 if (VD->getTLSKind()) {
1905 // A thread-local variable cannot be imported.
1906 SafeToInline = false;
1907 return SafeToInline;
1910 // A variable definition might imply a destructor call.
1911 if (VD->isThisDeclarationADefinition())
1912 SafeToInline = !HasNonDllImportDtor(VD->getType());
1914 return SafeToInline;
1917 bool VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
1918 if (const auto *D = E->getTemporary()->getDestructor())
1919 SafeToInline = D->hasAttr<DLLImportAttr>();
1920 return SafeToInline;
1923 bool VisitDeclRefExpr(DeclRefExpr *E) {
1924 ValueDecl *VD = E->getDecl();
1925 if (isa<FunctionDecl>(VD))
1926 SafeToInline = VD->hasAttr<DLLImportAttr>();
1927 else if (VarDecl *V = dyn_cast<VarDecl>(VD))
1928 SafeToInline = !V->hasGlobalStorage() || V->hasAttr<DLLImportAttr>();
1929 return SafeToInline;
1932 bool VisitCXXConstructExpr(CXXConstructExpr *E) {
1933 SafeToInline = E->getConstructor()->hasAttr<DLLImportAttr>();
1934 return SafeToInline;
1937 bool VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
1938 CXXMethodDecl *M = E->getMethodDecl();
1940 // Call through a pointer to member function. This is safe to inline.
1941 SafeToInline = true;
1943 SafeToInline = M->hasAttr<DLLImportAttr>();
1945 return SafeToInline;
1948 bool VisitCXXDeleteExpr(CXXDeleteExpr *E) {
1949 SafeToInline = E->getOperatorDelete()->hasAttr<DLLImportAttr>();
1950 return SafeToInline;
1953 bool VisitCXXNewExpr(CXXNewExpr *E) {
1954 SafeToInline = E->getOperatorNew()->hasAttr<DLLImportAttr>();
1955 return SafeToInline;
1960 // isTriviallyRecursive - Check if this function calls another
1961 // decl that, because of the asm attribute or the other decl being a builtin,
1962 // ends up pointing to itself.
1964 CodeGenModule::isTriviallyRecursive(const FunctionDecl *FD) {
1966 if (getCXXABI().getMangleContext().shouldMangleDeclName(FD)) {
1967 // asm labels are a special kind of mangling we have to support.
1968 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>();
1971 Name = Attr->getLabel();
1973 Name = FD->getName();
1976 FunctionIsDirectlyRecursive Walker(Name, Context.BuiltinInfo);
1977 Walker.TraverseFunctionDecl(const_cast<FunctionDecl*>(FD));
1978 return Walker.Result;
1981 bool CodeGenModule::shouldEmitFunction(GlobalDecl GD) {
1982 if (getFunctionLinkage(GD) != llvm::Function::AvailableExternallyLinkage)
1984 const auto *F = cast<FunctionDecl>(GD.getDecl());
1985 if (CodeGenOpts.OptimizationLevel == 0 && !F->hasAttr<AlwaysInlineAttr>())
1988 if (F->hasAttr<DLLImportAttr>()) {
1989 // Check whether it would be safe to inline this dllimport function.
1990 DLLImportFunctionVisitor Visitor;
1991 Visitor.TraverseFunctionDecl(const_cast<FunctionDecl*>(F));
1992 if (!Visitor.SafeToInline)
1995 if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(F)) {
1996 // Implicit destructor invocations aren't captured in the AST, so the
1997 // check above can't see them. Check for them manually here.
1998 for (const Decl *Member : Dtor->getParent()->decls())
1999 if (isa<FieldDecl>(Member))
2000 if (HasNonDllImportDtor(cast<FieldDecl>(Member)->getType()))
2002 for (const CXXBaseSpecifier &B : Dtor->getParent()->bases())
2003 if (HasNonDllImportDtor(B.getType()))
2008 // PR9614. Avoid cases where the source code is lying to us. An available
2009 // externally function should have an equivalent function somewhere else,
2010 // but a function that calls itself is clearly not equivalent to the real
2012 // This happens in glibc's btowc and in some configure checks.
2013 return !isTriviallyRecursive(F);
2016 bool CodeGenModule::shouldOpportunisticallyEmitVTables() {
2017 return CodeGenOpts.OptimizationLevel > 0;
2020 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD, llvm::GlobalValue *GV) {
2021 const auto *D = cast<ValueDecl>(GD.getDecl());
2023 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(),
2024 Context.getSourceManager(),
2025 "Generating code for declaration");
2027 if (isa<FunctionDecl>(D)) {
2028 // At -O0, don't generate IR for functions with available_externally
2030 if (!shouldEmitFunction(GD))
2033 if (const auto *Method = dyn_cast<CXXMethodDecl>(D)) {
2034 // Make sure to emit the definition(s) before we emit the thunks.
2035 // This is necessary for the generation of certain thunks.
2036 if (const auto *CD = dyn_cast<CXXConstructorDecl>(Method))
2037 ABI->emitCXXStructor(CD, getFromCtorType(GD.getCtorType()));
2038 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(Method))
2039 ABI->emitCXXStructor(DD, getFromDtorType(GD.getDtorType()));
2041 EmitGlobalFunctionDefinition(GD, GV);
2043 if (Method->isVirtual())
2044 getVTables().EmitThunks(GD);
2049 return EmitGlobalFunctionDefinition(GD, GV);
2052 if (const auto *VD = dyn_cast<VarDecl>(D))
2053 return EmitGlobalVarDefinition(VD, !VD->hasDefinition());
2055 llvm_unreachable("Invalid argument to EmitGlobalDefinition()");
2058 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old,
2059 llvm::Function *NewFn);
2061 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the
2062 /// module, create and return an llvm Function with the specified type. If there
2063 /// is something in the module with the specified name, return it potentially
2064 /// bitcasted to the right type.
2066 /// If D is non-null, it specifies a decl that correspond to this. This is used
2067 /// to set the attributes on the function when it is first created.
2068 llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction(
2069 StringRef MangledName, llvm::Type *Ty, GlobalDecl GD, bool ForVTable,
2070 bool DontDefer, bool IsThunk, llvm::AttributeList ExtraAttrs,
2071 ForDefinition_t IsForDefinition) {
2072 const Decl *D = GD.getDecl();
2074 // Lookup the entry, lazily creating it if necessary.
2075 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
2077 if (WeakRefReferences.erase(Entry)) {
2078 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D);
2079 if (FD && !FD->hasAttr<WeakAttr>())
2080 Entry->setLinkage(llvm::Function::ExternalLinkage);
2083 // Handle dropped DLL attributes.
2084 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>())
2085 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
2087 // If there are two attempts to define the same mangled name, issue an
2089 if (IsForDefinition && !Entry->isDeclaration()) {
2091 // Check that GD is not yet in DiagnosedConflictingDefinitions is required
2092 // to make sure that we issue an error only once.
2093 if (lookupRepresentativeDecl(MangledName, OtherGD) &&
2094 (GD.getCanonicalDecl().getDecl() !=
2095 OtherGD.getCanonicalDecl().getDecl()) &&
2096 DiagnosedConflictingDefinitions.insert(GD).second) {
2097 getDiags().Report(D->getLocation(),
2098 diag::err_duplicate_mangled_name);
2099 getDiags().Report(OtherGD.getDecl()->getLocation(),
2100 diag::note_previous_definition);
2104 if ((isa<llvm::Function>(Entry) || isa<llvm::GlobalAlias>(Entry)) &&
2105 (Entry->getType()->getElementType() == Ty)) {
2109 // Make sure the result is of the correct type.
2110 // (If function is requested for a definition, we always need to create a new
2111 // function, not just return a bitcast.)
2112 if (!IsForDefinition)
2113 return llvm::ConstantExpr::getBitCast(Entry, Ty->getPointerTo());
2116 // This function doesn't have a complete type (for example, the return
2117 // type is an incomplete struct). Use a fake type instead, and make
2118 // sure not to try to set attributes.
2119 bool IsIncompleteFunction = false;
2121 llvm::FunctionType *FTy;
2122 if (isa<llvm::FunctionType>(Ty)) {
2123 FTy = cast<llvm::FunctionType>(Ty);
2125 FTy = llvm::FunctionType::get(VoidTy, false);
2126 IsIncompleteFunction = true;
2130 llvm::Function::Create(FTy, llvm::Function::ExternalLinkage,
2131 Entry ? StringRef() : MangledName, &getModule());
2133 // If we already created a function with the same mangled name (but different
2134 // type) before, take its name and add it to the list of functions to be
2135 // replaced with F at the end of CodeGen.
2137 // This happens if there is a prototype for a function (e.g. "int f()") and
2138 // then a definition of a different type (e.g. "int f(int x)").
2142 // This might be an implementation of a function without a prototype, in
2143 // which case, try to do special replacement of calls which match the new
2144 // prototype. The really key thing here is that we also potentially drop
2145 // arguments from the call site so as to make a direct call, which makes the
2146 // inliner happier and suppresses a number of optimizer warnings (!) about
2147 // dropping arguments.
2148 if (!Entry->use_empty()) {
2149 ReplaceUsesOfNonProtoTypeWithRealFunction(Entry, F);
2150 Entry->removeDeadConstantUsers();
2153 llvm::Constant *BC = llvm::ConstantExpr::getBitCast(
2154 F, Entry->getType()->getElementType()->getPointerTo());
2155 addGlobalValReplacement(Entry, BC);
2158 assert(F->getName() == MangledName && "name was uniqued!");
2160 SetFunctionAttributes(GD, F, IsIncompleteFunction, IsThunk,
2162 if (ExtraAttrs.hasAttributes(llvm::AttributeList::FunctionIndex)) {
2163 llvm::AttrBuilder B(ExtraAttrs, llvm::AttributeList::FunctionIndex);
2164 F->addAttributes(llvm::AttributeList::FunctionIndex, B);
2168 // All MSVC dtors other than the base dtor are linkonce_odr and delegate to
2169 // each other bottoming out with the base dtor. Therefore we emit non-base
2170 // dtors on usage, even if there is no dtor definition in the TU.
2171 if (D && isa<CXXDestructorDecl>(D) &&
2172 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D),
2174 addDeferredDeclToEmit(GD);
2176 // This is the first use or definition of a mangled name. If there is a
2177 // deferred decl with this name, remember that we need to emit it at the end
2179 auto DDI = DeferredDecls.find(MangledName);
2180 if (DDI != DeferredDecls.end()) {
2181 // Move the potentially referenced deferred decl to the
2182 // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we
2183 // don't need it anymore).
2184 addDeferredDeclToEmit(DDI->second);
2185 DeferredDecls.erase(DDI);
2187 // Otherwise, there are cases we have to worry about where we're
2188 // using a declaration for which we must emit a definition but where
2189 // we might not find a top-level definition:
2190 // - member functions defined inline in their classes
2191 // - friend functions defined inline in some class
2192 // - special member functions with implicit definitions
2193 // If we ever change our AST traversal to walk into class methods,
2194 // this will be unnecessary.
2196 // We also don't emit a definition for a function if it's going to be an
2197 // entry in a vtable, unless it's already marked as used.
2198 } else if (getLangOpts().CPlusPlus && D) {
2199 // Look for a declaration that's lexically in a record.
2200 for (const auto *FD = cast<FunctionDecl>(D)->getMostRecentDecl(); FD;
2201 FD = FD->getPreviousDecl()) {
2202 if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) {
2203 if (FD->doesThisDeclarationHaveABody()) {
2204 addDeferredDeclToEmit(GD.getWithDecl(FD));
2212 // Make sure the result is of the requested type.
2213 if (!IsIncompleteFunction) {
2214 assert(F->getType()->getElementType() == Ty);
2218 llvm::Type *PTy = llvm::PointerType::getUnqual(Ty);
2219 return llvm::ConstantExpr::getBitCast(F, PTy);
2222 /// GetAddrOfFunction - Return the address of the given function. If Ty is
2223 /// non-null, then this function will use the specified type if it has to
2224 /// create it (this occurs when we see a definition of the function).
2225 llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD,
2229 ForDefinition_t IsForDefinition) {
2230 // If there was no specific requested type, just convert it now.
2232 const auto *FD = cast<FunctionDecl>(GD.getDecl());
2233 auto CanonTy = Context.getCanonicalType(FD->getType());
2234 Ty = getTypes().ConvertFunctionType(CanonTy, FD);
2237 StringRef MangledName = getMangledName(GD);
2238 return GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable, DontDefer,
2239 /*IsThunk=*/false, llvm::AttributeList(),
2243 static const FunctionDecl *
2244 GetRuntimeFunctionDecl(ASTContext &C, StringRef Name) {
2245 TranslationUnitDecl *TUDecl = C.getTranslationUnitDecl();
2246 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl);
2248 IdentifierInfo &CII = C.Idents.get(Name);
2249 for (const auto &Result : DC->lookup(&CII))
2250 if (const auto FD = dyn_cast<FunctionDecl>(Result))
2253 if (!C.getLangOpts().CPlusPlus)
2256 // Demangle the premangled name from getTerminateFn()
2257 IdentifierInfo &CXXII =
2258 (Name == "_ZSt9terminatev" || Name == "\01?terminate@@YAXXZ")
2259 ? C.Idents.get("terminate")
2260 : C.Idents.get(Name);
2262 for (const auto &N : {"__cxxabiv1", "std"}) {
2263 IdentifierInfo &NS = C.Idents.get(N);
2264 for (const auto &Result : DC->lookup(&NS)) {
2265 NamespaceDecl *ND = dyn_cast<NamespaceDecl>(Result);
2266 if (auto LSD = dyn_cast<LinkageSpecDecl>(Result))
2267 for (const auto &Result : LSD->lookup(&NS))
2268 if ((ND = dyn_cast<NamespaceDecl>(Result)))
2272 for (const auto &Result : ND->lookup(&CXXII))
2273 if (const auto *FD = dyn_cast<FunctionDecl>(Result))
2281 /// CreateRuntimeFunction - Create a new runtime function with the specified
2284 CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy, StringRef Name,
2285 llvm::AttributeList ExtraAttrs,
2288 GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false,
2289 /*DontDefer=*/false, /*IsThunk=*/false,
2292 if (auto *F = dyn_cast<llvm::Function>(C)) {
2294 F->setCallingConv(getRuntimeCC());
2296 if (!Local && getTriple().isOSBinFormatCOFF() &&
2297 !getCodeGenOpts().LTOVisibilityPublicStd &&
2298 !getTriple().isWindowsGNUEnvironment()) {
2299 const FunctionDecl *FD = GetRuntimeFunctionDecl(Context, Name);
2300 if (!FD || FD->hasAttr<DLLImportAttr>()) {
2301 F->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
2302 F->setLinkage(llvm::GlobalValue::ExternalLinkage);
2311 /// CreateBuiltinFunction - Create a new builtin function with the specified
2314 CodeGenModule::CreateBuiltinFunction(llvm::FunctionType *FTy, StringRef Name,
2315 llvm::AttributeList ExtraAttrs) {
2317 GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false,
2318 /*DontDefer=*/false, /*IsThunk=*/false, ExtraAttrs);
2319 if (auto *F = dyn_cast<llvm::Function>(C))
2321 F->setCallingConv(getBuiltinCC());
2325 /// isTypeConstant - Determine whether an object of this type can be emitted
2328 /// If ExcludeCtor is true, the duration when the object's constructor runs
2329 /// will not be considered. The caller will need to verify that the object is
2330 /// not written to during its construction.
2331 bool CodeGenModule::isTypeConstant(QualType Ty, bool ExcludeCtor) {
2332 if (!Ty.isConstant(Context) && !Ty->isReferenceType())
2335 if (Context.getLangOpts().CPlusPlus) {
2336 if (const CXXRecordDecl *Record
2337 = Context.getBaseElementType(Ty)->getAsCXXRecordDecl())
2338 return ExcludeCtor && !Record->hasMutableFields() &&
2339 Record->hasTrivialDestructor();
2345 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module,
2346 /// create and return an llvm GlobalVariable with the specified type. If there
2347 /// is something in the module with the specified name, return it potentially
2348 /// bitcasted to the right type.
2350 /// If D is non-null, it specifies a decl that correspond to this. This is used
2351 /// to set the attributes on the global when it is first created.
2353 /// If IsForDefinition is true, it is guranteed that an actual global with
2354 /// type Ty will be returned, not conversion of a variable with the same
2355 /// mangled name but some other type.
2357 CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName,
2358 llvm::PointerType *Ty,
2360 ForDefinition_t IsForDefinition) {
2361 // Lookup the entry, lazily creating it if necessary.
2362 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
2364 if (WeakRefReferences.erase(Entry)) {
2365 if (D && !D->hasAttr<WeakAttr>())
2366 Entry->setLinkage(llvm::Function::ExternalLinkage);
2369 // Handle dropped DLL attributes.
2370 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>())
2371 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass);
2373 if (Entry->getType() == Ty)
2376 // If there are two attempts to define the same mangled name, issue an
2378 if (IsForDefinition && !Entry->isDeclaration()) {
2380 const VarDecl *OtherD;
2382 // Check that D is not yet in DiagnosedConflictingDefinitions is required
2383 // to make sure that we issue an error only once.
2384 if (D && lookupRepresentativeDecl(MangledName, OtherGD) &&
2385 (D->getCanonicalDecl() != OtherGD.getCanonicalDecl().getDecl()) &&
2386 (OtherD = dyn_cast<VarDecl>(OtherGD.getDecl())) &&
2387 OtherD->hasInit() &&
2388 DiagnosedConflictingDefinitions.insert(D).second) {
2389 getDiags().Report(D->getLocation(),
2390 diag::err_duplicate_mangled_name);
2391 getDiags().Report(OtherGD.getDecl()->getLocation(),
2392 diag::note_previous_definition);
2396 // Make sure the result is of the correct type.
2397 if (Entry->getType()->getAddressSpace() != Ty->getAddressSpace())
2398 return llvm::ConstantExpr::getAddrSpaceCast(Entry, Ty);
2400 // (If global is requested for a definition, we always need to create a new
2401 // global, not just return a bitcast.)
2402 if (!IsForDefinition)
2403 return llvm::ConstantExpr::getBitCast(Entry, Ty);
2406 auto AddrSpace = GetGlobalVarAddressSpace(D);
2407 auto TargetAddrSpace = getContext().getTargetAddressSpace(AddrSpace);
2409 auto *GV = new llvm::GlobalVariable(
2410 getModule(), Ty->getElementType(), false,
2411 llvm::GlobalValue::ExternalLinkage, nullptr, MangledName, nullptr,
2412 llvm::GlobalVariable::NotThreadLocal, TargetAddrSpace);
2414 // If we already created a global with the same mangled name (but different
2415 // type) before, take its name and remove it from its parent.
2417 GV->takeName(Entry);
2419 if (!Entry->use_empty()) {
2420 llvm::Constant *NewPtrForOldDecl =
2421 llvm::ConstantExpr::getBitCast(GV, Entry->getType());
2422 Entry->replaceAllUsesWith(NewPtrForOldDecl);
2425 Entry->eraseFromParent();
2428 // This is the first use or definition of a mangled name. If there is a
2429 // deferred decl with this name, remember that we need to emit it at the end
2431 auto DDI = DeferredDecls.find(MangledName);
2432 if (DDI != DeferredDecls.end()) {
2433 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit
2434 // list, and remove it from DeferredDecls (since we don't need it anymore).
2435 addDeferredDeclToEmit(DDI->second);
2436 DeferredDecls.erase(DDI);
2439 // Handle things which are present even on external declarations.
2441 // FIXME: This code is overly simple and should be merged with other global
2443 GV->setConstant(isTypeConstant(D->getType(), false));
2445 GV->setAlignment(getContext().getDeclAlign(D).getQuantity());
2447 setLinkageForGV(GV, D);
2448 setGlobalVisibility(GV, D, NotForDefinition);
2450 if (D->getTLSKind()) {
2451 if (D->getTLSKind() == VarDecl::TLS_Dynamic)
2452 CXXThreadLocals.push_back(D);
2456 // If required by the ABI, treat declarations of static data members with
2457 // inline initializers as definitions.
2458 if (getContext().isMSStaticDataMemberInlineDefinition(D)) {
2459 EmitGlobalVarDefinition(D);
2462 // Emit section information for extern variables.
2463 if (D->hasExternalStorage()) {
2464 if (const SectionAttr *SA = D->getAttr<SectionAttr>())
2465 GV->setSection(SA->getName());
2468 // Handle XCore specific ABI requirements.
2469 if (getTriple().getArch() == llvm::Triple::xcore &&
2470 D->getLanguageLinkage() == CLanguageLinkage &&
2471 D->getType().isConstant(Context) &&
2472 isExternallyVisible(D->getLinkageAndVisibility().getLinkage()))
2473 GV->setSection(".cp.rodata");
2475 // Check if we a have a const declaration with an initializer, we may be
2476 // able to emit it as available_externally to expose it's value to the
2478 if (Context.getLangOpts().CPlusPlus && GV->hasExternalLinkage() &&
2479 D->getType().isConstQualified() && !GV->hasInitializer() &&
2480 !D->hasDefinition() && D->hasInit() && !D->hasAttr<DLLImportAttr>()) {
2481 const auto *Record =
2482 Context.getBaseElementType(D->getType())->getAsCXXRecordDecl();
2483 bool HasMutableFields = Record && Record->hasMutableFields();
2484 if (!HasMutableFields) {
2485 const VarDecl *InitDecl;
2486 const Expr *InitExpr = D->getAnyInitializer(InitDecl);
2488 ConstantEmitter emitter(*this);
2489 llvm::Constant *Init = emitter.tryEmitForInitializer(*InitDecl);
2491 auto *InitType = Init->getType();
2492 if (GV->getType()->getElementType() != InitType) {
2493 // The type of the initializer does not match the definition.
2494 // This happens when an initializer has a different type from
2495 // the type of the global (because of padding at the end of a
2496 // structure for instance).
2497 GV->setName(StringRef());
2498 // Make a new global with the correct type, this is now guaranteed
2500 auto *NewGV = cast<llvm::GlobalVariable>(
2501 GetAddrOfGlobalVar(D, InitType, IsForDefinition));
2503 // Erase the old global, since it is no longer used.
2504 cast<llvm::GlobalValue>(GV)->eraseFromParent();
2507 GV->setInitializer(Init);
2508 GV->setConstant(true);
2509 GV->setLinkage(llvm::GlobalValue::AvailableExternallyLinkage);
2511 emitter.finalize(GV);
2519 D ? D->getType().getAddressSpace()
2520 : (LangOpts.OpenCL ? LangAS::opencl_global : LangAS::Default);
2521 assert(getContext().getTargetAddressSpace(ExpectedAS) ==
2522 Ty->getPointerAddressSpace());
2523 if (AddrSpace != ExpectedAS)
2524 return getTargetCodeGenInfo().performAddrSpaceCast(*this, GV, AddrSpace,
2531 CodeGenModule::GetAddrOfGlobal(GlobalDecl GD,
2532 ForDefinition_t IsForDefinition) {
2533 const Decl *D = GD.getDecl();
2534 if (isa<CXXConstructorDecl>(D))
2535 return getAddrOfCXXStructor(cast<CXXConstructorDecl>(D),
2536 getFromCtorType(GD.getCtorType()),
2537 /*FnInfo=*/nullptr, /*FnType=*/nullptr,
2538 /*DontDefer=*/false, IsForDefinition);
2539 else if (isa<CXXDestructorDecl>(D))
2540 return getAddrOfCXXStructor(cast<CXXDestructorDecl>(D),
2541 getFromDtorType(GD.getDtorType()),
2542 /*FnInfo=*/nullptr, /*FnType=*/nullptr,
2543 /*DontDefer=*/false, IsForDefinition);
2544 else if (isa<CXXMethodDecl>(D)) {
2545 auto FInfo = &getTypes().arrangeCXXMethodDeclaration(
2546 cast<CXXMethodDecl>(D));
2547 auto Ty = getTypes().GetFunctionType(*FInfo);
2548 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false,
2550 } else if (isa<FunctionDecl>(D)) {
2551 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
2552 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
2553 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false,
2556 return GetAddrOfGlobalVar(cast<VarDecl>(D), /*Ty=*/nullptr,
2560 llvm::GlobalVariable *
2561 CodeGenModule::CreateOrReplaceCXXRuntimeVariable(StringRef Name,
2563 llvm::GlobalValue::LinkageTypes Linkage) {
2564 llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name);
2565 llvm::GlobalVariable *OldGV = nullptr;
2568 // Check if the variable has the right type.
2569 if (GV->getType()->getElementType() == Ty)
2572 // Because C++ name mangling, the only way we can end up with an already
2573 // existing global with the same name is if it has been declared extern "C".
2574 assert(GV->isDeclaration() && "Declaration has wrong type!");
2578 // Create a new variable.
2579 GV = new llvm::GlobalVariable(getModule(), Ty, /*isConstant=*/true,
2580 Linkage, nullptr, Name);
2583 // Replace occurrences of the old variable if needed.
2584 GV->takeName(OldGV);
2586 if (!OldGV->use_empty()) {
2587 llvm::Constant *NewPtrForOldDecl =
2588 llvm::ConstantExpr::getBitCast(GV, OldGV->getType());
2589 OldGV->replaceAllUsesWith(NewPtrForOldDecl);
2592 OldGV->eraseFromParent();
2595 if (supportsCOMDAT() && GV->isWeakForLinker() &&
2596 !GV->hasAvailableExternallyLinkage())
2597 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
2602 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the
2603 /// given global variable. If Ty is non-null and if the global doesn't exist,
2604 /// then it will be created with the specified type instead of whatever the
2605 /// normal requested type would be. If IsForDefinition is true, it is guranteed
2606 /// that an actual global with type Ty will be returned, not conversion of a
2607 /// variable with the same mangled name but some other type.
2608 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D,
2610 ForDefinition_t IsForDefinition) {
2611 assert(D->hasGlobalStorage() && "Not a global variable");
2612 QualType ASTTy = D->getType();
2614 Ty = getTypes().ConvertTypeForMem(ASTTy);
2616 llvm::PointerType *PTy =
2617 llvm::PointerType::get(Ty, getContext().getTargetAddressSpace(ASTTy));
2619 StringRef MangledName = getMangledName(D);
2620 return GetOrCreateLLVMGlobal(MangledName, PTy, D, IsForDefinition);
2623 /// CreateRuntimeVariable - Create a new runtime global variable with the
2624 /// specified type and name.
2626 CodeGenModule::CreateRuntimeVariable(llvm::Type *Ty,
2628 return GetOrCreateLLVMGlobal(Name, llvm::PointerType::getUnqual(Ty), nullptr);
2631 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) {
2632 assert(!D->getInit() && "Cannot emit definite definitions here!");
2634 StringRef MangledName = getMangledName(D);
2635 llvm::GlobalValue *GV = GetGlobalValue(MangledName);
2637 // We already have a definition, not declaration, with the same mangled name.
2638 // Emitting of declaration is not required (and actually overwrites emitted
2640 if (GV && !GV->isDeclaration())
2643 // If we have not seen a reference to this variable yet, place it into the
2644 // deferred declarations table to be emitted if needed later.
2645 if (!MustBeEmitted(D) && !GV) {
2646 DeferredDecls[MangledName] = D;
2650 // The tentative definition is the only definition.
2651 EmitGlobalVarDefinition(D);
2654 CharUnits CodeGenModule::GetTargetTypeStoreSize(llvm::Type *Ty) const {
2655 return Context.toCharUnitsFromBits(
2656 getDataLayout().getTypeStoreSizeInBits(Ty));
2659 LangAS CodeGenModule::GetGlobalVarAddressSpace(const VarDecl *D) {
2660 LangAS AddrSpace = LangAS::Default;
2661 if (LangOpts.OpenCL) {
2662 AddrSpace = D ? D->getType().getAddressSpace() : LangAS::opencl_global;
2663 assert(AddrSpace == LangAS::opencl_global ||
2664 AddrSpace == LangAS::opencl_constant ||
2665 AddrSpace == LangAS::opencl_local ||
2666 AddrSpace >= LangAS::FirstTargetAddressSpace);
2670 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) {
2671 if (D && D->hasAttr<CUDAConstantAttr>())
2672 return LangAS::cuda_constant;
2673 else if (D && D->hasAttr<CUDASharedAttr>())
2674 return LangAS::cuda_shared;
2676 return LangAS::cuda_device;
2679 return getTargetCodeGenInfo().getGlobalVarAddressSpace(*this, D);
2682 template<typename SomeDecl>
2683 void CodeGenModule::MaybeHandleStaticInExternC(const SomeDecl *D,
2684 llvm::GlobalValue *GV) {
2685 if (!getLangOpts().CPlusPlus)
2688 // Must have 'used' attribute, or else inline assembly can't rely on
2689 // the name existing.
2690 if (!D->template hasAttr<UsedAttr>())
2693 // Must have internal linkage and an ordinary name.
2694 if (!D->getIdentifier() || D->getFormalLinkage() != InternalLinkage)
2697 // Must be in an extern "C" context. Entities declared directly within
2698 // a record are not extern "C" even if the record is in such a context.
2699 const SomeDecl *First = D->getFirstDecl();
2700 if (First->getDeclContext()->isRecord() || !First->isInExternCContext())
2703 // OK, this is an internal linkage entity inside an extern "C" linkage
2704 // specification. Make a note of that so we can give it the "expected"
2705 // mangled name if nothing else is using that name.
2706 std::pair<StaticExternCMap::iterator, bool> R =
2707 StaticExternCValues.insert(std::make_pair(D->getIdentifier(), GV));
2709 // If we have multiple internal linkage entities with the same name
2710 // in extern "C" regions, none of them gets that name.
2712 R.first->second = nullptr;
2715 static bool shouldBeInCOMDAT(CodeGenModule &CGM, const Decl &D) {
2716 if (!CGM.supportsCOMDAT())
2719 if (D.hasAttr<SelectAnyAttr>())
2723 if (auto *VD = dyn_cast<VarDecl>(&D))
2724 Linkage = CGM.getContext().GetGVALinkageForVariable(VD);
2726 Linkage = CGM.getContext().GetGVALinkageForFunction(cast<FunctionDecl>(&D));
2730 case GVA_AvailableExternally:
2731 case GVA_StrongExternal:
2733 case GVA_DiscardableODR:
2737 llvm_unreachable("No such linkage");
2740 void CodeGenModule::maybeSetTrivialComdat(const Decl &D,
2741 llvm::GlobalObject &GO) {
2742 if (!shouldBeInCOMDAT(*this, D))
2744 GO.setComdat(TheModule.getOrInsertComdat(GO.getName()));
2747 /// Pass IsTentative as true if you want to create a tentative definition.
2748 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
2750 // OpenCL global variables of sampler type are translated to function calls,
2751 // therefore no need to be translated.
2752 QualType ASTTy = D->getType();
2753 if (getLangOpts().OpenCL && ASTTy->isSamplerT())
2756 llvm::Constant *Init = nullptr;
2757 CXXRecordDecl *RD = ASTTy->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
2758 bool NeedsGlobalCtor = false;
2759 bool NeedsGlobalDtor = RD && !RD->hasTrivialDestructor();
2761 const VarDecl *InitDecl;
2762 const Expr *InitExpr = D->getAnyInitializer(InitDecl);
2764 Optional<ConstantEmitter> emitter;
2766 // CUDA E.2.4.1 "__shared__ variables cannot have an initialization
2767 // as part of their declaration." Sema has already checked for
2768 // error cases, so we just need to set Init to UndefValue.
2769 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice &&
2770 D->hasAttr<CUDASharedAttr>())
2771 Init = llvm::UndefValue::get(getTypes().ConvertType(ASTTy));
2772 else if (!InitExpr) {
2773 // This is a tentative definition; tentative definitions are
2774 // implicitly initialized with { 0 }.
2776 // Note that tentative definitions are only emitted at the end of
2777 // a translation unit, so they should never have incomplete
2778 // type. In addition, EmitTentativeDefinition makes sure that we
2779 // never attempt to emit a tentative definition if a real one
2780 // exists. A use may still exists, however, so we still may need
2782 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type");
2783 Init = EmitNullConstant(D->getType());
2785 initializedGlobalDecl = GlobalDecl(D);
2786 emitter.emplace(*this);
2787 Init = emitter->tryEmitForInitializer(*InitDecl);
2790 QualType T = InitExpr->getType();
2791 if (D->getType()->isReferenceType())
2794 if (getLangOpts().CPlusPlus) {
2795 Init = EmitNullConstant(T);
2796 NeedsGlobalCtor = true;
2798 ErrorUnsupported(D, "static initializer");
2799 Init = llvm::UndefValue::get(getTypes().ConvertType(T));
2802 // We don't need an initializer, so remove the entry for the delayed
2803 // initializer position (just in case this entry was delayed) if we
2804 // also don't need to register a destructor.
2805 if (getLangOpts().CPlusPlus && !NeedsGlobalDtor)
2806 DelayedCXXInitPosition.erase(D);
2810 llvm::Type* InitType = Init->getType();
2811 llvm::Constant *Entry =
2812 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative));
2814 // Strip off a bitcast if we got one back.
2815 if (auto *CE = dyn_cast<llvm::ConstantExpr>(Entry)) {
2816 assert(CE->getOpcode() == llvm::Instruction::BitCast ||
2817 CE->getOpcode() == llvm::Instruction::AddrSpaceCast ||
2818 // All zero index gep.
2819 CE->getOpcode() == llvm::Instruction::GetElementPtr);
2820 Entry = CE->getOperand(0);
2823 // Entry is now either a Function or GlobalVariable.
2824 auto *GV = dyn_cast<llvm::GlobalVariable>(Entry);
2826 // We have a definition after a declaration with the wrong type.
2827 // We must make a new GlobalVariable* and update everything that used OldGV
2828 // (a declaration or tentative definition) with the new GlobalVariable*
2829 // (which will be a definition).
2831 // This happens if there is a prototype for a global (e.g.
2832 // "extern int x[];") and then a definition of a different type (e.g.
2833 // "int x[10];"). This also happens when an initializer has a different type
2834 // from the type of the global (this happens with unions).
2835 if (!GV || GV->getType()->getElementType() != InitType ||
2836 GV->getType()->getAddressSpace() !=
2837 getContext().getTargetAddressSpace(GetGlobalVarAddressSpace(D))) {
2839 // Move the old entry aside so that we'll create a new one.
2840 Entry->setName(StringRef());
2842 // Make a new global with the correct type, this is now guaranteed to work.
2843 GV = cast<llvm::GlobalVariable>(
2844 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)));
2846 // Replace all uses of the old global with the new global
2847 llvm::Constant *NewPtrForOldDecl =
2848 llvm::ConstantExpr::getBitCast(GV, Entry->getType());
2849 Entry->replaceAllUsesWith(NewPtrForOldDecl);
2851 // Erase the old global, since it is no longer used.
2852 cast<llvm::GlobalValue>(Entry)->eraseFromParent();
2855 MaybeHandleStaticInExternC(D, GV);
2857 if (D->hasAttr<AnnotateAttr>())
2858 AddGlobalAnnotations(D, GV);
2860 // Set the llvm linkage type as appropriate.
2861 llvm::GlobalValue::LinkageTypes Linkage =
2862 getLLVMLinkageVarDefinition(D, GV->isConstant());
2864 // CUDA B.2.1 "The __device__ qualifier declares a variable that resides on
2865 // the device. [...]"
2866 // CUDA B.2.2 "The __constant__ qualifier, optionally used together with
2867 // __device__, declares a variable that: [...]
2868 // Is accessible from all the threads within the grid and from the host
2869 // through the runtime library (cudaGetSymbolAddress() / cudaGetSymbolSize()
2870 // / cudaMemcpyToSymbol() / cudaMemcpyFromSymbol())."
2871 if (GV && LangOpts.CUDA) {
2872 if (LangOpts.CUDAIsDevice) {
2873 if (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>())
2874 GV->setExternallyInitialized(true);
2876 // Host-side shadows of external declarations of device-side
2877 // global variables become internal definitions. These have to
2878 // be internal in order to prevent name conflicts with global
2879 // host variables with the same name in a different TUs.
2880 if (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>()) {
2881 Linkage = llvm::GlobalValue::InternalLinkage;
2883 // Shadow variables and their properties must be registered
2884 // with CUDA runtime.
2886 if (!D->hasDefinition())
2887 Flags |= CGCUDARuntime::ExternDeviceVar;
2888 if (D->hasAttr<CUDAConstantAttr>())
2889 Flags |= CGCUDARuntime::ConstantDeviceVar;
2890 getCUDARuntime().registerDeviceVar(*GV, Flags);
2891 } else if (D->hasAttr<CUDASharedAttr>())
2892 // __shared__ variables are odd. Shadows do get created, but
2893 // they are not registered with the CUDA runtime, so they
2894 // can't really be used to access their device-side
2895 // counterparts. It's not clear yet whether it's nvcc's bug or
2896 // a feature, but we've got to do the same for compatibility.
2897 Linkage = llvm::GlobalValue::InternalLinkage;
2901 GV->setInitializer(Init);
2902 if (emitter) emitter->finalize(GV);
2904 // If it is safe to mark the global 'constant', do so now.
2905 GV->setConstant(!NeedsGlobalCtor && !NeedsGlobalDtor &&
2906 isTypeConstant(D->getType(), true));
2908 // If it is in a read-only section, mark it 'constant'.
2909 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) {
2910 const ASTContext::SectionInfo &SI = Context.SectionInfos[SA->getName()];
2911 if ((SI.SectionFlags & ASTContext::PSF_Write) == 0)
2912 GV->setConstant(true);
2915 GV->setAlignment(getContext().getDeclAlign(D).getQuantity());
2918 // On Darwin, if the normal linkage of a C++ thread_local variable is
2919 // LinkOnce or Weak, we keep the normal linkage to prevent multiple
2920 // copies within a linkage unit; otherwise, the backing variable has
2921 // internal linkage and all accesses should just be calls to the
2922 // Itanium-specified entry point, which has the normal linkage of the
2923 // variable. This is to preserve the ability to change the implementation
2924 // behind the scenes.
2925 if (!D->isStaticLocal() && D->getTLSKind() == VarDecl::TLS_Dynamic &&
2926 Context.getTargetInfo().getTriple().isOSDarwin() &&
2927 !llvm::GlobalVariable::isLinkOnceLinkage(Linkage) &&
2928 !llvm::GlobalVariable::isWeakLinkage(Linkage))
2929 Linkage = llvm::GlobalValue::InternalLinkage;
2931 GV->setLinkage(Linkage);
2932 if (D->hasAttr<DLLImportAttr>())
2933 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass);
2934 else if (D->hasAttr<DLLExportAttr>())
2935 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass);
2937 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass);
2939 if (Linkage == llvm::GlobalVariable::CommonLinkage) {
2940 // common vars aren't constant even if declared const.
2941 GV->setConstant(false);
2942 // Tentative definition of global variables may be initialized with
2943 // non-zero null pointers. In this case they should have weak linkage
2944 // since common linkage must have zero initializer and must not have
2945 // explicit section therefore cannot have non-zero initial value.
2946 if (!GV->getInitializer()->isNullValue())
2947 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage);
2950 setNonAliasAttributes(D, GV);
2952 if (D->getTLSKind() && !GV->isThreadLocal()) {
2953 if (D->getTLSKind() == VarDecl::TLS_Dynamic)
2954 CXXThreadLocals.push_back(D);
2958 maybeSetTrivialComdat(*D, *GV);
2960 // Emit the initializer function if necessary.
2961 if (NeedsGlobalCtor || NeedsGlobalDtor)
2962 EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor);
2964 SanitizerMD->reportGlobalToASan(GV, *D, NeedsGlobalCtor);
2966 // Emit global variable debug information.
2967 if (CGDebugInfo *DI = getModuleDebugInfo())
2968 if (getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo)
2969 DI->EmitGlobalVariable(GV, D);
2972 static bool isVarDeclStrongDefinition(const ASTContext &Context,
2973 CodeGenModule &CGM, const VarDecl *D,
2975 // Don't give variables common linkage if -fno-common was specified unless it
2976 // was overridden by a NoCommon attribute.
2977 if ((NoCommon || D->hasAttr<NoCommonAttr>()) && !D->hasAttr<CommonAttr>())
2981 // A declaration of an identifier for an object that has file scope without
2982 // an initializer, and without a storage-class specifier or with the
2983 // storage-class specifier static, constitutes a tentative definition.
2984 if (D->getInit() || D->hasExternalStorage())
2987 // A variable cannot be both common and exist in a section.
2988 if (D->hasAttr<SectionAttr>())
2991 // A variable cannot be both common and exist in a section.
2992 // We dont try to determine which is the right section in the front-end.
2993 // If no specialized section name is applicable, it will resort to default.
2994 if (D->hasAttr<PragmaClangBSSSectionAttr>() ||
2995 D->hasAttr<PragmaClangDataSectionAttr>() ||
2996 D->hasAttr<PragmaClangRodataSectionAttr>())
2999 // Thread local vars aren't considered common linkage.
3000 if (D->getTLSKind())
3003 // Tentative definitions marked with WeakImportAttr are true definitions.
3004 if (D->hasAttr<WeakImportAttr>())
3007 // A variable cannot be both common and exist in a comdat.
3008 if (shouldBeInCOMDAT(CGM, *D))
3011 // Declarations with a required alignment do not have common linkage in MSVC
3013 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
3014 if (D->hasAttr<AlignedAttr>())
3016 QualType VarType = D->getType();
3017 if (Context.isAlignmentRequired(VarType))
3020 if (const auto *RT = VarType->getAs<RecordType>()) {
3021 const RecordDecl *RD = RT->getDecl();
3022 for (const FieldDecl *FD : RD->fields()) {
3023 if (FD->isBitField())
3025 if (FD->hasAttr<AlignedAttr>())
3027 if (Context.isAlignmentRequired(FD->getType()))
3036 llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageForDeclarator(
3037 const DeclaratorDecl *D, GVALinkage Linkage, bool IsConstantVariable) {
3038 if (Linkage == GVA_Internal)
3039 return llvm::Function::InternalLinkage;
3041 if (D->hasAttr<WeakAttr>()) {
3042 if (IsConstantVariable)
3043 return llvm::GlobalVariable::WeakODRLinkage;
3045 return llvm::GlobalVariable::WeakAnyLinkage;
3048 // We are guaranteed to have a strong definition somewhere else,
3049 // so we can use available_externally linkage.
3050 if (Linkage == GVA_AvailableExternally)
3051 return llvm::GlobalValue::AvailableExternallyLinkage;
3053 // Note that Apple's kernel linker doesn't support symbol
3054 // coalescing, so we need to avoid linkonce and weak linkages there.
3055 // Normally, this means we just map to internal, but for explicit
3056 // instantiations we'll map to external.
3058 // In C++, the compiler has to emit a definition in every translation unit
3059 // that references the function. We should use linkonce_odr because
3060 // a) if all references in this translation unit are optimized away, we
3061 // don't need to codegen it. b) if the function persists, it needs to be
3062 // merged with other definitions. c) C++ has the ODR, so we know the
3063 // definition is dependable.
3064 if (Linkage == GVA_DiscardableODR)
3065 return !Context.getLangOpts().AppleKext ? llvm::Function::LinkOnceODRLinkage
3066 : llvm::Function::InternalLinkage;
3068 // An explicit instantiation of a template has weak linkage, since
3069 // explicit instantiations can occur in multiple translation units
3070 // and must all be equivalent. However, we are not allowed to
3071 // throw away these explicit instantiations.
3073 // We don't currently support CUDA device code spread out across multiple TUs,
3074 // so say that CUDA templates are either external (for kernels) or internal.
3075 // This lets llvm perform aggressive inter-procedural optimizations.
3076 if (Linkage == GVA_StrongODR) {
3077 if (Context.getLangOpts().AppleKext)
3078 return llvm::Function::ExternalLinkage;
3079 if (Context.getLangOpts().CUDA && Context.getLangOpts().CUDAIsDevice)
3080 return D->hasAttr<CUDAGlobalAttr>() ? llvm::Function::ExternalLinkage
3081 : llvm::Function::InternalLinkage;
3082 return llvm::Function::WeakODRLinkage;
3085 // C++ doesn't have tentative definitions and thus cannot have common
3087 if (!getLangOpts().CPlusPlus && isa<VarDecl>(D) &&
3088 !isVarDeclStrongDefinition(Context, *this, cast<VarDecl>(D),
3089 CodeGenOpts.NoCommon))
3090 return llvm::GlobalVariable::CommonLinkage;
3092 // selectany symbols are externally visible, so use weak instead of
3093 // linkonce. MSVC optimizes away references to const selectany globals, so
3094 // all definitions should be the same and ODR linkage should be used.
3095 // http://msdn.microsoft.com/en-us/library/5tkz6s71.aspx
3096 if (D->hasAttr<SelectAnyAttr>())
3097 return llvm::GlobalVariable::WeakODRLinkage;
3099 // Otherwise, we have strong external linkage.
3100 assert(Linkage == GVA_StrongExternal);
3101 return llvm::GlobalVariable::ExternalLinkage;
3104 llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageVarDefinition(
3105 const VarDecl *VD, bool IsConstant) {
3106 GVALinkage Linkage = getContext().GetGVALinkageForVariable(VD);
3107 return getLLVMLinkageForDeclarator(VD, Linkage, IsConstant);
3110 /// Replace the uses of a function that was declared with a non-proto type.
3111 /// We want to silently drop extra arguments from call sites
3112 static void replaceUsesOfNonProtoConstant(llvm::Constant *old,
3113 llvm::Function *newFn) {
3115 if (old->use_empty()) return;
3117 llvm::Type *newRetTy = newFn->getReturnType();
3118 SmallVector<llvm::Value*, 4> newArgs;
3119 SmallVector<llvm::OperandBundleDef, 1> newBundles;
3121 for (llvm::Value::use_iterator ui = old->use_begin(), ue = old->use_end();
3123 llvm::Value::use_iterator use = ui++; // Increment before the use is erased.
3124 llvm::User *user = use->getUser();
3126 // Recognize and replace uses of bitcasts. Most calls to
3127 // unprototyped functions will use bitcasts.
3128 if (auto *bitcast = dyn_cast<llvm::ConstantExpr>(user)) {
3129 if (bitcast->getOpcode() == llvm::Instruction::BitCast)
3130 replaceUsesOfNonProtoConstant(bitcast, newFn);
3134 // Recognize calls to the function.
3135 llvm::CallSite callSite(user);
3136 if (!callSite) continue;
3137 if (!callSite.isCallee(&*use)) continue;
3139 // If the return types don't match exactly, then we can't
3140 // transform this call unless it's dead.
3141 if (callSite->getType() != newRetTy && !callSite->use_empty())
3144 // Get the call site's attribute list.
3145 SmallVector<llvm::AttributeSet, 8> newArgAttrs;
3146 llvm::AttributeList oldAttrs = callSite.getAttributes();
3148 // If the function was passed too few arguments, don't transform.
3149 unsigned newNumArgs = newFn->arg_size();
3150 if (callSite.arg_size() < newNumArgs) continue;
3152 // If extra arguments were passed, we silently drop them.
3153 // If any of the types mismatch, we don't transform.
3155 bool dontTransform = false;
3156 for (llvm::Argument &A : newFn->args()) {
3157 if (callSite.getArgument(argNo)->getType() != A.getType()) {
3158 dontTransform = true;
3162 // Add any parameter attributes.
3163 newArgAttrs.push_back(oldAttrs.getParamAttributes(argNo));
3169 // Okay, we can transform this. Create the new call instruction and copy
3170 // over the required information.
3171 newArgs.append(callSite.arg_begin(), callSite.arg_begin() + argNo);
3173 // Copy over any operand bundles.
3174 callSite.getOperandBundlesAsDefs(newBundles);
3176 llvm::CallSite newCall;
3177 if (callSite.isCall()) {
3178 newCall = llvm::CallInst::Create(newFn, newArgs, newBundles, "",
3179 callSite.getInstruction());
3181 auto *oldInvoke = cast<llvm::InvokeInst>(callSite.getInstruction());
3182 newCall = llvm::InvokeInst::Create(newFn,
3183 oldInvoke->getNormalDest(),
3184 oldInvoke->getUnwindDest(),
3185 newArgs, newBundles, "",
3186 callSite.getInstruction());
3188 newArgs.clear(); // for the next iteration
3190 if (!newCall->getType()->isVoidTy())
3191 newCall->takeName(callSite.getInstruction());
3192 newCall.setAttributes(llvm::AttributeList::get(
3193 newFn->getContext(), oldAttrs.getFnAttributes(),
3194 oldAttrs.getRetAttributes(), newArgAttrs));
3195 newCall.setCallingConv(callSite.getCallingConv());
3197 // Finally, remove the old call, replacing any uses with the new one.
3198 if (!callSite->use_empty())
3199 callSite->replaceAllUsesWith(newCall.getInstruction());
3201 // Copy debug location attached to CI.
3202 if (callSite->getDebugLoc())
3203 newCall->setDebugLoc(callSite->getDebugLoc());
3205 callSite->eraseFromParent();
3209 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we
3210 /// implement a function with no prototype, e.g. "int foo() {}". If there are
3211 /// existing call uses of the old function in the module, this adjusts them to
3212 /// call the new function directly.
3214 /// This is not just a cleanup: the always_inline pass requires direct calls to
3215 /// functions to be able to inline them. If there is a bitcast in the way, it
3216 /// won't inline them. Instcombine normally deletes these calls, but it isn't
3218 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old,
3219 llvm::Function *NewFn) {
3220 // If we're redefining a global as a function, don't transform it.
3221 if (!isa<llvm::Function>(Old)) return;
3223 replaceUsesOfNonProtoConstant(Old, NewFn);
3226 void CodeGenModule::HandleCXXStaticMemberVarInstantiation(VarDecl *VD) {
3227 auto DK = VD->isThisDeclarationADefinition();
3228 if (DK == VarDecl::Definition && VD->hasAttr<DLLImportAttr>())
3231 TemplateSpecializationKind TSK = VD->getTemplateSpecializationKind();
3232 // If we have a definition, this might be a deferred decl. If the
3233 // instantiation is explicit, make sure we emit it at the end.
3234 if (VD->getDefinition() && TSK == TSK_ExplicitInstantiationDefinition)
3235 GetAddrOfGlobalVar(VD);
3237 EmitTopLevelDecl(VD);
3240 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD,
3241 llvm::GlobalValue *GV) {
3242 const auto *D = cast<FunctionDecl>(GD.getDecl());
3244 // Compute the function info and LLVM type.
3245 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD);
3246 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI);
3248 // Get or create the prototype for the function.
3249 if (!GV || (GV->getType()->getElementType() != Ty))
3250 GV = cast<llvm::GlobalValue>(GetAddrOfFunction(GD, Ty, /*ForVTable=*/false,
3255 if (!GV->isDeclaration())
3258 // We need to set linkage and visibility on the function before
3259 // generating code for it because various parts of IR generation
3260 // want to propagate this information down (e.g. to local static
3262 auto *Fn = cast<llvm::Function>(GV);
3263 setFunctionLinkage(GD, Fn);
3264 setFunctionDLLStorageClass(GD, Fn);
3266 // FIXME: this is redundant with part of setFunctionDefinitionAttributes
3267 setGlobalVisibility(Fn, D, ForDefinition);
3269 MaybeHandleStaticInExternC(D, Fn);
3271 maybeSetTrivialComdat(*D, *Fn);
3273 CodeGenFunction(*this).GenerateCode(D, Fn, FI);
3275 setFunctionDefinitionAttributes(D, Fn);
3276 SetLLVMFunctionAttributesForDefinition(D, Fn);
3278 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>())
3279 AddGlobalCtor(Fn, CA->getPriority());
3280 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>())
3281 AddGlobalDtor(Fn, DA->getPriority());
3282 if (D->hasAttr<AnnotateAttr>())
3283 AddGlobalAnnotations(D, Fn);
3286 void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) {
3287 const auto *D = cast<ValueDecl>(GD.getDecl());
3288 const AliasAttr *AA = D->getAttr<AliasAttr>();
3289 assert(AA && "Not an alias?");
3291 StringRef MangledName = getMangledName(GD);
3293 if (AA->getAliasee() == MangledName) {
3294 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0;
3298 // If there is a definition in the module, then it wins over the alias.
3299 // This is dubious, but allow it to be safe. Just ignore the alias.
3300 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
3301 if (Entry && !Entry->isDeclaration())
3304 Aliases.push_back(GD);
3306 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType());
3308 // Create a reference to the named value. This ensures that it is emitted
3309 // if a deferred decl.
3310 llvm::Constant *Aliasee;
3311 if (isa<llvm::FunctionType>(DeclTy))
3312 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GD,
3313 /*ForVTable=*/false);
3315 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(),
3316 llvm::PointerType::getUnqual(DeclTy),
3319 // Create the new alias itself, but don't set a name yet.
3320 auto *GA = llvm::GlobalAlias::create(
3321 DeclTy, 0, llvm::Function::ExternalLinkage, "", Aliasee, &getModule());
3324 if (GA->getAliasee() == Entry) {
3325 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0;
3329 assert(Entry->isDeclaration());
3331 // If there is a declaration in the module, then we had an extern followed
3332 // by the alias, as in:
3333 // extern int test6();
3335 // int test6() __attribute__((alias("test7")));
3337 // Remove it and replace uses of it with the alias.
3338 GA->takeName(Entry);
3340 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA,
3342 Entry->eraseFromParent();
3344 GA->setName(MangledName);
3347 // Set attributes which are particular to an alias; this is a
3348 // specialization of the attributes which may be set on a global
3349 // variable/function.
3350 if (D->hasAttr<WeakAttr>() || D->hasAttr<WeakRefAttr>() ||
3351 D->isWeakImported()) {
3352 GA->setLinkage(llvm::Function::WeakAnyLinkage);
3355 if (const auto *VD = dyn_cast<VarDecl>(D))
3356 if (VD->getTLSKind())
3357 setTLSMode(GA, *VD);
3359 setAliasAttributes(D, GA);
3362 void CodeGenModule::emitIFuncDefinition(GlobalDecl GD) {
3363 const auto *D = cast<ValueDecl>(GD.getDecl());
3364 const IFuncAttr *IFA = D->getAttr<IFuncAttr>();
3365 assert(IFA && "Not an ifunc?");
3367 StringRef MangledName = getMangledName(GD);
3369 if (IFA->getResolver() == MangledName) {
3370 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1;
3374 // Report an error if some definition overrides ifunc.
3375 llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
3376 if (Entry && !Entry->isDeclaration()) {
3378 if (lookupRepresentativeDecl(MangledName, OtherGD) &&
3379 DiagnosedConflictingDefinitions.insert(GD).second) {
3380 Diags.Report(D->getLocation(), diag::err_duplicate_mangled_name);
3381 Diags.Report(OtherGD.getDecl()->getLocation(),
3382 diag::note_previous_definition);
3387 Aliases.push_back(GD);
3389 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType());
3390 llvm::Constant *Resolver =
3391 GetOrCreateLLVMFunction(IFA->getResolver(), DeclTy, GD,
3392 /*ForVTable=*/false);
3393 llvm::GlobalIFunc *GIF =
3394 llvm::GlobalIFunc::create(DeclTy, 0, llvm::Function::ExternalLinkage,
3395 "", Resolver, &getModule());
3397 if (GIF->getResolver() == Entry) {
3398 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1;
3401 assert(Entry->isDeclaration());
3403 // If there is a declaration in the module, then we had an extern followed
3404 // by the ifunc, as in:
3405 // extern int test();
3407 // int test() __attribute__((ifunc("resolver")));
3409 // Remove it and replace uses of it with the ifunc.
3410 GIF->takeName(Entry);
3412 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GIF,
3414 Entry->eraseFromParent();
3416 GIF->setName(MangledName);
3418 SetCommonAttributes(D, GIF);
3421 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID,
3422 ArrayRef<llvm::Type*> Tys) {
3423 return llvm::Intrinsic::getDeclaration(&getModule(), (llvm::Intrinsic::ID)IID,
3427 static llvm::StringMapEntry<llvm::GlobalVariable *> &
3428 GetConstantCFStringEntry(llvm::StringMap<llvm::GlobalVariable *> &Map,
3429 const StringLiteral *Literal, bool TargetIsLSB,
3430 bool &IsUTF16, unsigned &StringLength) {
3431 StringRef String = Literal->getString();
3432 unsigned NumBytes = String.size();
3434 // Check for simple case.
3435 if (!Literal->containsNonAsciiOrNull()) {
3436 StringLength = NumBytes;
3437 return *Map.insert(std::make_pair(String, nullptr)).first;
3440 // Otherwise, convert the UTF8 literals into a string of shorts.
3443 SmallVector<llvm::UTF16, 128> ToBuf(NumBytes + 1); // +1 for ending nulls.
3444 const llvm::UTF8 *FromPtr = (const llvm::UTF8 *)String.data();
3445 llvm::UTF16 *ToPtr = &ToBuf[0];
3447 (void)llvm::ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, &ToPtr,
3448 ToPtr + NumBytes, llvm::strictConversion);
3450 // ConvertUTF8toUTF16 returns the length in ToPtr.
3451 StringLength = ToPtr - &ToBuf[0];
3453 // Add an explicit null.
3455 return *Map.insert(std::make_pair(
3456 StringRef(reinterpret_cast<const char *>(ToBuf.data()),
3457 (StringLength + 1) * 2),
3462 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) {
3463 unsigned StringLength = 0;
3464 bool isUTF16 = false;
3465 llvm::StringMapEntry<llvm::GlobalVariable *> &Entry =
3466 GetConstantCFStringEntry(CFConstantStringMap, Literal,
3467 getDataLayout().isLittleEndian(), isUTF16,
3470 if (auto *C = Entry.second)
3471 return ConstantAddress(C, CharUnits::fromQuantity(C->getAlignment()));
3473 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty);
3474 llvm::Constant *Zeros[] = { Zero, Zero };
3476 // If we don't already have it, get __CFConstantStringClassReference.
3477 if (!CFConstantStringClassRef) {
3478 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy);
3479 Ty = llvm::ArrayType::get(Ty, 0);
3480 llvm::Constant *GV =
3481 CreateRuntimeVariable(Ty, "__CFConstantStringClassReference");
3483 if (getTriple().isOSBinFormatCOFF()) {
3484 IdentifierInfo &II = getContext().Idents.get(GV->getName());
3485 TranslationUnitDecl *TUDecl = getContext().getTranslationUnitDecl();
3486 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl);
3487 llvm::GlobalValue *CGV = cast<llvm::GlobalValue>(GV);
3489 const VarDecl *VD = nullptr;
3490 for (const auto &Result : DC->lookup(&II))
3491 if ((VD = dyn_cast<VarDecl>(Result)))
3494 if (!VD || !VD->hasAttr<DLLExportAttr>()) {
3495 CGV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
3496 CGV->setLinkage(llvm::GlobalValue::ExternalLinkage);
3498 CGV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
3499 CGV->setLinkage(llvm::GlobalValue::ExternalLinkage);
3503 // Decay array -> ptr
3504 CFConstantStringClassRef =
3505 llvm::ConstantExpr::getGetElementPtr(Ty, GV, Zeros);
3508 QualType CFTy = getContext().getCFConstantStringType();
3510 auto *STy = cast<llvm::StructType>(getTypes().ConvertType(CFTy));
3512 ConstantInitBuilder Builder(*this);
3513 auto Fields = Builder.beginStruct(STy);
3516 Fields.add(cast<llvm::ConstantExpr>(CFConstantStringClassRef));
3519 Fields.addInt(IntTy, isUTF16 ? 0x07d0 : 0x07C8);
3522 llvm::Constant *C = nullptr;
3524 auto Arr = llvm::makeArrayRef(
3525 reinterpret_cast<uint16_t *>(const_cast<char *>(Entry.first().data())),
3526 Entry.first().size() / 2);
3527 C = llvm::ConstantDataArray::get(VMContext, Arr);
3529 C = llvm::ConstantDataArray::getString(VMContext, Entry.first());
3532 // Note: -fwritable-strings doesn't make the backing store strings of
3533 // CFStrings writable. (See <rdar://problem/10657500>)
3535 new llvm::GlobalVariable(getModule(), C->getType(), /*isConstant=*/true,
3536 llvm::GlobalValue::PrivateLinkage, C, ".str");
3537 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3538 // Don't enforce the target's minimum global alignment, since the only use
3539 // of the string is via this class initializer.
3540 CharUnits Align = isUTF16
3541 ? getContext().getTypeAlignInChars(getContext().ShortTy)
3542 : getContext().getTypeAlignInChars(getContext().CharTy);
3543 GV->setAlignment(Align.getQuantity());
3545 // FIXME: We set the section explicitly to avoid a bug in ld64 224.1.
3546 // Without it LLVM can merge the string with a non unnamed_addr one during
3547 // LTO. Doing that changes the section it ends in, which surprises ld64.
3548 if (getTriple().isOSBinFormatMachO())
3549 GV->setSection(isUTF16 ? "__TEXT,__ustring"
3550 : "__TEXT,__cstring,cstring_literals");
3553 llvm::Constant *Str =
3554 llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV, Zeros);
3557 // Cast the UTF16 string to the correct type.
3558 Str = llvm::ConstantExpr::getBitCast(Str, Int8PtrTy);
3562 auto Ty = getTypes().ConvertType(getContext().LongTy);
3563 Fields.addInt(cast<llvm::IntegerType>(Ty), StringLength);
3565 CharUnits Alignment = getPointerAlign();
3568 GV = Fields.finishAndCreateGlobal("_unnamed_cfstring_", Alignment,
3569 /*isConstant=*/false,
3570 llvm::GlobalVariable::PrivateLinkage);
3571 switch (getTriple().getObjectFormat()) {
3572 case llvm::Triple::UnknownObjectFormat:
3573 llvm_unreachable("unknown file format");
3574 case llvm::Triple::COFF:
3575 case llvm::Triple::ELF:
3576 case llvm::Triple::Wasm:
3577 GV->setSection("cfstring");
3579 case llvm::Triple::MachO:
3580 GV->setSection("__DATA,__cfstring");
3585 return ConstantAddress(GV, Alignment);
3588 bool CodeGenModule::getExpressionLocationsEnabled() const {
3589 return !CodeGenOpts.EmitCodeView || CodeGenOpts.DebugColumnInfo;
3592 QualType CodeGenModule::getObjCFastEnumerationStateType() {
3593 if (ObjCFastEnumerationStateType.isNull()) {
3594 RecordDecl *D = Context.buildImplicitRecord("__objcFastEnumerationState");
3595 D->startDefinition();
3597 QualType FieldTypes[] = {
3598 Context.UnsignedLongTy,
3599 Context.getPointerType(Context.getObjCIdType()),
3600 Context.getPointerType(Context.UnsignedLongTy),
3601 Context.getConstantArrayType(Context.UnsignedLongTy,
3602 llvm::APInt(32, 5), ArrayType::Normal, 0)
3605 for (size_t i = 0; i < 4; ++i) {
3606 FieldDecl *Field = FieldDecl::Create(Context,
3609 SourceLocation(), nullptr,
3610 FieldTypes[i], /*TInfo=*/nullptr,
3611 /*BitWidth=*/nullptr,
3614 Field->setAccess(AS_public);
3618 D->completeDefinition();
3619 ObjCFastEnumerationStateType = Context.getTagDeclType(D);
3622 return ObjCFastEnumerationStateType;
3626 CodeGenModule::GetConstantArrayFromStringLiteral(const StringLiteral *E) {
3627 assert(!E->getType()->isPointerType() && "Strings are always arrays");
3629 // Don't emit it as the address of the string, emit the string data itself
3630 // as an inline array.
3631 if (E->getCharByteWidth() == 1) {
3632 SmallString<64> Str(E->getString());
3634 // Resize the string to the right size, which is indicated by its type.
3635 const ConstantArrayType *CAT = Context.getAsConstantArrayType(E->getType());
3636 Str.resize(CAT->getSize().getZExtValue());
3637 return llvm::ConstantDataArray::getString(VMContext, Str, false);
3640 auto *AType = cast<llvm::ArrayType>(getTypes().ConvertType(E->getType()));
3641 llvm::Type *ElemTy = AType->getElementType();
3642 unsigned NumElements = AType->getNumElements();
3644 // Wide strings have either 2-byte or 4-byte elements.
3645 if (ElemTy->getPrimitiveSizeInBits() == 16) {
3646 SmallVector<uint16_t, 32> Elements;
3647 Elements.reserve(NumElements);
3649 for(unsigned i = 0, e = E->getLength(); i != e; ++i)
3650 Elements.push_back(E->getCodeUnit(i));
3651 Elements.resize(NumElements);
3652 return llvm::ConstantDataArray::get(VMContext, Elements);
3655 assert(ElemTy->getPrimitiveSizeInBits() == 32);
3656 SmallVector<uint32_t, 32> Elements;
3657 Elements.reserve(NumElements);
3659 for(unsigned i = 0, e = E->getLength(); i != e; ++i)
3660 Elements.push_back(E->getCodeUnit(i));
3661 Elements.resize(NumElements);
3662 return llvm::ConstantDataArray::get(VMContext, Elements);
3665 static llvm::GlobalVariable *
3666 GenerateStringLiteral(llvm::Constant *C, llvm::GlobalValue::LinkageTypes LT,
3667 CodeGenModule &CGM, StringRef GlobalName,
3668 CharUnits Alignment) {
3669 // OpenCL v1.2 s6.5.3: a string literal is in the constant address space.
3670 unsigned AddrSpace = 0;
3671 if (CGM.getLangOpts().OpenCL)
3672 AddrSpace = CGM.getContext().getTargetAddressSpace(LangAS::opencl_constant);
3674 llvm::Module &M = CGM.getModule();
3675 // Create a global variable for this string
3676 auto *GV = new llvm::GlobalVariable(
3677 M, C->getType(), !CGM.getLangOpts().WritableStrings, LT, C, GlobalName,
3678 nullptr, llvm::GlobalVariable::NotThreadLocal, AddrSpace);
3679 GV->setAlignment(Alignment.getQuantity());
3680 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
3681 if (GV->isWeakForLinker()) {
3682 assert(CGM.supportsCOMDAT() && "Only COFF uses weak string literals");
3683 GV->setComdat(M.getOrInsertComdat(GV->getName()));
3689 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a
3690 /// constant array for the given string literal.
3692 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S,
3694 CharUnits Alignment = getContext().getAlignOfGlobalVarInChars(S->getType());
3696 llvm::Constant *C = GetConstantArrayFromStringLiteral(S);
3697 llvm::GlobalVariable **Entry = nullptr;
3698 if (!LangOpts.WritableStrings) {
3699 Entry = &ConstantStringMap[C];
3700 if (auto GV = *Entry) {
3701 if (Alignment.getQuantity() > GV->getAlignment())
3702 GV->setAlignment(Alignment.getQuantity());
3703 return ConstantAddress(GV, Alignment);
3707 SmallString<256> MangledNameBuffer;
3708 StringRef GlobalVariableName;
3709 llvm::GlobalValue::LinkageTypes LT;
3711 // Mangle the string literal if the ABI allows for it. However, we cannot
3712 // do this if we are compiling with ASan or -fwritable-strings because they
3713 // rely on strings having normal linkage.
3714 if (!LangOpts.WritableStrings &&
3715 !LangOpts.Sanitize.has(SanitizerKind::Address) &&
3716 getCXXABI().getMangleContext().shouldMangleStringLiteral(S)) {
3717 llvm::raw_svector_ostream Out(MangledNameBuffer);
3718 getCXXABI().getMangleContext().mangleStringLiteral(S, Out);
3720 LT = llvm::GlobalValue::LinkOnceODRLinkage;
3721 GlobalVariableName = MangledNameBuffer;
3723 LT = llvm::GlobalValue::PrivateLinkage;
3724 GlobalVariableName = Name;
3727 auto GV = GenerateStringLiteral(C, LT, *this, GlobalVariableName, Alignment);
3731 SanitizerMD->reportGlobalToASan(GV, S->getStrTokenLoc(0), "<string literal>",
3733 return ConstantAddress(GV, Alignment);
3736 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant
3737 /// array for the given ObjCEncodeExpr node.
3739 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) {
3741 getContext().getObjCEncodingForType(E->getEncodedType(), Str);
3743 return GetAddrOfConstantCString(Str);
3746 /// GetAddrOfConstantCString - Returns a pointer to a character array containing
3747 /// the literal and a terminating '\0' character.
3748 /// The result has pointer to array type.
3749 ConstantAddress CodeGenModule::GetAddrOfConstantCString(
3750 const std::string &Str, const char *GlobalName) {
3751 StringRef StrWithNull(Str.c_str(), Str.size() + 1);
3752 CharUnits Alignment =
3753 getContext().getAlignOfGlobalVarInChars(getContext().CharTy);
3756 llvm::ConstantDataArray::getString(getLLVMContext(), StrWithNull, false);
3758 // Don't share any string literals if strings aren't constant.
3759 llvm::GlobalVariable **Entry = nullptr;
3760 if (!LangOpts.WritableStrings) {
3761 Entry = &ConstantStringMap[C];
3762 if (auto GV = *Entry) {
3763 if (Alignment.getQuantity() > GV->getAlignment())
3764 GV->setAlignment(Alignment.getQuantity());
3765 return ConstantAddress(GV, Alignment);
3769 // Get the default prefix if a name wasn't specified.
3771 GlobalName = ".str";
3772 // Create a global variable for this.
3773 auto GV = GenerateStringLiteral(C, llvm::GlobalValue::PrivateLinkage, *this,
3774 GlobalName, Alignment);
3777 return ConstantAddress(GV, Alignment);
3780 ConstantAddress CodeGenModule::GetAddrOfGlobalTemporary(
3781 const MaterializeTemporaryExpr *E, const Expr *Init) {
3782 assert((E->getStorageDuration() == SD_Static ||
3783 E->getStorageDuration() == SD_Thread) && "not a global temporary");
3784 const auto *VD = cast<VarDecl>(E->getExtendingDecl());
3786 // If we're not materializing a subobject of the temporary, keep the
3787 // cv-qualifiers from the type of the MaterializeTemporaryExpr.
3788 QualType MaterializedType = Init->getType();
3789 if (Init == E->GetTemporaryExpr())
3790 MaterializedType = E->getType();
3792 CharUnits Align = getContext().getTypeAlignInChars(MaterializedType);
3794 if (llvm::Constant *Slot = MaterializedGlobalTemporaryMap[E])
3795 return ConstantAddress(Slot, Align);
3797 // FIXME: If an externally-visible declaration extends multiple temporaries,
3798 // we need to give each temporary the same name in every translation unit (and
3799 // we also need to make the temporaries externally-visible).
3800 SmallString<256> Name;
3801 llvm::raw_svector_ostream Out(Name);
3802 getCXXABI().getMangleContext().mangleReferenceTemporary(
3803 VD, E->getManglingNumber(), Out);
3805 APValue *Value = nullptr;
3806 if (E->getStorageDuration() == SD_Static) {
3807 // We might have a cached constant initializer for this temporary. Note
3808 // that this might have a different value from the value computed by
3809 // evaluating the initializer if the surrounding constant expression
3810 // modifies the temporary.
3811 Value = getContext().getMaterializedTemporaryValue(E, false);
3812 if (Value && Value->isUninit())
3816 // Try evaluating it now, it might have a constant initializer.
3817 Expr::EvalResult EvalResult;
3818 if (!Value && Init->EvaluateAsRValue(EvalResult, getContext()) &&
3819 !EvalResult.hasSideEffects())
3820 Value = &EvalResult.Val;
3823 VD ? GetGlobalVarAddressSpace(VD) : MaterializedType.getAddressSpace();
3825 Optional<ConstantEmitter> emitter;
3826 llvm::Constant *InitialValue = nullptr;
3827 bool Constant = false;
3830 // The temporary has a constant initializer, use it.
3831 emitter.emplace(*this);
3832 InitialValue = emitter->emitForInitializer(*Value, AddrSpace,
3834 Constant = isTypeConstant(MaterializedType, /*ExcludeCtor*/Value);
3835 Type = InitialValue->getType();
3837 // No initializer, the initialization will be provided when we
3838 // initialize the declaration which performed lifetime extension.
3839 Type = getTypes().ConvertTypeForMem(MaterializedType);
3842 // Create a global variable for this lifetime-extended temporary.
3843 llvm::GlobalValue::LinkageTypes Linkage =
3844 getLLVMLinkageVarDefinition(VD, Constant);
3845 if (Linkage == llvm::GlobalVariable::ExternalLinkage) {
3846 const VarDecl *InitVD;
3847 if (VD->isStaticDataMember() && VD->getAnyInitializer(InitVD) &&
3848 isa<CXXRecordDecl>(InitVD->getLexicalDeclContext())) {
3849 // Temporaries defined inside a class get linkonce_odr linkage because the
3850 // class can be defined in multipe translation units.
3851 Linkage = llvm::GlobalVariable::LinkOnceODRLinkage;
3853 // There is no need for this temporary to have external linkage if the
3854 // VarDecl has external linkage.
3855 Linkage = llvm::GlobalVariable::InternalLinkage;
3858 auto TargetAS = getContext().getTargetAddressSpace(AddrSpace);
3859 auto *GV = new llvm::GlobalVariable(
3860 getModule(), Type, Constant, Linkage, InitialValue, Name.c_str(),
3861 /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal, TargetAS);
3862 if (emitter) emitter->finalize(GV);
3863 setGlobalVisibility(GV, VD, ForDefinition);
3864 GV->setAlignment(Align.getQuantity());
3865 if (supportsCOMDAT() && GV->isWeakForLinker())
3866 GV->setComdat(TheModule.getOrInsertComdat(GV->getName()));
3867 if (VD->getTLSKind())
3868 setTLSMode(GV, *VD);
3869 llvm::Constant *CV = GV;
3870 if (AddrSpace != LangAS::Default)
3871 CV = getTargetCodeGenInfo().performAddrSpaceCast(
3872 *this, GV, AddrSpace, LangAS::Default,
3874 getContext().getTargetAddressSpace(LangAS::Default)));
3875 MaterializedGlobalTemporaryMap[E] = CV;
3876 return ConstantAddress(CV, Align);
3879 /// EmitObjCPropertyImplementations - Emit information for synthesized
3880 /// properties for an implementation.
3881 void CodeGenModule::EmitObjCPropertyImplementations(const
3882 ObjCImplementationDecl *D) {
3883 for (const auto *PID : D->property_impls()) {
3884 // Dynamic is just for type-checking.
3885 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) {
3886 ObjCPropertyDecl *PD = PID->getPropertyDecl();
3888 // Determine which methods need to be implemented, some may have
3889 // been overridden. Note that ::isPropertyAccessor is not the method
3890 // we want, that just indicates if the decl came from a
3891 // property. What we want to know is if the method is defined in
3892 // this implementation.
3893 if (!D->getInstanceMethod(PD->getGetterName()))
3894 CodeGenFunction(*this).GenerateObjCGetter(
3895 const_cast<ObjCImplementationDecl *>(D), PID);
3896 if (!PD->isReadOnly() &&
3897 !D->getInstanceMethod(PD->getSetterName()))
3898 CodeGenFunction(*this).GenerateObjCSetter(
3899 const_cast<ObjCImplementationDecl *>(D), PID);
3904 static bool needsDestructMethod(ObjCImplementationDecl *impl) {
3905 const ObjCInterfaceDecl *iface = impl->getClassInterface();
3906 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
3907 ivar; ivar = ivar->getNextIvar())
3908 if (ivar->getType().isDestructedType())
3914 static bool AllTrivialInitializers(CodeGenModule &CGM,
3915 ObjCImplementationDecl *D) {
3916 CodeGenFunction CGF(CGM);
3917 for (ObjCImplementationDecl::init_iterator B = D->init_begin(),
3918 E = D->init_end(); B != E; ++B) {
3919 CXXCtorInitializer *CtorInitExp = *B;
3920 Expr *Init = CtorInitExp->getInit();
3921 if (!CGF.isTrivialInitializer(Init))
3927 /// EmitObjCIvarInitializations - Emit information for ivar initialization
3928 /// for an implementation.
3929 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) {
3930 // We might need a .cxx_destruct even if we don't have any ivar initializers.
3931 if (needsDestructMethod(D)) {
3932 IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct");
3933 Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
3934 ObjCMethodDecl *DTORMethod =
3935 ObjCMethodDecl::Create(getContext(), D->getLocation(), D->getLocation(),
3936 cxxSelector, getContext().VoidTy, nullptr, D,
3937 /*isInstance=*/true, /*isVariadic=*/false,
3938 /*isPropertyAccessor=*/true, /*isImplicitlyDeclared=*/true,
3939 /*isDefined=*/false, ObjCMethodDecl::Required);
3940 D->addInstanceMethod(DTORMethod);
3941 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false);
3942 D->setHasDestructors(true);
3945 // If the implementation doesn't have any ivar initializers, we don't need
3946 // a .cxx_construct.
3947 if (D->getNumIvarInitializers() == 0 ||
3948 AllTrivialInitializers(*this, D))
3951 IdentifierInfo *II = &getContext().Idents.get(".cxx_construct");
3952 Selector cxxSelector = getContext().Selectors.getSelector(0, &II);
3953 // The constructor returns 'self'.
3954 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create(getContext(),
3958 getContext().getObjCIdType(),
3959 nullptr, D, /*isInstance=*/true,
3960 /*isVariadic=*/false,
3961 /*isPropertyAccessor=*/true,
3962 /*isImplicitlyDeclared=*/true,
3963 /*isDefined=*/false,
3964 ObjCMethodDecl::Required);
3965 D->addInstanceMethod(CTORMethod);
3966 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true);
3967 D->setHasNonZeroConstructors(true);
3970 // EmitLinkageSpec - Emit all declarations in a linkage spec.
3971 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) {
3972 if (LSD->getLanguage() != LinkageSpecDecl::lang_c &&
3973 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) {
3974 ErrorUnsupported(LSD, "linkage spec");
3978 EmitDeclContext(LSD);
3981 void CodeGenModule::EmitDeclContext(const DeclContext *DC) {
3982 for (auto *I : DC->decls()) {
3983 // Unlike other DeclContexts, the contents of an ObjCImplDecl at TU scope
3984 // are themselves considered "top-level", so EmitTopLevelDecl on an
3985 // ObjCImplDecl does not recursively visit them. We need to do that in
3986 // case they're nested inside another construct (LinkageSpecDecl /
3987 // ExportDecl) that does stop them from being considered "top-level".
3988 if (auto *OID = dyn_cast<ObjCImplDecl>(I)) {
3989 for (auto *M : OID->methods())
3990 EmitTopLevelDecl(M);
3993 EmitTopLevelDecl(I);
3997 /// EmitTopLevelDecl - Emit code for a single top level declaration.
3998 void CodeGenModule::EmitTopLevelDecl(Decl *D) {
3999 // Ignore dependent declarations.
4000 if (D->getDeclContext() && D->getDeclContext()->isDependentContext())
4003 switch (D->getKind()) {
4004 case Decl::CXXConversion:
4005 case Decl::CXXMethod:
4006 case Decl::Function:
4007 // Skip function templates
4008 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() ||
4009 cast<FunctionDecl>(D)->isLateTemplateParsed())
4012 EmitGlobal(cast<FunctionDecl>(D));
4013 // Always provide some coverage mapping
4014 // even for the functions that aren't emitted.
4015 AddDeferredUnusedCoverageMapping(D);
4018 case Decl::CXXDeductionGuide:
4019 // Function-like, but does not result in code emission.
4023 case Decl::Decomposition:
4024 // Skip variable templates
4025 if (cast<VarDecl>(D)->getDescribedVarTemplate())
4028 case Decl::VarTemplateSpecialization:
4029 EmitGlobal(cast<VarDecl>(D));
4030 if (auto *DD = dyn_cast<DecompositionDecl>(D))
4031 for (auto *B : DD->bindings())
4032 if (auto *HD = B->getHoldingVar())
4036 // Indirect fields from global anonymous structs and unions can be
4037 // ignored; only the actual variable requires IR gen support.
4038 case Decl::IndirectField:
4042 case Decl::Namespace:
4043 EmitDeclContext(cast<NamespaceDecl>(D));
4045 case Decl::ClassTemplateSpecialization: {
4046 const auto *Spec = cast<ClassTemplateSpecializationDecl>(D);
4048 Spec->getSpecializationKind() == TSK_ExplicitInstantiationDefinition &&
4049 Spec->hasDefinition())
4050 DebugInfo->completeTemplateDefinition(*Spec);
4052 case Decl::CXXRecord:
4054 if (auto *ES = D->getASTContext().getExternalSource())
4055 if (ES->hasExternalDefinitions(D) == ExternalASTSource::EK_Never)
4056 DebugInfo->completeUnusedClass(cast<CXXRecordDecl>(*D));
4058 // Emit any static data members, they may be definitions.
4059 for (auto *I : cast<CXXRecordDecl>(D)->decls())
4060 if (isa<VarDecl>(I) || isa<CXXRecordDecl>(I))
4061 EmitTopLevelDecl(I);
4063 // No code generation needed.
4064 case Decl::UsingShadow:
4065 case Decl::ClassTemplate:
4066 case Decl::VarTemplate:
4067 case Decl::VarTemplatePartialSpecialization:
4068 case Decl::FunctionTemplate:
4069 case Decl::TypeAliasTemplate:
4073 case Decl::Using: // using X; [C++]
4074 if (CGDebugInfo *DI = getModuleDebugInfo())
4075 DI->EmitUsingDecl(cast<UsingDecl>(*D));
4077 case Decl::NamespaceAlias:
4078 if (CGDebugInfo *DI = getModuleDebugInfo())
4079 DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(*D));
4081 case Decl::UsingDirective: // using namespace X; [C++]
4082 if (CGDebugInfo *DI = getModuleDebugInfo())
4083 DI->EmitUsingDirective(cast<UsingDirectiveDecl>(*D));
4085 case Decl::CXXConstructor:
4086 // Skip function templates
4087 if (cast<FunctionDecl>(D)->getDescribedFunctionTemplate() ||
4088 cast<FunctionDecl>(D)->isLateTemplateParsed())
4091 getCXXABI().EmitCXXConstructors(cast<CXXConstructorDecl>(D));
4093 case Decl::CXXDestructor:
4094 if (cast<FunctionDecl>(D)->isLateTemplateParsed())
4096 getCXXABI().EmitCXXDestructors(cast<CXXDestructorDecl>(D));
4099 case Decl::StaticAssert:
4103 // Objective-C Decls
4105 // Forward declarations, no (immediate) code generation.
4106 case Decl::ObjCInterface:
4107 case Decl::ObjCCategory:
4110 case Decl::ObjCProtocol: {
4111 auto *Proto = cast<ObjCProtocolDecl>(D);
4112 if (Proto->isThisDeclarationADefinition())
4113 ObjCRuntime->GenerateProtocol(Proto);
4117 case Decl::ObjCCategoryImpl:
4118 // Categories have properties but don't support synthesize so we
4119 // can ignore them here.
4120 ObjCRuntime->GenerateCategory(cast<ObjCCategoryImplDecl>(D));
4123 case Decl::ObjCImplementation: {
4124 auto *OMD = cast<ObjCImplementationDecl>(D);
4125 EmitObjCPropertyImplementations(OMD);
4126 EmitObjCIvarInitializations(OMD);
4127 ObjCRuntime->GenerateClass(OMD);
4128 // Emit global variable debug information.
4129 if (CGDebugInfo *DI = getModuleDebugInfo())
4130 if (getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo)
4131 DI->getOrCreateInterfaceType(getContext().getObjCInterfaceType(
4132 OMD->getClassInterface()), OMD->getLocation());
4135 case Decl::ObjCMethod: {
4136 auto *OMD = cast<ObjCMethodDecl>(D);
4137 // If this is not a prototype, emit the body.
4139 CodeGenFunction(*this).GenerateObjCMethod(OMD);
4142 case Decl::ObjCCompatibleAlias:
4143 ObjCRuntime->RegisterAlias(cast<ObjCCompatibleAliasDecl>(D));
4146 case Decl::PragmaComment: {
4147 const auto *PCD = cast<PragmaCommentDecl>(D);
4148 switch (PCD->getCommentKind()) {
4150 llvm_unreachable("unexpected pragma comment kind");
4152 AppendLinkerOptions(PCD->getArg());
4155 AddDependentLib(PCD->getArg());
4160 break; // We ignore all of these.
4165 case Decl::PragmaDetectMismatch: {
4166 const auto *PDMD = cast<PragmaDetectMismatchDecl>(D);
4167 AddDetectMismatch(PDMD->getName(), PDMD->getValue());
4171 case Decl::LinkageSpec:
4172 EmitLinkageSpec(cast<LinkageSpecDecl>(D));
4175 case Decl::FileScopeAsm: {
4176 // File-scope asm is ignored during device-side CUDA compilation.
4177 if (LangOpts.CUDA && LangOpts.CUDAIsDevice)
4179 // File-scope asm is ignored during device-side OpenMP compilation.
4180 if (LangOpts.OpenMPIsDevice)
4182 auto *AD = cast<FileScopeAsmDecl>(D);
4183 getModule().appendModuleInlineAsm(AD->getAsmString()->getString());
4187 case Decl::Import: {
4188 auto *Import = cast<ImportDecl>(D);
4190 // If we've already imported this module, we're done.
4191 if (!ImportedModules.insert(Import->getImportedModule()))
4194 // Emit debug information for direct imports.
4195 if (!Import->getImportedOwningModule()) {
4196 if (CGDebugInfo *DI = getModuleDebugInfo())
4197 DI->EmitImportDecl(*Import);
4200 // Find all of the submodules and emit the module initializers.
4201 llvm::SmallPtrSet<clang::Module *, 16> Visited;
4202 SmallVector<clang::Module *, 16> Stack;
4203 Visited.insert(Import->getImportedModule());
4204 Stack.push_back(Import->getImportedModule());
4206 while (!Stack.empty()) {
4207 clang::Module *Mod = Stack.pop_back_val();
4208 if (!EmittedModuleInitializers.insert(Mod).second)
4211 for (auto *D : Context.getModuleInitializers(Mod))
4212 EmitTopLevelDecl(D);
4214 // Visit the submodules of this module.
4215 for (clang::Module::submodule_iterator Sub = Mod->submodule_begin(),
4216 SubEnd = Mod->submodule_end();
4217 Sub != SubEnd; ++Sub) {
4218 // Skip explicit children; they need to be explicitly imported to emit
4219 // the initializers.
4220 if ((*Sub)->IsExplicit)
4223 if (Visited.insert(*Sub).second)
4224 Stack.push_back(*Sub);
4231 EmitDeclContext(cast<ExportDecl>(D));
4234 case Decl::OMPThreadPrivate:
4235 EmitOMPThreadPrivateDecl(cast<OMPThreadPrivateDecl>(D));
4238 case Decl::OMPDeclareReduction:
4239 EmitOMPDeclareReduction(cast<OMPDeclareReductionDecl>(D));
4243 // Make sure we handled everything we should, every other kind is a
4244 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind
4245 // function. Need to recode Decl::Kind to do that easily.
4246 assert(isa<TypeDecl>(D) && "Unsupported decl kind");
4251 void CodeGenModule::AddDeferredUnusedCoverageMapping(Decl *D) {
4252 // Do we need to generate coverage mapping?
4253 if (!CodeGenOpts.CoverageMapping)
4255 switch (D->getKind()) {
4256 case Decl::CXXConversion:
4257 case Decl::CXXMethod:
4258 case Decl::Function:
4259 case Decl::ObjCMethod:
4260 case Decl::CXXConstructor:
4261 case Decl::CXXDestructor: {
4262 if (!cast<FunctionDecl>(D)->doesThisDeclarationHaveABody())
4264 SourceManager &SM = getContext().getSourceManager();
4265 if (LimitedCoverage && SM.getMainFileID() != SM.getFileID(D->getLocStart()))
4267 auto I = DeferredEmptyCoverageMappingDecls.find(D);
4268 if (I == DeferredEmptyCoverageMappingDecls.end())
4269 DeferredEmptyCoverageMappingDecls[D] = true;
4277 void CodeGenModule::ClearUnusedCoverageMapping(const Decl *D) {
4278 // Do we need to generate coverage mapping?
4279 if (!CodeGenOpts.CoverageMapping)
4281 if (const auto *Fn = dyn_cast<FunctionDecl>(D)) {
4282 if (Fn->isTemplateInstantiation())
4283 ClearUnusedCoverageMapping(Fn->getTemplateInstantiationPattern());
4285 auto I = DeferredEmptyCoverageMappingDecls.find(D);
4286 if (I == DeferredEmptyCoverageMappingDecls.end())
4287 DeferredEmptyCoverageMappingDecls[D] = false;
4292 void CodeGenModule::EmitDeferredUnusedCoverageMappings() {
4293 // We call takeVector() here to avoid use-after-free.
4294 // FIXME: DeferredEmptyCoverageMappingDecls is getting mutated because
4295 // we deserialize function bodies to emit coverage info for them, and that
4296 // deserializes more declarations. How should we handle that case?
4297 for (const auto &Entry : DeferredEmptyCoverageMappingDecls.takeVector()) {
4300 const Decl *D = Entry.first;
4301 switch (D->getKind()) {
4302 case Decl::CXXConversion:
4303 case Decl::CXXMethod:
4304 case Decl::Function:
4305 case Decl::ObjCMethod: {
4306 CodeGenPGO PGO(*this);
4307 GlobalDecl GD(cast<FunctionDecl>(D));
4308 PGO.emitEmptyCounterMapping(D, getMangledName(GD),
4309 getFunctionLinkage(GD));
4312 case Decl::CXXConstructor: {
4313 CodeGenPGO PGO(*this);
4314 GlobalDecl GD(cast<CXXConstructorDecl>(D), Ctor_Base);
4315 PGO.emitEmptyCounterMapping(D, getMangledName(GD),
4316 getFunctionLinkage(GD));
4319 case Decl::CXXDestructor: {
4320 CodeGenPGO PGO(*this);
4321 GlobalDecl GD(cast<CXXDestructorDecl>(D), Dtor_Base);
4322 PGO.emitEmptyCounterMapping(D, getMangledName(GD),
4323 getFunctionLinkage(GD));
4332 /// Turns the given pointer into a constant.
4333 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context,
4335 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr);
4336 llvm::Type *i64 = llvm::Type::getInt64Ty(Context);
4337 return llvm::ConstantInt::get(i64, PtrInt);
4340 static void EmitGlobalDeclMetadata(CodeGenModule &CGM,
4341 llvm::NamedMDNode *&GlobalMetadata,
4343 llvm::GlobalValue *Addr) {
4344 if (!GlobalMetadata)
4346 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs");
4348 // TODO: should we report variant information for ctors/dtors?
4349 llvm::Metadata *Ops[] = {llvm::ConstantAsMetadata::get(Addr),
4350 llvm::ConstantAsMetadata::get(GetPointerConstant(
4351 CGM.getLLVMContext(), D.getDecl()))};
4352 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops));
4355 /// For each function which is declared within an extern "C" region and marked
4356 /// as 'used', but has internal linkage, create an alias from the unmangled
4357 /// name to the mangled name if possible. People expect to be able to refer
4358 /// to such functions with an unmangled name from inline assembly within the
4359 /// same translation unit.
4360 void CodeGenModule::EmitStaticExternCAliases() {
4361 // Don't do anything if we're generating CUDA device code -- the NVPTX
4362 // assembly target doesn't support aliases.
4363 if (Context.getTargetInfo().getTriple().isNVPTX())
4365 for (auto &I : StaticExternCValues) {
4366 IdentifierInfo *Name = I.first;
4367 llvm::GlobalValue *Val = I.second;
4368 if (Val && !getModule().getNamedValue(Name->getName()))
4369 addUsedGlobal(llvm::GlobalAlias::create(Name->getName(), Val));
4373 bool CodeGenModule::lookupRepresentativeDecl(StringRef MangledName,
4374 GlobalDecl &Result) const {
4375 auto Res = Manglings.find(MangledName);
4376 if (Res == Manglings.end())
4378 Result = Res->getValue();
4382 /// Emits metadata nodes associating all the global values in the
4383 /// current module with the Decls they came from. This is useful for
4384 /// projects using IR gen as a subroutine.
4386 /// Since there's currently no way to associate an MDNode directly
4387 /// with an llvm::GlobalValue, we create a global named metadata
4388 /// with the name 'clang.global.decl.ptrs'.
4389 void CodeGenModule::EmitDeclMetadata() {
4390 llvm::NamedMDNode *GlobalMetadata = nullptr;
4392 for (auto &I : MangledDeclNames) {
4393 llvm::GlobalValue *Addr = getModule().getNamedValue(I.second);
4394 // Some mangled names don't necessarily have an associated GlobalValue
4395 // in this module, e.g. if we mangled it for DebugInfo.
4397 EmitGlobalDeclMetadata(*this, GlobalMetadata, I.first, Addr);
4401 /// Emits metadata nodes for all the local variables in the current
4403 void CodeGenFunction::EmitDeclMetadata() {
4404 if (LocalDeclMap.empty()) return;
4406 llvm::LLVMContext &Context = getLLVMContext();
4408 // Find the unique metadata ID for this name.
4409 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr");
4411 llvm::NamedMDNode *GlobalMetadata = nullptr;
4413 for (auto &I : LocalDeclMap) {
4414 const Decl *D = I.first;
4415 llvm::Value *Addr = I.second.getPointer();
4416 if (auto *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) {
4417 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D);
4418 Alloca->setMetadata(
4419 DeclPtrKind, llvm::MDNode::get(
4420 Context, llvm::ValueAsMetadata::getConstant(DAddr)));
4421 } else if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr)) {
4422 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D));
4423 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV);
4428 void CodeGenModule::EmitVersionIdentMetadata() {
4429 llvm::NamedMDNode *IdentMetadata =
4430 TheModule.getOrInsertNamedMetadata("llvm.ident");
4431 std::string Version = getClangFullVersion();
4432 llvm::LLVMContext &Ctx = TheModule.getContext();
4434 llvm::Metadata *IdentNode[] = {llvm::MDString::get(Ctx, Version)};
4435 IdentMetadata->addOperand(llvm::MDNode::get(Ctx, IdentNode));
4438 void CodeGenModule::EmitTargetMetadata() {
4439 // Warning, new MangledDeclNames may be appended within this loop.
4440 // We rely on MapVector insertions adding new elements to the end
4441 // of the container.
4442 // FIXME: Move this loop into the one target that needs it, and only
4443 // loop over those declarations for which we couldn't emit the target
4444 // metadata when we emitted the declaration.
4445 for (unsigned I = 0; I != MangledDeclNames.size(); ++I) {
4446 auto Val = *(MangledDeclNames.begin() + I);
4447 const Decl *D = Val.first.getDecl()->getMostRecentDecl();
4448 llvm::GlobalValue *GV = GetGlobalValue(Val.second);
4449 getTargetCodeGenInfo().emitTargetMD(D, GV, *this);
4453 void CodeGenModule::EmitCoverageFile() {
4454 if (getCodeGenOpts().CoverageDataFile.empty() &&
4455 getCodeGenOpts().CoverageNotesFile.empty())
4458 llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu");
4462 llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov");
4463 llvm::LLVMContext &Ctx = TheModule.getContext();
4464 auto *CoverageDataFile =
4465 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageDataFile);
4466 auto *CoverageNotesFile =
4467 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageNotesFile);
4468 for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) {
4469 llvm::MDNode *CU = CUNode->getOperand(i);
4470 llvm::Metadata *Elts[] = {CoverageNotesFile, CoverageDataFile, CU};
4471 GCov->addOperand(llvm::MDNode::get(Ctx, Elts));
4475 llvm::Constant *CodeGenModule::EmitUuidofInitializer(StringRef Uuid) {
4476 // Sema has checked that all uuid strings are of the form
4477 // "12345678-1234-1234-1234-1234567890ab".
4478 assert(Uuid.size() == 36);
4479 for (unsigned i = 0; i < 36; ++i) {
4480 if (i == 8 || i == 13 || i == 18 || i == 23) assert(Uuid[i] == '-');
4481 else assert(isHexDigit(Uuid[i]));
4484 // The starts of all bytes of Field3 in Uuid. Field 3 is "1234-1234567890ab".
4485 const unsigned Field3ValueOffsets[8] = { 19, 21, 24, 26, 28, 30, 32, 34 };
4487 llvm::Constant *Field3[8];
4488 for (unsigned Idx = 0; Idx < 8; ++Idx)
4489 Field3[Idx] = llvm::ConstantInt::get(
4490 Int8Ty, Uuid.substr(Field3ValueOffsets[Idx], 2), 16);
4492 llvm::Constant *Fields[4] = {
4493 llvm::ConstantInt::get(Int32Ty, Uuid.substr(0, 8), 16),
4494 llvm::ConstantInt::get(Int16Ty, Uuid.substr(9, 4), 16),
4495 llvm::ConstantInt::get(Int16Ty, Uuid.substr(14, 4), 16),
4496 llvm::ConstantArray::get(llvm::ArrayType::get(Int8Ty, 8), Field3)
4499 return llvm::ConstantStruct::getAnon(Fields);
4502 llvm::Constant *CodeGenModule::GetAddrOfRTTIDescriptor(QualType Ty,
4504 // Return a bogus pointer if RTTI is disabled, unless it's for EH.
4505 // FIXME: should we even be calling this method if RTTI is disabled
4506 // and it's not for EH?
4507 if (!ForEH && !getLangOpts().RTTI)
4508 return llvm::Constant::getNullValue(Int8PtrTy);
4510 if (ForEH && Ty->isObjCObjectPointerType() &&
4511 LangOpts.ObjCRuntime.isGNUFamily())
4512 return ObjCRuntime->GetEHType(Ty);
4514 return getCXXABI().getAddrOfRTTIDescriptor(Ty);
4517 void CodeGenModule::EmitOMPThreadPrivateDecl(const OMPThreadPrivateDecl *D) {
4518 for (auto RefExpr : D->varlists()) {
4519 auto *VD = cast<VarDecl>(cast<DeclRefExpr>(RefExpr)->getDecl());
4521 VD->getAnyInitializer() &&
4522 !VD->getAnyInitializer()->isConstantInitializer(getContext(),
4525 Address Addr(GetAddrOfGlobalVar(VD), getContext().getDeclAlign(VD));
4526 if (auto InitFunction = getOpenMPRuntime().emitThreadPrivateVarDefinition(
4527 VD, Addr, RefExpr->getLocStart(), PerformInit))
4528 CXXGlobalInits.push_back(InitFunction);
4532 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierForType(QualType T) {
4533 llvm::Metadata *&InternalId = MetadataIdMap[T.getCanonicalType()];
4537 if (isExternallyVisible(T->getLinkage())) {
4538 std::string OutName;
4539 llvm::raw_string_ostream Out(OutName);
4540 getCXXABI().getMangleContext().mangleTypeName(T, Out);
4542 InternalId = llvm::MDString::get(getLLVMContext(), Out.str());
4544 InternalId = llvm::MDNode::getDistinct(getLLVMContext(),
4545 llvm::ArrayRef<llvm::Metadata *>());
4551 // Generalize pointer types to a void pointer with the qualifiers of the
4552 // originally pointed-to type, e.g. 'const char *' and 'char * const *'
4553 // generalize to 'const void *' while 'char *' and 'const char **' generalize to
4555 static QualType GeneralizeType(ASTContext &Ctx, QualType Ty) {
4556 if (!Ty->isPointerType())
4559 return Ctx.getPointerType(
4560 QualType(Ctx.VoidTy).withCVRQualifiers(
4561 Ty->getPointeeType().getCVRQualifiers()));
4564 // Apply type generalization to a FunctionType's return and argument types
4565 static QualType GeneralizeFunctionType(ASTContext &Ctx, QualType Ty) {
4566 if (auto *FnType = Ty->getAs<FunctionProtoType>()) {
4567 SmallVector<QualType, 8> GeneralizedParams;
4568 for (auto &Param : FnType->param_types())
4569 GeneralizedParams.push_back(GeneralizeType(Ctx, Param));
4571 return Ctx.getFunctionType(
4572 GeneralizeType(Ctx, FnType->getReturnType()),
4573 GeneralizedParams, FnType->getExtProtoInfo());
4576 if (auto *FnType = Ty->getAs<FunctionNoProtoType>())
4577 return Ctx.getFunctionNoProtoType(
4578 GeneralizeType(Ctx, FnType->getReturnType()));
4580 llvm_unreachable("Encountered unknown FunctionType");
4583 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierGeneralized(QualType T) {
4584 T = GeneralizeFunctionType(getContext(), T);
4586 llvm::Metadata *&InternalId = GeneralizedMetadataIdMap[T.getCanonicalType()];
4590 if (isExternallyVisible(T->getLinkage())) {
4591 std::string OutName;
4592 llvm::raw_string_ostream Out(OutName);
4593 getCXXABI().getMangleContext().mangleTypeName(T, Out);
4594 Out << ".generalized";
4596 InternalId = llvm::MDString::get(getLLVMContext(), Out.str());
4598 InternalId = llvm::MDNode::getDistinct(getLLVMContext(),
4599 llvm::ArrayRef<llvm::Metadata *>());
4605 /// Returns whether this module needs the "all-vtables" type identifier.
4606 bool CodeGenModule::NeedAllVtablesTypeId() const {
4607 // Returns true if at least one of vtable-based CFI checkers is enabled and
4608 // is not in the trapping mode.
4609 return ((LangOpts.Sanitize.has(SanitizerKind::CFIVCall) &&
4610 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIVCall)) ||
4611 (LangOpts.Sanitize.has(SanitizerKind::CFINVCall) &&
4612 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFINVCall)) ||
4613 (LangOpts.Sanitize.has(SanitizerKind::CFIDerivedCast) &&
4614 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIDerivedCast)) ||
4615 (LangOpts.Sanitize.has(SanitizerKind::CFIUnrelatedCast) &&
4616 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIUnrelatedCast)));
4619 void CodeGenModule::AddVTableTypeMetadata(llvm::GlobalVariable *VTable,
4621 const CXXRecordDecl *RD) {
4622 llvm::Metadata *MD =
4623 CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0));
4624 VTable->addTypeMetadata(Offset.getQuantity(), MD);
4626 if (CodeGenOpts.SanitizeCfiCrossDso)
4627 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD))
4628 VTable->addTypeMetadata(Offset.getQuantity(),
4629 llvm::ConstantAsMetadata::get(CrossDsoTypeId));
4631 if (NeedAllVtablesTypeId()) {
4632 llvm::Metadata *MD = llvm::MDString::get(getLLVMContext(), "all-vtables");
4633 VTable->addTypeMetadata(Offset.getQuantity(), MD);
4637 // Fills in the supplied string map with the set of target features for the
4638 // passed in function.
4639 void CodeGenModule::getFunctionFeatureMap(llvm::StringMap<bool> &FeatureMap,
4640 const FunctionDecl *FD) {
4641 StringRef TargetCPU = Target.getTargetOpts().CPU;
4642 if (const auto *TD = FD->getAttr<TargetAttr>()) {
4643 // If we have a TargetAttr build up the feature map based on that.
4644 TargetAttr::ParsedTargetAttr ParsedAttr = TD->parse();
4646 ParsedAttr.Features.erase(
4647 llvm::remove_if(ParsedAttr.Features,
4648 [&](const std::string &Feat) {
4649 return !Target.isValidFeatureName(
4650 StringRef{Feat}.substr(1));
4652 ParsedAttr.Features.end());
4654 // Make a copy of the features as passed on the command line into the
4655 // beginning of the additional features from the function to override.
4656 ParsedAttr.Features.insert(ParsedAttr.Features.begin(),
4657 Target.getTargetOpts().FeaturesAsWritten.begin(),
4658 Target.getTargetOpts().FeaturesAsWritten.end());
4660 if (ParsedAttr.Architecture != "" &&
4661 Target.isValidCPUName(ParsedAttr.Architecture))
4662 TargetCPU = ParsedAttr.Architecture;
4664 // Now populate the feature map, first with the TargetCPU which is either
4665 // the default or a new one from the target attribute string. Then we'll use
4666 // the passed in features (FeaturesAsWritten) along with the new ones from
4668 Target.initFeatureMap(FeatureMap, getDiags(), TargetCPU,
4669 ParsedAttr.Features);
4671 Target.initFeatureMap(FeatureMap, getDiags(), TargetCPU,
4672 Target.getTargetOpts().Features);
4676 llvm::SanitizerStatReport &CodeGenModule::getSanStats() {
4678 SanStats = llvm::make_unique<llvm::SanitizerStatReport>(&getModule());
4683 CodeGenModule::createOpenCLIntToSamplerConversion(const Expr *E,
4684 CodeGenFunction &CGF) {
4685 llvm::Constant *C = ConstantEmitter(CGF).emitAbstract(E, E->getType());
4686 auto SamplerT = getOpenCLRuntime().getSamplerType(E->getType().getTypePtr());
4687 auto FTy = llvm::FunctionType::get(SamplerT, {C->getType()}, false);
4688 return CGF.Builder.CreateCall(CreateRuntimeFunction(FTy,
4689 "__translate_sampler_initializer"),