1 //===--- CodeGenModule.cpp - Emit LLVM Code from ASTs for a Module --------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This coordinates the per-module state used while generating code. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "CodeGenModule.h" 14 #include "CGBlocks.h" 15 #include "CGCUDARuntime.h" 16 #include "CGCXXABI.h" 17 #include "CGCall.h" 18 #include "CGDebugInfo.h" 19 #include "CGObjCRuntime.h" 20 #include "CGOpenCLRuntime.h" 21 #include "CGOpenMPRuntime.h" 22 #include "CGOpenMPRuntimeNVPTX.h" 23 #include "CodeGenFunction.h" 24 #include "CodeGenPGO.h" 25 #include "ConstantEmitter.h" 26 #include "CoverageMappingGen.h" 27 #include "TargetInfo.h" 28 #include "clang/AST/ASTContext.h" 29 #include "clang/AST/CharUnits.h" 30 #include "clang/AST/DeclCXX.h" 31 #include "clang/AST/DeclObjC.h" 32 #include "clang/AST/DeclTemplate.h" 33 #include "clang/AST/Mangle.h" 34 #include "clang/AST/RecordLayout.h" 35 #include "clang/AST/RecursiveASTVisitor.h" 36 #include "clang/AST/StmtVisitor.h" 37 #include "clang/Basic/Builtins.h" 38 #include "clang/Basic/CharInfo.h" 39 #include "clang/Basic/CodeGenOptions.h" 40 #include "clang/Basic/Diagnostic.h" 41 #include "clang/Basic/Module.h" 42 #include "clang/Basic/SourceManager.h" 43 #include "clang/Basic/TargetInfo.h" 44 #include "clang/Basic/Version.h" 45 #include "clang/CodeGen/ConstantInitBuilder.h" 46 #include "clang/Frontend/FrontendDiagnostic.h" 47 #include "llvm/ADT/StringSwitch.h" 48 #include "llvm/ADT/Triple.h" 49 #include "llvm/Analysis/TargetLibraryInfo.h" 50 #include "llvm/Frontend/OpenMP/OMPIRBuilder.h" 51 #include "llvm/IR/CallingConv.h" 52 #include "llvm/IR/DataLayout.h" 53 #include "llvm/IR/Intrinsics.h" 54 #include "llvm/IR/LLVMContext.h" 55 #include "llvm/IR/Module.h" 56 #include "llvm/IR/ProfileSummary.h" 57 #include "llvm/ProfileData/InstrProfReader.h" 58 #include "llvm/Support/CodeGen.h" 59 #include "llvm/Support/CommandLine.h" 60 #include "llvm/Support/ConvertUTF.h" 61 #include "llvm/Support/ErrorHandling.h" 62 #include "llvm/Support/MD5.h" 63 #include "llvm/Support/TimeProfiler.h" 64 65 using namespace clang; 66 using namespace CodeGen; 67 68 static llvm::cl::opt<bool> LimitedCoverage( 69 "limited-coverage-experimental", llvm::cl::ZeroOrMore, llvm::cl::Hidden, 70 llvm::cl::desc("Emit limited coverage mapping information (experimental)"), 71 llvm::cl::init(false)); 72 73 static const char AnnotationSection[] = "llvm.metadata"; 74 75 static CGCXXABI *createCXXABI(CodeGenModule &CGM) { 76 switch (CGM.getTarget().getCXXABI().getKind()) { 77 case TargetCXXABI::Fuchsia: 78 case TargetCXXABI::GenericAArch64: 79 case TargetCXXABI::GenericARM: 80 case TargetCXXABI::iOS: 81 case TargetCXXABI::iOS64: 82 case TargetCXXABI::WatchOS: 83 case TargetCXXABI::GenericMIPS: 84 case TargetCXXABI::GenericItanium: 85 case TargetCXXABI::WebAssembly: 86 return CreateItaniumCXXABI(CGM); 87 case TargetCXXABI::Microsoft: 88 return CreateMicrosoftCXXABI(CGM); 89 } 90 91 llvm_unreachable("invalid C++ ABI kind"); 92 } 93 94 CodeGenModule::CodeGenModule(ASTContext &C, const HeaderSearchOptions &HSO, 95 const PreprocessorOptions &PPO, 96 const CodeGenOptions &CGO, llvm::Module &M, 97 DiagnosticsEngine &diags, 98 CoverageSourceInfo *CoverageInfo) 99 : Context(C), LangOpts(C.getLangOpts()), HeaderSearchOpts(HSO), 100 PreprocessorOpts(PPO), CodeGenOpts(CGO), TheModule(M), Diags(diags), 101 Target(C.getTargetInfo()), ABI(createCXXABI(*this)), 102 VMContext(M.getContext()), Types(*this), VTables(*this), 103 SanitizerMD(new SanitizerMetadata(*this)) { 104 105 // Initialize the type cache. 106 llvm::LLVMContext &LLVMContext = M.getContext(); 107 VoidTy = llvm::Type::getVoidTy(LLVMContext); 108 Int8Ty = llvm::Type::getInt8Ty(LLVMContext); 109 Int16Ty = llvm::Type::getInt16Ty(LLVMContext); 110 Int32Ty = llvm::Type::getInt32Ty(LLVMContext); 111 Int64Ty = llvm::Type::getInt64Ty(LLVMContext); 112 HalfTy = llvm::Type::getHalfTy(LLVMContext); 113 FloatTy = llvm::Type::getFloatTy(LLVMContext); 114 DoubleTy = llvm::Type::getDoubleTy(LLVMContext); 115 PointerWidthInBits = C.getTargetInfo().getPointerWidth(0); 116 PointerAlignInBytes = 117 C.toCharUnitsFromBits(C.getTargetInfo().getPointerAlign(0)).getQuantity(); 118 SizeSizeInBytes = 119 C.toCharUnitsFromBits(C.getTargetInfo().getMaxPointerWidth()).getQuantity(); 120 IntAlignInBytes = 121 C.toCharUnitsFromBits(C.getTargetInfo().getIntAlign()).getQuantity(); 122 IntTy = llvm::IntegerType::get(LLVMContext, C.getTargetInfo().getIntWidth()); 123 IntPtrTy = llvm::IntegerType::get(LLVMContext, 124 C.getTargetInfo().getMaxPointerWidth()); 125 Int8PtrTy = Int8Ty->getPointerTo(0); 126 Int8PtrPtrTy = Int8PtrTy->getPointerTo(0); 127 AllocaInt8PtrTy = Int8Ty->getPointerTo( 128 M.getDataLayout().getAllocaAddrSpace()); 129 ASTAllocaAddressSpace = getTargetCodeGenInfo().getASTAllocaAddressSpace(); 130 131 RuntimeCC = getTargetCodeGenInfo().getABIInfo().getRuntimeCC(); 132 133 if (LangOpts.ObjC) 134 createObjCRuntime(); 135 if (LangOpts.OpenCL) 136 createOpenCLRuntime(); 137 if (LangOpts.OpenMP) 138 createOpenMPRuntime(); 139 if (LangOpts.CUDA) 140 createCUDARuntime(); 141 142 // Enable TBAA unless it's suppressed. ThreadSanitizer needs TBAA even at O0. 143 if (LangOpts.Sanitize.has(SanitizerKind::Thread) || 144 (!CodeGenOpts.RelaxedAliasing && CodeGenOpts.OptimizationLevel > 0)) 145 TBAA.reset(new CodeGenTBAA(Context, TheModule, CodeGenOpts, getLangOpts(), 146 getCXXABI().getMangleContext())); 147 148 // If debug info or coverage generation is enabled, create the CGDebugInfo 149 // object. 150 if (CodeGenOpts.getDebugInfo() != codegenoptions::NoDebugInfo || 151 CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes) 152 DebugInfo.reset(new CGDebugInfo(*this)); 153 154 Block.GlobalUniqueCount = 0; 155 156 if (C.getLangOpts().ObjC) 157 ObjCData.reset(new ObjCEntrypoints()); 158 159 if (CodeGenOpts.hasProfileClangUse()) { 160 auto ReaderOrErr = llvm::IndexedInstrProfReader::create( 161 CodeGenOpts.ProfileInstrumentUsePath, CodeGenOpts.ProfileRemappingFile); 162 if (auto E = ReaderOrErr.takeError()) { 163 unsigned DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error, 164 "Could not read profile %0: %1"); 165 llvm::handleAllErrors(std::move(E), [&](const llvm::ErrorInfoBase &EI) { 166 getDiags().Report(DiagID) << CodeGenOpts.ProfileInstrumentUsePath 167 << EI.message(); 168 }); 169 } else 170 PGOReader = std::move(ReaderOrErr.get()); 171 } 172 173 // If coverage mapping generation is enabled, create the 174 // CoverageMappingModuleGen object. 175 if (CodeGenOpts.CoverageMapping) 176 CoverageMapping.reset(new CoverageMappingModuleGen(*this, *CoverageInfo)); 177 } 178 179 CodeGenModule::~CodeGenModule() {} 180 181 void CodeGenModule::createObjCRuntime() { 182 // This is just isGNUFamily(), but we want to force implementors of 183 // new ABIs to decide how best to do this. 184 switch (LangOpts.ObjCRuntime.getKind()) { 185 case ObjCRuntime::GNUstep: 186 case ObjCRuntime::GCC: 187 case ObjCRuntime::ObjFW: 188 ObjCRuntime.reset(CreateGNUObjCRuntime(*this)); 189 return; 190 191 case ObjCRuntime::FragileMacOSX: 192 case ObjCRuntime::MacOSX: 193 case ObjCRuntime::iOS: 194 case ObjCRuntime::WatchOS: 195 ObjCRuntime.reset(CreateMacObjCRuntime(*this)); 196 return; 197 } 198 llvm_unreachable("bad runtime kind"); 199 } 200 201 void CodeGenModule::createOpenCLRuntime() { 202 OpenCLRuntime.reset(new CGOpenCLRuntime(*this)); 203 } 204 205 void CodeGenModule::createOpenMPRuntime() { 206 // Select a specialized code generation class based on the target, if any. 207 // If it does not exist use the default implementation. 208 switch (getTriple().getArch()) { 209 case llvm::Triple::nvptx: 210 case llvm::Triple::nvptx64: 211 assert(getLangOpts().OpenMPIsDevice && 212 "OpenMP NVPTX is only prepared to deal with device code."); 213 OpenMPRuntime.reset(new CGOpenMPRuntimeNVPTX(*this)); 214 break; 215 default: 216 if (LangOpts.OpenMPSimd) 217 OpenMPRuntime.reset(new CGOpenMPSIMDRuntime(*this)); 218 else 219 OpenMPRuntime.reset(new CGOpenMPRuntime(*this)); 220 break; 221 } 222 223 // The OpenMP-IR-Builder should eventually replace the above runtime codegens 224 // but we are not there yet so they both reside in CGModule for now and the 225 // OpenMP-IR-Builder is opt-in only. 226 if (LangOpts.OpenMPIRBuilder) { 227 OMPBuilder.reset(new llvm::OpenMPIRBuilder(TheModule)); 228 OMPBuilder->initialize(); 229 } 230 } 231 232 void CodeGenModule::createCUDARuntime() { 233 CUDARuntime.reset(CreateNVCUDARuntime(*this)); 234 } 235 236 void CodeGenModule::addReplacement(StringRef Name, llvm::Constant *C) { 237 Replacements[Name] = C; 238 } 239 240 void CodeGenModule::applyReplacements() { 241 for (auto &I : Replacements) { 242 StringRef MangledName = I.first(); 243 llvm::Constant *Replacement = I.second; 244 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 245 if (!Entry) 246 continue; 247 auto *OldF = cast<llvm::Function>(Entry); 248 auto *NewF = dyn_cast<llvm::Function>(Replacement); 249 if (!NewF) { 250 if (auto *Alias = dyn_cast<llvm::GlobalAlias>(Replacement)) { 251 NewF = dyn_cast<llvm::Function>(Alias->getAliasee()); 252 } else { 253 auto *CE = cast<llvm::ConstantExpr>(Replacement); 254 assert(CE->getOpcode() == llvm::Instruction::BitCast || 255 CE->getOpcode() == llvm::Instruction::GetElementPtr); 256 NewF = dyn_cast<llvm::Function>(CE->getOperand(0)); 257 } 258 } 259 260 // Replace old with new, but keep the old order. 261 OldF->replaceAllUsesWith(Replacement); 262 if (NewF) { 263 NewF->removeFromParent(); 264 OldF->getParent()->getFunctionList().insertAfter(OldF->getIterator(), 265 NewF); 266 } 267 OldF->eraseFromParent(); 268 } 269 } 270 271 void CodeGenModule::addGlobalValReplacement(llvm::GlobalValue *GV, llvm::Constant *C) { 272 GlobalValReplacements.push_back(std::make_pair(GV, C)); 273 } 274 275 void CodeGenModule::applyGlobalValReplacements() { 276 for (auto &I : GlobalValReplacements) { 277 llvm::GlobalValue *GV = I.first; 278 llvm::Constant *C = I.second; 279 280 GV->replaceAllUsesWith(C); 281 GV->eraseFromParent(); 282 } 283 } 284 285 // This is only used in aliases that we created and we know they have a 286 // linear structure. 287 static const llvm::GlobalObject *getAliasedGlobal( 288 const llvm::GlobalIndirectSymbol &GIS) { 289 llvm::SmallPtrSet<const llvm::GlobalIndirectSymbol*, 4> Visited; 290 const llvm::Constant *C = &GIS; 291 for (;;) { 292 C = C->stripPointerCasts(); 293 if (auto *GO = dyn_cast<llvm::GlobalObject>(C)) 294 return GO; 295 // stripPointerCasts will not walk over weak aliases. 296 auto *GIS2 = dyn_cast<llvm::GlobalIndirectSymbol>(C); 297 if (!GIS2) 298 return nullptr; 299 if (!Visited.insert(GIS2).second) 300 return nullptr; 301 C = GIS2->getIndirectSymbol(); 302 } 303 } 304 305 void CodeGenModule::checkAliases() { 306 // Check if the constructed aliases are well formed. It is really unfortunate 307 // that we have to do this in CodeGen, but we only construct mangled names 308 // and aliases during codegen. 309 bool Error = false; 310 DiagnosticsEngine &Diags = getDiags(); 311 for (const GlobalDecl &GD : Aliases) { 312 const auto *D = cast<ValueDecl>(GD.getDecl()); 313 SourceLocation Location; 314 bool IsIFunc = D->hasAttr<IFuncAttr>(); 315 if (const Attr *A = D->getDefiningAttr()) 316 Location = A->getLocation(); 317 else 318 llvm_unreachable("Not an alias or ifunc?"); 319 StringRef MangledName = getMangledName(GD); 320 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 321 auto *Alias = cast<llvm::GlobalIndirectSymbol>(Entry); 322 const llvm::GlobalValue *GV = getAliasedGlobal(*Alias); 323 if (!GV) { 324 Error = true; 325 Diags.Report(Location, diag::err_cyclic_alias) << IsIFunc; 326 } else if (GV->isDeclaration()) { 327 Error = true; 328 Diags.Report(Location, diag::err_alias_to_undefined) 329 << IsIFunc << IsIFunc; 330 } else if (IsIFunc) { 331 // Check resolver function type. 332 llvm::FunctionType *FTy = dyn_cast<llvm::FunctionType>( 333 GV->getType()->getPointerElementType()); 334 assert(FTy); 335 if (!FTy->getReturnType()->isPointerTy()) 336 Diags.Report(Location, diag::err_ifunc_resolver_return); 337 } 338 339 llvm::Constant *Aliasee = Alias->getIndirectSymbol(); 340 llvm::GlobalValue *AliaseeGV; 341 if (auto CE = dyn_cast<llvm::ConstantExpr>(Aliasee)) 342 AliaseeGV = cast<llvm::GlobalValue>(CE->getOperand(0)); 343 else 344 AliaseeGV = cast<llvm::GlobalValue>(Aliasee); 345 346 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) { 347 StringRef AliasSection = SA->getName(); 348 if (AliasSection != AliaseeGV->getSection()) 349 Diags.Report(SA->getLocation(), diag::warn_alias_with_section) 350 << AliasSection << IsIFunc << IsIFunc; 351 } 352 353 // We have to handle alias to weak aliases in here. LLVM itself disallows 354 // this since the object semantics would not match the IL one. For 355 // compatibility with gcc we implement it by just pointing the alias 356 // to its aliasee's aliasee. We also warn, since the user is probably 357 // expecting the link to be weak. 358 if (auto GA = dyn_cast<llvm::GlobalIndirectSymbol>(AliaseeGV)) { 359 if (GA->isInterposable()) { 360 Diags.Report(Location, diag::warn_alias_to_weak_alias) 361 << GV->getName() << GA->getName() << IsIFunc; 362 Aliasee = llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast( 363 GA->getIndirectSymbol(), Alias->getType()); 364 Alias->setIndirectSymbol(Aliasee); 365 } 366 } 367 } 368 if (!Error) 369 return; 370 371 for (const GlobalDecl &GD : Aliases) { 372 StringRef MangledName = getMangledName(GD); 373 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 374 auto *Alias = dyn_cast<llvm::GlobalIndirectSymbol>(Entry); 375 Alias->replaceAllUsesWith(llvm::UndefValue::get(Alias->getType())); 376 Alias->eraseFromParent(); 377 } 378 } 379 380 void CodeGenModule::clear() { 381 DeferredDeclsToEmit.clear(); 382 if (OpenMPRuntime) 383 OpenMPRuntime->clear(); 384 } 385 386 void InstrProfStats::reportDiagnostics(DiagnosticsEngine &Diags, 387 StringRef MainFile) { 388 if (!hasDiagnostics()) 389 return; 390 if (VisitedInMainFile > 0 && VisitedInMainFile == MissingInMainFile) { 391 if (MainFile.empty()) 392 MainFile = "<stdin>"; 393 Diags.Report(diag::warn_profile_data_unprofiled) << MainFile; 394 } else { 395 if (Mismatched > 0) 396 Diags.Report(diag::warn_profile_data_out_of_date) << Visited << Mismatched; 397 398 if (Missing > 0) 399 Diags.Report(diag::warn_profile_data_missing) << Visited << Missing; 400 } 401 } 402 403 void CodeGenModule::Release() { 404 EmitDeferred(); 405 EmitVTablesOpportunistically(); 406 applyGlobalValReplacements(); 407 applyReplacements(); 408 checkAliases(); 409 emitMultiVersionFunctions(); 410 EmitCXXGlobalInitFunc(); 411 EmitCXXGlobalDtorFunc(); 412 registerGlobalDtorsWithAtExit(); 413 EmitCXXThreadLocalInitFunc(); 414 if (ObjCRuntime) 415 if (llvm::Function *ObjCInitFunction = ObjCRuntime->ModuleInitFunction()) 416 AddGlobalCtor(ObjCInitFunction); 417 if (Context.getLangOpts().CUDA && !Context.getLangOpts().CUDAIsDevice && 418 CUDARuntime) { 419 if (llvm::Function *CudaCtorFunction = 420 CUDARuntime->makeModuleCtorFunction()) 421 AddGlobalCtor(CudaCtorFunction); 422 } 423 if (OpenMPRuntime) { 424 if (llvm::Function *OpenMPRequiresDirectiveRegFun = 425 OpenMPRuntime->emitRequiresDirectiveRegFun()) { 426 AddGlobalCtor(OpenMPRequiresDirectiveRegFun, 0); 427 } 428 OpenMPRuntime->createOffloadEntriesAndInfoMetadata(); 429 OpenMPRuntime->clear(); 430 } 431 if (PGOReader) { 432 getModule().setProfileSummary( 433 PGOReader->getSummary(/* UseCS */ false).getMD(VMContext), 434 llvm::ProfileSummary::PSK_Instr); 435 if (PGOStats.hasDiagnostics()) 436 PGOStats.reportDiagnostics(getDiags(), getCodeGenOpts().MainFileName); 437 } 438 EmitCtorList(GlobalCtors, "llvm.global_ctors"); 439 EmitCtorList(GlobalDtors, "llvm.global_dtors"); 440 EmitGlobalAnnotations(); 441 EmitStaticExternCAliases(); 442 EmitDeferredUnusedCoverageMappings(); 443 if (CoverageMapping) 444 CoverageMapping->emit(); 445 if (CodeGenOpts.SanitizeCfiCrossDso) { 446 CodeGenFunction(*this).EmitCfiCheckFail(); 447 CodeGenFunction(*this).EmitCfiCheckStub(); 448 } 449 emitAtAvailableLinkGuard(); 450 emitLLVMUsed(); 451 if (SanStats) 452 SanStats->finish(); 453 454 if (CodeGenOpts.Autolink && 455 (Context.getLangOpts().Modules || !LinkerOptionsMetadata.empty())) { 456 EmitModuleLinkOptions(); 457 } 458 459 // On ELF we pass the dependent library specifiers directly to the linker 460 // without manipulating them. This is in contrast to other platforms where 461 // they are mapped to a specific linker option by the compiler. This 462 // difference is a result of the greater variety of ELF linkers and the fact 463 // that ELF linkers tend to handle libraries in a more complicated fashion 464 // than on other platforms. This forces us to defer handling the dependent 465 // libs to the linker. 466 // 467 // CUDA/HIP device and host libraries are different. Currently there is no 468 // way to differentiate dependent libraries for host or device. Existing 469 // usage of #pragma comment(lib, *) is intended for host libraries on 470 // Windows. Therefore emit llvm.dependent-libraries only for host. 471 if (!ELFDependentLibraries.empty() && !Context.getLangOpts().CUDAIsDevice) { 472 auto *NMD = getModule().getOrInsertNamedMetadata("llvm.dependent-libraries"); 473 for (auto *MD : ELFDependentLibraries) 474 NMD->addOperand(MD); 475 } 476 477 // Record mregparm value now so it is visible through rest of codegen. 478 if (Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86) 479 getModule().addModuleFlag(llvm::Module::Error, "NumRegisterParameters", 480 CodeGenOpts.NumRegisterParameters); 481 482 if (CodeGenOpts.DwarfVersion) { 483 getModule().addModuleFlag(llvm::Module::Max, "Dwarf Version", 484 CodeGenOpts.DwarfVersion); 485 } 486 if (CodeGenOpts.EmitCodeView) { 487 // Indicate that we want CodeView in the metadata. 488 getModule().addModuleFlag(llvm::Module::Warning, "CodeView", 1); 489 } 490 if (CodeGenOpts.CodeViewGHash) { 491 getModule().addModuleFlag(llvm::Module::Warning, "CodeViewGHash", 1); 492 } 493 if (CodeGenOpts.ControlFlowGuard) { 494 // Function ID tables and checks for Control Flow Guard (cfguard=2). 495 getModule().addModuleFlag(llvm::Module::Warning, "cfguard", 2); 496 } else if (CodeGenOpts.ControlFlowGuardNoChecks) { 497 // Function ID tables for Control Flow Guard (cfguard=1). 498 getModule().addModuleFlag(llvm::Module::Warning, "cfguard", 1); 499 } 500 if (CodeGenOpts.OptimizationLevel > 0 && CodeGenOpts.StrictVTablePointers) { 501 // We don't support LTO with 2 with different StrictVTablePointers 502 // FIXME: we could support it by stripping all the information introduced 503 // by StrictVTablePointers. 504 505 getModule().addModuleFlag(llvm::Module::Error, "StrictVTablePointers",1); 506 507 llvm::Metadata *Ops[2] = { 508 llvm::MDString::get(VMContext, "StrictVTablePointers"), 509 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 510 llvm::Type::getInt32Ty(VMContext), 1))}; 511 512 getModule().addModuleFlag(llvm::Module::Require, 513 "StrictVTablePointersRequirement", 514 llvm::MDNode::get(VMContext, Ops)); 515 } 516 if (DebugInfo) 517 // We support a single version in the linked module. The LLVM 518 // parser will drop debug info with a different version number 519 // (and warn about it, too). 520 getModule().addModuleFlag(llvm::Module::Warning, "Debug Info Version", 521 llvm::DEBUG_METADATA_VERSION); 522 523 // We need to record the widths of enums and wchar_t, so that we can generate 524 // the correct build attributes in the ARM backend. wchar_size is also used by 525 // TargetLibraryInfo. 526 uint64_t WCharWidth = 527 Context.getTypeSizeInChars(Context.getWideCharType()).getQuantity(); 528 getModule().addModuleFlag(llvm::Module::Error, "wchar_size", WCharWidth); 529 530 llvm::Triple::ArchType Arch = Context.getTargetInfo().getTriple().getArch(); 531 if ( Arch == llvm::Triple::arm 532 || Arch == llvm::Triple::armeb 533 || Arch == llvm::Triple::thumb 534 || Arch == llvm::Triple::thumbeb) { 535 // The minimum width of an enum in bytes 536 uint64_t EnumWidth = Context.getLangOpts().ShortEnums ? 1 : 4; 537 getModule().addModuleFlag(llvm::Module::Error, "min_enum_size", EnumWidth); 538 } 539 540 if (Arch == llvm::Triple::riscv32 || Arch == llvm::Triple::riscv64) { 541 StringRef ABIStr = Target.getABI(); 542 llvm::LLVMContext &Ctx = TheModule.getContext(); 543 getModule().addModuleFlag(llvm::Module::Error, "target-abi", 544 llvm::MDString::get(Ctx, ABIStr)); 545 } 546 547 if (CodeGenOpts.SanitizeCfiCrossDso) { 548 // Indicate that we want cross-DSO control flow integrity checks. 549 getModule().addModuleFlag(llvm::Module::Override, "Cross-DSO CFI", 1); 550 } 551 552 if (LangOpts.Sanitize.has(SanitizerKind::CFIICall)) { 553 getModule().addModuleFlag(llvm::Module::Override, 554 "CFI Canonical Jump Tables", 555 CodeGenOpts.SanitizeCfiCanonicalJumpTables); 556 } 557 558 if (CodeGenOpts.CFProtectionReturn && 559 Target.checkCFProtectionReturnSupported(getDiags())) { 560 // Indicate that we want to instrument return control flow protection. 561 getModule().addModuleFlag(llvm::Module::Override, "cf-protection-return", 562 1); 563 } 564 565 if (CodeGenOpts.CFProtectionBranch && 566 Target.checkCFProtectionBranchSupported(getDiags())) { 567 // Indicate that we want to instrument branch control flow protection. 568 getModule().addModuleFlag(llvm::Module::Override, "cf-protection-branch", 569 1); 570 } 571 572 if (LangOpts.CUDAIsDevice && getTriple().isNVPTX()) { 573 // Indicate whether __nvvm_reflect should be configured to flush denormal 574 // floating point values to 0. (This corresponds to its "__CUDA_FTZ" 575 // property.) 576 getModule().addModuleFlag(llvm::Module::Override, "nvvm-reflect-ftz", 577 CodeGenOpts.FlushDenorm ? 1 : 0); 578 } 579 580 // Emit OpenCL specific module metadata: OpenCL/SPIR version. 581 if (LangOpts.OpenCL) { 582 EmitOpenCLMetadata(); 583 // Emit SPIR version. 584 if (getTriple().isSPIR()) { 585 // SPIR v2.0 s2.12 - The SPIR version used by the module is stored in the 586 // opencl.spir.version named metadata. 587 // C++ is backwards compatible with OpenCL v2.0. 588 auto Version = LangOpts.OpenCLCPlusPlus ? 200 : LangOpts.OpenCLVersion; 589 llvm::Metadata *SPIRVerElts[] = { 590 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 591 Int32Ty, Version / 100)), 592 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 593 Int32Ty, (Version / 100 > 1) ? 0 : 2))}; 594 llvm::NamedMDNode *SPIRVerMD = 595 TheModule.getOrInsertNamedMetadata("opencl.spir.version"); 596 llvm::LLVMContext &Ctx = TheModule.getContext(); 597 SPIRVerMD->addOperand(llvm::MDNode::get(Ctx, SPIRVerElts)); 598 } 599 } 600 601 if (uint32_t PLevel = Context.getLangOpts().PICLevel) { 602 assert(PLevel < 3 && "Invalid PIC Level"); 603 getModule().setPICLevel(static_cast<llvm::PICLevel::Level>(PLevel)); 604 if (Context.getLangOpts().PIE) 605 getModule().setPIELevel(static_cast<llvm::PIELevel::Level>(PLevel)); 606 } 607 608 if (getCodeGenOpts().CodeModel.size() > 0) { 609 unsigned CM = llvm::StringSwitch<unsigned>(getCodeGenOpts().CodeModel) 610 .Case("tiny", llvm::CodeModel::Tiny) 611 .Case("small", llvm::CodeModel::Small) 612 .Case("kernel", llvm::CodeModel::Kernel) 613 .Case("medium", llvm::CodeModel::Medium) 614 .Case("large", llvm::CodeModel::Large) 615 .Default(~0u); 616 if (CM != ~0u) { 617 llvm::CodeModel::Model codeModel = static_cast<llvm::CodeModel::Model>(CM); 618 getModule().setCodeModel(codeModel); 619 } 620 } 621 622 if (CodeGenOpts.NoPLT) 623 getModule().setRtLibUseGOT(); 624 625 SimplifyPersonality(); 626 627 if (getCodeGenOpts().EmitDeclMetadata) 628 EmitDeclMetadata(); 629 630 if (getCodeGenOpts().EmitGcovArcs || getCodeGenOpts().EmitGcovNotes) 631 EmitCoverageFile(); 632 633 if (DebugInfo) 634 DebugInfo->finalize(); 635 636 if (getCodeGenOpts().EmitVersionIdentMetadata) 637 EmitVersionIdentMetadata(); 638 639 if (!getCodeGenOpts().RecordCommandLine.empty()) 640 EmitCommandLineMetadata(); 641 642 EmitTargetMetadata(); 643 } 644 645 void CodeGenModule::EmitOpenCLMetadata() { 646 // SPIR v2.0 s2.13 - The OpenCL version used by the module is stored in the 647 // opencl.ocl.version named metadata node. 648 // C++ is backwards compatible with OpenCL v2.0. 649 // FIXME: We might need to add CXX version at some point too? 650 auto Version = LangOpts.OpenCLCPlusPlus ? 200 : LangOpts.OpenCLVersion; 651 llvm::Metadata *OCLVerElts[] = { 652 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 653 Int32Ty, Version / 100)), 654 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 655 Int32Ty, (Version % 100) / 10))}; 656 llvm::NamedMDNode *OCLVerMD = 657 TheModule.getOrInsertNamedMetadata("opencl.ocl.version"); 658 llvm::LLVMContext &Ctx = TheModule.getContext(); 659 OCLVerMD->addOperand(llvm::MDNode::get(Ctx, OCLVerElts)); 660 } 661 662 void CodeGenModule::UpdateCompletedType(const TagDecl *TD) { 663 // Make sure that this type is translated. 664 Types.UpdateCompletedType(TD); 665 } 666 667 void CodeGenModule::RefreshTypeCacheForClass(const CXXRecordDecl *RD) { 668 // Make sure that this type is translated. 669 Types.RefreshTypeCacheForClass(RD); 670 } 671 672 llvm::MDNode *CodeGenModule::getTBAATypeInfo(QualType QTy) { 673 if (!TBAA) 674 return nullptr; 675 return TBAA->getTypeInfo(QTy); 676 } 677 678 TBAAAccessInfo CodeGenModule::getTBAAAccessInfo(QualType AccessType) { 679 if (!TBAA) 680 return TBAAAccessInfo(); 681 return TBAA->getAccessInfo(AccessType); 682 } 683 684 TBAAAccessInfo 685 CodeGenModule::getTBAAVTablePtrAccessInfo(llvm::Type *VTablePtrType) { 686 if (!TBAA) 687 return TBAAAccessInfo(); 688 return TBAA->getVTablePtrAccessInfo(VTablePtrType); 689 } 690 691 llvm::MDNode *CodeGenModule::getTBAAStructInfo(QualType QTy) { 692 if (!TBAA) 693 return nullptr; 694 return TBAA->getTBAAStructInfo(QTy); 695 } 696 697 llvm::MDNode *CodeGenModule::getTBAABaseTypeInfo(QualType QTy) { 698 if (!TBAA) 699 return nullptr; 700 return TBAA->getBaseTypeInfo(QTy); 701 } 702 703 llvm::MDNode *CodeGenModule::getTBAAAccessTagInfo(TBAAAccessInfo Info) { 704 if (!TBAA) 705 return nullptr; 706 return TBAA->getAccessTagInfo(Info); 707 } 708 709 TBAAAccessInfo CodeGenModule::mergeTBAAInfoForCast(TBAAAccessInfo SourceInfo, 710 TBAAAccessInfo TargetInfo) { 711 if (!TBAA) 712 return TBAAAccessInfo(); 713 return TBAA->mergeTBAAInfoForCast(SourceInfo, TargetInfo); 714 } 715 716 TBAAAccessInfo 717 CodeGenModule::mergeTBAAInfoForConditionalOperator(TBAAAccessInfo InfoA, 718 TBAAAccessInfo InfoB) { 719 if (!TBAA) 720 return TBAAAccessInfo(); 721 return TBAA->mergeTBAAInfoForConditionalOperator(InfoA, InfoB); 722 } 723 724 TBAAAccessInfo 725 CodeGenModule::mergeTBAAInfoForMemoryTransfer(TBAAAccessInfo DestInfo, 726 TBAAAccessInfo SrcInfo) { 727 if (!TBAA) 728 return TBAAAccessInfo(); 729 return TBAA->mergeTBAAInfoForConditionalOperator(DestInfo, SrcInfo); 730 } 731 732 void CodeGenModule::DecorateInstructionWithTBAA(llvm::Instruction *Inst, 733 TBAAAccessInfo TBAAInfo) { 734 if (llvm::MDNode *Tag = getTBAAAccessTagInfo(TBAAInfo)) 735 Inst->setMetadata(llvm::LLVMContext::MD_tbaa, Tag); 736 } 737 738 void CodeGenModule::DecorateInstructionWithInvariantGroup( 739 llvm::Instruction *I, const CXXRecordDecl *RD) { 740 I->setMetadata(llvm::LLVMContext::MD_invariant_group, 741 llvm::MDNode::get(getLLVMContext(), {})); 742 } 743 744 void CodeGenModule::Error(SourceLocation loc, StringRef message) { 745 unsigned diagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, "%0"); 746 getDiags().Report(Context.getFullLoc(loc), diagID) << message; 747 } 748 749 /// ErrorUnsupported - Print out an error that codegen doesn't support the 750 /// specified stmt yet. 751 void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type) { 752 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, 753 "cannot compile this %0 yet"); 754 std::string Msg = Type; 755 getDiags().Report(Context.getFullLoc(S->getBeginLoc()), DiagID) 756 << Msg << S->getSourceRange(); 757 } 758 759 /// ErrorUnsupported - Print out an error that codegen doesn't support the 760 /// specified decl yet. 761 void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type) { 762 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, 763 "cannot compile this %0 yet"); 764 std::string Msg = Type; 765 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg; 766 } 767 768 llvm::ConstantInt *CodeGenModule::getSize(CharUnits size) { 769 return llvm::ConstantInt::get(SizeTy, size.getQuantity()); 770 } 771 772 void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV, 773 const NamedDecl *D) const { 774 if (GV->hasDLLImportStorageClass()) 775 return; 776 // Internal definitions always have default visibility. 777 if (GV->hasLocalLinkage()) { 778 GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 779 return; 780 } 781 if (!D) 782 return; 783 // Set visibility for definitions, and for declarations if requested globally 784 // or set explicitly. 785 LinkageInfo LV = D->getLinkageAndVisibility(); 786 if (LV.isVisibilityExplicit() || getLangOpts().SetVisibilityForExternDecls || 787 !GV->isDeclarationForLinker()) 788 GV->setVisibility(GetLLVMVisibility(LV.getVisibility())); 789 } 790 791 static bool shouldAssumeDSOLocal(const CodeGenModule &CGM, 792 llvm::GlobalValue *GV) { 793 if (GV->hasLocalLinkage()) 794 return true; 795 796 if (!GV->hasDefaultVisibility() && !GV->hasExternalWeakLinkage()) 797 return true; 798 799 // DLLImport explicitly marks the GV as external. 800 if (GV->hasDLLImportStorageClass()) 801 return false; 802 803 const llvm::Triple &TT = CGM.getTriple(); 804 if (TT.isWindowsGNUEnvironment()) { 805 // In MinGW, variables without DLLImport can still be automatically 806 // imported from a DLL by the linker; don't mark variables that 807 // potentially could come from another DLL as DSO local. 808 if (GV->isDeclarationForLinker() && isa<llvm::GlobalVariable>(GV) && 809 !GV->isThreadLocal()) 810 return false; 811 } 812 813 // On COFF, don't mark 'extern_weak' symbols as DSO local. If these symbols 814 // remain unresolved in the link, they can be resolved to zero, which is 815 // outside the current DSO. 816 if (TT.isOSBinFormatCOFF() && GV->hasExternalWeakLinkage()) 817 return false; 818 819 // Every other GV is local on COFF. 820 // Make an exception for windows OS in the triple: Some firmware builds use 821 // *-win32-macho triples. This (accidentally?) produced windows relocations 822 // without GOT tables in older clang versions; Keep this behaviour. 823 // FIXME: even thread local variables? 824 if (TT.isOSBinFormatCOFF() || (TT.isOSWindows() && TT.isOSBinFormatMachO())) 825 return true; 826 827 // Only handle COFF and ELF for now. 828 if (!TT.isOSBinFormatELF()) 829 return false; 830 831 // If this is not an executable, don't assume anything is local. 832 const auto &CGOpts = CGM.getCodeGenOpts(); 833 llvm::Reloc::Model RM = CGOpts.RelocationModel; 834 const auto &LOpts = CGM.getLangOpts(); 835 if (RM != llvm::Reloc::Static && !LOpts.PIE) 836 return false; 837 838 // A definition cannot be preempted from an executable. 839 if (!GV->isDeclarationForLinker()) 840 return true; 841 842 // Most PIC code sequences that assume that a symbol is local cannot produce a 843 // 0 if it turns out the symbol is undefined. While this is ABI and relocation 844 // depended, it seems worth it to handle it here. 845 if (RM == llvm::Reloc::PIC_ && GV->hasExternalWeakLinkage()) 846 return false; 847 848 // PPC has no copy relocations and cannot use a plt entry as a symbol address. 849 llvm::Triple::ArchType Arch = TT.getArch(); 850 if (Arch == llvm::Triple::ppc || Arch == llvm::Triple::ppc64 || 851 Arch == llvm::Triple::ppc64le) 852 return false; 853 854 // If we can use copy relocations we can assume it is local. 855 if (auto *Var = dyn_cast<llvm::GlobalVariable>(GV)) 856 if (!Var->isThreadLocal() && 857 (RM == llvm::Reloc::Static || CGOpts.PIECopyRelocations)) 858 return true; 859 860 // If we can use a plt entry as the symbol address we can assume it 861 // is local. 862 // FIXME: This should work for PIE, but the gold linker doesn't support it. 863 if (isa<llvm::Function>(GV) && !CGOpts.NoPLT && RM == llvm::Reloc::Static) 864 return true; 865 866 // Otherwise don't assue it is local. 867 return false; 868 } 869 870 void CodeGenModule::setDSOLocal(llvm::GlobalValue *GV) const { 871 GV->setDSOLocal(shouldAssumeDSOLocal(*this, GV)); 872 } 873 874 void CodeGenModule::setDLLImportDLLExport(llvm::GlobalValue *GV, 875 GlobalDecl GD) const { 876 const auto *D = dyn_cast<NamedDecl>(GD.getDecl()); 877 // C++ destructors have a few C++ ABI specific special cases. 878 if (const auto *Dtor = dyn_cast_or_null<CXXDestructorDecl>(D)) { 879 getCXXABI().setCXXDestructorDLLStorage(GV, Dtor, GD.getDtorType()); 880 return; 881 } 882 setDLLImportDLLExport(GV, D); 883 } 884 885 void CodeGenModule::setDLLImportDLLExport(llvm::GlobalValue *GV, 886 const NamedDecl *D) const { 887 if (D && D->isExternallyVisible()) { 888 if (D->hasAttr<DLLImportAttr>()) 889 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass); 890 else if (D->hasAttr<DLLExportAttr>() && !GV->isDeclarationForLinker()) 891 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass); 892 } 893 } 894 895 void CodeGenModule::setGVProperties(llvm::GlobalValue *GV, 896 GlobalDecl GD) const { 897 setDLLImportDLLExport(GV, GD); 898 setGVPropertiesAux(GV, dyn_cast<NamedDecl>(GD.getDecl())); 899 } 900 901 void CodeGenModule::setGVProperties(llvm::GlobalValue *GV, 902 const NamedDecl *D) const { 903 setDLLImportDLLExport(GV, D); 904 setGVPropertiesAux(GV, D); 905 } 906 907 void CodeGenModule::setGVPropertiesAux(llvm::GlobalValue *GV, 908 const NamedDecl *D) const { 909 setGlobalVisibility(GV, D); 910 setDSOLocal(GV); 911 GV->setPartition(CodeGenOpts.SymbolPartition); 912 } 913 914 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(StringRef S) { 915 return llvm::StringSwitch<llvm::GlobalVariable::ThreadLocalMode>(S) 916 .Case("global-dynamic", llvm::GlobalVariable::GeneralDynamicTLSModel) 917 .Case("local-dynamic", llvm::GlobalVariable::LocalDynamicTLSModel) 918 .Case("initial-exec", llvm::GlobalVariable::InitialExecTLSModel) 919 .Case("local-exec", llvm::GlobalVariable::LocalExecTLSModel); 920 } 921 922 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel( 923 CodeGenOptions::TLSModel M) { 924 switch (M) { 925 case CodeGenOptions::GeneralDynamicTLSModel: 926 return llvm::GlobalVariable::GeneralDynamicTLSModel; 927 case CodeGenOptions::LocalDynamicTLSModel: 928 return llvm::GlobalVariable::LocalDynamicTLSModel; 929 case CodeGenOptions::InitialExecTLSModel: 930 return llvm::GlobalVariable::InitialExecTLSModel; 931 case CodeGenOptions::LocalExecTLSModel: 932 return llvm::GlobalVariable::LocalExecTLSModel; 933 } 934 llvm_unreachable("Invalid TLS model!"); 935 } 936 937 void CodeGenModule::setTLSMode(llvm::GlobalValue *GV, const VarDecl &D) const { 938 assert(D.getTLSKind() && "setting TLS mode on non-TLS var!"); 939 940 llvm::GlobalValue::ThreadLocalMode TLM; 941 TLM = GetLLVMTLSModel(CodeGenOpts.getDefaultTLSModel()); 942 943 // Override the TLS model if it is explicitly specified. 944 if (const TLSModelAttr *Attr = D.getAttr<TLSModelAttr>()) { 945 TLM = GetLLVMTLSModel(Attr->getModel()); 946 } 947 948 GV->setThreadLocalMode(TLM); 949 } 950 951 static std::string getCPUSpecificMangling(const CodeGenModule &CGM, 952 StringRef Name) { 953 const TargetInfo &Target = CGM.getTarget(); 954 return (Twine('.') + Twine(Target.CPUSpecificManglingCharacter(Name))).str(); 955 } 956 957 static void AppendCPUSpecificCPUDispatchMangling(const CodeGenModule &CGM, 958 const CPUSpecificAttr *Attr, 959 unsigned CPUIndex, 960 raw_ostream &Out) { 961 // cpu_specific gets the current name, dispatch gets the resolver if IFunc is 962 // supported. 963 if (Attr) 964 Out << getCPUSpecificMangling(CGM, Attr->getCPUName(CPUIndex)->getName()); 965 else if (CGM.getTarget().supportsIFunc()) 966 Out << ".resolver"; 967 } 968 969 static void AppendTargetMangling(const CodeGenModule &CGM, 970 const TargetAttr *Attr, raw_ostream &Out) { 971 if (Attr->isDefaultVersion()) 972 return; 973 974 Out << '.'; 975 const TargetInfo &Target = CGM.getTarget(); 976 ParsedTargetAttr Info = 977 Attr->parse([&Target](StringRef LHS, StringRef RHS) { 978 // Multiversioning doesn't allow "no-${feature}", so we can 979 // only have "+" prefixes here. 980 assert(LHS.startswith("+") && RHS.startswith("+") && 981 "Features should always have a prefix."); 982 return Target.multiVersionSortPriority(LHS.substr(1)) > 983 Target.multiVersionSortPriority(RHS.substr(1)); 984 }); 985 986 bool IsFirst = true; 987 988 if (!Info.Architecture.empty()) { 989 IsFirst = false; 990 Out << "arch_" << Info.Architecture; 991 } 992 993 for (StringRef Feat : Info.Features) { 994 if (!IsFirst) 995 Out << '_'; 996 IsFirst = false; 997 Out << Feat.substr(1); 998 } 999 } 1000 1001 static std::string getMangledNameImpl(const CodeGenModule &CGM, GlobalDecl GD, 1002 const NamedDecl *ND, 1003 bool OmitMultiVersionMangling = false) { 1004 SmallString<256> Buffer; 1005 llvm::raw_svector_ostream Out(Buffer); 1006 MangleContext &MC = CGM.getCXXABI().getMangleContext(); 1007 if (MC.shouldMangleDeclName(ND)) { 1008 llvm::raw_svector_ostream Out(Buffer); 1009 if (const auto *D = dyn_cast<CXXConstructorDecl>(ND)) 1010 MC.mangleCXXCtor(D, GD.getCtorType(), Out); 1011 else if (const auto *D = dyn_cast<CXXDestructorDecl>(ND)) 1012 MC.mangleCXXDtor(D, GD.getDtorType(), Out); 1013 else 1014 MC.mangleName(ND, Out); 1015 } else { 1016 IdentifierInfo *II = ND->getIdentifier(); 1017 assert(II && "Attempt to mangle unnamed decl."); 1018 const auto *FD = dyn_cast<FunctionDecl>(ND); 1019 1020 if (FD && 1021 FD->getType()->castAs<FunctionType>()->getCallConv() == CC_X86RegCall) { 1022 llvm::raw_svector_ostream Out(Buffer); 1023 Out << "__regcall3__" << II->getName(); 1024 } else { 1025 Out << II->getName(); 1026 } 1027 } 1028 1029 if (const auto *FD = dyn_cast<FunctionDecl>(ND)) 1030 if (FD->isMultiVersion() && !OmitMultiVersionMangling) { 1031 switch (FD->getMultiVersionKind()) { 1032 case MultiVersionKind::CPUDispatch: 1033 case MultiVersionKind::CPUSpecific: 1034 AppendCPUSpecificCPUDispatchMangling(CGM, 1035 FD->getAttr<CPUSpecificAttr>(), 1036 GD.getMultiVersionIndex(), Out); 1037 break; 1038 case MultiVersionKind::Target: 1039 AppendTargetMangling(CGM, FD->getAttr<TargetAttr>(), Out); 1040 break; 1041 case MultiVersionKind::None: 1042 llvm_unreachable("None multiversion type isn't valid here"); 1043 } 1044 } 1045 1046 return Out.str(); 1047 } 1048 1049 void CodeGenModule::UpdateMultiVersionNames(GlobalDecl GD, 1050 const FunctionDecl *FD) { 1051 if (!FD->isMultiVersion()) 1052 return; 1053 1054 // Get the name of what this would be without the 'target' attribute. This 1055 // allows us to lookup the version that was emitted when this wasn't a 1056 // multiversion function. 1057 std::string NonTargetName = 1058 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true); 1059 GlobalDecl OtherGD; 1060 if (lookupRepresentativeDecl(NonTargetName, OtherGD)) { 1061 assert(OtherGD.getCanonicalDecl() 1062 .getDecl() 1063 ->getAsFunction() 1064 ->isMultiVersion() && 1065 "Other GD should now be a multiversioned function"); 1066 // OtherFD is the version of this function that was mangled BEFORE 1067 // becoming a MultiVersion function. It potentially needs to be updated. 1068 const FunctionDecl *OtherFD = OtherGD.getCanonicalDecl() 1069 .getDecl() 1070 ->getAsFunction() 1071 ->getMostRecentDecl(); 1072 std::string OtherName = getMangledNameImpl(*this, OtherGD, OtherFD); 1073 // This is so that if the initial version was already the 'default' 1074 // version, we don't try to update it. 1075 if (OtherName != NonTargetName) { 1076 // Remove instead of erase, since others may have stored the StringRef 1077 // to this. 1078 const auto ExistingRecord = Manglings.find(NonTargetName); 1079 if (ExistingRecord != std::end(Manglings)) 1080 Manglings.remove(&(*ExistingRecord)); 1081 auto Result = Manglings.insert(std::make_pair(OtherName, OtherGD)); 1082 MangledDeclNames[OtherGD.getCanonicalDecl()] = Result.first->first(); 1083 if (llvm::GlobalValue *Entry = GetGlobalValue(NonTargetName)) 1084 Entry->setName(OtherName); 1085 } 1086 } 1087 } 1088 1089 StringRef CodeGenModule::getMangledName(GlobalDecl GD) { 1090 GlobalDecl CanonicalGD = GD.getCanonicalDecl(); 1091 1092 // Some ABIs don't have constructor variants. Make sure that base and 1093 // complete constructors get mangled the same. 1094 if (const auto *CD = dyn_cast<CXXConstructorDecl>(CanonicalGD.getDecl())) { 1095 if (!getTarget().getCXXABI().hasConstructorVariants()) { 1096 CXXCtorType OrigCtorType = GD.getCtorType(); 1097 assert(OrigCtorType == Ctor_Base || OrigCtorType == Ctor_Complete); 1098 if (OrigCtorType == Ctor_Base) 1099 CanonicalGD = GlobalDecl(CD, Ctor_Complete); 1100 } 1101 } 1102 1103 auto FoundName = MangledDeclNames.find(CanonicalGD); 1104 if (FoundName != MangledDeclNames.end()) 1105 return FoundName->second; 1106 1107 // Keep the first result in the case of a mangling collision. 1108 const auto *ND = cast<NamedDecl>(GD.getDecl()); 1109 std::string MangledName = getMangledNameImpl(*this, GD, ND); 1110 1111 // Adjust kernel stub mangling as we may need to be able to differentiate 1112 // them from the kernel itself (e.g., for HIP). 1113 if (auto *FD = dyn_cast<FunctionDecl>(GD.getDecl())) 1114 if (!getLangOpts().CUDAIsDevice && FD->hasAttr<CUDAGlobalAttr>()) 1115 MangledName = getCUDARuntime().getDeviceStubName(MangledName); 1116 1117 auto Result = Manglings.insert(std::make_pair(MangledName, GD)); 1118 return MangledDeclNames[CanonicalGD] = Result.first->first(); 1119 } 1120 1121 StringRef CodeGenModule::getBlockMangledName(GlobalDecl GD, 1122 const BlockDecl *BD) { 1123 MangleContext &MangleCtx = getCXXABI().getMangleContext(); 1124 const Decl *D = GD.getDecl(); 1125 1126 SmallString<256> Buffer; 1127 llvm::raw_svector_ostream Out(Buffer); 1128 if (!D) 1129 MangleCtx.mangleGlobalBlock(BD, 1130 dyn_cast_or_null<VarDecl>(initializedGlobalDecl.getDecl()), Out); 1131 else if (const auto *CD = dyn_cast<CXXConstructorDecl>(D)) 1132 MangleCtx.mangleCtorBlock(CD, GD.getCtorType(), BD, Out); 1133 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(D)) 1134 MangleCtx.mangleDtorBlock(DD, GD.getDtorType(), BD, Out); 1135 else 1136 MangleCtx.mangleBlock(cast<DeclContext>(D), BD, Out); 1137 1138 auto Result = Manglings.insert(std::make_pair(Out.str(), BD)); 1139 return Result.first->first(); 1140 } 1141 1142 llvm::GlobalValue *CodeGenModule::GetGlobalValue(StringRef Name) { 1143 return getModule().getNamedValue(Name); 1144 } 1145 1146 /// AddGlobalCtor - Add a function to the list that will be called before 1147 /// main() runs. 1148 void CodeGenModule::AddGlobalCtor(llvm::Function *Ctor, int Priority, 1149 llvm::Constant *AssociatedData) { 1150 // FIXME: Type coercion of void()* types. 1151 GlobalCtors.push_back(Structor(Priority, Ctor, AssociatedData)); 1152 } 1153 1154 /// AddGlobalDtor - Add a function to the list that will be called 1155 /// when the module is unloaded. 1156 void CodeGenModule::AddGlobalDtor(llvm::Function *Dtor, int Priority) { 1157 if (CodeGenOpts.RegisterGlobalDtorsWithAtExit) { 1158 DtorsUsingAtExit[Priority].push_back(Dtor); 1159 return; 1160 } 1161 1162 // FIXME: Type coercion of void()* types. 1163 GlobalDtors.push_back(Structor(Priority, Dtor, nullptr)); 1164 } 1165 1166 void CodeGenModule::EmitCtorList(CtorList &Fns, const char *GlobalName) { 1167 if (Fns.empty()) return; 1168 1169 // Ctor function type is void()*. 1170 llvm::FunctionType* CtorFTy = llvm::FunctionType::get(VoidTy, false); 1171 llvm::Type *CtorPFTy = llvm::PointerType::get(CtorFTy, 1172 TheModule.getDataLayout().getProgramAddressSpace()); 1173 1174 // Get the type of a ctor entry, { i32, void ()*, i8* }. 1175 llvm::StructType *CtorStructTy = llvm::StructType::get( 1176 Int32Ty, CtorPFTy, VoidPtrTy); 1177 1178 // Construct the constructor and destructor arrays. 1179 ConstantInitBuilder builder(*this); 1180 auto ctors = builder.beginArray(CtorStructTy); 1181 for (const auto &I : Fns) { 1182 auto ctor = ctors.beginStruct(CtorStructTy); 1183 ctor.addInt(Int32Ty, I.Priority); 1184 ctor.add(llvm::ConstantExpr::getBitCast(I.Initializer, CtorPFTy)); 1185 if (I.AssociatedData) 1186 ctor.add(llvm::ConstantExpr::getBitCast(I.AssociatedData, VoidPtrTy)); 1187 else 1188 ctor.addNullPointer(VoidPtrTy); 1189 ctor.finishAndAddTo(ctors); 1190 } 1191 1192 auto list = 1193 ctors.finishAndCreateGlobal(GlobalName, getPointerAlign(), 1194 /*constant*/ false, 1195 llvm::GlobalValue::AppendingLinkage); 1196 1197 // The LTO linker doesn't seem to like it when we set an alignment 1198 // on appending variables. Take it off as a workaround. 1199 list->setAlignment(llvm::None); 1200 1201 Fns.clear(); 1202 } 1203 1204 llvm::GlobalValue::LinkageTypes 1205 CodeGenModule::getFunctionLinkage(GlobalDecl GD) { 1206 const auto *D = cast<FunctionDecl>(GD.getDecl()); 1207 1208 GVALinkage Linkage = getContext().GetGVALinkageForFunction(D); 1209 1210 if (const auto *Dtor = dyn_cast<CXXDestructorDecl>(D)) 1211 return getCXXABI().getCXXDestructorLinkage(Linkage, Dtor, GD.getDtorType()); 1212 1213 if (isa<CXXConstructorDecl>(D) && 1214 cast<CXXConstructorDecl>(D)->isInheritingConstructor() && 1215 Context.getTargetInfo().getCXXABI().isMicrosoft()) { 1216 // Our approach to inheriting constructors is fundamentally different from 1217 // that used by the MS ABI, so keep our inheriting constructor thunks 1218 // internal rather than trying to pick an unambiguous mangling for them. 1219 return llvm::GlobalValue::InternalLinkage; 1220 } 1221 1222 return getLLVMLinkageForDeclarator(D, Linkage, /*IsConstantVariable=*/false); 1223 } 1224 1225 llvm::ConstantInt *CodeGenModule::CreateCrossDsoCfiTypeId(llvm::Metadata *MD) { 1226 llvm::MDString *MDS = dyn_cast<llvm::MDString>(MD); 1227 if (!MDS) return nullptr; 1228 1229 return llvm::ConstantInt::get(Int64Ty, llvm::MD5Hash(MDS->getString())); 1230 } 1231 1232 void CodeGenModule::SetLLVMFunctionAttributes(GlobalDecl GD, 1233 const CGFunctionInfo &Info, 1234 llvm::Function *F) { 1235 unsigned CallingConv; 1236 llvm::AttributeList PAL; 1237 ConstructAttributeList(F->getName(), Info, GD, PAL, CallingConv, false); 1238 F->setAttributes(PAL); 1239 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv)); 1240 } 1241 1242 static void removeImageAccessQualifier(std::string& TyName) { 1243 std::string ReadOnlyQual("__read_only"); 1244 std::string::size_type ReadOnlyPos = TyName.find(ReadOnlyQual); 1245 if (ReadOnlyPos != std::string::npos) 1246 // "+ 1" for the space after access qualifier. 1247 TyName.erase(ReadOnlyPos, ReadOnlyQual.size() + 1); 1248 else { 1249 std::string WriteOnlyQual("__write_only"); 1250 std::string::size_type WriteOnlyPos = TyName.find(WriteOnlyQual); 1251 if (WriteOnlyPos != std::string::npos) 1252 TyName.erase(WriteOnlyPos, WriteOnlyQual.size() + 1); 1253 else { 1254 std::string ReadWriteQual("__read_write"); 1255 std::string::size_type ReadWritePos = TyName.find(ReadWriteQual); 1256 if (ReadWritePos != std::string::npos) 1257 TyName.erase(ReadWritePos, ReadWriteQual.size() + 1); 1258 } 1259 } 1260 } 1261 1262 // Returns the address space id that should be produced to the 1263 // kernel_arg_addr_space metadata. This is always fixed to the ids 1264 // as specified in the SPIR 2.0 specification in order to differentiate 1265 // for example in clGetKernelArgInfo() implementation between the address 1266 // spaces with targets without unique mapping to the OpenCL address spaces 1267 // (basically all single AS CPUs). 1268 static unsigned ArgInfoAddressSpace(LangAS AS) { 1269 switch (AS) { 1270 case LangAS::opencl_global: return 1; 1271 case LangAS::opencl_constant: return 2; 1272 case LangAS::opencl_local: return 3; 1273 case LangAS::opencl_generic: return 4; // Not in SPIR 2.0 specs. 1274 default: 1275 return 0; // Assume private. 1276 } 1277 } 1278 1279 void CodeGenModule::GenOpenCLArgMetadata(llvm::Function *Fn, 1280 const FunctionDecl *FD, 1281 CodeGenFunction *CGF) { 1282 assert(((FD && CGF) || (!FD && !CGF)) && 1283 "Incorrect use - FD and CGF should either be both null or not!"); 1284 // Create MDNodes that represent the kernel arg metadata. 1285 // Each MDNode is a list in the form of "key", N number of values which is 1286 // the same number of values as their are kernel arguments. 1287 1288 const PrintingPolicy &Policy = Context.getPrintingPolicy(); 1289 1290 // MDNode for the kernel argument address space qualifiers. 1291 SmallVector<llvm::Metadata *, 8> addressQuals; 1292 1293 // MDNode for the kernel argument access qualifiers (images only). 1294 SmallVector<llvm::Metadata *, 8> accessQuals; 1295 1296 // MDNode for the kernel argument type names. 1297 SmallVector<llvm::Metadata *, 8> argTypeNames; 1298 1299 // MDNode for the kernel argument base type names. 1300 SmallVector<llvm::Metadata *, 8> argBaseTypeNames; 1301 1302 // MDNode for the kernel argument type qualifiers. 1303 SmallVector<llvm::Metadata *, 8> argTypeQuals; 1304 1305 // MDNode for the kernel argument names. 1306 SmallVector<llvm::Metadata *, 8> argNames; 1307 1308 if (FD && CGF) 1309 for (unsigned i = 0, e = FD->getNumParams(); i != e; ++i) { 1310 const ParmVarDecl *parm = FD->getParamDecl(i); 1311 QualType ty = parm->getType(); 1312 std::string typeQuals; 1313 1314 if (ty->isPointerType()) { 1315 QualType pointeeTy = ty->getPointeeType(); 1316 1317 // Get address qualifier. 1318 addressQuals.push_back( 1319 llvm::ConstantAsMetadata::get(CGF->Builder.getInt32( 1320 ArgInfoAddressSpace(pointeeTy.getAddressSpace())))); 1321 1322 // Get argument type name. 1323 std::string typeName = 1324 pointeeTy.getUnqualifiedType().getAsString(Policy) + "*"; 1325 1326 // Turn "unsigned type" to "utype" 1327 std::string::size_type pos = typeName.find("unsigned"); 1328 if (pointeeTy.isCanonical() && pos != std::string::npos) 1329 typeName.erase(pos + 1, 8); 1330 1331 argTypeNames.push_back(llvm::MDString::get(VMContext, typeName)); 1332 1333 std::string baseTypeName = 1334 pointeeTy.getUnqualifiedType().getCanonicalType().getAsString( 1335 Policy) + 1336 "*"; 1337 1338 // Turn "unsigned type" to "utype" 1339 pos = baseTypeName.find("unsigned"); 1340 if (pos != std::string::npos) 1341 baseTypeName.erase(pos + 1, 8); 1342 1343 argBaseTypeNames.push_back( 1344 llvm::MDString::get(VMContext, baseTypeName)); 1345 1346 // Get argument type qualifiers: 1347 if (ty.isRestrictQualified()) 1348 typeQuals = "restrict"; 1349 if (pointeeTy.isConstQualified() || 1350 (pointeeTy.getAddressSpace() == LangAS::opencl_constant)) 1351 typeQuals += typeQuals.empty() ? "const" : " const"; 1352 if (pointeeTy.isVolatileQualified()) 1353 typeQuals += typeQuals.empty() ? "volatile" : " volatile"; 1354 } else { 1355 uint32_t AddrSpc = 0; 1356 bool isPipe = ty->isPipeType(); 1357 if (ty->isImageType() || isPipe) 1358 AddrSpc = ArgInfoAddressSpace(LangAS::opencl_global); 1359 1360 addressQuals.push_back( 1361 llvm::ConstantAsMetadata::get(CGF->Builder.getInt32(AddrSpc))); 1362 1363 // Get argument type name. 1364 std::string typeName; 1365 if (isPipe) 1366 typeName = ty.getCanonicalType() 1367 ->getAs<PipeType>() 1368 ->getElementType() 1369 .getAsString(Policy); 1370 else 1371 typeName = ty.getUnqualifiedType().getAsString(Policy); 1372 1373 // Turn "unsigned type" to "utype" 1374 std::string::size_type pos = typeName.find("unsigned"); 1375 if (ty.isCanonical() && pos != std::string::npos) 1376 typeName.erase(pos + 1, 8); 1377 1378 std::string baseTypeName; 1379 if (isPipe) 1380 baseTypeName = ty.getCanonicalType() 1381 ->getAs<PipeType>() 1382 ->getElementType() 1383 .getCanonicalType() 1384 .getAsString(Policy); 1385 else 1386 baseTypeName = 1387 ty.getUnqualifiedType().getCanonicalType().getAsString(Policy); 1388 1389 // Remove access qualifiers on images 1390 // (as they are inseparable from type in clang implementation, 1391 // but OpenCL spec provides a special query to get access qualifier 1392 // via clGetKernelArgInfo with CL_KERNEL_ARG_ACCESS_QUALIFIER): 1393 if (ty->isImageType()) { 1394 removeImageAccessQualifier(typeName); 1395 removeImageAccessQualifier(baseTypeName); 1396 } 1397 1398 argTypeNames.push_back(llvm::MDString::get(VMContext, typeName)); 1399 1400 // Turn "unsigned type" to "utype" 1401 pos = baseTypeName.find("unsigned"); 1402 if (pos != std::string::npos) 1403 baseTypeName.erase(pos + 1, 8); 1404 1405 argBaseTypeNames.push_back( 1406 llvm::MDString::get(VMContext, baseTypeName)); 1407 1408 if (isPipe) 1409 typeQuals = "pipe"; 1410 } 1411 1412 argTypeQuals.push_back(llvm::MDString::get(VMContext, typeQuals)); 1413 1414 // Get image and pipe access qualifier: 1415 if (ty->isImageType() || ty->isPipeType()) { 1416 const Decl *PDecl = parm; 1417 if (auto *TD = dyn_cast<TypedefType>(ty)) 1418 PDecl = TD->getDecl(); 1419 const OpenCLAccessAttr *A = PDecl->getAttr<OpenCLAccessAttr>(); 1420 if (A && A->isWriteOnly()) 1421 accessQuals.push_back(llvm::MDString::get(VMContext, "write_only")); 1422 else if (A && A->isReadWrite()) 1423 accessQuals.push_back(llvm::MDString::get(VMContext, "read_write")); 1424 else 1425 accessQuals.push_back(llvm::MDString::get(VMContext, "read_only")); 1426 } else 1427 accessQuals.push_back(llvm::MDString::get(VMContext, "none")); 1428 1429 // Get argument name. 1430 argNames.push_back(llvm::MDString::get(VMContext, parm->getName())); 1431 } 1432 1433 Fn->setMetadata("kernel_arg_addr_space", 1434 llvm::MDNode::get(VMContext, addressQuals)); 1435 Fn->setMetadata("kernel_arg_access_qual", 1436 llvm::MDNode::get(VMContext, accessQuals)); 1437 Fn->setMetadata("kernel_arg_type", 1438 llvm::MDNode::get(VMContext, argTypeNames)); 1439 Fn->setMetadata("kernel_arg_base_type", 1440 llvm::MDNode::get(VMContext, argBaseTypeNames)); 1441 Fn->setMetadata("kernel_arg_type_qual", 1442 llvm::MDNode::get(VMContext, argTypeQuals)); 1443 if (getCodeGenOpts().EmitOpenCLArgMetadata) 1444 Fn->setMetadata("kernel_arg_name", 1445 llvm::MDNode::get(VMContext, argNames)); 1446 } 1447 1448 /// Determines whether the language options require us to model 1449 /// unwind exceptions. We treat -fexceptions as mandating this 1450 /// except under the fragile ObjC ABI with only ObjC exceptions 1451 /// enabled. This means, for example, that C with -fexceptions 1452 /// enables this. 1453 static bool hasUnwindExceptions(const LangOptions &LangOpts) { 1454 // If exceptions are completely disabled, obviously this is false. 1455 if (!LangOpts.Exceptions) return false; 1456 1457 // If C++ exceptions are enabled, this is true. 1458 if (LangOpts.CXXExceptions) return true; 1459 1460 // If ObjC exceptions are enabled, this depends on the ABI. 1461 if (LangOpts.ObjCExceptions) { 1462 return LangOpts.ObjCRuntime.hasUnwindExceptions(); 1463 } 1464 1465 return true; 1466 } 1467 1468 static bool requiresMemberFunctionPointerTypeMetadata(CodeGenModule &CGM, 1469 const CXXMethodDecl *MD) { 1470 // Check that the type metadata can ever actually be used by a call. 1471 if (!CGM.getCodeGenOpts().LTOUnit || 1472 !CGM.HasHiddenLTOVisibility(MD->getParent())) 1473 return false; 1474 1475 // Only functions whose address can be taken with a member function pointer 1476 // need this sort of type metadata. 1477 return !MD->isStatic() && !MD->isVirtual() && !isa<CXXConstructorDecl>(MD) && 1478 !isa<CXXDestructorDecl>(MD); 1479 } 1480 1481 std::vector<const CXXRecordDecl *> 1482 CodeGenModule::getMostBaseClasses(const CXXRecordDecl *RD) { 1483 llvm::SetVector<const CXXRecordDecl *> MostBases; 1484 1485 std::function<void (const CXXRecordDecl *)> CollectMostBases; 1486 CollectMostBases = [&](const CXXRecordDecl *RD) { 1487 if (RD->getNumBases() == 0) 1488 MostBases.insert(RD); 1489 for (const CXXBaseSpecifier &B : RD->bases()) 1490 CollectMostBases(B.getType()->getAsCXXRecordDecl()); 1491 }; 1492 CollectMostBases(RD); 1493 return MostBases.takeVector(); 1494 } 1495 1496 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D, 1497 llvm::Function *F) { 1498 llvm::AttrBuilder B; 1499 1500 if (CodeGenOpts.UnwindTables) 1501 B.addAttribute(llvm::Attribute::UWTable); 1502 1503 if (!hasUnwindExceptions(LangOpts)) 1504 B.addAttribute(llvm::Attribute::NoUnwind); 1505 1506 if (!D || !D->hasAttr<NoStackProtectorAttr>()) { 1507 if (LangOpts.getStackProtector() == LangOptions::SSPOn) 1508 B.addAttribute(llvm::Attribute::StackProtect); 1509 else if (LangOpts.getStackProtector() == LangOptions::SSPStrong) 1510 B.addAttribute(llvm::Attribute::StackProtectStrong); 1511 else if (LangOpts.getStackProtector() == LangOptions::SSPReq) 1512 B.addAttribute(llvm::Attribute::StackProtectReq); 1513 } 1514 1515 if (!D) { 1516 // If we don't have a declaration to control inlining, the function isn't 1517 // explicitly marked as alwaysinline for semantic reasons, and inlining is 1518 // disabled, mark the function as noinline. 1519 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline) && 1520 CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining) 1521 B.addAttribute(llvm::Attribute::NoInline); 1522 1523 F->addAttributes(llvm::AttributeList::FunctionIndex, B); 1524 return; 1525 } 1526 1527 // Track whether we need to add the optnone LLVM attribute, 1528 // starting with the default for this optimization level. 1529 bool ShouldAddOptNone = 1530 !CodeGenOpts.DisableO0ImplyOptNone && CodeGenOpts.OptimizationLevel == 0; 1531 // We can't add optnone in the following cases, it won't pass the verifier. 1532 ShouldAddOptNone &= !D->hasAttr<MinSizeAttr>(); 1533 ShouldAddOptNone &= !D->hasAttr<AlwaysInlineAttr>(); 1534 1535 // Add optnone, but do so only if the function isn't always_inline. 1536 if ((ShouldAddOptNone || D->hasAttr<OptimizeNoneAttr>()) && 1537 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) { 1538 B.addAttribute(llvm::Attribute::OptimizeNone); 1539 1540 // OptimizeNone implies noinline; we should not be inlining such functions. 1541 B.addAttribute(llvm::Attribute::NoInline); 1542 1543 // We still need to handle naked functions even though optnone subsumes 1544 // much of their semantics. 1545 if (D->hasAttr<NakedAttr>()) 1546 B.addAttribute(llvm::Attribute::Naked); 1547 1548 // OptimizeNone wins over OptimizeForSize and MinSize. 1549 F->removeFnAttr(llvm::Attribute::OptimizeForSize); 1550 F->removeFnAttr(llvm::Attribute::MinSize); 1551 } else if (D->hasAttr<NakedAttr>()) { 1552 // Naked implies noinline: we should not be inlining such functions. 1553 B.addAttribute(llvm::Attribute::Naked); 1554 B.addAttribute(llvm::Attribute::NoInline); 1555 } else if (D->hasAttr<NoDuplicateAttr>()) { 1556 B.addAttribute(llvm::Attribute::NoDuplicate); 1557 } else if (D->hasAttr<NoInlineAttr>() && !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) { 1558 // Add noinline if the function isn't always_inline. 1559 B.addAttribute(llvm::Attribute::NoInline); 1560 } else if (D->hasAttr<AlwaysInlineAttr>() && 1561 !F->hasFnAttribute(llvm::Attribute::NoInline)) { 1562 // (noinline wins over always_inline, and we can't specify both in IR) 1563 B.addAttribute(llvm::Attribute::AlwaysInline); 1564 } else if (CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining) { 1565 // If we're not inlining, then force everything that isn't always_inline to 1566 // carry an explicit noinline attribute. 1567 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline)) 1568 B.addAttribute(llvm::Attribute::NoInline); 1569 } else { 1570 // Otherwise, propagate the inline hint attribute and potentially use its 1571 // absence to mark things as noinline. 1572 if (auto *FD = dyn_cast<FunctionDecl>(D)) { 1573 // Search function and template pattern redeclarations for inline. 1574 auto CheckForInline = [](const FunctionDecl *FD) { 1575 auto CheckRedeclForInline = [](const FunctionDecl *Redecl) { 1576 return Redecl->isInlineSpecified(); 1577 }; 1578 if (any_of(FD->redecls(), CheckRedeclForInline)) 1579 return true; 1580 const FunctionDecl *Pattern = FD->getTemplateInstantiationPattern(); 1581 if (!Pattern) 1582 return false; 1583 return any_of(Pattern->redecls(), CheckRedeclForInline); 1584 }; 1585 if (CheckForInline(FD)) { 1586 B.addAttribute(llvm::Attribute::InlineHint); 1587 } else if (CodeGenOpts.getInlining() == 1588 CodeGenOptions::OnlyHintInlining && 1589 !FD->isInlined() && 1590 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) { 1591 B.addAttribute(llvm::Attribute::NoInline); 1592 } 1593 } 1594 } 1595 1596 // Add other optimization related attributes if we are optimizing this 1597 // function. 1598 if (!D->hasAttr<OptimizeNoneAttr>()) { 1599 if (D->hasAttr<ColdAttr>()) { 1600 if (!ShouldAddOptNone) 1601 B.addAttribute(llvm::Attribute::OptimizeForSize); 1602 B.addAttribute(llvm::Attribute::Cold); 1603 } 1604 1605 if (D->hasAttr<MinSizeAttr>()) 1606 B.addAttribute(llvm::Attribute::MinSize); 1607 } 1608 1609 F->addAttributes(llvm::AttributeList::FunctionIndex, B); 1610 1611 unsigned alignment = D->getMaxAlignment() / Context.getCharWidth(); 1612 if (alignment) 1613 F->setAlignment(llvm::Align(alignment)); 1614 1615 if (!D->hasAttr<AlignedAttr>()) 1616 if (LangOpts.FunctionAlignment) 1617 F->setAlignment(llvm::Align(1ull << LangOpts.FunctionAlignment)); 1618 1619 // Some C++ ABIs require 2-byte alignment for member functions, in order to 1620 // reserve a bit for differentiating between virtual and non-virtual member 1621 // functions. If the current target's C++ ABI requires this and this is a 1622 // member function, set its alignment accordingly. 1623 if (getTarget().getCXXABI().areMemberFunctionsAligned()) { 1624 if (F->getAlignment() < 2 && isa<CXXMethodDecl>(D)) 1625 F->setAlignment(llvm::Align(2)); 1626 } 1627 1628 // In the cross-dso CFI mode with canonical jump tables, we want !type 1629 // attributes on definitions only. 1630 if (CodeGenOpts.SanitizeCfiCrossDso && 1631 CodeGenOpts.SanitizeCfiCanonicalJumpTables) { 1632 if (auto *FD = dyn_cast<FunctionDecl>(D)) { 1633 // Skip available_externally functions. They won't be codegen'ed in the 1634 // current module anyway. 1635 if (getContext().GetGVALinkageForFunction(FD) != GVA_AvailableExternally) 1636 CreateFunctionTypeMetadataForIcall(FD, F); 1637 } 1638 } 1639 1640 // Emit type metadata on member functions for member function pointer checks. 1641 // These are only ever necessary on definitions; we're guaranteed that the 1642 // definition will be present in the LTO unit as a result of LTO visibility. 1643 auto *MD = dyn_cast<CXXMethodDecl>(D); 1644 if (MD && requiresMemberFunctionPointerTypeMetadata(*this, MD)) { 1645 for (const CXXRecordDecl *Base : getMostBaseClasses(MD->getParent())) { 1646 llvm::Metadata *Id = 1647 CreateMetadataIdentifierForType(Context.getMemberPointerType( 1648 MD->getType(), Context.getRecordType(Base).getTypePtr())); 1649 F->addTypeMetadata(0, Id); 1650 } 1651 } 1652 } 1653 1654 void CodeGenModule::SetCommonAttributes(GlobalDecl GD, llvm::GlobalValue *GV) { 1655 const Decl *D = GD.getDecl(); 1656 if (dyn_cast_or_null<NamedDecl>(D)) 1657 setGVProperties(GV, GD); 1658 else 1659 GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 1660 1661 if (D && D->hasAttr<UsedAttr>()) 1662 addUsedGlobal(GV); 1663 1664 if (CodeGenOpts.KeepStaticConsts && D && isa<VarDecl>(D)) { 1665 const auto *VD = cast<VarDecl>(D); 1666 if (VD->getType().isConstQualified() && 1667 VD->getStorageDuration() == SD_Static) 1668 addUsedGlobal(GV); 1669 } 1670 } 1671 1672 bool CodeGenModule::GetCPUAndFeaturesAttributes(GlobalDecl GD, 1673 llvm::AttrBuilder &Attrs) { 1674 // Add target-cpu and target-features attributes to functions. If 1675 // we have a decl for the function and it has a target attribute then 1676 // parse that and add it to the feature set. 1677 StringRef TargetCPU = getTarget().getTargetOpts().CPU; 1678 std::vector<std::string> Features; 1679 const auto *FD = dyn_cast_or_null<FunctionDecl>(GD.getDecl()); 1680 FD = FD ? FD->getMostRecentDecl() : FD; 1681 const auto *TD = FD ? FD->getAttr<TargetAttr>() : nullptr; 1682 const auto *SD = FD ? FD->getAttr<CPUSpecificAttr>() : nullptr; 1683 bool AddedAttr = false; 1684 if (TD || SD) { 1685 llvm::StringMap<bool> FeatureMap; 1686 getContext().getFunctionFeatureMap(FeatureMap, GD); 1687 1688 // Produce the canonical string for this set of features. 1689 for (const llvm::StringMap<bool>::value_type &Entry : FeatureMap) 1690 Features.push_back((Entry.getValue() ? "+" : "-") + Entry.getKey().str()); 1691 1692 // Now add the target-cpu and target-features to the function. 1693 // While we populated the feature map above, we still need to 1694 // get and parse the target attribute so we can get the cpu for 1695 // the function. 1696 if (TD) { 1697 ParsedTargetAttr ParsedAttr = TD->parse(); 1698 if (ParsedAttr.Architecture != "" && 1699 getTarget().isValidCPUName(ParsedAttr.Architecture)) 1700 TargetCPU = ParsedAttr.Architecture; 1701 } 1702 } else { 1703 // Otherwise just add the existing target cpu and target features to the 1704 // function. 1705 Features = getTarget().getTargetOpts().Features; 1706 } 1707 1708 if (TargetCPU != "") { 1709 Attrs.addAttribute("target-cpu", TargetCPU); 1710 AddedAttr = true; 1711 } 1712 if (!Features.empty()) { 1713 llvm::sort(Features); 1714 Attrs.addAttribute("target-features", llvm::join(Features, ",")); 1715 AddedAttr = true; 1716 } 1717 1718 return AddedAttr; 1719 } 1720 1721 void CodeGenModule::setNonAliasAttributes(GlobalDecl GD, 1722 llvm::GlobalObject *GO) { 1723 const Decl *D = GD.getDecl(); 1724 SetCommonAttributes(GD, GO); 1725 1726 if (D) { 1727 if (auto *GV = dyn_cast<llvm::GlobalVariable>(GO)) { 1728 if (auto *SA = D->getAttr<PragmaClangBSSSectionAttr>()) 1729 GV->addAttribute("bss-section", SA->getName()); 1730 if (auto *SA = D->getAttr<PragmaClangDataSectionAttr>()) 1731 GV->addAttribute("data-section", SA->getName()); 1732 if (auto *SA = D->getAttr<PragmaClangRodataSectionAttr>()) 1733 GV->addAttribute("rodata-section", SA->getName()); 1734 if (auto *SA = D->getAttr<PragmaClangRelroSectionAttr>()) 1735 GV->addAttribute("relro-section", SA->getName()); 1736 } 1737 1738 if (auto *F = dyn_cast<llvm::Function>(GO)) { 1739 if (auto *SA = D->getAttr<PragmaClangTextSectionAttr>()) 1740 if (!D->getAttr<SectionAttr>()) 1741 F->addFnAttr("implicit-section-name", SA->getName()); 1742 1743 llvm::AttrBuilder Attrs; 1744 if (GetCPUAndFeaturesAttributes(GD, Attrs)) { 1745 // We know that GetCPUAndFeaturesAttributes will always have the 1746 // newest set, since it has the newest possible FunctionDecl, so the 1747 // new ones should replace the old. 1748 F->removeFnAttr("target-cpu"); 1749 F->removeFnAttr("target-features"); 1750 F->addAttributes(llvm::AttributeList::FunctionIndex, Attrs); 1751 } 1752 } 1753 1754 if (const auto *CSA = D->getAttr<CodeSegAttr>()) 1755 GO->setSection(CSA->getName()); 1756 else if (const auto *SA = D->getAttr<SectionAttr>()) 1757 GO->setSection(SA->getName()); 1758 } 1759 1760 getTargetCodeGenInfo().setTargetAttributes(D, GO, *this); 1761 } 1762 1763 void CodeGenModule::SetInternalFunctionAttributes(GlobalDecl GD, 1764 llvm::Function *F, 1765 const CGFunctionInfo &FI) { 1766 const Decl *D = GD.getDecl(); 1767 SetLLVMFunctionAttributes(GD, FI, F); 1768 SetLLVMFunctionAttributesForDefinition(D, F); 1769 1770 F->setLinkage(llvm::Function::InternalLinkage); 1771 1772 setNonAliasAttributes(GD, F); 1773 } 1774 1775 static void setLinkageForGV(llvm::GlobalValue *GV, const NamedDecl *ND) { 1776 // Set linkage and visibility in case we never see a definition. 1777 LinkageInfo LV = ND->getLinkageAndVisibility(); 1778 // Don't set internal linkage on declarations. 1779 // "extern_weak" is overloaded in LLVM; we probably should have 1780 // separate linkage types for this. 1781 if (isExternallyVisible(LV.getLinkage()) && 1782 (ND->hasAttr<WeakAttr>() || ND->isWeakImported())) 1783 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage); 1784 } 1785 1786 void CodeGenModule::CreateFunctionTypeMetadataForIcall(const FunctionDecl *FD, 1787 llvm::Function *F) { 1788 // Only if we are checking indirect calls. 1789 if (!LangOpts.Sanitize.has(SanitizerKind::CFIICall)) 1790 return; 1791 1792 // Non-static class methods are handled via vtable or member function pointer 1793 // checks elsewhere. 1794 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 1795 return; 1796 1797 llvm::Metadata *MD = CreateMetadataIdentifierForType(FD->getType()); 1798 F->addTypeMetadata(0, MD); 1799 F->addTypeMetadata(0, CreateMetadataIdentifierGeneralized(FD->getType())); 1800 1801 // Emit a hash-based bit set entry for cross-DSO calls. 1802 if (CodeGenOpts.SanitizeCfiCrossDso) 1803 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD)) 1804 F->addTypeMetadata(0, llvm::ConstantAsMetadata::get(CrossDsoTypeId)); 1805 } 1806 1807 void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, llvm::Function *F, 1808 bool IsIncompleteFunction, 1809 bool IsThunk) { 1810 1811 if (llvm::Intrinsic::ID IID = F->getIntrinsicID()) { 1812 // If this is an intrinsic function, set the function's attributes 1813 // to the intrinsic's attributes. 1814 F->setAttributes(llvm::Intrinsic::getAttributes(getLLVMContext(), IID)); 1815 return; 1816 } 1817 1818 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 1819 1820 if (!IsIncompleteFunction) 1821 SetLLVMFunctionAttributes(GD, getTypes().arrangeGlobalDeclaration(GD), F); 1822 1823 // Add the Returned attribute for "this", except for iOS 5 and earlier 1824 // where substantial code, including the libstdc++ dylib, was compiled with 1825 // GCC and does not actually return "this". 1826 if (!IsThunk && getCXXABI().HasThisReturn(GD) && 1827 !(getTriple().isiOS() && getTriple().isOSVersionLT(6))) { 1828 assert(!F->arg_empty() && 1829 F->arg_begin()->getType() 1830 ->canLosslesslyBitCastTo(F->getReturnType()) && 1831 "unexpected this return"); 1832 F->addAttribute(1, llvm::Attribute::Returned); 1833 } 1834 1835 // Only a few attributes are set on declarations; these may later be 1836 // overridden by a definition. 1837 1838 setLinkageForGV(F, FD); 1839 setGVProperties(F, FD); 1840 1841 // Setup target-specific attributes. 1842 if (!IsIncompleteFunction && F->isDeclaration()) 1843 getTargetCodeGenInfo().setTargetAttributes(FD, F, *this); 1844 1845 if (const auto *CSA = FD->getAttr<CodeSegAttr>()) 1846 F->setSection(CSA->getName()); 1847 else if (const auto *SA = FD->getAttr<SectionAttr>()) 1848 F->setSection(SA->getName()); 1849 1850 if (FD->isInlineBuiltinDeclaration()) { 1851 F->addAttribute(llvm::AttributeList::FunctionIndex, 1852 llvm::Attribute::NoBuiltin); 1853 } 1854 1855 if (FD->isReplaceableGlobalAllocationFunction()) { 1856 // A replaceable global allocation function does not act like a builtin by 1857 // default, only if it is invoked by a new-expression or delete-expression. 1858 F->addAttribute(llvm::AttributeList::FunctionIndex, 1859 llvm::Attribute::NoBuiltin); 1860 1861 // A sane operator new returns a non-aliasing pointer. 1862 // FIXME: Also add NonNull attribute to the return value 1863 // for the non-nothrow forms? 1864 auto Kind = FD->getDeclName().getCXXOverloadedOperator(); 1865 if (getCodeGenOpts().AssumeSaneOperatorNew && 1866 (Kind == OO_New || Kind == OO_Array_New)) 1867 F->addAttribute(llvm::AttributeList::ReturnIndex, 1868 llvm::Attribute::NoAlias); 1869 } 1870 1871 if (isa<CXXConstructorDecl>(FD) || isa<CXXDestructorDecl>(FD)) 1872 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 1873 else if (const auto *MD = dyn_cast<CXXMethodDecl>(FD)) 1874 if (MD->isVirtual()) 1875 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 1876 1877 // Don't emit entries for function declarations in the cross-DSO mode. This 1878 // is handled with better precision by the receiving DSO. But if jump tables 1879 // are non-canonical then we need type metadata in order to produce the local 1880 // jump table. 1881 if (!CodeGenOpts.SanitizeCfiCrossDso || 1882 !CodeGenOpts.SanitizeCfiCanonicalJumpTables) 1883 CreateFunctionTypeMetadataForIcall(FD, F); 1884 1885 if (getLangOpts().OpenMP && FD->hasAttr<OMPDeclareSimdDeclAttr>()) 1886 getOpenMPRuntime().emitDeclareSimdFunction(FD, F); 1887 1888 if (const auto *CB = FD->getAttr<CallbackAttr>()) { 1889 // Annotate the callback behavior as metadata: 1890 // - The callback callee (as argument number). 1891 // - The callback payloads (as argument numbers). 1892 llvm::LLVMContext &Ctx = F->getContext(); 1893 llvm::MDBuilder MDB(Ctx); 1894 1895 // The payload indices are all but the first one in the encoding. The first 1896 // identifies the callback callee. 1897 int CalleeIdx = *CB->encoding_begin(); 1898 ArrayRef<int> PayloadIndices(CB->encoding_begin() + 1, CB->encoding_end()); 1899 F->addMetadata(llvm::LLVMContext::MD_callback, 1900 *llvm::MDNode::get(Ctx, {MDB.createCallbackEncoding( 1901 CalleeIdx, PayloadIndices, 1902 /* VarArgsArePassed */ false)})); 1903 } 1904 } 1905 1906 void CodeGenModule::addUsedGlobal(llvm::GlobalValue *GV) { 1907 assert(!GV->isDeclaration() && 1908 "Only globals with definition can force usage."); 1909 LLVMUsed.emplace_back(GV); 1910 } 1911 1912 void CodeGenModule::addCompilerUsedGlobal(llvm::GlobalValue *GV) { 1913 assert(!GV->isDeclaration() && 1914 "Only globals with definition can force usage."); 1915 LLVMCompilerUsed.emplace_back(GV); 1916 } 1917 1918 static void emitUsed(CodeGenModule &CGM, StringRef Name, 1919 std::vector<llvm::WeakTrackingVH> &List) { 1920 // Don't create llvm.used if there is no need. 1921 if (List.empty()) 1922 return; 1923 1924 // Convert List to what ConstantArray needs. 1925 SmallVector<llvm::Constant*, 8> UsedArray; 1926 UsedArray.resize(List.size()); 1927 for (unsigned i = 0, e = List.size(); i != e; ++i) { 1928 UsedArray[i] = 1929 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast( 1930 cast<llvm::Constant>(&*List[i]), CGM.Int8PtrTy); 1931 } 1932 1933 if (UsedArray.empty()) 1934 return; 1935 llvm::ArrayType *ATy = llvm::ArrayType::get(CGM.Int8PtrTy, UsedArray.size()); 1936 1937 auto *GV = new llvm::GlobalVariable( 1938 CGM.getModule(), ATy, false, llvm::GlobalValue::AppendingLinkage, 1939 llvm::ConstantArray::get(ATy, UsedArray), Name); 1940 1941 GV->setSection("llvm.metadata"); 1942 } 1943 1944 void CodeGenModule::emitLLVMUsed() { 1945 emitUsed(*this, "llvm.used", LLVMUsed); 1946 emitUsed(*this, "llvm.compiler.used", LLVMCompilerUsed); 1947 } 1948 1949 void CodeGenModule::AppendLinkerOptions(StringRef Opts) { 1950 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opts); 1951 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts)); 1952 } 1953 1954 void CodeGenModule::AddDetectMismatch(StringRef Name, StringRef Value) { 1955 llvm::SmallString<32> Opt; 1956 getTargetCodeGenInfo().getDetectMismatchOption(Name, Value, Opt); 1957 if (Opt.empty()) 1958 return; 1959 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt); 1960 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts)); 1961 } 1962 1963 void CodeGenModule::AddDependentLib(StringRef Lib) { 1964 auto &C = getLLVMContext(); 1965 if (getTarget().getTriple().isOSBinFormatELF()) { 1966 ELFDependentLibraries.push_back( 1967 llvm::MDNode::get(C, llvm::MDString::get(C, Lib))); 1968 return; 1969 } 1970 1971 llvm::SmallString<24> Opt; 1972 getTargetCodeGenInfo().getDependentLibraryOption(Lib, Opt); 1973 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt); 1974 LinkerOptionsMetadata.push_back(llvm::MDNode::get(C, MDOpts)); 1975 } 1976 1977 /// Add link options implied by the given module, including modules 1978 /// it depends on, using a postorder walk. 1979 static void addLinkOptionsPostorder(CodeGenModule &CGM, Module *Mod, 1980 SmallVectorImpl<llvm::MDNode *> &Metadata, 1981 llvm::SmallPtrSet<Module *, 16> &Visited) { 1982 // Import this module's parent. 1983 if (Mod->Parent && Visited.insert(Mod->Parent).second) { 1984 addLinkOptionsPostorder(CGM, Mod->Parent, Metadata, Visited); 1985 } 1986 1987 // Import this module's dependencies. 1988 for (unsigned I = Mod->Imports.size(); I > 0; --I) { 1989 if (Visited.insert(Mod->Imports[I - 1]).second) 1990 addLinkOptionsPostorder(CGM, Mod->Imports[I-1], Metadata, Visited); 1991 } 1992 1993 // Add linker options to link against the libraries/frameworks 1994 // described by this module. 1995 llvm::LLVMContext &Context = CGM.getLLVMContext(); 1996 bool IsELF = CGM.getTarget().getTriple().isOSBinFormatELF(); 1997 1998 // For modules that use export_as for linking, use that module 1999 // name instead. 2000 if (Mod->UseExportAsModuleLinkName) 2001 return; 2002 2003 for (unsigned I = Mod->LinkLibraries.size(); I > 0; --I) { 2004 // Link against a framework. Frameworks are currently Darwin only, so we 2005 // don't to ask TargetCodeGenInfo for the spelling of the linker option. 2006 if (Mod->LinkLibraries[I-1].IsFramework) { 2007 llvm::Metadata *Args[2] = { 2008 llvm::MDString::get(Context, "-framework"), 2009 llvm::MDString::get(Context, Mod->LinkLibraries[I - 1].Library)}; 2010 2011 Metadata.push_back(llvm::MDNode::get(Context, Args)); 2012 continue; 2013 } 2014 2015 // Link against a library. 2016 if (IsELF) { 2017 llvm::Metadata *Args[2] = { 2018 llvm::MDString::get(Context, "lib"), 2019 llvm::MDString::get(Context, Mod->LinkLibraries[I - 1].Library), 2020 }; 2021 Metadata.push_back(llvm::MDNode::get(Context, Args)); 2022 } else { 2023 llvm::SmallString<24> Opt; 2024 CGM.getTargetCodeGenInfo().getDependentLibraryOption( 2025 Mod->LinkLibraries[I - 1].Library, Opt); 2026 auto *OptString = llvm::MDString::get(Context, Opt); 2027 Metadata.push_back(llvm::MDNode::get(Context, OptString)); 2028 } 2029 } 2030 } 2031 2032 void CodeGenModule::EmitModuleLinkOptions() { 2033 // Collect the set of all of the modules we want to visit to emit link 2034 // options, which is essentially the imported modules and all of their 2035 // non-explicit child modules. 2036 llvm::SetVector<clang::Module *> LinkModules; 2037 llvm::SmallPtrSet<clang::Module *, 16> Visited; 2038 SmallVector<clang::Module *, 16> Stack; 2039 2040 // Seed the stack with imported modules. 2041 for (Module *M : ImportedModules) { 2042 // Do not add any link flags when an implementation TU of a module imports 2043 // a header of that same module. 2044 if (M->getTopLevelModuleName() == getLangOpts().CurrentModule && 2045 !getLangOpts().isCompilingModule()) 2046 continue; 2047 if (Visited.insert(M).second) 2048 Stack.push_back(M); 2049 } 2050 2051 // Find all of the modules to import, making a little effort to prune 2052 // non-leaf modules. 2053 while (!Stack.empty()) { 2054 clang::Module *Mod = Stack.pop_back_val(); 2055 2056 bool AnyChildren = false; 2057 2058 // Visit the submodules of this module. 2059 for (const auto &SM : Mod->submodules()) { 2060 // Skip explicit children; they need to be explicitly imported to be 2061 // linked against. 2062 if (SM->IsExplicit) 2063 continue; 2064 2065 if (Visited.insert(SM).second) { 2066 Stack.push_back(SM); 2067 AnyChildren = true; 2068 } 2069 } 2070 2071 // We didn't find any children, so add this module to the list of 2072 // modules to link against. 2073 if (!AnyChildren) { 2074 LinkModules.insert(Mod); 2075 } 2076 } 2077 2078 // Add link options for all of the imported modules in reverse topological 2079 // order. We don't do anything to try to order import link flags with respect 2080 // to linker options inserted by things like #pragma comment(). 2081 SmallVector<llvm::MDNode *, 16> MetadataArgs; 2082 Visited.clear(); 2083 for (Module *M : LinkModules) 2084 if (Visited.insert(M).second) 2085 addLinkOptionsPostorder(*this, M, MetadataArgs, Visited); 2086 std::reverse(MetadataArgs.begin(), MetadataArgs.end()); 2087 LinkerOptionsMetadata.append(MetadataArgs.begin(), MetadataArgs.end()); 2088 2089 // Add the linker options metadata flag. 2090 auto *NMD = getModule().getOrInsertNamedMetadata("llvm.linker.options"); 2091 for (auto *MD : LinkerOptionsMetadata) 2092 NMD->addOperand(MD); 2093 } 2094 2095 void CodeGenModule::EmitDeferred() { 2096 // Emit deferred declare target declarations. 2097 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd) 2098 getOpenMPRuntime().emitDeferredTargetDecls(); 2099 2100 // Emit code for any potentially referenced deferred decls. Since a 2101 // previously unused static decl may become used during the generation of code 2102 // for a static function, iterate until no changes are made. 2103 2104 if (!DeferredVTables.empty()) { 2105 EmitDeferredVTables(); 2106 2107 // Emitting a vtable doesn't directly cause more vtables to 2108 // become deferred, although it can cause functions to be 2109 // emitted that then need those vtables. 2110 assert(DeferredVTables.empty()); 2111 } 2112 2113 // Stop if we're out of both deferred vtables and deferred declarations. 2114 if (DeferredDeclsToEmit.empty()) 2115 return; 2116 2117 // Grab the list of decls to emit. If EmitGlobalDefinition schedules more 2118 // work, it will not interfere with this. 2119 std::vector<GlobalDecl> CurDeclsToEmit; 2120 CurDeclsToEmit.swap(DeferredDeclsToEmit); 2121 2122 for (GlobalDecl &D : CurDeclsToEmit) { 2123 // We should call GetAddrOfGlobal with IsForDefinition set to true in order 2124 // to get GlobalValue with exactly the type we need, not something that 2125 // might had been created for another decl with the same mangled name but 2126 // different type. 2127 llvm::GlobalValue *GV = dyn_cast<llvm::GlobalValue>( 2128 GetAddrOfGlobal(D, ForDefinition)); 2129 2130 // In case of different address spaces, we may still get a cast, even with 2131 // IsForDefinition equal to true. Query mangled names table to get 2132 // GlobalValue. 2133 if (!GV) 2134 GV = GetGlobalValue(getMangledName(D)); 2135 2136 // Make sure GetGlobalValue returned non-null. 2137 assert(GV); 2138 2139 // Check to see if we've already emitted this. This is necessary 2140 // for a couple of reasons: first, decls can end up in the 2141 // deferred-decls queue multiple times, and second, decls can end 2142 // up with definitions in unusual ways (e.g. by an extern inline 2143 // function acquiring a strong function redefinition). Just 2144 // ignore these cases. 2145 if (!GV->isDeclaration()) 2146 continue; 2147 2148 // If this is OpenMP, check if it is legal to emit this global normally. 2149 if (LangOpts.OpenMP && OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(D)) 2150 continue; 2151 2152 // Otherwise, emit the definition and move on to the next one. 2153 EmitGlobalDefinition(D, GV); 2154 2155 // If we found out that we need to emit more decls, do that recursively. 2156 // This has the advantage that the decls are emitted in a DFS and related 2157 // ones are close together, which is convenient for testing. 2158 if (!DeferredVTables.empty() || !DeferredDeclsToEmit.empty()) { 2159 EmitDeferred(); 2160 assert(DeferredVTables.empty() && DeferredDeclsToEmit.empty()); 2161 } 2162 } 2163 } 2164 2165 void CodeGenModule::EmitVTablesOpportunistically() { 2166 // Try to emit external vtables as available_externally if they have emitted 2167 // all inlined virtual functions. It runs after EmitDeferred() and therefore 2168 // is not allowed to create new references to things that need to be emitted 2169 // lazily. Note that it also uses fact that we eagerly emitting RTTI. 2170 2171 assert((OpportunisticVTables.empty() || shouldOpportunisticallyEmitVTables()) 2172 && "Only emit opportunistic vtables with optimizations"); 2173 2174 for (const CXXRecordDecl *RD : OpportunisticVTables) { 2175 assert(getVTables().isVTableExternal(RD) && 2176 "This queue should only contain external vtables"); 2177 if (getCXXABI().canSpeculativelyEmitVTable(RD)) 2178 VTables.GenerateClassData(RD); 2179 } 2180 OpportunisticVTables.clear(); 2181 } 2182 2183 void CodeGenModule::EmitGlobalAnnotations() { 2184 if (Annotations.empty()) 2185 return; 2186 2187 // Create a new global variable for the ConstantStruct in the Module. 2188 llvm::Constant *Array = llvm::ConstantArray::get(llvm::ArrayType::get( 2189 Annotations[0]->getType(), Annotations.size()), Annotations); 2190 auto *gv = new llvm::GlobalVariable(getModule(), Array->getType(), false, 2191 llvm::GlobalValue::AppendingLinkage, 2192 Array, "llvm.global.annotations"); 2193 gv->setSection(AnnotationSection); 2194 } 2195 2196 llvm::Constant *CodeGenModule::EmitAnnotationString(StringRef Str) { 2197 llvm::Constant *&AStr = AnnotationStrings[Str]; 2198 if (AStr) 2199 return AStr; 2200 2201 // Not found yet, create a new global. 2202 llvm::Constant *s = llvm::ConstantDataArray::getString(getLLVMContext(), Str); 2203 auto *gv = 2204 new llvm::GlobalVariable(getModule(), s->getType(), true, 2205 llvm::GlobalValue::PrivateLinkage, s, ".str"); 2206 gv->setSection(AnnotationSection); 2207 gv->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 2208 AStr = gv; 2209 return gv; 2210 } 2211 2212 llvm::Constant *CodeGenModule::EmitAnnotationUnit(SourceLocation Loc) { 2213 SourceManager &SM = getContext().getSourceManager(); 2214 PresumedLoc PLoc = SM.getPresumedLoc(Loc); 2215 if (PLoc.isValid()) 2216 return EmitAnnotationString(PLoc.getFilename()); 2217 return EmitAnnotationString(SM.getBufferName(Loc)); 2218 } 2219 2220 llvm::Constant *CodeGenModule::EmitAnnotationLineNo(SourceLocation L) { 2221 SourceManager &SM = getContext().getSourceManager(); 2222 PresumedLoc PLoc = SM.getPresumedLoc(L); 2223 unsigned LineNo = PLoc.isValid() ? PLoc.getLine() : 2224 SM.getExpansionLineNumber(L); 2225 return llvm::ConstantInt::get(Int32Ty, LineNo); 2226 } 2227 2228 llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV, 2229 const AnnotateAttr *AA, 2230 SourceLocation L) { 2231 // Get the globals for file name, annotation, and the line number. 2232 llvm::Constant *AnnoGV = EmitAnnotationString(AA->getAnnotation()), 2233 *UnitGV = EmitAnnotationUnit(L), 2234 *LineNoCst = EmitAnnotationLineNo(L); 2235 2236 llvm::Constant *ASZeroGV = GV; 2237 if (GV->getAddressSpace() != 0) { 2238 ASZeroGV = llvm::ConstantExpr::getAddrSpaceCast( 2239 GV, GV->getValueType()->getPointerTo(0)); 2240 } 2241 2242 // Create the ConstantStruct for the global annotation. 2243 llvm::Constant *Fields[4] = { 2244 llvm::ConstantExpr::getBitCast(ASZeroGV, Int8PtrTy), 2245 llvm::ConstantExpr::getBitCast(AnnoGV, Int8PtrTy), 2246 llvm::ConstantExpr::getBitCast(UnitGV, Int8PtrTy), 2247 LineNoCst 2248 }; 2249 return llvm::ConstantStruct::getAnon(Fields); 2250 } 2251 2252 void CodeGenModule::AddGlobalAnnotations(const ValueDecl *D, 2253 llvm::GlobalValue *GV) { 2254 assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute"); 2255 // Get the struct elements for these annotations. 2256 for (const auto *I : D->specific_attrs<AnnotateAttr>()) 2257 Annotations.push_back(EmitAnnotateAttr(GV, I, D->getLocation())); 2258 } 2259 2260 bool CodeGenModule::isInSanitizerBlacklist(SanitizerMask Kind, 2261 llvm::Function *Fn, 2262 SourceLocation Loc) const { 2263 const auto &SanitizerBL = getContext().getSanitizerBlacklist(); 2264 // Blacklist by function name. 2265 if (SanitizerBL.isBlacklistedFunction(Kind, Fn->getName())) 2266 return true; 2267 // Blacklist by location. 2268 if (Loc.isValid()) 2269 return SanitizerBL.isBlacklistedLocation(Kind, Loc); 2270 // If location is unknown, this may be a compiler-generated function. Assume 2271 // it's located in the main file. 2272 auto &SM = Context.getSourceManager(); 2273 if (const auto *MainFile = SM.getFileEntryForID(SM.getMainFileID())) { 2274 return SanitizerBL.isBlacklistedFile(Kind, MainFile->getName()); 2275 } 2276 return false; 2277 } 2278 2279 bool CodeGenModule::isInSanitizerBlacklist(llvm::GlobalVariable *GV, 2280 SourceLocation Loc, QualType Ty, 2281 StringRef Category) const { 2282 // For now globals can be blacklisted only in ASan and KASan. 2283 const SanitizerMask EnabledAsanMask = 2284 LangOpts.Sanitize.Mask & 2285 (SanitizerKind::Address | SanitizerKind::KernelAddress | 2286 SanitizerKind::HWAddress | SanitizerKind::KernelHWAddress | 2287 SanitizerKind::MemTag); 2288 if (!EnabledAsanMask) 2289 return false; 2290 const auto &SanitizerBL = getContext().getSanitizerBlacklist(); 2291 if (SanitizerBL.isBlacklistedGlobal(EnabledAsanMask, GV->getName(), Category)) 2292 return true; 2293 if (SanitizerBL.isBlacklistedLocation(EnabledAsanMask, Loc, Category)) 2294 return true; 2295 // Check global type. 2296 if (!Ty.isNull()) { 2297 // Drill down the array types: if global variable of a fixed type is 2298 // blacklisted, we also don't instrument arrays of them. 2299 while (auto AT = dyn_cast<ArrayType>(Ty.getTypePtr())) 2300 Ty = AT->getElementType(); 2301 Ty = Ty.getCanonicalType().getUnqualifiedType(); 2302 // We allow to blacklist only record types (classes, structs etc.) 2303 if (Ty->isRecordType()) { 2304 std::string TypeStr = Ty.getAsString(getContext().getPrintingPolicy()); 2305 if (SanitizerBL.isBlacklistedType(EnabledAsanMask, TypeStr, Category)) 2306 return true; 2307 } 2308 } 2309 return false; 2310 } 2311 2312 bool CodeGenModule::imbueXRayAttrs(llvm::Function *Fn, SourceLocation Loc, 2313 StringRef Category) const { 2314 const auto &XRayFilter = getContext().getXRayFilter(); 2315 using ImbueAttr = XRayFunctionFilter::ImbueAttribute; 2316 auto Attr = ImbueAttr::NONE; 2317 if (Loc.isValid()) 2318 Attr = XRayFilter.shouldImbueLocation(Loc, Category); 2319 if (Attr == ImbueAttr::NONE) 2320 Attr = XRayFilter.shouldImbueFunction(Fn->getName()); 2321 switch (Attr) { 2322 case ImbueAttr::NONE: 2323 return false; 2324 case ImbueAttr::ALWAYS: 2325 Fn->addFnAttr("function-instrument", "xray-always"); 2326 break; 2327 case ImbueAttr::ALWAYS_ARG1: 2328 Fn->addFnAttr("function-instrument", "xray-always"); 2329 Fn->addFnAttr("xray-log-args", "1"); 2330 break; 2331 case ImbueAttr::NEVER: 2332 Fn->addFnAttr("function-instrument", "xray-never"); 2333 break; 2334 } 2335 return true; 2336 } 2337 2338 bool CodeGenModule::MustBeEmitted(const ValueDecl *Global) { 2339 // Never defer when EmitAllDecls is specified. 2340 if (LangOpts.EmitAllDecls) 2341 return true; 2342 2343 if (CodeGenOpts.KeepStaticConsts) { 2344 const auto *VD = dyn_cast<VarDecl>(Global); 2345 if (VD && VD->getType().isConstQualified() && 2346 VD->getStorageDuration() == SD_Static) 2347 return true; 2348 } 2349 2350 return getContext().DeclMustBeEmitted(Global); 2351 } 2352 2353 bool CodeGenModule::MayBeEmittedEagerly(const ValueDecl *Global) { 2354 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) { 2355 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 2356 // Implicit template instantiations may change linkage if they are later 2357 // explicitly instantiated, so they should not be emitted eagerly. 2358 return false; 2359 // In OpenMP 5.0 function may be marked as device_type(nohost) and we should 2360 // not emit them eagerly unless we sure that the function must be emitted on 2361 // the host. 2362 if (LangOpts.OpenMP >= 50 && !LangOpts.OpenMPSimd && 2363 !LangOpts.OpenMPIsDevice && 2364 !OMPDeclareTargetDeclAttr::getDeviceType(FD) && 2365 !FD->isUsed(/*CheckUsedAttr=*/false) && !FD->isReferenced()) 2366 return false; 2367 } 2368 if (const auto *VD = dyn_cast<VarDecl>(Global)) 2369 if (Context.getInlineVariableDefinitionKind(VD) == 2370 ASTContext::InlineVariableDefinitionKind::WeakUnknown) 2371 // A definition of an inline constexpr static data member may change 2372 // linkage later if it's redeclared outside the class. 2373 return false; 2374 // If OpenMP is enabled and threadprivates must be generated like TLS, delay 2375 // codegen for global variables, because they may be marked as threadprivate. 2376 if (LangOpts.OpenMP && LangOpts.OpenMPUseTLS && 2377 getContext().getTargetInfo().isTLSSupported() && isa<VarDecl>(Global) && 2378 !isTypeConstant(Global->getType(), false) && 2379 !OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(Global)) 2380 return false; 2381 2382 return true; 2383 } 2384 2385 ConstantAddress CodeGenModule::GetAddrOfUuidDescriptor( 2386 const CXXUuidofExpr* E) { 2387 // Sema has verified that IIDSource has a __declspec(uuid()), and that its 2388 // well-formed. 2389 StringRef Uuid = E->getUuidStr(); 2390 std::string Name = "_GUID_" + Uuid.lower(); 2391 std::replace(Name.begin(), Name.end(), '-', '_'); 2392 2393 // The UUID descriptor should be pointer aligned. 2394 CharUnits Alignment = CharUnits::fromQuantity(PointerAlignInBytes); 2395 2396 // Look for an existing global. 2397 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name)) 2398 return ConstantAddress(GV, Alignment); 2399 2400 llvm::Constant *Init = EmitUuidofInitializer(Uuid); 2401 assert(Init && "failed to initialize as constant"); 2402 2403 auto *GV = new llvm::GlobalVariable( 2404 getModule(), Init->getType(), 2405 /*isConstant=*/true, llvm::GlobalValue::LinkOnceODRLinkage, Init, Name); 2406 if (supportsCOMDAT()) 2407 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 2408 setDSOLocal(GV); 2409 return ConstantAddress(GV, Alignment); 2410 } 2411 2412 ConstantAddress CodeGenModule::GetWeakRefReference(const ValueDecl *VD) { 2413 const AliasAttr *AA = VD->getAttr<AliasAttr>(); 2414 assert(AA && "No alias?"); 2415 2416 CharUnits Alignment = getContext().getDeclAlign(VD); 2417 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(VD->getType()); 2418 2419 // See if there is already something with the target's name in the module. 2420 llvm::GlobalValue *Entry = GetGlobalValue(AA->getAliasee()); 2421 if (Entry) { 2422 unsigned AS = getContext().getTargetAddressSpace(VD->getType()); 2423 auto Ptr = llvm::ConstantExpr::getBitCast(Entry, DeclTy->getPointerTo(AS)); 2424 return ConstantAddress(Ptr, Alignment); 2425 } 2426 2427 llvm::Constant *Aliasee; 2428 if (isa<llvm::FunctionType>(DeclTy)) 2429 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, 2430 GlobalDecl(cast<FunctionDecl>(VD)), 2431 /*ForVTable=*/false); 2432 else 2433 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), 2434 llvm::PointerType::getUnqual(DeclTy), 2435 nullptr); 2436 2437 auto *F = cast<llvm::GlobalValue>(Aliasee); 2438 F->setLinkage(llvm::Function::ExternalWeakLinkage); 2439 WeakRefReferences.insert(F); 2440 2441 return ConstantAddress(Aliasee, Alignment); 2442 } 2443 2444 void CodeGenModule::EmitGlobal(GlobalDecl GD) { 2445 const auto *Global = cast<ValueDecl>(GD.getDecl()); 2446 2447 // Weak references don't produce any output by themselves. 2448 if (Global->hasAttr<WeakRefAttr>()) 2449 return; 2450 2451 // If this is an alias definition (which otherwise looks like a declaration) 2452 // emit it now. 2453 if (Global->hasAttr<AliasAttr>()) 2454 return EmitAliasDefinition(GD); 2455 2456 // IFunc like an alias whose value is resolved at runtime by calling resolver. 2457 if (Global->hasAttr<IFuncAttr>()) 2458 return emitIFuncDefinition(GD); 2459 2460 // If this is a cpu_dispatch multiversion function, emit the resolver. 2461 if (Global->hasAttr<CPUDispatchAttr>()) 2462 return emitCPUDispatchDefinition(GD); 2463 2464 // If this is CUDA, be selective about which declarations we emit. 2465 if (LangOpts.CUDA) { 2466 if (LangOpts.CUDAIsDevice) { 2467 if (!Global->hasAttr<CUDADeviceAttr>() && 2468 !Global->hasAttr<CUDAGlobalAttr>() && 2469 !Global->hasAttr<CUDAConstantAttr>() && 2470 !Global->hasAttr<CUDASharedAttr>() && 2471 !(LangOpts.HIP && Global->hasAttr<HIPPinnedShadowAttr>())) 2472 return; 2473 } else { 2474 // We need to emit host-side 'shadows' for all global 2475 // device-side variables because the CUDA runtime needs their 2476 // size and host-side address in order to provide access to 2477 // their device-side incarnations. 2478 2479 // So device-only functions are the only things we skip. 2480 if (isa<FunctionDecl>(Global) && !Global->hasAttr<CUDAHostAttr>() && 2481 Global->hasAttr<CUDADeviceAttr>()) 2482 return; 2483 2484 assert((isa<FunctionDecl>(Global) || isa<VarDecl>(Global)) && 2485 "Expected Variable or Function"); 2486 } 2487 } 2488 2489 if (LangOpts.OpenMP) { 2490 // If this is OpenMP, check if it is legal to emit this global normally. 2491 if (OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(GD)) 2492 return; 2493 if (auto *DRD = dyn_cast<OMPDeclareReductionDecl>(Global)) { 2494 if (MustBeEmitted(Global)) 2495 EmitOMPDeclareReduction(DRD); 2496 return; 2497 } else if (auto *DMD = dyn_cast<OMPDeclareMapperDecl>(Global)) { 2498 if (MustBeEmitted(Global)) 2499 EmitOMPDeclareMapper(DMD); 2500 return; 2501 } 2502 } 2503 2504 // Ignore declarations, they will be emitted on their first use. 2505 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) { 2506 // Forward declarations are emitted lazily on first use. 2507 if (!FD->doesThisDeclarationHaveABody()) { 2508 if (!FD->doesDeclarationForceExternallyVisibleDefinition()) 2509 return; 2510 2511 StringRef MangledName = getMangledName(GD); 2512 2513 // Compute the function info and LLVM type. 2514 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 2515 llvm::Type *Ty = getTypes().GetFunctionType(FI); 2516 2517 GetOrCreateLLVMFunction(MangledName, Ty, GD, /*ForVTable=*/false, 2518 /*DontDefer=*/false); 2519 return; 2520 } 2521 } else { 2522 const auto *VD = cast<VarDecl>(Global); 2523 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global."); 2524 if (VD->isThisDeclarationADefinition() != VarDecl::Definition && 2525 !Context.isMSStaticDataMemberInlineDefinition(VD)) { 2526 if (LangOpts.OpenMP) { 2527 // Emit declaration of the must-be-emitted declare target variable. 2528 if (llvm::Optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res = 2529 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD)) { 2530 bool UnifiedMemoryEnabled = 2531 getOpenMPRuntime().hasRequiresUnifiedSharedMemory(); 2532 if (*Res == OMPDeclareTargetDeclAttr::MT_To && 2533 !UnifiedMemoryEnabled) { 2534 (void)GetAddrOfGlobalVar(VD); 2535 } else { 2536 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) || 2537 (*Res == OMPDeclareTargetDeclAttr::MT_To && 2538 UnifiedMemoryEnabled)) && 2539 "Link clause or to clause with unified memory expected."); 2540 (void)getOpenMPRuntime().getAddrOfDeclareTargetVar(VD); 2541 } 2542 2543 return; 2544 } 2545 } 2546 // If this declaration may have caused an inline variable definition to 2547 // change linkage, make sure that it's emitted. 2548 if (Context.getInlineVariableDefinitionKind(VD) == 2549 ASTContext::InlineVariableDefinitionKind::Strong) 2550 GetAddrOfGlobalVar(VD); 2551 return; 2552 } 2553 } 2554 2555 // Defer code generation to first use when possible, e.g. if this is an inline 2556 // function. If the global must always be emitted, do it eagerly if possible 2557 // to benefit from cache locality. 2558 if (MustBeEmitted(Global) && MayBeEmittedEagerly(Global)) { 2559 // Emit the definition if it can't be deferred. 2560 EmitGlobalDefinition(GD); 2561 return; 2562 } 2563 2564 // Check if this must be emitted as declare variant. 2565 if (LangOpts.OpenMP && isa<FunctionDecl>(Global) && OpenMPRuntime && 2566 OpenMPRuntime->emitDeclareVariant(GD, /*IsForDefinition=*/false)) 2567 return; 2568 2569 // If we're deferring emission of a C++ variable with an 2570 // initializer, remember the order in which it appeared in the file. 2571 if (getLangOpts().CPlusPlus && isa<VarDecl>(Global) && 2572 cast<VarDecl>(Global)->hasInit()) { 2573 DelayedCXXInitPosition[Global] = CXXGlobalInits.size(); 2574 CXXGlobalInits.push_back(nullptr); 2575 } 2576 2577 StringRef MangledName = getMangledName(GD); 2578 if (GetGlobalValue(MangledName) != nullptr) { 2579 // The value has already been used and should therefore be emitted. 2580 addDeferredDeclToEmit(GD); 2581 } else if (MustBeEmitted(Global)) { 2582 // The value must be emitted, but cannot be emitted eagerly. 2583 assert(!MayBeEmittedEagerly(Global)); 2584 addDeferredDeclToEmit(GD); 2585 } else { 2586 // Otherwise, remember that we saw a deferred decl with this name. The 2587 // first use of the mangled name will cause it to move into 2588 // DeferredDeclsToEmit. 2589 DeferredDecls[MangledName] = GD; 2590 } 2591 } 2592 2593 // Check if T is a class type with a destructor that's not dllimport. 2594 static bool HasNonDllImportDtor(QualType T) { 2595 if (const auto *RT = T->getBaseElementTypeUnsafe()->getAs<RecordType>()) 2596 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) 2597 if (RD->getDestructor() && !RD->getDestructor()->hasAttr<DLLImportAttr>()) 2598 return true; 2599 2600 return false; 2601 } 2602 2603 namespace { 2604 struct FunctionIsDirectlyRecursive 2605 : public ConstStmtVisitor<FunctionIsDirectlyRecursive, bool> { 2606 const StringRef Name; 2607 const Builtin::Context &BI; 2608 FunctionIsDirectlyRecursive(StringRef N, const Builtin::Context &C) 2609 : Name(N), BI(C) {} 2610 2611 bool VisitCallExpr(const CallExpr *E) { 2612 const FunctionDecl *FD = E->getDirectCallee(); 2613 if (!FD) 2614 return false; 2615 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>(); 2616 if (Attr && Name == Attr->getLabel()) 2617 return true; 2618 unsigned BuiltinID = FD->getBuiltinID(); 2619 if (!BuiltinID || !BI.isLibFunction(BuiltinID)) 2620 return false; 2621 StringRef BuiltinName = BI.getName(BuiltinID); 2622 if (BuiltinName.startswith("__builtin_") && 2623 Name == BuiltinName.slice(strlen("__builtin_"), StringRef::npos)) { 2624 return true; 2625 } 2626 return false; 2627 } 2628 2629 bool VisitStmt(const Stmt *S) { 2630 for (const Stmt *Child : S->children()) 2631 if (Child && this->Visit(Child)) 2632 return true; 2633 return false; 2634 } 2635 }; 2636 2637 // Make sure we're not referencing non-imported vars or functions. 2638 struct DLLImportFunctionVisitor 2639 : public RecursiveASTVisitor<DLLImportFunctionVisitor> { 2640 bool SafeToInline = true; 2641 2642 bool shouldVisitImplicitCode() const { return true; } 2643 2644 bool VisitVarDecl(VarDecl *VD) { 2645 if (VD->getTLSKind()) { 2646 // A thread-local variable cannot be imported. 2647 SafeToInline = false; 2648 return SafeToInline; 2649 } 2650 2651 // A variable definition might imply a destructor call. 2652 if (VD->isThisDeclarationADefinition()) 2653 SafeToInline = !HasNonDllImportDtor(VD->getType()); 2654 2655 return SafeToInline; 2656 } 2657 2658 bool VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { 2659 if (const auto *D = E->getTemporary()->getDestructor()) 2660 SafeToInline = D->hasAttr<DLLImportAttr>(); 2661 return SafeToInline; 2662 } 2663 2664 bool VisitDeclRefExpr(DeclRefExpr *E) { 2665 ValueDecl *VD = E->getDecl(); 2666 if (isa<FunctionDecl>(VD)) 2667 SafeToInline = VD->hasAttr<DLLImportAttr>(); 2668 else if (VarDecl *V = dyn_cast<VarDecl>(VD)) 2669 SafeToInline = !V->hasGlobalStorage() || V->hasAttr<DLLImportAttr>(); 2670 return SafeToInline; 2671 } 2672 2673 bool VisitCXXConstructExpr(CXXConstructExpr *E) { 2674 SafeToInline = E->getConstructor()->hasAttr<DLLImportAttr>(); 2675 return SafeToInline; 2676 } 2677 2678 bool VisitCXXMemberCallExpr(CXXMemberCallExpr *E) { 2679 CXXMethodDecl *M = E->getMethodDecl(); 2680 if (!M) { 2681 // Call through a pointer to member function. This is safe to inline. 2682 SafeToInline = true; 2683 } else { 2684 SafeToInline = M->hasAttr<DLLImportAttr>(); 2685 } 2686 return SafeToInline; 2687 } 2688 2689 bool VisitCXXDeleteExpr(CXXDeleteExpr *E) { 2690 SafeToInline = E->getOperatorDelete()->hasAttr<DLLImportAttr>(); 2691 return SafeToInline; 2692 } 2693 2694 bool VisitCXXNewExpr(CXXNewExpr *E) { 2695 SafeToInline = E->getOperatorNew()->hasAttr<DLLImportAttr>(); 2696 return SafeToInline; 2697 } 2698 }; 2699 } 2700 2701 // isTriviallyRecursive - Check if this function calls another 2702 // decl that, because of the asm attribute or the other decl being a builtin, 2703 // ends up pointing to itself. 2704 bool 2705 CodeGenModule::isTriviallyRecursive(const FunctionDecl *FD) { 2706 StringRef Name; 2707 if (getCXXABI().getMangleContext().shouldMangleDeclName(FD)) { 2708 // asm labels are a special kind of mangling we have to support. 2709 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>(); 2710 if (!Attr) 2711 return false; 2712 Name = Attr->getLabel(); 2713 } else { 2714 Name = FD->getName(); 2715 } 2716 2717 FunctionIsDirectlyRecursive Walker(Name, Context.BuiltinInfo); 2718 const Stmt *Body = FD->getBody(); 2719 return Body ? Walker.Visit(Body) : false; 2720 } 2721 2722 bool CodeGenModule::shouldEmitFunction(GlobalDecl GD) { 2723 if (getFunctionLinkage(GD) != llvm::Function::AvailableExternallyLinkage) 2724 return true; 2725 const auto *F = cast<FunctionDecl>(GD.getDecl()); 2726 if (CodeGenOpts.OptimizationLevel == 0 && !F->hasAttr<AlwaysInlineAttr>()) 2727 return false; 2728 2729 if (F->hasAttr<DLLImportAttr>()) { 2730 // Check whether it would be safe to inline this dllimport function. 2731 DLLImportFunctionVisitor Visitor; 2732 Visitor.TraverseFunctionDecl(const_cast<FunctionDecl*>(F)); 2733 if (!Visitor.SafeToInline) 2734 return false; 2735 2736 if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(F)) { 2737 // Implicit destructor invocations aren't captured in the AST, so the 2738 // check above can't see them. Check for them manually here. 2739 for (const Decl *Member : Dtor->getParent()->decls()) 2740 if (isa<FieldDecl>(Member)) 2741 if (HasNonDllImportDtor(cast<FieldDecl>(Member)->getType())) 2742 return false; 2743 for (const CXXBaseSpecifier &B : Dtor->getParent()->bases()) 2744 if (HasNonDllImportDtor(B.getType())) 2745 return false; 2746 } 2747 } 2748 2749 // PR9614. Avoid cases where the source code is lying to us. An available 2750 // externally function should have an equivalent function somewhere else, 2751 // but a function that calls itself is clearly not equivalent to the real 2752 // implementation. 2753 // This happens in glibc's btowc and in some configure checks. 2754 return !isTriviallyRecursive(F); 2755 } 2756 2757 bool CodeGenModule::shouldOpportunisticallyEmitVTables() { 2758 return CodeGenOpts.OptimizationLevel > 0; 2759 } 2760 2761 void CodeGenModule::EmitMultiVersionFunctionDefinition(GlobalDecl GD, 2762 llvm::GlobalValue *GV) { 2763 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 2764 2765 if (FD->isCPUSpecificMultiVersion()) { 2766 auto *Spec = FD->getAttr<CPUSpecificAttr>(); 2767 for (unsigned I = 0; I < Spec->cpus_size(); ++I) 2768 EmitGlobalFunctionDefinition(GD.getWithMultiVersionIndex(I), nullptr); 2769 // Requires multiple emits. 2770 } else 2771 EmitGlobalFunctionDefinition(GD, GV); 2772 } 2773 2774 void CodeGenModule::emitOpenMPDeviceFunctionRedefinition( 2775 GlobalDecl OldGD, GlobalDecl NewGD, llvm::GlobalValue *GV) { 2776 assert(getLangOpts().OpenMP && getLangOpts().OpenMPIsDevice && 2777 OpenMPRuntime && "Expected OpenMP device mode."); 2778 const auto *D = cast<FunctionDecl>(OldGD.getDecl()); 2779 2780 // Compute the function info and LLVM type. 2781 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(OldGD); 2782 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 2783 2784 // Get or create the prototype for the function. 2785 if (!GV || (GV->getType()->getElementType() != Ty)) { 2786 GV = cast<llvm::GlobalValue>(GetOrCreateLLVMFunction( 2787 getMangledName(OldGD), Ty, GlobalDecl(), /*ForVTable=*/false, 2788 /*DontDefer=*/true, /*IsThunk=*/false, llvm::AttributeList(), 2789 ForDefinition)); 2790 SetFunctionAttributes(OldGD, cast<llvm::Function>(GV), 2791 /*IsIncompleteFunction=*/false, 2792 /*IsThunk=*/false); 2793 } 2794 // We need to set linkage and visibility on the function before 2795 // generating code for it because various parts of IR generation 2796 // want to propagate this information down (e.g. to local static 2797 // declarations). 2798 auto *Fn = cast<llvm::Function>(GV); 2799 setFunctionLinkage(OldGD, Fn); 2800 2801 // FIXME: this is redundant with part of 2802 // setFunctionDefinitionAttributes 2803 setGVProperties(Fn, OldGD); 2804 2805 MaybeHandleStaticInExternC(D, Fn); 2806 2807 maybeSetTrivialComdat(*D, *Fn); 2808 2809 CodeGenFunction(*this).GenerateCode(NewGD, Fn, FI); 2810 2811 setNonAliasAttributes(OldGD, Fn); 2812 SetLLVMFunctionAttributesForDefinition(D, Fn); 2813 2814 if (D->hasAttr<AnnotateAttr>()) 2815 AddGlobalAnnotations(D, Fn); 2816 } 2817 2818 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD, llvm::GlobalValue *GV) { 2819 const auto *D = cast<ValueDecl>(GD.getDecl()); 2820 2821 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(), 2822 Context.getSourceManager(), 2823 "Generating code for declaration"); 2824 2825 if (const auto *FD = dyn_cast<FunctionDecl>(D)) { 2826 // At -O0, don't generate IR for functions with available_externally 2827 // linkage. 2828 if (!shouldEmitFunction(GD)) 2829 return; 2830 2831 llvm::TimeTraceScope TimeScope("CodeGen Function", [&]() { 2832 std::string Name; 2833 llvm::raw_string_ostream OS(Name); 2834 FD->getNameForDiagnostic(OS, getContext().getPrintingPolicy(), 2835 /*Qualified=*/true); 2836 return Name; 2837 }); 2838 2839 if (const auto *Method = dyn_cast<CXXMethodDecl>(D)) { 2840 // Make sure to emit the definition(s) before we emit the thunks. 2841 // This is necessary for the generation of certain thunks. 2842 if (isa<CXXConstructorDecl>(Method) || isa<CXXDestructorDecl>(Method)) 2843 ABI->emitCXXStructor(GD); 2844 else if (FD->isMultiVersion()) 2845 EmitMultiVersionFunctionDefinition(GD, GV); 2846 else 2847 EmitGlobalFunctionDefinition(GD, GV); 2848 2849 if (Method->isVirtual()) 2850 getVTables().EmitThunks(GD); 2851 2852 return; 2853 } 2854 2855 if (FD->isMultiVersion()) 2856 return EmitMultiVersionFunctionDefinition(GD, GV); 2857 return EmitGlobalFunctionDefinition(GD, GV); 2858 } 2859 2860 if (const auto *VD = dyn_cast<VarDecl>(D)) 2861 return EmitGlobalVarDefinition(VD, !VD->hasDefinition()); 2862 2863 llvm_unreachable("Invalid argument to EmitGlobalDefinition()"); 2864 } 2865 2866 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 2867 llvm::Function *NewFn); 2868 2869 static unsigned 2870 TargetMVPriority(const TargetInfo &TI, 2871 const CodeGenFunction::MultiVersionResolverOption &RO) { 2872 unsigned Priority = 0; 2873 for (StringRef Feat : RO.Conditions.Features) 2874 Priority = std::max(Priority, TI.multiVersionSortPriority(Feat)); 2875 2876 if (!RO.Conditions.Architecture.empty()) 2877 Priority = std::max( 2878 Priority, TI.multiVersionSortPriority(RO.Conditions.Architecture)); 2879 return Priority; 2880 } 2881 2882 void CodeGenModule::emitMultiVersionFunctions() { 2883 for (GlobalDecl GD : MultiVersionFuncs) { 2884 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options; 2885 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 2886 getContext().forEachMultiversionedFunctionVersion( 2887 FD, [this, &GD, &Options](const FunctionDecl *CurFD) { 2888 GlobalDecl CurGD{ 2889 (CurFD->isDefined() ? CurFD->getDefinition() : CurFD)}; 2890 StringRef MangledName = getMangledName(CurGD); 2891 llvm::Constant *Func = GetGlobalValue(MangledName); 2892 if (!Func) { 2893 if (CurFD->isDefined()) { 2894 EmitGlobalFunctionDefinition(CurGD, nullptr); 2895 Func = GetGlobalValue(MangledName); 2896 } else { 2897 const CGFunctionInfo &FI = 2898 getTypes().arrangeGlobalDeclaration(GD); 2899 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 2900 Func = GetAddrOfFunction(CurGD, Ty, /*ForVTable=*/false, 2901 /*DontDefer=*/false, ForDefinition); 2902 } 2903 assert(Func && "This should have just been created"); 2904 } 2905 2906 const auto *TA = CurFD->getAttr<TargetAttr>(); 2907 llvm::SmallVector<StringRef, 8> Feats; 2908 TA->getAddedFeatures(Feats); 2909 2910 Options.emplace_back(cast<llvm::Function>(Func), 2911 TA->getArchitecture(), Feats); 2912 }); 2913 2914 llvm::Function *ResolverFunc; 2915 const TargetInfo &TI = getTarget(); 2916 2917 if (TI.supportsIFunc() || FD->isTargetMultiVersion()) { 2918 ResolverFunc = cast<llvm::Function>( 2919 GetGlobalValue((getMangledName(GD) + ".resolver").str())); 2920 ResolverFunc->setLinkage(llvm::Function::WeakODRLinkage); 2921 } else { 2922 ResolverFunc = cast<llvm::Function>(GetGlobalValue(getMangledName(GD))); 2923 } 2924 2925 if (supportsCOMDAT()) 2926 ResolverFunc->setComdat( 2927 getModule().getOrInsertComdat(ResolverFunc->getName())); 2928 2929 llvm::stable_sort( 2930 Options, [&TI](const CodeGenFunction::MultiVersionResolverOption &LHS, 2931 const CodeGenFunction::MultiVersionResolverOption &RHS) { 2932 return TargetMVPriority(TI, LHS) > TargetMVPriority(TI, RHS); 2933 }); 2934 CodeGenFunction CGF(*this); 2935 CGF.EmitMultiVersionResolver(ResolverFunc, Options); 2936 } 2937 } 2938 2939 void CodeGenModule::emitCPUDispatchDefinition(GlobalDecl GD) { 2940 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 2941 assert(FD && "Not a FunctionDecl?"); 2942 const auto *DD = FD->getAttr<CPUDispatchAttr>(); 2943 assert(DD && "Not a cpu_dispatch Function?"); 2944 llvm::Type *DeclTy = getTypes().ConvertType(FD->getType()); 2945 2946 if (const auto *CXXFD = dyn_cast<CXXMethodDecl>(FD)) { 2947 const CGFunctionInfo &FInfo = getTypes().arrangeCXXMethodDeclaration(CXXFD); 2948 DeclTy = getTypes().GetFunctionType(FInfo); 2949 } 2950 2951 StringRef ResolverName = getMangledName(GD); 2952 2953 llvm::Type *ResolverType; 2954 GlobalDecl ResolverGD; 2955 if (getTarget().supportsIFunc()) 2956 ResolverType = llvm::FunctionType::get( 2957 llvm::PointerType::get(DeclTy, 2958 Context.getTargetAddressSpace(FD->getType())), 2959 false); 2960 else { 2961 ResolverType = DeclTy; 2962 ResolverGD = GD; 2963 } 2964 2965 auto *ResolverFunc = cast<llvm::Function>(GetOrCreateLLVMFunction( 2966 ResolverName, ResolverType, ResolverGD, /*ForVTable=*/false)); 2967 ResolverFunc->setLinkage(llvm::Function::WeakODRLinkage); 2968 if (supportsCOMDAT()) 2969 ResolverFunc->setComdat( 2970 getModule().getOrInsertComdat(ResolverFunc->getName())); 2971 2972 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options; 2973 const TargetInfo &Target = getTarget(); 2974 unsigned Index = 0; 2975 for (const IdentifierInfo *II : DD->cpus()) { 2976 // Get the name of the target function so we can look it up/create it. 2977 std::string MangledName = getMangledNameImpl(*this, GD, FD, true) + 2978 getCPUSpecificMangling(*this, II->getName()); 2979 2980 llvm::Constant *Func = GetGlobalValue(MangledName); 2981 2982 if (!Func) { 2983 GlobalDecl ExistingDecl = Manglings.lookup(MangledName); 2984 if (ExistingDecl.getDecl() && 2985 ExistingDecl.getDecl()->getAsFunction()->isDefined()) { 2986 EmitGlobalFunctionDefinition(ExistingDecl, nullptr); 2987 Func = GetGlobalValue(MangledName); 2988 } else { 2989 if (!ExistingDecl.getDecl()) 2990 ExistingDecl = GD.getWithMultiVersionIndex(Index); 2991 2992 Func = GetOrCreateLLVMFunction( 2993 MangledName, DeclTy, ExistingDecl, 2994 /*ForVTable=*/false, /*DontDefer=*/true, 2995 /*IsThunk=*/false, llvm::AttributeList(), ForDefinition); 2996 } 2997 } 2998 2999 llvm::SmallVector<StringRef, 32> Features; 3000 Target.getCPUSpecificCPUDispatchFeatures(II->getName(), Features); 3001 llvm::transform(Features, Features.begin(), 3002 [](StringRef Str) { return Str.substr(1); }); 3003 Features.erase(std::remove_if( 3004 Features.begin(), Features.end(), [&Target](StringRef Feat) { 3005 return !Target.validateCpuSupports(Feat); 3006 }), Features.end()); 3007 Options.emplace_back(cast<llvm::Function>(Func), StringRef{}, Features); 3008 ++Index; 3009 } 3010 3011 llvm::sort( 3012 Options, [](const CodeGenFunction::MultiVersionResolverOption &LHS, 3013 const CodeGenFunction::MultiVersionResolverOption &RHS) { 3014 return CodeGenFunction::GetX86CpuSupportsMask(LHS.Conditions.Features) > 3015 CodeGenFunction::GetX86CpuSupportsMask(RHS.Conditions.Features); 3016 }); 3017 3018 // If the list contains multiple 'default' versions, such as when it contains 3019 // 'pentium' and 'generic', don't emit the call to the generic one (since we 3020 // always run on at least a 'pentium'). We do this by deleting the 'least 3021 // advanced' (read, lowest mangling letter). 3022 while (Options.size() > 1 && 3023 CodeGenFunction::GetX86CpuSupportsMask( 3024 (Options.end() - 2)->Conditions.Features) == 0) { 3025 StringRef LHSName = (Options.end() - 2)->Function->getName(); 3026 StringRef RHSName = (Options.end() - 1)->Function->getName(); 3027 if (LHSName.compare(RHSName) < 0) 3028 Options.erase(Options.end() - 2); 3029 else 3030 Options.erase(Options.end() - 1); 3031 } 3032 3033 CodeGenFunction CGF(*this); 3034 CGF.EmitMultiVersionResolver(ResolverFunc, Options); 3035 3036 if (getTarget().supportsIFunc()) { 3037 std::string AliasName = getMangledNameImpl( 3038 *this, GD, FD, /*OmitMultiVersionMangling=*/true); 3039 llvm::Constant *AliasFunc = GetGlobalValue(AliasName); 3040 if (!AliasFunc) { 3041 auto *IFunc = cast<llvm::GlobalIFunc>(GetOrCreateLLVMFunction( 3042 AliasName, DeclTy, GD, /*ForVTable=*/false, /*DontDefer=*/true, 3043 /*IsThunk=*/false, llvm::AttributeList(), NotForDefinition)); 3044 auto *GA = llvm::GlobalAlias::create( 3045 DeclTy, 0, getFunctionLinkage(GD), AliasName, IFunc, &getModule()); 3046 GA->setLinkage(llvm::Function::WeakODRLinkage); 3047 SetCommonAttributes(GD, GA); 3048 } 3049 } 3050 } 3051 3052 /// If a dispatcher for the specified mangled name is not in the module, create 3053 /// and return an llvm Function with the specified type. 3054 llvm::Constant *CodeGenModule::GetOrCreateMultiVersionResolver( 3055 GlobalDecl GD, llvm::Type *DeclTy, const FunctionDecl *FD) { 3056 std::string MangledName = 3057 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true); 3058 3059 // Holds the name of the resolver, in ifunc mode this is the ifunc (which has 3060 // a separate resolver). 3061 std::string ResolverName = MangledName; 3062 if (getTarget().supportsIFunc()) 3063 ResolverName += ".ifunc"; 3064 else if (FD->isTargetMultiVersion()) 3065 ResolverName += ".resolver"; 3066 3067 // If this already exists, just return that one. 3068 if (llvm::GlobalValue *ResolverGV = GetGlobalValue(ResolverName)) 3069 return ResolverGV; 3070 3071 // Since this is the first time we've created this IFunc, make sure 3072 // that we put this multiversioned function into the list to be 3073 // replaced later if necessary (target multiversioning only). 3074 if (!FD->isCPUDispatchMultiVersion() && !FD->isCPUSpecificMultiVersion()) 3075 MultiVersionFuncs.push_back(GD); 3076 3077 if (getTarget().supportsIFunc()) { 3078 llvm::Type *ResolverType = llvm::FunctionType::get( 3079 llvm::PointerType::get( 3080 DeclTy, getContext().getTargetAddressSpace(FD->getType())), 3081 false); 3082 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 3083 MangledName + ".resolver", ResolverType, GlobalDecl{}, 3084 /*ForVTable=*/false); 3085 llvm::GlobalIFunc *GIF = llvm::GlobalIFunc::create( 3086 DeclTy, 0, llvm::Function::WeakODRLinkage, "", Resolver, &getModule()); 3087 GIF->setName(ResolverName); 3088 SetCommonAttributes(FD, GIF); 3089 3090 return GIF; 3091 } 3092 3093 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 3094 ResolverName, DeclTy, GlobalDecl{}, /*ForVTable=*/false); 3095 assert(isa<llvm::GlobalValue>(Resolver) && 3096 "Resolver should be created for the first time"); 3097 SetCommonAttributes(FD, cast<llvm::GlobalValue>(Resolver)); 3098 return Resolver; 3099 } 3100 3101 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the 3102 /// module, create and return an llvm Function with the specified type. If there 3103 /// is something in the module with the specified name, return it potentially 3104 /// bitcasted to the right type. 3105 /// 3106 /// If D is non-null, it specifies a decl that correspond to this. This is used 3107 /// to set the attributes on the function when it is first created. 3108 llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction( 3109 StringRef MangledName, llvm::Type *Ty, GlobalDecl GD, bool ForVTable, 3110 bool DontDefer, bool IsThunk, llvm::AttributeList ExtraAttrs, 3111 ForDefinition_t IsForDefinition) { 3112 const Decl *D = GD.getDecl(); 3113 3114 // Any attempts to use a MultiVersion function should result in retrieving 3115 // the iFunc instead. Name Mangling will handle the rest of the changes. 3116 if (const FunctionDecl *FD = cast_or_null<FunctionDecl>(D)) { 3117 // For the device mark the function as one that should be emitted. 3118 if (getLangOpts().OpenMPIsDevice && OpenMPRuntime && 3119 !OpenMPRuntime->markAsGlobalTarget(GD) && FD->isDefined() && 3120 !DontDefer && !IsForDefinition) { 3121 if (const FunctionDecl *FDDef = FD->getDefinition()) { 3122 GlobalDecl GDDef; 3123 if (const auto *CD = dyn_cast<CXXConstructorDecl>(FDDef)) 3124 GDDef = GlobalDecl(CD, GD.getCtorType()); 3125 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(FDDef)) 3126 GDDef = GlobalDecl(DD, GD.getDtorType()); 3127 else 3128 GDDef = GlobalDecl(FDDef); 3129 EmitGlobal(GDDef); 3130 } 3131 } 3132 // Check if this must be emitted as declare variant and emit reference to 3133 // the the declare variant function. 3134 if (LangOpts.OpenMP && OpenMPRuntime) 3135 (void)OpenMPRuntime->emitDeclareVariant(GD, /*IsForDefinition=*/true); 3136 3137 if (FD->isMultiVersion()) { 3138 const auto *TA = FD->getAttr<TargetAttr>(); 3139 if (TA && TA->isDefaultVersion()) 3140 UpdateMultiVersionNames(GD, FD); 3141 if (!IsForDefinition) 3142 return GetOrCreateMultiVersionResolver(GD, Ty, FD); 3143 } 3144 } 3145 3146 // Lookup the entry, lazily creating it if necessary. 3147 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 3148 if (Entry) { 3149 if (WeakRefReferences.erase(Entry)) { 3150 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D); 3151 if (FD && !FD->hasAttr<WeakAttr>()) 3152 Entry->setLinkage(llvm::Function::ExternalLinkage); 3153 } 3154 3155 // Handle dropped DLL attributes. 3156 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>()) { 3157 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass); 3158 setDSOLocal(Entry); 3159 } 3160 3161 // If there are two attempts to define the same mangled name, issue an 3162 // error. 3163 if (IsForDefinition && !Entry->isDeclaration()) { 3164 GlobalDecl OtherGD; 3165 // Check that GD is not yet in DiagnosedConflictingDefinitions is required 3166 // to make sure that we issue an error only once. 3167 if (lookupRepresentativeDecl(MangledName, OtherGD) && 3168 (GD.getCanonicalDecl().getDecl() != 3169 OtherGD.getCanonicalDecl().getDecl()) && 3170 DiagnosedConflictingDefinitions.insert(GD).second) { 3171 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name) 3172 << MangledName; 3173 getDiags().Report(OtherGD.getDecl()->getLocation(), 3174 diag::note_previous_definition); 3175 } 3176 } 3177 3178 if ((isa<llvm::Function>(Entry) || isa<llvm::GlobalAlias>(Entry)) && 3179 (Entry->getType()->getElementType() == Ty)) { 3180 return Entry; 3181 } 3182 3183 // Make sure the result is of the correct type. 3184 // (If function is requested for a definition, we always need to create a new 3185 // function, not just return a bitcast.) 3186 if (!IsForDefinition) 3187 return llvm::ConstantExpr::getBitCast(Entry, Ty->getPointerTo()); 3188 } 3189 3190 // This function doesn't have a complete type (for example, the return 3191 // type is an incomplete struct). Use a fake type instead, and make 3192 // sure not to try to set attributes. 3193 bool IsIncompleteFunction = false; 3194 3195 llvm::FunctionType *FTy; 3196 if (isa<llvm::FunctionType>(Ty)) { 3197 FTy = cast<llvm::FunctionType>(Ty); 3198 } else { 3199 FTy = llvm::FunctionType::get(VoidTy, false); 3200 IsIncompleteFunction = true; 3201 } 3202 3203 llvm::Function *F = 3204 llvm::Function::Create(FTy, llvm::Function::ExternalLinkage, 3205 Entry ? StringRef() : MangledName, &getModule()); 3206 3207 // If we already created a function with the same mangled name (but different 3208 // type) before, take its name and add it to the list of functions to be 3209 // replaced with F at the end of CodeGen. 3210 // 3211 // This happens if there is a prototype for a function (e.g. "int f()") and 3212 // then a definition of a different type (e.g. "int f(int x)"). 3213 if (Entry) { 3214 F->takeName(Entry); 3215 3216 // This might be an implementation of a function without a prototype, in 3217 // which case, try to do special replacement of calls which match the new 3218 // prototype. The really key thing here is that we also potentially drop 3219 // arguments from the call site so as to make a direct call, which makes the 3220 // inliner happier and suppresses a number of optimizer warnings (!) about 3221 // dropping arguments. 3222 if (!Entry->use_empty()) { 3223 ReplaceUsesOfNonProtoTypeWithRealFunction(Entry, F); 3224 Entry->removeDeadConstantUsers(); 3225 } 3226 3227 llvm::Constant *BC = llvm::ConstantExpr::getBitCast( 3228 F, Entry->getType()->getElementType()->getPointerTo()); 3229 addGlobalValReplacement(Entry, BC); 3230 } 3231 3232 assert(F->getName() == MangledName && "name was uniqued!"); 3233 if (D) 3234 SetFunctionAttributes(GD, F, IsIncompleteFunction, IsThunk); 3235 if (ExtraAttrs.hasAttributes(llvm::AttributeList::FunctionIndex)) { 3236 llvm::AttrBuilder B(ExtraAttrs, llvm::AttributeList::FunctionIndex); 3237 F->addAttributes(llvm::AttributeList::FunctionIndex, B); 3238 } 3239 3240 if (!DontDefer) { 3241 // All MSVC dtors other than the base dtor are linkonce_odr and delegate to 3242 // each other bottoming out with the base dtor. Therefore we emit non-base 3243 // dtors on usage, even if there is no dtor definition in the TU. 3244 if (D && isa<CXXDestructorDecl>(D) && 3245 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D), 3246 GD.getDtorType())) 3247 addDeferredDeclToEmit(GD); 3248 3249 // This is the first use or definition of a mangled name. If there is a 3250 // deferred decl with this name, remember that we need to emit it at the end 3251 // of the file. 3252 auto DDI = DeferredDecls.find(MangledName); 3253 if (DDI != DeferredDecls.end()) { 3254 // Move the potentially referenced deferred decl to the 3255 // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we 3256 // don't need it anymore). 3257 addDeferredDeclToEmit(DDI->second); 3258 DeferredDecls.erase(DDI); 3259 3260 // Otherwise, there are cases we have to worry about where we're 3261 // using a declaration for which we must emit a definition but where 3262 // we might not find a top-level definition: 3263 // - member functions defined inline in their classes 3264 // - friend functions defined inline in some class 3265 // - special member functions with implicit definitions 3266 // If we ever change our AST traversal to walk into class methods, 3267 // this will be unnecessary. 3268 // 3269 // We also don't emit a definition for a function if it's going to be an 3270 // entry in a vtable, unless it's already marked as used. 3271 } else if (getLangOpts().CPlusPlus && D) { 3272 // Look for a declaration that's lexically in a record. 3273 for (const auto *FD = cast<FunctionDecl>(D)->getMostRecentDecl(); FD; 3274 FD = FD->getPreviousDecl()) { 3275 if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) { 3276 if (FD->doesThisDeclarationHaveABody()) { 3277 addDeferredDeclToEmit(GD.getWithDecl(FD)); 3278 break; 3279 } 3280 } 3281 } 3282 } 3283 } 3284 3285 // Make sure the result is of the requested type. 3286 if (!IsIncompleteFunction) { 3287 assert(F->getType()->getElementType() == Ty); 3288 return F; 3289 } 3290 3291 llvm::Type *PTy = llvm::PointerType::getUnqual(Ty); 3292 return llvm::ConstantExpr::getBitCast(F, PTy); 3293 } 3294 3295 /// GetAddrOfFunction - Return the address of the given function. If Ty is 3296 /// non-null, then this function will use the specified type if it has to 3297 /// create it (this occurs when we see a definition of the function). 3298 llvm::Constant *CodeGenModule::GetAddrOfFunction(GlobalDecl GD, 3299 llvm::Type *Ty, 3300 bool ForVTable, 3301 bool DontDefer, 3302 ForDefinition_t IsForDefinition) { 3303 // If there was no specific requested type, just convert it now. 3304 if (!Ty) { 3305 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 3306 Ty = getTypes().ConvertType(FD->getType()); 3307 } 3308 3309 // Devirtualized destructor calls may come through here instead of via 3310 // getAddrOfCXXStructor. Make sure we use the MS ABI base destructor instead 3311 // of the complete destructor when necessary. 3312 if (const auto *DD = dyn_cast<CXXDestructorDecl>(GD.getDecl())) { 3313 if (getTarget().getCXXABI().isMicrosoft() && 3314 GD.getDtorType() == Dtor_Complete && 3315 DD->getParent()->getNumVBases() == 0) 3316 GD = GlobalDecl(DD, Dtor_Base); 3317 } 3318 3319 StringRef MangledName = getMangledName(GD); 3320 return GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable, DontDefer, 3321 /*IsThunk=*/false, llvm::AttributeList(), 3322 IsForDefinition); 3323 } 3324 3325 static const FunctionDecl * 3326 GetRuntimeFunctionDecl(ASTContext &C, StringRef Name) { 3327 TranslationUnitDecl *TUDecl = C.getTranslationUnitDecl(); 3328 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); 3329 3330 IdentifierInfo &CII = C.Idents.get(Name); 3331 for (const auto &Result : DC->lookup(&CII)) 3332 if (const auto FD = dyn_cast<FunctionDecl>(Result)) 3333 return FD; 3334 3335 if (!C.getLangOpts().CPlusPlus) 3336 return nullptr; 3337 3338 // Demangle the premangled name from getTerminateFn() 3339 IdentifierInfo &CXXII = 3340 (Name == "_ZSt9terminatev" || Name == "?terminate@@YAXXZ") 3341 ? C.Idents.get("terminate") 3342 : C.Idents.get(Name); 3343 3344 for (const auto &N : {"__cxxabiv1", "std"}) { 3345 IdentifierInfo &NS = C.Idents.get(N); 3346 for (const auto &Result : DC->lookup(&NS)) { 3347 NamespaceDecl *ND = dyn_cast<NamespaceDecl>(Result); 3348 if (auto LSD = dyn_cast<LinkageSpecDecl>(Result)) 3349 for (const auto &Result : LSD->lookup(&NS)) 3350 if ((ND = dyn_cast<NamespaceDecl>(Result))) 3351 break; 3352 3353 if (ND) 3354 for (const auto &Result : ND->lookup(&CXXII)) 3355 if (const auto *FD = dyn_cast<FunctionDecl>(Result)) 3356 return FD; 3357 } 3358 } 3359 3360 return nullptr; 3361 } 3362 3363 /// CreateRuntimeFunction - Create a new runtime function with the specified 3364 /// type and name. 3365 llvm::FunctionCallee 3366 CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy, StringRef Name, 3367 llvm::AttributeList ExtraAttrs, bool Local, 3368 bool AssumeConvergent) { 3369 if (AssumeConvergent) { 3370 ExtraAttrs = 3371 ExtraAttrs.addAttribute(VMContext, llvm::AttributeList::FunctionIndex, 3372 llvm::Attribute::Convergent); 3373 } 3374 3375 llvm::Constant *C = 3376 GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false, 3377 /*DontDefer=*/false, /*IsThunk=*/false, 3378 ExtraAttrs); 3379 3380 if (auto *F = dyn_cast<llvm::Function>(C)) { 3381 if (F->empty()) { 3382 F->setCallingConv(getRuntimeCC()); 3383 3384 // In Windows Itanium environments, try to mark runtime functions 3385 // dllimport. For Mingw and MSVC, don't. We don't really know if the user 3386 // will link their standard library statically or dynamically. Marking 3387 // functions imported when they are not imported can cause linker errors 3388 // and warnings. 3389 if (!Local && getTriple().isWindowsItaniumEnvironment() && 3390 !getCodeGenOpts().LTOVisibilityPublicStd) { 3391 const FunctionDecl *FD = GetRuntimeFunctionDecl(Context, Name); 3392 if (!FD || FD->hasAttr<DLLImportAttr>()) { 3393 F->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass); 3394 F->setLinkage(llvm::GlobalValue::ExternalLinkage); 3395 } 3396 } 3397 setDSOLocal(F); 3398 } 3399 } 3400 3401 return {FTy, C}; 3402 } 3403 3404 /// isTypeConstant - Determine whether an object of this type can be emitted 3405 /// as a constant. 3406 /// 3407 /// If ExcludeCtor is true, the duration when the object's constructor runs 3408 /// will not be considered. The caller will need to verify that the object is 3409 /// not written to during its construction. 3410 bool CodeGenModule::isTypeConstant(QualType Ty, bool ExcludeCtor) { 3411 if (!Ty.isConstant(Context) && !Ty->isReferenceType()) 3412 return false; 3413 3414 if (Context.getLangOpts().CPlusPlus) { 3415 if (const CXXRecordDecl *Record 3416 = Context.getBaseElementType(Ty)->getAsCXXRecordDecl()) 3417 return ExcludeCtor && !Record->hasMutableFields() && 3418 Record->hasTrivialDestructor(); 3419 } 3420 3421 return true; 3422 } 3423 3424 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module, 3425 /// create and return an llvm GlobalVariable with the specified type. If there 3426 /// is something in the module with the specified name, return it potentially 3427 /// bitcasted to the right type. 3428 /// 3429 /// If D is non-null, it specifies a decl that correspond to this. This is used 3430 /// to set the attributes on the global when it is first created. 3431 /// 3432 /// If IsForDefinition is true, it is guaranteed that an actual global with 3433 /// type Ty will be returned, not conversion of a variable with the same 3434 /// mangled name but some other type. 3435 llvm::Constant * 3436 CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, 3437 llvm::PointerType *Ty, 3438 const VarDecl *D, 3439 ForDefinition_t IsForDefinition) { 3440 // Lookup the entry, lazily creating it if necessary. 3441 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 3442 if (Entry) { 3443 if (WeakRefReferences.erase(Entry)) { 3444 if (D && !D->hasAttr<WeakAttr>()) 3445 Entry->setLinkage(llvm::Function::ExternalLinkage); 3446 } 3447 3448 // Handle dropped DLL attributes. 3449 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>()) 3450 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass); 3451 3452 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd && D) 3453 getOpenMPRuntime().registerTargetGlobalVariable(D, Entry); 3454 3455 if (Entry->getType() == Ty) 3456 return Entry; 3457 3458 // If there are two attempts to define the same mangled name, issue an 3459 // error. 3460 if (IsForDefinition && !Entry->isDeclaration()) { 3461 GlobalDecl OtherGD; 3462 const VarDecl *OtherD; 3463 3464 // Check that D is not yet in DiagnosedConflictingDefinitions is required 3465 // to make sure that we issue an error only once. 3466 if (D && lookupRepresentativeDecl(MangledName, OtherGD) && 3467 (D->getCanonicalDecl() != OtherGD.getCanonicalDecl().getDecl()) && 3468 (OtherD = dyn_cast<VarDecl>(OtherGD.getDecl())) && 3469 OtherD->hasInit() && 3470 DiagnosedConflictingDefinitions.insert(D).second) { 3471 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name) 3472 << MangledName; 3473 getDiags().Report(OtherGD.getDecl()->getLocation(), 3474 diag::note_previous_definition); 3475 } 3476 } 3477 3478 // Make sure the result is of the correct type. 3479 if (Entry->getType()->getAddressSpace() != Ty->getAddressSpace()) 3480 return llvm::ConstantExpr::getAddrSpaceCast(Entry, Ty); 3481 3482 // (If global is requested for a definition, we always need to create a new 3483 // global, not just return a bitcast.) 3484 if (!IsForDefinition) 3485 return llvm::ConstantExpr::getBitCast(Entry, Ty); 3486 } 3487 3488 auto AddrSpace = GetGlobalVarAddressSpace(D); 3489 auto TargetAddrSpace = getContext().getTargetAddressSpace(AddrSpace); 3490 3491 auto *GV = new llvm::GlobalVariable( 3492 getModule(), Ty->getElementType(), false, 3493 llvm::GlobalValue::ExternalLinkage, nullptr, MangledName, nullptr, 3494 llvm::GlobalVariable::NotThreadLocal, TargetAddrSpace); 3495 3496 // If we already created a global with the same mangled name (but different 3497 // type) before, take its name and remove it from its parent. 3498 if (Entry) { 3499 GV->takeName(Entry); 3500 3501 if (!Entry->use_empty()) { 3502 llvm::Constant *NewPtrForOldDecl = 3503 llvm::ConstantExpr::getBitCast(GV, Entry->getType()); 3504 Entry->replaceAllUsesWith(NewPtrForOldDecl); 3505 } 3506 3507 Entry->eraseFromParent(); 3508 } 3509 3510 // This is the first use or definition of a mangled name. If there is a 3511 // deferred decl with this name, remember that we need to emit it at the end 3512 // of the file. 3513 auto DDI = DeferredDecls.find(MangledName); 3514 if (DDI != DeferredDecls.end()) { 3515 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 3516 // list, and remove it from DeferredDecls (since we don't need it anymore). 3517 addDeferredDeclToEmit(DDI->second); 3518 DeferredDecls.erase(DDI); 3519 } 3520 3521 // Handle things which are present even on external declarations. 3522 if (D) { 3523 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd) 3524 getOpenMPRuntime().registerTargetGlobalVariable(D, GV); 3525 3526 // FIXME: This code is overly simple and should be merged with other global 3527 // handling. 3528 GV->setConstant(isTypeConstant(D->getType(), false)); 3529 3530 GV->setAlignment(getContext().getDeclAlign(D).getAsAlign()); 3531 3532 setLinkageForGV(GV, D); 3533 3534 if (D->getTLSKind()) { 3535 if (D->getTLSKind() == VarDecl::TLS_Dynamic) 3536 CXXThreadLocals.push_back(D); 3537 setTLSMode(GV, *D); 3538 } 3539 3540 setGVProperties(GV, D); 3541 3542 // If required by the ABI, treat declarations of static data members with 3543 // inline initializers as definitions. 3544 if (getContext().isMSStaticDataMemberInlineDefinition(D)) { 3545 EmitGlobalVarDefinition(D); 3546 } 3547 3548 // Emit section information for extern variables. 3549 if (D->hasExternalStorage()) { 3550 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) 3551 GV->setSection(SA->getName()); 3552 } 3553 3554 // Handle XCore specific ABI requirements. 3555 if (getTriple().getArch() == llvm::Triple::xcore && 3556 D->getLanguageLinkage() == CLanguageLinkage && 3557 D->getType().isConstant(Context) && 3558 isExternallyVisible(D->getLinkageAndVisibility().getLinkage())) 3559 GV->setSection(".cp.rodata"); 3560 3561 // Check if we a have a const declaration with an initializer, we may be 3562 // able to emit it as available_externally to expose it's value to the 3563 // optimizer. 3564 if (Context.getLangOpts().CPlusPlus && GV->hasExternalLinkage() && 3565 D->getType().isConstQualified() && !GV->hasInitializer() && 3566 !D->hasDefinition() && D->hasInit() && !D->hasAttr<DLLImportAttr>()) { 3567 const auto *Record = 3568 Context.getBaseElementType(D->getType())->getAsCXXRecordDecl(); 3569 bool HasMutableFields = Record && Record->hasMutableFields(); 3570 if (!HasMutableFields) { 3571 const VarDecl *InitDecl; 3572 const Expr *InitExpr = D->getAnyInitializer(InitDecl); 3573 if (InitExpr) { 3574 ConstantEmitter emitter(*this); 3575 llvm::Constant *Init = emitter.tryEmitForInitializer(*InitDecl); 3576 if (Init) { 3577 auto *InitType = Init->getType(); 3578 if (GV->getType()->getElementType() != InitType) { 3579 // The type of the initializer does not match the definition. 3580 // This happens when an initializer has a different type from 3581 // the type of the global (because of padding at the end of a 3582 // structure for instance). 3583 GV->setName(StringRef()); 3584 // Make a new global with the correct type, this is now guaranteed 3585 // to work. 3586 auto *NewGV = cast<llvm::GlobalVariable>( 3587 GetAddrOfGlobalVar(D, InitType, IsForDefinition) 3588 ->stripPointerCasts()); 3589 3590 // Erase the old global, since it is no longer used. 3591 GV->eraseFromParent(); 3592 GV = NewGV; 3593 } else { 3594 GV->setInitializer(Init); 3595 GV->setConstant(true); 3596 GV->setLinkage(llvm::GlobalValue::AvailableExternallyLinkage); 3597 } 3598 emitter.finalize(GV); 3599 } 3600 } 3601 } 3602 } 3603 } 3604 3605 if (GV->isDeclaration()) 3606 getTargetCodeGenInfo().setTargetAttributes(D, GV, *this); 3607 3608 LangAS ExpectedAS = 3609 D ? D->getType().getAddressSpace() 3610 : (LangOpts.OpenCL ? LangAS::opencl_global : LangAS::Default); 3611 assert(getContext().getTargetAddressSpace(ExpectedAS) == 3612 Ty->getPointerAddressSpace()); 3613 if (AddrSpace != ExpectedAS) 3614 return getTargetCodeGenInfo().performAddrSpaceCast(*this, GV, AddrSpace, 3615 ExpectedAS, Ty); 3616 3617 return GV; 3618 } 3619 3620 llvm::Constant * 3621 CodeGenModule::GetAddrOfGlobal(GlobalDecl GD, 3622 ForDefinition_t IsForDefinition) { 3623 const Decl *D = GD.getDecl(); 3624 if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D)) 3625 return getAddrOfCXXStructor(GD, /*FnInfo=*/nullptr, /*FnType=*/nullptr, 3626 /*DontDefer=*/false, IsForDefinition); 3627 else if (isa<CXXMethodDecl>(D)) { 3628 auto FInfo = &getTypes().arrangeCXXMethodDeclaration( 3629 cast<CXXMethodDecl>(D)); 3630 auto Ty = getTypes().GetFunctionType(*FInfo); 3631 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false, 3632 IsForDefinition); 3633 } else if (isa<FunctionDecl>(D)) { 3634 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 3635 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 3636 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false, 3637 IsForDefinition); 3638 } else 3639 return GetAddrOfGlobalVar(cast<VarDecl>(D), /*Ty=*/nullptr, 3640 IsForDefinition); 3641 } 3642 3643 llvm::GlobalVariable *CodeGenModule::CreateOrReplaceCXXRuntimeVariable( 3644 StringRef Name, llvm::Type *Ty, llvm::GlobalValue::LinkageTypes Linkage, 3645 unsigned Alignment) { 3646 llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name); 3647 llvm::GlobalVariable *OldGV = nullptr; 3648 3649 if (GV) { 3650 // Check if the variable has the right type. 3651 if (GV->getType()->getElementType() == Ty) 3652 return GV; 3653 3654 // Because C++ name mangling, the only way we can end up with an already 3655 // existing global with the same name is if it has been declared extern "C". 3656 assert(GV->isDeclaration() && "Declaration has wrong type!"); 3657 OldGV = GV; 3658 } 3659 3660 // Create a new variable. 3661 GV = new llvm::GlobalVariable(getModule(), Ty, /*isConstant=*/true, 3662 Linkage, nullptr, Name); 3663 3664 if (OldGV) { 3665 // Replace occurrences of the old variable if needed. 3666 GV->takeName(OldGV); 3667 3668 if (!OldGV->use_empty()) { 3669 llvm::Constant *NewPtrForOldDecl = 3670 llvm::ConstantExpr::getBitCast(GV, OldGV->getType()); 3671 OldGV->replaceAllUsesWith(NewPtrForOldDecl); 3672 } 3673 3674 OldGV->eraseFromParent(); 3675 } 3676 3677 if (supportsCOMDAT() && GV->isWeakForLinker() && 3678 !GV->hasAvailableExternallyLinkage()) 3679 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 3680 3681 GV->setAlignment(llvm::MaybeAlign(Alignment)); 3682 3683 return GV; 3684 } 3685 3686 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the 3687 /// given global variable. If Ty is non-null and if the global doesn't exist, 3688 /// then it will be created with the specified type instead of whatever the 3689 /// normal requested type would be. If IsForDefinition is true, it is guaranteed 3690 /// that an actual global with type Ty will be returned, not conversion of a 3691 /// variable with the same mangled name but some other type. 3692 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D, 3693 llvm::Type *Ty, 3694 ForDefinition_t IsForDefinition) { 3695 assert(D->hasGlobalStorage() && "Not a global variable"); 3696 QualType ASTTy = D->getType(); 3697 if (!Ty) 3698 Ty = getTypes().ConvertTypeForMem(ASTTy); 3699 3700 llvm::PointerType *PTy = 3701 llvm::PointerType::get(Ty, getContext().getTargetAddressSpace(ASTTy)); 3702 3703 StringRef MangledName = getMangledName(D); 3704 return GetOrCreateLLVMGlobal(MangledName, PTy, D, IsForDefinition); 3705 } 3706 3707 /// CreateRuntimeVariable - Create a new runtime global variable with the 3708 /// specified type and name. 3709 llvm::Constant * 3710 CodeGenModule::CreateRuntimeVariable(llvm::Type *Ty, 3711 StringRef Name) { 3712 auto PtrTy = 3713 getContext().getLangOpts().OpenCL 3714 ? llvm::PointerType::get( 3715 Ty, getContext().getTargetAddressSpace(LangAS::opencl_global)) 3716 : llvm::PointerType::getUnqual(Ty); 3717 auto *Ret = GetOrCreateLLVMGlobal(Name, PtrTy, nullptr); 3718 setDSOLocal(cast<llvm::GlobalValue>(Ret->stripPointerCasts())); 3719 return Ret; 3720 } 3721 3722 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) { 3723 assert(!D->getInit() && "Cannot emit definite definitions here!"); 3724 3725 StringRef MangledName = getMangledName(D); 3726 llvm::GlobalValue *GV = GetGlobalValue(MangledName); 3727 3728 // We already have a definition, not declaration, with the same mangled name. 3729 // Emitting of declaration is not required (and actually overwrites emitted 3730 // definition). 3731 if (GV && !GV->isDeclaration()) 3732 return; 3733 3734 // If we have not seen a reference to this variable yet, place it into the 3735 // deferred declarations table to be emitted if needed later. 3736 if (!MustBeEmitted(D) && !GV) { 3737 DeferredDecls[MangledName] = D; 3738 return; 3739 } 3740 3741 // The tentative definition is the only definition. 3742 EmitGlobalVarDefinition(D); 3743 } 3744 3745 void CodeGenModule::EmitExternalDeclaration(const VarDecl *D) { 3746 EmitExternalVarDeclaration(D); 3747 } 3748 3749 CharUnits CodeGenModule::GetTargetTypeStoreSize(llvm::Type *Ty) const { 3750 return Context.toCharUnitsFromBits( 3751 getDataLayout().getTypeStoreSizeInBits(Ty)); 3752 } 3753 3754 LangAS CodeGenModule::GetGlobalVarAddressSpace(const VarDecl *D) { 3755 LangAS AddrSpace = LangAS::Default; 3756 if (LangOpts.OpenCL) { 3757 AddrSpace = D ? D->getType().getAddressSpace() : LangAS::opencl_global; 3758 assert(AddrSpace == LangAS::opencl_global || 3759 AddrSpace == LangAS::opencl_constant || 3760 AddrSpace == LangAS::opencl_local || 3761 AddrSpace >= LangAS::FirstTargetAddressSpace); 3762 return AddrSpace; 3763 } 3764 3765 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) { 3766 if (D && D->hasAttr<CUDAConstantAttr>()) 3767 return LangAS::cuda_constant; 3768 else if (D && D->hasAttr<CUDASharedAttr>()) 3769 return LangAS::cuda_shared; 3770 else if (D && D->hasAttr<CUDADeviceAttr>()) 3771 return LangAS::cuda_device; 3772 else if (D && D->getType().isConstQualified()) 3773 return LangAS::cuda_constant; 3774 else 3775 return LangAS::cuda_device; 3776 } 3777 3778 if (LangOpts.OpenMP) { 3779 LangAS AS; 3780 if (OpenMPRuntime->hasAllocateAttributeForGlobalVar(D, AS)) 3781 return AS; 3782 } 3783 return getTargetCodeGenInfo().getGlobalVarAddressSpace(*this, D); 3784 } 3785 3786 LangAS CodeGenModule::getStringLiteralAddressSpace() const { 3787 // OpenCL v1.2 s6.5.3: a string literal is in the constant address space. 3788 if (LangOpts.OpenCL) 3789 return LangAS::opencl_constant; 3790 if (auto AS = getTarget().getConstantAddressSpace()) 3791 return AS.getValue(); 3792 return LangAS::Default; 3793 } 3794 3795 // In address space agnostic languages, string literals are in default address 3796 // space in AST. However, certain targets (e.g. amdgcn) request them to be 3797 // emitted in constant address space in LLVM IR. To be consistent with other 3798 // parts of AST, string literal global variables in constant address space 3799 // need to be casted to default address space before being put into address 3800 // map and referenced by other part of CodeGen. 3801 // In OpenCL, string literals are in constant address space in AST, therefore 3802 // they should not be casted to default address space. 3803 static llvm::Constant * 3804 castStringLiteralToDefaultAddressSpace(CodeGenModule &CGM, 3805 llvm::GlobalVariable *GV) { 3806 llvm::Constant *Cast = GV; 3807 if (!CGM.getLangOpts().OpenCL) { 3808 if (auto AS = CGM.getTarget().getConstantAddressSpace()) { 3809 if (AS != LangAS::Default) 3810 Cast = CGM.getTargetCodeGenInfo().performAddrSpaceCast( 3811 CGM, GV, AS.getValue(), LangAS::Default, 3812 GV->getValueType()->getPointerTo( 3813 CGM.getContext().getTargetAddressSpace(LangAS::Default))); 3814 } 3815 } 3816 return Cast; 3817 } 3818 3819 template<typename SomeDecl> 3820 void CodeGenModule::MaybeHandleStaticInExternC(const SomeDecl *D, 3821 llvm::GlobalValue *GV) { 3822 if (!getLangOpts().CPlusPlus) 3823 return; 3824 3825 // Must have 'used' attribute, or else inline assembly can't rely on 3826 // the name existing. 3827 if (!D->template hasAttr<UsedAttr>()) 3828 return; 3829 3830 // Must have internal linkage and an ordinary name. 3831 if (!D->getIdentifier() || D->getFormalLinkage() != InternalLinkage) 3832 return; 3833 3834 // Must be in an extern "C" context. Entities declared directly within 3835 // a record are not extern "C" even if the record is in such a context. 3836 const SomeDecl *First = D->getFirstDecl(); 3837 if (First->getDeclContext()->isRecord() || !First->isInExternCContext()) 3838 return; 3839 3840 // OK, this is an internal linkage entity inside an extern "C" linkage 3841 // specification. Make a note of that so we can give it the "expected" 3842 // mangled name if nothing else is using that name. 3843 std::pair<StaticExternCMap::iterator, bool> R = 3844 StaticExternCValues.insert(std::make_pair(D->getIdentifier(), GV)); 3845 3846 // If we have multiple internal linkage entities with the same name 3847 // in extern "C" regions, none of them gets that name. 3848 if (!R.second) 3849 R.first->second = nullptr; 3850 } 3851 3852 static bool shouldBeInCOMDAT(CodeGenModule &CGM, const Decl &D) { 3853 if (!CGM.supportsCOMDAT()) 3854 return false; 3855 3856 // Do not set COMDAT attribute for CUDA/HIP stub functions to prevent 3857 // them being "merged" by the COMDAT Folding linker optimization. 3858 if (D.hasAttr<CUDAGlobalAttr>()) 3859 return false; 3860 3861 if (D.hasAttr<SelectAnyAttr>()) 3862 return true; 3863 3864 GVALinkage Linkage; 3865 if (auto *VD = dyn_cast<VarDecl>(&D)) 3866 Linkage = CGM.getContext().GetGVALinkageForVariable(VD); 3867 else 3868 Linkage = CGM.getContext().GetGVALinkageForFunction(cast<FunctionDecl>(&D)); 3869 3870 switch (Linkage) { 3871 case GVA_Internal: 3872 case GVA_AvailableExternally: 3873 case GVA_StrongExternal: 3874 return false; 3875 case GVA_DiscardableODR: 3876 case GVA_StrongODR: 3877 return true; 3878 } 3879 llvm_unreachable("No such linkage"); 3880 } 3881 3882 void CodeGenModule::maybeSetTrivialComdat(const Decl &D, 3883 llvm::GlobalObject &GO) { 3884 if (!shouldBeInCOMDAT(*this, D)) 3885 return; 3886 GO.setComdat(TheModule.getOrInsertComdat(GO.getName())); 3887 } 3888 3889 /// Pass IsTentative as true if you want to create a tentative definition. 3890 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D, 3891 bool IsTentative) { 3892 // OpenCL global variables of sampler type are translated to function calls, 3893 // therefore no need to be translated. 3894 QualType ASTTy = D->getType(); 3895 if (getLangOpts().OpenCL && ASTTy->isSamplerT()) 3896 return; 3897 3898 // If this is OpenMP device, check if it is legal to emit this global 3899 // normally. 3900 if (LangOpts.OpenMPIsDevice && OpenMPRuntime && 3901 OpenMPRuntime->emitTargetGlobalVariable(D)) 3902 return; 3903 3904 llvm::Constant *Init = nullptr; 3905 bool NeedsGlobalCtor = false; 3906 bool NeedsGlobalDtor = 3907 D->needsDestruction(getContext()) == QualType::DK_cxx_destructor; 3908 3909 const VarDecl *InitDecl; 3910 const Expr *InitExpr = D->getAnyInitializer(InitDecl); 3911 3912 Optional<ConstantEmitter> emitter; 3913 3914 // CUDA E.2.4.1 "__shared__ variables cannot have an initialization 3915 // as part of their declaration." Sema has already checked for 3916 // error cases, so we just need to set Init to UndefValue. 3917 bool IsCUDASharedVar = 3918 getLangOpts().CUDAIsDevice && D->hasAttr<CUDASharedAttr>(); 3919 // Shadows of initialized device-side global variables are also left 3920 // undefined. 3921 bool IsCUDAShadowVar = 3922 !getLangOpts().CUDAIsDevice && 3923 (D->hasAttr<CUDAConstantAttr>() || D->hasAttr<CUDADeviceAttr>() || 3924 D->hasAttr<CUDASharedAttr>()); 3925 // HIP pinned shadow of initialized host-side global variables are also 3926 // left undefined. 3927 bool IsHIPPinnedShadowVar = 3928 getLangOpts().CUDAIsDevice && D->hasAttr<HIPPinnedShadowAttr>(); 3929 if (getLangOpts().CUDA && 3930 (IsCUDASharedVar || IsCUDAShadowVar || IsHIPPinnedShadowVar)) 3931 Init = llvm::UndefValue::get(getTypes().ConvertType(ASTTy)); 3932 else if (!InitExpr) { 3933 // This is a tentative definition; tentative definitions are 3934 // implicitly initialized with { 0 }. 3935 // 3936 // Note that tentative definitions are only emitted at the end of 3937 // a translation unit, so they should never have incomplete 3938 // type. In addition, EmitTentativeDefinition makes sure that we 3939 // never attempt to emit a tentative definition if a real one 3940 // exists. A use may still exists, however, so we still may need 3941 // to do a RAUW. 3942 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type"); 3943 Init = EmitNullConstant(D->getType()); 3944 } else { 3945 initializedGlobalDecl = GlobalDecl(D); 3946 emitter.emplace(*this); 3947 Init = emitter->tryEmitForInitializer(*InitDecl); 3948 3949 if (!Init) { 3950 QualType T = InitExpr->getType(); 3951 if (D->getType()->isReferenceType()) 3952 T = D->getType(); 3953 3954 if (getLangOpts().CPlusPlus) { 3955 Init = EmitNullConstant(T); 3956 NeedsGlobalCtor = true; 3957 } else { 3958 ErrorUnsupported(D, "static initializer"); 3959 Init = llvm::UndefValue::get(getTypes().ConvertType(T)); 3960 } 3961 } else { 3962 // We don't need an initializer, so remove the entry for the delayed 3963 // initializer position (just in case this entry was delayed) if we 3964 // also don't need to register a destructor. 3965 if (getLangOpts().CPlusPlus && !NeedsGlobalDtor) 3966 DelayedCXXInitPosition.erase(D); 3967 } 3968 } 3969 3970 llvm::Type* InitType = Init->getType(); 3971 llvm::Constant *Entry = 3972 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)); 3973 3974 // Strip off pointer casts if we got them. 3975 Entry = Entry->stripPointerCasts(); 3976 3977 // Entry is now either a Function or GlobalVariable. 3978 auto *GV = dyn_cast<llvm::GlobalVariable>(Entry); 3979 3980 // We have a definition after a declaration with the wrong type. 3981 // We must make a new GlobalVariable* and update everything that used OldGV 3982 // (a declaration or tentative definition) with the new GlobalVariable* 3983 // (which will be a definition). 3984 // 3985 // This happens if there is a prototype for a global (e.g. 3986 // "extern int x[];") and then a definition of a different type (e.g. 3987 // "int x[10];"). This also happens when an initializer has a different type 3988 // from the type of the global (this happens with unions). 3989 if (!GV || GV->getType()->getElementType() != InitType || 3990 GV->getType()->getAddressSpace() != 3991 getContext().getTargetAddressSpace(GetGlobalVarAddressSpace(D))) { 3992 3993 // Move the old entry aside so that we'll create a new one. 3994 Entry->setName(StringRef()); 3995 3996 // Make a new global with the correct type, this is now guaranteed to work. 3997 GV = cast<llvm::GlobalVariable>( 3998 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)) 3999 ->stripPointerCasts()); 4000 4001 // Replace all uses of the old global with the new global 4002 llvm::Constant *NewPtrForOldDecl = 4003 llvm::ConstantExpr::getBitCast(GV, Entry->getType()); 4004 Entry->replaceAllUsesWith(NewPtrForOldDecl); 4005 4006 // Erase the old global, since it is no longer used. 4007 cast<llvm::GlobalValue>(Entry)->eraseFromParent(); 4008 } 4009 4010 MaybeHandleStaticInExternC(D, GV); 4011 4012 if (D->hasAttr<AnnotateAttr>()) 4013 AddGlobalAnnotations(D, GV); 4014 4015 // Set the llvm linkage type as appropriate. 4016 llvm::GlobalValue::LinkageTypes Linkage = 4017 getLLVMLinkageVarDefinition(D, GV->isConstant()); 4018 4019 // CUDA B.2.1 "The __device__ qualifier declares a variable that resides on 4020 // the device. [...]" 4021 // CUDA B.2.2 "The __constant__ qualifier, optionally used together with 4022 // __device__, declares a variable that: [...] 4023 // Is accessible from all the threads within the grid and from the host 4024 // through the runtime library (cudaGetSymbolAddress() / cudaGetSymbolSize() 4025 // / cudaMemcpyToSymbol() / cudaMemcpyFromSymbol())." 4026 if (GV && LangOpts.CUDA) { 4027 if (LangOpts.CUDAIsDevice) { 4028 if (Linkage != llvm::GlobalValue::InternalLinkage && 4029 (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>())) 4030 GV->setExternallyInitialized(true); 4031 } else { 4032 // Host-side shadows of external declarations of device-side 4033 // global variables become internal definitions. These have to 4034 // be internal in order to prevent name conflicts with global 4035 // host variables with the same name in a different TUs. 4036 if (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>() || 4037 D->hasAttr<HIPPinnedShadowAttr>()) { 4038 Linkage = llvm::GlobalValue::InternalLinkage; 4039 4040 // Shadow variables and their properties must be registered 4041 // with CUDA runtime. 4042 unsigned Flags = 0; 4043 if (!D->hasDefinition()) 4044 Flags |= CGCUDARuntime::ExternDeviceVar; 4045 if (D->hasAttr<CUDAConstantAttr>()) 4046 Flags |= CGCUDARuntime::ConstantDeviceVar; 4047 // Extern global variables will be registered in the TU where they are 4048 // defined. 4049 if (!D->hasExternalStorage()) 4050 getCUDARuntime().registerDeviceVar(D, *GV, Flags); 4051 } else if (D->hasAttr<CUDASharedAttr>()) 4052 // __shared__ variables are odd. Shadows do get created, but 4053 // they are not registered with the CUDA runtime, so they 4054 // can't really be used to access their device-side 4055 // counterparts. It's not clear yet whether it's nvcc's bug or 4056 // a feature, but we've got to do the same for compatibility. 4057 Linkage = llvm::GlobalValue::InternalLinkage; 4058 } 4059 } 4060 4061 if (!IsHIPPinnedShadowVar) 4062 GV->setInitializer(Init); 4063 if (emitter) emitter->finalize(GV); 4064 4065 // If it is safe to mark the global 'constant', do so now. 4066 GV->setConstant(!NeedsGlobalCtor && !NeedsGlobalDtor && 4067 isTypeConstant(D->getType(), true)); 4068 4069 // If it is in a read-only section, mark it 'constant'. 4070 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) { 4071 const ASTContext::SectionInfo &SI = Context.SectionInfos[SA->getName()]; 4072 if ((SI.SectionFlags & ASTContext::PSF_Write) == 0) 4073 GV->setConstant(true); 4074 } 4075 4076 GV->setAlignment(getContext().getDeclAlign(D).getAsAlign()); 4077 4078 // On Darwin, if the normal linkage of a C++ thread_local variable is 4079 // LinkOnce or Weak, we keep the normal linkage to prevent multiple 4080 // copies within a linkage unit; otherwise, the backing variable has 4081 // internal linkage and all accesses should just be calls to the 4082 // Itanium-specified entry point, which has the normal linkage of the 4083 // variable. This is to preserve the ability to change the implementation 4084 // behind the scenes. 4085 if (!D->isStaticLocal() && D->getTLSKind() == VarDecl::TLS_Dynamic && 4086 Context.getTargetInfo().getTriple().isOSDarwin() && 4087 !llvm::GlobalVariable::isLinkOnceLinkage(Linkage) && 4088 !llvm::GlobalVariable::isWeakLinkage(Linkage)) 4089 Linkage = llvm::GlobalValue::InternalLinkage; 4090 4091 GV->setLinkage(Linkage); 4092 if (D->hasAttr<DLLImportAttr>()) 4093 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass); 4094 else if (D->hasAttr<DLLExportAttr>()) 4095 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass); 4096 else 4097 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass); 4098 4099 if (Linkage == llvm::GlobalVariable::CommonLinkage) { 4100 // common vars aren't constant even if declared const. 4101 GV->setConstant(false); 4102 // Tentative definition of global variables may be initialized with 4103 // non-zero null pointers. In this case they should have weak linkage 4104 // since common linkage must have zero initializer and must not have 4105 // explicit section therefore cannot have non-zero initial value. 4106 if (!GV->getInitializer()->isNullValue()) 4107 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 4108 } 4109 4110 setNonAliasAttributes(D, GV); 4111 4112 if (D->getTLSKind() && !GV->isThreadLocal()) { 4113 if (D->getTLSKind() == VarDecl::TLS_Dynamic) 4114 CXXThreadLocals.push_back(D); 4115 setTLSMode(GV, *D); 4116 } 4117 4118 maybeSetTrivialComdat(*D, *GV); 4119 4120 // Emit the initializer function if necessary. 4121 if (NeedsGlobalCtor || NeedsGlobalDtor) 4122 EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor); 4123 4124 SanitizerMD->reportGlobalToASan(GV, *D, NeedsGlobalCtor); 4125 4126 // Emit global variable debug information. 4127 if (CGDebugInfo *DI = getModuleDebugInfo()) 4128 if (getCodeGenOpts().hasReducedDebugInfo()) 4129 DI->EmitGlobalVariable(GV, D); 4130 } 4131 4132 void CodeGenModule::EmitExternalVarDeclaration(const VarDecl *D) { 4133 if (CGDebugInfo *DI = getModuleDebugInfo()) 4134 if (getCodeGenOpts().hasReducedDebugInfo()) { 4135 QualType ASTTy = D->getType(); 4136 llvm::Type *Ty = getTypes().ConvertTypeForMem(D->getType()); 4137 llvm::PointerType *PTy = 4138 llvm::PointerType::get(Ty, getContext().getTargetAddressSpace(ASTTy)); 4139 llvm::Constant *GV = GetOrCreateLLVMGlobal(D->getName(), PTy, D); 4140 DI->EmitExternalVariable( 4141 cast<llvm::GlobalVariable>(GV->stripPointerCasts()), D); 4142 } 4143 } 4144 4145 static bool isVarDeclStrongDefinition(const ASTContext &Context, 4146 CodeGenModule &CGM, const VarDecl *D, 4147 bool NoCommon) { 4148 // Don't give variables common linkage if -fno-common was specified unless it 4149 // was overridden by a NoCommon attribute. 4150 if ((NoCommon || D->hasAttr<NoCommonAttr>()) && !D->hasAttr<CommonAttr>()) 4151 return true; 4152 4153 // C11 6.9.2/2: 4154 // A declaration of an identifier for an object that has file scope without 4155 // an initializer, and without a storage-class specifier or with the 4156 // storage-class specifier static, constitutes a tentative definition. 4157 if (D->getInit() || D->hasExternalStorage()) 4158 return true; 4159 4160 // A variable cannot be both common and exist in a section. 4161 if (D->hasAttr<SectionAttr>()) 4162 return true; 4163 4164 // A variable cannot be both common and exist in a section. 4165 // We don't try to determine which is the right section in the front-end. 4166 // If no specialized section name is applicable, it will resort to default. 4167 if (D->hasAttr<PragmaClangBSSSectionAttr>() || 4168 D->hasAttr<PragmaClangDataSectionAttr>() || 4169 D->hasAttr<PragmaClangRelroSectionAttr>() || 4170 D->hasAttr<PragmaClangRodataSectionAttr>()) 4171 return true; 4172 4173 // Thread local vars aren't considered common linkage. 4174 if (D->getTLSKind()) 4175 return true; 4176 4177 // Tentative definitions marked with WeakImportAttr are true definitions. 4178 if (D->hasAttr<WeakImportAttr>()) 4179 return true; 4180 4181 // A variable cannot be both common and exist in a comdat. 4182 if (shouldBeInCOMDAT(CGM, *D)) 4183 return true; 4184 4185 // Declarations with a required alignment do not have common linkage in MSVC 4186 // mode. 4187 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) { 4188 if (D->hasAttr<AlignedAttr>()) 4189 return true; 4190 QualType VarType = D->getType(); 4191 if (Context.isAlignmentRequired(VarType)) 4192 return true; 4193 4194 if (const auto *RT = VarType->getAs<RecordType>()) { 4195 const RecordDecl *RD = RT->getDecl(); 4196 for (const FieldDecl *FD : RD->fields()) { 4197 if (FD->isBitField()) 4198 continue; 4199 if (FD->hasAttr<AlignedAttr>()) 4200 return true; 4201 if (Context.isAlignmentRequired(FD->getType())) 4202 return true; 4203 } 4204 } 4205 } 4206 4207 // Microsoft's link.exe doesn't support alignments greater than 32 bytes for 4208 // common symbols, so symbols with greater alignment requirements cannot be 4209 // common. 4210 // Other COFF linkers (ld.bfd and LLD) support arbitrary power-of-two 4211 // alignments for common symbols via the aligncomm directive, so this 4212 // restriction only applies to MSVC environments. 4213 if (Context.getTargetInfo().getTriple().isKnownWindowsMSVCEnvironment() && 4214 Context.getTypeAlignIfKnown(D->getType()) > 4215 Context.toBits(CharUnits::fromQuantity(32))) 4216 return true; 4217 4218 return false; 4219 } 4220 4221 llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageForDeclarator( 4222 const DeclaratorDecl *D, GVALinkage Linkage, bool IsConstantVariable) { 4223 if (Linkage == GVA_Internal) 4224 return llvm::Function::InternalLinkage; 4225 4226 if (D->hasAttr<WeakAttr>()) { 4227 if (IsConstantVariable) 4228 return llvm::GlobalVariable::WeakODRLinkage; 4229 else 4230 return llvm::GlobalVariable::WeakAnyLinkage; 4231 } 4232 4233 if (const auto *FD = D->getAsFunction()) 4234 if (FD->isMultiVersion() && Linkage == GVA_AvailableExternally) 4235 return llvm::GlobalVariable::LinkOnceAnyLinkage; 4236 4237 // We are guaranteed to have a strong definition somewhere else, 4238 // so we can use available_externally linkage. 4239 if (Linkage == GVA_AvailableExternally) 4240 return llvm::GlobalValue::AvailableExternallyLinkage; 4241 4242 // Note that Apple's kernel linker doesn't support symbol 4243 // coalescing, so we need to avoid linkonce and weak linkages there. 4244 // Normally, this means we just map to internal, but for explicit 4245 // instantiations we'll map to external. 4246 4247 // In C++, the compiler has to emit a definition in every translation unit 4248 // that references the function. We should use linkonce_odr because 4249 // a) if all references in this translation unit are optimized away, we 4250 // don't need to codegen it. b) if the function persists, it needs to be 4251 // merged with other definitions. c) C++ has the ODR, so we know the 4252 // definition is dependable. 4253 if (Linkage == GVA_DiscardableODR) 4254 return !Context.getLangOpts().AppleKext ? llvm::Function::LinkOnceODRLinkage 4255 : llvm::Function::InternalLinkage; 4256 4257 // An explicit instantiation of a template has weak linkage, since 4258 // explicit instantiations can occur in multiple translation units 4259 // and must all be equivalent. However, we are not allowed to 4260 // throw away these explicit instantiations. 4261 // 4262 // We don't currently support CUDA device code spread out across multiple TUs, 4263 // so say that CUDA templates are either external (for kernels) or internal. 4264 // This lets llvm perform aggressive inter-procedural optimizations. 4265 if (Linkage == GVA_StrongODR) { 4266 if (Context.getLangOpts().AppleKext) 4267 return llvm::Function::ExternalLinkage; 4268 if (Context.getLangOpts().CUDA && Context.getLangOpts().CUDAIsDevice) 4269 return D->hasAttr<CUDAGlobalAttr>() ? llvm::Function::ExternalLinkage 4270 : llvm::Function::InternalLinkage; 4271 return llvm::Function::WeakODRLinkage; 4272 } 4273 4274 // C++ doesn't have tentative definitions and thus cannot have common 4275 // linkage. 4276 if (!getLangOpts().CPlusPlus && isa<VarDecl>(D) && 4277 !isVarDeclStrongDefinition(Context, *this, cast<VarDecl>(D), 4278 CodeGenOpts.NoCommon)) 4279 return llvm::GlobalVariable::CommonLinkage; 4280 4281 // selectany symbols are externally visible, so use weak instead of 4282 // linkonce. MSVC optimizes away references to const selectany globals, so 4283 // all definitions should be the same and ODR linkage should be used. 4284 // http://msdn.microsoft.com/en-us/library/5tkz6s71.aspx 4285 if (D->hasAttr<SelectAnyAttr>()) 4286 return llvm::GlobalVariable::WeakODRLinkage; 4287 4288 // Otherwise, we have strong external linkage. 4289 assert(Linkage == GVA_StrongExternal); 4290 return llvm::GlobalVariable::ExternalLinkage; 4291 } 4292 4293 llvm::GlobalValue::LinkageTypes CodeGenModule::getLLVMLinkageVarDefinition( 4294 const VarDecl *VD, bool IsConstant) { 4295 GVALinkage Linkage = getContext().GetGVALinkageForVariable(VD); 4296 return getLLVMLinkageForDeclarator(VD, Linkage, IsConstant); 4297 } 4298 4299 /// Replace the uses of a function that was declared with a non-proto type. 4300 /// We want to silently drop extra arguments from call sites 4301 static void replaceUsesOfNonProtoConstant(llvm::Constant *old, 4302 llvm::Function *newFn) { 4303 // Fast path. 4304 if (old->use_empty()) return; 4305 4306 llvm::Type *newRetTy = newFn->getReturnType(); 4307 SmallVector<llvm::Value*, 4> newArgs; 4308 SmallVector<llvm::OperandBundleDef, 1> newBundles; 4309 4310 for (llvm::Value::use_iterator ui = old->use_begin(), ue = old->use_end(); 4311 ui != ue; ) { 4312 llvm::Value::use_iterator use = ui++; // Increment before the use is erased. 4313 llvm::User *user = use->getUser(); 4314 4315 // Recognize and replace uses of bitcasts. Most calls to 4316 // unprototyped functions will use bitcasts. 4317 if (auto *bitcast = dyn_cast<llvm::ConstantExpr>(user)) { 4318 if (bitcast->getOpcode() == llvm::Instruction::BitCast) 4319 replaceUsesOfNonProtoConstant(bitcast, newFn); 4320 continue; 4321 } 4322 4323 // Recognize calls to the function. 4324 llvm::CallBase *callSite = dyn_cast<llvm::CallBase>(user); 4325 if (!callSite) continue; 4326 if (!callSite->isCallee(&*use)) 4327 continue; 4328 4329 // If the return types don't match exactly, then we can't 4330 // transform this call unless it's dead. 4331 if (callSite->getType() != newRetTy && !callSite->use_empty()) 4332 continue; 4333 4334 // Get the call site's attribute list. 4335 SmallVector<llvm::AttributeSet, 8> newArgAttrs; 4336 llvm::AttributeList oldAttrs = callSite->getAttributes(); 4337 4338 // If the function was passed too few arguments, don't transform. 4339 unsigned newNumArgs = newFn->arg_size(); 4340 if (callSite->arg_size() < newNumArgs) 4341 continue; 4342 4343 // If extra arguments were passed, we silently drop them. 4344 // If any of the types mismatch, we don't transform. 4345 unsigned argNo = 0; 4346 bool dontTransform = false; 4347 for (llvm::Argument &A : newFn->args()) { 4348 if (callSite->getArgOperand(argNo)->getType() != A.getType()) { 4349 dontTransform = true; 4350 break; 4351 } 4352 4353 // Add any parameter attributes. 4354 newArgAttrs.push_back(oldAttrs.getParamAttributes(argNo)); 4355 argNo++; 4356 } 4357 if (dontTransform) 4358 continue; 4359 4360 // Okay, we can transform this. Create the new call instruction and copy 4361 // over the required information. 4362 newArgs.append(callSite->arg_begin(), callSite->arg_begin() + argNo); 4363 4364 // Copy over any operand bundles. 4365 callSite->getOperandBundlesAsDefs(newBundles); 4366 4367 llvm::CallBase *newCall; 4368 if (dyn_cast<llvm::CallInst>(callSite)) { 4369 newCall = 4370 llvm::CallInst::Create(newFn, newArgs, newBundles, "", callSite); 4371 } else { 4372 auto *oldInvoke = cast<llvm::InvokeInst>(callSite); 4373 newCall = llvm::InvokeInst::Create(newFn, oldInvoke->getNormalDest(), 4374 oldInvoke->getUnwindDest(), newArgs, 4375 newBundles, "", callSite); 4376 } 4377 newArgs.clear(); // for the next iteration 4378 4379 if (!newCall->getType()->isVoidTy()) 4380 newCall->takeName(callSite); 4381 newCall->setAttributes(llvm::AttributeList::get( 4382 newFn->getContext(), oldAttrs.getFnAttributes(), 4383 oldAttrs.getRetAttributes(), newArgAttrs)); 4384 newCall->setCallingConv(callSite->getCallingConv()); 4385 4386 // Finally, remove the old call, replacing any uses with the new one. 4387 if (!callSite->use_empty()) 4388 callSite->replaceAllUsesWith(newCall); 4389 4390 // Copy debug location attached to CI. 4391 if (callSite->getDebugLoc()) 4392 newCall->setDebugLoc(callSite->getDebugLoc()); 4393 4394 callSite->eraseFromParent(); 4395 } 4396 } 4397 4398 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we 4399 /// implement a function with no prototype, e.g. "int foo() {}". If there are 4400 /// existing call uses of the old function in the module, this adjusts them to 4401 /// call the new function directly. 4402 /// 4403 /// This is not just a cleanup: the always_inline pass requires direct calls to 4404 /// functions to be able to inline them. If there is a bitcast in the way, it 4405 /// won't inline them. Instcombine normally deletes these calls, but it isn't 4406 /// run at -O0. 4407 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 4408 llvm::Function *NewFn) { 4409 // If we're redefining a global as a function, don't transform it. 4410 if (!isa<llvm::Function>(Old)) return; 4411 4412 replaceUsesOfNonProtoConstant(Old, NewFn); 4413 } 4414 4415 void CodeGenModule::HandleCXXStaticMemberVarInstantiation(VarDecl *VD) { 4416 auto DK = VD->isThisDeclarationADefinition(); 4417 if (DK == VarDecl::Definition && VD->hasAttr<DLLImportAttr>()) 4418 return; 4419 4420 TemplateSpecializationKind TSK = VD->getTemplateSpecializationKind(); 4421 // If we have a definition, this might be a deferred decl. If the 4422 // instantiation is explicit, make sure we emit it at the end. 4423 if (VD->getDefinition() && TSK == TSK_ExplicitInstantiationDefinition) 4424 GetAddrOfGlobalVar(VD); 4425 4426 EmitTopLevelDecl(VD); 4427 } 4428 4429 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD, 4430 llvm::GlobalValue *GV) { 4431 // Check if this must be emitted as declare variant. 4432 if (LangOpts.OpenMP && OpenMPRuntime && 4433 OpenMPRuntime->emitDeclareVariant(GD, /*IsForDefinition=*/true)) 4434 return; 4435 4436 const auto *D = cast<FunctionDecl>(GD.getDecl()); 4437 4438 // Compute the function info and LLVM type. 4439 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4440 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 4441 4442 // Get or create the prototype for the function. 4443 if (!GV || (GV->getType()->getElementType() != Ty)) 4444 GV = cast<llvm::GlobalValue>(GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, 4445 /*DontDefer=*/true, 4446 ForDefinition)); 4447 4448 // Already emitted. 4449 if (!GV->isDeclaration()) 4450 return; 4451 4452 // We need to set linkage and visibility on the function before 4453 // generating code for it because various parts of IR generation 4454 // want to propagate this information down (e.g. to local static 4455 // declarations). 4456 auto *Fn = cast<llvm::Function>(GV); 4457 setFunctionLinkage(GD, Fn); 4458 4459 // FIXME: this is redundant with part of setFunctionDefinitionAttributes 4460 setGVProperties(Fn, GD); 4461 4462 MaybeHandleStaticInExternC(D, Fn); 4463 4464 4465 maybeSetTrivialComdat(*D, *Fn); 4466 4467 CodeGenFunction(*this).GenerateCode(D, Fn, FI); 4468 4469 setNonAliasAttributes(GD, Fn); 4470 SetLLVMFunctionAttributesForDefinition(D, Fn); 4471 4472 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>()) 4473 AddGlobalCtor(Fn, CA->getPriority()); 4474 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>()) 4475 AddGlobalDtor(Fn, DA->getPriority()); 4476 if (D->hasAttr<AnnotateAttr>()) 4477 AddGlobalAnnotations(D, Fn); 4478 } 4479 4480 void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) { 4481 const auto *D = cast<ValueDecl>(GD.getDecl()); 4482 const AliasAttr *AA = D->getAttr<AliasAttr>(); 4483 assert(AA && "Not an alias?"); 4484 4485 StringRef MangledName = getMangledName(GD); 4486 4487 if (AA->getAliasee() == MangledName) { 4488 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0; 4489 return; 4490 } 4491 4492 // If there is a definition in the module, then it wins over the alias. 4493 // This is dubious, but allow it to be safe. Just ignore the alias. 4494 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 4495 if (Entry && !Entry->isDeclaration()) 4496 return; 4497 4498 Aliases.push_back(GD); 4499 4500 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 4501 4502 // Create a reference to the named value. This ensures that it is emitted 4503 // if a deferred decl. 4504 llvm::Constant *Aliasee; 4505 llvm::GlobalValue::LinkageTypes LT; 4506 if (isa<llvm::FunctionType>(DeclTy)) { 4507 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GD, 4508 /*ForVTable=*/false); 4509 LT = getFunctionLinkage(GD); 4510 } else { 4511 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), 4512 llvm::PointerType::getUnqual(DeclTy), 4513 /*D=*/nullptr); 4514 LT = getLLVMLinkageVarDefinition(cast<VarDecl>(GD.getDecl()), 4515 D->getType().isConstQualified()); 4516 } 4517 4518 // Create the new alias itself, but don't set a name yet. 4519 auto *GA = 4520 llvm::GlobalAlias::create(DeclTy, 0, LT, "", Aliasee, &getModule()); 4521 4522 if (Entry) { 4523 if (GA->getAliasee() == Entry) { 4524 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0; 4525 return; 4526 } 4527 4528 assert(Entry->isDeclaration()); 4529 4530 // If there is a declaration in the module, then we had an extern followed 4531 // by the alias, as in: 4532 // extern int test6(); 4533 // ... 4534 // int test6() __attribute__((alias("test7"))); 4535 // 4536 // Remove it and replace uses of it with the alias. 4537 GA->takeName(Entry); 4538 4539 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GA, 4540 Entry->getType())); 4541 Entry->eraseFromParent(); 4542 } else { 4543 GA->setName(MangledName); 4544 } 4545 4546 // Set attributes which are particular to an alias; this is a 4547 // specialization of the attributes which may be set on a global 4548 // variable/function. 4549 if (D->hasAttr<WeakAttr>() || D->hasAttr<WeakRefAttr>() || 4550 D->isWeakImported()) { 4551 GA->setLinkage(llvm::Function::WeakAnyLinkage); 4552 } 4553 4554 if (const auto *VD = dyn_cast<VarDecl>(D)) 4555 if (VD->getTLSKind()) 4556 setTLSMode(GA, *VD); 4557 4558 SetCommonAttributes(GD, GA); 4559 } 4560 4561 void CodeGenModule::emitIFuncDefinition(GlobalDecl GD) { 4562 const auto *D = cast<ValueDecl>(GD.getDecl()); 4563 const IFuncAttr *IFA = D->getAttr<IFuncAttr>(); 4564 assert(IFA && "Not an ifunc?"); 4565 4566 StringRef MangledName = getMangledName(GD); 4567 4568 if (IFA->getResolver() == MangledName) { 4569 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1; 4570 return; 4571 } 4572 4573 // Report an error if some definition overrides ifunc. 4574 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 4575 if (Entry && !Entry->isDeclaration()) { 4576 GlobalDecl OtherGD; 4577 if (lookupRepresentativeDecl(MangledName, OtherGD) && 4578 DiagnosedConflictingDefinitions.insert(GD).second) { 4579 Diags.Report(D->getLocation(), diag::err_duplicate_mangled_name) 4580 << MangledName; 4581 Diags.Report(OtherGD.getDecl()->getLocation(), 4582 diag::note_previous_definition); 4583 } 4584 return; 4585 } 4586 4587 Aliases.push_back(GD); 4588 4589 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 4590 llvm::Constant *Resolver = 4591 GetOrCreateLLVMFunction(IFA->getResolver(), DeclTy, GD, 4592 /*ForVTable=*/false); 4593 llvm::GlobalIFunc *GIF = 4594 llvm::GlobalIFunc::create(DeclTy, 0, llvm::Function::ExternalLinkage, 4595 "", Resolver, &getModule()); 4596 if (Entry) { 4597 if (GIF->getResolver() == Entry) { 4598 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1; 4599 return; 4600 } 4601 assert(Entry->isDeclaration()); 4602 4603 // If there is a declaration in the module, then we had an extern followed 4604 // by the ifunc, as in: 4605 // extern int test(); 4606 // ... 4607 // int test() __attribute__((ifunc("resolver"))); 4608 // 4609 // Remove it and replace uses of it with the ifunc. 4610 GIF->takeName(Entry); 4611 4612 Entry->replaceAllUsesWith(llvm::ConstantExpr::getBitCast(GIF, 4613 Entry->getType())); 4614 Entry->eraseFromParent(); 4615 } else 4616 GIF->setName(MangledName); 4617 4618 SetCommonAttributes(GD, GIF); 4619 } 4620 4621 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID, 4622 ArrayRef<llvm::Type*> Tys) { 4623 return llvm::Intrinsic::getDeclaration(&getModule(), (llvm::Intrinsic::ID)IID, 4624 Tys); 4625 } 4626 4627 static llvm::StringMapEntry<llvm::GlobalVariable *> & 4628 GetConstantCFStringEntry(llvm::StringMap<llvm::GlobalVariable *> &Map, 4629 const StringLiteral *Literal, bool TargetIsLSB, 4630 bool &IsUTF16, unsigned &StringLength) { 4631 StringRef String = Literal->getString(); 4632 unsigned NumBytes = String.size(); 4633 4634 // Check for simple case. 4635 if (!Literal->containsNonAsciiOrNull()) { 4636 StringLength = NumBytes; 4637 return *Map.insert(std::make_pair(String, nullptr)).first; 4638 } 4639 4640 // Otherwise, convert the UTF8 literals into a string of shorts. 4641 IsUTF16 = true; 4642 4643 SmallVector<llvm::UTF16, 128> ToBuf(NumBytes + 1); // +1 for ending nulls. 4644 const llvm::UTF8 *FromPtr = (const llvm::UTF8 *)String.data(); 4645 llvm::UTF16 *ToPtr = &ToBuf[0]; 4646 4647 (void)llvm::ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, &ToPtr, 4648 ToPtr + NumBytes, llvm::strictConversion); 4649 4650 // ConvertUTF8toUTF16 returns the length in ToPtr. 4651 StringLength = ToPtr - &ToBuf[0]; 4652 4653 // Add an explicit null. 4654 *ToPtr = 0; 4655 return *Map.insert(std::make_pair( 4656 StringRef(reinterpret_cast<const char *>(ToBuf.data()), 4657 (StringLength + 1) * 2), 4658 nullptr)).first; 4659 } 4660 4661 ConstantAddress 4662 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { 4663 unsigned StringLength = 0; 4664 bool isUTF16 = false; 4665 llvm::StringMapEntry<llvm::GlobalVariable *> &Entry = 4666 GetConstantCFStringEntry(CFConstantStringMap, Literal, 4667 getDataLayout().isLittleEndian(), isUTF16, 4668 StringLength); 4669 4670 if (auto *C = Entry.second) 4671 return ConstantAddress(C, CharUnits::fromQuantity(C->getAlignment())); 4672 4673 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty); 4674 llvm::Constant *Zeros[] = { Zero, Zero }; 4675 4676 const ASTContext &Context = getContext(); 4677 const llvm::Triple &Triple = getTriple(); 4678 4679 const auto CFRuntime = getLangOpts().CFRuntime; 4680 const bool IsSwiftABI = 4681 static_cast<unsigned>(CFRuntime) >= 4682 static_cast<unsigned>(LangOptions::CoreFoundationABI::Swift); 4683 const bool IsSwift4_1 = CFRuntime == LangOptions::CoreFoundationABI::Swift4_1; 4684 4685 // If we don't already have it, get __CFConstantStringClassReference. 4686 if (!CFConstantStringClassRef) { 4687 const char *CFConstantStringClassName = "__CFConstantStringClassReference"; 4688 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); 4689 Ty = llvm::ArrayType::get(Ty, 0); 4690 4691 switch (CFRuntime) { 4692 default: break; 4693 case LangOptions::CoreFoundationABI::Swift: LLVM_FALLTHROUGH; 4694 case LangOptions::CoreFoundationABI::Swift5_0: 4695 CFConstantStringClassName = 4696 Triple.isOSDarwin() ? "$s15SwiftFoundation19_NSCFConstantStringCN" 4697 : "$s10Foundation19_NSCFConstantStringCN"; 4698 Ty = IntPtrTy; 4699 break; 4700 case LangOptions::CoreFoundationABI::Swift4_2: 4701 CFConstantStringClassName = 4702 Triple.isOSDarwin() ? "$S15SwiftFoundation19_NSCFConstantStringCN" 4703 : "$S10Foundation19_NSCFConstantStringCN"; 4704 Ty = IntPtrTy; 4705 break; 4706 case LangOptions::CoreFoundationABI::Swift4_1: 4707 CFConstantStringClassName = 4708 Triple.isOSDarwin() ? "__T015SwiftFoundation19_NSCFConstantStringCN" 4709 : "__T010Foundation19_NSCFConstantStringCN"; 4710 Ty = IntPtrTy; 4711 break; 4712 } 4713 4714 llvm::Constant *C = CreateRuntimeVariable(Ty, CFConstantStringClassName); 4715 4716 if (Triple.isOSBinFormatELF() || Triple.isOSBinFormatCOFF()) { 4717 llvm::GlobalValue *GV = nullptr; 4718 4719 if ((GV = dyn_cast<llvm::GlobalValue>(C))) { 4720 IdentifierInfo &II = Context.Idents.get(GV->getName()); 4721 TranslationUnitDecl *TUDecl = Context.getTranslationUnitDecl(); 4722 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); 4723 4724 const VarDecl *VD = nullptr; 4725 for (const auto &Result : DC->lookup(&II)) 4726 if ((VD = dyn_cast<VarDecl>(Result))) 4727 break; 4728 4729 if (Triple.isOSBinFormatELF()) { 4730 if (!VD) 4731 GV->setLinkage(llvm::GlobalValue::ExternalLinkage); 4732 } else { 4733 GV->setLinkage(llvm::GlobalValue::ExternalLinkage); 4734 if (!VD || !VD->hasAttr<DLLExportAttr>()) 4735 GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass); 4736 else 4737 GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass); 4738 } 4739 4740 setDSOLocal(GV); 4741 } 4742 } 4743 4744 // Decay array -> ptr 4745 CFConstantStringClassRef = 4746 IsSwiftABI ? llvm::ConstantExpr::getPtrToInt(C, Ty) 4747 : llvm::ConstantExpr::getGetElementPtr(Ty, C, Zeros); 4748 } 4749 4750 QualType CFTy = Context.getCFConstantStringType(); 4751 4752 auto *STy = cast<llvm::StructType>(getTypes().ConvertType(CFTy)); 4753 4754 ConstantInitBuilder Builder(*this); 4755 auto Fields = Builder.beginStruct(STy); 4756 4757 // Class pointer. 4758 Fields.add(cast<llvm::ConstantExpr>(CFConstantStringClassRef)); 4759 4760 // Flags. 4761 if (IsSwiftABI) { 4762 Fields.addInt(IntPtrTy, IsSwift4_1 ? 0x05 : 0x01); 4763 Fields.addInt(Int64Ty, isUTF16 ? 0x07d0 : 0x07c8); 4764 } else { 4765 Fields.addInt(IntTy, isUTF16 ? 0x07d0 : 0x07C8); 4766 } 4767 4768 // String pointer. 4769 llvm::Constant *C = nullptr; 4770 if (isUTF16) { 4771 auto Arr = llvm::makeArrayRef( 4772 reinterpret_cast<uint16_t *>(const_cast<char *>(Entry.first().data())), 4773 Entry.first().size() / 2); 4774 C = llvm::ConstantDataArray::get(VMContext, Arr); 4775 } else { 4776 C = llvm::ConstantDataArray::getString(VMContext, Entry.first()); 4777 } 4778 4779 // Note: -fwritable-strings doesn't make the backing store strings of 4780 // CFStrings writable. (See <rdar://problem/10657500>) 4781 auto *GV = 4782 new llvm::GlobalVariable(getModule(), C->getType(), /*isConstant=*/true, 4783 llvm::GlobalValue::PrivateLinkage, C, ".str"); 4784 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 4785 // Don't enforce the target's minimum global alignment, since the only use 4786 // of the string is via this class initializer. 4787 CharUnits Align = isUTF16 ? Context.getTypeAlignInChars(Context.ShortTy) 4788 : Context.getTypeAlignInChars(Context.CharTy); 4789 GV->setAlignment(Align.getAsAlign()); 4790 4791 // FIXME: We set the section explicitly to avoid a bug in ld64 224.1. 4792 // Without it LLVM can merge the string with a non unnamed_addr one during 4793 // LTO. Doing that changes the section it ends in, which surprises ld64. 4794 if (Triple.isOSBinFormatMachO()) 4795 GV->setSection(isUTF16 ? "__TEXT,__ustring" 4796 : "__TEXT,__cstring,cstring_literals"); 4797 // Make sure the literal ends up in .rodata to allow for safe ICF and for 4798 // the static linker to adjust permissions to read-only later on. 4799 else if (Triple.isOSBinFormatELF()) 4800 GV->setSection(".rodata"); 4801 4802 // String. 4803 llvm::Constant *Str = 4804 llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV, Zeros); 4805 4806 if (isUTF16) 4807 // Cast the UTF16 string to the correct type. 4808 Str = llvm::ConstantExpr::getBitCast(Str, Int8PtrTy); 4809 Fields.add(Str); 4810 4811 // String length. 4812 llvm::IntegerType *LengthTy = 4813 llvm::IntegerType::get(getModule().getContext(), 4814 Context.getTargetInfo().getLongWidth()); 4815 if (IsSwiftABI) { 4816 if (CFRuntime == LangOptions::CoreFoundationABI::Swift4_1 || 4817 CFRuntime == LangOptions::CoreFoundationABI::Swift4_2) 4818 LengthTy = Int32Ty; 4819 else 4820 LengthTy = IntPtrTy; 4821 } 4822 Fields.addInt(LengthTy, StringLength); 4823 4824 // Swift ABI requires 8-byte alignment to ensure that the _Atomic(uint64_t) is 4825 // properly aligned on 32-bit platforms. 4826 CharUnits Alignment = 4827 IsSwiftABI ? Context.toCharUnitsFromBits(64) : getPointerAlign(); 4828 4829 // The struct. 4830 GV = Fields.finishAndCreateGlobal("_unnamed_cfstring_", Alignment, 4831 /*isConstant=*/false, 4832 llvm::GlobalVariable::PrivateLinkage); 4833 GV->addAttribute("objc_arc_inert"); 4834 switch (Triple.getObjectFormat()) { 4835 case llvm::Triple::UnknownObjectFormat: 4836 llvm_unreachable("unknown file format"); 4837 case llvm::Triple::XCOFF: 4838 llvm_unreachable("XCOFF is not yet implemented"); 4839 case llvm::Triple::COFF: 4840 case llvm::Triple::ELF: 4841 case llvm::Triple::Wasm: 4842 GV->setSection("cfstring"); 4843 break; 4844 case llvm::Triple::MachO: 4845 GV->setSection("__DATA,__cfstring"); 4846 break; 4847 } 4848 Entry.second = GV; 4849 4850 return ConstantAddress(GV, Alignment); 4851 } 4852 4853 bool CodeGenModule::getExpressionLocationsEnabled() const { 4854 return !CodeGenOpts.EmitCodeView || CodeGenOpts.DebugColumnInfo; 4855 } 4856 4857 QualType CodeGenModule::getObjCFastEnumerationStateType() { 4858 if (ObjCFastEnumerationStateType.isNull()) { 4859 RecordDecl *D = Context.buildImplicitRecord("__objcFastEnumerationState"); 4860 D->startDefinition(); 4861 4862 QualType FieldTypes[] = { 4863 Context.UnsignedLongTy, 4864 Context.getPointerType(Context.getObjCIdType()), 4865 Context.getPointerType(Context.UnsignedLongTy), 4866 Context.getConstantArrayType(Context.UnsignedLongTy, 4867 llvm::APInt(32, 5), nullptr, ArrayType::Normal, 0) 4868 }; 4869 4870 for (size_t i = 0; i < 4; ++i) { 4871 FieldDecl *Field = FieldDecl::Create(Context, 4872 D, 4873 SourceLocation(), 4874 SourceLocation(), nullptr, 4875 FieldTypes[i], /*TInfo=*/nullptr, 4876 /*BitWidth=*/nullptr, 4877 /*Mutable=*/false, 4878 ICIS_NoInit); 4879 Field->setAccess(AS_public); 4880 D->addDecl(Field); 4881 } 4882 4883 D->completeDefinition(); 4884 ObjCFastEnumerationStateType = Context.getTagDeclType(D); 4885 } 4886 4887 return ObjCFastEnumerationStateType; 4888 } 4889 4890 llvm::Constant * 4891 CodeGenModule::GetConstantArrayFromStringLiteral(const StringLiteral *E) { 4892 assert(!E->getType()->isPointerType() && "Strings are always arrays"); 4893 4894 // Don't emit it as the address of the string, emit the string data itself 4895 // as an inline array. 4896 if (E->getCharByteWidth() == 1) { 4897 SmallString<64> Str(E->getString()); 4898 4899 // Resize the string to the right size, which is indicated by its type. 4900 const ConstantArrayType *CAT = Context.getAsConstantArrayType(E->getType()); 4901 Str.resize(CAT->getSize().getZExtValue()); 4902 return llvm::ConstantDataArray::getString(VMContext, Str, false); 4903 } 4904 4905 auto *AType = cast<llvm::ArrayType>(getTypes().ConvertType(E->getType())); 4906 llvm::Type *ElemTy = AType->getElementType(); 4907 unsigned NumElements = AType->getNumElements(); 4908 4909 // Wide strings have either 2-byte or 4-byte elements. 4910 if (ElemTy->getPrimitiveSizeInBits() == 16) { 4911 SmallVector<uint16_t, 32> Elements; 4912 Elements.reserve(NumElements); 4913 4914 for(unsigned i = 0, e = E->getLength(); i != e; ++i) 4915 Elements.push_back(E->getCodeUnit(i)); 4916 Elements.resize(NumElements); 4917 return llvm::ConstantDataArray::get(VMContext, Elements); 4918 } 4919 4920 assert(ElemTy->getPrimitiveSizeInBits() == 32); 4921 SmallVector<uint32_t, 32> Elements; 4922 Elements.reserve(NumElements); 4923 4924 for(unsigned i = 0, e = E->getLength(); i != e; ++i) 4925 Elements.push_back(E->getCodeUnit(i)); 4926 Elements.resize(NumElements); 4927 return llvm::ConstantDataArray::get(VMContext, Elements); 4928 } 4929 4930 static llvm::GlobalVariable * 4931 GenerateStringLiteral(llvm::Constant *C, llvm::GlobalValue::LinkageTypes LT, 4932 CodeGenModule &CGM, StringRef GlobalName, 4933 CharUnits Alignment) { 4934 unsigned AddrSpace = CGM.getContext().getTargetAddressSpace( 4935 CGM.getStringLiteralAddressSpace()); 4936 4937 llvm::Module &M = CGM.getModule(); 4938 // Create a global variable for this string 4939 auto *GV = new llvm::GlobalVariable( 4940 M, C->getType(), !CGM.getLangOpts().WritableStrings, LT, C, GlobalName, 4941 nullptr, llvm::GlobalVariable::NotThreadLocal, AddrSpace); 4942 GV->setAlignment(Alignment.getAsAlign()); 4943 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 4944 if (GV->isWeakForLinker()) { 4945 assert(CGM.supportsCOMDAT() && "Only COFF uses weak string literals"); 4946 GV->setComdat(M.getOrInsertComdat(GV->getName())); 4947 } 4948 CGM.setDSOLocal(GV); 4949 4950 return GV; 4951 } 4952 4953 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a 4954 /// constant array for the given string literal. 4955 ConstantAddress 4956 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S, 4957 StringRef Name) { 4958 CharUnits Alignment = getContext().getAlignOfGlobalVarInChars(S->getType()); 4959 4960 llvm::Constant *C = GetConstantArrayFromStringLiteral(S); 4961 llvm::GlobalVariable **Entry = nullptr; 4962 if (!LangOpts.WritableStrings) { 4963 Entry = &ConstantStringMap[C]; 4964 if (auto GV = *Entry) { 4965 if (Alignment.getQuantity() > GV->getAlignment()) 4966 GV->setAlignment(Alignment.getAsAlign()); 4967 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 4968 Alignment); 4969 } 4970 } 4971 4972 SmallString<256> MangledNameBuffer; 4973 StringRef GlobalVariableName; 4974 llvm::GlobalValue::LinkageTypes LT; 4975 4976 // Mangle the string literal if that's how the ABI merges duplicate strings. 4977 // Don't do it if they are writable, since we don't want writes in one TU to 4978 // affect strings in another. 4979 if (getCXXABI().getMangleContext().shouldMangleStringLiteral(S) && 4980 !LangOpts.WritableStrings) { 4981 llvm::raw_svector_ostream Out(MangledNameBuffer); 4982 getCXXABI().getMangleContext().mangleStringLiteral(S, Out); 4983 LT = llvm::GlobalValue::LinkOnceODRLinkage; 4984 GlobalVariableName = MangledNameBuffer; 4985 } else { 4986 LT = llvm::GlobalValue::PrivateLinkage; 4987 GlobalVariableName = Name; 4988 } 4989 4990 auto GV = GenerateStringLiteral(C, LT, *this, GlobalVariableName, Alignment); 4991 if (Entry) 4992 *Entry = GV; 4993 4994 SanitizerMD->reportGlobalToASan(GV, S->getStrTokenLoc(0), "<string literal>", 4995 QualType()); 4996 4997 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 4998 Alignment); 4999 } 5000 5001 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant 5002 /// array for the given ObjCEncodeExpr node. 5003 ConstantAddress 5004 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) { 5005 std::string Str; 5006 getContext().getObjCEncodingForType(E->getEncodedType(), Str); 5007 5008 return GetAddrOfConstantCString(Str); 5009 } 5010 5011 /// GetAddrOfConstantCString - Returns a pointer to a character array containing 5012 /// the literal and a terminating '\0' character. 5013 /// The result has pointer to array type. 5014 ConstantAddress CodeGenModule::GetAddrOfConstantCString( 5015 const std::string &Str, const char *GlobalName) { 5016 StringRef StrWithNull(Str.c_str(), Str.size() + 1); 5017 CharUnits Alignment = 5018 getContext().getAlignOfGlobalVarInChars(getContext().CharTy); 5019 5020 llvm::Constant *C = 5021 llvm::ConstantDataArray::getString(getLLVMContext(), StrWithNull, false); 5022 5023 // Don't share any string literals if strings aren't constant. 5024 llvm::GlobalVariable **Entry = nullptr; 5025 if (!LangOpts.WritableStrings) { 5026 Entry = &ConstantStringMap[C]; 5027 if (auto GV = *Entry) { 5028 if (Alignment.getQuantity() > GV->getAlignment()) 5029 GV->setAlignment(Alignment.getAsAlign()); 5030 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 5031 Alignment); 5032 } 5033 } 5034 5035 // Get the default prefix if a name wasn't specified. 5036 if (!GlobalName) 5037 GlobalName = ".str"; 5038 // Create a global variable for this. 5039 auto GV = GenerateStringLiteral(C, llvm::GlobalValue::PrivateLinkage, *this, 5040 GlobalName, Alignment); 5041 if (Entry) 5042 *Entry = GV; 5043 5044 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 5045 Alignment); 5046 } 5047 5048 ConstantAddress CodeGenModule::GetAddrOfGlobalTemporary( 5049 const MaterializeTemporaryExpr *E, const Expr *Init) { 5050 assert((E->getStorageDuration() == SD_Static || 5051 E->getStorageDuration() == SD_Thread) && "not a global temporary"); 5052 const auto *VD = cast<VarDecl>(E->getExtendingDecl()); 5053 5054 // If we're not materializing a subobject of the temporary, keep the 5055 // cv-qualifiers from the type of the MaterializeTemporaryExpr. 5056 QualType MaterializedType = Init->getType(); 5057 if (Init == E->getSubExpr()) 5058 MaterializedType = E->getType(); 5059 5060 CharUnits Align = getContext().getTypeAlignInChars(MaterializedType); 5061 5062 if (llvm::Constant *Slot = MaterializedGlobalTemporaryMap[E]) 5063 return ConstantAddress(Slot, Align); 5064 5065 // FIXME: If an externally-visible declaration extends multiple temporaries, 5066 // we need to give each temporary the same name in every translation unit (and 5067 // we also need to make the temporaries externally-visible). 5068 SmallString<256> Name; 5069 llvm::raw_svector_ostream Out(Name); 5070 getCXXABI().getMangleContext().mangleReferenceTemporary( 5071 VD, E->getManglingNumber(), Out); 5072 5073 APValue *Value = nullptr; 5074 if (E->getStorageDuration() == SD_Static && VD && VD->evaluateValue()) { 5075 // If the initializer of the extending declaration is a constant 5076 // initializer, we should have a cached constant initializer for this 5077 // temporary. Note that this might have a different value from the value 5078 // computed by evaluating the initializer if the surrounding constant 5079 // expression modifies the temporary. 5080 Value = E->getOrCreateValue(false); 5081 } 5082 5083 // Try evaluating it now, it might have a constant initializer. 5084 Expr::EvalResult EvalResult; 5085 if (!Value && Init->EvaluateAsRValue(EvalResult, getContext()) && 5086 !EvalResult.hasSideEffects()) 5087 Value = &EvalResult.Val; 5088 5089 LangAS AddrSpace = 5090 VD ? GetGlobalVarAddressSpace(VD) : MaterializedType.getAddressSpace(); 5091 5092 Optional<ConstantEmitter> emitter; 5093 llvm::Constant *InitialValue = nullptr; 5094 bool Constant = false; 5095 llvm::Type *Type; 5096 if (Value) { 5097 // The temporary has a constant initializer, use it. 5098 emitter.emplace(*this); 5099 InitialValue = emitter->emitForInitializer(*Value, AddrSpace, 5100 MaterializedType); 5101 Constant = isTypeConstant(MaterializedType, /*ExcludeCtor*/Value); 5102 Type = InitialValue->getType(); 5103 } else { 5104 // No initializer, the initialization will be provided when we 5105 // initialize the declaration which performed lifetime extension. 5106 Type = getTypes().ConvertTypeForMem(MaterializedType); 5107 } 5108 5109 // Create a global variable for this lifetime-extended temporary. 5110 llvm::GlobalValue::LinkageTypes Linkage = 5111 getLLVMLinkageVarDefinition(VD, Constant); 5112 if (Linkage == llvm::GlobalVariable::ExternalLinkage) { 5113 const VarDecl *InitVD; 5114 if (VD->isStaticDataMember() && VD->getAnyInitializer(InitVD) && 5115 isa<CXXRecordDecl>(InitVD->getLexicalDeclContext())) { 5116 // Temporaries defined inside a class get linkonce_odr linkage because the 5117 // class can be defined in multiple translation units. 5118 Linkage = llvm::GlobalVariable::LinkOnceODRLinkage; 5119 } else { 5120 // There is no need for this temporary to have external linkage if the 5121 // VarDecl has external linkage. 5122 Linkage = llvm::GlobalVariable::InternalLinkage; 5123 } 5124 } 5125 auto TargetAS = getContext().getTargetAddressSpace(AddrSpace); 5126 auto *GV = new llvm::GlobalVariable( 5127 getModule(), Type, Constant, Linkage, InitialValue, Name.c_str(), 5128 /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal, TargetAS); 5129 if (emitter) emitter->finalize(GV); 5130 setGVProperties(GV, VD); 5131 GV->setAlignment(Align.getAsAlign()); 5132 if (supportsCOMDAT() && GV->isWeakForLinker()) 5133 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 5134 if (VD->getTLSKind()) 5135 setTLSMode(GV, *VD); 5136 llvm::Constant *CV = GV; 5137 if (AddrSpace != LangAS::Default) 5138 CV = getTargetCodeGenInfo().performAddrSpaceCast( 5139 *this, GV, AddrSpace, LangAS::Default, 5140 Type->getPointerTo( 5141 getContext().getTargetAddressSpace(LangAS::Default))); 5142 MaterializedGlobalTemporaryMap[E] = CV; 5143 return ConstantAddress(CV, Align); 5144 } 5145 5146 /// EmitObjCPropertyImplementations - Emit information for synthesized 5147 /// properties for an implementation. 5148 void CodeGenModule::EmitObjCPropertyImplementations(const 5149 ObjCImplementationDecl *D) { 5150 for (const auto *PID : D->property_impls()) { 5151 // Dynamic is just for type-checking. 5152 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) { 5153 ObjCPropertyDecl *PD = PID->getPropertyDecl(); 5154 5155 // Determine which methods need to be implemented, some may have 5156 // been overridden. Note that ::isPropertyAccessor is not the method 5157 // we want, that just indicates if the decl came from a 5158 // property. What we want to know is if the method is defined in 5159 // this implementation. 5160 auto *Getter = PID->getGetterMethodDecl(); 5161 if (!Getter || Getter->isSynthesizedAccessorStub()) 5162 CodeGenFunction(*this).GenerateObjCGetter( 5163 const_cast<ObjCImplementationDecl *>(D), PID); 5164 auto *Setter = PID->getSetterMethodDecl(); 5165 if (!PD->isReadOnly() && (!Setter || Setter->isSynthesizedAccessorStub())) 5166 CodeGenFunction(*this).GenerateObjCSetter( 5167 const_cast<ObjCImplementationDecl *>(D), PID); 5168 } 5169 } 5170 } 5171 5172 static bool needsDestructMethod(ObjCImplementationDecl *impl) { 5173 const ObjCInterfaceDecl *iface = impl->getClassInterface(); 5174 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin(); 5175 ivar; ivar = ivar->getNextIvar()) 5176 if (ivar->getType().isDestructedType()) 5177 return true; 5178 5179 return false; 5180 } 5181 5182 static bool AllTrivialInitializers(CodeGenModule &CGM, 5183 ObjCImplementationDecl *D) { 5184 CodeGenFunction CGF(CGM); 5185 for (ObjCImplementationDecl::init_iterator B = D->init_begin(), 5186 E = D->init_end(); B != E; ++B) { 5187 CXXCtorInitializer *CtorInitExp = *B; 5188 Expr *Init = CtorInitExp->getInit(); 5189 if (!CGF.isTrivialInitializer(Init)) 5190 return false; 5191 } 5192 return true; 5193 } 5194 5195 /// EmitObjCIvarInitializations - Emit information for ivar initialization 5196 /// for an implementation. 5197 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) { 5198 // We might need a .cxx_destruct even if we don't have any ivar initializers. 5199 if (needsDestructMethod(D)) { 5200 IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct"); 5201 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 5202 ObjCMethodDecl *DTORMethod = ObjCMethodDecl::Create( 5203 getContext(), D->getLocation(), D->getLocation(), cxxSelector, 5204 getContext().VoidTy, nullptr, D, 5205 /*isInstance=*/true, /*isVariadic=*/false, 5206 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false, 5207 /*isImplicitlyDeclared=*/true, 5208 /*isDefined=*/false, ObjCMethodDecl::Required); 5209 D->addInstanceMethod(DTORMethod); 5210 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false); 5211 D->setHasDestructors(true); 5212 } 5213 5214 // If the implementation doesn't have any ivar initializers, we don't need 5215 // a .cxx_construct. 5216 if (D->getNumIvarInitializers() == 0 || 5217 AllTrivialInitializers(*this, D)) 5218 return; 5219 5220 IdentifierInfo *II = &getContext().Idents.get(".cxx_construct"); 5221 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 5222 // The constructor returns 'self'. 5223 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create( 5224 getContext(), D->getLocation(), D->getLocation(), cxxSelector, 5225 getContext().getObjCIdType(), nullptr, D, /*isInstance=*/true, 5226 /*isVariadic=*/false, 5227 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false, 5228 /*isImplicitlyDeclared=*/true, 5229 /*isDefined=*/false, ObjCMethodDecl::Required); 5230 D->addInstanceMethod(CTORMethod); 5231 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true); 5232 D->setHasNonZeroConstructors(true); 5233 } 5234 5235 // EmitLinkageSpec - Emit all declarations in a linkage spec. 5236 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) { 5237 if (LSD->getLanguage() != LinkageSpecDecl::lang_c && 5238 LSD->getLanguage() != LinkageSpecDecl::lang_cxx) { 5239 ErrorUnsupported(LSD, "linkage spec"); 5240 return; 5241 } 5242 5243 EmitDeclContext(LSD); 5244 } 5245 5246 void CodeGenModule::EmitDeclContext(const DeclContext *DC) { 5247 for (auto *I : DC->decls()) { 5248 // Unlike other DeclContexts, the contents of an ObjCImplDecl at TU scope 5249 // are themselves considered "top-level", so EmitTopLevelDecl on an 5250 // ObjCImplDecl does not recursively visit them. We need to do that in 5251 // case they're nested inside another construct (LinkageSpecDecl / 5252 // ExportDecl) that does stop them from being considered "top-level". 5253 if (auto *OID = dyn_cast<ObjCImplDecl>(I)) { 5254 for (auto *M : OID->methods()) 5255 EmitTopLevelDecl(M); 5256 } 5257 5258 EmitTopLevelDecl(I); 5259 } 5260 } 5261 5262 /// EmitTopLevelDecl - Emit code for a single top level declaration. 5263 void CodeGenModule::EmitTopLevelDecl(Decl *D) { 5264 // Ignore dependent declarations. 5265 if (D->isTemplated()) 5266 return; 5267 5268 switch (D->getKind()) { 5269 case Decl::CXXConversion: 5270 case Decl::CXXMethod: 5271 case Decl::Function: 5272 EmitGlobal(cast<FunctionDecl>(D)); 5273 // Always provide some coverage mapping 5274 // even for the functions that aren't emitted. 5275 AddDeferredUnusedCoverageMapping(D); 5276 break; 5277 5278 case Decl::CXXDeductionGuide: 5279 // Function-like, but does not result in code emission. 5280 break; 5281 5282 case Decl::Var: 5283 case Decl::Decomposition: 5284 case Decl::VarTemplateSpecialization: 5285 EmitGlobal(cast<VarDecl>(D)); 5286 if (auto *DD = dyn_cast<DecompositionDecl>(D)) 5287 for (auto *B : DD->bindings()) 5288 if (auto *HD = B->getHoldingVar()) 5289 EmitGlobal(HD); 5290 break; 5291 5292 // Indirect fields from global anonymous structs and unions can be 5293 // ignored; only the actual variable requires IR gen support. 5294 case Decl::IndirectField: 5295 break; 5296 5297 // C++ Decls 5298 case Decl::Namespace: 5299 EmitDeclContext(cast<NamespaceDecl>(D)); 5300 break; 5301 case Decl::ClassTemplateSpecialization: { 5302 const auto *Spec = cast<ClassTemplateSpecializationDecl>(D); 5303 if (DebugInfo && 5304 Spec->getSpecializationKind() == TSK_ExplicitInstantiationDefinition && 5305 Spec->hasDefinition()) 5306 DebugInfo->completeTemplateDefinition(*Spec); 5307 } LLVM_FALLTHROUGH; 5308 case Decl::CXXRecord: 5309 if (DebugInfo) { 5310 if (auto *ES = D->getASTContext().getExternalSource()) 5311 if (ES->hasExternalDefinitions(D) == ExternalASTSource::EK_Never) 5312 DebugInfo->completeUnusedClass(cast<CXXRecordDecl>(*D)); 5313 } 5314 // Emit any static data members, they may be definitions. 5315 for (auto *I : cast<CXXRecordDecl>(D)->decls()) 5316 if (isa<VarDecl>(I) || isa<CXXRecordDecl>(I)) 5317 EmitTopLevelDecl(I); 5318 break; 5319 // No code generation needed. 5320 case Decl::UsingShadow: 5321 case Decl::ClassTemplate: 5322 case Decl::VarTemplate: 5323 case Decl::Concept: 5324 case Decl::VarTemplatePartialSpecialization: 5325 case Decl::FunctionTemplate: 5326 case Decl::TypeAliasTemplate: 5327 case Decl::Block: 5328 case Decl::Empty: 5329 case Decl::Binding: 5330 break; 5331 case Decl::Using: // using X; [C++] 5332 if (CGDebugInfo *DI = getModuleDebugInfo()) 5333 DI->EmitUsingDecl(cast<UsingDecl>(*D)); 5334 return; 5335 case Decl::NamespaceAlias: 5336 if (CGDebugInfo *DI = getModuleDebugInfo()) 5337 DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(*D)); 5338 return; 5339 case Decl::UsingDirective: // using namespace X; [C++] 5340 if (CGDebugInfo *DI = getModuleDebugInfo()) 5341 DI->EmitUsingDirective(cast<UsingDirectiveDecl>(*D)); 5342 return; 5343 case Decl::CXXConstructor: 5344 getCXXABI().EmitCXXConstructors(cast<CXXConstructorDecl>(D)); 5345 break; 5346 case Decl::CXXDestructor: 5347 getCXXABI().EmitCXXDestructors(cast<CXXDestructorDecl>(D)); 5348 break; 5349 5350 case Decl::StaticAssert: 5351 // Nothing to do. 5352 break; 5353 5354 // Objective-C Decls 5355 5356 // Forward declarations, no (immediate) code generation. 5357 case Decl::ObjCInterface: 5358 case Decl::ObjCCategory: 5359 break; 5360 5361 case Decl::ObjCProtocol: { 5362 auto *Proto = cast<ObjCProtocolDecl>(D); 5363 if (Proto->isThisDeclarationADefinition()) 5364 ObjCRuntime->GenerateProtocol(Proto); 5365 break; 5366 } 5367 5368 case Decl::ObjCCategoryImpl: 5369 // Categories have properties but don't support synthesize so we 5370 // can ignore them here. 5371 ObjCRuntime->GenerateCategory(cast<ObjCCategoryImplDecl>(D)); 5372 break; 5373 5374 case Decl::ObjCImplementation: { 5375 auto *OMD = cast<ObjCImplementationDecl>(D); 5376 EmitObjCPropertyImplementations(OMD); 5377 EmitObjCIvarInitializations(OMD); 5378 ObjCRuntime->GenerateClass(OMD); 5379 // Emit global variable debug information. 5380 if (CGDebugInfo *DI = getModuleDebugInfo()) 5381 if (getCodeGenOpts().hasReducedDebugInfo()) 5382 DI->getOrCreateInterfaceType(getContext().getObjCInterfaceType( 5383 OMD->getClassInterface()), OMD->getLocation()); 5384 break; 5385 } 5386 case Decl::ObjCMethod: { 5387 auto *OMD = cast<ObjCMethodDecl>(D); 5388 // If this is not a prototype, emit the body. 5389 if (OMD->getBody()) 5390 CodeGenFunction(*this).GenerateObjCMethod(OMD); 5391 break; 5392 } 5393 case Decl::ObjCCompatibleAlias: 5394 ObjCRuntime->RegisterAlias(cast<ObjCCompatibleAliasDecl>(D)); 5395 break; 5396 5397 case Decl::PragmaComment: { 5398 const auto *PCD = cast<PragmaCommentDecl>(D); 5399 switch (PCD->getCommentKind()) { 5400 case PCK_Unknown: 5401 llvm_unreachable("unexpected pragma comment kind"); 5402 case PCK_Linker: 5403 AppendLinkerOptions(PCD->getArg()); 5404 break; 5405 case PCK_Lib: 5406 AddDependentLib(PCD->getArg()); 5407 break; 5408 case PCK_Compiler: 5409 case PCK_ExeStr: 5410 case PCK_User: 5411 break; // We ignore all of these. 5412 } 5413 break; 5414 } 5415 5416 case Decl::PragmaDetectMismatch: { 5417 const auto *PDMD = cast<PragmaDetectMismatchDecl>(D); 5418 AddDetectMismatch(PDMD->getName(), PDMD->getValue()); 5419 break; 5420 } 5421 5422 case Decl::LinkageSpec: 5423 EmitLinkageSpec(cast<LinkageSpecDecl>(D)); 5424 break; 5425 5426 case Decl::FileScopeAsm: { 5427 // File-scope asm is ignored during device-side CUDA compilation. 5428 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) 5429 break; 5430 // File-scope asm is ignored during device-side OpenMP compilation. 5431 if (LangOpts.OpenMPIsDevice) 5432 break; 5433 auto *AD = cast<FileScopeAsmDecl>(D); 5434 getModule().appendModuleInlineAsm(AD->getAsmString()->getString()); 5435 break; 5436 } 5437 5438 case Decl::Import: { 5439 auto *Import = cast<ImportDecl>(D); 5440 5441 // If we've already imported this module, we're done. 5442 if (!ImportedModules.insert(Import->getImportedModule())) 5443 break; 5444 5445 // Emit debug information for direct imports. 5446 if (!Import->getImportedOwningModule()) { 5447 if (CGDebugInfo *DI = getModuleDebugInfo()) 5448 DI->EmitImportDecl(*Import); 5449 } 5450 5451 // Find all of the submodules and emit the module initializers. 5452 llvm::SmallPtrSet<clang::Module *, 16> Visited; 5453 SmallVector<clang::Module *, 16> Stack; 5454 Visited.insert(Import->getImportedModule()); 5455 Stack.push_back(Import->getImportedModule()); 5456 5457 while (!Stack.empty()) { 5458 clang::Module *Mod = Stack.pop_back_val(); 5459 if (!EmittedModuleInitializers.insert(Mod).second) 5460 continue; 5461 5462 for (auto *D : Context.getModuleInitializers(Mod)) 5463 EmitTopLevelDecl(D); 5464 5465 // Visit the submodules of this module. 5466 for (clang::Module::submodule_iterator Sub = Mod->submodule_begin(), 5467 SubEnd = Mod->submodule_end(); 5468 Sub != SubEnd; ++Sub) { 5469 // Skip explicit children; they need to be explicitly imported to emit 5470 // the initializers. 5471 if ((*Sub)->IsExplicit) 5472 continue; 5473 5474 if (Visited.insert(*Sub).second) 5475 Stack.push_back(*Sub); 5476 } 5477 } 5478 break; 5479 } 5480 5481 case Decl::Export: 5482 EmitDeclContext(cast<ExportDecl>(D)); 5483 break; 5484 5485 case Decl::OMPThreadPrivate: 5486 EmitOMPThreadPrivateDecl(cast<OMPThreadPrivateDecl>(D)); 5487 break; 5488 5489 case Decl::OMPAllocate: 5490 break; 5491 5492 case Decl::OMPDeclareReduction: 5493 EmitOMPDeclareReduction(cast<OMPDeclareReductionDecl>(D)); 5494 break; 5495 5496 case Decl::OMPDeclareMapper: 5497 EmitOMPDeclareMapper(cast<OMPDeclareMapperDecl>(D)); 5498 break; 5499 5500 case Decl::OMPRequires: 5501 EmitOMPRequiresDecl(cast<OMPRequiresDecl>(D)); 5502 break; 5503 5504 default: 5505 // Make sure we handled everything we should, every other kind is a 5506 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind 5507 // function. Need to recode Decl::Kind to do that easily. 5508 assert(isa<TypeDecl>(D) && "Unsupported decl kind"); 5509 break; 5510 } 5511 } 5512 5513 void CodeGenModule::AddDeferredUnusedCoverageMapping(Decl *D) { 5514 // Do we need to generate coverage mapping? 5515 if (!CodeGenOpts.CoverageMapping) 5516 return; 5517 switch (D->getKind()) { 5518 case Decl::CXXConversion: 5519 case Decl::CXXMethod: 5520 case Decl::Function: 5521 case Decl::ObjCMethod: 5522 case Decl::CXXConstructor: 5523 case Decl::CXXDestructor: { 5524 if (!cast<FunctionDecl>(D)->doesThisDeclarationHaveABody()) 5525 return; 5526 SourceManager &SM = getContext().getSourceManager(); 5527 if (LimitedCoverage && SM.getMainFileID() != SM.getFileID(D->getBeginLoc())) 5528 return; 5529 auto I = DeferredEmptyCoverageMappingDecls.find(D); 5530 if (I == DeferredEmptyCoverageMappingDecls.end()) 5531 DeferredEmptyCoverageMappingDecls[D] = true; 5532 break; 5533 } 5534 default: 5535 break; 5536 }; 5537 } 5538 5539 void CodeGenModule::ClearUnusedCoverageMapping(const Decl *D) { 5540 // Do we need to generate coverage mapping? 5541 if (!CodeGenOpts.CoverageMapping) 5542 return; 5543 if (const auto *Fn = dyn_cast<FunctionDecl>(D)) { 5544 if (Fn->isTemplateInstantiation()) 5545 ClearUnusedCoverageMapping(Fn->getTemplateInstantiationPattern()); 5546 } 5547 auto I = DeferredEmptyCoverageMappingDecls.find(D); 5548 if (I == DeferredEmptyCoverageMappingDecls.end()) 5549 DeferredEmptyCoverageMappingDecls[D] = false; 5550 else 5551 I->second = false; 5552 } 5553 5554 void CodeGenModule::EmitDeferredUnusedCoverageMappings() { 5555 // We call takeVector() here to avoid use-after-free. 5556 // FIXME: DeferredEmptyCoverageMappingDecls is getting mutated because 5557 // we deserialize function bodies to emit coverage info for them, and that 5558 // deserializes more declarations. How should we handle that case? 5559 for (const auto &Entry : DeferredEmptyCoverageMappingDecls.takeVector()) { 5560 if (!Entry.second) 5561 continue; 5562 const Decl *D = Entry.first; 5563 switch (D->getKind()) { 5564 case Decl::CXXConversion: 5565 case Decl::CXXMethod: 5566 case Decl::Function: 5567 case Decl::ObjCMethod: { 5568 CodeGenPGO PGO(*this); 5569 GlobalDecl GD(cast<FunctionDecl>(D)); 5570 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 5571 getFunctionLinkage(GD)); 5572 break; 5573 } 5574 case Decl::CXXConstructor: { 5575 CodeGenPGO PGO(*this); 5576 GlobalDecl GD(cast<CXXConstructorDecl>(D), Ctor_Base); 5577 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 5578 getFunctionLinkage(GD)); 5579 break; 5580 } 5581 case Decl::CXXDestructor: { 5582 CodeGenPGO PGO(*this); 5583 GlobalDecl GD(cast<CXXDestructorDecl>(D), Dtor_Base); 5584 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 5585 getFunctionLinkage(GD)); 5586 break; 5587 } 5588 default: 5589 break; 5590 }; 5591 } 5592 } 5593 5594 /// Turns the given pointer into a constant. 5595 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context, 5596 const void *Ptr) { 5597 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr); 5598 llvm::Type *i64 = llvm::Type::getInt64Ty(Context); 5599 return llvm::ConstantInt::get(i64, PtrInt); 5600 } 5601 5602 static void EmitGlobalDeclMetadata(CodeGenModule &CGM, 5603 llvm::NamedMDNode *&GlobalMetadata, 5604 GlobalDecl D, 5605 llvm::GlobalValue *Addr) { 5606 if (!GlobalMetadata) 5607 GlobalMetadata = 5608 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs"); 5609 5610 // TODO: should we report variant information for ctors/dtors? 5611 llvm::Metadata *Ops[] = {llvm::ConstantAsMetadata::get(Addr), 5612 llvm::ConstantAsMetadata::get(GetPointerConstant( 5613 CGM.getLLVMContext(), D.getDecl()))}; 5614 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops)); 5615 } 5616 5617 /// For each function which is declared within an extern "C" region and marked 5618 /// as 'used', but has internal linkage, create an alias from the unmangled 5619 /// name to the mangled name if possible. People expect to be able to refer 5620 /// to such functions with an unmangled name from inline assembly within the 5621 /// same translation unit. 5622 void CodeGenModule::EmitStaticExternCAliases() { 5623 if (!getTargetCodeGenInfo().shouldEmitStaticExternCAliases()) 5624 return; 5625 for (auto &I : StaticExternCValues) { 5626 IdentifierInfo *Name = I.first; 5627 llvm::GlobalValue *Val = I.second; 5628 if (Val && !getModule().getNamedValue(Name->getName())) 5629 addUsedGlobal(llvm::GlobalAlias::create(Name->getName(), Val)); 5630 } 5631 } 5632 5633 bool CodeGenModule::lookupRepresentativeDecl(StringRef MangledName, 5634 GlobalDecl &Result) const { 5635 auto Res = Manglings.find(MangledName); 5636 if (Res == Manglings.end()) 5637 return false; 5638 Result = Res->getValue(); 5639 return true; 5640 } 5641 5642 /// Emits metadata nodes associating all the global values in the 5643 /// current module with the Decls they came from. This is useful for 5644 /// projects using IR gen as a subroutine. 5645 /// 5646 /// Since there's currently no way to associate an MDNode directly 5647 /// with an llvm::GlobalValue, we create a global named metadata 5648 /// with the name 'clang.global.decl.ptrs'. 5649 void CodeGenModule::EmitDeclMetadata() { 5650 llvm::NamedMDNode *GlobalMetadata = nullptr; 5651 5652 for (auto &I : MangledDeclNames) { 5653 llvm::GlobalValue *Addr = getModule().getNamedValue(I.second); 5654 // Some mangled names don't necessarily have an associated GlobalValue 5655 // in this module, e.g. if we mangled it for DebugInfo. 5656 if (Addr) 5657 EmitGlobalDeclMetadata(*this, GlobalMetadata, I.first, Addr); 5658 } 5659 } 5660 5661 /// Emits metadata nodes for all the local variables in the current 5662 /// function. 5663 void CodeGenFunction::EmitDeclMetadata() { 5664 if (LocalDeclMap.empty()) return; 5665 5666 llvm::LLVMContext &Context = getLLVMContext(); 5667 5668 // Find the unique metadata ID for this name. 5669 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr"); 5670 5671 llvm::NamedMDNode *GlobalMetadata = nullptr; 5672 5673 for (auto &I : LocalDeclMap) { 5674 const Decl *D = I.first; 5675 llvm::Value *Addr = I.second.getPointer(); 5676 if (auto *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) { 5677 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D); 5678 Alloca->setMetadata( 5679 DeclPtrKind, llvm::MDNode::get( 5680 Context, llvm::ValueAsMetadata::getConstant(DAddr))); 5681 } else if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr)) { 5682 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D)); 5683 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV); 5684 } 5685 } 5686 } 5687 5688 void CodeGenModule::EmitVersionIdentMetadata() { 5689 llvm::NamedMDNode *IdentMetadata = 5690 TheModule.getOrInsertNamedMetadata("llvm.ident"); 5691 std::string Version = getClangFullVersion(); 5692 llvm::LLVMContext &Ctx = TheModule.getContext(); 5693 5694 llvm::Metadata *IdentNode[] = {llvm::MDString::get(Ctx, Version)}; 5695 IdentMetadata->addOperand(llvm::MDNode::get(Ctx, IdentNode)); 5696 } 5697 5698 void CodeGenModule::EmitCommandLineMetadata() { 5699 llvm::NamedMDNode *CommandLineMetadata = 5700 TheModule.getOrInsertNamedMetadata("llvm.commandline"); 5701 std::string CommandLine = getCodeGenOpts().RecordCommandLine; 5702 llvm::LLVMContext &Ctx = TheModule.getContext(); 5703 5704 llvm::Metadata *CommandLineNode[] = {llvm::MDString::get(Ctx, CommandLine)}; 5705 CommandLineMetadata->addOperand(llvm::MDNode::get(Ctx, CommandLineNode)); 5706 } 5707 5708 void CodeGenModule::EmitTargetMetadata() { 5709 // Warning, new MangledDeclNames may be appended within this loop. 5710 // We rely on MapVector insertions adding new elements to the end 5711 // of the container. 5712 // FIXME: Move this loop into the one target that needs it, and only 5713 // loop over those declarations for which we couldn't emit the target 5714 // metadata when we emitted the declaration. 5715 for (unsigned I = 0; I != MangledDeclNames.size(); ++I) { 5716 auto Val = *(MangledDeclNames.begin() + I); 5717 const Decl *D = Val.first.getDecl()->getMostRecentDecl(); 5718 llvm::GlobalValue *GV = GetGlobalValue(Val.second); 5719 getTargetCodeGenInfo().emitTargetMD(D, GV, *this); 5720 } 5721 } 5722 5723 void CodeGenModule::EmitCoverageFile() { 5724 if (getCodeGenOpts().CoverageDataFile.empty() && 5725 getCodeGenOpts().CoverageNotesFile.empty()) 5726 return; 5727 5728 llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu"); 5729 if (!CUNode) 5730 return; 5731 5732 llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov"); 5733 llvm::LLVMContext &Ctx = TheModule.getContext(); 5734 auto *CoverageDataFile = 5735 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageDataFile); 5736 auto *CoverageNotesFile = 5737 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageNotesFile); 5738 for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) { 5739 llvm::MDNode *CU = CUNode->getOperand(i); 5740 llvm::Metadata *Elts[] = {CoverageNotesFile, CoverageDataFile, CU}; 5741 GCov->addOperand(llvm::MDNode::get(Ctx, Elts)); 5742 } 5743 } 5744 5745 llvm::Constant *CodeGenModule::EmitUuidofInitializer(StringRef Uuid) { 5746 // Sema has checked that all uuid strings are of the form 5747 // "12345678-1234-1234-1234-1234567890ab". 5748 assert(Uuid.size() == 36); 5749 for (unsigned i = 0; i < 36; ++i) { 5750 if (i == 8 || i == 13 || i == 18 || i == 23) assert(Uuid[i] == '-'); 5751 else assert(isHexDigit(Uuid[i])); 5752 } 5753 5754 // The starts of all bytes of Field3 in Uuid. Field 3 is "1234-1234567890ab". 5755 const unsigned Field3ValueOffsets[8] = { 19, 21, 24, 26, 28, 30, 32, 34 }; 5756 5757 llvm::Constant *Field3[8]; 5758 for (unsigned Idx = 0; Idx < 8; ++Idx) 5759 Field3[Idx] = llvm::ConstantInt::get( 5760 Int8Ty, Uuid.substr(Field3ValueOffsets[Idx], 2), 16); 5761 5762 llvm::Constant *Fields[4] = { 5763 llvm::ConstantInt::get(Int32Ty, Uuid.substr(0, 8), 16), 5764 llvm::ConstantInt::get(Int16Ty, Uuid.substr(9, 4), 16), 5765 llvm::ConstantInt::get(Int16Ty, Uuid.substr(14, 4), 16), 5766 llvm::ConstantArray::get(llvm::ArrayType::get(Int8Ty, 8), Field3) 5767 }; 5768 5769 return llvm::ConstantStruct::getAnon(Fields); 5770 } 5771 5772 llvm::Constant *CodeGenModule::GetAddrOfRTTIDescriptor(QualType Ty, 5773 bool ForEH) { 5774 // Return a bogus pointer if RTTI is disabled, unless it's for EH. 5775 // FIXME: should we even be calling this method if RTTI is disabled 5776 // and it's not for EH? 5777 if ((!ForEH && !getLangOpts().RTTI) || getLangOpts().CUDAIsDevice) 5778 return llvm::Constant::getNullValue(Int8PtrTy); 5779 5780 if (ForEH && Ty->isObjCObjectPointerType() && 5781 LangOpts.ObjCRuntime.isGNUFamily()) 5782 return ObjCRuntime->GetEHType(Ty); 5783 5784 return getCXXABI().getAddrOfRTTIDescriptor(Ty); 5785 } 5786 5787 void CodeGenModule::EmitOMPThreadPrivateDecl(const OMPThreadPrivateDecl *D) { 5788 // Do not emit threadprivates in simd-only mode. 5789 if (LangOpts.OpenMP && LangOpts.OpenMPSimd) 5790 return; 5791 for (auto RefExpr : D->varlists()) { 5792 auto *VD = cast<VarDecl>(cast<DeclRefExpr>(RefExpr)->getDecl()); 5793 bool PerformInit = 5794 VD->getAnyInitializer() && 5795 !VD->getAnyInitializer()->isConstantInitializer(getContext(), 5796 /*ForRef=*/false); 5797 5798 Address Addr(GetAddrOfGlobalVar(VD), getContext().getDeclAlign(VD)); 5799 if (auto InitFunction = getOpenMPRuntime().emitThreadPrivateVarDefinition( 5800 VD, Addr, RefExpr->getBeginLoc(), PerformInit)) 5801 CXXGlobalInits.push_back(InitFunction); 5802 } 5803 } 5804 5805 llvm::Metadata * 5806 CodeGenModule::CreateMetadataIdentifierImpl(QualType T, MetadataTypeMap &Map, 5807 StringRef Suffix) { 5808 llvm::Metadata *&InternalId = Map[T.getCanonicalType()]; 5809 if (InternalId) 5810 return InternalId; 5811 5812 if (isExternallyVisible(T->getLinkage())) { 5813 std::string OutName; 5814 llvm::raw_string_ostream Out(OutName); 5815 getCXXABI().getMangleContext().mangleTypeName(T, Out); 5816 Out << Suffix; 5817 5818 InternalId = llvm::MDString::get(getLLVMContext(), Out.str()); 5819 } else { 5820 InternalId = llvm::MDNode::getDistinct(getLLVMContext(), 5821 llvm::ArrayRef<llvm::Metadata *>()); 5822 } 5823 5824 return InternalId; 5825 } 5826 5827 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierForType(QualType T) { 5828 return CreateMetadataIdentifierImpl(T, MetadataIdMap, ""); 5829 } 5830 5831 llvm::Metadata * 5832 CodeGenModule::CreateMetadataIdentifierForVirtualMemPtrType(QualType T) { 5833 return CreateMetadataIdentifierImpl(T, VirtualMetadataIdMap, ".virtual"); 5834 } 5835 5836 // Generalize pointer types to a void pointer with the qualifiers of the 5837 // originally pointed-to type, e.g. 'const char *' and 'char * const *' 5838 // generalize to 'const void *' while 'char *' and 'const char **' generalize to 5839 // 'void *'. 5840 static QualType GeneralizeType(ASTContext &Ctx, QualType Ty) { 5841 if (!Ty->isPointerType()) 5842 return Ty; 5843 5844 return Ctx.getPointerType( 5845 QualType(Ctx.VoidTy).withCVRQualifiers( 5846 Ty->getPointeeType().getCVRQualifiers())); 5847 } 5848 5849 // Apply type generalization to a FunctionType's return and argument types 5850 static QualType GeneralizeFunctionType(ASTContext &Ctx, QualType Ty) { 5851 if (auto *FnType = Ty->getAs<FunctionProtoType>()) { 5852 SmallVector<QualType, 8> GeneralizedParams; 5853 for (auto &Param : FnType->param_types()) 5854 GeneralizedParams.push_back(GeneralizeType(Ctx, Param)); 5855 5856 return Ctx.getFunctionType( 5857 GeneralizeType(Ctx, FnType->getReturnType()), 5858 GeneralizedParams, FnType->getExtProtoInfo()); 5859 } 5860 5861 if (auto *FnType = Ty->getAs<FunctionNoProtoType>()) 5862 return Ctx.getFunctionNoProtoType( 5863 GeneralizeType(Ctx, FnType->getReturnType())); 5864 5865 llvm_unreachable("Encountered unknown FunctionType"); 5866 } 5867 5868 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierGeneralized(QualType T) { 5869 return CreateMetadataIdentifierImpl(GeneralizeFunctionType(getContext(), T), 5870 GeneralizedMetadataIdMap, ".generalized"); 5871 } 5872 5873 /// Returns whether this module needs the "all-vtables" type identifier. 5874 bool CodeGenModule::NeedAllVtablesTypeId() const { 5875 // Returns true if at least one of vtable-based CFI checkers is enabled and 5876 // is not in the trapping mode. 5877 return ((LangOpts.Sanitize.has(SanitizerKind::CFIVCall) && 5878 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIVCall)) || 5879 (LangOpts.Sanitize.has(SanitizerKind::CFINVCall) && 5880 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFINVCall)) || 5881 (LangOpts.Sanitize.has(SanitizerKind::CFIDerivedCast) && 5882 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIDerivedCast)) || 5883 (LangOpts.Sanitize.has(SanitizerKind::CFIUnrelatedCast) && 5884 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIUnrelatedCast))); 5885 } 5886 5887 void CodeGenModule::AddVTableTypeMetadata(llvm::GlobalVariable *VTable, 5888 CharUnits Offset, 5889 const CXXRecordDecl *RD) { 5890 llvm::Metadata *MD = 5891 CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0)); 5892 VTable->addTypeMetadata(Offset.getQuantity(), MD); 5893 5894 if (CodeGenOpts.SanitizeCfiCrossDso) 5895 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD)) 5896 VTable->addTypeMetadata(Offset.getQuantity(), 5897 llvm::ConstantAsMetadata::get(CrossDsoTypeId)); 5898 5899 if (NeedAllVtablesTypeId()) { 5900 llvm::Metadata *MD = llvm::MDString::get(getLLVMContext(), "all-vtables"); 5901 VTable->addTypeMetadata(Offset.getQuantity(), MD); 5902 } 5903 } 5904 5905 llvm::SanitizerStatReport &CodeGenModule::getSanStats() { 5906 if (!SanStats) 5907 SanStats = std::make_unique<llvm::SanitizerStatReport>(&getModule()); 5908 5909 return *SanStats; 5910 } 5911 llvm::Value * 5912 CodeGenModule::createOpenCLIntToSamplerConversion(const Expr *E, 5913 CodeGenFunction &CGF) { 5914 llvm::Constant *C = ConstantEmitter(CGF).emitAbstract(E, E->getType()); 5915 auto SamplerT = getOpenCLRuntime().getSamplerType(E->getType().getTypePtr()); 5916 auto FTy = llvm::FunctionType::get(SamplerT, {C->getType()}, false); 5917 return CGF.Builder.CreateCall(CreateRuntimeFunction(FTy, 5918 "__translate_sampler_initializer"), 5919 {C}); 5920 } 5921