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 "ABIInfo.h" 15 #include "CGBlocks.h" 16 #include "CGCUDARuntime.h" 17 #include "CGCXXABI.h" 18 #include "CGCall.h" 19 #include "CGDebugInfo.h" 20 #include "CGHLSLRuntime.h" 21 #include "CGObjCRuntime.h" 22 #include "CGOpenCLRuntime.h" 23 #include "CGOpenMPRuntime.h" 24 #include "CGOpenMPRuntimeGPU.h" 25 #include "CodeGenFunction.h" 26 #include "CodeGenPGO.h" 27 #include "ConstantEmitter.h" 28 #include "CoverageMappingGen.h" 29 #include "TargetInfo.h" 30 #include "clang/AST/ASTContext.h" 31 #include "clang/AST/ASTLambda.h" 32 #include "clang/AST/CharUnits.h" 33 #include "clang/AST/Decl.h" 34 #include "clang/AST/DeclCXX.h" 35 #include "clang/AST/DeclObjC.h" 36 #include "clang/AST/DeclTemplate.h" 37 #include "clang/AST/Mangle.h" 38 #include "clang/AST/RecursiveASTVisitor.h" 39 #include "clang/AST/StmtVisitor.h" 40 #include "clang/Basic/Builtins.h" 41 #include "clang/Basic/CharInfo.h" 42 #include "clang/Basic/CodeGenOptions.h" 43 #include "clang/Basic/Diagnostic.h" 44 #include "clang/Basic/FileManager.h" 45 #include "clang/Basic/Module.h" 46 #include "clang/Basic/SourceManager.h" 47 #include "clang/Basic/TargetInfo.h" 48 #include "clang/Basic/Version.h" 49 #include "clang/CodeGen/BackendUtil.h" 50 #include "clang/CodeGen/ConstantInitBuilder.h" 51 #include "clang/Frontend/FrontendDiagnostic.h" 52 #include "llvm/ADT/STLExtras.h" 53 #include "llvm/ADT/StringExtras.h" 54 #include "llvm/ADT/StringSwitch.h" 55 #include "llvm/Analysis/TargetLibraryInfo.h" 56 #include "llvm/Frontend/OpenMP/OMPIRBuilder.h" 57 #include "llvm/IR/AttributeMask.h" 58 #include "llvm/IR/CallingConv.h" 59 #include "llvm/IR/DataLayout.h" 60 #include "llvm/IR/Intrinsics.h" 61 #include "llvm/IR/LLVMContext.h" 62 #include "llvm/IR/Module.h" 63 #include "llvm/IR/ProfileSummary.h" 64 #include "llvm/ProfileData/InstrProfReader.h" 65 #include "llvm/ProfileData/SampleProf.h" 66 #include "llvm/Support/CRC.h" 67 #include "llvm/Support/CodeGen.h" 68 #include "llvm/Support/CommandLine.h" 69 #include "llvm/Support/ConvertUTF.h" 70 #include "llvm/Support/ErrorHandling.h" 71 #include "llvm/Support/RISCVISAInfo.h" 72 #include "llvm/Support/TimeProfiler.h" 73 #include "llvm/Support/xxhash.h" 74 #include "llvm/TargetParser/Triple.h" 75 #include "llvm/TargetParser/X86TargetParser.h" 76 #include <optional> 77 78 using namespace clang; 79 using namespace CodeGen; 80 81 static llvm::cl::opt<bool> LimitedCoverage( 82 "limited-coverage-experimental", llvm::cl::Hidden, 83 llvm::cl::desc("Emit limited coverage mapping information (experimental)")); 84 85 static const char AnnotationSection[] = "llvm.metadata"; 86 87 static CGCXXABI *createCXXABI(CodeGenModule &CGM) { 88 switch (CGM.getContext().getCXXABIKind()) { 89 case TargetCXXABI::AppleARM64: 90 case TargetCXXABI::Fuchsia: 91 case TargetCXXABI::GenericAArch64: 92 case TargetCXXABI::GenericARM: 93 case TargetCXXABI::iOS: 94 case TargetCXXABI::WatchOS: 95 case TargetCXXABI::GenericMIPS: 96 case TargetCXXABI::GenericItanium: 97 case TargetCXXABI::WebAssembly: 98 case TargetCXXABI::XL: 99 return CreateItaniumCXXABI(CGM); 100 case TargetCXXABI::Microsoft: 101 return CreateMicrosoftCXXABI(CGM); 102 } 103 104 llvm_unreachable("invalid C++ ABI kind"); 105 } 106 107 static std::unique_ptr<TargetCodeGenInfo> 108 createTargetCodeGenInfo(CodeGenModule &CGM) { 109 const TargetInfo &Target = CGM.getTarget(); 110 const llvm::Triple &Triple = Target.getTriple(); 111 const CodeGenOptions &CodeGenOpts = CGM.getCodeGenOpts(); 112 113 switch (Triple.getArch()) { 114 default: 115 return createDefaultTargetCodeGenInfo(CGM); 116 117 case llvm::Triple::le32: 118 return createPNaClTargetCodeGenInfo(CGM); 119 case llvm::Triple::m68k: 120 return createM68kTargetCodeGenInfo(CGM); 121 case llvm::Triple::mips: 122 case llvm::Triple::mipsel: 123 if (Triple.getOS() == llvm::Triple::NaCl) 124 return createPNaClTargetCodeGenInfo(CGM); 125 return createMIPSTargetCodeGenInfo(CGM, /*IsOS32=*/true); 126 127 case llvm::Triple::mips64: 128 case llvm::Triple::mips64el: 129 return createMIPSTargetCodeGenInfo(CGM, /*IsOS32=*/false); 130 131 case llvm::Triple::avr: { 132 // For passing parameters, R8~R25 are used on avr, and R18~R25 are used 133 // on avrtiny. For passing return value, R18~R25 are used on avr, and 134 // R22~R25 are used on avrtiny. 135 unsigned NPR = Target.getABI() == "avrtiny" ? 6 : 18; 136 unsigned NRR = Target.getABI() == "avrtiny" ? 4 : 8; 137 return createAVRTargetCodeGenInfo(CGM, NPR, NRR); 138 } 139 140 case llvm::Triple::aarch64: 141 case llvm::Triple::aarch64_32: 142 case llvm::Triple::aarch64_be: { 143 AArch64ABIKind Kind = AArch64ABIKind::AAPCS; 144 if (Target.getABI() == "darwinpcs") 145 Kind = AArch64ABIKind::DarwinPCS; 146 else if (Triple.isOSWindows()) 147 return createWindowsAArch64TargetCodeGenInfo(CGM, AArch64ABIKind::Win64); 148 else if (Target.getABI() == "aapcs-soft") 149 Kind = AArch64ABIKind::AAPCSSoft; 150 151 return createAArch64TargetCodeGenInfo(CGM, Kind); 152 } 153 154 case llvm::Triple::wasm32: 155 case llvm::Triple::wasm64: { 156 WebAssemblyABIKind Kind = WebAssemblyABIKind::MVP; 157 if (Target.getABI() == "experimental-mv") 158 Kind = WebAssemblyABIKind::ExperimentalMV; 159 return createWebAssemblyTargetCodeGenInfo(CGM, Kind); 160 } 161 162 case llvm::Triple::arm: 163 case llvm::Triple::armeb: 164 case llvm::Triple::thumb: 165 case llvm::Triple::thumbeb: { 166 if (Triple.getOS() == llvm::Triple::Win32) 167 return createWindowsARMTargetCodeGenInfo(CGM, ARMABIKind::AAPCS_VFP); 168 169 ARMABIKind Kind = ARMABIKind::AAPCS; 170 StringRef ABIStr = Target.getABI(); 171 if (ABIStr == "apcs-gnu") 172 Kind = ARMABIKind::APCS; 173 else if (ABIStr == "aapcs16") 174 Kind = ARMABIKind::AAPCS16_VFP; 175 else if (CodeGenOpts.FloatABI == "hard" || 176 (CodeGenOpts.FloatABI != "soft" && 177 (Triple.getEnvironment() == llvm::Triple::GNUEABIHF || 178 Triple.getEnvironment() == llvm::Triple::MuslEABIHF || 179 Triple.getEnvironment() == llvm::Triple::EABIHF))) 180 Kind = ARMABIKind::AAPCS_VFP; 181 182 return createARMTargetCodeGenInfo(CGM, Kind); 183 } 184 185 case llvm::Triple::ppc: { 186 if (Triple.isOSAIX()) 187 return createAIXTargetCodeGenInfo(CGM, /*Is64Bit=*/false); 188 189 bool IsSoftFloat = 190 CodeGenOpts.FloatABI == "soft" || Target.hasFeature("spe"); 191 return createPPC32TargetCodeGenInfo(CGM, IsSoftFloat); 192 } 193 case llvm::Triple::ppcle: { 194 bool IsSoftFloat = CodeGenOpts.FloatABI == "soft"; 195 return createPPC32TargetCodeGenInfo(CGM, IsSoftFloat); 196 } 197 case llvm::Triple::ppc64: 198 if (Triple.isOSAIX()) 199 return createAIXTargetCodeGenInfo(CGM, /*Is64Bit=*/true); 200 201 if (Triple.isOSBinFormatELF()) { 202 PPC64_SVR4_ABIKind Kind = PPC64_SVR4_ABIKind::ELFv1; 203 if (Target.getABI() == "elfv2") 204 Kind = PPC64_SVR4_ABIKind::ELFv2; 205 bool IsSoftFloat = CodeGenOpts.FloatABI == "soft"; 206 207 return createPPC64_SVR4_TargetCodeGenInfo(CGM, Kind, IsSoftFloat); 208 } 209 return createPPC64TargetCodeGenInfo(CGM); 210 case llvm::Triple::ppc64le: { 211 assert(Triple.isOSBinFormatELF() && "PPC64 LE non-ELF not supported!"); 212 PPC64_SVR4_ABIKind Kind = PPC64_SVR4_ABIKind::ELFv2; 213 if (Target.getABI() == "elfv1") 214 Kind = PPC64_SVR4_ABIKind::ELFv1; 215 bool IsSoftFloat = CodeGenOpts.FloatABI == "soft"; 216 217 return createPPC64_SVR4_TargetCodeGenInfo(CGM, Kind, IsSoftFloat); 218 } 219 220 case llvm::Triple::nvptx: 221 case llvm::Triple::nvptx64: 222 return createNVPTXTargetCodeGenInfo(CGM); 223 224 case llvm::Triple::msp430: 225 return createMSP430TargetCodeGenInfo(CGM); 226 227 case llvm::Triple::riscv32: 228 case llvm::Triple::riscv64: { 229 StringRef ABIStr = Target.getABI(); 230 unsigned XLen = Target.getPointerWidth(LangAS::Default); 231 unsigned ABIFLen = 0; 232 if (ABIStr.ends_with("f")) 233 ABIFLen = 32; 234 else if (ABIStr.ends_with("d")) 235 ABIFLen = 64; 236 bool EABI = ABIStr.ends_with("e"); 237 return createRISCVTargetCodeGenInfo(CGM, XLen, ABIFLen, EABI); 238 } 239 240 case llvm::Triple::systemz: { 241 bool SoftFloat = CodeGenOpts.FloatABI == "soft"; 242 bool HasVector = !SoftFloat && Target.getABI() == "vector"; 243 return createSystemZTargetCodeGenInfo(CGM, HasVector, SoftFloat); 244 } 245 246 case llvm::Triple::tce: 247 case llvm::Triple::tcele: 248 return createTCETargetCodeGenInfo(CGM); 249 250 case llvm::Triple::x86: { 251 bool IsDarwinVectorABI = Triple.isOSDarwin(); 252 bool IsWin32FloatStructABI = Triple.isOSWindows() && !Triple.isOSCygMing(); 253 254 if (Triple.getOS() == llvm::Triple::Win32) { 255 return createWinX86_32TargetCodeGenInfo( 256 CGM, IsDarwinVectorABI, IsWin32FloatStructABI, 257 CodeGenOpts.NumRegisterParameters); 258 } 259 return createX86_32TargetCodeGenInfo( 260 CGM, IsDarwinVectorABI, IsWin32FloatStructABI, 261 CodeGenOpts.NumRegisterParameters, CodeGenOpts.FloatABI == "soft"); 262 } 263 264 case llvm::Triple::x86_64: { 265 StringRef ABI = Target.getABI(); 266 X86AVXABILevel AVXLevel = (ABI == "avx512" ? X86AVXABILevel::AVX512 267 : ABI == "avx" ? X86AVXABILevel::AVX 268 : X86AVXABILevel::None); 269 270 switch (Triple.getOS()) { 271 case llvm::Triple::Win32: 272 return createWinX86_64TargetCodeGenInfo(CGM, AVXLevel); 273 default: 274 return createX86_64TargetCodeGenInfo(CGM, AVXLevel); 275 } 276 } 277 case llvm::Triple::hexagon: 278 return createHexagonTargetCodeGenInfo(CGM); 279 case llvm::Triple::lanai: 280 return createLanaiTargetCodeGenInfo(CGM); 281 case llvm::Triple::r600: 282 return createAMDGPUTargetCodeGenInfo(CGM); 283 case llvm::Triple::amdgcn: 284 return createAMDGPUTargetCodeGenInfo(CGM); 285 case llvm::Triple::sparc: 286 return createSparcV8TargetCodeGenInfo(CGM); 287 case llvm::Triple::sparcv9: 288 return createSparcV9TargetCodeGenInfo(CGM); 289 case llvm::Triple::xcore: 290 return createXCoreTargetCodeGenInfo(CGM); 291 case llvm::Triple::arc: 292 return createARCTargetCodeGenInfo(CGM); 293 case llvm::Triple::spir: 294 case llvm::Triple::spir64: 295 return createCommonSPIRTargetCodeGenInfo(CGM); 296 case llvm::Triple::spirv32: 297 case llvm::Triple::spirv64: 298 return createSPIRVTargetCodeGenInfo(CGM); 299 case llvm::Triple::ve: 300 return createVETargetCodeGenInfo(CGM); 301 case llvm::Triple::csky: { 302 bool IsSoftFloat = !Target.hasFeature("hard-float-abi"); 303 bool hasFP64 = 304 Target.hasFeature("fpuv2_df") || Target.hasFeature("fpuv3_df"); 305 return createCSKYTargetCodeGenInfo(CGM, IsSoftFloat ? 0 306 : hasFP64 ? 64 307 : 32); 308 } 309 case llvm::Triple::bpfeb: 310 case llvm::Triple::bpfel: 311 return createBPFTargetCodeGenInfo(CGM); 312 case llvm::Triple::loongarch32: 313 case llvm::Triple::loongarch64: { 314 StringRef ABIStr = Target.getABI(); 315 unsigned ABIFRLen = 0; 316 if (ABIStr.ends_with("f")) 317 ABIFRLen = 32; 318 else if (ABIStr.ends_with("d")) 319 ABIFRLen = 64; 320 return createLoongArchTargetCodeGenInfo( 321 CGM, Target.getPointerWidth(LangAS::Default), ABIFRLen); 322 } 323 } 324 } 325 326 const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() { 327 if (!TheTargetCodeGenInfo) 328 TheTargetCodeGenInfo = createTargetCodeGenInfo(*this); 329 return *TheTargetCodeGenInfo; 330 } 331 332 CodeGenModule::CodeGenModule(ASTContext &C, 333 IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS, 334 const HeaderSearchOptions &HSO, 335 const PreprocessorOptions &PPO, 336 const CodeGenOptions &CGO, llvm::Module &M, 337 DiagnosticsEngine &diags, 338 CoverageSourceInfo *CoverageInfo) 339 : Context(C), LangOpts(C.getLangOpts()), FS(FS), HeaderSearchOpts(HSO), 340 PreprocessorOpts(PPO), CodeGenOpts(CGO), TheModule(M), Diags(diags), 341 Target(C.getTargetInfo()), ABI(createCXXABI(*this)), 342 VMContext(M.getContext()), Types(*this), VTables(*this), 343 SanitizerMD(new SanitizerMetadata(*this)) { 344 345 // Initialize the type cache. 346 llvm::LLVMContext &LLVMContext = M.getContext(); 347 VoidTy = llvm::Type::getVoidTy(LLVMContext); 348 Int8Ty = llvm::Type::getInt8Ty(LLVMContext); 349 Int16Ty = llvm::Type::getInt16Ty(LLVMContext); 350 Int32Ty = llvm::Type::getInt32Ty(LLVMContext); 351 Int64Ty = llvm::Type::getInt64Ty(LLVMContext); 352 HalfTy = llvm::Type::getHalfTy(LLVMContext); 353 BFloatTy = llvm::Type::getBFloatTy(LLVMContext); 354 FloatTy = llvm::Type::getFloatTy(LLVMContext); 355 DoubleTy = llvm::Type::getDoubleTy(LLVMContext); 356 PointerWidthInBits = C.getTargetInfo().getPointerWidth(LangAS::Default); 357 PointerAlignInBytes = 358 C.toCharUnitsFromBits(C.getTargetInfo().getPointerAlign(LangAS::Default)) 359 .getQuantity(); 360 SizeSizeInBytes = 361 C.toCharUnitsFromBits(C.getTargetInfo().getMaxPointerWidth()).getQuantity(); 362 IntAlignInBytes = 363 C.toCharUnitsFromBits(C.getTargetInfo().getIntAlign()).getQuantity(); 364 CharTy = 365 llvm::IntegerType::get(LLVMContext, C.getTargetInfo().getCharWidth()); 366 IntTy = llvm::IntegerType::get(LLVMContext, C.getTargetInfo().getIntWidth()); 367 IntPtrTy = llvm::IntegerType::get(LLVMContext, 368 C.getTargetInfo().getMaxPointerWidth()); 369 Int8PtrTy = llvm::PointerType::get(LLVMContext, 0); 370 const llvm::DataLayout &DL = M.getDataLayout(); 371 AllocaInt8PtrTy = 372 llvm::PointerType::get(LLVMContext, DL.getAllocaAddrSpace()); 373 GlobalsInt8PtrTy = 374 llvm::PointerType::get(LLVMContext, DL.getDefaultGlobalsAddressSpace()); 375 ConstGlobalsPtrTy = llvm::PointerType::get( 376 LLVMContext, C.getTargetAddressSpace(GetGlobalConstantAddressSpace())); 377 ASTAllocaAddressSpace = getTargetCodeGenInfo().getASTAllocaAddressSpace(); 378 379 // Build C++20 Module initializers. 380 // TODO: Add Microsoft here once we know the mangling required for the 381 // initializers. 382 CXX20ModuleInits = 383 LangOpts.CPlusPlusModules && getCXXABI().getMangleContext().getKind() == 384 ItaniumMangleContext::MK_Itanium; 385 386 RuntimeCC = getTargetCodeGenInfo().getABIInfo().getRuntimeCC(); 387 388 if (LangOpts.ObjC) 389 createObjCRuntime(); 390 if (LangOpts.OpenCL) 391 createOpenCLRuntime(); 392 if (LangOpts.OpenMP) 393 createOpenMPRuntime(); 394 if (LangOpts.CUDA) 395 createCUDARuntime(); 396 if (LangOpts.HLSL) 397 createHLSLRuntime(); 398 399 // Enable TBAA unless it's suppressed. ThreadSanitizer needs TBAA even at O0. 400 if (LangOpts.Sanitize.has(SanitizerKind::Thread) || 401 (!CodeGenOpts.RelaxedAliasing && CodeGenOpts.OptimizationLevel > 0)) 402 TBAA.reset(new CodeGenTBAA(Context, getTypes(), TheModule, CodeGenOpts, 403 getLangOpts(), getCXXABI().getMangleContext())); 404 405 // If debug info or coverage generation is enabled, create the CGDebugInfo 406 // object. 407 if (CodeGenOpts.getDebugInfo() != llvm::codegenoptions::NoDebugInfo || 408 CodeGenOpts.CoverageNotesFile.size() || 409 CodeGenOpts.CoverageDataFile.size()) 410 DebugInfo.reset(new CGDebugInfo(*this)); 411 412 Block.GlobalUniqueCount = 0; 413 414 if (C.getLangOpts().ObjC) 415 ObjCData.reset(new ObjCEntrypoints()); 416 417 if (CodeGenOpts.hasProfileClangUse()) { 418 auto ReaderOrErr = llvm::IndexedInstrProfReader::create( 419 CodeGenOpts.ProfileInstrumentUsePath, *FS, 420 CodeGenOpts.ProfileRemappingFile); 421 // We're checking for profile read errors in CompilerInvocation, so if 422 // there was an error it should've already been caught. If it hasn't been 423 // somehow, trip an assertion. 424 assert(ReaderOrErr); 425 PGOReader = std::move(ReaderOrErr.get()); 426 } 427 428 // If coverage mapping generation is enabled, create the 429 // CoverageMappingModuleGen object. 430 if (CodeGenOpts.CoverageMapping) 431 CoverageMapping.reset(new CoverageMappingModuleGen(*this, *CoverageInfo)); 432 433 // Generate the module name hash here if needed. 434 if (CodeGenOpts.UniqueInternalLinkageNames && 435 !getModule().getSourceFileName().empty()) { 436 std::string Path = getModule().getSourceFileName(); 437 // Check if a path substitution is needed from the MacroPrefixMap. 438 for (const auto &Entry : LangOpts.MacroPrefixMap) 439 if (Path.rfind(Entry.first, 0) != std::string::npos) { 440 Path = Entry.second + Path.substr(Entry.first.size()); 441 break; 442 } 443 ModuleNameHash = llvm::getUniqueInternalLinkagePostfix(Path); 444 } 445 } 446 447 CodeGenModule::~CodeGenModule() {} 448 449 void CodeGenModule::createObjCRuntime() { 450 // This is just isGNUFamily(), but we want to force implementors of 451 // new ABIs to decide how best to do this. 452 switch (LangOpts.ObjCRuntime.getKind()) { 453 case ObjCRuntime::GNUstep: 454 case ObjCRuntime::GCC: 455 case ObjCRuntime::ObjFW: 456 ObjCRuntime.reset(CreateGNUObjCRuntime(*this)); 457 return; 458 459 case ObjCRuntime::FragileMacOSX: 460 case ObjCRuntime::MacOSX: 461 case ObjCRuntime::iOS: 462 case ObjCRuntime::WatchOS: 463 ObjCRuntime.reset(CreateMacObjCRuntime(*this)); 464 return; 465 } 466 llvm_unreachable("bad runtime kind"); 467 } 468 469 void CodeGenModule::createOpenCLRuntime() { 470 OpenCLRuntime.reset(new CGOpenCLRuntime(*this)); 471 } 472 473 void CodeGenModule::createOpenMPRuntime() { 474 // Select a specialized code generation class based on the target, if any. 475 // If it does not exist use the default implementation. 476 switch (getTriple().getArch()) { 477 case llvm::Triple::nvptx: 478 case llvm::Triple::nvptx64: 479 case llvm::Triple::amdgcn: 480 assert(getLangOpts().OpenMPIsTargetDevice && 481 "OpenMP AMDGPU/NVPTX is only prepared to deal with device code."); 482 OpenMPRuntime.reset(new CGOpenMPRuntimeGPU(*this)); 483 break; 484 default: 485 if (LangOpts.OpenMPSimd) 486 OpenMPRuntime.reset(new CGOpenMPSIMDRuntime(*this)); 487 else 488 OpenMPRuntime.reset(new CGOpenMPRuntime(*this)); 489 break; 490 } 491 } 492 493 void CodeGenModule::createCUDARuntime() { 494 CUDARuntime.reset(CreateNVCUDARuntime(*this)); 495 } 496 497 void CodeGenModule::createHLSLRuntime() { 498 HLSLRuntime.reset(new CGHLSLRuntime(*this)); 499 } 500 501 void CodeGenModule::addReplacement(StringRef Name, llvm::Constant *C) { 502 Replacements[Name] = C; 503 } 504 505 void CodeGenModule::applyReplacements() { 506 for (auto &I : Replacements) { 507 StringRef MangledName = I.first; 508 llvm::Constant *Replacement = I.second; 509 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 510 if (!Entry) 511 continue; 512 auto *OldF = cast<llvm::Function>(Entry); 513 auto *NewF = dyn_cast<llvm::Function>(Replacement); 514 if (!NewF) { 515 if (auto *Alias = dyn_cast<llvm::GlobalAlias>(Replacement)) { 516 NewF = dyn_cast<llvm::Function>(Alias->getAliasee()); 517 } else { 518 auto *CE = cast<llvm::ConstantExpr>(Replacement); 519 assert(CE->getOpcode() == llvm::Instruction::BitCast || 520 CE->getOpcode() == llvm::Instruction::GetElementPtr); 521 NewF = dyn_cast<llvm::Function>(CE->getOperand(0)); 522 } 523 } 524 525 // Replace old with new, but keep the old order. 526 OldF->replaceAllUsesWith(Replacement); 527 if (NewF) { 528 NewF->removeFromParent(); 529 OldF->getParent()->getFunctionList().insertAfter(OldF->getIterator(), 530 NewF); 531 } 532 OldF->eraseFromParent(); 533 } 534 } 535 536 void CodeGenModule::addGlobalValReplacement(llvm::GlobalValue *GV, llvm::Constant *C) { 537 GlobalValReplacements.push_back(std::make_pair(GV, C)); 538 } 539 540 void CodeGenModule::applyGlobalValReplacements() { 541 for (auto &I : GlobalValReplacements) { 542 llvm::GlobalValue *GV = I.first; 543 llvm::Constant *C = I.second; 544 545 GV->replaceAllUsesWith(C); 546 GV->eraseFromParent(); 547 } 548 } 549 550 // This is only used in aliases that we created and we know they have a 551 // linear structure. 552 static const llvm::GlobalValue *getAliasedGlobal(const llvm::GlobalValue *GV) { 553 const llvm::Constant *C; 554 if (auto *GA = dyn_cast<llvm::GlobalAlias>(GV)) 555 C = GA->getAliasee(); 556 else if (auto *GI = dyn_cast<llvm::GlobalIFunc>(GV)) 557 C = GI->getResolver(); 558 else 559 return GV; 560 561 const auto *AliaseeGV = dyn_cast<llvm::GlobalValue>(C->stripPointerCasts()); 562 if (!AliaseeGV) 563 return nullptr; 564 565 const llvm::GlobalValue *FinalGV = AliaseeGV->getAliaseeObject(); 566 if (FinalGV == GV) 567 return nullptr; 568 569 return FinalGV; 570 } 571 572 static bool checkAliasedGlobal( 573 const ASTContext &Context, DiagnosticsEngine &Diags, SourceLocation Location, 574 bool IsIFunc, const llvm::GlobalValue *Alias, const llvm::GlobalValue *&GV, 575 const llvm::MapVector<GlobalDecl, StringRef> &MangledDeclNames, 576 SourceRange AliasRange) { 577 GV = getAliasedGlobal(Alias); 578 if (!GV) { 579 Diags.Report(Location, diag::err_cyclic_alias) << IsIFunc; 580 return false; 581 } 582 583 if (GV->hasCommonLinkage()) { 584 const llvm::Triple &Triple = Context.getTargetInfo().getTriple(); 585 if (Triple.getObjectFormat() == llvm::Triple::XCOFF) { 586 Diags.Report(Location, diag::err_alias_to_common); 587 return false; 588 } 589 } 590 591 if (GV->isDeclaration()) { 592 Diags.Report(Location, diag::err_alias_to_undefined) << IsIFunc << IsIFunc; 593 Diags.Report(Location, diag::note_alias_requires_mangled_name) 594 << IsIFunc << IsIFunc; 595 // Provide a note if the given function is not found and exists as a 596 // mangled name. 597 for (const auto &[Decl, Name] : MangledDeclNames) { 598 if (const auto *ND = dyn_cast<NamedDecl>(Decl.getDecl())) { 599 if (ND->getName() == GV->getName()) { 600 Diags.Report(Location, diag::note_alias_mangled_name_alternative) 601 << Name 602 << FixItHint::CreateReplacement( 603 AliasRange, 604 (Twine(IsIFunc ? "ifunc" : "alias") + "(\"" + Name + "\")") 605 .str()); 606 } 607 } 608 } 609 return false; 610 } 611 612 if (IsIFunc) { 613 // Check resolver function type. 614 const auto *F = dyn_cast<llvm::Function>(GV); 615 if (!F) { 616 Diags.Report(Location, diag::err_alias_to_undefined) 617 << IsIFunc << IsIFunc; 618 return false; 619 } 620 621 llvm::FunctionType *FTy = F->getFunctionType(); 622 if (!FTy->getReturnType()->isPointerTy()) { 623 Diags.Report(Location, diag::err_ifunc_resolver_return); 624 return false; 625 } 626 } 627 628 return true; 629 } 630 631 // Emit a warning if toc-data attribute is requested for global variables that 632 // have aliases and remove the toc-data attribute. 633 static void checkAliasForTocData(llvm::GlobalVariable *GVar, 634 const CodeGenOptions &CodeGenOpts, 635 DiagnosticsEngine &Diags, 636 SourceLocation Location) { 637 if (GVar->hasAttribute("toc-data")) { 638 auto GVId = GVar->getName(); 639 // Is this a global variable specified by the user as local? 640 if ((llvm::binary_search(CodeGenOpts.TocDataVarsUserSpecified, GVId))) { 641 Diags.Report(Location, diag::warn_toc_unsupported_type) 642 << GVId << "the variable has an alias"; 643 } 644 llvm::AttributeSet CurrAttributes = GVar->getAttributes(); 645 llvm::AttributeSet NewAttributes = 646 CurrAttributes.removeAttribute(GVar->getContext(), "toc-data"); 647 GVar->setAttributes(NewAttributes); 648 } 649 } 650 651 void CodeGenModule::checkAliases() { 652 // Check if the constructed aliases are well formed. It is really unfortunate 653 // that we have to do this in CodeGen, but we only construct mangled names 654 // and aliases during codegen. 655 bool Error = false; 656 DiagnosticsEngine &Diags = getDiags(); 657 for (const GlobalDecl &GD : Aliases) { 658 const auto *D = cast<ValueDecl>(GD.getDecl()); 659 SourceLocation Location; 660 SourceRange Range; 661 bool IsIFunc = D->hasAttr<IFuncAttr>(); 662 if (const Attr *A = D->getDefiningAttr()) { 663 Location = A->getLocation(); 664 Range = A->getRange(); 665 } else 666 llvm_unreachable("Not an alias or ifunc?"); 667 668 StringRef MangledName = getMangledName(GD); 669 llvm::GlobalValue *Alias = GetGlobalValue(MangledName); 670 const llvm::GlobalValue *GV = nullptr; 671 if (!checkAliasedGlobal(getContext(), Diags, Location, IsIFunc, Alias, GV, 672 MangledDeclNames, Range)) { 673 Error = true; 674 continue; 675 } 676 677 if (getContext().getTargetInfo().getTriple().isOSAIX()) 678 if (const llvm::GlobalVariable *GVar = 679 dyn_cast<const llvm::GlobalVariable>(GV)) 680 checkAliasForTocData(const_cast<llvm::GlobalVariable *>(GVar), 681 getCodeGenOpts(), Diags, Location); 682 683 llvm::Constant *Aliasee = 684 IsIFunc ? cast<llvm::GlobalIFunc>(Alias)->getResolver() 685 : cast<llvm::GlobalAlias>(Alias)->getAliasee(); 686 687 llvm::GlobalValue *AliaseeGV; 688 if (auto CE = dyn_cast<llvm::ConstantExpr>(Aliasee)) 689 AliaseeGV = cast<llvm::GlobalValue>(CE->getOperand(0)); 690 else 691 AliaseeGV = cast<llvm::GlobalValue>(Aliasee); 692 693 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) { 694 StringRef AliasSection = SA->getName(); 695 if (AliasSection != AliaseeGV->getSection()) 696 Diags.Report(SA->getLocation(), diag::warn_alias_with_section) 697 << AliasSection << IsIFunc << IsIFunc; 698 } 699 700 // We have to handle alias to weak aliases in here. LLVM itself disallows 701 // this since the object semantics would not match the IL one. For 702 // compatibility with gcc we implement it by just pointing the alias 703 // to its aliasee's aliasee. We also warn, since the user is probably 704 // expecting the link to be weak. 705 if (auto *GA = dyn_cast<llvm::GlobalAlias>(AliaseeGV)) { 706 if (GA->isInterposable()) { 707 Diags.Report(Location, diag::warn_alias_to_weak_alias) 708 << GV->getName() << GA->getName() << IsIFunc; 709 Aliasee = llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast( 710 GA->getAliasee(), Alias->getType()); 711 712 if (IsIFunc) 713 cast<llvm::GlobalIFunc>(Alias)->setResolver(Aliasee); 714 else 715 cast<llvm::GlobalAlias>(Alias)->setAliasee(Aliasee); 716 } 717 } 718 } 719 if (!Error) 720 return; 721 722 for (const GlobalDecl &GD : Aliases) { 723 StringRef MangledName = getMangledName(GD); 724 llvm::GlobalValue *Alias = GetGlobalValue(MangledName); 725 Alias->replaceAllUsesWith(llvm::UndefValue::get(Alias->getType())); 726 Alias->eraseFromParent(); 727 } 728 } 729 730 void CodeGenModule::clear() { 731 DeferredDeclsToEmit.clear(); 732 EmittedDeferredDecls.clear(); 733 DeferredAnnotations.clear(); 734 if (OpenMPRuntime) 735 OpenMPRuntime->clear(); 736 } 737 738 void InstrProfStats::reportDiagnostics(DiagnosticsEngine &Diags, 739 StringRef MainFile) { 740 if (!hasDiagnostics()) 741 return; 742 if (VisitedInMainFile > 0 && VisitedInMainFile == MissingInMainFile) { 743 if (MainFile.empty()) 744 MainFile = "<stdin>"; 745 Diags.Report(diag::warn_profile_data_unprofiled) << MainFile; 746 } else { 747 if (Mismatched > 0) 748 Diags.Report(diag::warn_profile_data_out_of_date) << Visited << Mismatched; 749 750 if (Missing > 0) 751 Diags.Report(diag::warn_profile_data_missing) << Visited << Missing; 752 } 753 } 754 755 static std::optional<llvm::GlobalValue::VisibilityTypes> 756 getLLVMVisibility(clang::LangOptions::VisibilityFromDLLStorageClassKinds K) { 757 // Map to LLVM visibility. 758 switch (K) { 759 case clang::LangOptions::VisibilityFromDLLStorageClassKinds::Keep: 760 return std::nullopt; 761 case clang::LangOptions::VisibilityFromDLLStorageClassKinds::Default: 762 return llvm::GlobalValue::DefaultVisibility; 763 case clang::LangOptions::VisibilityFromDLLStorageClassKinds::Hidden: 764 return llvm::GlobalValue::HiddenVisibility; 765 case clang::LangOptions::VisibilityFromDLLStorageClassKinds::Protected: 766 return llvm::GlobalValue::ProtectedVisibility; 767 } 768 llvm_unreachable("unknown option value!"); 769 } 770 771 void setLLVMVisibility(llvm::GlobalValue &GV, 772 std::optional<llvm::GlobalValue::VisibilityTypes> V) { 773 if (!V) 774 return; 775 776 // Reset DSO locality before setting the visibility. This removes 777 // any effects that visibility options and annotations may have 778 // had on the DSO locality. Setting the visibility will implicitly set 779 // appropriate globals to DSO Local; however, this will be pessimistic 780 // w.r.t. to the normal compiler IRGen. 781 GV.setDSOLocal(false); 782 GV.setVisibility(*V); 783 } 784 785 static void setVisibilityFromDLLStorageClass(const clang::LangOptions &LO, 786 llvm::Module &M) { 787 if (!LO.VisibilityFromDLLStorageClass) 788 return; 789 790 std::optional<llvm::GlobalValue::VisibilityTypes> DLLExportVisibility = 791 getLLVMVisibility(LO.getDLLExportVisibility()); 792 793 std::optional<llvm::GlobalValue::VisibilityTypes> 794 NoDLLStorageClassVisibility = 795 getLLVMVisibility(LO.getNoDLLStorageClassVisibility()); 796 797 std::optional<llvm::GlobalValue::VisibilityTypes> 798 ExternDeclDLLImportVisibility = 799 getLLVMVisibility(LO.getExternDeclDLLImportVisibility()); 800 801 std::optional<llvm::GlobalValue::VisibilityTypes> 802 ExternDeclNoDLLStorageClassVisibility = 803 getLLVMVisibility(LO.getExternDeclNoDLLStorageClassVisibility()); 804 805 for (llvm::GlobalValue &GV : M.global_values()) { 806 if (GV.hasAppendingLinkage() || GV.hasLocalLinkage()) 807 continue; 808 809 if (GV.isDeclarationForLinker()) 810 setLLVMVisibility(GV, GV.getDLLStorageClass() == 811 llvm::GlobalValue::DLLImportStorageClass 812 ? ExternDeclDLLImportVisibility 813 : ExternDeclNoDLLStorageClassVisibility); 814 else 815 setLLVMVisibility(GV, GV.getDLLStorageClass() == 816 llvm::GlobalValue::DLLExportStorageClass 817 ? DLLExportVisibility 818 : NoDLLStorageClassVisibility); 819 820 GV.setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass); 821 } 822 } 823 824 static bool isStackProtectorOn(const LangOptions &LangOpts, 825 const llvm::Triple &Triple, 826 clang::LangOptions::StackProtectorMode Mode) { 827 if (Triple.isAMDGPU() || Triple.isNVPTX()) 828 return false; 829 return LangOpts.getStackProtector() == Mode; 830 } 831 832 void CodeGenModule::Release() { 833 Module *Primary = getContext().getCurrentNamedModule(); 834 if (CXX20ModuleInits && Primary && !Primary->isHeaderLikeModule()) 835 EmitModuleInitializers(Primary); 836 EmitDeferred(); 837 DeferredDecls.insert(EmittedDeferredDecls.begin(), 838 EmittedDeferredDecls.end()); 839 EmittedDeferredDecls.clear(); 840 EmitVTablesOpportunistically(); 841 applyGlobalValReplacements(); 842 applyReplacements(); 843 emitMultiVersionFunctions(); 844 845 if (Context.getLangOpts().IncrementalExtensions && 846 GlobalTopLevelStmtBlockInFlight.first) { 847 const TopLevelStmtDecl *TLSD = GlobalTopLevelStmtBlockInFlight.second; 848 GlobalTopLevelStmtBlockInFlight.first->FinishFunction(TLSD->getEndLoc()); 849 GlobalTopLevelStmtBlockInFlight = {nullptr, nullptr}; 850 } 851 852 // Module implementations are initialized the same way as a regular TU that 853 // imports one or more modules. 854 if (CXX20ModuleInits && Primary && Primary->isInterfaceOrPartition()) 855 EmitCXXModuleInitFunc(Primary); 856 else 857 EmitCXXGlobalInitFunc(); 858 EmitCXXGlobalCleanUpFunc(); 859 registerGlobalDtorsWithAtExit(); 860 EmitCXXThreadLocalInitFunc(); 861 if (ObjCRuntime) 862 if (llvm::Function *ObjCInitFunction = ObjCRuntime->ModuleInitFunction()) 863 AddGlobalCtor(ObjCInitFunction); 864 if (Context.getLangOpts().CUDA && CUDARuntime) { 865 if (llvm::Function *CudaCtorFunction = CUDARuntime->finalizeModule()) 866 AddGlobalCtor(CudaCtorFunction); 867 } 868 if (OpenMPRuntime) { 869 OpenMPRuntime->createOffloadEntriesAndInfoMetadata(); 870 OpenMPRuntime->clear(); 871 } 872 if (PGOReader) { 873 getModule().setProfileSummary( 874 PGOReader->getSummary(/* UseCS */ false).getMD(VMContext), 875 llvm::ProfileSummary::PSK_Instr); 876 if (PGOStats.hasDiagnostics()) 877 PGOStats.reportDiagnostics(getDiags(), getCodeGenOpts().MainFileName); 878 } 879 llvm::stable_sort(GlobalCtors, [](const Structor &L, const Structor &R) { 880 return L.LexOrder < R.LexOrder; 881 }); 882 EmitCtorList(GlobalCtors, "llvm.global_ctors"); 883 EmitCtorList(GlobalDtors, "llvm.global_dtors"); 884 EmitGlobalAnnotations(); 885 EmitStaticExternCAliases(); 886 checkAliases(); 887 EmitDeferredUnusedCoverageMappings(); 888 CodeGenPGO(*this).setValueProfilingFlag(getModule()); 889 CodeGenPGO(*this).setProfileVersion(getModule()); 890 if (CoverageMapping) 891 CoverageMapping->emit(); 892 if (CodeGenOpts.SanitizeCfiCrossDso) { 893 CodeGenFunction(*this).EmitCfiCheckFail(); 894 CodeGenFunction(*this).EmitCfiCheckStub(); 895 } 896 if (LangOpts.Sanitize.has(SanitizerKind::KCFI)) 897 finalizeKCFITypes(); 898 emitAtAvailableLinkGuard(); 899 if (Context.getTargetInfo().getTriple().isWasm()) 900 EmitMainVoidAlias(); 901 902 if (getTriple().isAMDGPU()) { 903 // Emit amdhsa_code_object_version module flag, which is code object version 904 // times 100. 905 if (getTarget().getTargetOpts().CodeObjectVersion != 906 llvm::CodeObjectVersionKind::COV_None) { 907 getModule().addModuleFlag(llvm::Module::Error, 908 "amdhsa_code_object_version", 909 getTarget().getTargetOpts().CodeObjectVersion); 910 } 911 912 // Currently, "-mprintf-kind" option is only supported for HIP 913 if (LangOpts.HIP) { 914 auto *MDStr = llvm::MDString::get( 915 getLLVMContext(), (getTarget().getTargetOpts().AMDGPUPrintfKindVal == 916 TargetOptions::AMDGPUPrintfKind::Hostcall) 917 ? "hostcall" 918 : "buffered"); 919 getModule().addModuleFlag(llvm::Module::Error, "amdgpu_printf_kind", 920 MDStr); 921 } 922 } 923 924 // Emit a global array containing all external kernels or device variables 925 // used by host functions and mark it as used for CUDA/HIP. This is necessary 926 // to get kernels or device variables in archives linked in even if these 927 // kernels or device variables are only used in host functions. 928 if (!Context.CUDAExternalDeviceDeclODRUsedByHost.empty()) { 929 SmallVector<llvm::Constant *, 8> UsedArray; 930 for (auto D : Context.CUDAExternalDeviceDeclODRUsedByHost) { 931 GlobalDecl GD; 932 if (auto *FD = dyn_cast<FunctionDecl>(D)) 933 GD = GlobalDecl(FD, KernelReferenceKind::Kernel); 934 else 935 GD = GlobalDecl(D); 936 UsedArray.push_back(llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast( 937 GetAddrOfGlobal(GD), Int8PtrTy)); 938 } 939 940 llvm::ArrayType *ATy = llvm::ArrayType::get(Int8PtrTy, UsedArray.size()); 941 942 auto *GV = new llvm::GlobalVariable( 943 getModule(), ATy, false, llvm::GlobalValue::InternalLinkage, 944 llvm::ConstantArray::get(ATy, UsedArray), "__clang_gpu_used_external"); 945 addCompilerUsedGlobal(GV); 946 } 947 if (LangOpts.HIP && !getLangOpts().OffloadingNewDriver) { 948 // Emit a unique ID so that host and device binaries from the same 949 // compilation unit can be associated. 950 auto *GV = new llvm::GlobalVariable( 951 getModule(), Int8Ty, false, llvm::GlobalValue::ExternalLinkage, 952 llvm::Constant::getNullValue(Int8Ty), 953 "__hip_cuid_" + getContext().getCUIDHash()); 954 addCompilerUsedGlobal(GV); 955 } 956 emitLLVMUsed(); 957 if (SanStats) 958 SanStats->finish(); 959 960 if (CodeGenOpts.Autolink && 961 (Context.getLangOpts().Modules || !LinkerOptionsMetadata.empty())) { 962 EmitModuleLinkOptions(); 963 } 964 965 // On ELF we pass the dependent library specifiers directly to the linker 966 // without manipulating them. This is in contrast to other platforms where 967 // they are mapped to a specific linker option by the compiler. This 968 // difference is a result of the greater variety of ELF linkers and the fact 969 // that ELF linkers tend to handle libraries in a more complicated fashion 970 // than on other platforms. This forces us to defer handling the dependent 971 // libs to the linker. 972 // 973 // CUDA/HIP device and host libraries are different. Currently there is no 974 // way to differentiate dependent libraries for host or device. Existing 975 // usage of #pragma comment(lib, *) is intended for host libraries on 976 // Windows. Therefore emit llvm.dependent-libraries only for host. 977 if (!ELFDependentLibraries.empty() && !Context.getLangOpts().CUDAIsDevice) { 978 auto *NMD = getModule().getOrInsertNamedMetadata("llvm.dependent-libraries"); 979 for (auto *MD : ELFDependentLibraries) 980 NMD->addOperand(MD); 981 } 982 983 // Record mregparm value now so it is visible through rest of codegen. 984 if (Context.getTargetInfo().getTriple().getArch() == llvm::Triple::x86) 985 getModule().addModuleFlag(llvm::Module::Error, "NumRegisterParameters", 986 CodeGenOpts.NumRegisterParameters); 987 988 if (CodeGenOpts.DwarfVersion) { 989 getModule().addModuleFlag(llvm::Module::Max, "Dwarf Version", 990 CodeGenOpts.DwarfVersion); 991 } 992 993 if (CodeGenOpts.Dwarf64) 994 getModule().addModuleFlag(llvm::Module::Max, "DWARF64", 1); 995 996 if (Context.getLangOpts().SemanticInterposition) 997 // Require various optimization to respect semantic interposition. 998 getModule().setSemanticInterposition(true); 999 1000 if (CodeGenOpts.EmitCodeView) { 1001 // Indicate that we want CodeView in the metadata. 1002 getModule().addModuleFlag(llvm::Module::Warning, "CodeView", 1); 1003 } 1004 if (CodeGenOpts.CodeViewGHash) { 1005 getModule().addModuleFlag(llvm::Module::Warning, "CodeViewGHash", 1); 1006 } 1007 if (CodeGenOpts.ControlFlowGuard) { 1008 // Function ID tables and checks for Control Flow Guard (cfguard=2). 1009 getModule().addModuleFlag(llvm::Module::Warning, "cfguard", 2); 1010 } else if (CodeGenOpts.ControlFlowGuardNoChecks) { 1011 // Function ID tables for Control Flow Guard (cfguard=1). 1012 getModule().addModuleFlag(llvm::Module::Warning, "cfguard", 1); 1013 } 1014 if (CodeGenOpts.EHContGuard) { 1015 // Function ID tables for EH Continuation Guard. 1016 getModule().addModuleFlag(llvm::Module::Warning, "ehcontguard", 1); 1017 } 1018 if (Context.getLangOpts().Kernel) { 1019 // Note if we are compiling with /kernel. 1020 getModule().addModuleFlag(llvm::Module::Warning, "ms-kernel", 1); 1021 } 1022 if (CodeGenOpts.OptimizationLevel > 0 && CodeGenOpts.StrictVTablePointers) { 1023 // We don't support LTO with 2 with different StrictVTablePointers 1024 // FIXME: we could support it by stripping all the information introduced 1025 // by StrictVTablePointers. 1026 1027 getModule().addModuleFlag(llvm::Module::Error, "StrictVTablePointers",1); 1028 1029 llvm::Metadata *Ops[2] = { 1030 llvm::MDString::get(VMContext, "StrictVTablePointers"), 1031 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 1032 llvm::Type::getInt32Ty(VMContext), 1))}; 1033 1034 getModule().addModuleFlag(llvm::Module::Require, 1035 "StrictVTablePointersRequirement", 1036 llvm::MDNode::get(VMContext, Ops)); 1037 } 1038 if (getModuleDebugInfo()) 1039 // We support a single version in the linked module. The LLVM 1040 // parser will drop debug info with a different version number 1041 // (and warn about it, too). 1042 getModule().addModuleFlag(llvm::Module::Warning, "Debug Info Version", 1043 llvm::DEBUG_METADATA_VERSION); 1044 1045 // We need to record the widths of enums and wchar_t, so that we can generate 1046 // the correct build attributes in the ARM backend. wchar_size is also used by 1047 // TargetLibraryInfo. 1048 uint64_t WCharWidth = 1049 Context.getTypeSizeInChars(Context.getWideCharType()).getQuantity(); 1050 getModule().addModuleFlag(llvm::Module::Error, "wchar_size", WCharWidth); 1051 1052 if (getTriple().isOSzOS()) { 1053 getModule().addModuleFlag(llvm::Module::Warning, 1054 "zos_product_major_version", 1055 uint32_t(CLANG_VERSION_MAJOR)); 1056 getModule().addModuleFlag(llvm::Module::Warning, 1057 "zos_product_minor_version", 1058 uint32_t(CLANG_VERSION_MINOR)); 1059 getModule().addModuleFlag(llvm::Module::Warning, "zos_product_patchlevel", 1060 uint32_t(CLANG_VERSION_PATCHLEVEL)); 1061 std::string ProductId = getClangVendor() + "clang"; 1062 getModule().addModuleFlag(llvm::Module::Error, "zos_product_id", 1063 llvm::MDString::get(VMContext, ProductId)); 1064 1065 // Record the language because we need it for the PPA2. 1066 StringRef lang_str = languageToString( 1067 LangStandard::getLangStandardForKind(LangOpts.LangStd).Language); 1068 getModule().addModuleFlag(llvm::Module::Error, "zos_cu_language", 1069 llvm::MDString::get(VMContext, lang_str)); 1070 1071 time_t TT = PreprocessorOpts.SourceDateEpoch 1072 ? *PreprocessorOpts.SourceDateEpoch 1073 : std::time(nullptr); 1074 getModule().addModuleFlag(llvm::Module::Max, "zos_translation_time", 1075 static_cast<uint64_t>(TT)); 1076 1077 // Multiple modes will be supported here. 1078 getModule().addModuleFlag(llvm::Module::Error, "zos_le_char_mode", 1079 llvm::MDString::get(VMContext, "ascii")); 1080 } 1081 1082 llvm::Triple T = Context.getTargetInfo().getTriple(); 1083 if (T.isARM() || T.isThumb()) { 1084 // The minimum width of an enum in bytes 1085 uint64_t EnumWidth = Context.getLangOpts().ShortEnums ? 1 : 4; 1086 getModule().addModuleFlag(llvm::Module::Error, "min_enum_size", EnumWidth); 1087 } 1088 1089 if (T.isRISCV()) { 1090 StringRef ABIStr = Target.getABI(); 1091 llvm::LLVMContext &Ctx = TheModule.getContext(); 1092 getModule().addModuleFlag(llvm::Module::Error, "target-abi", 1093 llvm::MDString::get(Ctx, ABIStr)); 1094 1095 // Add the canonical ISA string as metadata so the backend can set the ELF 1096 // attributes correctly. We use AppendUnique so LTO will keep all of the 1097 // unique ISA strings that were linked together. 1098 const std::vector<std::string> &Features = 1099 getTarget().getTargetOpts().Features; 1100 auto ParseResult = 1101 llvm::RISCVISAInfo::parseFeatures(T.isRISCV64() ? 64 : 32, Features); 1102 if (!errorToBool(ParseResult.takeError())) 1103 getModule().addModuleFlag( 1104 llvm::Module::AppendUnique, "riscv-isa", 1105 llvm::MDNode::get( 1106 Ctx, llvm::MDString::get(Ctx, (*ParseResult)->toString()))); 1107 } 1108 1109 if (CodeGenOpts.SanitizeCfiCrossDso) { 1110 // Indicate that we want cross-DSO control flow integrity checks. 1111 getModule().addModuleFlag(llvm::Module::Override, "Cross-DSO CFI", 1); 1112 } 1113 1114 if (CodeGenOpts.WholeProgramVTables) { 1115 // Indicate whether VFE was enabled for this module, so that the 1116 // vcall_visibility metadata added under whole program vtables is handled 1117 // appropriately in the optimizer. 1118 getModule().addModuleFlag(llvm::Module::Error, "Virtual Function Elim", 1119 CodeGenOpts.VirtualFunctionElimination); 1120 } 1121 1122 if (LangOpts.Sanitize.has(SanitizerKind::CFIICall)) { 1123 getModule().addModuleFlag(llvm::Module::Override, 1124 "CFI Canonical Jump Tables", 1125 CodeGenOpts.SanitizeCfiCanonicalJumpTables); 1126 } 1127 1128 if (LangOpts.Sanitize.has(SanitizerKind::KCFI)) { 1129 getModule().addModuleFlag(llvm::Module::Override, "kcfi", 1); 1130 // KCFI assumes patchable-function-prefix is the same for all indirectly 1131 // called functions. Store the expected offset for code generation. 1132 if (CodeGenOpts.PatchableFunctionEntryOffset) 1133 getModule().addModuleFlag(llvm::Module::Override, "kcfi-offset", 1134 CodeGenOpts.PatchableFunctionEntryOffset); 1135 } 1136 1137 if (CodeGenOpts.CFProtectionReturn && 1138 Target.checkCFProtectionReturnSupported(getDiags())) { 1139 // Indicate that we want to instrument return control flow protection. 1140 getModule().addModuleFlag(llvm::Module::Min, "cf-protection-return", 1141 1); 1142 } 1143 1144 if (CodeGenOpts.CFProtectionBranch && 1145 Target.checkCFProtectionBranchSupported(getDiags())) { 1146 // Indicate that we want to instrument branch control flow protection. 1147 getModule().addModuleFlag(llvm::Module::Min, "cf-protection-branch", 1148 1); 1149 } 1150 1151 if (CodeGenOpts.FunctionReturnThunks) 1152 getModule().addModuleFlag(llvm::Module::Override, "function_return_thunk_extern", 1); 1153 1154 if (CodeGenOpts.IndirectBranchCSPrefix) 1155 getModule().addModuleFlag(llvm::Module::Override, "indirect_branch_cs_prefix", 1); 1156 1157 // Add module metadata for return address signing (ignoring 1158 // non-leaf/all) and stack tagging. These are actually turned on by function 1159 // attributes, but we use module metadata to emit build attributes. This is 1160 // needed for LTO, where the function attributes are inside bitcode 1161 // serialised into a global variable by the time build attributes are 1162 // emitted, so we can't access them. LTO objects could be compiled with 1163 // different flags therefore module flags are set to "Min" behavior to achieve 1164 // the same end result of the normal build where e.g BTI is off if any object 1165 // doesn't support it. 1166 if (Context.getTargetInfo().hasFeature("ptrauth") && 1167 LangOpts.getSignReturnAddressScope() != 1168 LangOptions::SignReturnAddressScopeKind::None) 1169 getModule().addModuleFlag(llvm::Module::Override, 1170 "sign-return-address-buildattr", 1); 1171 if (LangOpts.Sanitize.has(SanitizerKind::MemtagStack)) 1172 getModule().addModuleFlag(llvm::Module::Override, 1173 "tag-stack-memory-buildattr", 1); 1174 1175 if (T.isARM() || T.isThumb() || T.isAArch64()) { 1176 if (LangOpts.BranchTargetEnforcement) 1177 getModule().addModuleFlag(llvm::Module::Min, "branch-target-enforcement", 1178 1); 1179 if (LangOpts.BranchProtectionPAuthLR) 1180 getModule().addModuleFlag(llvm::Module::Min, "branch-protection-pauth-lr", 1181 1); 1182 if (LangOpts.GuardedControlStack) 1183 getModule().addModuleFlag(llvm::Module::Min, "guarded-control-stack", 1); 1184 if (LangOpts.hasSignReturnAddress()) 1185 getModule().addModuleFlag(llvm::Module::Min, "sign-return-address", 1); 1186 if (LangOpts.isSignReturnAddressScopeAll()) 1187 getModule().addModuleFlag(llvm::Module::Min, "sign-return-address-all", 1188 1); 1189 if (!LangOpts.isSignReturnAddressWithAKey()) 1190 getModule().addModuleFlag(llvm::Module::Min, 1191 "sign-return-address-with-bkey", 1); 1192 } 1193 1194 if (CodeGenOpts.StackClashProtector) 1195 getModule().addModuleFlag( 1196 llvm::Module::Override, "probe-stack", 1197 llvm::MDString::get(TheModule.getContext(), "inline-asm")); 1198 1199 if (CodeGenOpts.StackProbeSize && CodeGenOpts.StackProbeSize != 4096) 1200 getModule().addModuleFlag(llvm::Module::Min, "stack-probe-size", 1201 CodeGenOpts.StackProbeSize); 1202 1203 if (!CodeGenOpts.MemoryProfileOutput.empty()) { 1204 llvm::LLVMContext &Ctx = TheModule.getContext(); 1205 getModule().addModuleFlag( 1206 llvm::Module::Error, "MemProfProfileFilename", 1207 llvm::MDString::get(Ctx, CodeGenOpts.MemoryProfileOutput)); 1208 } 1209 1210 if (LangOpts.CUDAIsDevice && getTriple().isNVPTX()) { 1211 // Indicate whether __nvvm_reflect should be configured to flush denormal 1212 // floating point values to 0. (This corresponds to its "__CUDA_FTZ" 1213 // property.) 1214 getModule().addModuleFlag(llvm::Module::Override, "nvvm-reflect-ftz", 1215 CodeGenOpts.FP32DenormalMode.Output != 1216 llvm::DenormalMode::IEEE); 1217 } 1218 1219 if (LangOpts.EHAsynch) 1220 getModule().addModuleFlag(llvm::Module::Warning, "eh-asynch", 1); 1221 1222 // Indicate whether this Module was compiled with -fopenmp 1223 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd) 1224 getModule().addModuleFlag(llvm::Module::Max, "openmp", LangOpts.OpenMP); 1225 if (getLangOpts().OpenMPIsTargetDevice) 1226 getModule().addModuleFlag(llvm::Module::Max, "openmp-device", 1227 LangOpts.OpenMP); 1228 1229 // Emit OpenCL specific module metadata: OpenCL/SPIR version. 1230 if (LangOpts.OpenCL || (LangOpts.CUDAIsDevice && getTriple().isSPIRV())) { 1231 EmitOpenCLMetadata(); 1232 // Emit SPIR version. 1233 if (getTriple().isSPIR()) { 1234 // SPIR v2.0 s2.12 - The SPIR version used by the module is stored in the 1235 // opencl.spir.version named metadata. 1236 // C++ for OpenCL has a distinct mapping for version compatibility with 1237 // OpenCL. 1238 auto Version = LangOpts.getOpenCLCompatibleVersion(); 1239 llvm::Metadata *SPIRVerElts[] = { 1240 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 1241 Int32Ty, Version / 100)), 1242 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 1243 Int32Ty, (Version / 100 > 1) ? 0 : 2))}; 1244 llvm::NamedMDNode *SPIRVerMD = 1245 TheModule.getOrInsertNamedMetadata("opencl.spir.version"); 1246 llvm::LLVMContext &Ctx = TheModule.getContext(); 1247 SPIRVerMD->addOperand(llvm::MDNode::get(Ctx, SPIRVerElts)); 1248 } 1249 } 1250 1251 // HLSL related end of code gen work items. 1252 if (LangOpts.HLSL) 1253 getHLSLRuntime().finishCodeGen(); 1254 1255 if (uint32_t PLevel = Context.getLangOpts().PICLevel) { 1256 assert(PLevel < 3 && "Invalid PIC Level"); 1257 getModule().setPICLevel(static_cast<llvm::PICLevel::Level>(PLevel)); 1258 if (Context.getLangOpts().PIE) 1259 getModule().setPIELevel(static_cast<llvm::PIELevel::Level>(PLevel)); 1260 } 1261 1262 if (getCodeGenOpts().CodeModel.size() > 0) { 1263 unsigned CM = llvm::StringSwitch<unsigned>(getCodeGenOpts().CodeModel) 1264 .Case("tiny", llvm::CodeModel::Tiny) 1265 .Case("small", llvm::CodeModel::Small) 1266 .Case("kernel", llvm::CodeModel::Kernel) 1267 .Case("medium", llvm::CodeModel::Medium) 1268 .Case("large", llvm::CodeModel::Large) 1269 .Default(~0u); 1270 if (CM != ~0u) { 1271 llvm::CodeModel::Model codeModel = static_cast<llvm::CodeModel::Model>(CM); 1272 getModule().setCodeModel(codeModel); 1273 1274 if ((CM == llvm::CodeModel::Medium || CM == llvm::CodeModel::Large) && 1275 Context.getTargetInfo().getTriple().getArch() == 1276 llvm::Triple::x86_64) { 1277 getModule().setLargeDataThreshold(getCodeGenOpts().LargeDataThreshold); 1278 } 1279 } 1280 } 1281 1282 if (CodeGenOpts.NoPLT) 1283 getModule().setRtLibUseGOT(); 1284 if (getTriple().isOSBinFormatELF() && 1285 CodeGenOpts.DirectAccessExternalData != 1286 getModule().getDirectAccessExternalData()) { 1287 getModule().setDirectAccessExternalData( 1288 CodeGenOpts.DirectAccessExternalData); 1289 } 1290 if (CodeGenOpts.UnwindTables) 1291 getModule().setUwtable(llvm::UWTableKind(CodeGenOpts.UnwindTables)); 1292 1293 switch (CodeGenOpts.getFramePointer()) { 1294 case CodeGenOptions::FramePointerKind::None: 1295 // 0 ("none") is the default. 1296 break; 1297 case CodeGenOptions::FramePointerKind::NonLeaf: 1298 getModule().setFramePointer(llvm::FramePointerKind::NonLeaf); 1299 break; 1300 case CodeGenOptions::FramePointerKind::All: 1301 getModule().setFramePointer(llvm::FramePointerKind::All); 1302 break; 1303 } 1304 1305 SimplifyPersonality(); 1306 1307 if (getCodeGenOpts().EmitDeclMetadata) 1308 EmitDeclMetadata(); 1309 1310 if (getCodeGenOpts().CoverageNotesFile.size() || 1311 getCodeGenOpts().CoverageDataFile.size()) 1312 EmitCoverageFile(); 1313 1314 if (CGDebugInfo *DI = getModuleDebugInfo()) 1315 DI->finalize(); 1316 1317 if (getCodeGenOpts().EmitVersionIdentMetadata) 1318 EmitVersionIdentMetadata(); 1319 1320 if (!getCodeGenOpts().RecordCommandLine.empty()) 1321 EmitCommandLineMetadata(); 1322 1323 if (!getCodeGenOpts().StackProtectorGuard.empty()) 1324 getModule().setStackProtectorGuard(getCodeGenOpts().StackProtectorGuard); 1325 if (!getCodeGenOpts().StackProtectorGuardReg.empty()) 1326 getModule().setStackProtectorGuardReg( 1327 getCodeGenOpts().StackProtectorGuardReg); 1328 if (!getCodeGenOpts().StackProtectorGuardSymbol.empty()) 1329 getModule().setStackProtectorGuardSymbol( 1330 getCodeGenOpts().StackProtectorGuardSymbol); 1331 if (getCodeGenOpts().StackProtectorGuardOffset != INT_MAX) 1332 getModule().setStackProtectorGuardOffset( 1333 getCodeGenOpts().StackProtectorGuardOffset); 1334 if (getCodeGenOpts().StackAlignment) 1335 getModule().setOverrideStackAlignment(getCodeGenOpts().StackAlignment); 1336 if (getCodeGenOpts().SkipRaxSetup) 1337 getModule().addModuleFlag(llvm::Module::Override, "SkipRaxSetup", 1); 1338 if (getLangOpts().RegCall4) 1339 getModule().addModuleFlag(llvm::Module::Override, "RegCallv4", 1); 1340 1341 if (getContext().getTargetInfo().getMaxTLSAlign()) 1342 getModule().addModuleFlag(llvm::Module::Error, "MaxTLSAlign", 1343 getContext().getTargetInfo().getMaxTLSAlign()); 1344 1345 getTargetCodeGenInfo().emitTargetGlobals(*this); 1346 1347 getTargetCodeGenInfo().emitTargetMetadata(*this, MangledDeclNames); 1348 1349 EmitBackendOptionsMetadata(getCodeGenOpts()); 1350 1351 // If there is device offloading code embed it in the host now. 1352 EmbedObject(&getModule(), CodeGenOpts, getDiags()); 1353 1354 // Set visibility from DLL storage class 1355 // We do this at the end of LLVM IR generation; after any operation 1356 // that might affect the DLL storage class or the visibility, and 1357 // before anything that might act on these. 1358 setVisibilityFromDLLStorageClass(LangOpts, getModule()); 1359 } 1360 1361 void CodeGenModule::EmitOpenCLMetadata() { 1362 // SPIR v2.0 s2.13 - The OpenCL version used by the module is stored in the 1363 // opencl.ocl.version named metadata node. 1364 // C++ for OpenCL has a distinct mapping for versions compatibile with OpenCL. 1365 auto Version = LangOpts.getOpenCLCompatibleVersion(); 1366 llvm::Metadata *OCLVerElts[] = { 1367 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 1368 Int32Ty, Version / 100)), 1369 llvm::ConstantAsMetadata::get(llvm::ConstantInt::get( 1370 Int32Ty, (Version % 100) / 10))}; 1371 llvm::NamedMDNode *OCLVerMD = 1372 TheModule.getOrInsertNamedMetadata("opencl.ocl.version"); 1373 llvm::LLVMContext &Ctx = TheModule.getContext(); 1374 OCLVerMD->addOperand(llvm::MDNode::get(Ctx, OCLVerElts)); 1375 } 1376 1377 void CodeGenModule::EmitBackendOptionsMetadata( 1378 const CodeGenOptions &CodeGenOpts) { 1379 if (getTriple().isRISCV()) { 1380 getModule().addModuleFlag(llvm::Module::Min, "SmallDataLimit", 1381 CodeGenOpts.SmallDataLimit); 1382 } 1383 } 1384 1385 void CodeGenModule::UpdateCompletedType(const TagDecl *TD) { 1386 // Make sure that this type is translated. 1387 Types.UpdateCompletedType(TD); 1388 } 1389 1390 void CodeGenModule::RefreshTypeCacheForClass(const CXXRecordDecl *RD) { 1391 // Make sure that this type is translated. 1392 Types.RefreshTypeCacheForClass(RD); 1393 } 1394 1395 llvm::MDNode *CodeGenModule::getTBAATypeInfo(QualType QTy) { 1396 if (!TBAA) 1397 return nullptr; 1398 return TBAA->getTypeInfo(QTy); 1399 } 1400 1401 TBAAAccessInfo CodeGenModule::getTBAAAccessInfo(QualType AccessType) { 1402 if (!TBAA) 1403 return TBAAAccessInfo(); 1404 if (getLangOpts().CUDAIsDevice) { 1405 // As CUDA builtin surface/texture types are replaced, skip generating TBAA 1406 // access info. 1407 if (AccessType->isCUDADeviceBuiltinSurfaceType()) { 1408 if (getTargetCodeGenInfo().getCUDADeviceBuiltinSurfaceDeviceType() != 1409 nullptr) 1410 return TBAAAccessInfo(); 1411 } else if (AccessType->isCUDADeviceBuiltinTextureType()) { 1412 if (getTargetCodeGenInfo().getCUDADeviceBuiltinTextureDeviceType() != 1413 nullptr) 1414 return TBAAAccessInfo(); 1415 } 1416 } 1417 return TBAA->getAccessInfo(AccessType); 1418 } 1419 1420 TBAAAccessInfo 1421 CodeGenModule::getTBAAVTablePtrAccessInfo(llvm::Type *VTablePtrType) { 1422 if (!TBAA) 1423 return TBAAAccessInfo(); 1424 return TBAA->getVTablePtrAccessInfo(VTablePtrType); 1425 } 1426 1427 llvm::MDNode *CodeGenModule::getTBAAStructInfo(QualType QTy) { 1428 if (!TBAA) 1429 return nullptr; 1430 return TBAA->getTBAAStructInfo(QTy); 1431 } 1432 1433 llvm::MDNode *CodeGenModule::getTBAABaseTypeInfo(QualType QTy) { 1434 if (!TBAA) 1435 return nullptr; 1436 return TBAA->getBaseTypeInfo(QTy); 1437 } 1438 1439 llvm::MDNode *CodeGenModule::getTBAAAccessTagInfo(TBAAAccessInfo Info) { 1440 if (!TBAA) 1441 return nullptr; 1442 return TBAA->getAccessTagInfo(Info); 1443 } 1444 1445 TBAAAccessInfo CodeGenModule::mergeTBAAInfoForCast(TBAAAccessInfo SourceInfo, 1446 TBAAAccessInfo TargetInfo) { 1447 if (!TBAA) 1448 return TBAAAccessInfo(); 1449 return TBAA->mergeTBAAInfoForCast(SourceInfo, TargetInfo); 1450 } 1451 1452 TBAAAccessInfo 1453 CodeGenModule::mergeTBAAInfoForConditionalOperator(TBAAAccessInfo InfoA, 1454 TBAAAccessInfo InfoB) { 1455 if (!TBAA) 1456 return TBAAAccessInfo(); 1457 return TBAA->mergeTBAAInfoForConditionalOperator(InfoA, InfoB); 1458 } 1459 1460 TBAAAccessInfo 1461 CodeGenModule::mergeTBAAInfoForMemoryTransfer(TBAAAccessInfo DestInfo, 1462 TBAAAccessInfo SrcInfo) { 1463 if (!TBAA) 1464 return TBAAAccessInfo(); 1465 return TBAA->mergeTBAAInfoForConditionalOperator(DestInfo, SrcInfo); 1466 } 1467 1468 void CodeGenModule::DecorateInstructionWithTBAA(llvm::Instruction *Inst, 1469 TBAAAccessInfo TBAAInfo) { 1470 if (llvm::MDNode *Tag = getTBAAAccessTagInfo(TBAAInfo)) 1471 Inst->setMetadata(llvm::LLVMContext::MD_tbaa, Tag); 1472 } 1473 1474 void CodeGenModule::DecorateInstructionWithInvariantGroup( 1475 llvm::Instruction *I, const CXXRecordDecl *RD) { 1476 I->setMetadata(llvm::LLVMContext::MD_invariant_group, 1477 llvm::MDNode::get(getLLVMContext(), {})); 1478 } 1479 1480 void CodeGenModule::Error(SourceLocation loc, StringRef message) { 1481 unsigned diagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, "%0"); 1482 getDiags().Report(Context.getFullLoc(loc), diagID) << message; 1483 } 1484 1485 /// ErrorUnsupported - Print out an error that codegen doesn't support the 1486 /// specified stmt yet. 1487 void CodeGenModule::ErrorUnsupported(const Stmt *S, const char *Type) { 1488 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, 1489 "cannot compile this %0 yet"); 1490 std::string Msg = Type; 1491 getDiags().Report(Context.getFullLoc(S->getBeginLoc()), DiagID) 1492 << Msg << S->getSourceRange(); 1493 } 1494 1495 /// ErrorUnsupported - Print out an error that codegen doesn't support the 1496 /// specified decl yet. 1497 void CodeGenModule::ErrorUnsupported(const Decl *D, const char *Type) { 1498 unsigned DiagID = getDiags().getCustomDiagID(DiagnosticsEngine::Error, 1499 "cannot compile this %0 yet"); 1500 std::string Msg = Type; 1501 getDiags().Report(Context.getFullLoc(D->getLocation()), DiagID) << Msg; 1502 } 1503 1504 llvm::ConstantInt *CodeGenModule::getSize(CharUnits size) { 1505 return llvm::ConstantInt::get(SizeTy, size.getQuantity()); 1506 } 1507 1508 void CodeGenModule::setGlobalVisibility(llvm::GlobalValue *GV, 1509 const NamedDecl *D) const { 1510 // Internal definitions always have default visibility. 1511 if (GV->hasLocalLinkage()) { 1512 GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 1513 return; 1514 } 1515 if (!D) 1516 return; 1517 1518 // Set visibility for definitions, and for declarations if requested globally 1519 // or set explicitly. 1520 LinkageInfo LV = D->getLinkageAndVisibility(); 1521 1522 // OpenMP declare target variables must be visible to the host so they can 1523 // be registered. We require protected visibility unless the variable has 1524 // the DT_nohost modifier and does not need to be registered. 1525 if (Context.getLangOpts().OpenMP && 1526 Context.getLangOpts().OpenMPIsTargetDevice && isa<VarDecl>(D) && 1527 D->hasAttr<OMPDeclareTargetDeclAttr>() && 1528 D->getAttr<OMPDeclareTargetDeclAttr>()->getDevType() != 1529 OMPDeclareTargetDeclAttr::DT_NoHost && 1530 LV.getVisibility() == HiddenVisibility) { 1531 GV->setVisibility(llvm::GlobalValue::ProtectedVisibility); 1532 return; 1533 } 1534 1535 if (GV->hasDLLExportStorageClass() || GV->hasDLLImportStorageClass()) { 1536 // Reject incompatible dlllstorage and visibility annotations. 1537 if (!LV.isVisibilityExplicit()) 1538 return; 1539 if (GV->hasDLLExportStorageClass()) { 1540 if (LV.getVisibility() == HiddenVisibility) 1541 getDiags().Report(D->getLocation(), 1542 diag::err_hidden_visibility_dllexport); 1543 } else if (LV.getVisibility() != DefaultVisibility) { 1544 getDiags().Report(D->getLocation(), 1545 diag::err_non_default_visibility_dllimport); 1546 } 1547 return; 1548 } 1549 1550 if (LV.isVisibilityExplicit() || getLangOpts().SetVisibilityForExternDecls || 1551 !GV->isDeclarationForLinker()) 1552 GV->setVisibility(GetLLVMVisibility(LV.getVisibility())); 1553 } 1554 1555 static bool shouldAssumeDSOLocal(const CodeGenModule &CGM, 1556 llvm::GlobalValue *GV) { 1557 if (GV->hasLocalLinkage()) 1558 return true; 1559 1560 if (!GV->hasDefaultVisibility() && !GV->hasExternalWeakLinkage()) 1561 return true; 1562 1563 // DLLImport explicitly marks the GV as external. 1564 if (GV->hasDLLImportStorageClass()) 1565 return false; 1566 1567 const llvm::Triple &TT = CGM.getTriple(); 1568 const auto &CGOpts = CGM.getCodeGenOpts(); 1569 if (TT.isWindowsGNUEnvironment()) { 1570 // In MinGW, variables without DLLImport can still be automatically 1571 // imported from a DLL by the linker; don't mark variables that 1572 // potentially could come from another DLL as DSO local. 1573 1574 // With EmulatedTLS, TLS variables can be autoimported from other DLLs 1575 // (and this actually happens in the public interface of libstdc++), so 1576 // such variables can't be marked as DSO local. (Native TLS variables 1577 // can't be dllimported at all, though.) 1578 if (GV->isDeclarationForLinker() && isa<llvm::GlobalVariable>(GV) && 1579 (!GV->isThreadLocal() || CGM.getCodeGenOpts().EmulatedTLS) && 1580 CGOpts.AutoImport) 1581 return false; 1582 } 1583 1584 // On COFF, don't mark 'extern_weak' symbols as DSO local. If these symbols 1585 // remain unresolved in the link, they can be resolved to zero, which is 1586 // outside the current DSO. 1587 if (TT.isOSBinFormatCOFF() && GV->hasExternalWeakLinkage()) 1588 return false; 1589 1590 // Every other GV is local on COFF. 1591 // Make an exception for windows OS in the triple: Some firmware builds use 1592 // *-win32-macho triples. This (accidentally?) produced windows relocations 1593 // without GOT tables in older clang versions; Keep this behaviour. 1594 // FIXME: even thread local variables? 1595 if (TT.isOSBinFormatCOFF() || (TT.isOSWindows() && TT.isOSBinFormatMachO())) 1596 return true; 1597 1598 // Only handle COFF and ELF for now. 1599 if (!TT.isOSBinFormatELF()) 1600 return false; 1601 1602 // If this is not an executable, don't assume anything is local. 1603 llvm::Reloc::Model RM = CGOpts.RelocationModel; 1604 const auto &LOpts = CGM.getLangOpts(); 1605 if (RM != llvm::Reloc::Static && !LOpts.PIE) { 1606 // On ELF, if -fno-semantic-interposition is specified and the target 1607 // supports local aliases, there will be neither CC1 1608 // -fsemantic-interposition nor -fhalf-no-semantic-interposition. Set 1609 // dso_local on the function if using a local alias is preferable (can avoid 1610 // PLT indirection). 1611 if (!(isa<llvm::Function>(GV) && GV->canBenefitFromLocalAlias())) 1612 return false; 1613 return !(CGM.getLangOpts().SemanticInterposition || 1614 CGM.getLangOpts().HalfNoSemanticInterposition); 1615 } 1616 1617 // A definition cannot be preempted from an executable. 1618 if (!GV->isDeclarationForLinker()) 1619 return true; 1620 1621 // Most PIC code sequences that assume that a symbol is local cannot produce a 1622 // 0 if it turns out the symbol is undefined. While this is ABI and relocation 1623 // depended, it seems worth it to handle it here. 1624 if (RM == llvm::Reloc::PIC_ && GV->hasExternalWeakLinkage()) 1625 return false; 1626 1627 // PowerPC64 prefers TOC indirection to avoid copy relocations. 1628 if (TT.isPPC64()) 1629 return false; 1630 1631 if (CGOpts.DirectAccessExternalData) { 1632 // If -fdirect-access-external-data (default for -fno-pic), set dso_local 1633 // for non-thread-local variables. If the symbol is not defined in the 1634 // executable, a copy relocation will be needed at link time. dso_local is 1635 // excluded for thread-local variables because they generally don't support 1636 // copy relocations. 1637 if (auto *Var = dyn_cast<llvm::GlobalVariable>(GV)) 1638 if (!Var->isThreadLocal()) 1639 return true; 1640 1641 // -fno-pic sets dso_local on a function declaration to allow direct 1642 // accesses when taking its address (similar to a data symbol). If the 1643 // function is not defined in the executable, a canonical PLT entry will be 1644 // needed at link time. -fno-direct-access-external-data can avoid the 1645 // canonical PLT entry. We don't generalize this condition to -fpie/-fpic as 1646 // it could just cause trouble without providing perceptible benefits. 1647 if (isa<llvm::Function>(GV) && !CGOpts.NoPLT && RM == llvm::Reloc::Static) 1648 return true; 1649 } 1650 1651 // If we can use copy relocations we can assume it is local. 1652 1653 // Otherwise don't assume it is local. 1654 return false; 1655 } 1656 1657 void CodeGenModule::setDSOLocal(llvm::GlobalValue *GV) const { 1658 GV->setDSOLocal(shouldAssumeDSOLocal(*this, GV)); 1659 } 1660 1661 void CodeGenModule::setDLLImportDLLExport(llvm::GlobalValue *GV, 1662 GlobalDecl GD) const { 1663 const auto *D = dyn_cast<NamedDecl>(GD.getDecl()); 1664 // C++ destructors have a few C++ ABI specific special cases. 1665 if (const auto *Dtor = dyn_cast_or_null<CXXDestructorDecl>(D)) { 1666 getCXXABI().setCXXDestructorDLLStorage(GV, Dtor, GD.getDtorType()); 1667 return; 1668 } 1669 setDLLImportDLLExport(GV, D); 1670 } 1671 1672 void CodeGenModule::setDLLImportDLLExport(llvm::GlobalValue *GV, 1673 const NamedDecl *D) const { 1674 if (D && D->isExternallyVisible()) { 1675 if (D->hasAttr<DLLImportAttr>()) 1676 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass); 1677 else if ((D->hasAttr<DLLExportAttr>() || 1678 shouldMapVisibilityToDLLExport(D)) && 1679 !GV->isDeclarationForLinker()) 1680 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass); 1681 } 1682 } 1683 1684 void CodeGenModule::setGVProperties(llvm::GlobalValue *GV, 1685 GlobalDecl GD) const { 1686 setDLLImportDLLExport(GV, GD); 1687 setGVPropertiesAux(GV, dyn_cast<NamedDecl>(GD.getDecl())); 1688 } 1689 1690 void CodeGenModule::setGVProperties(llvm::GlobalValue *GV, 1691 const NamedDecl *D) const { 1692 setDLLImportDLLExport(GV, D); 1693 setGVPropertiesAux(GV, D); 1694 } 1695 1696 void CodeGenModule::setGVPropertiesAux(llvm::GlobalValue *GV, 1697 const NamedDecl *D) const { 1698 setGlobalVisibility(GV, D); 1699 setDSOLocal(GV); 1700 GV->setPartition(CodeGenOpts.SymbolPartition); 1701 } 1702 1703 static llvm::GlobalVariable::ThreadLocalMode GetLLVMTLSModel(StringRef S) { 1704 return llvm::StringSwitch<llvm::GlobalVariable::ThreadLocalMode>(S) 1705 .Case("global-dynamic", llvm::GlobalVariable::GeneralDynamicTLSModel) 1706 .Case("local-dynamic", llvm::GlobalVariable::LocalDynamicTLSModel) 1707 .Case("initial-exec", llvm::GlobalVariable::InitialExecTLSModel) 1708 .Case("local-exec", llvm::GlobalVariable::LocalExecTLSModel); 1709 } 1710 1711 llvm::GlobalVariable::ThreadLocalMode 1712 CodeGenModule::GetDefaultLLVMTLSModel() const { 1713 switch (CodeGenOpts.getDefaultTLSModel()) { 1714 case CodeGenOptions::GeneralDynamicTLSModel: 1715 return llvm::GlobalVariable::GeneralDynamicTLSModel; 1716 case CodeGenOptions::LocalDynamicTLSModel: 1717 return llvm::GlobalVariable::LocalDynamicTLSModel; 1718 case CodeGenOptions::InitialExecTLSModel: 1719 return llvm::GlobalVariable::InitialExecTLSModel; 1720 case CodeGenOptions::LocalExecTLSModel: 1721 return llvm::GlobalVariable::LocalExecTLSModel; 1722 } 1723 llvm_unreachable("Invalid TLS model!"); 1724 } 1725 1726 void CodeGenModule::setTLSMode(llvm::GlobalValue *GV, const VarDecl &D) const { 1727 assert(D.getTLSKind() && "setting TLS mode on non-TLS var!"); 1728 1729 llvm::GlobalValue::ThreadLocalMode TLM; 1730 TLM = GetDefaultLLVMTLSModel(); 1731 1732 // Override the TLS model if it is explicitly specified. 1733 if (const TLSModelAttr *Attr = D.getAttr<TLSModelAttr>()) { 1734 TLM = GetLLVMTLSModel(Attr->getModel()); 1735 } 1736 1737 GV->setThreadLocalMode(TLM); 1738 } 1739 1740 static std::string getCPUSpecificMangling(const CodeGenModule &CGM, 1741 StringRef Name) { 1742 const TargetInfo &Target = CGM.getTarget(); 1743 return (Twine('.') + Twine(Target.CPUSpecificManglingCharacter(Name))).str(); 1744 } 1745 1746 static void AppendCPUSpecificCPUDispatchMangling(const CodeGenModule &CGM, 1747 const CPUSpecificAttr *Attr, 1748 unsigned CPUIndex, 1749 raw_ostream &Out) { 1750 // cpu_specific gets the current name, dispatch gets the resolver if IFunc is 1751 // supported. 1752 if (Attr) 1753 Out << getCPUSpecificMangling(CGM, Attr->getCPUName(CPUIndex)->getName()); 1754 else if (CGM.getTarget().supportsIFunc()) 1755 Out << ".resolver"; 1756 } 1757 1758 // Returns true if GD is a function decl with internal linkage and 1759 // needs a unique suffix after the mangled name. 1760 static bool isUniqueInternalLinkageDecl(GlobalDecl GD, 1761 CodeGenModule &CGM) { 1762 const Decl *D = GD.getDecl(); 1763 return !CGM.getModuleNameHash().empty() && isa<FunctionDecl>(D) && 1764 (CGM.getFunctionLinkage(GD) == llvm::GlobalValue::InternalLinkage); 1765 } 1766 1767 static std::string getMangledNameImpl(CodeGenModule &CGM, GlobalDecl GD, 1768 const NamedDecl *ND, 1769 bool OmitMultiVersionMangling = false) { 1770 SmallString<256> Buffer; 1771 llvm::raw_svector_ostream Out(Buffer); 1772 MangleContext &MC = CGM.getCXXABI().getMangleContext(); 1773 if (!CGM.getModuleNameHash().empty()) 1774 MC.needsUniqueInternalLinkageNames(); 1775 bool ShouldMangle = MC.shouldMangleDeclName(ND); 1776 if (ShouldMangle) 1777 MC.mangleName(GD.getWithDecl(ND), Out); 1778 else { 1779 IdentifierInfo *II = ND->getIdentifier(); 1780 assert(II && "Attempt to mangle unnamed decl."); 1781 const auto *FD = dyn_cast<FunctionDecl>(ND); 1782 1783 if (FD && 1784 FD->getType()->castAs<FunctionType>()->getCallConv() == CC_X86RegCall) { 1785 if (CGM.getLangOpts().RegCall4) 1786 Out << "__regcall4__" << II->getName(); 1787 else 1788 Out << "__regcall3__" << II->getName(); 1789 } else if (FD && FD->hasAttr<CUDAGlobalAttr>() && 1790 GD.getKernelReferenceKind() == KernelReferenceKind::Stub) { 1791 Out << "__device_stub__" << II->getName(); 1792 } else { 1793 Out << II->getName(); 1794 } 1795 } 1796 1797 // Check if the module name hash should be appended for internal linkage 1798 // symbols. This should come before multi-version target suffixes are 1799 // appended. This is to keep the name and module hash suffix of the 1800 // internal linkage function together. The unique suffix should only be 1801 // added when name mangling is done to make sure that the final name can 1802 // be properly demangled. For example, for C functions without prototypes, 1803 // name mangling is not done and the unique suffix should not be appeneded 1804 // then. 1805 if (ShouldMangle && isUniqueInternalLinkageDecl(GD, CGM)) { 1806 assert(CGM.getCodeGenOpts().UniqueInternalLinkageNames && 1807 "Hash computed when not explicitly requested"); 1808 Out << CGM.getModuleNameHash(); 1809 } 1810 1811 if (const auto *FD = dyn_cast<FunctionDecl>(ND)) 1812 if (FD->isMultiVersion() && !OmitMultiVersionMangling) { 1813 switch (FD->getMultiVersionKind()) { 1814 case MultiVersionKind::CPUDispatch: 1815 case MultiVersionKind::CPUSpecific: 1816 AppendCPUSpecificCPUDispatchMangling(CGM, 1817 FD->getAttr<CPUSpecificAttr>(), 1818 GD.getMultiVersionIndex(), Out); 1819 break; 1820 case MultiVersionKind::Target: { 1821 auto *Attr = FD->getAttr<TargetAttr>(); 1822 const ABIInfo &Info = CGM.getTargetCodeGenInfo().getABIInfo(); 1823 Info.appendAttributeMangling(Attr, Out); 1824 break; 1825 } 1826 case MultiVersionKind::TargetVersion: { 1827 auto *Attr = FD->getAttr<TargetVersionAttr>(); 1828 const ABIInfo &Info = CGM.getTargetCodeGenInfo().getABIInfo(); 1829 Info.appendAttributeMangling(Attr, Out); 1830 break; 1831 } 1832 case MultiVersionKind::TargetClones: { 1833 auto *Attr = FD->getAttr<TargetClonesAttr>(); 1834 unsigned Index = GD.getMultiVersionIndex(); 1835 const ABIInfo &Info = CGM.getTargetCodeGenInfo().getABIInfo(); 1836 Info.appendAttributeMangling(Attr, Index, Out); 1837 break; 1838 } 1839 case MultiVersionKind::None: 1840 llvm_unreachable("None multiversion type isn't valid here"); 1841 } 1842 } 1843 1844 // Make unique name for device side static file-scope variable for HIP. 1845 if (CGM.getContext().shouldExternalize(ND) && 1846 CGM.getLangOpts().GPURelocatableDeviceCode && 1847 CGM.getLangOpts().CUDAIsDevice) 1848 CGM.printPostfixForExternalizedDecl(Out, ND); 1849 1850 return std::string(Out.str()); 1851 } 1852 1853 void CodeGenModule::UpdateMultiVersionNames(GlobalDecl GD, 1854 const FunctionDecl *FD, 1855 StringRef &CurName) { 1856 if (!FD->isMultiVersion()) 1857 return; 1858 1859 // Get the name of what this would be without the 'target' attribute. This 1860 // allows us to lookup the version that was emitted when this wasn't a 1861 // multiversion function. 1862 std::string NonTargetName = 1863 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true); 1864 GlobalDecl OtherGD; 1865 if (lookupRepresentativeDecl(NonTargetName, OtherGD)) { 1866 assert(OtherGD.getCanonicalDecl() 1867 .getDecl() 1868 ->getAsFunction() 1869 ->isMultiVersion() && 1870 "Other GD should now be a multiversioned function"); 1871 // OtherFD is the version of this function that was mangled BEFORE 1872 // becoming a MultiVersion function. It potentially needs to be updated. 1873 const FunctionDecl *OtherFD = OtherGD.getCanonicalDecl() 1874 .getDecl() 1875 ->getAsFunction() 1876 ->getMostRecentDecl(); 1877 std::string OtherName = getMangledNameImpl(*this, OtherGD, OtherFD); 1878 // This is so that if the initial version was already the 'default' 1879 // version, we don't try to update it. 1880 if (OtherName != NonTargetName) { 1881 // Remove instead of erase, since others may have stored the StringRef 1882 // to this. 1883 const auto ExistingRecord = Manglings.find(NonTargetName); 1884 if (ExistingRecord != std::end(Manglings)) 1885 Manglings.remove(&(*ExistingRecord)); 1886 auto Result = Manglings.insert(std::make_pair(OtherName, OtherGD)); 1887 StringRef OtherNameRef = MangledDeclNames[OtherGD.getCanonicalDecl()] = 1888 Result.first->first(); 1889 // If this is the current decl is being created, make sure we update the name. 1890 if (GD.getCanonicalDecl() == OtherGD.getCanonicalDecl()) 1891 CurName = OtherNameRef; 1892 if (llvm::GlobalValue *Entry = GetGlobalValue(NonTargetName)) 1893 Entry->setName(OtherName); 1894 } 1895 } 1896 } 1897 1898 StringRef CodeGenModule::getMangledName(GlobalDecl GD) { 1899 GlobalDecl CanonicalGD = GD.getCanonicalDecl(); 1900 1901 // Some ABIs don't have constructor variants. Make sure that base and 1902 // complete constructors get mangled the same. 1903 if (const auto *CD = dyn_cast<CXXConstructorDecl>(CanonicalGD.getDecl())) { 1904 if (!getTarget().getCXXABI().hasConstructorVariants()) { 1905 CXXCtorType OrigCtorType = GD.getCtorType(); 1906 assert(OrigCtorType == Ctor_Base || OrigCtorType == Ctor_Complete); 1907 if (OrigCtorType == Ctor_Base) 1908 CanonicalGD = GlobalDecl(CD, Ctor_Complete); 1909 } 1910 } 1911 1912 // In CUDA/HIP device compilation with -fgpu-rdc, the mangled name of a 1913 // static device variable depends on whether the variable is referenced by 1914 // a host or device host function. Therefore the mangled name cannot be 1915 // cached. 1916 if (!LangOpts.CUDAIsDevice || !getContext().mayExternalize(GD.getDecl())) { 1917 auto FoundName = MangledDeclNames.find(CanonicalGD); 1918 if (FoundName != MangledDeclNames.end()) 1919 return FoundName->second; 1920 } 1921 1922 // Keep the first result in the case of a mangling collision. 1923 const auto *ND = cast<NamedDecl>(GD.getDecl()); 1924 std::string MangledName = getMangledNameImpl(*this, GD, ND); 1925 1926 // Ensure either we have different ABIs between host and device compilations, 1927 // says host compilation following MSVC ABI but device compilation follows 1928 // Itanium C++ ABI or, if they follow the same ABI, kernel names after 1929 // mangling should be the same after name stubbing. The later checking is 1930 // very important as the device kernel name being mangled in host-compilation 1931 // is used to resolve the device binaries to be executed. Inconsistent naming 1932 // result in undefined behavior. Even though we cannot check that naming 1933 // directly between host- and device-compilations, the host- and 1934 // device-mangling in host compilation could help catching certain ones. 1935 assert(!isa<FunctionDecl>(ND) || !ND->hasAttr<CUDAGlobalAttr>() || 1936 getContext().shouldExternalize(ND) || getLangOpts().CUDAIsDevice || 1937 (getContext().getAuxTargetInfo() && 1938 (getContext().getAuxTargetInfo()->getCXXABI() != 1939 getContext().getTargetInfo().getCXXABI())) || 1940 getCUDARuntime().getDeviceSideName(ND) == 1941 getMangledNameImpl( 1942 *this, 1943 GD.getWithKernelReferenceKind(KernelReferenceKind::Kernel), 1944 ND)); 1945 1946 auto Result = Manglings.insert(std::make_pair(MangledName, GD)); 1947 return MangledDeclNames[CanonicalGD] = Result.first->first(); 1948 } 1949 1950 StringRef CodeGenModule::getBlockMangledName(GlobalDecl GD, 1951 const BlockDecl *BD) { 1952 MangleContext &MangleCtx = getCXXABI().getMangleContext(); 1953 const Decl *D = GD.getDecl(); 1954 1955 SmallString<256> Buffer; 1956 llvm::raw_svector_ostream Out(Buffer); 1957 if (!D) 1958 MangleCtx.mangleGlobalBlock(BD, 1959 dyn_cast_or_null<VarDecl>(initializedGlobalDecl.getDecl()), Out); 1960 else if (const auto *CD = dyn_cast<CXXConstructorDecl>(D)) 1961 MangleCtx.mangleCtorBlock(CD, GD.getCtorType(), BD, Out); 1962 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(D)) 1963 MangleCtx.mangleDtorBlock(DD, GD.getDtorType(), BD, Out); 1964 else 1965 MangleCtx.mangleBlock(cast<DeclContext>(D), BD, Out); 1966 1967 auto Result = Manglings.insert(std::make_pair(Out.str(), BD)); 1968 return Result.first->first(); 1969 } 1970 1971 const GlobalDecl CodeGenModule::getMangledNameDecl(StringRef Name) { 1972 auto it = MangledDeclNames.begin(); 1973 while (it != MangledDeclNames.end()) { 1974 if (it->second == Name) 1975 return it->first; 1976 it++; 1977 } 1978 return GlobalDecl(); 1979 } 1980 1981 llvm::GlobalValue *CodeGenModule::GetGlobalValue(StringRef Name) { 1982 return getModule().getNamedValue(Name); 1983 } 1984 1985 /// AddGlobalCtor - Add a function to the list that will be called before 1986 /// main() runs. 1987 void CodeGenModule::AddGlobalCtor(llvm::Function *Ctor, int Priority, 1988 unsigned LexOrder, 1989 llvm::Constant *AssociatedData) { 1990 // FIXME: Type coercion of void()* types. 1991 GlobalCtors.push_back(Structor(Priority, LexOrder, Ctor, AssociatedData)); 1992 } 1993 1994 /// AddGlobalDtor - Add a function to the list that will be called 1995 /// when the module is unloaded. 1996 void CodeGenModule::AddGlobalDtor(llvm::Function *Dtor, int Priority, 1997 bool IsDtorAttrFunc) { 1998 if (CodeGenOpts.RegisterGlobalDtorsWithAtExit && 1999 (!getContext().getTargetInfo().getTriple().isOSAIX() || IsDtorAttrFunc)) { 2000 DtorsUsingAtExit[Priority].push_back(Dtor); 2001 return; 2002 } 2003 2004 // FIXME: Type coercion of void()* types. 2005 GlobalDtors.push_back(Structor(Priority, ~0U, Dtor, nullptr)); 2006 } 2007 2008 void CodeGenModule::EmitCtorList(CtorList &Fns, const char *GlobalName) { 2009 if (Fns.empty()) return; 2010 2011 // Ctor function type is void()*. 2012 llvm::FunctionType* CtorFTy = llvm::FunctionType::get(VoidTy, false); 2013 llvm::Type *CtorPFTy = llvm::PointerType::get(CtorFTy, 2014 TheModule.getDataLayout().getProgramAddressSpace()); 2015 2016 // Get the type of a ctor entry, { i32, void ()*, i8* }. 2017 llvm::StructType *CtorStructTy = llvm::StructType::get( 2018 Int32Ty, CtorPFTy, VoidPtrTy); 2019 2020 // Construct the constructor and destructor arrays. 2021 ConstantInitBuilder builder(*this); 2022 auto ctors = builder.beginArray(CtorStructTy); 2023 for (const auto &I : Fns) { 2024 auto ctor = ctors.beginStruct(CtorStructTy); 2025 ctor.addInt(Int32Ty, I.Priority); 2026 ctor.add(I.Initializer); 2027 if (I.AssociatedData) 2028 ctor.add(I.AssociatedData); 2029 else 2030 ctor.addNullPointer(VoidPtrTy); 2031 ctor.finishAndAddTo(ctors); 2032 } 2033 2034 auto list = 2035 ctors.finishAndCreateGlobal(GlobalName, getPointerAlign(), 2036 /*constant*/ false, 2037 llvm::GlobalValue::AppendingLinkage); 2038 2039 // The LTO linker doesn't seem to like it when we set an alignment 2040 // on appending variables. Take it off as a workaround. 2041 list->setAlignment(std::nullopt); 2042 2043 Fns.clear(); 2044 } 2045 2046 llvm::GlobalValue::LinkageTypes 2047 CodeGenModule::getFunctionLinkage(GlobalDecl GD) { 2048 const auto *D = cast<FunctionDecl>(GD.getDecl()); 2049 2050 GVALinkage Linkage = getContext().GetGVALinkageForFunction(D); 2051 2052 if (const auto *Dtor = dyn_cast<CXXDestructorDecl>(D)) 2053 return getCXXABI().getCXXDestructorLinkage(Linkage, Dtor, GD.getDtorType()); 2054 2055 return getLLVMLinkageForDeclarator(D, Linkage); 2056 } 2057 2058 llvm::ConstantInt *CodeGenModule::CreateCrossDsoCfiTypeId(llvm::Metadata *MD) { 2059 llvm::MDString *MDS = dyn_cast<llvm::MDString>(MD); 2060 if (!MDS) return nullptr; 2061 2062 return llvm::ConstantInt::get(Int64Ty, llvm::MD5Hash(MDS->getString())); 2063 } 2064 2065 llvm::ConstantInt *CodeGenModule::CreateKCFITypeId(QualType T) { 2066 if (auto *FnType = T->getAs<FunctionProtoType>()) 2067 T = getContext().getFunctionType( 2068 FnType->getReturnType(), FnType->getParamTypes(), 2069 FnType->getExtProtoInfo().withExceptionSpec(EST_None)); 2070 2071 std::string OutName; 2072 llvm::raw_string_ostream Out(OutName); 2073 getCXXABI().getMangleContext().mangleCanonicalTypeName( 2074 T, Out, getCodeGenOpts().SanitizeCfiICallNormalizeIntegers); 2075 2076 if (getCodeGenOpts().SanitizeCfiICallNormalizeIntegers) 2077 Out << ".normalized"; 2078 2079 return llvm::ConstantInt::get(Int32Ty, 2080 static_cast<uint32_t>(llvm::xxHash64(OutName))); 2081 } 2082 2083 void CodeGenModule::SetLLVMFunctionAttributes(GlobalDecl GD, 2084 const CGFunctionInfo &Info, 2085 llvm::Function *F, bool IsThunk) { 2086 unsigned CallingConv; 2087 llvm::AttributeList PAL; 2088 ConstructAttributeList(F->getName(), Info, GD, PAL, CallingConv, 2089 /*AttrOnCallSite=*/false, IsThunk); 2090 F->setAttributes(PAL); 2091 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv)); 2092 } 2093 2094 static void removeImageAccessQualifier(std::string& TyName) { 2095 std::string ReadOnlyQual("__read_only"); 2096 std::string::size_type ReadOnlyPos = TyName.find(ReadOnlyQual); 2097 if (ReadOnlyPos != std::string::npos) 2098 // "+ 1" for the space after access qualifier. 2099 TyName.erase(ReadOnlyPos, ReadOnlyQual.size() + 1); 2100 else { 2101 std::string WriteOnlyQual("__write_only"); 2102 std::string::size_type WriteOnlyPos = TyName.find(WriteOnlyQual); 2103 if (WriteOnlyPos != std::string::npos) 2104 TyName.erase(WriteOnlyPos, WriteOnlyQual.size() + 1); 2105 else { 2106 std::string ReadWriteQual("__read_write"); 2107 std::string::size_type ReadWritePos = TyName.find(ReadWriteQual); 2108 if (ReadWritePos != std::string::npos) 2109 TyName.erase(ReadWritePos, ReadWriteQual.size() + 1); 2110 } 2111 } 2112 } 2113 2114 // Returns the address space id that should be produced to the 2115 // kernel_arg_addr_space metadata. This is always fixed to the ids 2116 // as specified in the SPIR 2.0 specification in order to differentiate 2117 // for example in clGetKernelArgInfo() implementation between the address 2118 // spaces with targets without unique mapping to the OpenCL address spaces 2119 // (basically all single AS CPUs). 2120 static unsigned ArgInfoAddressSpace(LangAS AS) { 2121 switch (AS) { 2122 case LangAS::opencl_global: 2123 return 1; 2124 case LangAS::opencl_constant: 2125 return 2; 2126 case LangAS::opencl_local: 2127 return 3; 2128 case LangAS::opencl_generic: 2129 return 4; // Not in SPIR 2.0 specs. 2130 case LangAS::opencl_global_device: 2131 return 5; 2132 case LangAS::opencl_global_host: 2133 return 6; 2134 default: 2135 return 0; // Assume private. 2136 } 2137 } 2138 2139 void CodeGenModule::GenKernelArgMetadata(llvm::Function *Fn, 2140 const FunctionDecl *FD, 2141 CodeGenFunction *CGF) { 2142 assert(((FD && CGF) || (!FD && !CGF)) && 2143 "Incorrect use - FD and CGF should either be both null or not!"); 2144 // Create MDNodes that represent the kernel arg metadata. 2145 // Each MDNode is a list in the form of "key", N number of values which is 2146 // the same number of values as their are kernel arguments. 2147 2148 const PrintingPolicy &Policy = Context.getPrintingPolicy(); 2149 2150 // MDNode for the kernel argument address space qualifiers. 2151 SmallVector<llvm::Metadata *, 8> addressQuals; 2152 2153 // MDNode for the kernel argument access qualifiers (images only). 2154 SmallVector<llvm::Metadata *, 8> accessQuals; 2155 2156 // MDNode for the kernel argument type names. 2157 SmallVector<llvm::Metadata *, 8> argTypeNames; 2158 2159 // MDNode for the kernel argument base type names. 2160 SmallVector<llvm::Metadata *, 8> argBaseTypeNames; 2161 2162 // MDNode for the kernel argument type qualifiers. 2163 SmallVector<llvm::Metadata *, 8> argTypeQuals; 2164 2165 // MDNode for the kernel argument names. 2166 SmallVector<llvm::Metadata *, 8> argNames; 2167 2168 if (FD && CGF) 2169 for (unsigned i = 0, e = FD->getNumParams(); i != e; ++i) { 2170 const ParmVarDecl *parm = FD->getParamDecl(i); 2171 // Get argument name. 2172 argNames.push_back(llvm::MDString::get(VMContext, parm->getName())); 2173 2174 if (!getLangOpts().OpenCL) 2175 continue; 2176 QualType ty = parm->getType(); 2177 std::string typeQuals; 2178 2179 // Get image and pipe access qualifier: 2180 if (ty->isImageType() || ty->isPipeType()) { 2181 const Decl *PDecl = parm; 2182 if (const auto *TD = ty->getAs<TypedefType>()) 2183 PDecl = TD->getDecl(); 2184 const OpenCLAccessAttr *A = PDecl->getAttr<OpenCLAccessAttr>(); 2185 if (A && A->isWriteOnly()) 2186 accessQuals.push_back(llvm::MDString::get(VMContext, "write_only")); 2187 else if (A && A->isReadWrite()) 2188 accessQuals.push_back(llvm::MDString::get(VMContext, "read_write")); 2189 else 2190 accessQuals.push_back(llvm::MDString::get(VMContext, "read_only")); 2191 } else 2192 accessQuals.push_back(llvm::MDString::get(VMContext, "none")); 2193 2194 auto getTypeSpelling = [&](QualType Ty) { 2195 auto typeName = Ty.getUnqualifiedType().getAsString(Policy); 2196 2197 if (Ty.isCanonical()) { 2198 StringRef typeNameRef = typeName; 2199 // Turn "unsigned type" to "utype" 2200 if (typeNameRef.consume_front("unsigned ")) 2201 return std::string("u") + typeNameRef.str(); 2202 if (typeNameRef.consume_front("signed ")) 2203 return typeNameRef.str(); 2204 } 2205 2206 return typeName; 2207 }; 2208 2209 if (ty->isPointerType()) { 2210 QualType pointeeTy = ty->getPointeeType(); 2211 2212 // Get address qualifier. 2213 addressQuals.push_back( 2214 llvm::ConstantAsMetadata::get(CGF->Builder.getInt32( 2215 ArgInfoAddressSpace(pointeeTy.getAddressSpace())))); 2216 2217 // Get argument type name. 2218 std::string typeName = getTypeSpelling(pointeeTy) + "*"; 2219 std::string baseTypeName = 2220 getTypeSpelling(pointeeTy.getCanonicalType()) + "*"; 2221 argTypeNames.push_back(llvm::MDString::get(VMContext, typeName)); 2222 argBaseTypeNames.push_back( 2223 llvm::MDString::get(VMContext, baseTypeName)); 2224 2225 // Get argument type qualifiers: 2226 if (ty.isRestrictQualified()) 2227 typeQuals = "restrict"; 2228 if (pointeeTy.isConstQualified() || 2229 (pointeeTy.getAddressSpace() == LangAS::opencl_constant)) 2230 typeQuals += typeQuals.empty() ? "const" : " const"; 2231 if (pointeeTy.isVolatileQualified()) 2232 typeQuals += typeQuals.empty() ? "volatile" : " volatile"; 2233 } else { 2234 uint32_t AddrSpc = 0; 2235 bool isPipe = ty->isPipeType(); 2236 if (ty->isImageType() || isPipe) 2237 AddrSpc = ArgInfoAddressSpace(LangAS::opencl_global); 2238 2239 addressQuals.push_back( 2240 llvm::ConstantAsMetadata::get(CGF->Builder.getInt32(AddrSpc))); 2241 2242 // Get argument type name. 2243 ty = isPipe ? ty->castAs<PipeType>()->getElementType() : ty; 2244 std::string typeName = getTypeSpelling(ty); 2245 std::string baseTypeName = getTypeSpelling(ty.getCanonicalType()); 2246 2247 // Remove access qualifiers on images 2248 // (as they are inseparable from type in clang implementation, 2249 // but OpenCL spec provides a special query to get access qualifier 2250 // via clGetKernelArgInfo with CL_KERNEL_ARG_ACCESS_QUALIFIER): 2251 if (ty->isImageType()) { 2252 removeImageAccessQualifier(typeName); 2253 removeImageAccessQualifier(baseTypeName); 2254 } 2255 2256 argTypeNames.push_back(llvm::MDString::get(VMContext, typeName)); 2257 argBaseTypeNames.push_back( 2258 llvm::MDString::get(VMContext, baseTypeName)); 2259 2260 if (isPipe) 2261 typeQuals = "pipe"; 2262 } 2263 argTypeQuals.push_back(llvm::MDString::get(VMContext, typeQuals)); 2264 } 2265 2266 if (getLangOpts().OpenCL) { 2267 Fn->setMetadata("kernel_arg_addr_space", 2268 llvm::MDNode::get(VMContext, addressQuals)); 2269 Fn->setMetadata("kernel_arg_access_qual", 2270 llvm::MDNode::get(VMContext, accessQuals)); 2271 Fn->setMetadata("kernel_arg_type", 2272 llvm::MDNode::get(VMContext, argTypeNames)); 2273 Fn->setMetadata("kernel_arg_base_type", 2274 llvm::MDNode::get(VMContext, argBaseTypeNames)); 2275 Fn->setMetadata("kernel_arg_type_qual", 2276 llvm::MDNode::get(VMContext, argTypeQuals)); 2277 } 2278 if (getCodeGenOpts().EmitOpenCLArgMetadata || 2279 getCodeGenOpts().HIPSaveKernelArgName) 2280 Fn->setMetadata("kernel_arg_name", 2281 llvm::MDNode::get(VMContext, argNames)); 2282 } 2283 2284 /// Determines whether the language options require us to model 2285 /// unwind exceptions. We treat -fexceptions as mandating this 2286 /// except under the fragile ObjC ABI with only ObjC exceptions 2287 /// enabled. This means, for example, that C with -fexceptions 2288 /// enables this. 2289 static bool hasUnwindExceptions(const LangOptions &LangOpts) { 2290 // If exceptions are completely disabled, obviously this is false. 2291 if (!LangOpts.Exceptions) return false; 2292 2293 // If C++ exceptions are enabled, this is true. 2294 if (LangOpts.CXXExceptions) return true; 2295 2296 // If ObjC exceptions are enabled, this depends on the ABI. 2297 if (LangOpts.ObjCExceptions) { 2298 return LangOpts.ObjCRuntime.hasUnwindExceptions(); 2299 } 2300 2301 return true; 2302 } 2303 2304 static bool requiresMemberFunctionPointerTypeMetadata(CodeGenModule &CGM, 2305 const CXXMethodDecl *MD) { 2306 // Check that the type metadata can ever actually be used by a call. 2307 if (!CGM.getCodeGenOpts().LTOUnit || 2308 !CGM.HasHiddenLTOVisibility(MD->getParent())) 2309 return false; 2310 2311 // Only functions whose address can be taken with a member function pointer 2312 // need this sort of type metadata. 2313 return MD->isImplicitObjectMemberFunction() && !MD->isVirtual() && 2314 !isa<CXXConstructorDecl, CXXDestructorDecl>(MD); 2315 } 2316 2317 SmallVector<const CXXRecordDecl *, 0> 2318 CodeGenModule::getMostBaseClasses(const CXXRecordDecl *RD) { 2319 llvm::SetVector<const CXXRecordDecl *> MostBases; 2320 2321 std::function<void (const CXXRecordDecl *)> CollectMostBases; 2322 CollectMostBases = [&](const CXXRecordDecl *RD) { 2323 if (RD->getNumBases() == 0) 2324 MostBases.insert(RD); 2325 for (const CXXBaseSpecifier &B : RD->bases()) 2326 CollectMostBases(B.getType()->getAsCXXRecordDecl()); 2327 }; 2328 CollectMostBases(RD); 2329 return MostBases.takeVector(); 2330 } 2331 2332 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D, 2333 llvm::Function *F) { 2334 llvm::AttrBuilder B(F->getContext()); 2335 2336 if ((!D || !D->hasAttr<NoUwtableAttr>()) && CodeGenOpts.UnwindTables) 2337 B.addUWTableAttr(llvm::UWTableKind(CodeGenOpts.UnwindTables)); 2338 2339 if (CodeGenOpts.StackClashProtector) 2340 B.addAttribute("probe-stack", "inline-asm"); 2341 2342 if (CodeGenOpts.StackProbeSize && CodeGenOpts.StackProbeSize != 4096) 2343 B.addAttribute("stack-probe-size", 2344 std::to_string(CodeGenOpts.StackProbeSize)); 2345 2346 if (!hasUnwindExceptions(LangOpts)) 2347 B.addAttribute(llvm::Attribute::NoUnwind); 2348 2349 if (D && D->hasAttr<NoStackProtectorAttr>()) 2350 ; // Do nothing. 2351 else if (D && D->hasAttr<StrictGuardStackCheckAttr>() && 2352 isStackProtectorOn(LangOpts, getTriple(), LangOptions::SSPOn)) 2353 B.addAttribute(llvm::Attribute::StackProtectStrong); 2354 else if (isStackProtectorOn(LangOpts, getTriple(), LangOptions::SSPOn)) 2355 B.addAttribute(llvm::Attribute::StackProtect); 2356 else if (isStackProtectorOn(LangOpts, getTriple(), LangOptions::SSPStrong)) 2357 B.addAttribute(llvm::Attribute::StackProtectStrong); 2358 else if (isStackProtectorOn(LangOpts, getTriple(), LangOptions::SSPReq)) 2359 B.addAttribute(llvm::Attribute::StackProtectReq); 2360 2361 if (!D) { 2362 // If we don't have a declaration to control inlining, the function isn't 2363 // explicitly marked as alwaysinline for semantic reasons, and inlining is 2364 // disabled, mark the function as noinline. 2365 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline) && 2366 CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining) 2367 B.addAttribute(llvm::Attribute::NoInline); 2368 2369 F->addFnAttrs(B); 2370 return; 2371 } 2372 2373 // Handle SME attributes that apply to function definitions, 2374 // rather than to function prototypes. 2375 if (D->hasAttr<ArmLocallyStreamingAttr>()) 2376 B.addAttribute("aarch64_pstate_sm_body"); 2377 2378 if (auto *Attr = D->getAttr<ArmNewAttr>()) { 2379 if (Attr->isNewZA()) 2380 B.addAttribute("aarch64_new_za"); 2381 if (Attr->isNewZT0()) 2382 B.addAttribute("aarch64_new_zt0"); 2383 } 2384 2385 // Track whether we need to add the optnone LLVM attribute, 2386 // starting with the default for this optimization level. 2387 bool ShouldAddOptNone = 2388 !CodeGenOpts.DisableO0ImplyOptNone && CodeGenOpts.OptimizationLevel == 0; 2389 // We can't add optnone in the following cases, it won't pass the verifier. 2390 ShouldAddOptNone &= !D->hasAttr<MinSizeAttr>(); 2391 ShouldAddOptNone &= !D->hasAttr<AlwaysInlineAttr>(); 2392 2393 // Add optnone, but do so only if the function isn't always_inline. 2394 if ((ShouldAddOptNone || D->hasAttr<OptimizeNoneAttr>()) && 2395 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) { 2396 B.addAttribute(llvm::Attribute::OptimizeNone); 2397 2398 // OptimizeNone implies noinline; we should not be inlining such functions. 2399 B.addAttribute(llvm::Attribute::NoInline); 2400 2401 // We still need to handle naked functions even though optnone subsumes 2402 // much of their semantics. 2403 if (D->hasAttr<NakedAttr>()) 2404 B.addAttribute(llvm::Attribute::Naked); 2405 2406 // OptimizeNone wins over OptimizeForSize and MinSize. 2407 F->removeFnAttr(llvm::Attribute::OptimizeForSize); 2408 F->removeFnAttr(llvm::Attribute::MinSize); 2409 } else if (D->hasAttr<NakedAttr>()) { 2410 // Naked implies noinline: we should not be inlining such functions. 2411 B.addAttribute(llvm::Attribute::Naked); 2412 B.addAttribute(llvm::Attribute::NoInline); 2413 } else if (D->hasAttr<NoDuplicateAttr>()) { 2414 B.addAttribute(llvm::Attribute::NoDuplicate); 2415 } else if (D->hasAttr<NoInlineAttr>() && !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) { 2416 // Add noinline if the function isn't always_inline. 2417 B.addAttribute(llvm::Attribute::NoInline); 2418 } else if (D->hasAttr<AlwaysInlineAttr>() && 2419 !F->hasFnAttribute(llvm::Attribute::NoInline)) { 2420 // (noinline wins over always_inline, and we can't specify both in IR) 2421 B.addAttribute(llvm::Attribute::AlwaysInline); 2422 } else if (CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining) { 2423 // If we're not inlining, then force everything that isn't always_inline to 2424 // carry an explicit noinline attribute. 2425 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline)) 2426 B.addAttribute(llvm::Attribute::NoInline); 2427 } else { 2428 // Otherwise, propagate the inline hint attribute and potentially use its 2429 // absence to mark things as noinline. 2430 if (auto *FD = dyn_cast<FunctionDecl>(D)) { 2431 // Search function and template pattern redeclarations for inline. 2432 auto CheckForInline = [](const FunctionDecl *FD) { 2433 auto CheckRedeclForInline = [](const FunctionDecl *Redecl) { 2434 return Redecl->isInlineSpecified(); 2435 }; 2436 if (any_of(FD->redecls(), CheckRedeclForInline)) 2437 return true; 2438 const FunctionDecl *Pattern = FD->getTemplateInstantiationPattern(); 2439 if (!Pattern) 2440 return false; 2441 return any_of(Pattern->redecls(), CheckRedeclForInline); 2442 }; 2443 if (CheckForInline(FD)) { 2444 B.addAttribute(llvm::Attribute::InlineHint); 2445 } else if (CodeGenOpts.getInlining() == 2446 CodeGenOptions::OnlyHintInlining && 2447 !FD->isInlined() && 2448 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) { 2449 B.addAttribute(llvm::Attribute::NoInline); 2450 } 2451 } 2452 } 2453 2454 // Add other optimization related attributes if we are optimizing this 2455 // function. 2456 if (!D->hasAttr<OptimizeNoneAttr>()) { 2457 if (D->hasAttr<ColdAttr>()) { 2458 if (!ShouldAddOptNone) 2459 B.addAttribute(llvm::Attribute::OptimizeForSize); 2460 B.addAttribute(llvm::Attribute::Cold); 2461 } 2462 if (D->hasAttr<HotAttr>()) 2463 B.addAttribute(llvm::Attribute::Hot); 2464 if (D->hasAttr<MinSizeAttr>()) 2465 B.addAttribute(llvm::Attribute::MinSize); 2466 } 2467 2468 F->addFnAttrs(B); 2469 2470 unsigned alignment = D->getMaxAlignment() / Context.getCharWidth(); 2471 if (alignment) 2472 F->setAlignment(llvm::Align(alignment)); 2473 2474 if (!D->hasAttr<AlignedAttr>()) 2475 if (LangOpts.FunctionAlignment) 2476 F->setAlignment(llvm::Align(1ull << LangOpts.FunctionAlignment)); 2477 2478 // Some C++ ABIs require 2-byte alignment for member functions, in order to 2479 // reserve a bit for differentiating between virtual and non-virtual member 2480 // functions. If the current target's C++ ABI requires this and this is a 2481 // member function, set its alignment accordingly. 2482 if (getTarget().getCXXABI().areMemberFunctionsAligned()) { 2483 if (isa<CXXMethodDecl>(D) && F->getPointerAlignment(getDataLayout()) < 2) 2484 F->setAlignment(std::max(llvm::Align(2), F->getAlign().valueOrOne())); 2485 } 2486 2487 // In the cross-dso CFI mode with canonical jump tables, we want !type 2488 // attributes on definitions only. 2489 if (CodeGenOpts.SanitizeCfiCrossDso && 2490 CodeGenOpts.SanitizeCfiCanonicalJumpTables) { 2491 if (auto *FD = dyn_cast<FunctionDecl>(D)) { 2492 // Skip available_externally functions. They won't be codegen'ed in the 2493 // current module anyway. 2494 if (getContext().GetGVALinkageForFunction(FD) != GVA_AvailableExternally) 2495 CreateFunctionTypeMetadataForIcall(FD, F); 2496 } 2497 } 2498 2499 // Emit type metadata on member functions for member function pointer checks. 2500 // These are only ever necessary on definitions; we're guaranteed that the 2501 // definition will be present in the LTO unit as a result of LTO visibility. 2502 auto *MD = dyn_cast<CXXMethodDecl>(D); 2503 if (MD && requiresMemberFunctionPointerTypeMetadata(*this, MD)) { 2504 for (const CXXRecordDecl *Base : getMostBaseClasses(MD->getParent())) { 2505 llvm::Metadata *Id = 2506 CreateMetadataIdentifierForType(Context.getMemberPointerType( 2507 MD->getType(), Context.getRecordType(Base).getTypePtr())); 2508 F->addTypeMetadata(0, Id); 2509 } 2510 } 2511 } 2512 2513 void CodeGenModule::SetCommonAttributes(GlobalDecl GD, llvm::GlobalValue *GV) { 2514 const Decl *D = GD.getDecl(); 2515 if (isa_and_nonnull<NamedDecl>(D)) 2516 setGVProperties(GV, GD); 2517 else 2518 GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 2519 2520 if (D && D->hasAttr<UsedAttr>()) 2521 addUsedOrCompilerUsedGlobal(GV); 2522 2523 if (const auto *VD = dyn_cast_if_present<VarDecl>(D); 2524 VD && 2525 ((CodeGenOpts.KeepPersistentStorageVariables && 2526 (VD->getStorageDuration() == SD_Static || 2527 VD->getStorageDuration() == SD_Thread)) || 2528 (CodeGenOpts.KeepStaticConsts && VD->getStorageDuration() == SD_Static && 2529 VD->getType().isConstQualified()))) 2530 addUsedOrCompilerUsedGlobal(GV); 2531 } 2532 2533 bool CodeGenModule::GetCPUAndFeaturesAttributes(GlobalDecl GD, 2534 llvm::AttrBuilder &Attrs, 2535 bool SetTargetFeatures) { 2536 // Add target-cpu and target-features attributes to functions. If 2537 // we have a decl for the function and it has a target attribute then 2538 // parse that and add it to the feature set. 2539 StringRef TargetCPU = getTarget().getTargetOpts().CPU; 2540 StringRef TuneCPU = getTarget().getTargetOpts().TuneCPU; 2541 std::vector<std::string> Features; 2542 const auto *FD = dyn_cast_or_null<FunctionDecl>(GD.getDecl()); 2543 FD = FD ? FD->getMostRecentDecl() : FD; 2544 const auto *TD = FD ? FD->getAttr<TargetAttr>() : nullptr; 2545 const auto *TV = FD ? FD->getAttr<TargetVersionAttr>() : nullptr; 2546 assert((!TD || !TV) && "both target_version and target specified"); 2547 const auto *SD = FD ? FD->getAttr<CPUSpecificAttr>() : nullptr; 2548 const auto *TC = FD ? FD->getAttr<TargetClonesAttr>() : nullptr; 2549 bool AddedAttr = false; 2550 if (TD || TV || SD || TC) { 2551 llvm::StringMap<bool> FeatureMap; 2552 getContext().getFunctionFeatureMap(FeatureMap, GD); 2553 2554 // Produce the canonical string for this set of features. 2555 for (const llvm::StringMap<bool>::value_type &Entry : FeatureMap) 2556 Features.push_back((Entry.getValue() ? "+" : "-") + Entry.getKey().str()); 2557 2558 // Now add the target-cpu and target-features to the function. 2559 // While we populated the feature map above, we still need to 2560 // get and parse the target attribute so we can get the cpu for 2561 // the function. 2562 if (TD) { 2563 ParsedTargetAttr ParsedAttr = 2564 Target.parseTargetAttr(TD->getFeaturesStr()); 2565 if (!ParsedAttr.CPU.empty() && 2566 getTarget().isValidCPUName(ParsedAttr.CPU)) { 2567 TargetCPU = ParsedAttr.CPU; 2568 TuneCPU = ""; // Clear the tune CPU. 2569 } 2570 if (!ParsedAttr.Tune.empty() && 2571 getTarget().isValidCPUName(ParsedAttr.Tune)) 2572 TuneCPU = ParsedAttr.Tune; 2573 } 2574 2575 if (SD) { 2576 // Apply the given CPU name as the 'tune-cpu' so that the optimizer can 2577 // favor this processor. 2578 TuneCPU = SD->getCPUName(GD.getMultiVersionIndex())->getName(); 2579 } 2580 } else { 2581 // Otherwise just add the existing target cpu and target features to the 2582 // function. 2583 Features = getTarget().getTargetOpts().Features; 2584 } 2585 2586 if (!TargetCPU.empty()) { 2587 Attrs.addAttribute("target-cpu", TargetCPU); 2588 AddedAttr = true; 2589 } 2590 if (!TuneCPU.empty()) { 2591 Attrs.addAttribute("tune-cpu", TuneCPU); 2592 AddedAttr = true; 2593 } 2594 if (!Features.empty() && SetTargetFeatures) { 2595 llvm::erase_if(Features, [&](const std::string& F) { 2596 return getTarget().isReadOnlyFeature(F.substr(1)); 2597 }); 2598 llvm::sort(Features); 2599 Attrs.addAttribute("target-features", llvm::join(Features, ",")); 2600 AddedAttr = true; 2601 } 2602 2603 return AddedAttr; 2604 } 2605 2606 void CodeGenModule::setNonAliasAttributes(GlobalDecl GD, 2607 llvm::GlobalObject *GO) { 2608 const Decl *D = GD.getDecl(); 2609 SetCommonAttributes(GD, GO); 2610 2611 if (D) { 2612 if (auto *GV = dyn_cast<llvm::GlobalVariable>(GO)) { 2613 if (D->hasAttr<RetainAttr>()) 2614 addUsedGlobal(GV); 2615 if (auto *SA = D->getAttr<PragmaClangBSSSectionAttr>()) 2616 GV->addAttribute("bss-section", SA->getName()); 2617 if (auto *SA = D->getAttr<PragmaClangDataSectionAttr>()) 2618 GV->addAttribute("data-section", SA->getName()); 2619 if (auto *SA = D->getAttr<PragmaClangRodataSectionAttr>()) 2620 GV->addAttribute("rodata-section", SA->getName()); 2621 if (auto *SA = D->getAttr<PragmaClangRelroSectionAttr>()) 2622 GV->addAttribute("relro-section", SA->getName()); 2623 } 2624 2625 if (auto *F = dyn_cast<llvm::Function>(GO)) { 2626 if (D->hasAttr<RetainAttr>()) 2627 addUsedGlobal(F); 2628 if (auto *SA = D->getAttr<PragmaClangTextSectionAttr>()) 2629 if (!D->getAttr<SectionAttr>()) 2630 F->addFnAttr("implicit-section-name", SA->getName()); 2631 2632 llvm::AttrBuilder Attrs(F->getContext()); 2633 if (GetCPUAndFeaturesAttributes(GD, Attrs)) { 2634 // We know that GetCPUAndFeaturesAttributes will always have the 2635 // newest set, since it has the newest possible FunctionDecl, so the 2636 // new ones should replace the old. 2637 llvm::AttributeMask RemoveAttrs; 2638 RemoveAttrs.addAttribute("target-cpu"); 2639 RemoveAttrs.addAttribute("target-features"); 2640 RemoveAttrs.addAttribute("tune-cpu"); 2641 F->removeFnAttrs(RemoveAttrs); 2642 F->addFnAttrs(Attrs); 2643 } 2644 } 2645 2646 if (const auto *CSA = D->getAttr<CodeSegAttr>()) 2647 GO->setSection(CSA->getName()); 2648 else if (const auto *SA = D->getAttr<SectionAttr>()) 2649 GO->setSection(SA->getName()); 2650 } 2651 2652 getTargetCodeGenInfo().setTargetAttributes(D, GO, *this); 2653 } 2654 2655 void CodeGenModule::SetInternalFunctionAttributes(GlobalDecl GD, 2656 llvm::Function *F, 2657 const CGFunctionInfo &FI) { 2658 const Decl *D = GD.getDecl(); 2659 SetLLVMFunctionAttributes(GD, FI, F, /*IsThunk=*/false); 2660 SetLLVMFunctionAttributesForDefinition(D, F); 2661 2662 F->setLinkage(llvm::Function::InternalLinkage); 2663 2664 setNonAliasAttributes(GD, F); 2665 } 2666 2667 static void setLinkageForGV(llvm::GlobalValue *GV, const NamedDecl *ND) { 2668 // Set linkage and visibility in case we never see a definition. 2669 LinkageInfo LV = ND->getLinkageAndVisibility(); 2670 // Don't set internal linkage on declarations. 2671 // "extern_weak" is overloaded in LLVM; we probably should have 2672 // separate linkage types for this. 2673 if (isExternallyVisible(LV.getLinkage()) && 2674 (ND->hasAttr<WeakAttr>() || ND->isWeakImported())) 2675 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage); 2676 } 2677 2678 void CodeGenModule::CreateFunctionTypeMetadataForIcall(const FunctionDecl *FD, 2679 llvm::Function *F) { 2680 // Only if we are checking indirect calls. 2681 if (!LangOpts.Sanitize.has(SanitizerKind::CFIICall)) 2682 return; 2683 2684 // Non-static class methods are handled via vtable or member function pointer 2685 // checks elsewhere. 2686 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 2687 return; 2688 2689 llvm::Metadata *MD = CreateMetadataIdentifierForType(FD->getType()); 2690 F->addTypeMetadata(0, MD); 2691 F->addTypeMetadata(0, CreateMetadataIdentifierGeneralized(FD->getType())); 2692 2693 // Emit a hash-based bit set entry for cross-DSO calls. 2694 if (CodeGenOpts.SanitizeCfiCrossDso) 2695 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD)) 2696 F->addTypeMetadata(0, llvm::ConstantAsMetadata::get(CrossDsoTypeId)); 2697 } 2698 2699 void CodeGenModule::setKCFIType(const FunctionDecl *FD, llvm::Function *F) { 2700 llvm::LLVMContext &Ctx = F->getContext(); 2701 llvm::MDBuilder MDB(Ctx); 2702 F->setMetadata(llvm::LLVMContext::MD_kcfi_type, 2703 llvm::MDNode::get( 2704 Ctx, MDB.createConstant(CreateKCFITypeId(FD->getType())))); 2705 } 2706 2707 static bool allowKCFIIdentifier(StringRef Name) { 2708 // KCFI type identifier constants are only necessary for external assembly 2709 // functions, which means it's safe to skip unusual names. Subset of 2710 // MCAsmInfo::isAcceptableChar() and MCAsmInfoXCOFF::isAcceptableChar(). 2711 return llvm::all_of(Name, [](const char &C) { 2712 return llvm::isAlnum(C) || C == '_' || C == '.'; 2713 }); 2714 } 2715 2716 void CodeGenModule::finalizeKCFITypes() { 2717 llvm::Module &M = getModule(); 2718 for (auto &F : M.functions()) { 2719 // Remove KCFI type metadata from non-address-taken local functions. 2720 bool AddressTaken = F.hasAddressTaken(); 2721 if (!AddressTaken && F.hasLocalLinkage()) 2722 F.eraseMetadata(llvm::LLVMContext::MD_kcfi_type); 2723 2724 // Generate a constant with the expected KCFI type identifier for all 2725 // address-taken function declarations to support annotating indirectly 2726 // called assembly functions. 2727 if (!AddressTaken || !F.isDeclaration()) 2728 continue; 2729 2730 const llvm::ConstantInt *Type; 2731 if (const llvm::MDNode *MD = F.getMetadata(llvm::LLVMContext::MD_kcfi_type)) 2732 Type = llvm::mdconst::extract<llvm::ConstantInt>(MD->getOperand(0)); 2733 else 2734 continue; 2735 2736 StringRef Name = F.getName(); 2737 if (!allowKCFIIdentifier(Name)) 2738 continue; 2739 2740 std::string Asm = (".weak __kcfi_typeid_" + Name + "\n.set __kcfi_typeid_" + 2741 Name + ", " + Twine(Type->getZExtValue()) + "\n") 2742 .str(); 2743 M.appendModuleInlineAsm(Asm); 2744 } 2745 } 2746 2747 void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, llvm::Function *F, 2748 bool IsIncompleteFunction, 2749 bool IsThunk) { 2750 2751 if (llvm::Intrinsic::ID IID = F->getIntrinsicID()) { 2752 // If this is an intrinsic function, set the function's attributes 2753 // to the intrinsic's attributes. 2754 F->setAttributes(llvm::Intrinsic::getAttributes(getLLVMContext(), IID)); 2755 return; 2756 } 2757 2758 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 2759 2760 if (!IsIncompleteFunction) 2761 SetLLVMFunctionAttributes(GD, getTypes().arrangeGlobalDeclaration(GD), F, 2762 IsThunk); 2763 2764 // Add the Returned attribute for "this", except for iOS 5 and earlier 2765 // where substantial code, including the libstdc++ dylib, was compiled with 2766 // GCC and does not actually return "this". 2767 if (!IsThunk && getCXXABI().HasThisReturn(GD) && 2768 !(getTriple().isiOS() && getTriple().isOSVersionLT(6))) { 2769 assert(!F->arg_empty() && 2770 F->arg_begin()->getType() 2771 ->canLosslesslyBitCastTo(F->getReturnType()) && 2772 "unexpected this return"); 2773 F->addParamAttr(0, llvm::Attribute::Returned); 2774 } 2775 2776 // Only a few attributes are set on declarations; these may later be 2777 // overridden by a definition. 2778 2779 setLinkageForGV(F, FD); 2780 setGVProperties(F, FD); 2781 2782 // Setup target-specific attributes. 2783 if (!IsIncompleteFunction && F->isDeclaration()) 2784 getTargetCodeGenInfo().setTargetAttributes(FD, F, *this); 2785 2786 if (const auto *CSA = FD->getAttr<CodeSegAttr>()) 2787 F->setSection(CSA->getName()); 2788 else if (const auto *SA = FD->getAttr<SectionAttr>()) 2789 F->setSection(SA->getName()); 2790 2791 if (const auto *EA = FD->getAttr<ErrorAttr>()) { 2792 if (EA->isError()) 2793 F->addFnAttr("dontcall-error", EA->getUserDiagnostic()); 2794 else if (EA->isWarning()) 2795 F->addFnAttr("dontcall-warn", EA->getUserDiagnostic()); 2796 } 2797 2798 // If we plan on emitting this inline builtin, we can't treat it as a builtin. 2799 if (FD->isInlineBuiltinDeclaration()) { 2800 const FunctionDecl *FDBody; 2801 bool HasBody = FD->hasBody(FDBody); 2802 (void)HasBody; 2803 assert(HasBody && "Inline builtin declarations should always have an " 2804 "available body!"); 2805 if (shouldEmitFunction(FDBody)) 2806 F->addFnAttr(llvm::Attribute::NoBuiltin); 2807 } 2808 2809 if (FD->isReplaceableGlobalAllocationFunction()) { 2810 // A replaceable global allocation function does not act like a builtin by 2811 // default, only if it is invoked by a new-expression or delete-expression. 2812 F->addFnAttr(llvm::Attribute::NoBuiltin); 2813 } 2814 2815 if (isa<CXXConstructorDecl>(FD) || isa<CXXDestructorDecl>(FD)) 2816 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 2817 else if (const auto *MD = dyn_cast<CXXMethodDecl>(FD)) 2818 if (MD->isVirtual()) 2819 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 2820 2821 // Don't emit entries for function declarations in the cross-DSO mode. This 2822 // is handled with better precision by the receiving DSO. But if jump tables 2823 // are non-canonical then we need type metadata in order to produce the local 2824 // jump table. 2825 if (!CodeGenOpts.SanitizeCfiCrossDso || 2826 !CodeGenOpts.SanitizeCfiCanonicalJumpTables) 2827 CreateFunctionTypeMetadataForIcall(FD, F); 2828 2829 if (LangOpts.Sanitize.has(SanitizerKind::KCFI)) 2830 setKCFIType(FD, F); 2831 2832 if (getLangOpts().OpenMP && FD->hasAttr<OMPDeclareSimdDeclAttr>()) 2833 getOpenMPRuntime().emitDeclareSimdFunction(FD, F); 2834 2835 if (CodeGenOpts.InlineMaxStackSize != UINT_MAX) 2836 F->addFnAttr("inline-max-stacksize", llvm::utostr(CodeGenOpts.InlineMaxStackSize)); 2837 2838 if (const auto *CB = FD->getAttr<CallbackAttr>()) { 2839 // Annotate the callback behavior as metadata: 2840 // - The callback callee (as argument number). 2841 // - The callback payloads (as argument numbers). 2842 llvm::LLVMContext &Ctx = F->getContext(); 2843 llvm::MDBuilder MDB(Ctx); 2844 2845 // The payload indices are all but the first one in the encoding. The first 2846 // identifies the callback callee. 2847 int CalleeIdx = *CB->encoding_begin(); 2848 ArrayRef<int> PayloadIndices(CB->encoding_begin() + 1, CB->encoding_end()); 2849 F->addMetadata(llvm::LLVMContext::MD_callback, 2850 *llvm::MDNode::get(Ctx, {MDB.createCallbackEncoding( 2851 CalleeIdx, PayloadIndices, 2852 /* VarArgsArePassed */ false)})); 2853 } 2854 } 2855 2856 void CodeGenModule::addUsedGlobal(llvm::GlobalValue *GV) { 2857 assert((isa<llvm::Function>(GV) || !GV->isDeclaration()) && 2858 "Only globals with definition can force usage."); 2859 LLVMUsed.emplace_back(GV); 2860 } 2861 2862 void CodeGenModule::addCompilerUsedGlobal(llvm::GlobalValue *GV) { 2863 assert(!GV->isDeclaration() && 2864 "Only globals with definition can force usage."); 2865 LLVMCompilerUsed.emplace_back(GV); 2866 } 2867 2868 void CodeGenModule::addUsedOrCompilerUsedGlobal(llvm::GlobalValue *GV) { 2869 assert((isa<llvm::Function>(GV) || !GV->isDeclaration()) && 2870 "Only globals with definition can force usage."); 2871 if (getTriple().isOSBinFormatELF()) 2872 LLVMCompilerUsed.emplace_back(GV); 2873 else 2874 LLVMUsed.emplace_back(GV); 2875 } 2876 2877 static void emitUsed(CodeGenModule &CGM, StringRef Name, 2878 std::vector<llvm::WeakTrackingVH> &List) { 2879 // Don't create llvm.used if there is no need. 2880 if (List.empty()) 2881 return; 2882 2883 // Convert List to what ConstantArray needs. 2884 SmallVector<llvm::Constant*, 8> UsedArray; 2885 UsedArray.resize(List.size()); 2886 for (unsigned i = 0, e = List.size(); i != e; ++i) { 2887 UsedArray[i] = 2888 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast( 2889 cast<llvm::Constant>(&*List[i]), CGM.Int8PtrTy); 2890 } 2891 2892 if (UsedArray.empty()) 2893 return; 2894 llvm::ArrayType *ATy = llvm::ArrayType::get(CGM.Int8PtrTy, UsedArray.size()); 2895 2896 auto *GV = new llvm::GlobalVariable( 2897 CGM.getModule(), ATy, false, llvm::GlobalValue::AppendingLinkage, 2898 llvm::ConstantArray::get(ATy, UsedArray), Name); 2899 2900 GV->setSection("llvm.metadata"); 2901 } 2902 2903 void CodeGenModule::emitLLVMUsed() { 2904 emitUsed(*this, "llvm.used", LLVMUsed); 2905 emitUsed(*this, "llvm.compiler.used", LLVMCompilerUsed); 2906 } 2907 2908 void CodeGenModule::AppendLinkerOptions(StringRef Opts) { 2909 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opts); 2910 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts)); 2911 } 2912 2913 void CodeGenModule::AddDetectMismatch(StringRef Name, StringRef Value) { 2914 llvm::SmallString<32> Opt; 2915 getTargetCodeGenInfo().getDetectMismatchOption(Name, Value, Opt); 2916 if (Opt.empty()) 2917 return; 2918 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt); 2919 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts)); 2920 } 2921 2922 void CodeGenModule::AddDependentLib(StringRef Lib) { 2923 auto &C = getLLVMContext(); 2924 if (getTarget().getTriple().isOSBinFormatELF()) { 2925 ELFDependentLibraries.push_back( 2926 llvm::MDNode::get(C, llvm::MDString::get(C, Lib))); 2927 return; 2928 } 2929 2930 llvm::SmallString<24> Opt; 2931 getTargetCodeGenInfo().getDependentLibraryOption(Lib, Opt); 2932 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt); 2933 LinkerOptionsMetadata.push_back(llvm::MDNode::get(C, MDOpts)); 2934 } 2935 2936 /// Add link options implied by the given module, including modules 2937 /// it depends on, using a postorder walk. 2938 static void addLinkOptionsPostorder(CodeGenModule &CGM, Module *Mod, 2939 SmallVectorImpl<llvm::MDNode *> &Metadata, 2940 llvm::SmallPtrSet<Module *, 16> &Visited) { 2941 // Import this module's parent. 2942 if (Mod->Parent && Visited.insert(Mod->Parent).second) { 2943 addLinkOptionsPostorder(CGM, Mod->Parent, Metadata, Visited); 2944 } 2945 2946 // Import this module's dependencies. 2947 for (Module *Import : llvm::reverse(Mod->Imports)) { 2948 if (Visited.insert(Import).second) 2949 addLinkOptionsPostorder(CGM, Import, Metadata, Visited); 2950 } 2951 2952 // Add linker options to link against the libraries/frameworks 2953 // described by this module. 2954 llvm::LLVMContext &Context = CGM.getLLVMContext(); 2955 bool IsELF = CGM.getTarget().getTriple().isOSBinFormatELF(); 2956 2957 // For modules that use export_as for linking, use that module 2958 // name instead. 2959 if (Mod->UseExportAsModuleLinkName) 2960 return; 2961 2962 for (const Module::LinkLibrary &LL : llvm::reverse(Mod->LinkLibraries)) { 2963 // Link against a framework. Frameworks are currently Darwin only, so we 2964 // don't to ask TargetCodeGenInfo for the spelling of the linker option. 2965 if (LL.IsFramework) { 2966 llvm::Metadata *Args[2] = {llvm::MDString::get(Context, "-framework"), 2967 llvm::MDString::get(Context, LL.Library)}; 2968 2969 Metadata.push_back(llvm::MDNode::get(Context, Args)); 2970 continue; 2971 } 2972 2973 // Link against a library. 2974 if (IsELF) { 2975 llvm::Metadata *Args[2] = { 2976 llvm::MDString::get(Context, "lib"), 2977 llvm::MDString::get(Context, LL.Library), 2978 }; 2979 Metadata.push_back(llvm::MDNode::get(Context, Args)); 2980 } else { 2981 llvm::SmallString<24> Opt; 2982 CGM.getTargetCodeGenInfo().getDependentLibraryOption(LL.Library, Opt); 2983 auto *OptString = llvm::MDString::get(Context, Opt); 2984 Metadata.push_back(llvm::MDNode::get(Context, OptString)); 2985 } 2986 } 2987 } 2988 2989 void CodeGenModule::EmitModuleInitializers(clang::Module *Primary) { 2990 assert(Primary->isNamedModuleUnit() && 2991 "We should only emit module initializers for named modules."); 2992 2993 // Emit the initializers in the order that sub-modules appear in the 2994 // source, first Global Module Fragments, if present. 2995 if (auto GMF = Primary->getGlobalModuleFragment()) { 2996 for (Decl *D : getContext().getModuleInitializers(GMF)) { 2997 if (isa<ImportDecl>(D)) 2998 continue; 2999 assert(isa<VarDecl>(D) && "GMF initializer decl is not a var?"); 3000 EmitTopLevelDecl(D); 3001 } 3002 } 3003 // Second any associated with the module, itself. 3004 for (Decl *D : getContext().getModuleInitializers(Primary)) { 3005 // Skip import decls, the inits for those are called explicitly. 3006 if (isa<ImportDecl>(D)) 3007 continue; 3008 EmitTopLevelDecl(D); 3009 } 3010 // Third any associated with the Privat eMOdule Fragment, if present. 3011 if (auto PMF = Primary->getPrivateModuleFragment()) { 3012 for (Decl *D : getContext().getModuleInitializers(PMF)) { 3013 // Skip import decls, the inits for those are called explicitly. 3014 if (isa<ImportDecl>(D)) 3015 continue; 3016 assert(isa<VarDecl>(D) && "PMF initializer decl is not a var?"); 3017 EmitTopLevelDecl(D); 3018 } 3019 } 3020 } 3021 3022 void CodeGenModule::EmitModuleLinkOptions() { 3023 // Collect the set of all of the modules we want to visit to emit link 3024 // options, which is essentially the imported modules and all of their 3025 // non-explicit child modules. 3026 llvm::SetVector<clang::Module *> LinkModules; 3027 llvm::SmallPtrSet<clang::Module *, 16> Visited; 3028 SmallVector<clang::Module *, 16> Stack; 3029 3030 // Seed the stack with imported modules. 3031 for (Module *M : ImportedModules) { 3032 // Do not add any link flags when an implementation TU of a module imports 3033 // a header of that same module. 3034 if (M->getTopLevelModuleName() == getLangOpts().CurrentModule && 3035 !getLangOpts().isCompilingModule()) 3036 continue; 3037 if (Visited.insert(M).second) 3038 Stack.push_back(M); 3039 } 3040 3041 // Find all of the modules to import, making a little effort to prune 3042 // non-leaf modules. 3043 while (!Stack.empty()) { 3044 clang::Module *Mod = Stack.pop_back_val(); 3045 3046 bool AnyChildren = false; 3047 3048 // Visit the submodules of this module. 3049 for (const auto &SM : Mod->submodules()) { 3050 // Skip explicit children; they need to be explicitly imported to be 3051 // linked against. 3052 if (SM->IsExplicit) 3053 continue; 3054 3055 if (Visited.insert(SM).second) { 3056 Stack.push_back(SM); 3057 AnyChildren = true; 3058 } 3059 } 3060 3061 // We didn't find any children, so add this module to the list of 3062 // modules to link against. 3063 if (!AnyChildren) { 3064 LinkModules.insert(Mod); 3065 } 3066 } 3067 3068 // Add link options for all of the imported modules in reverse topological 3069 // order. We don't do anything to try to order import link flags with respect 3070 // to linker options inserted by things like #pragma comment(). 3071 SmallVector<llvm::MDNode *, 16> MetadataArgs; 3072 Visited.clear(); 3073 for (Module *M : LinkModules) 3074 if (Visited.insert(M).second) 3075 addLinkOptionsPostorder(*this, M, MetadataArgs, Visited); 3076 std::reverse(MetadataArgs.begin(), MetadataArgs.end()); 3077 LinkerOptionsMetadata.append(MetadataArgs.begin(), MetadataArgs.end()); 3078 3079 // Add the linker options metadata flag. 3080 auto *NMD = getModule().getOrInsertNamedMetadata("llvm.linker.options"); 3081 for (auto *MD : LinkerOptionsMetadata) 3082 NMD->addOperand(MD); 3083 } 3084 3085 void CodeGenModule::EmitDeferred() { 3086 // Emit deferred declare target declarations. 3087 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd) 3088 getOpenMPRuntime().emitDeferredTargetDecls(); 3089 3090 // Emit code for any potentially referenced deferred decls. Since a 3091 // previously unused static decl may become used during the generation of code 3092 // for a static function, iterate until no changes are made. 3093 3094 if (!DeferredVTables.empty()) { 3095 EmitDeferredVTables(); 3096 3097 // Emitting a vtable doesn't directly cause more vtables to 3098 // become deferred, although it can cause functions to be 3099 // emitted that then need those vtables. 3100 assert(DeferredVTables.empty()); 3101 } 3102 3103 // Emit CUDA/HIP static device variables referenced by host code only. 3104 // Note we should not clear CUDADeviceVarODRUsedByHost since it is still 3105 // needed for further handling. 3106 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) 3107 llvm::append_range(DeferredDeclsToEmit, 3108 getContext().CUDADeviceVarODRUsedByHost); 3109 3110 // Stop if we're out of both deferred vtables and deferred declarations. 3111 if (DeferredDeclsToEmit.empty()) 3112 return; 3113 3114 // Grab the list of decls to emit. If EmitGlobalDefinition schedules more 3115 // work, it will not interfere with this. 3116 std::vector<GlobalDecl> CurDeclsToEmit; 3117 CurDeclsToEmit.swap(DeferredDeclsToEmit); 3118 3119 for (GlobalDecl &D : CurDeclsToEmit) { 3120 // We should call GetAddrOfGlobal with IsForDefinition set to true in order 3121 // to get GlobalValue with exactly the type we need, not something that 3122 // might had been created for another decl with the same mangled name but 3123 // different type. 3124 llvm::GlobalValue *GV = dyn_cast<llvm::GlobalValue>( 3125 GetAddrOfGlobal(D, ForDefinition)); 3126 3127 // In case of different address spaces, we may still get a cast, even with 3128 // IsForDefinition equal to true. Query mangled names table to get 3129 // GlobalValue. 3130 if (!GV) 3131 GV = GetGlobalValue(getMangledName(D)); 3132 3133 // Make sure GetGlobalValue returned non-null. 3134 assert(GV); 3135 3136 // Check to see if we've already emitted this. This is necessary 3137 // for a couple of reasons: first, decls can end up in the 3138 // deferred-decls queue multiple times, and second, decls can end 3139 // up with definitions in unusual ways (e.g. by an extern inline 3140 // function acquiring a strong function redefinition). Just 3141 // ignore these cases. 3142 if (!GV->isDeclaration()) 3143 continue; 3144 3145 // If this is OpenMP, check if it is legal to emit this global normally. 3146 if (LangOpts.OpenMP && OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(D)) 3147 continue; 3148 3149 // Otherwise, emit the definition and move on to the next one. 3150 EmitGlobalDefinition(D, GV); 3151 3152 // If we found out that we need to emit more decls, do that recursively. 3153 // This has the advantage that the decls are emitted in a DFS and related 3154 // ones are close together, which is convenient for testing. 3155 if (!DeferredVTables.empty() || !DeferredDeclsToEmit.empty()) { 3156 EmitDeferred(); 3157 assert(DeferredVTables.empty() && DeferredDeclsToEmit.empty()); 3158 } 3159 } 3160 } 3161 3162 void CodeGenModule::EmitVTablesOpportunistically() { 3163 // Try to emit external vtables as available_externally if they have emitted 3164 // all inlined virtual functions. It runs after EmitDeferred() and therefore 3165 // is not allowed to create new references to things that need to be emitted 3166 // lazily. Note that it also uses fact that we eagerly emitting RTTI. 3167 3168 assert((OpportunisticVTables.empty() || shouldOpportunisticallyEmitVTables()) 3169 && "Only emit opportunistic vtables with optimizations"); 3170 3171 for (const CXXRecordDecl *RD : OpportunisticVTables) { 3172 assert(getVTables().isVTableExternal(RD) && 3173 "This queue should only contain external vtables"); 3174 if (getCXXABI().canSpeculativelyEmitVTable(RD)) 3175 VTables.GenerateClassData(RD); 3176 } 3177 OpportunisticVTables.clear(); 3178 } 3179 3180 void CodeGenModule::EmitGlobalAnnotations() { 3181 for (const auto& [MangledName, VD] : DeferredAnnotations) { 3182 llvm::GlobalValue *GV = GetGlobalValue(MangledName); 3183 if (GV) 3184 AddGlobalAnnotations(VD, GV); 3185 } 3186 DeferredAnnotations.clear(); 3187 3188 if (Annotations.empty()) 3189 return; 3190 3191 // Create a new global variable for the ConstantStruct in the Module. 3192 llvm::Constant *Array = llvm::ConstantArray::get(llvm::ArrayType::get( 3193 Annotations[0]->getType(), Annotations.size()), Annotations); 3194 auto *gv = new llvm::GlobalVariable(getModule(), Array->getType(), false, 3195 llvm::GlobalValue::AppendingLinkage, 3196 Array, "llvm.global.annotations"); 3197 gv->setSection(AnnotationSection); 3198 } 3199 3200 llvm::Constant *CodeGenModule::EmitAnnotationString(StringRef Str) { 3201 llvm::Constant *&AStr = AnnotationStrings[Str]; 3202 if (AStr) 3203 return AStr; 3204 3205 // Not found yet, create a new global. 3206 llvm::Constant *s = llvm::ConstantDataArray::getString(getLLVMContext(), Str); 3207 auto *gv = new llvm::GlobalVariable( 3208 getModule(), s->getType(), true, llvm::GlobalValue::PrivateLinkage, s, 3209 ".str", nullptr, llvm::GlobalValue::NotThreadLocal, 3210 ConstGlobalsPtrTy->getAddressSpace()); 3211 gv->setSection(AnnotationSection); 3212 gv->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3213 AStr = gv; 3214 return gv; 3215 } 3216 3217 llvm::Constant *CodeGenModule::EmitAnnotationUnit(SourceLocation Loc) { 3218 SourceManager &SM = getContext().getSourceManager(); 3219 PresumedLoc PLoc = SM.getPresumedLoc(Loc); 3220 if (PLoc.isValid()) 3221 return EmitAnnotationString(PLoc.getFilename()); 3222 return EmitAnnotationString(SM.getBufferName(Loc)); 3223 } 3224 3225 llvm::Constant *CodeGenModule::EmitAnnotationLineNo(SourceLocation L) { 3226 SourceManager &SM = getContext().getSourceManager(); 3227 PresumedLoc PLoc = SM.getPresumedLoc(L); 3228 unsigned LineNo = PLoc.isValid() ? PLoc.getLine() : 3229 SM.getExpansionLineNumber(L); 3230 return llvm::ConstantInt::get(Int32Ty, LineNo); 3231 } 3232 3233 llvm::Constant *CodeGenModule::EmitAnnotationArgs(const AnnotateAttr *Attr) { 3234 ArrayRef<Expr *> Exprs = {Attr->args_begin(), Attr->args_size()}; 3235 if (Exprs.empty()) 3236 return llvm::ConstantPointerNull::get(ConstGlobalsPtrTy); 3237 3238 llvm::FoldingSetNodeID ID; 3239 for (Expr *E : Exprs) { 3240 ID.Add(cast<clang::ConstantExpr>(E)->getAPValueResult()); 3241 } 3242 llvm::Constant *&Lookup = AnnotationArgs[ID.ComputeHash()]; 3243 if (Lookup) 3244 return Lookup; 3245 3246 llvm::SmallVector<llvm::Constant *, 4> LLVMArgs; 3247 LLVMArgs.reserve(Exprs.size()); 3248 ConstantEmitter ConstEmiter(*this); 3249 llvm::transform(Exprs, std::back_inserter(LLVMArgs), [&](const Expr *E) { 3250 const auto *CE = cast<clang::ConstantExpr>(E); 3251 return ConstEmiter.emitAbstract(CE->getBeginLoc(), CE->getAPValueResult(), 3252 CE->getType()); 3253 }); 3254 auto *Struct = llvm::ConstantStruct::getAnon(LLVMArgs); 3255 auto *GV = new llvm::GlobalVariable(getModule(), Struct->getType(), true, 3256 llvm::GlobalValue::PrivateLinkage, Struct, 3257 ".args"); 3258 GV->setSection(AnnotationSection); 3259 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3260 3261 Lookup = GV; 3262 return GV; 3263 } 3264 3265 llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV, 3266 const AnnotateAttr *AA, 3267 SourceLocation L) { 3268 // Get the globals for file name, annotation, and the line number. 3269 llvm::Constant *AnnoGV = EmitAnnotationString(AA->getAnnotation()), 3270 *UnitGV = EmitAnnotationUnit(L), 3271 *LineNoCst = EmitAnnotationLineNo(L), 3272 *Args = EmitAnnotationArgs(AA); 3273 3274 llvm::Constant *GVInGlobalsAS = GV; 3275 if (GV->getAddressSpace() != 3276 getDataLayout().getDefaultGlobalsAddressSpace()) { 3277 GVInGlobalsAS = llvm::ConstantExpr::getAddrSpaceCast( 3278 GV, 3279 llvm::PointerType::get( 3280 GV->getContext(), getDataLayout().getDefaultGlobalsAddressSpace())); 3281 } 3282 3283 // Create the ConstantStruct for the global annotation. 3284 llvm::Constant *Fields[] = { 3285 GVInGlobalsAS, AnnoGV, UnitGV, LineNoCst, Args, 3286 }; 3287 return llvm::ConstantStruct::getAnon(Fields); 3288 } 3289 3290 void CodeGenModule::AddGlobalAnnotations(const ValueDecl *D, 3291 llvm::GlobalValue *GV) { 3292 assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute"); 3293 // Get the struct elements for these annotations. 3294 for (const auto *I : D->specific_attrs<AnnotateAttr>()) 3295 Annotations.push_back(EmitAnnotateAttr(GV, I, D->getLocation())); 3296 } 3297 3298 bool CodeGenModule::isInNoSanitizeList(SanitizerMask Kind, llvm::Function *Fn, 3299 SourceLocation Loc) const { 3300 const auto &NoSanitizeL = getContext().getNoSanitizeList(); 3301 // NoSanitize by function name. 3302 if (NoSanitizeL.containsFunction(Kind, Fn->getName())) 3303 return true; 3304 // NoSanitize by location. Check "mainfile" prefix. 3305 auto &SM = Context.getSourceManager(); 3306 FileEntryRef MainFile = *SM.getFileEntryRefForID(SM.getMainFileID()); 3307 if (NoSanitizeL.containsMainFile(Kind, MainFile.getName())) 3308 return true; 3309 3310 // Check "src" prefix. 3311 if (Loc.isValid()) 3312 return NoSanitizeL.containsLocation(Kind, Loc); 3313 // If location is unknown, this may be a compiler-generated function. Assume 3314 // it's located in the main file. 3315 return NoSanitizeL.containsFile(Kind, MainFile.getName()); 3316 } 3317 3318 bool CodeGenModule::isInNoSanitizeList(SanitizerMask Kind, 3319 llvm::GlobalVariable *GV, 3320 SourceLocation Loc, QualType Ty, 3321 StringRef Category) const { 3322 const auto &NoSanitizeL = getContext().getNoSanitizeList(); 3323 if (NoSanitizeL.containsGlobal(Kind, GV->getName(), Category)) 3324 return true; 3325 auto &SM = Context.getSourceManager(); 3326 if (NoSanitizeL.containsMainFile( 3327 Kind, SM.getFileEntryRefForID(SM.getMainFileID())->getName(), 3328 Category)) 3329 return true; 3330 if (NoSanitizeL.containsLocation(Kind, Loc, Category)) 3331 return true; 3332 3333 // Check global type. 3334 if (!Ty.isNull()) { 3335 // Drill down the array types: if global variable of a fixed type is 3336 // not sanitized, we also don't instrument arrays of them. 3337 while (auto AT = dyn_cast<ArrayType>(Ty.getTypePtr())) 3338 Ty = AT->getElementType(); 3339 Ty = Ty.getCanonicalType().getUnqualifiedType(); 3340 // Only record types (classes, structs etc.) are ignored. 3341 if (Ty->isRecordType()) { 3342 std::string TypeStr = Ty.getAsString(getContext().getPrintingPolicy()); 3343 if (NoSanitizeL.containsType(Kind, TypeStr, Category)) 3344 return true; 3345 } 3346 } 3347 return false; 3348 } 3349 3350 bool CodeGenModule::imbueXRayAttrs(llvm::Function *Fn, SourceLocation Loc, 3351 StringRef Category) const { 3352 const auto &XRayFilter = getContext().getXRayFilter(); 3353 using ImbueAttr = XRayFunctionFilter::ImbueAttribute; 3354 auto Attr = ImbueAttr::NONE; 3355 if (Loc.isValid()) 3356 Attr = XRayFilter.shouldImbueLocation(Loc, Category); 3357 if (Attr == ImbueAttr::NONE) 3358 Attr = XRayFilter.shouldImbueFunction(Fn->getName()); 3359 switch (Attr) { 3360 case ImbueAttr::NONE: 3361 return false; 3362 case ImbueAttr::ALWAYS: 3363 Fn->addFnAttr("function-instrument", "xray-always"); 3364 break; 3365 case ImbueAttr::ALWAYS_ARG1: 3366 Fn->addFnAttr("function-instrument", "xray-always"); 3367 Fn->addFnAttr("xray-log-args", "1"); 3368 break; 3369 case ImbueAttr::NEVER: 3370 Fn->addFnAttr("function-instrument", "xray-never"); 3371 break; 3372 } 3373 return true; 3374 } 3375 3376 ProfileList::ExclusionType 3377 CodeGenModule::isFunctionBlockedByProfileList(llvm::Function *Fn, 3378 SourceLocation Loc) const { 3379 const auto &ProfileList = getContext().getProfileList(); 3380 // If the profile list is empty, then instrument everything. 3381 if (ProfileList.isEmpty()) 3382 return ProfileList::Allow; 3383 CodeGenOptions::ProfileInstrKind Kind = getCodeGenOpts().getProfileInstr(); 3384 // First, check the function name. 3385 if (auto V = ProfileList.isFunctionExcluded(Fn->getName(), Kind)) 3386 return *V; 3387 // Next, check the source location. 3388 if (Loc.isValid()) 3389 if (auto V = ProfileList.isLocationExcluded(Loc, Kind)) 3390 return *V; 3391 // If location is unknown, this may be a compiler-generated function. Assume 3392 // it's located in the main file. 3393 auto &SM = Context.getSourceManager(); 3394 if (auto MainFile = SM.getFileEntryRefForID(SM.getMainFileID())) 3395 if (auto V = ProfileList.isFileExcluded(MainFile->getName(), Kind)) 3396 return *V; 3397 return ProfileList.getDefault(Kind); 3398 } 3399 3400 ProfileList::ExclusionType 3401 CodeGenModule::isFunctionBlockedFromProfileInstr(llvm::Function *Fn, 3402 SourceLocation Loc) const { 3403 auto V = isFunctionBlockedByProfileList(Fn, Loc); 3404 if (V != ProfileList::Allow) 3405 return V; 3406 3407 auto NumGroups = getCodeGenOpts().ProfileTotalFunctionGroups; 3408 if (NumGroups > 1) { 3409 auto Group = llvm::crc32(arrayRefFromStringRef(Fn->getName())) % NumGroups; 3410 if (Group != getCodeGenOpts().ProfileSelectedFunctionGroup) 3411 return ProfileList::Skip; 3412 } 3413 return ProfileList::Allow; 3414 } 3415 3416 bool CodeGenModule::MustBeEmitted(const ValueDecl *Global) { 3417 // Never defer when EmitAllDecls is specified. 3418 if (LangOpts.EmitAllDecls) 3419 return true; 3420 3421 const auto *VD = dyn_cast<VarDecl>(Global); 3422 if (VD && 3423 ((CodeGenOpts.KeepPersistentStorageVariables && 3424 (VD->getStorageDuration() == SD_Static || 3425 VD->getStorageDuration() == SD_Thread)) || 3426 (CodeGenOpts.KeepStaticConsts && VD->getStorageDuration() == SD_Static && 3427 VD->getType().isConstQualified()))) 3428 return true; 3429 3430 return getContext().DeclMustBeEmitted(Global); 3431 } 3432 3433 bool CodeGenModule::MayBeEmittedEagerly(const ValueDecl *Global) { 3434 // In OpenMP 5.0 variables and function may be marked as 3435 // device_type(host/nohost) and we should not emit them eagerly unless we sure 3436 // that they must be emitted on the host/device. To be sure we need to have 3437 // seen a declare target with an explicit mentioning of the function, we know 3438 // we have if the level of the declare target attribute is -1. Note that we 3439 // check somewhere else if we should emit this at all. 3440 if (LangOpts.OpenMP >= 50 && !LangOpts.OpenMPSimd) { 3441 std::optional<OMPDeclareTargetDeclAttr *> ActiveAttr = 3442 OMPDeclareTargetDeclAttr::getActiveAttr(Global); 3443 if (!ActiveAttr || (*ActiveAttr)->getLevel() != (unsigned)-1) 3444 return false; 3445 } 3446 3447 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) { 3448 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 3449 // Implicit template instantiations may change linkage if they are later 3450 // explicitly instantiated, so they should not be emitted eagerly. 3451 return false; 3452 // Defer until all versions have been semantically checked. 3453 if (FD->hasAttr<TargetVersionAttr>() && !FD->isMultiVersion()) 3454 return false; 3455 } 3456 if (const auto *VD = dyn_cast<VarDecl>(Global)) { 3457 if (Context.getInlineVariableDefinitionKind(VD) == 3458 ASTContext::InlineVariableDefinitionKind::WeakUnknown) 3459 // A definition of an inline constexpr static data member may change 3460 // linkage later if it's redeclared outside the class. 3461 return false; 3462 if (CXX20ModuleInits && VD->getOwningModule() && 3463 !VD->getOwningModule()->isModuleMapModule()) { 3464 // For CXX20, module-owned initializers need to be deferred, since it is 3465 // not known at this point if they will be run for the current module or 3466 // as part of the initializer for an imported one. 3467 return false; 3468 } 3469 } 3470 // If OpenMP is enabled and threadprivates must be generated like TLS, delay 3471 // codegen for global variables, because they may be marked as threadprivate. 3472 if (LangOpts.OpenMP && LangOpts.OpenMPUseTLS && 3473 getContext().getTargetInfo().isTLSSupported() && isa<VarDecl>(Global) && 3474 !Global->getType().isConstantStorage(getContext(), false, false) && 3475 !OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(Global)) 3476 return false; 3477 3478 return true; 3479 } 3480 3481 ConstantAddress CodeGenModule::GetAddrOfMSGuidDecl(const MSGuidDecl *GD) { 3482 StringRef Name = getMangledName(GD); 3483 3484 // The UUID descriptor should be pointer aligned. 3485 CharUnits Alignment = CharUnits::fromQuantity(PointerAlignInBytes); 3486 3487 // Look for an existing global. 3488 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name)) 3489 return ConstantAddress(GV, GV->getValueType(), Alignment); 3490 3491 ConstantEmitter Emitter(*this); 3492 llvm::Constant *Init; 3493 3494 APValue &V = GD->getAsAPValue(); 3495 if (!V.isAbsent()) { 3496 // If possible, emit the APValue version of the initializer. In particular, 3497 // this gets the type of the constant right. 3498 Init = Emitter.emitForInitializer( 3499 GD->getAsAPValue(), GD->getType().getAddressSpace(), GD->getType()); 3500 } else { 3501 // As a fallback, directly construct the constant. 3502 // FIXME: This may get padding wrong under esoteric struct layout rules. 3503 // MSVC appears to create a complete type 'struct __s_GUID' that it 3504 // presumably uses to represent these constants. 3505 MSGuidDecl::Parts Parts = GD->getParts(); 3506 llvm::Constant *Fields[4] = { 3507 llvm::ConstantInt::get(Int32Ty, Parts.Part1), 3508 llvm::ConstantInt::get(Int16Ty, Parts.Part2), 3509 llvm::ConstantInt::get(Int16Ty, Parts.Part3), 3510 llvm::ConstantDataArray::getRaw( 3511 StringRef(reinterpret_cast<char *>(Parts.Part4And5), 8), 8, 3512 Int8Ty)}; 3513 Init = llvm::ConstantStruct::getAnon(Fields); 3514 } 3515 3516 auto *GV = new llvm::GlobalVariable( 3517 getModule(), Init->getType(), 3518 /*isConstant=*/true, llvm::GlobalValue::LinkOnceODRLinkage, Init, Name); 3519 if (supportsCOMDAT()) 3520 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 3521 setDSOLocal(GV); 3522 3523 if (!V.isAbsent()) { 3524 Emitter.finalize(GV); 3525 return ConstantAddress(GV, GV->getValueType(), Alignment); 3526 } 3527 3528 llvm::Type *Ty = getTypes().ConvertTypeForMem(GD->getType()); 3529 return ConstantAddress(GV, Ty, Alignment); 3530 } 3531 3532 ConstantAddress CodeGenModule::GetAddrOfUnnamedGlobalConstantDecl( 3533 const UnnamedGlobalConstantDecl *GCD) { 3534 CharUnits Alignment = getContext().getTypeAlignInChars(GCD->getType()); 3535 3536 llvm::GlobalVariable **Entry = nullptr; 3537 Entry = &UnnamedGlobalConstantDeclMap[GCD]; 3538 if (*Entry) 3539 return ConstantAddress(*Entry, (*Entry)->getValueType(), Alignment); 3540 3541 ConstantEmitter Emitter(*this); 3542 llvm::Constant *Init; 3543 3544 const APValue &V = GCD->getValue(); 3545 3546 assert(!V.isAbsent()); 3547 Init = Emitter.emitForInitializer(V, GCD->getType().getAddressSpace(), 3548 GCD->getType()); 3549 3550 auto *GV = new llvm::GlobalVariable(getModule(), Init->getType(), 3551 /*isConstant=*/true, 3552 llvm::GlobalValue::PrivateLinkage, Init, 3553 ".constant"); 3554 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3555 GV->setAlignment(Alignment.getAsAlign()); 3556 3557 Emitter.finalize(GV); 3558 3559 *Entry = GV; 3560 return ConstantAddress(GV, GV->getValueType(), Alignment); 3561 } 3562 3563 ConstantAddress CodeGenModule::GetAddrOfTemplateParamObject( 3564 const TemplateParamObjectDecl *TPO) { 3565 StringRef Name = getMangledName(TPO); 3566 CharUnits Alignment = getNaturalTypeAlignment(TPO->getType()); 3567 3568 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name)) 3569 return ConstantAddress(GV, GV->getValueType(), Alignment); 3570 3571 ConstantEmitter Emitter(*this); 3572 llvm::Constant *Init = Emitter.emitForInitializer( 3573 TPO->getValue(), TPO->getType().getAddressSpace(), TPO->getType()); 3574 3575 if (!Init) { 3576 ErrorUnsupported(TPO, "template parameter object"); 3577 return ConstantAddress::invalid(); 3578 } 3579 3580 llvm::GlobalValue::LinkageTypes Linkage = 3581 isExternallyVisible(TPO->getLinkageAndVisibility().getLinkage()) 3582 ? llvm::GlobalValue::LinkOnceODRLinkage 3583 : llvm::GlobalValue::InternalLinkage; 3584 auto *GV = new llvm::GlobalVariable(getModule(), Init->getType(), 3585 /*isConstant=*/true, Linkage, Init, Name); 3586 setGVProperties(GV, TPO); 3587 if (supportsCOMDAT()) 3588 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 3589 Emitter.finalize(GV); 3590 3591 return ConstantAddress(GV, GV->getValueType(), Alignment); 3592 } 3593 3594 ConstantAddress CodeGenModule::GetWeakRefReference(const ValueDecl *VD) { 3595 const AliasAttr *AA = VD->getAttr<AliasAttr>(); 3596 assert(AA && "No alias?"); 3597 3598 CharUnits Alignment = getContext().getDeclAlign(VD); 3599 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(VD->getType()); 3600 3601 // See if there is already something with the target's name in the module. 3602 llvm::GlobalValue *Entry = GetGlobalValue(AA->getAliasee()); 3603 if (Entry) 3604 return ConstantAddress(Entry, DeclTy, Alignment); 3605 3606 llvm::Constant *Aliasee; 3607 if (isa<llvm::FunctionType>(DeclTy)) 3608 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, 3609 GlobalDecl(cast<FunctionDecl>(VD)), 3610 /*ForVTable=*/false); 3611 else 3612 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, LangAS::Default, 3613 nullptr); 3614 3615 auto *F = cast<llvm::GlobalValue>(Aliasee); 3616 F->setLinkage(llvm::Function::ExternalWeakLinkage); 3617 WeakRefReferences.insert(F); 3618 3619 return ConstantAddress(Aliasee, DeclTy, Alignment); 3620 } 3621 3622 template <typename AttrT> static bool hasImplicitAttr(const ValueDecl *D) { 3623 if (!D) 3624 return false; 3625 if (auto *A = D->getAttr<AttrT>()) 3626 return A->isImplicit(); 3627 return D->isImplicit(); 3628 } 3629 3630 void CodeGenModule::EmitGlobal(GlobalDecl GD) { 3631 const auto *Global = cast<ValueDecl>(GD.getDecl()); 3632 3633 // Weak references don't produce any output by themselves. 3634 if (Global->hasAttr<WeakRefAttr>()) 3635 return; 3636 3637 // If this is an alias definition (which otherwise looks like a declaration) 3638 // emit it now. 3639 if (Global->hasAttr<AliasAttr>()) 3640 return EmitAliasDefinition(GD); 3641 3642 // IFunc like an alias whose value is resolved at runtime by calling resolver. 3643 if (Global->hasAttr<IFuncAttr>()) 3644 return emitIFuncDefinition(GD); 3645 3646 // If this is a cpu_dispatch multiversion function, emit the resolver. 3647 if (Global->hasAttr<CPUDispatchAttr>()) 3648 return emitCPUDispatchDefinition(GD); 3649 3650 // If this is CUDA, be selective about which declarations we emit. 3651 // Non-constexpr non-lambda implicit host device functions are not emitted 3652 // unless they are used on device side. 3653 if (LangOpts.CUDA) { 3654 if (LangOpts.CUDAIsDevice) { 3655 const auto *FD = dyn_cast<FunctionDecl>(Global); 3656 if ((!Global->hasAttr<CUDADeviceAttr>() || 3657 (LangOpts.OffloadImplicitHostDeviceTemplates && FD && 3658 hasImplicitAttr<CUDAHostAttr>(FD) && 3659 hasImplicitAttr<CUDADeviceAttr>(FD) && !FD->isConstexpr() && 3660 !isLambdaCallOperator(FD) && 3661 !getContext().CUDAImplicitHostDeviceFunUsedByDevice.count(FD))) && 3662 !Global->hasAttr<CUDAGlobalAttr>() && 3663 !Global->hasAttr<CUDAConstantAttr>() && 3664 !Global->hasAttr<CUDASharedAttr>() && 3665 !Global->getType()->isCUDADeviceBuiltinSurfaceType() && 3666 !Global->getType()->isCUDADeviceBuiltinTextureType() && 3667 !(LangOpts.HIPStdPar && isa<FunctionDecl>(Global) && 3668 !Global->hasAttr<CUDAHostAttr>())) 3669 return; 3670 } else { 3671 // We need to emit host-side 'shadows' for all global 3672 // device-side variables because the CUDA runtime needs their 3673 // size and host-side address in order to provide access to 3674 // their device-side incarnations. 3675 3676 // So device-only functions are the only things we skip. 3677 if (isa<FunctionDecl>(Global) && !Global->hasAttr<CUDAHostAttr>() && 3678 Global->hasAttr<CUDADeviceAttr>()) 3679 return; 3680 3681 assert((isa<FunctionDecl>(Global) || isa<VarDecl>(Global)) && 3682 "Expected Variable or Function"); 3683 } 3684 } 3685 3686 if (LangOpts.OpenMP) { 3687 // If this is OpenMP, check if it is legal to emit this global normally. 3688 if (OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(GD)) 3689 return; 3690 if (auto *DRD = dyn_cast<OMPDeclareReductionDecl>(Global)) { 3691 if (MustBeEmitted(Global)) 3692 EmitOMPDeclareReduction(DRD); 3693 return; 3694 } 3695 if (auto *DMD = dyn_cast<OMPDeclareMapperDecl>(Global)) { 3696 if (MustBeEmitted(Global)) 3697 EmitOMPDeclareMapper(DMD); 3698 return; 3699 } 3700 } 3701 3702 // Ignore declarations, they will be emitted on their first use. 3703 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) { 3704 // Update deferred annotations with the latest declaration if the function 3705 // function was already used or defined. 3706 if (FD->hasAttr<AnnotateAttr>()) { 3707 StringRef MangledName = getMangledName(GD); 3708 if (GetGlobalValue(MangledName)) 3709 DeferredAnnotations[MangledName] = FD; 3710 } 3711 3712 // Forward declarations are emitted lazily on first use. 3713 if (!FD->doesThisDeclarationHaveABody()) { 3714 if (!FD->doesDeclarationForceExternallyVisibleDefinition() && 3715 (!FD->isMultiVersion() || 3716 !FD->getASTContext().getTargetInfo().getTriple().isAArch64())) 3717 return; 3718 3719 StringRef MangledName = getMangledName(GD); 3720 3721 // Compute the function info and LLVM type. 3722 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 3723 llvm::Type *Ty = getTypes().GetFunctionType(FI); 3724 3725 GetOrCreateLLVMFunction(MangledName, Ty, GD, /*ForVTable=*/false, 3726 /*DontDefer=*/false); 3727 return; 3728 } 3729 } else { 3730 const auto *VD = cast<VarDecl>(Global); 3731 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global."); 3732 if (VD->isThisDeclarationADefinition() != VarDecl::Definition && 3733 !Context.isMSStaticDataMemberInlineDefinition(VD)) { 3734 if (LangOpts.OpenMP) { 3735 // Emit declaration of the must-be-emitted declare target variable. 3736 if (std::optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res = 3737 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD)) { 3738 3739 // If this variable has external storage and doesn't require special 3740 // link handling we defer to its canonical definition. 3741 if (VD->hasExternalStorage() && 3742 Res != OMPDeclareTargetDeclAttr::MT_Link) 3743 return; 3744 3745 bool UnifiedMemoryEnabled = 3746 getOpenMPRuntime().hasRequiresUnifiedSharedMemory(); 3747 if ((*Res == OMPDeclareTargetDeclAttr::MT_To || 3748 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 3749 !UnifiedMemoryEnabled) { 3750 (void)GetAddrOfGlobalVar(VD); 3751 } else { 3752 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) || 3753 ((*Res == OMPDeclareTargetDeclAttr::MT_To || 3754 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 3755 UnifiedMemoryEnabled)) && 3756 "Link clause or to clause with unified memory expected."); 3757 (void)getOpenMPRuntime().getAddrOfDeclareTargetVar(VD); 3758 } 3759 3760 return; 3761 } 3762 } 3763 // If this declaration may have caused an inline variable definition to 3764 // change linkage, make sure that it's emitted. 3765 if (Context.getInlineVariableDefinitionKind(VD) == 3766 ASTContext::InlineVariableDefinitionKind::Strong) 3767 GetAddrOfGlobalVar(VD); 3768 return; 3769 } 3770 } 3771 3772 // Defer code generation to first use when possible, e.g. if this is an inline 3773 // function. If the global must always be emitted, do it eagerly if possible 3774 // to benefit from cache locality. 3775 if (MustBeEmitted(Global) && MayBeEmittedEagerly(Global)) { 3776 // Emit the definition if it can't be deferred. 3777 EmitGlobalDefinition(GD); 3778 addEmittedDeferredDecl(GD); 3779 return; 3780 } 3781 3782 // If we're deferring emission of a C++ variable with an 3783 // initializer, remember the order in which it appeared in the file. 3784 if (getLangOpts().CPlusPlus && isa<VarDecl>(Global) && 3785 cast<VarDecl>(Global)->hasInit()) { 3786 DelayedCXXInitPosition[Global] = CXXGlobalInits.size(); 3787 CXXGlobalInits.push_back(nullptr); 3788 } 3789 3790 StringRef MangledName = getMangledName(GD); 3791 if (GetGlobalValue(MangledName) != nullptr) { 3792 // The value has already been used and should therefore be emitted. 3793 addDeferredDeclToEmit(GD); 3794 } else if (MustBeEmitted(Global)) { 3795 // The value must be emitted, but cannot be emitted eagerly. 3796 assert(!MayBeEmittedEagerly(Global)); 3797 addDeferredDeclToEmit(GD); 3798 } else { 3799 // Otherwise, remember that we saw a deferred decl with this name. The 3800 // first use of the mangled name will cause it to move into 3801 // DeferredDeclsToEmit. 3802 DeferredDecls[MangledName] = GD; 3803 } 3804 } 3805 3806 // Check if T is a class type with a destructor that's not dllimport. 3807 static bool HasNonDllImportDtor(QualType T) { 3808 if (const auto *RT = T->getBaseElementTypeUnsafe()->getAs<RecordType>()) 3809 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) 3810 if (RD->getDestructor() && !RD->getDestructor()->hasAttr<DLLImportAttr>()) 3811 return true; 3812 3813 return false; 3814 } 3815 3816 namespace { 3817 struct FunctionIsDirectlyRecursive 3818 : public ConstStmtVisitor<FunctionIsDirectlyRecursive, bool> { 3819 const StringRef Name; 3820 const Builtin::Context &BI; 3821 FunctionIsDirectlyRecursive(StringRef N, const Builtin::Context &C) 3822 : Name(N), BI(C) {} 3823 3824 bool VisitCallExpr(const CallExpr *E) { 3825 const FunctionDecl *FD = E->getDirectCallee(); 3826 if (!FD) 3827 return false; 3828 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>(); 3829 if (Attr && Name == Attr->getLabel()) 3830 return true; 3831 unsigned BuiltinID = FD->getBuiltinID(); 3832 if (!BuiltinID || !BI.isLibFunction(BuiltinID)) 3833 return false; 3834 StringRef BuiltinName = BI.getName(BuiltinID); 3835 if (BuiltinName.starts_with("__builtin_") && 3836 Name == BuiltinName.slice(strlen("__builtin_"), StringRef::npos)) { 3837 return true; 3838 } 3839 return false; 3840 } 3841 3842 bool VisitStmt(const Stmt *S) { 3843 for (const Stmt *Child : S->children()) 3844 if (Child && this->Visit(Child)) 3845 return true; 3846 return false; 3847 } 3848 }; 3849 3850 // Make sure we're not referencing non-imported vars or functions. 3851 struct DLLImportFunctionVisitor 3852 : public RecursiveASTVisitor<DLLImportFunctionVisitor> { 3853 bool SafeToInline = true; 3854 3855 bool shouldVisitImplicitCode() const { return true; } 3856 3857 bool VisitVarDecl(VarDecl *VD) { 3858 if (VD->getTLSKind()) { 3859 // A thread-local variable cannot be imported. 3860 SafeToInline = false; 3861 return SafeToInline; 3862 } 3863 3864 // A variable definition might imply a destructor call. 3865 if (VD->isThisDeclarationADefinition()) 3866 SafeToInline = !HasNonDllImportDtor(VD->getType()); 3867 3868 return SafeToInline; 3869 } 3870 3871 bool VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { 3872 if (const auto *D = E->getTemporary()->getDestructor()) 3873 SafeToInline = D->hasAttr<DLLImportAttr>(); 3874 return SafeToInline; 3875 } 3876 3877 bool VisitDeclRefExpr(DeclRefExpr *E) { 3878 ValueDecl *VD = E->getDecl(); 3879 if (isa<FunctionDecl>(VD)) 3880 SafeToInline = VD->hasAttr<DLLImportAttr>(); 3881 else if (VarDecl *V = dyn_cast<VarDecl>(VD)) 3882 SafeToInline = !V->hasGlobalStorage() || V->hasAttr<DLLImportAttr>(); 3883 return SafeToInline; 3884 } 3885 3886 bool VisitCXXConstructExpr(CXXConstructExpr *E) { 3887 SafeToInline = E->getConstructor()->hasAttr<DLLImportAttr>(); 3888 return SafeToInline; 3889 } 3890 3891 bool VisitCXXMemberCallExpr(CXXMemberCallExpr *E) { 3892 CXXMethodDecl *M = E->getMethodDecl(); 3893 if (!M) { 3894 // Call through a pointer to member function. This is safe to inline. 3895 SafeToInline = true; 3896 } else { 3897 SafeToInline = M->hasAttr<DLLImportAttr>(); 3898 } 3899 return SafeToInline; 3900 } 3901 3902 bool VisitCXXDeleteExpr(CXXDeleteExpr *E) { 3903 SafeToInline = E->getOperatorDelete()->hasAttr<DLLImportAttr>(); 3904 return SafeToInline; 3905 } 3906 3907 bool VisitCXXNewExpr(CXXNewExpr *E) { 3908 SafeToInline = E->getOperatorNew()->hasAttr<DLLImportAttr>(); 3909 return SafeToInline; 3910 } 3911 }; 3912 } 3913 3914 // isTriviallyRecursive - Check if this function calls another 3915 // decl that, because of the asm attribute or the other decl being a builtin, 3916 // ends up pointing to itself. 3917 bool 3918 CodeGenModule::isTriviallyRecursive(const FunctionDecl *FD) { 3919 StringRef Name; 3920 if (getCXXABI().getMangleContext().shouldMangleDeclName(FD)) { 3921 // asm labels are a special kind of mangling we have to support. 3922 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>(); 3923 if (!Attr) 3924 return false; 3925 Name = Attr->getLabel(); 3926 } else { 3927 Name = FD->getName(); 3928 } 3929 3930 FunctionIsDirectlyRecursive Walker(Name, Context.BuiltinInfo); 3931 const Stmt *Body = FD->getBody(); 3932 return Body ? Walker.Visit(Body) : false; 3933 } 3934 3935 bool CodeGenModule::shouldEmitFunction(GlobalDecl GD) { 3936 if (getFunctionLinkage(GD) != llvm::Function::AvailableExternallyLinkage) 3937 return true; 3938 3939 const auto *F = cast<FunctionDecl>(GD.getDecl()); 3940 if (CodeGenOpts.OptimizationLevel == 0 && !F->hasAttr<AlwaysInlineAttr>()) 3941 return false; 3942 3943 // We don't import function bodies from other named module units since that 3944 // behavior may break ABI compatibility of the current unit. 3945 if (const Module *M = F->getOwningModule(); 3946 M && M->getTopLevelModule()->isNamedModule() && 3947 getContext().getCurrentNamedModule() != M->getTopLevelModule()) 3948 return false; 3949 3950 if (F->hasAttr<NoInlineAttr>()) 3951 return false; 3952 3953 if (F->hasAttr<DLLImportAttr>() && !F->hasAttr<AlwaysInlineAttr>()) { 3954 // Check whether it would be safe to inline this dllimport function. 3955 DLLImportFunctionVisitor Visitor; 3956 Visitor.TraverseFunctionDecl(const_cast<FunctionDecl*>(F)); 3957 if (!Visitor.SafeToInline) 3958 return false; 3959 3960 if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(F)) { 3961 // Implicit destructor invocations aren't captured in the AST, so the 3962 // check above can't see them. Check for them manually here. 3963 for (const Decl *Member : Dtor->getParent()->decls()) 3964 if (isa<FieldDecl>(Member)) 3965 if (HasNonDllImportDtor(cast<FieldDecl>(Member)->getType())) 3966 return false; 3967 for (const CXXBaseSpecifier &B : Dtor->getParent()->bases()) 3968 if (HasNonDllImportDtor(B.getType())) 3969 return false; 3970 } 3971 } 3972 3973 // Inline builtins declaration must be emitted. They often are fortified 3974 // functions. 3975 if (F->isInlineBuiltinDeclaration()) 3976 return true; 3977 3978 // PR9614. Avoid cases where the source code is lying to us. An available 3979 // externally function should have an equivalent function somewhere else, 3980 // but a function that calls itself through asm label/`__builtin_` trickery is 3981 // clearly not equivalent to the real implementation. 3982 // This happens in glibc's btowc and in some configure checks. 3983 return !isTriviallyRecursive(F); 3984 } 3985 3986 bool CodeGenModule::shouldOpportunisticallyEmitVTables() { 3987 return CodeGenOpts.OptimizationLevel > 0; 3988 } 3989 3990 void CodeGenModule::EmitMultiVersionFunctionDefinition(GlobalDecl GD, 3991 llvm::GlobalValue *GV) { 3992 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 3993 3994 if (FD->isCPUSpecificMultiVersion()) { 3995 auto *Spec = FD->getAttr<CPUSpecificAttr>(); 3996 for (unsigned I = 0; I < Spec->cpus_size(); ++I) 3997 EmitGlobalFunctionDefinition(GD.getWithMultiVersionIndex(I), nullptr); 3998 } else if (auto *TC = FD->getAttr<TargetClonesAttr>()) { 3999 for (unsigned I = 0; I < TC->featuresStrs_size(); ++I) 4000 // AArch64 favors the default target version over the clone if any. 4001 if ((!TC->isDefaultVersion(I) || !getTarget().getTriple().isAArch64()) && 4002 TC->isFirstOfVersion(I)) 4003 EmitGlobalFunctionDefinition(GD.getWithMultiVersionIndex(I), nullptr); 4004 // Ensure that the resolver function is also emitted. 4005 GetOrCreateMultiVersionResolver(GD); 4006 } else 4007 EmitGlobalFunctionDefinition(GD, GV); 4008 4009 // Defer the resolver emission until we can reason whether the TU 4010 // contains a default target version implementation. 4011 if (FD->isTargetVersionMultiVersion()) 4012 AddDeferredMultiVersionResolverToEmit(GD); 4013 } 4014 4015 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD, llvm::GlobalValue *GV) { 4016 const auto *D = cast<ValueDecl>(GD.getDecl()); 4017 4018 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(), 4019 Context.getSourceManager(), 4020 "Generating code for declaration"); 4021 4022 if (const auto *FD = dyn_cast<FunctionDecl>(D)) { 4023 // At -O0, don't generate IR for functions with available_externally 4024 // linkage. 4025 if (!shouldEmitFunction(GD)) 4026 return; 4027 4028 llvm::TimeTraceScope TimeScope("CodeGen Function", [&]() { 4029 std::string Name; 4030 llvm::raw_string_ostream OS(Name); 4031 FD->getNameForDiagnostic(OS, getContext().getPrintingPolicy(), 4032 /*Qualified=*/true); 4033 return Name; 4034 }); 4035 4036 if (const auto *Method = dyn_cast<CXXMethodDecl>(D)) { 4037 // Make sure to emit the definition(s) before we emit the thunks. 4038 // This is necessary for the generation of certain thunks. 4039 if (isa<CXXConstructorDecl>(Method) || isa<CXXDestructorDecl>(Method)) 4040 ABI->emitCXXStructor(GD); 4041 else if (FD->isMultiVersion()) 4042 EmitMultiVersionFunctionDefinition(GD, GV); 4043 else 4044 EmitGlobalFunctionDefinition(GD, GV); 4045 4046 if (Method->isVirtual()) 4047 getVTables().EmitThunks(GD); 4048 4049 return; 4050 } 4051 4052 if (FD->isMultiVersion()) 4053 return EmitMultiVersionFunctionDefinition(GD, GV); 4054 return EmitGlobalFunctionDefinition(GD, GV); 4055 } 4056 4057 if (const auto *VD = dyn_cast<VarDecl>(D)) 4058 return EmitGlobalVarDefinition(VD, !VD->hasDefinition()); 4059 4060 llvm_unreachable("Invalid argument to EmitGlobalDefinition()"); 4061 } 4062 4063 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 4064 llvm::Function *NewFn); 4065 4066 static unsigned 4067 TargetMVPriority(const TargetInfo &TI, 4068 const CodeGenFunction::MultiVersionResolverOption &RO) { 4069 unsigned Priority = 0; 4070 unsigned NumFeatures = 0; 4071 for (StringRef Feat : RO.Conditions.Features) { 4072 Priority = std::max(Priority, TI.multiVersionSortPriority(Feat)); 4073 NumFeatures++; 4074 } 4075 4076 if (!RO.Conditions.Architecture.empty()) 4077 Priority = std::max( 4078 Priority, TI.multiVersionSortPriority(RO.Conditions.Architecture)); 4079 4080 Priority += TI.multiVersionFeatureCost() * NumFeatures; 4081 4082 return Priority; 4083 } 4084 4085 // Multiversion functions should be at most 'WeakODRLinkage' so that a different 4086 // TU can forward declare the function without causing problems. Particularly 4087 // in the cases of CPUDispatch, this causes issues. This also makes sure we 4088 // work with internal linkage functions, so that the same function name can be 4089 // used with internal linkage in multiple TUs. 4090 llvm::GlobalValue::LinkageTypes getMultiversionLinkage(CodeGenModule &CGM, 4091 GlobalDecl GD) { 4092 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 4093 if (FD->getFormalLinkage() == Linkage::Internal) 4094 return llvm::GlobalValue::InternalLinkage; 4095 return llvm::GlobalValue::WeakODRLinkage; 4096 } 4097 4098 static FunctionDecl *createDefaultTargetVersionFrom(const FunctionDecl *FD) { 4099 DeclContext *DeclCtx = FD->getASTContext().getTranslationUnitDecl(); 4100 TypeSourceInfo *TInfo = FD->getTypeSourceInfo(); 4101 StorageClass SC = FD->getStorageClass(); 4102 DeclarationName Name = FD->getNameInfo().getName(); 4103 4104 FunctionDecl *NewDecl = 4105 FunctionDecl::Create(FD->getASTContext(), DeclCtx, FD->getBeginLoc(), 4106 FD->getEndLoc(), Name, TInfo->getType(), TInfo, SC); 4107 4108 NewDecl->setIsMultiVersion(); 4109 NewDecl->addAttr(TargetVersionAttr::CreateImplicit( 4110 NewDecl->getASTContext(), "default", NewDecl->getSourceRange())); 4111 4112 return NewDecl; 4113 } 4114 4115 void CodeGenModule::emitMultiVersionFunctions() { 4116 std::vector<GlobalDecl> MVFuncsToEmit; 4117 MultiVersionFuncs.swap(MVFuncsToEmit); 4118 for (GlobalDecl GD : MVFuncsToEmit) { 4119 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4120 assert(FD && "Expected a FunctionDecl"); 4121 4122 auto createFunction = [&](const FunctionDecl *Decl, unsigned MVIdx = 0) { 4123 GlobalDecl CurGD{Decl->isDefined() ? Decl->getDefinition() : Decl, MVIdx}; 4124 StringRef MangledName = getMangledName(CurGD); 4125 llvm::Constant *Func = GetGlobalValue(MangledName); 4126 if (!Func) { 4127 if (Decl->isDefined()) { 4128 EmitGlobalFunctionDefinition(CurGD, nullptr); 4129 Func = GetGlobalValue(MangledName); 4130 } else { 4131 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(CurGD); 4132 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 4133 Func = GetAddrOfFunction(CurGD, Ty, /*ForVTable=*/false, 4134 /*DontDefer=*/false, ForDefinition); 4135 } 4136 assert(Func && "This should have just been created"); 4137 } 4138 return cast<llvm::Function>(Func); 4139 }; 4140 4141 bool HasDefaultDecl = !FD->isTargetVersionMultiVersion(); 4142 bool ShouldEmitResolver = 4143 !getContext().getTargetInfo().getTriple().isAArch64(); 4144 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options; 4145 4146 getContext().forEachMultiversionedFunctionVersion( 4147 FD, [&](const FunctionDecl *CurFD) { 4148 llvm::SmallVector<StringRef, 8> Feats; 4149 4150 if (const auto *TA = CurFD->getAttr<TargetAttr>()) { 4151 TA->getAddedFeatures(Feats); 4152 llvm::Function *Func = createFunction(CurFD); 4153 Options.emplace_back(Func, TA->getArchitecture(), Feats); 4154 } else if (const auto *TVA = CurFD->getAttr<TargetVersionAttr>()) { 4155 bool HasDefaultDef = TVA->isDefaultVersion() && 4156 CurFD->doesThisDeclarationHaveABody(); 4157 HasDefaultDecl |= TVA->isDefaultVersion(); 4158 ShouldEmitResolver |= (CurFD->isUsed() || HasDefaultDef); 4159 TVA->getFeatures(Feats); 4160 llvm::Function *Func = createFunction(CurFD); 4161 Options.emplace_back(Func, /*Architecture*/ "", Feats); 4162 } else if (const auto *TC = CurFD->getAttr<TargetClonesAttr>()) { 4163 ShouldEmitResolver |= CurFD->doesThisDeclarationHaveABody(); 4164 for (unsigned I = 0; I < TC->featuresStrs_size(); ++I) { 4165 if (!TC->isFirstOfVersion(I)) 4166 continue; 4167 4168 llvm::Function *Func = createFunction(CurFD, I); 4169 StringRef Architecture; 4170 Feats.clear(); 4171 if (getTarget().getTriple().isAArch64()) 4172 TC->getFeatures(Feats, I); 4173 else { 4174 StringRef Version = TC->getFeatureStr(I); 4175 if (Version.starts_with("arch=")) 4176 Architecture = Version.drop_front(sizeof("arch=") - 1); 4177 else if (Version != "default") 4178 Feats.push_back(Version); 4179 } 4180 Options.emplace_back(Func, Architecture, Feats); 4181 } 4182 } else 4183 llvm_unreachable("unexpected MultiVersionKind"); 4184 }); 4185 4186 if (!ShouldEmitResolver) 4187 continue; 4188 4189 if (!HasDefaultDecl) { 4190 FunctionDecl *NewFD = createDefaultTargetVersionFrom(FD); 4191 llvm::Function *Func = createFunction(NewFD); 4192 llvm::SmallVector<StringRef, 1> Feats; 4193 Options.emplace_back(Func, /*Architecture*/ "", Feats); 4194 } 4195 4196 llvm::Constant *ResolverConstant = GetOrCreateMultiVersionResolver(GD); 4197 if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(ResolverConstant)) { 4198 ResolverConstant = IFunc->getResolver(); 4199 if (FD->isTargetClonesMultiVersion() || 4200 FD->isTargetVersionMultiVersion()) { 4201 std::string MangledName = getMangledNameImpl( 4202 *this, GD, FD, /*OmitMultiVersionMangling=*/true); 4203 if (!GetGlobalValue(MangledName + ".ifunc")) { 4204 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4205 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI); 4206 // In prior versions of Clang, the mangling for ifuncs incorrectly 4207 // included an .ifunc suffix. This alias is generated for backward 4208 // compatibility. It is deprecated, and may be removed in the future. 4209 auto *Alias = llvm::GlobalAlias::create( 4210 DeclTy, 0, getMultiversionLinkage(*this, GD), 4211 MangledName + ".ifunc", IFunc, &getModule()); 4212 SetCommonAttributes(FD, Alias); 4213 } 4214 } 4215 } 4216 llvm::Function *ResolverFunc = cast<llvm::Function>(ResolverConstant); 4217 4218 ResolverFunc->setLinkage(getMultiversionLinkage(*this, GD)); 4219 4220 if (!ResolverFunc->hasLocalLinkage() && supportsCOMDAT()) 4221 ResolverFunc->setComdat( 4222 getModule().getOrInsertComdat(ResolverFunc->getName())); 4223 4224 const TargetInfo &TI = getTarget(); 4225 llvm::stable_sort( 4226 Options, [&TI](const CodeGenFunction::MultiVersionResolverOption &LHS, 4227 const CodeGenFunction::MultiVersionResolverOption &RHS) { 4228 return TargetMVPriority(TI, LHS) > TargetMVPriority(TI, RHS); 4229 }); 4230 CodeGenFunction CGF(*this); 4231 CGF.EmitMultiVersionResolver(ResolverFunc, Options); 4232 } 4233 4234 // Ensure that any additions to the deferred decls list caused by emitting a 4235 // variant are emitted. This can happen when the variant itself is inline and 4236 // calls a function without linkage. 4237 if (!MVFuncsToEmit.empty()) 4238 EmitDeferred(); 4239 4240 // Ensure that any additions to the multiversion funcs list from either the 4241 // deferred decls or the multiversion functions themselves are emitted. 4242 if (!MultiVersionFuncs.empty()) 4243 emitMultiVersionFunctions(); 4244 } 4245 4246 void CodeGenModule::emitCPUDispatchDefinition(GlobalDecl GD) { 4247 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4248 assert(FD && "Not a FunctionDecl?"); 4249 assert(FD->isCPUDispatchMultiVersion() && "Not a multiversion function?"); 4250 const auto *DD = FD->getAttr<CPUDispatchAttr>(); 4251 assert(DD && "Not a cpu_dispatch Function?"); 4252 4253 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4254 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI); 4255 4256 StringRef ResolverName = getMangledName(GD); 4257 UpdateMultiVersionNames(GD, FD, ResolverName); 4258 4259 llvm::Type *ResolverType; 4260 GlobalDecl ResolverGD; 4261 if (getTarget().supportsIFunc()) { 4262 ResolverType = llvm::FunctionType::get( 4263 llvm::PointerType::get(DeclTy, 4264 getTypes().getTargetAddressSpace(FD->getType())), 4265 false); 4266 } 4267 else { 4268 ResolverType = DeclTy; 4269 ResolverGD = GD; 4270 } 4271 4272 auto *ResolverFunc = cast<llvm::Function>(GetOrCreateLLVMFunction( 4273 ResolverName, ResolverType, ResolverGD, /*ForVTable=*/false)); 4274 ResolverFunc->setLinkage(getMultiversionLinkage(*this, GD)); 4275 if (supportsCOMDAT()) 4276 ResolverFunc->setComdat( 4277 getModule().getOrInsertComdat(ResolverFunc->getName())); 4278 4279 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options; 4280 const TargetInfo &Target = getTarget(); 4281 unsigned Index = 0; 4282 for (const IdentifierInfo *II : DD->cpus()) { 4283 // Get the name of the target function so we can look it up/create it. 4284 std::string MangledName = getMangledNameImpl(*this, GD, FD, true) + 4285 getCPUSpecificMangling(*this, II->getName()); 4286 4287 llvm::Constant *Func = GetGlobalValue(MangledName); 4288 4289 if (!Func) { 4290 GlobalDecl ExistingDecl = Manglings.lookup(MangledName); 4291 if (ExistingDecl.getDecl() && 4292 ExistingDecl.getDecl()->getAsFunction()->isDefined()) { 4293 EmitGlobalFunctionDefinition(ExistingDecl, nullptr); 4294 Func = GetGlobalValue(MangledName); 4295 } else { 4296 if (!ExistingDecl.getDecl()) 4297 ExistingDecl = GD.getWithMultiVersionIndex(Index); 4298 4299 Func = GetOrCreateLLVMFunction( 4300 MangledName, DeclTy, ExistingDecl, 4301 /*ForVTable=*/false, /*DontDefer=*/true, 4302 /*IsThunk=*/false, llvm::AttributeList(), ForDefinition); 4303 } 4304 } 4305 4306 llvm::SmallVector<StringRef, 32> Features; 4307 Target.getCPUSpecificCPUDispatchFeatures(II->getName(), Features); 4308 llvm::transform(Features, Features.begin(), 4309 [](StringRef Str) { return Str.substr(1); }); 4310 llvm::erase_if(Features, [&Target](StringRef Feat) { 4311 return !Target.validateCpuSupports(Feat); 4312 }); 4313 Options.emplace_back(cast<llvm::Function>(Func), StringRef{}, Features); 4314 ++Index; 4315 } 4316 4317 llvm::stable_sort( 4318 Options, [](const CodeGenFunction::MultiVersionResolverOption &LHS, 4319 const CodeGenFunction::MultiVersionResolverOption &RHS) { 4320 return llvm::X86::getCpuSupportsMask(LHS.Conditions.Features) > 4321 llvm::X86::getCpuSupportsMask(RHS.Conditions.Features); 4322 }); 4323 4324 // If the list contains multiple 'default' versions, such as when it contains 4325 // 'pentium' and 'generic', don't emit the call to the generic one (since we 4326 // always run on at least a 'pentium'). We do this by deleting the 'least 4327 // advanced' (read, lowest mangling letter). 4328 while (Options.size() > 1 && 4329 llvm::all_of(llvm::X86::getCpuSupportsMask( 4330 (Options.end() - 2)->Conditions.Features), 4331 [](auto X) { return X == 0; })) { 4332 StringRef LHSName = (Options.end() - 2)->Function->getName(); 4333 StringRef RHSName = (Options.end() - 1)->Function->getName(); 4334 if (LHSName.compare(RHSName) < 0) 4335 Options.erase(Options.end() - 2); 4336 else 4337 Options.erase(Options.end() - 1); 4338 } 4339 4340 CodeGenFunction CGF(*this); 4341 CGF.EmitMultiVersionResolver(ResolverFunc, Options); 4342 4343 if (getTarget().supportsIFunc()) { 4344 llvm::GlobalValue::LinkageTypes Linkage = getMultiversionLinkage(*this, GD); 4345 auto *IFunc = cast<llvm::GlobalValue>(GetOrCreateMultiVersionResolver(GD)); 4346 4347 // Fix up function declarations that were created for cpu_specific before 4348 // cpu_dispatch was known 4349 if (!isa<llvm::GlobalIFunc>(IFunc)) { 4350 assert(cast<llvm::Function>(IFunc)->isDeclaration()); 4351 auto *GI = llvm::GlobalIFunc::create(DeclTy, 0, Linkage, "", ResolverFunc, 4352 &getModule()); 4353 GI->takeName(IFunc); 4354 IFunc->replaceAllUsesWith(GI); 4355 IFunc->eraseFromParent(); 4356 IFunc = GI; 4357 } 4358 4359 std::string AliasName = getMangledNameImpl( 4360 *this, GD, FD, /*OmitMultiVersionMangling=*/true); 4361 llvm::Constant *AliasFunc = GetGlobalValue(AliasName); 4362 if (!AliasFunc) { 4363 auto *GA = llvm::GlobalAlias::create(DeclTy, 0, Linkage, AliasName, IFunc, 4364 &getModule()); 4365 SetCommonAttributes(GD, GA); 4366 } 4367 } 4368 } 4369 4370 /// Adds a declaration to the list of multi version functions if not present. 4371 void CodeGenModule::AddDeferredMultiVersionResolverToEmit(GlobalDecl GD) { 4372 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4373 assert(FD && "Not a FunctionDecl?"); 4374 4375 if (FD->isTargetVersionMultiVersion() || FD->isTargetClonesMultiVersion()) { 4376 std::string MangledName = 4377 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true); 4378 if (!DeferredResolversToEmit.insert(MangledName).second) 4379 return; 4380 } 4381 MultiVersionFuncs.push_back(GD); 4382 } 4383 4384 /// If a dispatcher for the specified mangled name is not in the module, create 4385 /// and return an llvm Function with the specified type. 4386 llvm::Constant *CodeGenModule::GetOrCreateMultiVersionResolver(GlobalDecl GD) { 4387 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4388 assert(FD && "Not a FunctionDecl?"); 4389 4390 std::string MangledName = 4391 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true); 4392 4393 // Holds the name of the resolver, in ifunc mode this is the ifunc (which has 4394 // a separate resolver). 4395 std::string ResolverName = MangledName; 4396 if (getTarget().supportsIFunc()) { 4397 switch (FD->getMultiVersionKind()) { 4398 case MultiVersionKind::None: 4399 llvm_unreachable("unexpected MultiVersionKind::None for resolver"); 4400 case MultiVersionKind::Target: 4401 case MultiVersionKind::CPUSpecific: 4402 case MultiVersionKind::CPUDispatch: 4403 ResolverName += ".ifunc"; 4404 break; 4405 case MultiVersionKind::TargetClones: 4406 case MultiVersionKind::TargetVersion: 4407 break; 4408 } 4409 } else if (FD->isTargetMultiVersion()) { 4410 ResolverName += ".resolver"; 4411 } 4412 4413 // If the resolver has already been created, just return it. 4414 if (llvm::GlobalValue *ResolverGV = GetGlobalValue(ResolverName)) 4415 return ResolverGV; 4416 4417 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4418 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI); 4419 4420 // The resolver needs to be created. For target and target_clones, defer 4421 // creation until the end of the TU. 4422 if (FD->isTargetMultiVersion() || FD->isTargetClonesMultiVersion()) 4423 AddDeferredMultiVersionResolverToEmit(GD); 4424 4425 // For cpu_specific, don't create an ifunc yet because we don't know if the 4426 // cpu_dispatch will be emitted in this translation unit. 4427 if (getTarget().supportsIFunc() && !FD->isCPUSpecificMultiVersion()) { 4428 llvm::Type *ResolverType = llvm::FunctionType::get( 4429 llvm::PointerType::get(DeclTy, 4430 getTypes().getTargetAddressSpace(FD->getType())), 4431 false); 4432 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 4433 MangledName + ".resolver", ResolverType, GlobalDecl{}, 4434 /*ForVTable=*/false); 4435 llvm::GlobalIFunc *GIF = 4436 llvm::GlobalIFunc::create(DeclTy, 0, getMultiversionLinkage(*this, GD), 4437 "", Resolver, &getModule()); 4438 GIF->setName(ResolverName); 4439 SetCommonAttributes(FD, GIF); 4440 4441 return GIF; 4442 } 4443 4444 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 4445 ResolverName, DeclTy, GlobalDecl{}, /*ForVTable=*/false); 4446 assert(isa<llvm::GlobalValue>(Resolver) && 4447 "Resolver should be created for the first time"); 4448 SetCommonAttributes(FD, cast<llvm::GlobalValue>(Resolver)); 4449 return Resolver; 4450 } 4451 4452 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the 4453 /// module, create and return an llvm Function with the specified type. If there 4454 /// is something in the module with the specified name, return it potentially 4455 /// bitcasted to the right type. 4456 /// 4457 /// If D is non-null, it specifies a decl that correspond to this. This is used 4458 /// to set the attributes on the function when it is first created. 4459 llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction( 4460 StringRef MangledName, llvm::Type *Ty, GlobalDecl GD, bool ForVTable, 4461 bool DontDefer, bool IsThunk, llvm::AttributeList ExtraAttrs, 4462 ForDefinition_t IsForDefinition) { 4463 const Decl *D = GD.getDecl(); 4464 4465 // Any attempts to use a MultiVersion function should result in retrieving 4466 // the iFunc instead. Name Mangling will handle the rest of the changes. 4467 if (const FunctionDecl *FD = cast_or_null<FunctionDecl>(D)) { 4468 // For the device mark the function as one that should be emitted. 4469 if (getLangOpts().OpenMPIsTargetDevice && OpenMPRuntime && 4470 !OpenMPRuntime->markAsGlobalTarget(GD) && FD->isDefined() && 4471 !DontDefer && !IsForDefinition) { 4472 if (const FunctionDecl *FDDef = FD->getDefinition()) { 4473 GlobalDecl GDDef; 4474 if (const auto *CD = dyn_cast<CXXConstructorDecl>(FDDef)) 4475 GDDef = GlobalDecl(CD, GD.getCtorType()); 4476 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(FDDef)) 4477 GDDef = GlobalDecl(DD, GD.getDtorType()); 4478 else 4479 GDDef = GlobalDecl(FDDef); 4480 EmitGlobal(GDDef); 4481 } 4482 } 4483 4484 if (FD->isMultiVersion()) { 4485 UpdateMultiVersionNames(GD, FD, MangledName); 4486 if (FD->getASTContext().getTargetInfo().getTriple().isAArch64() && 4487 !FD->isUsed()) 4488 AddDeferredMultiVersionResolverToEmit(GD); 4489 else if (!IsForDefinition) 4490 return GetOrCreateMultiVersionResolver(GD); 4491 } 4492 } 4493 4494 // Lookup the entry, lazily creating it if necessary. 4495 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 4496 if (Entry) { 4497 if (WeakRefReferences.erase(Entry)) { 4498 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D); 4499 if (FD && !FD->hasAttr<WeakAttr>()) 4500 Entry->setLinkage(llvm::Function::ExternalLinkage); 4501 } 4502 4503 // Handle dropped DLL attributes. 4504 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() && 4505 !shouldMapVisibilityToDLLExport(cast_or_null<NamedDecl>(D))) { 4506 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass); 4507 setDSOLocal(Entry); 4508 } 4509 4510 // If there are two attempts to define the same mangled name, issue an 4511 // error. 4512 if (IsForDefinition && !Entry->isDeclaration()) { 4513 GlobalDecl OtherGD; 4514 // Check that GD is not yet in DiagnosedConflictingDefinitions is required 4515 // to make sure that we issue an error only once. 4516 if (lookupRepresentativeDecl(MangledName, OtherGD) && 4517 (GD.getCanonicalDecl().getDecl() != 4518 OtherGD.getCanonicalDecl().getDecl()) && 4519 DiagnosedConflictingDefinitions.insert(GD).second) { 4520 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name) 4521 << MangledName; 4522 getDiags().Report(OtherGD.getDecl()->getLocation(), 4523 diag::note_previous_definition); 4524 } 4525 } 4526 4527 if ((isa<llvm::Function>(Entry) || isa<llvm::GlobalAlias>(Entry)) && 4528 (Entry->getValueType() == Ty)) { 4529 return Entry; 4530 } 4531 4532 // Make sure the result is of the correct type. 4533 // (If function is requested for a definition, we always need to create a new 4534 // function, not just return a bitcast.) 4535 if (!IsForDefinition) 4536 return Entry; 4537 } 4538 4539 // This function doesn't have a complete type (for example, the return 4540 // type is an incomplete struct). Use a fake type instead, and make 4541 // sure not to try to set attributes. 4542 bool IsIncompleteFunction = false; 4543 4544 llvm::FunctionType *FTy; 4545 if (isa<llvm::FunctionType>(Ty)) { 4546 FTy = cast<llvm::FunctionType>(Ty); 4547 } else { 4548 FTy = llvm::FunctionType::get(VoidTy, false); 4549 IsIncompleteFunction = true; 4550 } 4551 4552 llvm::Function *F = 4553 llvm::Function::Create(FTy, llvm::Function::ExternalLinkage, 4554 Entry ? StringRef() : MangledName, &getModule()); 4555 4556 // Store the declaration associated with this function so it is potentially 4557 // updated by further declarations or definitions and emitted at the end. 4558 if (D && D->hasAttr<AnnotateAttr>()) 4559 DeferredAnnotations[MangledName] = cast<ValueDecl>(D); 4560 4561 // If we already created a function with the same mangled name (but different 4562 // type) before, take its name and add it to the list of functions to be 4563 // replaced with F at the end of CodeGen. 4564 // 4565 // This happens if there is a prototype for a function (e.g. "int f()") and 4566 // then a definition of a different type (e.g. "int f(int x)"). 4567 if (Entry) { 4568 F->takeName(Entry); 4569 4570 // This might be an implementation of a function without a prototype, in 4571 // which case, try to do special replacement of calls which match the new 4572 // prototype. The really key thing here is that we also potentially drop 4573 // arguments from the call site so as to make a direct call, which makes the 4574 // inliner happier and suppresses a number of optimizer warnings (!) about 4575 // dropping arguments. 4576 if (!Entry->use_empty()) { 4577 ReplaceUsesOfNonProtoTypeWithRealFunction(Entry, F); 4578 Entry->removeDeadConstantUsers(); 4579 } 4580 4581 addGlobalValReplacement(Entry, F); 4582 } 4583 4584 assert(F->getName() == MangledName && "name was uniqued!"); 4585 if (D) 4586 SetFunctionAttributes(GD, F, IsIncompleteFunction, IsThunk); 4587 if (ExtraAttrs.hasFnAttrs()) { 4588 llvm::AttrBuilder B(F->getContext(), ExtraAttrs.getFnAttrs()); 4589 F->addFnAttrs(B); 4590 } 4591 4592 if (!DontDefer) { 4593 // All MSVC dtors other than the base dtor are linkonce_odr and delegate to 4594 // each other bottoming out with the base dtor. Therefore we emit non-base 4595 // dtors on usage, even if there is no dtor definition in the TU. 4596 if (isa_and_nonnull<CXXDestructorDecl>(D) && 4597 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D), 4598 GD.getDtorType())) 4599 addDeferredDeclToEmit(GD); 4600 4601 // This is the first use or definition of a mangled name. If there is a 4602 // deferred decl with this name, remember that we need to emit it at the end 4603 // of the file. 4604 auto DDI = DeferredDecls.find(MangledName); 4605 if (DDI != DeferredDecls.end()) { 4606 // Move the potentially referenced deferred decl to the 4607 // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we 4608 // don't need it anymore). 4609 addDeferredDeclToEmit(DDI->second); 4610 DeferredDecls.erase(DDI); 4611 4612 // Otherwise, there are cases we have to worry about where we're 4613 // using a declaration for which we must emit a definition but where 4614 // we might not find a top-level definition: 4615 // - member functions defined inline in their classes 4616 // - friend functions defined inline in some class 4617 // - special member functions with implicit definitions 4618 // If we ever change our AST traversal to walk into class methods, 4619 // this will be unnecessary. 4620 // 4621 // We also don't emit a definition for a function if it's going to be an 4622 // entry in a vtable, unless it's already marked as used. 4623 } else if (getLangOpts().CPlusPlus && D) { 4624 // Look for a declaration that's lexically in a record. 4625 for (const auto *FD = cast<FunctionDecl>(D)->getMostRecentDecl(); FD; 4626 FD = FD->getPreviousDecl()) { 4627 if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) { 4628 if (FD->doesThisDeclarationHaveABody()) { 4629 addDeferredDeclToEmit(GD.getWithDecl(FD)); 4630 break; 4631 } 4632 } 4633 } 4634 } 4635 } 4636 4637 // Make sure the result is of the requested type. 4638 if (!IsIncompleteFunction) { 4639 assert(F->getFunctionType() == Ty); 4640 return F; 4641 } 4642 4643 return F; 4644 } 4645 4646 /// GetAddrOfFunction - Return the address of the given function. If Ty is 4647 /// non-null, then this function will use the specified type if it has to 4648 /// create it (this occurs when we see a definition of the function). 4649 llvm::Constant * 4650 CodeGenModule::GetAddrOfFunction(GlobalDecl GD, llvm::Type *Ty, bool ForVTable, 4651 bool DontDefer, 4652 ForDefinition_t IsForDefinition) { 4653 // If there was no specific requested type, just convert it now. 4654 if (!Ty) { 4655 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4656 Ty = getTypes().ConvertType(FD->getType()); 4657 } 4658 4659 // Devirtualized destructor calls may come through here instead of via 4660 // getAddrOfCXXStructor. Make sure we use the MS ABI base destructor instead 4661 // of the complete destructor when necessary. 4662 if (const auto *DD = dyn_cast<CXXDestructorDecl>(GD.getDecl())) { 4663 if (getTarget().getCXXABI().isMicrosoft() && 4664 GD.getDtorType() == Dtor_Complete && 4665 DD->getParent()->getNumVBases() == 0) 4666 GD = GlobalDecl(DD, Dtor_Base); 4667 } 4668 4669 StringRef MangledName = getMangledName(GD); 4670 auto *F = GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable, DontDefer, 4671 /*IsThunk=*/false, llvm::AttributeList(), 4672 IsForDefinition); 4673 // Returns kernel handle for HIP kernel stub function. 4674 if (LangOpts.CUDA && !LangOpts.CUDAIsDevice && 4675 cast<FunctionDecl>(GD.getDecl())->hasAttr<CUDAGlobalAttr>()) { 4676 auto *Handle = getCUDARuntime().getKernelHandle( 4677 cast<llvm::Function>(F->stripPointerCasts()), GD); 4678 if (IsForDefinition) 4679 return F; 4680 return Handle; 4681 } 4682 return F; 4683 } 4684 4685 llvm::Constant *CodeGenModule::GetFunctionStart(const ValueDecl *Decl) { 4686 llvm::GlobalValue *F = 4687 cast<llvm::GlobalValue>(GetAddrOfFunction(Decl)->stripPointerCasts()); 4688 4689 return llvm::NoCFIValue::get(F); 4690 } 4691 4692 static const FunctionDecl * 4693 GetRuntimeFunctionDecl(ASTContext &C, StringRef Name) { 4694 TranslationUnitDecl *TUDecl = C.getTranslationUnitDecl(); 4695 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); 4696 4697 IdentifierInfo &CII = C.Idents.get(Name); 4698 for (const auto *Result : DC->lookup(&CII)) 4699 if (const auto *FD = dyn_cast<FunctionDecl>(Result)) 4700 return FD; 4701 4702 if (!C.getLangOpts().CPlusPlus) 4703 return nullptr; 4704 4705 // Demangle the premangled name from getTerminateFn() 4706 IdentifierInfo &CXXII = 4707 (Name == "_ZSt9terminatev" || Name == "?terminate@@YAXXZ") 4708 ? C.Idents.get("terminate") 4709 : C.Idents.get(Name); 4710 4711 for (const auto &N : {"__cxxabiv1", "std"}) { 4712 IdentifierInfo &NS = C.Idents.get(N); 4713 for (const auto *Result : DC->lookup(&NS)) { 4714 const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(Result); 4715 if (auto *LSD = dyn_cast<LinkageSpecDecl>(Result)) 4716 for (const auto *Result : LSD->lookup(&NS)) 4717 if ((ND = dyn_cast<NamespaceDecl>(Result))) 4718 break; 4719 4720 if (ND) 4721 for (const auto *Result : ND->lookup(&CXXII)) 4722 if (const auto *FD = dyn_cast<FunctionDecl>(Result)) 4723 return FD; 4724 } 4725 } 4726 4727 return nullptr; 4728 } 4729 4730 /// CreateRuntimeFunction - Create a new runtime function with the specified 4731 /// type and name. 4732 llvm::FunctionCallee 4733 CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy, StringRef Name, 4734 llvm::AttributeList ExtraAttrs, bool Local, 4735 bool AssumeConvergent) { 4736 if (AssumeConvergent) { 4737 ExtraAttrs = 4738 ExtraAttrs.addFnAttribute(VMContext, llvm::Attribute::Convergent); 4739 } 4740 4741 llvm::Constant *C = 4742 GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false, 4743 /*DontDefer=*/false, /*IsThunk=*/false, 4744 ExtraAttrs); 4745 4746 if (auto *F = dyn_cast<llvm::Function>(C)) { 4747 if (F->empty()) { 4748 F->setCallingConv(getRuntimeCC()); 4749 4750 // In Windows Itanium environments, try to mark runtime functions 4751 // dllimport. For Mingw and MSVC, don't. We don't really know if the user 4752 // will link their standard library statically or dynamically. Marking 4753 // functions imported when they are not imported can cause linker errors 4754 // and warnings. 4755 if (!Local && getTriple().isWindowsItaniumEnvironment() && 4756 !getCodeGenOpts().LTOVisibilityPublicStd) { 4757 const FunctionDecl *FD = GetRuntimeFunctionDecl(Context, Name); 4758 if (!FD || FD->hasAttr<DLLImportAttr>()) { 4759 F->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass); 4760 F->setLinkage(llvm::GlobalValue::ExternalLinkage); 4761 } 4762 } 4763 setDSOLocal(F); 4764 } 4765 } 4766 4767 return {FTy, C}; 4768 } 4769 4770 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module, 4771 /// create and return an llvm GlobalVariable with the specified type and address 4772 /// space. If there is something in the module with the specified name, return 4773 /// it potentially bitcasted to the right type. 4774 /// 4775 /// If D is non-null, it specifies a decl that correspond to this. This is used 4776 /// to set the attributes on the global when it is first created. 4777 /// 4778 /// If IsForDefinition is true, it is guaranteed that an actual global with 4779 /// type Ty will be returned, not conversion of a variable with the same 4780 /// mangled name but some other type. 4781 llvm::Constant * 4782 CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty, 4783 LangAS AddrSpace, const VarDecl *D, 4784 ForDefinition_t IsForDefinition) { 4785 // Lookup the entry, lazily creating it if necessary. 4786 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 4787 unsigned TargetAS = getContext().getTargetAddressSpace(AddrSpace); 4788 if (Entry) { 4789 if (WeakRefReferences.erase(Entry)) { 4790 if (D && !D->hasAttr<WeakAttr>()) 4791 Entry->setLinkage(llvm::Function::ExternalLinkage); 4792 } 4793 4794 // Handle dropped DLL attributes. 4795 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() && 4796 !shouldMapVisibilityToDLLExport(D)) 4797 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass); 4798 4799 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd && D) 4800 getOpenMPRuntime().registerTargetGlobalVariable(D, Entry); 4801 4802 if (Entry->getValueType() == Ty && Entry->getAddressSpace() == TargetAS) 4803 return Entry; 4804 4805 // If there are two attempts to define the same mangled name, issue an 4806 // error. 4807 if (IsForDefinition && !Entry->isDeclaration()) { 4808 GlobalDecl OtherGD; 4809 const VarDecl *OtherD; 4810 4811 // Check that D is not yet in DiagnosedConflictingDefinitions is required 4812 // to make sure that we issue an error only once. 4813 if (D && lookupRepresentativeDecl(MangledName, OtherGD) && 4814 (D->getCanonicalDecl() != OtherGD.getCanonicalDecl().getDecl()) && 4815 (OtherD = dyn_cast<VarDecl>(OtherGD.getDecl())) && 4816 OtherD->hasInit() && 4817 DiagnosedConflictingDefinitions.insert(D).second) { 4818 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name) 4819 << MangledName; 4820 getDiags().Report(OtherGD.getDecl()->getLocation(), 4821 diag::note_previous_definition); 4822 } 4823 } 4824 4825 // Make sure the result is of the correct type. 4826 if (Entry->getType()->getAddressSpace() != TargetAS) 4827 return llvm::ConstantExpr::getAddrSpaceCast( 4828 Entry, llvm::PointerType::get(Ty->getContext(), TargetAS)); 4829 4830 // (If global is requested for a definition, we always need to create a new 4831 // global, not just return a bitcast.) 4832 if (!IsForDefinition) 4833 return Entry; 4834 } 4835 4836 auto DAddrSpace = GetGlobalVarAddressSpace(D); 4837 4838 auto *GV = new llvm::GlobalVariable( 4839 getModule(), Ty, false, llvm::GlobalValue::ExternalLinkage, nullptr, 4840 MangledName, nullptr, llvm::GlobalVariable::NotThreadLocal, 4841 getContext().getTargetAddressSpace(DAddrSpace)); 4842 4843 // If we already created a global with the same mangled name (but different 4844 // type) before, take its name and remove it from its parent. 4845 if (Entry) { 4846 GV->takeName(Entry); 4847 4848 if (!Entry->use_empty()) { 4849 Entry->replaceAllUsesWith(GV); 4850 } 4851 4852 Entry->eraseFromParent(); 4853 } 4854 4855 // This is the first use or definition of a mangled name. If there is a 4856 // deferred decl with this name, remember that we need to emit it at the end 4857 // of the file. 4858 auto DDI = DeferredDecls.find(MangledName); 4859 if (DDI != DeferredDecls.end()) { 4860 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 4861 // list, and remove it from DeferredDecls (since we don't need it anymore). 4862 addDeferredDeclToEmit(DDI->second); 4863 DeferredDecls.erase(DDI); 4864 } 4865 4866 // Handle things which are present even on external declarations. 4867 if (D) { 4868 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd) 4869 getOpenMPRuntime().registerTargetGlobalVariable(D, GV); 4870 4871 // FIXME: This code is overly simple and should be merged with other global 4872 // handling. 4873 GV->setConstant(D->getType().isConstantStorage(getContext(), false, false)); 4874 4875 GV->setAlignment(getContext().getDeclAlign(D).getAsAlign()); 4876 4877 setLinkageForGV(GV, D); 4878 4879 if (D->getTLSKind()) { 4880 if (D->getTLSKind() == VarDecl::TLS_Dynamic) 4881 CXXThreadLocals.push_back(D); 4882 setTLSMode(GV, *D); 4883 } 4884 4885 setGVProperties(GV, D); 4886 4887 // If required by the ABI, treat declarations of static data members with 4888 // inline initializers as definitions. 4889 if (getContext().isMSStaticDataMemberInlineDefinition(D)) { 4890 EmitGlobalVarDefinition(D); 4891 } 4892 4893 // Emit section information for extern variables. 4894 if (D->hasExternalStorage()) { 4895 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) 4896 GV->setSection(SA->getName()); 4897 } 4898 4899 // Handle XCore specific ABI requirements. 4900 if (getTriple().getArch() == llvm::Triple::xcore && 4901 D->getLanguageLinkage() == CLanguageLinkage && 4902 D->getType().isConstant(Context) && 4903 isExternallyVisible(D->getLinkageAndVisibility().getLinkage())) 4904 GV->setSection(".cp.rodata"); 4905 4906 // Handle code model attribute 4907 if (const auto *CMA = D->getAttr<CodeModelAttr>()) 4908 GV->setCodeModel(CMA->getModel()); 4909 4910 // Check if we a have a const declaration with an initializer, we may be 4911 // able to emit it as available_externally to expose it's value to the 4912 // optimizer. 4913 if (Context.getLangOpts().CPlusPlus && GV->hasExternalLinkage() && 4914 D->getType().isConstQualified() && !GV->hasInitializer() && 4915 !D->hasDefinition() && D->hasInit() && !D->hasAttr<DLLImportAttr>()) { 4916 const auto *Record = 4917 Context.getBaseElementType(D->getType())->getAsCXXRecordDecl(); 4918 bool HasMutableFields = Record && Record->hasMutableFields(); 4919 if (!HasMutableFields) { 4920 const VarDecl *InitDecl; 4921 const Expr *InitExpr = D->getAnyInitializer(InitDecl); 4922 if (InitExpr) { 4923 ConstantEmitter emitter(*this); 4924 llvm::Constant *Init = emitter.tryEmitForInitializer(*InitDecl); 4925 if (Init) { 4926 auto *InitType = Init->getType(); 4927 if (GV->getValueType() != InitType) { 4928 // The type of the initializer does not match the definition. 4929 // This happens when an initializer has a different type from 4930 // the type of the global (because of padding at the end of a 4931 // structure for instance). 4932 GV->setName(StringRef()); 4933 // Make a new global with the correct type, this is now guaranteed 4934 // to work. 4935 auto *NewGV = cast<llvm::GlobalVariable>( 4936 GetAddrOfGlobalVar(D, InitType, IsForDefinition) 4937 ->stripPointerCasts()); 4938 4939 // Erase the old global, since it is no longer used. 4940 GV->eraseFromParent(); 4941 GV = NewGV; 4942 } else { 4943 GV->setInitializer(Init); 4944 GV->setConstant(true); 4945 GV->setLinkage(llvm::GlobalValue::AvailableExternallyLinkage); 4946 } 4947 emitter.finalize(GV); 4948 } 4949 } 4950 } 4951 } 4952 } 4953 4954 if (D && 4955 D->isThisDeclarationADefinition(Context) == VarDecl::DeclarationOnly) { 4956 getTargetCodeGenInfo().setTargetAttributes(D, GV, *this); 4957 // External HIP managed variables needed to be recorded for transformation 4958 // in both device and host compilations. 4959 if (getLangOpts().CUDA && D && D->hasAttr<HIPManagedAttr>() && 4960 D->hasExternalStorage()) 4961 getCUDARuntime().handleVarRegistration(D, *GV); 4962 } 4963 4964 if (D) 4965 SanitizerMD->reportGlobal(GV, *D); 4966 4967 LangAS ExpectedAS = 4968 D ? D->getType().getAddressSpace() 4969 : (LangOpts.OpenCL ? LangAS::opencl_global : LangAS::Default); 4970 assert(getContext().getTargetAddressSpace(ExpectedAS) == TargetAS); 4971 if (DAddrSpace != ExpectedAS) { 4972 return getTargetCodeGenInfo().performAddrSpaceCast( 4973 *this, GV, DAddrSpace, ExpectedAS, 4974 llvm::PointerType::get(getLLVMContext(), TargetAS)); 4975 } 4976 4977 return GV; 4978 } 4979 4980 llvm::Constant * 4981 CodeGenModule::GetAddrOfGlobal(GlobalDecl GD, ForDefinition_t IsForDefinition) { 4982 const Decl *D = GD.getDecl(); 4983 4984 if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D)) 4985 return getAddrOfCXXStructor(GD, /*FnInfo=*/nullptr, /*FnType=*/nullptr, 4986 /*DontDefer=*/false, IsForDefinition); 4987 4988 if (isa<CXXMethodDecl>(D)) { 4989 auto FInfo = 4990 &getTypes().arrangeCXXMethodDeclaration(cast<CXXMethodDecl>(D)); 4991 auto Ty = getTypes().GetFunctionType(*FInfo); 4992 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false, 4993 IsForDefinition); 4994 } 4995 4996 if (isa<FunctionDecl>(D)) { 4997 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4998 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 4999 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false, 5000 IsForDefinition); 5001 } 5002 5003 return GetAddrOfGlobalVar(cast<VarDecl>(D), /*Ty=*/nullptr, IsForDefinition); 5004 } 5005 5006 llvm::GlobalVariable *CodeGenModule::CreateOrReplaceCXXRuntimeVariable( 5007 StringRef Name, llvm::Type *Ty, llvm::GlobalValue::LinkageTypes Linkage, 5008 llvm::Align Alignment) { 5009 llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name); 5010 llvm::GlobalVariable *OldGV = nullptr; 5011 5012 if (GV) { 5013 // Check if the variable has the right type. 5014 if (GV->getValueType() == Ty) 5015 return GV; 5016 5017 // Because C++ name mangling, the only way we can end up with an already 5018 // existing global with the same name is if it has been declared extern "C". 5019 assert(GV->isDeclaration() && "Declaration has wrong type!"); 5020 OldGV = GV; 5021 } 5022 5023 // Create a new variable. 5024 GV = new llvm::GlobalVariable(getModule(), Ty, /*isConstant=*/true, 5025 Linkage, nullptr, Name); 5026 5027 if (OldGV) { 5028 // Replace occurrences of the old variable if needed. 5029 GV->takeName(OldGV); 5030 5031 if (!OldGV->use_empty()) { 5032 OldGV->replaceAllUsesWith(GV); 5033 } 5034 5035 OldGV->eraseFromParent(); 5036 } 5037 5038 if (supportsCOMDAT() && GV->isWeakForLinker() && 5039 !GV->hasAvailableExternallyLinkage()) 5040 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 5041 5042 GV->setAlignment(Alignment); 5043 5044 return GV; 5045 } 5046 5047 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the 5048 /// given global variable. If Ty is non-null and if the global doesn't exist, 5049 /// then it will be created with the specified type instead of whatever the 5050 /// normal requested type would be. If IsForDefinition is true, it is guaranteed 5051 /// that an actual global with type Ty will be returned, not conversion of a 5052 /// variable with the same mangled name but some other type. 5053 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D, 5054 llvm::Type *Ty, 5055 ForDefinition_t IsForDefinition) { 5056 assert(D->hasGlobalStorage() && "Not a global variable"); 5057 QualType ASTTy = D->getType(); 5058 if (!Ty) 5059 Ty = getTypes().ConvertTypeForMem(ASTTy); 5060 5061 StringRef MangledName = getMangledName(D); 5062 return GetOrCreateLLVMGlobal(MangledName, Ty, ASTTy.getAddressSpace(), D, 5063 IsForDefinition); 5064 } 5065 5066 /// CreateRuntimeVariable - Create a new runtime global variable with the 5067 /// specified type and name. 5068 llvm::Constant * 5069 CodeGenModule::CreateRuntimeVariable(llvm::Type *Ty, 5070 StringRef Name) { 5071 LangAS AddrSpace = getContext().getLangOpts().OpenCL ? LangAS::opencl_global 5072 : LangAS::Default; 5073 auto *Ret = GetOrCreateLLVMGlobal(Name, Ty, AddrSpace, nullptr); 5074 setDSOLocal(cast<llvm::GlobalValue>(Ret->stripPointerCasts())); 5075 return Ret; 5076 } 5077 5078 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) { 5079 assert(!D->getInit() && "Cannot emit definite definitions here!"); 5080 5081 StringRef MangledName = getMangledName(D); 5082 llvm::GlobalValue *GV = GetGlobalValue(MangledName); 5083 5084 // We already have a definition, not declaration, with the same mangled name. 5085 // Emitting of declaration is not required (and actually overwrites emitted 5086 // definition). 5087 if (GV && !GV->isDeclaration()) 5088 return; 5089 5090 // If we have not seen a reference to this variable yet, place it into the 5091 // deferred declarations table to be emitted if needed later. 5092 if (!MustBeEmitted(D) && !GV) { 5093 DeferredDecls[MangledName] = D; 5094 return; 5095 } 5096 5097 // The tentative definition is the only definition. 5098 EmitGlobalVarDefinition(D); 5099 } 5100 5101 void CodeGenModule::EmitExternalDeclaration(const VarDecl *D) { 5102 EmitExternalVarDeclaration(D); 5103 } 5104 5105 CharUnits CodeGenModule::GetTargetTypeStoreSize(llvm::Type *Ty) const { 5106 return Context.toCharUnitsFromBits( 5107 getDataLayout().getTypeStoreSizeInBits(Ty)); 5108 } 5109 5110 LangAS CodeGenModule::GetGlobalVarAddressSpace(const VarDecl *D) { 5111 if (LangOpts.OpenCL) { 5112 LangAS AS = D ? D->getType().getAddressSpace() : LangAS::opencl_global; 5113 assert(AS == LangAS::opencl_global || 5114 AS == LangAS::opencl_global_device || 5115 AS == LangAS::opencl_global_host || 5116 AS == LangAS::opencl_constant || 5117 AS == LangAS::opencl_local || 5118 AS >= LangAS::FirstTargetAddressSpace); 5119 return AS; 5120 } 5121 5122 if (LangOpts.SYCLIsDevice && 5123 (!D || D->getType().getAddressSpace() == LangAS::Default)) 5124 return LangAS::sycl_global; 5125 5126 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) { 5127 if (D) { 5128 if (D->hasAttr<CUDAConstantAttr>()) 5129 return LangAS::cuda_constant; 5130 if (D->hasAttr<CUDASharedAttr>()) 5131 return LangAS::cuda_shared; 5132 if (D->hasAttr<CUDADeviceAttr>()) 5133 return LangAS::cuda_device; 5134 if (D->getType().isConstQualified()) 5135 return LangAS::cuda_constant; 5136 } 5137 return LangAS::cuda_device; 5138 } 5139 5140 if (LangOpts.OpenMP) { 5141 LangAS AS; 5142 if (OpenMPRuntime->hasAllocateAttributeForGlobalVar(D, AS)) 5143 return AS; 5144 } 5145 return getTargetCodeGenInfo().getGlobalVarAddressSpace(*this, D); 5146 } 5147 5148 LangAS CodeGenModule::GetGlobalConstantAddressSpace() const { 5149 // OpenCL v1.2 s6.5.3: a string literal is in the constant address space. 5150 if (LangOpts.OpenCL) 5151 return LangAS::opencl_constant; 5152 if (LangOpts.SYCLIsDevice) 5153 return LangAS::sycl_global; 5154 if (LangOpts.HIP && LangOpts.CUDAIsDevice && getTriple().isSPIRV()) 5155 // For HIPSPV map literals to cuda_device (maps to CrossWorkGroup in SPIR-V) 5156 // instead of default AS (maps to Generic in SPIR-V). Otherwise, we end up 5157 // with OpVariable instructions with Generic storage class which is not 5158 // allowed (SPIR-V V1.6 s3.42.8). Also, mapping literals to SPIR-V 5159 // UniformConstant storage class is not viable as pointers to it may not be 5160 // casted to Generic pointers which are used to model HIP's "flat" pointers. 5161 return LangAS::cuda_device; 5162 if (auto AS = getTarget().getConstantAddressSpace()) 5163 return *AS; 5164 return LangAS::Default; 5165 } 5166 5167 // In address space agnostic languages, string literals are in default address 5168 // space in AST. However, certain targets (e.g. amdgcn) request them to be 5169 // emitted in constant address space in LLVM IR. To be consistent with other 5170 // parts of AST, string literal global variables in constant address space 5171 // need to be casted to default address space before being put into address 5172 // map and referenced by other part of CodeGen. 5173 // In OpenCL, string literals are in constant address space in AST, therefore 5174 // they should not be casted to default address space. 5175 static llvm::Constant * 5176 castStringLiteralToDefaultAddressSpace(CodeGenModule &CGM, 5177 llvm::GlobalVariable *GV) { 5178 llvm::Constant *Cast = GV; 5179 if (!CGM.getLangOpts().OpenCL) { 5180 auto AS = CGM.GetGlobalConstantAddressSpace(); 5181 if (AS != LangAS::Default) 5182 Cast = CGM.getTargetCodeGenInfo().performAddrSpaceCast( 5183 CGM, GV, AS, LangAS::Default, 5184 llvm::PointerType::get( 5185 CGM.getLLVMContext(), 5186 CGM.getContext().getTargetAddressSpace(LangAS::Default))); 5187 } 5188 return Cast; 5189 } 5190 5191 template<typename SomeDecl> 5192 void CodeGenModule::MaybeHandleStaticInExternC(const SomeDecl *D, 5193 llvm::GlobalValue *GV) { 5194 if (!getLangOpts().CPlusPlus) 5195 return; 5196 5197 // Must have 'used' attribute, or else inline assembly can't rely on 5198 // the name existing. 5199 if (!D->template hasAttr<UsedAttr>()) 5200 return; 5201 5202 // Must have internal linkage and an ordinary name. 5203 if (!D->getIdentifier() || D->getFormalLinkage() != Linkage::Internal) 5204 return; 5205 5206 // Must be in an extern "C" context. Entities declared directly within 5207 // a record are not extern "C" even if the record is in such a context. 5208 const SomeDecl *First = D->getFirstDecl(); 5209 if (First->getDeclContext()->isRecord() || !First->isInExternCContext()) 5210 return; 5211 5212 // OK, this is an internal linkage entity inside an extern "C" linkage 5213 // specification. Make a note of that so we can give it the "expected" 5214 // mangled name if nothing else is using that name. 5215 std::pair<StaticExternCMap::iterator, bool> R = 5216 StaticExternCValues.insert(std::make_pair(D->getIdentifier(), GV)); 5217 5218 // If we have multiple internal linkage entities with the same name 5219 // in extern "C" regions, none of them gets that name. 5220 if (!R.second) 5221 R.first->second = nullptr; 5222 } 5223 5224 static bool shouldBeInCOMDAT(CodeGenModule &CGM, const Decl &D) { 5225 if (!CGM.supportsCOMDAT()) 5226 return false; 5227 5228 if (D.hasAttr<SelectAnyAttr>()) 5229 return true; 5230 5231 GVALinkage Linkage; 5232 if (auto *VD = dyn_cast<VarDecl>(&D)) 5233 Linkage = CGM.getContext().GetGVALinkageForVariable(VD); 5234 else 5235 Linkage = CGM.getContext().GetGVALinkageForFunction(cast<FunctionDecl>(&D)); 5236 5237 switch (Linkage) { 5238 case GVA_Internal: 5239 case GVA_AvailableExternally: 5240 case GVA_StrongExternal: 5241 return false; 5242 case GVA_DiscardableODR: 5243 case GVA_StrongODR: 5244 return true; 5245 } 5246 llvm_unreachable("No such linkage"); 5247 } 5248 5249 bool CodeGenModule::supportsCOMDAT() const { 5250 return getTriple().supportsCOMDAT(); 5251 } 5252 5253 void CodeGenModule::maybeSetTrivialComdat(const Decl &D, 5254 llvm::GlobalObject &GO) { 5255 if (!shouldBeInCOMDAT(*this, D)) 5256 return; 5257 GO.setComdat(TheModule.getOrInsertComdat(GO.getName())); 5258 } 5259 5260 /// Pass IsTentative as true if you want to create a tentative definition. 5261 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D, 5262 bool IsTentative) { 5263 // OpenCL global variables of sampler type are translated to function calls, 5264 // therefore no need to be translated. 5265 QualType ASTTy = D->getType(); 5266 if (getLangOpts().OpenCL && ASTTy->isSamplerT()) 5267 return; 5268 5269 // If this is OpenMP device, check if it is legal to emit this global 5270 // normally. 5271 if (LangOpts.OpenMPIsTargetDevice && OpenMPRuntime && 5272 OpenMPRuntime->emitTargetGlobalVariable(D)) 5273 return; 5274 5275 llvm::TrackingVH<llvm::Constant> Init; 5276 bool NeedsGlobalCtor = false; 5277 // Whether the definition of the variable is available externally. 5278 // If yes, we shouldn't emit the GloablCtor and GlobalDtor for the variable 5279 // since this is the job for its original source. 5280 bool IsDefinitionAvailableExternally = 5281 getContext().GetGVALinkageForVariable(D) == GVA_AvailableExternally; 5282 bool NeedsGlobalDtor = 5283 !IsDefinitionAvailableExternally && 5284 D->needsDestruction(getContext()) == QualType::DK_cxx_destructor; 5285 5286 const VarDecl *InitDecl; 5287 const Expr *InitExpr = D->getAnyInitializer(InitDecl); 5288 5289 std::optional<ConstantEmitter> emitter; 5290 5291 // CUDA E.2.4.1 "__shared__ variables cannot have an initialization 5292 // as part of their declaration." Sema has already checked for 5293 // error cases, so we just need to set Init to UndefValue. 5294 bool IsCUDASharedVar = 5295 getLangOpts().CUDAIsDevice && D->hasAttr<CUDASharedAttr>(); 5296 // Shadows of initialized device-side global variables are also left 5297 // undefined. 5298 // Managed Variables should be initialized on both host side and device side. 5299 bool IsCUDAShadowVar = 5300 !getLangOpts().CUDAIsDevice && !D->hasAttr<HIPManagedAttr>() && 5301 (D->hasAttr<CUDAConstantAttr>() || D->hasAttr<CUDADeviceAttr>() || 5302 D->hasAttr<CUDASharedAttr>()); 5303 bool IsCUDADeviceShadowVar = 5304 getLangOpts().CUDAIsDevice && !D->hasAttr<HIPManagedAttr>() && 5305 (D->getType()->isCUDADeviceBuiltinSurfaceType() || 5306 D->getType()->isCUDADeviceBuiltinTextureType()); 5307 if (getLangOpts().CUDA && 5308 (IsCUDASharedVar || IsCUDAShadowVar || IsCUDADeviceShadowVar)) 5309 Init = llvm::UndefValue::get(getTypes().ConvertTypeForMem(ASTTy)); 5310 else if (D->hasAttr<LoaderUninitializedAttr>()) 5311 Init = llvm::UndefValue::get(getTypes().ConvertTypeForMem(ASTTy)); 5312 else if (!InitExpr) { 5313 // This is a tentative definition; tentative definitions are 5314 // implicitly initialized with { 0 }. 5315 // 5316 // Note that tentative definitions are only emitted at the end of 5317 // a translation unit, so they should never have incomplete 5318 // type. In addition, EmitTentativeDefinition makes sure that we 5319 // never attempt to emit a tentative definition if a real one 5320 // exists. A use may still exists, however, so we still may need 5321 // to do a RAUW. 5322 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type"); 5323 Init = EmitNullConstant(D->getType()); 5324 } else { 5325 initializedGlobalDecl = GlobalDecl(D); 5326 emitter.emplace(*this); 5327 llvm::Constant *Initializer = emitter->tryEmitForInitializer(*InitDecl); 5328 if (!Initializer) { 5329 QualType T = InitExpr->getType(); 5330 if (D->getType()->isReferenceType()) 5331 T = D->getType(); 5332 5333 if (getLangOpts().CPlusPlus) { 5334 if (InitDecl->hasFlexibleArrayInit(getContext())) 5335 ErrorUnsupported(D, "flexible array initializer"); 5336 Init = EmitNullConstant(T); 5337 5338 if (!IsDefinitionAvailableExternally) 5339 NeedsGlobalCtor = true; 5340 } else { 5341 ErrorUnsupported(D, "static initializer"); 5342 Init = llvm::UndefValue::get(getTypes().ConvertType(T)); 5343 } 5344 } else { 5345 Init = Initializer; 5346 // We don't need an initializer, so remove the entry for the delayed 5347 // initializer position (just in case this entry was delayed) if we 5348 // also don't need to register a destructor. 5349 if (getLangOpts().CPlusPlus && !NeedsGlobalDtor) 5350 DelayedCXXInitPosition.erase(D); 5351 5352 #ifndef NDEBUG 5353 CharUnits VarSize = getContext().getTypeSizeInChars(ASTTy) + 5354 InitDecl->getFlexibleArrayInitChars(getContext()); 5355 CharUnits CstSize = CharUnits::fromQuantity( 5356 getDataLayout().getTypeAllocSize(Init->getType())); 5357 assert(VarSize == CstSize && "Emitted constant has unexpected size"); 5358 #endif 5359 } 5360 } 5361 5362 llvm::Type* InitType = Init->getType(); 5363 llvm::Constant *Entry = 5364 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)); 5365 5366 // Strip off pointer casts if we got them. 5367 Entry = Entry->stripPointerCasts(); 5368 5369 // Entry is now either a Function or GlobalVariable. 5370 auto *GV = dyn_cast<llvm::GlobalVariable>(Entry); 5371 5372 // We have a definition after a declaration with the wrong type. 5373 // We must make a new GlobalVariable* and update everything that used OldGV 5374 // (a declaration or tentative definition) with the new GlobalVariable* 5375 // (which will be a definition). 5376 // 5377 // This happens if there is a prototype for a global (e.g. 5378 // "extern int x[];") and then a definition of a different type (e.g. 5379 // "int x[10];"). This also happens when an initializer has a different type 5380 // from the type of the global (this happens with unions). 5381 if (!GV || GV->getValueType() != InitType || 5382 GV->getType()->getAddressSpace() != 5383 getContext().getTargetAddressSpace(GetGlobalVarAddressSpace(D))) { 5384 5385 // Move the old entry aside so that we'll create a new one. 5386 Entry->setName(StringRef()); 5387 5388 // Make a new global with the correct type, this is now guaranteed to work. 5389 GV = cast<llvm::GlobalVariable>( 5390 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)) 5391 ->stripPointerCasts()); 5392 5393 // Replace all uses of the old global with the new global 5394 llvm::Constant *NewPtrForOldDecl = 5395 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, 5396 Entry->getType()); 5397 Entry->replaceAllUsesWith(NewPtrForOldDecl); 5398 5399 // Erase the old global, since it is no longer used. 5400 cast<llvm::GlobalValue>(Entry)->eraseFromParent(); 5401 } 5402 5403 MaybeHandleStaticInExternC(D, GV); 5404 5405 if (D->hasAttr<AnnotateAttr>()) 5406 AddGlobalAnnotations(D, GV); 5407 5408 // Set the llvm linkage type as appropriate. 5409 llvm::GlobalValue::LinkageTypes Linkage = getLLVMLinkageVarDefinition(D); 5410 5411 // CUDA B.2.1 "The __device__ qualifier declares a variable that resides on 5412 // the device. [...]" 5413 // CUDA B.2.2 "The __constant__ qualifier, optionally used together with 5414 // __device__, declares a variable that: [...] 5415 // Is accessible from all the threads within the grid and from the host 5416 // through the runtime library (cudaGetSymbolAddress() / cudaGetSymbolSize() 5417 // / cudaMemcpyToSymbol() / cudaMemcpyFromSymbol())." 5418 if (LangOpts.CUDA) { 5419 if (LangOpts.CUDAIsDevice) { 5420 if (Linkage != llvm::GlobalValue::InternalLinkage && 5421 (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>() || 5422 D->getType()->isCUDADeviceBuiltinSurfaceType() || 5423 D->getType()->isCUDADeviceBuiltinTextureType())) 5424 GV->setExternallyInitialized(true); 5425 } else { 5426 getCUDARuntime().internalizeDeviceSideVar(D, Linkage); 5427 } 5428 getCUDARuntime().handleVarRegistration(D, *GV); 5429 } 5430 5431 GV->setInitializer(Init); 5432 if (emitter) 5433 emitter->finalize(GV); 5434 5435 // If it is safe to mark the global 'constant', do so now. 5436 GV->setConstant(!NeedsGlobalCtor && !NeedsGlobalDtor && 5437 D->getType().isConstantStorage(getContext(), true, true)); 5438 5439 // If it is in a read-only section, mark it 'constant'. 5440 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) { 5441 const ASTContext::SectionInfo &SI = Context.SectionInfos[SA->getName()]; 5442 if ((SI.SectionFlags & ASTContext::PSF_Write) == 0) 5443 GV->setConstant(true); 5444 } 5445 5446 CharUnits AlignVal = getContext().getDeclAlign(D); 5447 // Check for alignment specifed in an 'omp allocate' directive. 5448 if (std::optional<CharUnits> AlignValFromAllocate = 5449 getOMPAllocateAlignment(D)) 5450 AlignVal = *AlignValFromAllocate; 5451 GV->setAlignment(AlignVal.getAsAlign()); 5452 5453 // On Darwin, unlike other Itanium C++ ABI platforms, the thread-wrapper 5454 // function is only defined alongside the variable, not also alongside 5455 // callers. Normally, all accesses to a thread_local go through the 5456 // thread-wrapper in order to ensure initialization has occurred, underlying 5457 // variable will never be used other than the thread-wrapper, so it can be 5458 // converted to internal linkage. 5459 // 5460 // However, if the variable has the 'constinit' attribute, it _can_ be 5461 // referenced directly, without calling the thread-wrapper, so the linkage 5462 // must not be changed. 5463 // 5464 // Additionally, if the variable isn't plain external linkage, e.g. if it's 5465 // weak or linkonce, the de-duplication semantics are important to preserve, 5466 // so we don't change the linkage. 5467 if (D->getTLSKind() == VarDecl::TLS_Dynamic && 5468 Linkage == llvm::GlobalValue::ExternalLinkage && 5469 Context.getTargetInfo().getTriple().isOSDarwin() && 5470 !D->hasAttr<ConstInitAttr>()) 5471 Linkage = llvm::GlobalValue::InternalLinkage; 5472 5473 GV->setLinkage(Linkage); 5474 if (D->hasAttr<DLLImportAttr>()) 5475 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass); 5476 else if (D->hasAttr<DLLExportAttr>()) 5477 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass); 5478 else 5479 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass); 5480 5481 if (Linkage == llvm::GlobalVariable::CommonLinkage) { 5482 // common vars aren't constant even if declared const. 5483 GV->setConstant(false); 5484 // Tentative definition of global variables may be initialized with 5485 // non-zero null pointers. In this case they should have weak linkage 5486 // since common linkage must have zero initializer and must not have 5487 // explicit section therefore cannot have non-zero initial value. 5488 if (!GV->getInitializer()->isNullValue()) 5489 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 5490 } 5491 5492 setNonAliasAttributes(D, GV); 5493 5494 if (D->getTLSKind() && !GV->isThreadLocal()) { 5495 if (D->getTLSKind() == VarDecl::TLS_Dynamic) 5496 CXXThreadLocals.push_back(D); 5497 setTLSMode(GV, *D); 5498 } 5499 5500 maybeSetTrivialComdat(*D, *GV); 5501 5502 // Emit the initializer function if necessary. 5503 if (NeedsGlobalCtor || NeedsGlobalDtor) 5504 EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor); 5505 5506 SanitizerMD->reportGlobal(GV, *D, NeedsGlobalCtor); 5507 5508 // Emit global variable debug information. 5509 if (CGDebugInfo *DI = getModuleDebugInfo()) 5510 if (getCodeGenOpts().hasReducedDebugInfo()) 5511 DI->EmitGlobalVariable(GV, D); 5512 } 5513 5514 void CodeGenModule::EmitExternalVarDeclaration(const VarDecl *D) { 5515 if (CGDebugInfo *DI = getModuleDebugInfo()) 5516 if (getCodeGenOpts().hasReducedDebugInfo()) { 5517 QualType ASTTy = D->getType(); 5518 llvm::Type *Ty = getTypes().ConvertTypeForMem(D->getType()); 5519 llvm::Constant *GV = 5520 GetOrCreateLLVMGlobal(D->getName(), Ty, ASTTy.getAddressSpace(), D); 5521 DI->EmitExternalVariable( 5522 cast<llvm::GlobalVariable>(GV->stripPointerCasts()), D); 5523 } 5524 } 5525 5526 static bool isVarDeclStrongDefinition(const ASTContext &Context, 5527 CodeGenModule &CGM, const VarDecl *D, 5528 bool NoCommon) { 5529 // Don't give variables common linkage if -fno-common was specified unless it 5530 // was overridden by a NoCommon attribute. 5531 if ((NoCommon || D->hasAttr<NoCommonAttr>()) && !D->hasAttr<CommonAttr>()) 5532 return true; 5533 5534 // C11 6.9.2/2: 5535 // A declaration of an identifier for an object that has file scope without 5536 // an initializer, and without a storage-class specifier or with the 5537 // storage-class specifier static, constitutes a tentative definition. 5538 if (D->getInit() || D->hasExternalStorage()) 5539 return true; 5540 5541 // A variable cannot be both common and exist in a section. 5542 if (D->hasAttr<SectionAttr>()) 5543 return true; 5544 5545 // A variable cannot be both common and exist in a section. 5546 // We don't try to determine which is the right section in the front-end. 5547 // If no specialized section name is applicable, it will resort to default. 5548 if (D->hasAttr<PragmaClangBSSSectionAttr>() || 5549 D->hasAttr<PragmaClangDataSectionAttr>() || 5550 D->hasAttr<PragmaClangRelroSectionAttr>() || 5551 D->hasAttr<PragmaClangRodataSectionAttr>()) 5552 return true; 5553 5554 // Thread local vars aren't considered common linkage. 5555 if (D->getTLSKind()) 5556 return true; 5557 5558 // Tentative definitions marked with WeakImportAttr are true definitions. 5559 if (D->hasAttr<WeakImportAttr>()) 5560 return true; 5561 5562 // A variable cannot be both common and exist in a comdat. 5563 if (shouldBeInCOMDAT(CGM, *D)) 5564 return true; 5565 5566 // Declarations with a required alignment do not have common linkage in MSVC 5567 // mode. 5568 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) { 5569 if (D->hasAttr<AlignedAttr>()) 5570 return true; 5571 QualType VarType = D->getType(); 5572 if (Context.isAlignmentRequired(VarType)) 5573 return true; 5574 5575 if (const auto *RT = VarType->getAs<RecordType>()) { 5576 const RecordDecl *RD = RT->getDecl(); 5577 for (const FieldDecl *FD : RD->fields()) { 5578 if (FD->isBitField()) 5579 continue; 5580 if (FD->hasAttr<AlignedAttr>()) 5581 return true; 5582 if (Context.isAlignmentRequired(FD->getType())) 5583 return true; 5584 } 5585 } 5586 } 5587 5588 // Microsoft's link.exe doesn't support alignments greater than 32 bytes for 5589 // common symbols, so symbols with greater alignment requirements cannot be 5590 // common. 5591 // Other COFF linkers (ld.bfd and LLD) support arbitrary power-of-two 5592 // alignments for common symbols via the aligncomm directive, so this 5593 // restriction only applies to MSVC environments. 5594 if (Context.getTargetInfo().getTriple().isKnownWindowsMSVCEnvironment() && 5595 Context.getTypeAlignIfKnown(D->getType()) > 5596 Context.toBits(CharUnits::fromQuantity(32))) 5597 return true; 5598 5599 return false; 5600 } 5601 5602 llvm::GlobalValue::LinkageTypes 5603 CodeGenModule::getLLVMLinkageForDeclarator(const DeclaratorDecl *D, 5604 GVALinkage Linkage) { 5605 if (Linkage == GVA_Internal) 5606 return llvm::Function::InternalLinkage; 5607 5608 if (D->hasAttr<WeakAttr>()) 5609 return llvm::GlobalVariable::WeakAnyLinkage; 5610 5611 if (const auto *FD = D->getAsFunction()) 5612 if (FD->isMultiVersion() && Linkage == GVA_AvailableExternally) 5613 return llvm::GlobalVariable::LinkOnceAnyLinkage; 5614 5615 // We are guaranteed to have a strong definition somewhere else, 5616 // so we can use available_externally linkage. 5617 if (Linkage == GVA_AvailableExternally) 5618 return llvm::GlobalValue::AvailableExternallyLinkage; 5619 5620 // Note that Apple's kernel linker doesn't support symbol 5621 // coalescing, so we need to avoid linkonce and weak linkages there. 5622 // Normally, this means we just map to internal, but for explicit 5623 // instantiations we'll map to external. 5624 5625 // In C++, the compiler has to emit a definition in every translation unit 5626 // that references the function. We should use linkonce_odr because 5627 // a) if all references in this translation unit are optimized away, we 5628 // don't need to codegen it. b) if the function persists, it needs to be 5629 // merged with other definitions. c) C++ has the ODR, so we know the 5630 // definition is dependable. 5631 if (Linkage == GVA_DiscardableODR) 5632 return !Context.getLangOpts().AppleKext ? llvm::Function::LinkOnceODRLinkage 5633 : llvm::Function::InternalLinkage; 5634 5635 // An explicit instantiation of a template has weak linkage, since 5636 // explicit instantiations can occur in multiple translation units 5637 // and must all be equivalent. However, we are not allowed to 5638 // throw away these explicit instantiations. 5639 // 5640 // CUDA/HIP: For -fno-gpu-rdc case, device code is limited to one TU, 5641 // so say that CUDA templates are either external (for kernels) or internal. 5642 // This lets llvm perform aggressive inter-procedural optimizations. For 5643 // -fgpu-rdc case, device function calls across multiple TU's are allowed, 5644 // therefore we need to follow the normal linkage paradigm. 5645 if (Linkage == GVA_StrongODR) { 5646 if (getLangOpts().AppleKext) 5647 return llvm::Function::ExternalLinkage; 5648 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice && 5649 !getLangOpts().GPURelocatableDeviceCode) 5650 return D->hasAttr<CUDAGlobalAttr>() ? llvm::Function::ExternalLinkage 5651 : llvm::Function::InternalLinkage; 5652 return llvm::Function::WeakODRLinkage; 5653 } 5654 5655 // C++ doesn't have tentative definitions and thus cannot have common 5656 // linkage. 5657 if (!getLangOpts().CPlusPlus && isa<VarDecl>(D) && 5658 !isVarDeclStrongDefinition(Context, *this, cast<VarDecl>(D), 5659 CodeGenOpts.NoCommon)) 5660 return llvm::GlobalVariable::CommonLinkage; 5661 5662 // selectany symbols are externally visible, so use weak instead of 5663 // linkonce. MSVC optimizes away references to const selectany globals, so 5664 // all definitions should be the same and ODR linkage should be used. 5665 // http://msdn.microsoft.com/en-us/library/5tkz6s71.aspx 5666 if (D->hasAttr<SelectAnyAttr>()) 5667 return llvm::GlobalVariable::WeakODRLinkage; 5668 5669 // Otherwise, we have strong external linkage. 5670 assert(Linkage == GVA_StrongExternal); 5671 return llvm::GlobalVariable::ExternalLinkage; 5672 } 5673 5674 llvm::GlobalValue::LinkageTypes 5675 CodeGenModule::getLLVMLinkageVarDefinition(const VarDecl *VD) { 5676 GVALinkage Linkage = getContext().GetGVALinkageForVariable(VD); 5677 return getLLVMLinkageForDeclarator(VD, Linkage); 5678 } 5679 5680 /// Replace the uses of a function that was declared with a non-proto type. 5681 /// We want to silently drop extra arguments from call sites 5682 static void replaceUsesOfNonProtoConstant(llvm::Constant *old, 5683 llvm::Function *newFn) { 5684 // Fast path. 5685 if (old->use_empty()) return; 5686 5687 llvm::Type *newRetTy = newFn->getReturnType(); 5688 SmallVector<llvm::Value*, 4> newArgs; 5689 5690 for (llvm::Value::use_iterator ui = old->use_begin(), ue = old->use_end(); 5691 ui != ue; ) { 5692 llvm::Value::use_iterator use = ui++; // Increment before the use is erased. 5693 llvm::User *user = use->getUser(); 5694 5695 // Recognize and replace uses of bitcasts. Most calls to 5696 // unprototyped functions will use bitcasts. 5697 if (auto *bitcast = dyn_cast<llvm::ConstantExpr>(user)) { 5698 if (bitcast->getOpcode() == llvm::Instruction::BitCast) 5699 replaceUsesOfNonProtoConstant(bitcast, newFn); 5700 continue; 5701 } 5702 5703 // Recognize calls to the function. 5704 llvm::CallBase *callSite = dyn_cast<llvm::CallBase>(user); 5705 if (!callSite) continue; 5706 if (!callSite->isCallee(&*use)) 5707 continue; 5708 5709 // If the return types don't match exactly, then we can't 5710 // transform this call unless it's dead. 5711 if (callSite->getType() != newRetTy && !callSite->use_empty()) 5712 continue; 5713 5714 // Get the call site's attribute list. 5715 SmallVector<llvm::AttributeSet, 8> newArgAttrs; 5716 llvm::AttributeList oldAttrs = callSite->getAttributes(); 5717 5718 // If the function was passed too few arguments, don't transform. 5719 unsigned newNumArgs = newFn->arg_size(); 5720 if (callSite->arg_size() < newNumArgs) 5721 continue; 5722 5723 // If extra arguments were passed, we silently drop them. 5724 // If any of the types mismatch, we don't transform. 5725 unsigned argNo = 0; 5726 bool dontTransform = false; 5727 for (llvm::Argument &A : newFn->args()) { 5728 if (callSite->getArgOperand(argNo)->getType() != A.getType()) { 5729 dontTransform = true; 5730 break; 5731 } 5732 5733 // Add any parameter attributes. 5734 newArgAttrs.push_back(oldAttrs.getParamAttrs(argNo)); 5735 argNo++; 5736 } 5737 if (dontTransform) 5738 continue; 5739 5740 // Okay, we can transform this. Create the new call instruction and copy 5741 // over the required information. 5742 newArgs.append(callSite->arg_begin(), callSite->arg_begin() + argNo); 5743 5744 // Copy over any operand bundles. 5745 SmallVector<llvm::OperandBundleDef, 1> newBundles; 5746 callSite->getOperandBundlesAsDefs(newBundles); 5747 5748 llvm::CallBase *newCall; 5749 if (isa<llvm::CallInst>(callSite)) { 5750 newCall = 5751 llvm::CallInst::Create(newFn, newArgs, newBundles, "", callSite); 5752 } else { 5753 auto *oldInvoke = cast<llvm::InvokeInst>(callSite); 5754 newCall = llvm::InvokeInst::Create(newFn, oldInvoke->getNormalDest(), 5755 oldInvoke->getUnwindDest(), newArgs, 5756 newBundles, "", callSite); 5757 } 5758 newArgs.clear(); // for the next iteration 5759 5760 if (!newCall->getType()->isVoidTy()) 5761 newCall->takeName(callSite); 5762 newCall->setAttributes( 5763 llvm::AttributeList::get(newFn->getContext(), oldAttrs.getFnAttrs(), 5764 oldAttrs.getRetAttrs(), newArgAttrs)); 5765 newCall->setCallingConv(callSite->getCallingConv()); 5766 5767 // Finally, remove the old call, replacing any uses with the new one. 5768 if (!callSite->use_empty()) 5769 callSite->replaceAllUsesWith(newCall); 5770 5771 // Copy debug location attached to CI. 5772 if (callSite->getDebugLoc()) 5773 newCall->setDebugLoc(callSite->getDebugLoc()); 5774 5775 callSite->eraseFromParent(); 5776 } 5777 } 5778 5779 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we 5780 /// implement a function with no prototype, e.g. "int foo() {}". If there are 5781 /// existing call uses of the old function in the module, this adjusts them to 5782 /// call the new function directly. 5783 /// 5784 /// This is not just a cleanup: the always_inline pass requires direct calls to 5785 /// functions to be able to inline them. If there is a bitcast in the way, it 5786 /// won't inline them. Instcombine normally deletes these calls, but it isn't 5787 /// run at -O0. 5788 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 5789 llvm::Function *NewFn) { 5790 // If we're redefining a global as a function, don't transform it. 5791 if (!isa<llvm::Function>(Old)) return; 5792 5793 replaceUsesOfNonProtoConstant(Old, NewFn); 5794 } 5795 5796 void CodeGenModule::HandleCXXStaticMemberVarInstantiation(VarDecl *VD) { 5797 auto DK = VD->isThisDeclarationADefinition(); 5798 if (DK == VarDecl::Definition && VD->hasAttr<DLLImportAttr>()) 5799 return; 5800 5801 TemplateSpecializationKind TSK = VD->getTemplateSpecializationKind(); 5802 // If we have a definition, this might be a deferred decl. If the 5803 // instantiation is explicit, make sure we emit it at the end. 5804 if (VD->getDefinition() && TSK == TSK_ExplicitInstantiationDefinition) 5805 GetAddrOfGlobalVar(VD); 5806 5807 EmitTopLevelDecl(VD); 5808 } 5809 5810 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD, 5811 llvm::GlobalValue *GV) { 5812 const auto *D = cast<FunctionDecl>(GD.getDecl()); 5813 5814 // Compute the function info and LLVM type. 5815 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 5816 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 5817 5818 // Get or create the prototype for the function. 5819 if (!GV || (GV->getValueType() != Ty)) 5820 GV = cast<llvm::GlobalValue>(GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, 5821 /*DontDefer=*/true, 5822 ForDefinition)); 5823 5824 // Already emitted. 5825 if (!GV->isDeclaration()) 5826 return; 5827 5828 // We need to set linkage and visibility on the function before 5829 // generating code for it because various parts of IR generation 5830 // want to propagate this information down (e.g. to local static 5831 // declarations). 5832 auto *Fn = cast<llvm::Function>(GV); 5833 setFunctionLinkage(GD, Fn); 5834 5835 // FIXME: this is redundant with part of setFunctionDefinitionAttributes 5836 setGVProperties(Fn, GD); 5837 5838 MaybeHandleStaticInExternC(D, Fn); 5839 5840 maybeSetTrivialComdat(*D, *Fn); 5841 5842 CodeGenFunction(*this).GenerateCode(GD, Fn, FI); 5843 5844 setNonAliasAttributes(GD, Fn); 5845 SetLLVMFunctionAttributesForDefinition(D, Fn); 5846 5847 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>()) 5848 AddGlobalCtor(Fn, CA->getPriority()); 5849 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>()) 5850 AddGlobalDtor(Fn, DA->getPriority(), true); 5851 if (getLangOpts().OpenMP && D->hasAttr<OMPDeclareTargetDeclAttr>()) 5852 getOpenMPRuntime().emitDeclareTargetFunction(D, GV); 5853 } 5854 5855 void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) { 5856 const auto *D = cast<ValueDecl>(GD.getDecl()); 5857 const AliasAttr *AA = D->getAttr<AliasAttr>(); 5858 assert(AA && "Not an alias?"); 5859 5860 StringRef MangledName = getMangledName(GD); 5861 5862 if (AA->getAliasee() == MangledName) { 5863 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0; 5864 return; 5865 } 5866 5867 // If there is a definition in the module, then it wins over the alias. 5868 // This is dubious, but allow it to be safe. Just ignore the alias. 5869 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 5870 if (Entry && !Entry->isDeclaration()) 5871 return; 5872 5873 Aliases.push_back(GD); 5874 5875 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 5876 5877 // Create a reference to the named value. This ensures that it is emitted 5878 // if a deferred decl. 5879 llvm::Constant *Aliasee; 5880 llvm::GlobalValue::LinkageTypes LT; 5881 if (isa<llvm::FunctionType>(DeclTy)) { 5882 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GD, 5883 /*ForVTable=*/false); 5884 LT = getFunctionLinkage(GD); 5885 } else { 5886 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, LangAS::Default, 5887 /*D=*/nullptr); 5888 if (const auto *VD = dyn_cast<VarDecl>(GD.getDecl())) 5889 LT = getLLVMLinkageVarDefinition(VD); 5890 else 5891 LT = getFunctionLinkage(GD); 5892 } 5893 5894 // Create the new alias itself, but don't set a name yet. 5895 unsigned AS = Aliasee->getType()->getPointerAddressSpace(); 5896 auto *GA = 5897 llvm::GlobalAlias::create(DeclTy, AS, LT, "", Aliasee, &getModule()); 5898 5899 if (Entry) { 5900 if (GA->getAliasee() == Entry) { 5901 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0; 5902 return; 5903 } 5904 5905 assert(Entry->isDeclaration()); 5906 5907 // If there is a declaration in the module, then we had an extern followed 5908 // by the alias, as in: 5909 // extern int test6(); 5910 // ... 5911 // int test6() __attribute__((alias("test7"))); 5912 // 5913 // Remove it and replace uses of it with the alias. 5914 GA->takeName(Entry); 5915 5916 Entry->replaceAllUsesWith(GA); 5917 Entry->eraseFromParent(); 5918 } else { 5919 GA->setName(MangledName); 5920 } 5921 5922 // Set attributes which are particular to an alias; this is a 5923 // specialization of the attributes which may be set on a global 5924 // variable/function. 5925 if (D->hasAttr<WeakAttr>() || D->hasAttr<WeakRefAttr>() || 5926 D->isWeakImported()) { 5927 GA->setLinkage(llvm::Function::WeakAnyLinkage); 5928 } 5929 5930 if (const auto *VD = dyn_cast<VarDecl>(D)) 5931 if (VD->getTLSKind()) 5932 setTLSMode(GA, *VD); 5933 5934 SetCommonAttributes(GD, GA); 5935 5936 // Emit global alias debug information. 5937 if (isa<VarDecl>(D)) 5938 if (CGDebugInfo *DI = getModuleDebugInfo()) 5939 DI->EmitGlobalAlias(cast<llvm::GlobalValue>(GA->getAliasee()->stripPointerCasts()), GD); 5940 } 5941 5942 void CodeGenModule::emitIFuncDefinition(GlobalDecl GD) { 5943 const auto *D = cast<ValueDecl>(GD.getDecl()); 5944 const IFuncAttr *IFA = D->getAttr<IFuncAttr>(); 5945 assert(IFA && "Not an ifunc?"); 5946 5947 StringRef MangledName = getMangledName(GD); 5948 5949 if (IFA->getResolver() == MangledName) { 5950 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1; 5951 return; 5952 } 5953 5954 // Report an error if some definition overrides ifunc. 5955 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 5956 if (Entry && !Entry->isDeclaration()) { 5957 GlobalDecl OtherGD; 5958 if (lookupRepresentativeDecl(MangledName, OtherGD) && 5959 DiagnosedConflictingDefinitions.insert(GD).second) { 5960 Diags.Report(D->getLocation(), diag::err_duplicate_mangled_name) 5961 << MangledName; 5962 Diags.Report(OtherGD.getDecl()->getLocation(), 5963 diag::note_previous_definition); 5964 } 5965 return; 5966 } 5967 5968 Aliases.push_back(GD); 5969 5970 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 5971 llvm::Type *ResolverTy = llvm::GlobalIFunc::getResolverFunctionType(DeclTy); 5972 llvm::Constant *Resolver = 5973 GetOrCreateLLVMFunction(IFA->getResolver(), ResolverTy, {}, 5974 /*ForVTable=*/false); 5975 llvm::GlobalIFunc *GIF = 5976 llvm::GlobalIFunc::create(DeclTy, 0, llvm::Function::ExternalLinkage, 5977 "", Resolver, &getModule()); 5978 if (Entry) { 5979 if (GIF->getResolver() == Entry) { 5980 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1; 5981 return; 5982 } 5983 assert(Entry->isDeclaration()); 5984 5985 // If there is a declaration in the module, then we had an extern followed 5986 // by the ifunc, as in: 5987 // extern int test(); 5988 // ... 5989 // int test() __attribute__((ifunc("resolver"))); 5990 // 5991 // Remove it and replace uses of it with the ifunc. 5992 GIF->takeName(Entry); 5993 5994 Entry->replaceAllUsesWith(GIF); 5995 Entry->eraseFromParent(); 5996 } else 5997 GIF->setName(MangledName); 5998 if (auto *F = dyn_cast<llvm::Function>(Resolver)) { 5999 F->addFnAttr(llvm::Attribute::DisableSanitizerInstrumentation); 6000 } 6001 SetCommonAttributes(GD, GIF); 6002 } 6003 6004 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID, 6005 ArrayRef<llvm::Type*> Tys) { 6006 return llvm::Intrinsic::getDeclaration(&getModule(), (llvm::Intrinsic::ID)IID, 6007 Tys); 6008 } 6009 6010 static llvm::StringMapEntry<llvm::GlobalVariable *> & 6011 GetConstantCFStringEntry(llvm::StringMap<llvm::GlobalVariable *> &Map, 6012 const StringLiteral *Literal, bool TargetIsLSB, 6013 bool &IsUTF16, unsigned &StringLength) { 6014 StringRef String = Literal->getString(); 6015 unsigned NumBytes = String.size(); 6016 6017 // Check for simple case. 6018 if (!Literal->containsNonAsciiOrNull()) { 6019 StringLength = NumBytes; 6020 return *Map.insert(std::make_pair(String, nullptr)).first; 6021 } 6022 6023 // Otherwise, convert the UTF8 literals into a string of shorts. 6024 IsUTF16 = true; 6025 6026 SmallVector<llvm::UTF16, 128> ToBuf(NumBytes + 1); // +1 for ending nulls. 6027 const llvm::UTF8 *FromPtr = (const llvm::UTF8 *)String.data(); 6028 llvm::UTF16 *ToPtr = &ToBuf[0]; 6029 6030 (void)llvm::ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, &ToPtr, 6031 ToPtr + NumBytes, llvm::strictConversion); 6032 6033 // ConvertUTF8toUTF16 returns the length in ToPtr. 6034 StringLength = ToPtr - &ToBuf[0]; 6035 6036 // Add an explicit null. 6037 *ToPtr = 0; 6038 return *Map.insert(std::make_pair( 6039 StringRef(reinterpret_cast<const char *>(ToBuf.data()), 6040 (StringLength + 1) * 2), 6041 nullptr)).first; 6042 } 6043 6044 ConstantAddress 6045 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { 6046 unsigned StringLength = 0; 6047 bool isUTF16 = false; 6048 llvm::StringMapEntry<llvm::GlobalVariable *> &Entry = 6049 GetConstantCFStringEntry(CFConstantStringMap, Literal, 6050 getDataLayout().isLittleEndian(), isUTF16, 6051 StringLength); 6052 6053 if (auto *C = Entry.second) 6054 return ConstantAddress( 6055 C, C->getValueType(), CharUnits::fromQuantity(C->getAlignment())); 6056 6057 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty); 6058 llvm::Constant *Zeros[] = { Zero, Zero }; 6059 6060 const ASTContext &Context = getContext(); 6061 const llvm::Triple &Triple = getTriple(); 6062 6063 const auto CFRuntime = getLangOpts().CFRuntime; 6064 const bool IsSwiftABI = 6065 static_cast<unsigned>(CFRuntime) >= 6066 static_cast<unsigned>(LangOptions::CoreFoundationABI::Swift); 6067 const bool IsSwift4_1 = CFRuntime == LangOptions::CoreFoundationABI::Swift4_1; 6068 6069 // If we don't already have it, get __CFConstantStringClassReference. 6070 if (!CFConstantStringClassRef) { 6071 const char *CFConstantStringClassName = "__CFConstantStringClassReference"; 6072 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); 6073 Ty = llvm::ArrayType::get(Ty, 0); 6074 6075 switch (CFRuntime) { 6076 default: break; 6077 case LangOptions::CoreFoundationABI::Swift: [[fallthrough]]; 6078 case LangOptions::CoreFoundationABI::Swift5_0: 6079 CFConstantStringClassName = 6080 Triple.isOSDarwin() ? "$s15SwiftFoundation19_NSCFConstantStringCN" 6081 : "$s10Foundation19_NSCFConstantStringCN"; 6082 Ty = IntPtrTy; 6083 break; 6084 case LangOptions::CoreFoundationABI::Swift4_2: 6085 CFConstantStringClassName = 6086 Triple.isOSDarwin() ? "$S15SwiftFoundation19_NSCFConstantStringCN" 6087 : "$S10Foundation19_NSCFConstantStringCN"; 6088 Ty = IntPtrTy; 6089 break; 6090 case LangOptions::CoreFoundationABI::Swift4_1: 6091 CFConstantStringClassName = 6092 Triple.isOSDarwin() ? "__T015SwiftFoundation19_NSCFConstantStringCN" 6093 : "__T010Foundation19_NSCFConstantStringCN"; 6094 Ty = IntPtrTy; 6095 break; 6096 } 6097 6098 llvm::Constant *C = CreateRuntimeVariable(Ty, CFConstantStringClassName); 6099 6100 if (Triple.isOSBinFormatELF() || Triple.isOSBinFormatCOFF()) { 6101 llvm::GlobalValue *GV = nullptr; 6102 6103 if ((GV = dyn_cast<llvm::GlobalValue>(C))) { 6104 IdentifierInfo &II = Context.Idents.get(GV->getName()); 6105 TranslationUnitDecl *TUDecl = Context.getTranslationUnitDecl(); 6106 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); 6107 6108 const VarDecl *VD = nullptr; 6109 for (const auto *Result : DC->lookup(&II)) 6110 if ((VD = dyn_cast<VarDecl>(Result))) 6111 break; 6112 6113 if (Triple.isOSBinFormatELF()) { 6114 if (!VD) 6115 GV->setLinkage(llvm::GlobalValue::ExternalLinkage); 6116 } else { 6117 GV->setLinkage(llvm::GlobalValue::ExternalLinkage); 6118 if (!VD || !VD->hasAttr<DLLExportAttr>()) 6119 GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass); 6120 else 6121 GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass); 6122 } 6123 6124 setDSOLocal(GV); 6125 } 6126 } 6127 6128 // Decay array -> ptr 6129 CFConstantStringClassRef = 6130 IsSwiftABI ? llvm::ConstantExpr::getPtrToInt(C, Ty) 6131 : llvm::ConstantExpr::getGetElementPtr(Ty, C, Zeros); 6132 } 6133 6134 QualType CFTy = Context.getCFConstantStringType(); 6135 6136 auto *STy = cast<llvm::StructType>(getTypes().ConvertType(CFTy)); 6137 6138 ConstantInitBuilder Builder(*this); 6139 auto Fields = Builder.beginStruct(STy); 6140 6141 // Class pointer. 6142 Fields.add(cast<llvm::Constant>(CFConstantStringClassRef)); 6143 6144 // Flags. 6145 if (IsSwiftABI) { 6146 Fields.addInt(IntPtrTy, IsSwift4_1 ? 0x05 : 0x01); 6147 Fields.addInt(Int64Ty, isUTF16 ? 0x07d0 : 0x07c8); 6148 } else { 6149 Fields.addInt(IntTy, isUTF16 ? 0x07d0 : 0x07C8); 6150 } 6151 6152 // String pointer. 6153 llvm::Constant *C = nullptr; 6154 if (isUTF16) { 6155 auto Arr = llvm::ArrayRef( 6156 reinterpret_cast<uint16_t *>(const_cast<char *>(Entry.first().data())), 6157 Entry.first().size() / 2); 6158 C = llvm::ConstantDataArray::get(VMContext, Arr); 6159 } else { 6160 C = llvm::ConstantDataArray::getString(VMContext, Entry.first()); 6161 } 6162 6163 // Note: -fwritable-strings doesn't make the backing store strings of 6164 // CFStrings writable. 6165 auto *GV = 6166 new llvm::GlobalVariable(getModule(), C->getType(), /*isConstant=*/true, 6167 llvm::GlobalValue::PrivateLinkage, C, ".str"); 6168 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 6169 // Don't enforce the target's minimum global alignment, since the only use 6170 // of the string is via this class initializer. 6171 CharUnits Align = isUTF16 ? Context.getTypeAlignInChars(Context.ShortTy) 6172 : Context.getTypeAlignInChars(Context.CharTy); 6173 GV->setAlignment(Align.getAsAlign()); 6174 6175 // FIXME: We set the section explicitly to avoid a bug in ld64 224.1. 6176 // Without it LLVM can merge the string with a non unnamed_addr one during 6177 // LTO. Doing that changes the section it ends in, which surprises ld64. 6178 if (Triple.isOSBinFormatMachO()) 6179 GV->setSection(isUTF16 ? "__TEXT,__ustring" 6180 : "__TEXT,__cstring,cstring_literals"); 6181 // Make sure the literal ends up in .rodata to allow for safe ICF and for 6182 // the static linker to adjust permissions to read-only later on. 6183 else if (Triple.isOSBinFormatELF()) 6184 GV->setSection(".rodata"); 6185 6186 // String. 6187 llvm::Constant *Str = 6188 llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV, Zeros); 6189 6190 Fields.add(Str); 6191 6192 // String length. 6193 llvm::IntegerType *LengthTy = 6194 llvm::IntegerType::get(getModule().getContext(), 6195 Context.getTargetInfo().getLongWidth()); 6196 if (IsSwiftABI) { 6197 if (CFRuntime == LangOptions::CoreFoundationABI::Swift4_1 || 6198 CFRuntime == LangOptions::CoreFoundationABI::Swift4_2) 6199 LengthTy = Int32Ty; 6200 else 6201 LengthTy = IntPtrTy; 6202 } 6203 Fields.addInt(LengthTy, StringLength); 6204 6205 // Swift ABI requires 8-byte alignment to ensure that the _Atomic(uint64_t) is 6206 // properly aligned on 32-bit platforms. 6207 CharUnits Alignment = 6208 IsSwiftABI ? Context.toCharUnitsFromBits(64) : getPointerAlign(); 6209 6210 // The struct. 6211 GV = Fields.finishAndCreateGlobal("_unnamed_cfstring_", Alignment, 6212 /*isConstant=*/false, 6213 llvm::GlobalVariable::PrivateLinkage); 6214 GV->addAttribute("objc_arc_inert"); 6215 switch (Triple.getObjectFormat()) { 6216 case llvm::Triple::UnknownObjectFormat: 6217 llvm_unreachable("unknown file format"); 6218 case llvm::Triple::DXContainer: 6219 case llvm::Triple::GOFF: 6220 case llvm::Triple::SPIRV: 6221 case llvm::Triple::XCOFF: 6222 llvm_unreachable("unimplemented"); 6223 case llvm::Triple::COFF: 6224 case llvm::Triple::ELF: 6225 case llvm::Triple::Wasm: 6226 GV->setSection("cfstring"); 6227 break; 6228 case llvm::Triple::MachO: 6229 GV->setSection("__DATA,__cfstring"); 6230 break; 6231 } 6232 Entry.second = GV; 6233 6234 return ConstantAddress(GV, GV->getValueType(), Alignment); 6235 } 6236 6237 bool CodeGenModule::getExpressionLocationsEnabled() const { 6238 return !CodeGenOpts.EmitCodeView || CodeGenOpts.DebugColumnInfo; 6239 } 6240 6241 QualType CodeGenModule::getObjCFastEnumerationStateType() { 6242 if (ObjCFastEnumerationStateType.isNull()) { 6243 RecordDecl *D = Context.buildImplicitRecord("__objcFastEnumerationState"); 6244 D->startDefinition(); 6245 6246 QualType FieldTypes[] = { 6247 Context.UnsignedLongTy, Context.getPointerType(Context.getObjCIdType()), 6248 Context.getPointerType(Context.UnsignedLongTy), 6249 Context.getConstantArrayType(Context.UnsignedLongTy, llvm::APInt(32, 5), 6250 nullptr, ArraySizeModifier::Normal, 0)}; 6251 6252 for (size_t i = 0; i < 4; ++i) { 6253 FieldDecl *Field = FieldDecl::Create(Context, 6254 D, 6255 SourceLocation(), 6256 SourceLocation(), nullptr, 6257 FieldTypes[i], /*TInfo=*/nullptr, 6258 /*BitWidth=*/nullptr, 6259 /*Mutable=*/false, 6260 ICIS_NoInit); 6261 Field->setAccess(AS_public); 6262 D->addDecl(Field); 6263 } 6264 6265 D->completeDefinition(); 6266 ObjCFastEnumerationStateType = Context.getTagDeclType(D); 6267 } 6268 6269 return ObjCFastEnumerationStateType; 6270 } 6271 6272 llvm::Constant * 6273 CodeGenModule::GetConstantArrayFromStringLiteral(const StringLiteral *E) { 6274 assert(!E->getType()->isPointerType() && "Strings are always arrays"); 6275 6276 // Don't emit it as the address of the string, emit the string data itself 6277 // as an inline array. 6278 if (E->getCharByteWidth() == 1) { 6279 SmallString<64> Str(E->getString()); 6280 6281 // Resize the string to the right size, which is indicated by its type. 6282 const ConstantArrayType *CAT = Context.getAsConstantArrayType(E->getType()); 6283 assert(CAT && "String literal not of constant array type!"); 6284 Str.resize(CAT->getZExtSize()); 6285 return llvm::ConstantDataArray::getString(VMContext, Str, false); 6286 } 6287 6288 auto *AType = cast<llvm::ArrayType>(getTypes().ConvertType(E->getType())); 6289 llvm::Type *ElemTy = AType->getElementType(); 6290 unsigned NumElements = AType->getNumElements(); 6291 6292 // Wide strings have either 2-byte or 4-byte elements. 6293 if (ElemTy->getPrimitiveSizeInBits() == 16) { 6294 SmallVector<uint16_t, 32> Elements; 6295 Elements.reserve(NumElements); 6296 6297 for(unsigned i = 0, e = E->getLength(); i != e; ++i) 6298 Elements.push_back(E->getCodeUnit(i)); 6299 Elements.resize(NumElements); 6300 return llvm::ConstantDataArray::get(VMContext, Elements); 6301 } 6302 6303 assert(ElemTy->getPrimitiveSizeInBits() == 32); 6304 SmallVector<uint32_t, 32> Elements; 6305 Elements.reserve(NumElements); 6306 6307 for(unsigned i = 0, e = E->getLength(); i != e; ++i) 6308 Elements.push_back(E->getCodeUnit(i)); 6309 Elements.resize(NumElements); 6310 return llvm::ConstantDataArray::get(VMContext, Elements); 6311 } 6312 6313 static llvm::GlobalVariable * 6314 GenerateStringLiteral(llvm::Constant *C, llvm::GlobalValue::LinkageTypes LT, 6315 CodeGenModule &CGM, StringRef GlobalName, 6316 CharUnits Alignment) { 6317 unsigned AddrSpace = CGM.getContext().getTargetAddressSpace( 6318 CGM.GetGlobalConstantAddressSpace()); 6319 6320 llvm::Module &M = CGM.getModule(); 6321 // Create a global variable for this string 6322 auto *GV = new llvm::GlobalVariable( 6323 M, C->getType(), !CGM.getLangOpts().WritableStrings, LT, C, GlobalName, 6324 nullptr, llvm::GlobalVariable::NotThreadLocal, AddrSpace); 6325 GV->setAlignment(Alignment.getAsAlign()); 6326 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 6327 if (GV->isWeakForLinker()) { 6328 assert(CGM.supportsCOMDAT() && "Only COFF uses weak string literals"); 6329 GV->setComdat(M.getOrInsertComdat(GV->getName())); 6330 } 6331 CGM.setDSOLocal(GV); 6332 6333 return GV; 6334 } 6335 6336 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a 6337 /// constant array for the given string literal. 6338 ConstantAddress 6339 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S, 6340 StringRef Name) { 6341 CharUnits Alignment = 6342 getContext().getAlignOfGlobalVarInChars(S->getType(), /*VD=*/nullptr); 6343 6344 llvm::Constant *C = GetConstantArrayFromStringLiteral(S); 6345 llvm::GlobalVariable **Entry = nullptr; 6346 if (!LangOpts.WritableStrings) { 6347 Entry = &ConstantStringMap[C]; 6348 if (auto GV = *Entry) { 6349 if (uint64_t(Alignment.getQuantity()) > GV->getAlignment()) 6350 GV->setAlignment(Alignment.getAsAlign()); 6351 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6352 GV->getValueType(), Alignment); 6353 } 6354 } 6355 6356 SmallString<256> MangledNameBuffer; 6357 StringRef GlobalVariableName; 6358 llvm::GlobalValue::LinkageTypes LT; 6359 6360 // Mangle the string literal if that's how the ABI merges duplicate strings. 6361 // Don't do it if they are writable, since we don't want writes in one TU to 6362 // affect strings in another. 6363 if (getCXXABI().getMangleContext().shouldMangleStringLiteral(S) && 6364 !LangOpts.WritableStrings) { 6365 llvm::raw_svector_ostream Out(MangledNameBuffer); 6366 getCXXABI().getMangleContext().mangleStringLiteral(S, Out); 6367 LT = llvm::GlobalValue::LinkOnceODRLinkage; 6368 GlobalVariableName = MangledNameBuffer; 6369 } else { 6370 LT = llvm::GlobalValue::PrivateLinkage; 6371 GlobalVariableName = Name; 6372 } 6373 6374 auto GV = GenerateStringLiteral(C, LT, *this, GlobalVariableName, Alignment); 6375 6376 CGDebugInfo *DI = getModuleDebugInfo(); 6377 if (DI && getCodeGenOpts().hasReducedDebugInfo()) 6378 DI->AddStringLiteralDebugInfo(GV, S); 6379 6380 if (Entry) 6381 *Entry = GV; 6382 6383 SanitizerMD->reportGlobal(GV, S->getStrTokenLoc(0), "<string literal>"); 6384 6385 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6386 GV->getValueType(), Alignment); 6387 } 6388 6389 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant 6390 /// array for the given ObjCEncodeExpr node. 6391 ConstantAddress 6392 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) { 6393 std::string Str; 6394 getContext().getObjCEncodingForType(E->getEncodedType(), Str); 6395 6396 return GetAddrOfConstantCString(Str); 6397 } 6398 6399 /// GetAddrOfConstantCString - Returns a pointer to a character array containing 6400 /// the literal and a terminating '\0' character. 6401 /// The result has pointer to array type. 6402 ConstantAddress CodeGenModule::GetAddrOfConstantCString( 6403 const std::string &Str, const char *GlobalName) { 6404 StringRef StrWithNull(Str.c_str(), Str.size() + 1); 6405 CharUnits Alignment = getContext().getAlignOfGlobalVarInChars( 6406 getContext().CharTy, /*VD=*/nullptr); 6407 6408 llvm::Constant *C = 6409 llvm::ConstantDataArray::getString(getLLVMContext(), StrWithNull, false); 6410 6411 // Don't share any string literals if strings aren't constant. 6412 llvm::GlobalVariable **Entry = nullptr; 6413 if (!LangOpts.WritableStrings) { 6414 Entry = &ConstantStringMap[C]; 6415 if (auto GV = *Entry) { 6416 if (uint64_t(Alignment.getQuantity()) > GV->getAlignment()) 6417 GV->setAlignment(Alignment.getAsAlign()); 6418 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6419 GV->getValueType(), Alignment); 6420 } 6421 } 6422 6423 // Get the default prefix if a name wasn't specified. 6424 if (!GlobalName) 6425 GlobalName = ".str"; 6426 // Create a global variable for this. 6427 auto GV = GenerateStringLiteral(C, llvm::GlobalValue::PrivateLinkage, *this, 6428 GlobalName, Alignment); 6429 if (Entry) 6430 *Entry = GV; 6431 6432 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6433 GV->getValueType(), Alignment); 6434 } 6435 6436 ConstantAddress CodeGenModule::GetAddrOfGlobalTemporary( 6437 const MaterializeTemporaryExpr *E, const Expr *Init) { 6438 assert((E->getStorageDuration() == SD_Static || 6439 E->getStorageDuration() == SD_Thread) && "not a global temporary"); 6440 const auto *VD = cast<VarDecl>(E->getExtendingDecl()); 6441 6442 // If we're not materializing a subobject of the temporary, keep the 6443 // cv-qualifiers from the type of the MaterializeTemporaryExpr. 6444 QualType MaterializedType = Init->getType(); 6445 if (Init == E->getSubExpr()) 6446 MaterializedType = E->getType(); 6447 6448 CharUnits Align = getContext().getTypeAlignInChars(MaterializedType); 6449 6450 auto InsertResult = MaterializedGlobalTemporaryMap.insert({E, nullptr}); 6451 if (!InsertResult.second) { 6452 // We've seen this before: either we already created it or we're in the 6453 // process of doing so. 6454 if (!InsertResult.first->second) { 6455 // We recursively re-entered this function, probably during emission of 6456 // the initializer. Create a placeholder. We'll clean this up in the 6457 // outer call, at the end of this function. 6458 llvm::Type *Type = getTypes().ConvertTypeForMem(MaterializedType); 6459 InsertResult.first->second = new llvm::GlobalVariable( 6460 getModule(), Type, false, llvm::GlobalVariable::InternalLinkage, 6461 nullptr); 6462 } 6463 return ConstantAddress(InsertResult.first->second, 6464 llvm::cast<llvm::GlobalVariable>( 6465 InsertResult.first->second->stripPointerCasts()) 6466 ->getValueType(), 6467 Align); 6468 } 6469 6470 // FIXME: If an externally-visible declaration extends multiple temporaries, 6471 // we need to give each temporary the same name in every translation unit (and 6472 // we also need to make the temporaries externally-visible). 6473 SmallString<256> Name; 6474 llvm::raw_svector_ostream Out(Name); 6475 getCXXABI().getMangleContext().mangleReferenceTemporary( 6476 VD, E->getManglingNumber(), Out); 6477 6478 APValue *Value = nullptr; 6479 if (E->getStorageDuration() == SD_Static && VD->evaluateValue()) { 6480 // If the initializer of the extending declaration is a constant 6481 // initializer, we should have a cached constant initializer for this 6482 // temporary. Note that this might have a different value from the value 6483 // computed by evaluating the initializer if the surrounding constant 6484 // expression modifies the temporary. 6485 Value = E->getOrCreateValue(false); 6486 } 6487 6488 // Try evaluating it now, it might have a constant initializer. 6489 Expr::EvalResult EvalResult; 6490 if (!Value && Init->EvaluateAsRValue(EvalResult, getContext()) && 6491 !EvalResult.hasSideEffects()) 6492 Value = &EvalResult.Val; 6493 6494 LangAS AddrSpace = GetGlobalVarAddressSpace(VD); 6495 6496 std::optional<ConstantEmitter> emitter; 6497 llvm::Constant *InitialValue = nullptr; 6498 bool Constant = false; 6499 llvm::Type *Type; 6500 if (Value) { 6501 // The temporary has a constant initializer, use it. 6502 emitter.emplace(*this); 6503 InitialValue = emitter->emitForInitializer(*Value, AddrSpace, 6504 MaterializedType); 6505 Constant = 6506 MaterializedType.isConstantStorage(getContext(), /*ExcludeCtor*/ Value, 6507 /*ExcludeDtor*/ false); 6508 Type = InitialValue->getType(); 6509 } else { 6510 // No initializer, the initialization will be provided when we 6511 // initialize the declaration which performed lifetime extension. 6512 Type = getTypes().ConvertTypeForMem(MaterializedType); 6513 } 6514 6515 // Create a global variable for this lifetime-extended temporary. 6516 llvm::GlobalValue::LinkageTypes Linkage = getLLVMLinkageVarDefinition(VD); 6517 if (Linkage == llvm::GlobalVariable::ExternalLinkage) { 6518 const VarDecl *InitVD; 6519 if (VD->isStaticDataMember() && VD->getAnyInitializer(InitVD) && 6520 isa<CXXRecordDecl>(InitVD->getLexicalDeclContext())) { 6521 // Temporaries defined inside a class get linkonce_odr linkage because the 6522 // class can be defined in multiple translation units. 6523 Linkage = llvm::GlobalVariable::LinkOnceODRLinkage; 6524 } else { 6525 // There is no need for this temporary to have external linkage if the 6526 // VarDecl has external linkage. 6527 Linkage = llvm::GlobalVariable::InternalLinkage; 6528 } 6529 } 6530 auto TargetAS = getContext().getTargetAddressSpace(AddrSpace); 6531 auto *GV = new llvm::GlobalVariable( 6532 getModule(), Type, Constant, Linkage, InitialValue, Name.c_str(), 6533 /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal, TargetAS); 6534 if (emitter) emitter->finalize(GV); 6535 // Don't assign dllimport or dllexport to local linkage globals. 6536 if (!llvm::GlobalValue::isLocalLinkage(Linkage)) { 6537 setGVProperties(GV, VD); 6538 if (GV->getDLLStorageClass() == llvm::GlobalVariable::DLLExportStorageClass) 6539 // The reference temporary should never be dllexport. 6540 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass); 6541 } 6542 GV->setAlignment(Align.getAsAlign()); 6543 if (supportsCOMDAT() && GV->isWeakForLinker()) 6544 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 6545 if (VD->getTLSKind()) 6546 setTLSMode(GV, *VD); 6547 llvm::Constant *CV = GV; 6548 if (AddrSpace != LangAS::Default) 6549 CV = getTargetCodeGenInfo().performAddrSpaceCast( 6550 *this, GV, AddrSpace, LangAS::Default, 6551 llvm::PointerType::get( 6552 getLLVMContext(), 6553 getContext().getTargetAddressSpace(LangAS::Default))); 6554 6555 // Update the map with the new temporary. If we created a placeholder above, 6556 // replace it with the new global now. 6557 llvm::Constant *&Entry = MaterializedGlobalTemporaryMap[E]; 6558 if (Entry) { 6559 Entry->replaceAllUsesWith(CV); 6560 llvm::cast<llvm::GlobalVariable>(Entry)->eraseFromParent(); 6561 } 6562 Entry = CV; 6563 6564 return ConstantAddress(CV, Type, Align); 6565 } 6566 6567 /// EmitObjCPropertyImplementations - Emit information for synthesized 6568 /// properties for an implementation. 6569 void CodeGenModule::EmitObjCPropertyImplementations(const 6570 ObjCImplementationDecl *D) { 6571 for (const auto *PID : D->property_impls()) { 6572 // Dynamic is just for type-checking. 6573 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) { 6574 ObjCPropertyDecl *PD = PID->getPropertyDecl(); 6575 6576 // Determine which methods need to be implemented, some may have 6577 // been overridden. Note that ::isPropertyAccessor is not the method 6578 // we want, that just indicates if the decl came from a 6579 // property. What we want to know is if the method is defined in 6580 // this implementation. 6581 auto *Getter = PID->getGetterMethodDecl(); 6582 if (!Getter || Getter->isSynthesizedAccessorStub()) 6583 CodeGenFunction(*this).GenerateObjCGetter( 6584 const_cast<ObjCImplementationDecl *>(D), PID); 6585 auto *Setter = PID->getSetterMethodDecl(); 6586 if (!PD->isReadOnly() && (!Setter || Setter->isSynthesizedAccessorStub())) 6587 CodeGenFunction(*this).GenerateObjCSetter( 6588 const_cast<ObjCImplementationDecl *>(D), PID); 6589 } 6590 } 6591 } 6592 6593 static bool needsDestructMethod(ObjCImplementationDecl *impl) { 6594 const ObjCInterfaceDecl *iface = impl->getClassInterface(); 6595 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin(); 6596 ivar; ivar = ivar->getNextIvar()) 6597 if (ivar->getType().isDestructedType()) 6598 return true; 6599 6600 return false; 6601 } 6602 6603 static bool AllTrivialInitializers(CodeGenModule &CGM, 6604 ObjCImplementationDecl *D) { 6605 CodeGenFunction CGF(CGM); 6606 for (ObjCImplementationDecl::init_iterator B = D->init_begin(), 6607 E = D->init_end(); B != E; ++B) { 6608 CXXCtorInitializer *CtorInitExp = *B; 6609 Expr *Init = CtorInitExp->getInit(); 6610 if (!CGF.isTrivialInitializer(Init)) 6611 return false; 6612 } 6613 return true; 6614 } 6615 6616 /// EmitObjCIvarInitializations - Emit information for ivar initialization 6617 /// for an implementation. 6618 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) { 6619 // We might need a .cxx_destruct even if we don't have any ivar initializers. 6620 if (needsDestructMethod(D)) { 6621 IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct"); 6622 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 6623 ObjCMethodDecl *DTORMethod = ObjCMethodDecl::Create( 6624 getContext(), D->getLocation(), D->getLocation(), cxxSelector, 6625 getContext().VoidTy, nullptr, D, 6626 /*isInstance=*/true, /*isVariadic=*/false, 6627 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false, 6628 /*isImplicitlyDeclared=*/true, 6629 /*isDefined=*/false, ObjCImplementationControl::Required); 6630 D->addInstanceMethod(DTORMethod); 6631 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false); 6632 D->setHasDestructors(true); 6633 } 6634 6635 // If the implementation doesn't have any ivar initializers, we don't need 6636 // a .cxx_construct. 6637 if (D->getNumIvarInitializers() == 0 || 6638 AllTrivialInitializers(*this, D)) 6639 return; 6640 6641 IdentifierInfo *II = &getContext().Idents.get(".cxx_construct"); 6642 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 6643 // The constructor returns 'self'. 6644 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create( 6645 getContext(), D->getLocation(), D->getLocation(), cxxSelector, 6646 getContext().getObjCIdType(), nullptr, D, /*isInstance=*/true, 6647 /*isVariadic=*/false, 6648 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false, 6649 /*isImplicitlyDeclared=*/true, 6650 /*isDefined=*/false, ObjCImplementationControl::Required); 6651 D->addInstanceMethod(CTORMethod); 6652 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true); 6653 D->setHasNonZeroConstructors(true); 6654 } 6655 6656 // EmitLinkageSpec - Emit all declarations in a linkage spec. 6657 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) { 6658 if (LSD->getLanguage() != LinkageSpecLanguageIDs::C && 6659 LSD->getLanguage() != LinkageSpecLanguageIDs::CXX) { 6660 ErrorUnsupported(LSD, "linkage spec"); 6661 return; 6662 } 6663 6664 EmitDeclContext(LSD); 6665 } 6666 6667 void CodeGenModule::EmitTopLevelStmt(const TopLevelStmtDecl *D) { 6668 // Device code should not be at top level. 6669 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) 6670 return; 6671 6672 std::unique_ptr<CodeGenFunction> &CurCGF = 6673 GlobalTopLevelStmtBlockInFlight.first; 6674 6675 // We emitted a top-level stmt but after it there is initialization. 6676 // Stop squashing the top-level stmts into a single function. 6677 if (CurCGF && CXXGlobalInits.back() != CurCGF->CurFn) { 6678 CurCGF->FinishFunction(D->getEndLoc()); 6679 CurCGF = nullptr; 6680 } 6681 6682 if (!CurCGF) { 6683 // void __stmts__N(void) 6684 // FIXME: Ask the ABI name mangler to pick a name. 6685 std::string Name = "__stmts__" + llvm::utostr(CXXGlobalInits.size()); 6686 FunctionArgList Args; 6687 QualType RetTy = getContext().VoidTy; 6688 const CGFunctionInfo &FnInfo = 6689 getTypes().arrangeBuiltinFunctionDeclaration(RetTy, Args); 6690 llvm::FunctionType *FnTy = getTypes().GetFunctionType(FnInfo); 6691 llvm::Function *Fn = llvm::Function::Create( 6692 FnTy, llvm::GlobalValue::InternalLinkage, Name, &getModule()); 6693 6694 CurCGF.reset(new CodeGenFunction(*this)); 6695 GlobalTopLevelStmtBlockInFlight.second = D; 6696 CurCGF->StartFunction(GlobalDecl(), RetTy, Fn, FnInfo, Args, 6697 D->getBeginLoc(), D->getBeginLoc()); 6698 CXXGlobalInits.push_back(Fn); 6699 } 6700 6701 CurCGF->EmitStmt(D->getStmt()); 6702 } 6703 6704 void CodeGenModule::EmitDeclContext(const DeclContext *DC) { 6705 for (auto *I : DC->decls()) { 6706 // Unlike other DeclContexts, the contents of an ObjCImplDecl at TU scope 6707 // are themselves considered "top-level", so EmitTopLevelDecl on an 6708 // ObjCImplDecl does not recursively visit them. We need to do that in 6709 // case they're nested inside another construct (LinkageSpecDecl / 6710 // ExportDecl) that does stop them from being considered "top-level". 6711 if (auto *OID = dyn_cast<ObjCImplDecl>(I)) { 6712 for (auto *M : OID->methods()) 6713 EmitTopLevelDecl(M); 6714 } 6715 6716 EmitTopLevelDecl(I); 6717 } 6718 } 6719 6720 /// EmitTopLevelDecl - Emit code for a single top level declaration. 6721 void CodeGenModule::EmitTopLevelDecl(Decl *D) { 6722 // Ignore dependent declarations. 6723 if (D->isTemplated()) 6724 return; 6725 6726 // Consteval function shouldn't be emitted. 6727 if (auto *FD = dyn_cast<FunctionDecl>(D); FD && FD->isImmediateFunction()) 6728 return; 6729 6730 switch (D->getKind()) { 6731 case Decl::CXXConversion: 6732 case Decl::CXXMethod: 6733 case Decl::Function: 6734 EmitGlobal(cast<FunctionDecl>(D)); 6735 // Always provide some coverage mapping 6736 // even for the functions that aren't emitted. 6737 AddDeferredUnusedCoverageMapping(D); 6738 break; 6739 6740 case Decl::CXXDeductionGuide: 6741 // Function-like, but does not result in code emission. 6742 break; 6743 6744 case Decl::Var: 6745 case Decl::Decomposition: 6746 case Decl::VarTemplateSpecialization: 6747 EmitGlobal(cast<VarDecl>(D)); 6748 if (auto *DD = dyn_cast<DecompositionDecl>(D)) 6749 for (auto *B : DD->bindings()) 6750 if (auto *HD = B->getHoldingVar()) 6751 EmitGlobal(HD); 6752 break; 6753 6754 // Indirect fields from global anonymous structs and unions can be 6755 // ignored; only the actual variable requires IR gen support. 6756 case Decl::IndirectField: 6757 break; 6758 6759 // C++ Decls 6760 case Decl::Namespace: 6761 EmitDeclContext(cast<NamespaceDecl>(D)); 6762 break; 6763 case Decl::ClassTemplateSpecialization: { 6764 const auto *Spec = cast<ClassTemplateSpecializationDecl>(D); 6765 if (CGDebugInfo *DI = getModuleDebugInfo()) 6766 if (Spec->getSpecializationKind() == 6767 TSK_ExplicitInstantiationDefinition && 6768 Spec->hasDefinition()) 6769 DI->completeTemplateDefinition(*Spec); 6770 } [[fallthrough]]; 6771 case Decl::CXXRecord: { 6772 CXXRecordDecl *CRD = cast<CXXRecordDecl>(D); 6773 if (CGDebugInfo *DI = getModuleDebugInfo()) { 6774 if (CRD->hasDefinition()) 6775 DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D))); 6776 if (auto *ES = D->getASTContext().getExternalSource()) 6777 if (ES->hasExternalDefinitions(D) == ExternalASTSource::EK_Never) 6778 DI->completeUnusedClass(*CRD); 6779 } 6780 // Emit any static data members, they may be definitions. 6781 for (auto *I : CRD->decls()) 6782 if (isa<VarDecl>(I) || isa<CXXRecordDecl>(I)) 6783 EmitTopLevelDecl(I); 6784 break; 6785 } 6786 // No code generation needed. 6787 case Decl::UsingShadow: 6788 case Decl::ClassTemplate: 6789 case Decl::VarTemplate: 6790 case Decl::Concept: 6791 case Decl::VarTemplatePartialSpecialization: 6792 case Decl::FunctionTemplate: 6793 case Decl::TypeAliasTemplate: 6794 case Decl::Block: 6795 case Decl::Empty: 6796 case Decl::Binding: 6797 break; 6798 case Decl::Using: // using X; [C++] 6799 if (CGDebugInfo *DI = getModuleDebugInfo()) 6800 DI->EmitUsingDecl(cast<UsingDecl>(*D)); 6801 break; 6802 case Decl::UsingEnum: // using enum X; [C++] 6803 if (CGDebugInfo *DI = getModuleDebugInfo()) 6804 DI->EmitUsingEnumDecl(cast<UsingEnumDecl>(*D)); 6805 break; 6806 case Decl::NamespaceAlias: 6807 if (CGDebugInfo *DI = getModuleDebugInfo()) 6808 DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(*D)); 6809 break; 6810 case Decl::UsingDirective: // using namespace X; [C++] 6811 if (CGDebugInfo *DI = getModuleDebugInfo()) 6812 DI->EmitUsingDirective(cast<UsingDirectiveDecl>(*D)); 6813 break; 6814 case Decl::CXXConstructor: 6815 getCXXABI().EmitCXXConstructors(cast<CXXConstructorDecl>(D)); 6816 break; 6817 case Decl::CXXDestructor: 6818 getCXXABI().EmitCXXDestructors(cast<CXXDestructorDecl>(D)); 6819 break; 6820 6821 case Decl::StaticAssert: 6822 // Nothing to do. 6823 break; 6824 6825 // Objective-C Decls 6826 6827 // Forward declarations, no (immediate) code generation. 6828 case Decl::ObjCInterface: 6829 case Decl::ObjCCategory: 6830 break; 6831 6832 case Decl::ObjCProtocol: { 6833 auto *Proto = cast<ObjCProtocolDecl>(D); 6834 if (Proto->isThisDeclarationADefinition()) 6835 ObjCRuntime->GenerateProtocol(Proto); 6836 break; 6837 } 6838 6839 case Decl::ObjCCategoryImpl: 6840 // Categories have properties but don't support synthesize so we 6841 // can ignore them here. 6842 ObjCRuntime->GenerateCategory(cast<ObjCCategoryImplDecl>(D)); 6843 break; 6844 6845 case Decl::ObjCImplementation: { 6846 auto *OMD = cast<ObjCImplementationDecl>(D); 6847 EmitObjCPropertyImplementations(OMD); 6848 EmitObjCIvarInitializations(OMD); 6849 ObjCRuntime->GenerateClass(OMD); 6850 // Emit global variable debug information. 6851 if (CGDebugInfo *DI = getModuleDebugInfo()) 6852 if (getCodeGenOpts().hasReducedDebugInfo()) 6853 DI->getOrCreateInterfaceType(getContext().getObjCInterfaceType( 6854 OMD->getClassInterface()), OMD->getLocation()); 6855 break; 6856 } 6857 case Decl::ObjCMethod: { 6858 auto *OMD = cast<ObjCMethodDecl>(D); 6859 // If this is not a prototype, emit the body. 6860 if (OMD->getBody()) 6861 CodeGenFunction(*this).GenerateObjCMethod(OMD); 6862 break; 6863 } 6864 case Decl::ObjCCompatibleAlias: 6865 ObjCRuntime->RegisterAlias(cast<ObjCCompatibleAliasDecl>(D)); 6866 break; 6867 6868 case Decl::PragmaComment: { 6869 const auto *PCD = cast<PragmaCommentDecl>(D); 6870 switch (PCD->getCommentKind()) { 6871 case PCK_Unknown: 6872 llvm_unreachable("unexpected pragma comment kind"); 6873 case PCK_Linker: 6874 AppendLinkerOptions(PCD->getArg()); 6875 break; 6876 case PCK_Lib: 6877 AddDependentLib(PCD->getArg()); 6878 break; 6879 case PCK_Compiler: 6880 case PCK_ExeStr: 6881 case PCK_User: 6882 break; // We ignore all of these. 6883 } 6884 break; 6885 } 6886 6887 case Decl::PragmaDetectMismatch: { 6888 const auto *PDMD = cast<PragmaDetectMismatchDecl>(D); 6889 AddDetectMismatch(PDMD->getName(), PDMD->getValue()); 6890 break; 6891 } 6892 6893 case Decl::LinkageSpec: 6894 EmitLinkageSpec(cast<LinkageSpecDecl>(D)); 6895 break; 6896 6897 case Decl::FileScopeAsm: { 6898 // File-scope asm is ignored during device-side CUDA compilation. 6899 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) 6900 break; 6901 // File-scope asm is ignored during device-side OpenMP compilation. 6902 if (LangOpts.OpenMPIsTargetDevice) 6903 break; 6904 // File-scope asm is ignored during device-side SYCL compilation. 6905 if (LangOpts.SYCLIsDevice) 6906 break; 6907 auto *AD = cast<FileScopeAsmDecl>(D); 6908 getModule().appendModuleInlineAsm(AD->getAsmString()->getString()); 6909 break; 6910 } 6911 6912 case Decl::TopLevelStmt: 6913 EmitTopLevelStmt(cast<TopLevelStmtDecl>(D)); 6914 break; 6915 6916 case Decl::Import: { 6917 auto *Import = cast<ImportDecl>(D); 6918 6919 // If we've already imported this module, we're done. 6920 if (!ImportedModules.insert(Import->getImportedModule())) 6921 break; 6922 6923 // Emit debug information for direct imports. 6924 if (!Import->getImportedOwningModule()) { 6925 if (CGDebugInfo *DI = getModuleDebugInfo()) 6926 DI->EmitImportDecl(*Import); 6927 } 6928 6929 // For C++ standard modules we are done - we will call the module 6930 // initializer for imported modules, and that will likewise call those for 6931 // any imports it has. 6932 if (CXX20ModuleInits && Import->getImportedOwningModule() && 6933 !Import->getImportedOwningModule()->isModuleMapModule()) 6934 break; 6935 6936 // For clang C++ module map modules the initializers for sub-modules are 6937 // emitted here. 6938 6939 // Find all of the submodules and emit the module initializers. 6940 llvm::SmallPtrSet<clang::Module *, 16> Visited; 6941 SmallVector<clang::Module *, 16> Stack; 6942 Visited.insert(Import->getImportedModule()); 6943 Stack.push_back(Import->getImportedModule()); 6944 6945 while (!Stack.empty()) { 6946 clang::Module *Mod = Stack.pop_back_val(); 6947 if (!EmittedModuleInitializers.insert(Mod).second) 6948 continue; 6949 6950 for (auto *D : Context.getModuleInitializers(Mod)) 6951 EmitTopLevelDecl(D); 6952 6953 // Visit the submodules of this module. 6954 for (auto *Submodule : Mod->submodules()) { 6955 // Skip explicit children; they need to be explicitly imported to emit 6956 // the initializers. 6957 if (Submodule->IsExplicit) 6958 continue; 6959 6960 if (Visited.insert(Submodule).second) 6961 Stack.push_back(Submodule); 6962 } 6963 } 6964 break; 6965 } 6966 6967 case Decl::Export: 6968 EmitDeclContext(cast<ExportDecl>(D)); 6969 break; 6970 6971 case Decl::OMPThreadPrivate: 6972 EmitOMPThreadPrivateDecl(cast<OMPThreadPrivateDecl>(D)); 6973 break; 6974 6975 case Decl::OMPAllocate: 6976 EmitOMPAllocateDecl(cast<OMPAllocateDecl>(D)); 6977 break; 6978 6979 case Decl::OMPDeclareReduction: 6980 EmitOMPDeclareReduction(cast<OMPDeclareReductionDecl>(D)); 6981 break; 6982 6983 case Decl::OMPDeclareMapper: 6984 EmitOMPDeclareMapper(cast<OMPDeclareMapperDecl>(D)); 6985 break; 6986 6987 case Decl::OMPRequires: 6988 EmitOMPRequiresDecl(cast<OMPRequiresDecl>(D)); 6989 break; 6990 6991 case Decl::Typedef: 6992 case Decl::TypeAlias: // using foo = bar; [C++11] 6993 if (CGDebugInfo *DI = getModuleDebugInfo()) 6994 DI->EmitAndRetainType( 6995 getContext().getTypedefType(cast<TypedefNameDecl>(D))); 6996 break; 6997 6998 case Decl::Record: 6999 if (CGDebugInfo *DI = getModuleDebugInfo()) 7000 if (cast<RecordDecl>(D)->getDefinition()) 7001 DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D))); 7002 break; 7003 7004 case Decl::Enum: 7005 if (CGDebugInfo *DI = getModuleDebugInfo()) 7006 if (cast<EnumDecl>(D)->getDefinition()) 7007 DI->EmitAndRetainType(getContext().getEnumType(cast<EnumDecl>(D))); 7008 break; 7009 7010 case Decl::HLSLBuffer: 7011 getHLSLRuntime().addBuffer(cast<HLSLBufferDecl>(D)); 7012 break; 7013 7014 default: 7015 // Make sure we handled everything we should, every other kind is a 7016 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind 7017 // function. Need to recode Decl::Kind to do that easily. 7018 assert(isa<TypeDecl>(D) && "Unsupported decl kind"); 7019 break; 7020 } 7021 } 7022 7023 void CodeGenModule::AddDeferredUnusedCoverageMapping(Decl *D) { 7024 // Do we need to generate coverage mapping? 7025 if (!CodeGenOpts.CoverageMapping) 7026 return; 7027 switch (D->getKind()) { 7028 case Decl::CXXConversion: 7029 case Decl::CXXMethod: 7030 case Decl::Function: 7031 case Decl::ObjCMethod: 7032 case Decl::CXXConstructor: 7033 case Decl::CXXDestructor: { 7034 if (!cast<FunctionDecl>(D)->doesThisDeclarationHaveABody()) 7035 break; 7036 SourceManager &SM = getContext().getSourceManager(); 7037 if (LimitedCoverage && SM.getMainFileID() != SM.getFileID(D->getBeginLoc())) 7038 break; 7039 DeferredEmptyCoverageMappingDecls.try_emplace(D, true); 7040 break; 7041 } 7042 default: 7043 break; 7044 }; 7045 } 7046 7047 void CodeGenModule::ClearUnusedCoverageMapping(const Decl *D) { 7048 // Do we need to generate coverage mapping? 7049 if (!CodeGenOpts.CoverageMapping) 7050 return; 7051 if (const auto *Fn = dyn_cast<FunctionDecl>(D)) { 7052 if (Fn->isTemplateInstantiation()) 7053 ClearUnusedCoverageMapping(Fn->getTemplateInstantiationPattern()); 7054 } 7055 DeferredEmptyCoverageMappingDecls.insert_or_assign(D, false); 7056 } 7057 7058 void CodeGenModule::EmitDeferredUnusedCoverageMappings() { 7059 // We call takeVector() here to avoid use-after-free. 7060 // FIXME: DeferredEmptyCoverageMappingDecls is getting mutated because 7061 // we deserialize function bodies to emit coverage info for them, and that 7062 // deserializes more declarations. How should we handle that case? 7063 for (const auto &Entry : DeferredEmptyCoverageMappingDecls.takeVector()) { 7064 if (!Entry.second) 7065 continue; 7066 const Decl *D = Entry.first; 7067 switch (D->getKind()) { 7068 case Decl::CXXConversion: 7069 case Decl::CXXMethod: 7070 case Decl::Function: 7071 case Decl::ObjCMethod: { 7072 CodeGenPGO PGO(*this); 7073 GlobalDecl GD(cast<FunctionDecl>(D)); 7074 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 7075 getFunctionLinkage(GD)); 7076 break; 7077 } 7078 case Decl::CXXConstructor: { 7079 CodeGenPGO PGO(*this); 7080 GlobalDecl GD(cast<CXXConstructorDecl>(D), Ctor_Base); 7081 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 7082 getFunctionLinkage(GD)); 7083 break; 7084 } 7085 case Decl::CXXDestructor: { 7086 CodeGenPGO PGO(*this); 7087 GlobalDecl GD(cast<CXXDestructorDecl>(D), Dtor_Base); 7088 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 7089 getFunctionLinkage(GD)); 7090 break; 7091 } 7092 default: 7093 break; 7094 }; 7095 } 7096 } 7097 7098 void CodeGenModule::EmitMainVoidAlias() { 7099 // In order to transition away from "__original_main" gracefully, emit an 7100 // alias for "main" in the no-argument case so that libc can detect when 7101 // new-style no-argument main is in used. 7102 if (llvm::Function *F = getModule().getFunction("main")) { 7103 if (!F->isDeclaration() && F->arg_size() == 0 && !F->isVarArg() && 7104 F->getReturnType()->isIntegerTy(Context.getTargetInfo().getIntWidth())) { 7105 auto *GA = llvm::GlobalAlias::create("__main_void", F); 7106 GA->setVisibility(llvm::GlobalValue::HiddenVisibility); 7107 } 7108 } 7109 } 7110 7111 /// Turns the given pointer into a constant. 7112 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context, 7113 const void *Ptr) { 7114 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr); 7115 llvm::Type *i64 = llvm::Type::getInt64Ty(Context); 7116 return llvm::ConstantInt::get(i64, PtrInt); 7117 } 7118 7119 static void EmitGlobalDeclMetadata(CodeGenModule &CGM, 7120 llvm::NamedMDNode *&GlobalMetadata, 7121 GlobalDecl D, 7122 llvm::GlobalValue *Addr) { 7123 if (!GlobalMetadata) 7124 GlobalMetadata = 7125 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs"); 7126 7127 // TODO: should we report variant information for ctors/dtors? 7128 llvm::Metadata *Ops[] = {llvm::ConstantAsMetadata::get(Addr), 7129 llvm::ConstantAsMetadata::get(GetPointerConstant( 7130 CGM.getLLVMContext(), D.getDecl()))}; 7131 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops)); 7132 } 7133 7134 bool CodeGenModule::CheckAndReplaceExternCIFuncs(llvm::GlobalValue *Elem, 7135 llvm::GlobalValue *CppFunc) { 7136 // Store the list of ifuncs we need to replace uses in. 7137 llvm::SmallVector<llvm::GlobalIFunc *> IFuncs; 7138 // List of ConstantExprs that we should be able to delete when we're done 7139 // here. 7140 llvm::SmallVector<llvm::ConstantExpr *> CEs; 7141 7142 // It isn't valid to replace the extern-C ifuncs if all we find is itself! 7143 if (Elem == CppFunc) 7144 return false; 7145 7146 // First make sure that all users of this are ifuncs (or ifuncs via a 7147 // bitcast), and collect the list of ifuncs and CEs so we can work on them 7148 // later. 7149 for (llvm::User *User : Elem->users()) { 7150 // Users can either be a bitcast ConstExpr that is used by the ifuncs, OR an 7151 // ifunc directly. In any other case, just give up, as we don't know what we 7152 // could break by changing those. 7153 if (auto *ConstExpr = dyn_cast<llvm::ConstantExpr>(User)) { 7154 if (ConstExpr->getOpcode() != llvm::Instruction::BitCast) 7155 return false; 7156 7157 for (llvm::User *CEUser : ConstExpr->users()) { 7158 if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(CEUser)) { 7159 IFuncs.push_back(IFunc); 7160 } else { 7161 return false; 7162 } 7163 } 7164 CEs.push_back(ConstExpr); 7165 } else if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(User)) { 7166 IFuncs.push_back(IFunc); 7167 } else { 7168 // This user is one we don't know how to handle, so fail redirection. This 7169 // will result in an ifunc retaining a resolver name that will ultimately 7170 // fail to be resolved to a defined function. 7171 return false; 7172 } 7173 } 7174 7175 // Now we know this is a valid case where we can do this alias replacement, we 7176 // need to remove all of the references to Elem (and the bitcasts!) so we can 7177 // delete it. 7178 for (llvm::GlobalIFunc *IFunc : IFuncs) 7179 IFunc->setResolver(nullptr); 7180 for (llvm::ConstantExpr *ConstExpr : CEs) 7181 ConstExpr->destroyConstant(); 7182 7183 // We should now be out of uses for the 'old' version of this function, so we 7184 // can erase it as well. 7185 Elem->eraseFromParent(); 7186 7187 for (llvm::GlobalIFunc *IFunc : IFuncs) { 7188 // The type of the resolver is always just a function-type that returns the 7189 // type of the IFunc, so create that here. If the type of the actual 7190 // resolver doesn't match, it just gets bitcast to the right thing. 7191 auto *ResolverTy = 7192 llvm::FunctionType::get(IFunc->getType(), /*isVarArg*/ false); 7193 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 7194 CppFunc->getName(), ResolverTy, {}, /*ForVTable*/ false); 7195 IFunc->setResolver(Resolver); 7196 } 7197 return true; 7198 } 7199 7200 /// For each function which is declared within an extern "C" region and marked 7201 /// as 'used', but has internal linkage, create an alias from the unmangled 7202 /// name to the mangled name if possible. People expect to be able to refer 7203 /// to such functions with an unmangled name from inline assembly within the 7204 /// same translation unit. 7205 void CodeGenModule::EmitStaticExternCAliases() { 7206 if (!getTargetCodeGenInfo().shouldEmitStaticExternCAliases()) 7207 return; 7208 for (auto &I : StaticExternCValues) { 7209 IdentifierInfo *Name = I.first; 7210 llvm::GlobalValue *Val = I.second; 7211 7212 // If Val is null, that implies there were multiple declarations that each 7213 // had a claim to the unmangled name. In this case, generation of the alias 7214 // is suppressed. See CodeGenModule::MaybeHandleStaticInExternC. 7215 if (!Val) 7216 break; 7217 7218 llvm::GlobalValue *ExistingElem = 7219 getModule().getNamedValue(Name->getName()); 7220 7221 // If there is either not something already by this name, or we were able to 7222 // replace all uses from IFuncs, create the alias. 7223 if (!ExistingElem || CheckAndReplaceExternCIFuncs(ExistingElem, Val)) 7224 addCompilerUsedGlobal(llvm::GlobalAlias::create(Name->getName(), Val)); 7225 } 7226 } 7227 7228 bool CodeGenModule::lookupRepresentativeDecl(StringRef MangledName, 7229 GlobalDecl &Result) const { 7230 auto Res = Manglings.find(MangledName); 7231 if (Res == Manglings.end()) 7232 return false; 7233 Result = Res->getValue(); 7234 return true; 7235 } 7236 7237 /// Emits metadata nodes associating all the global values in the 7238 /// current module with the Decls they came from. This is useful for 7239 /// projects using IR gen as a subroutine. 7240 /// 7241 /// Since there's currently no way to associate an MDNode directly 7242 /// with an llvm::GlobalValue, we create a global named metadata 7243 /// with the name 'clang.global.decl.ptrs'. 7244 void CodeGenModule::EmitDeclMetadata() { 7245 llvm::NamedMDNode *GlobalMetadata = nullptr; 7246 7247 for (auto &I : MangledDeclNames) { 7248 llvm::GlobalValue *Addr = getModule().getNamedValue(I.second); 7249 // Some mangled names don't necessarily have an associated GlobalValue 7250 // in this module, e.g. if we mangled it for DebugInfo. 7251 if (Addr) 7252 EmitGlobalDeclMetadata(*this, GlobalMetadata, I.first, Addr); 7253 } 7254 } 7255 7256 /// Emits metadata nodes for all the local variables in the current 7257 /// function. 7258 void CodeGenFunction::EmitDeclMetadata() { 7259 if (LocalDeclMap.empty()) return; 7260 7261 llvm::LLVMContext &Context = getLLVMContext(); 7262 7263 // Find the unique metadata ID for this name. 7264 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr"); 7265 7266 llvm::NamedMDNode *GlobalMetadata = nullptr; 7267 7268 for (auto &I : LocalDeclMap) { 7269 const Decl *D = I.first; 7270 llvm::Value *Addr = I.second.emitRawPointer(*this); 7271 if (auto *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) { 7272 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D); 7273 Alloca->setMetadata( 7274 DeclPtrKind, llvm::MDNode::get( 7275 Context, llvm::ValueAsMetadata::getConstant(DAddr))); 7276 } else if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr)) { 7277 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D)); 7278 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV); 7279 } 7280 } 7281 } 7282 7283 void CodeGenModule::EmitVersionIdentMetadata() { 7284 llvm::NamedMDNode *IdentMetadata = 7285 TheModule.getOrInsertNamedMetadata("llvm.ident"); 7286 std::string Version = getClangFullVersion(); 7287 llvm::LLVMContext &Ctx = TheModule.getContext(); 7288 7289 llvm::Metadata *IdentNode[] = {llvm::MDString::get(Ctx, Version)}; 7290 IdentMetadata->addOperand(llvm::MDNode::get(Ctx, IdentNode)); 7291 } 7292 7293 void CodeGenModule::EmitCommandLineMetadata() { 7294 llvm::NamedMDNode *CommandLineMetadata = 7295 TheModule.getOrInsertNamedMetadata("llvm.commandline"); 7296 std::string CommandLine = getCodeGenOpts().RecordCommandLine; 7297 llvm::LLVMContext &Ctx = TheModule.getContext(); 7298 7299 llvm::Metadata *CommandLineNode[] = {llvm::MDString::get(Ctx, CommandLine)}; 7300 CommandLineMetadata->addOperand(llvm::MDNode::get(Ctx, CommandLineNode)); 7301 } 7302 7303 void CodeGenModule::EmitCoverageFile() { 7304 llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu"); 7305 if (!CUNode) 7306 return; 7307 7308 llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov"); 7309 llvm::LLVMContext &Ctx = TheModule.getContext(); 7310 auto *CoverageDataFile = 7311 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageDataFile); 7312 auto *CoverageNotesFile = 7313 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageNotesFile); 7314 for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) { 7315 llvm::MDNode *CU = CUNode->getOperand(i); 7316 llvm::Metadata *Elts[] = {CoverageNotesFile, CoverageDataFile, CU}; 7317 GCov->addOperand(llvm::MDNode::get(Ctx, Elts)); 7318 } 7319 } 7320 7321 llvm::Constant *CodeGenModule::GetAddrOfRTTIDescriptor(QualType Ty, 7322 bool ForEH) { 7323 // Return a bogus pointer if RTTI is disabled, unless it's for EH. 7324 // FIXME: should we even be calling this method if RTTI is disabled 7325 // and it's not for EH? 7326 if (!shouldEmitRTTI(ForEH)) 7327 return llvm::Constant::getNullValue(GlobalsInt8PtrTy); 7328 7329 if (ForEH && Ty->isObjCObjectPointerType() && 7330 LangOpts.ObjCRuntime.isGNUFamily()) 7331 return ObjCRuntime->GetEHType(Ty); 7332 7333 return getCXXABI().getAddrOfRTTIDescriptor(Ty); 7334 } 7335 7336 void CodeGenModule::EmitOMPThreadPrivateDecl(const OMPThreadPrivateDecl *D) { 7337 // Do not emit threadprivates in simd-only mode. 7338 if (LangOpts.OpenMP && LangOpts.OpenMPSimd) 7339 return; 7340 for (auto RefExpr : D->varlists()) { 7341 auto *VD = cast<VarDecl>(cast<DeclRefExpr>(RefExpr)->getDecl()); 7342 bool PerformInit = 7343 VD->getAnyInitializer() && 7344 !VD->getAnyInitializer()->isConstantInitializer(getContext(), 7345 /*ForRef=*/false); 7346 7347 Address Addr(GetAddrOfGlobalVar(VD), 7348 getTypes().ConvertTypeForMem(VD->getType()), 7349 getContext().getDeclAlign(VD)); 7350 if (auto InitFunction = getOpenMPRuntime().emitThreadPrivateVarDefinition( 7351 VD, Addr, RefExpr->getBeginLoc(), PerformInit)) 7352 CXXGlobalInits.push_back(InitFunction); 7353 } 7354 } 7355 7356 llvm::Metadata * 7357 CodeGenModule::CreateMetadataIdentifierImpl(QualType T, MetadataTypeMap &Map, 7358 StringRef Suffix) { 7359 if (auto *FnType = T->getAs<FunctionProtoType>()) 7360 T = getContext().getFunctionType( 7361 FnType->getReturnType(), FnType->getParamTypes(), 7362 FnType->getExtProtoInfo().withExceptionSpec(EST_None)); 7363 7364 llvm::Metadata *&InternalId = Map[T.getCanonicalType()]; 7365 if (InternalId) 7366 return InternalId; 7367 7368 if (isExternallyVisible(T->getLinkage())) { 7369 std::string OutName; 7370 llvm::raw_string_ostream Out(OutName); 7371 getCXXABI().getMangleContext().mangleCanonicalTypeName( 7372 T, Out, getCodeGenOpts().SanitizeCfiICallNormalizeIntegers); 7373 7374 if (getCodeGenOpts().SanitizeCfiICallNormalizeIntegers) 7375 Out << ".normalized"; 7376 7377 Out << Suffix; 7378 7379 InternalId = llvm::MDString::get(getLLVMContext(), Out.str()); 7380 } else { 7381 InternalId = llvm::MDNode::getDistinct(getLLVMContext(), 7382 llvm::ArrayRef<llvm::Metadata *>()); 7383 } 7384 7385 return InternalId; 7386 } 7387 7388 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierForType(QualType T) { 7389 return CreateMetadataIdentifierImpl(T, MetadataIdMap, ""); 7390 } 7391 7392 llvm::Metadata * 7393 CodeGenModule::CreateMetadataIdentifierForVirtualMemPtrType(QualType T) { 7394 return CreateMetadataIdentifierImpl(T, VirtualMetadataIdMap, ".virtual"); 7395 } 7396 7397 // Generalize pointer types to a void pointer with the qualifiers of the 7398 // originally pointed-to type, e.g. 'const char *' and 'char * const *' 7399 // generalize to 'const void *' while 'char *' and 'const char **' generalize to 7400 // 'void *'. 7401 static QualType GeneralizeType(ASTContext &Ctx, QualType Ty) { 7402 if (!Ty->isPointerType()) 7403 return Ty; 7404 7405 return Ctx.getPointerType( 7406 QualType(Ctx.VoidTy).withCVRQualifiers( 7407 Ty->getPointeeType().getCVRQualifiers())); 7408 } 7409 7410 // Apply type generalization to a FunctionType's return and argument types 7411 static QualType GeneralizeFunctionType(ASTContext &Ctx, QualType Ty) { 7412 if (auto *FnType = Ty->getAs<FunctionProtoType>()) { 7413 SmallVector<QualType, 8> GeneralizedParams; 7414 for (auto &Param : FnType->param_types()) 7415 GeneralizedParams.push_back(GeneralizeType(Ctx, Param)); 7416 7417 return Ctx.getFunctionType( 7418 GeneralizeType(Ctx, FnType->getReturnType()), 7419 GeneralizedParams, FnType->getExtProtoInfo()); 7420 } 7421 7422 if (auto *FnType = Ty->getAs<FunctionNoProtoType>()) 7423 return Ctx.getFunctionNoProtoType( 7424 GeneralizeType(Ctx, FnType->getReturnType())); 7425 7426 llvm_unreachable("Encountered unknown FunctionType"); 7427 } 7428 7429 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierGeneralized(QualType T) { 7430 return CreateMetadataIdentifierImpl(GeneralizeFunctionType(getContext(), T), 7431 GeneralizedMetadataIdMap, ".generalized"); 7432 } 7433 7434 /// Returns whether this module needs the "all-vtables" type identifier. 7435 bool CodeGenModule::NeedAllVtablesTypeId() const { 7436 // Returns true if at least one of vtable-based CFI checkers is enabled and 7437 // is not in the trapping mode. 7438 return ((LangOpts.Sanitize.has(SanitizerKind::CFIVCall) && 7439 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIVCall)) || 7440 (LangOpts.Sanitize.has(SanitizerKind::CFINVCall) && 7441 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFINVCall)) || 7442 (LangOpts.Sanitize.has(SanitizerKind::CFIDerivedCast) && 7443 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIDerivedCast)) || 7444 (LangOpts.Sanitize.has(SanitizerKind::CFIUnrelatedCast) && 7445 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIUnrelatedCast))); 7446 } 7447 7448 void CodeGenModule::AddVTableTypeMetadata(llvm::GlobalVariable *VTable, 7449 CharUnits Offset, 7450 const CXXRecordDecl *RD) { 7451 llvm::Metadata *MD = 7452 CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0)); 7453 VTable->addTypeMetadata(Offset.getQuantity(), MD); 7454 7455 if (CodeGenOpts.SanitizeCfiCrossDso) 7456 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD)) 7457 VTable->addTypeMetadata(Offset.getQuantity(), 7458 llvm::ConstantAsMetadata::get(CrossDsoTypeId)); 7459 7460 if (NeedAllVtablesTypeId()) { 7461 llvm::Metadata *MD = llvm::MDString::get(getLLVMContext(), "all-vtables"); 7462 VTable->addTypeMetadata(Offset.getQuantity(), MD); 7463 } 7464 } 7465 7466 llvm::SanitizerStatReport &CodeGenModule::getSanStats() { 7467 if (!SanStats) 7468 SanStats = std::make_unique<llvm::SanitizerStatReport>(&getModule()); 7469 7470 return *SanStats; 7471 } 7472 7473 llvm::Value * 7474 CodeGenModule::createOpenCLIntToSamplerConversion(const Expr *E, 7475 CodeGenFunction &CGF) { 7476 llvm::Constant *C = ConstantEmitter(CGF).emitAbstract(E, E->getType()); 7477 auto *SamplerT = getOpenCLRuntime().getSamplerType(E->getType().getTypePtr()); 7478 auto *FTy = llvm::FunctionType::get(SamplerT, {C->getType()}, false); 7479 auto *Call = CGF.EmitRuntimeCall( 7480 CreateRuntimeFunction(FTy, "__translate_sampler_initializer"), {C}); 7481 return Call; 7482 } 7483 7484 CharUnits CodeGenModule::getNaturalPointeeTypeAlignment( 7485 QualType T, LValueBaseInfo *BaseInfo, TBAAAccessInfo *TBAAInfo) { 7486 return getNaturalTypeAlignment(T->getPointeeType(), BaseInfo, TBAAInfo, 7487 /* forPointeeType= */ true); 7488 } 7489 7490 CharUnits CodeGenModule::getNaturalTypeAlignment(QualType T, 7491 LValueBaseInfo *BaseInfo, 7492 TBAAAccessInfo *TBAAInfo, 7493 bool forPointeeType) { 7494 if (TBAAInfo) 7495 *TBAAInfo = getTBAAAccessInfo(T); 7496 7497 // FIXME: This duplicates logic in ASTContext::getTypeAlignIfKnown. But 7498 // that doesn't return the information we need to compute BaseInfo. 7499 7500 // Honor alignment typedef attributes even on incomplete types. 7501 // We also honor them straight for C++ class types, even as pointees; 7502 // there's an expressivity gap here. 7503 if (auto TT = T->getAs<TypedefType>()) { 7504 if (auto Align = TT->getDecl()->getMaxAlignment()) { 7505 if (BaseInfo) 7506 *BaseInfo = LValueBaseInfo(AlignmentSource::AttributedType); 7507 return getContext().toCharUnitsFromBits(Align); 7508 } 7509 } 7510 7511 bool AlignForArray = T->isArrayType(); 7512 7513 // Analyze the base element type, so we don't get confused by incomplete 7514 // array types. 7515 T = getContext().getBaseElementType(T); 7516 7517 if (T->isIncompleteType()) { 7518 // We could try to replicate the logic from 7519 // ASTContext::getTypeAlignIfKnown, but nothing uses the alignment if the 7520 // type is incomplete, so it's impossible to test. We could try to reuse 7521 // getTypeAlignIfKnown, but that doesn't return the information we need 7522 // to set BaseInfo. So just ignore the possibility that the alignment is 7523 // greater than one. 7524 if (BaseInfo) 7525 *BaseInfo = LValueBaseInfo(AlignmentSource::Type); 7526 return CharUnits::One(); 7527 } 7528 7529 if (BaseInfo) 7530 *BaseInfo = LValueBaseInfo(AlignmentSource::Type); 7531 7532 CharUnits Alignment; 7533 const CXXRecordDecl *RD; 7534 if (T.getQualifiers().hasUnaligned()) { 7535 Alignment = CharUnits::One(); 7536 } else if (forPointeeType && !AlignForArray && 7537 (RD = T->getAsCXXRecordDecl())) { 7538 // For C++ class pointees, we don't know whether we're pointing at a 7539 // base or a complete object, so we generally need to use the 7540 // non-virtual alignment. 7541 Alignment = getClassPointerAlignment(RD); 7542 } else { 7543 Alignment = getContext().getTypeAlignInChars(T); 7544 } 7545 7546 // Cap to the global maximum type alignment unless the alignment 7547 // was somehow explicit on the type. 7548 if (unsigned MaxAlign = getLangOpts().MaxTypeAlign) { 7549 if (Alignment.getQuantity() > MaxAlign && 7550 !getContext().isAlignmentRequired(T)) 7551 Alignment = CharUnits::fromQuantity(MaxAlign); 7552 } 7553 return Alignment; 7554 } 7555 7556 bool CodeGenModule::stopAutoInit() { 7557 unsigned StopAfter = getContext().getLangOpts().TrivialAutoVarInitStopAfter; 7558 if (StopAfter) { 7559 // This number is positive only when -ftrivial-auto-var-init-stop-after=* is 7560 // used 7561 if (NumAutoVarInit >= StopAfter) { 7562 return true; 7563 } 7564 if (!NumAutoVarInit) { 7565 unsigned DiagID = getDiags().getCustomDiagID( 7566 DiagnosticsEngine::Warning, 7567 "-ftrivial-auto-var-init-stop-after=%0 has been enabled to limit the " 7568 "number of times ftrivial-auto-var-init=%1 gets applied."); 7569 getDiags().Report(DiagID) 7570 << StopAfter 7571 << (getContext().getLangOpts().getTrivialAutoVarInit() == 7572 LangOptions::TrivialAutoVarInitKind::Zero 7573 ? "zero" 7574 : "pattern"); 7575 } 7576 ++NumAutoVarInit; 7577 } 7578 return false; 7579 } 7580 7581 void CodeGenModule::printPostfixForExternalizedDecl(llvm::raw_ostream &OS, 7582 const Decl *D) const { 7583 // ptxas does not allow '.' in symbol names. On the other hand, HIP prefers 7584 // postfix beginning with '.' since the symbol name can be demangled. 7585 if (LangOpts.HIP) 7586 OS << (isa<VarDecl>(D) ? ".static." : ".intern."); 7587 else 7588 OS << (isa<VarDecl>(D) ? "__static__" : "__intern__"); 7589 7590 // If the CUID is not specified we try to generate a unique postfix. 7591 if (getLangOpts().CUID.empty()) { 7592 SourceManager &SM = getContext().getSourceManager(); 7593 PresumedLoc PLoc = SM.getPresumedLoc(D->getLocation()); 7594 assert(PLoc.isValid() && "Source location is expected to be valid."); 7595 7596 // Get the hash of the user defined macros. 7597 llvm::MD5 Hash; 7598 llvm::MD5::MD5Result Result; 7599 for (const auto &Arg : PreprocessorOpts.Macros) 7600 Hash.update(Arg.first); 7601 Hash.final(Result); 7602 7603 // Get the UniqueID for the file containing the decl. 7604 llvm::sys::fs::UniqueID ID; 7605 if (llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID)) { 7606 PLoc = SM.getPresumedLoc(D->getLocation(), /*UseLineDirectives=*/false); 7607 assert(PLoc.isValid() && "Source location is expected to be valid."); 7608 if (auto EC = llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID)) 7609 SM.getDiagnostics().Report(diag::err_cannot_open_file) 7610 << PLoc.getFilename() << EC.message(); 7611 } 7612 OS << llvm::format("%x", ID.getFile()) << llvm::format("%x", ID.getDevice()) 7613 << "_" << llvm::utohexstr(Result.low(), /*LowerCase=*/true, /*Width=*/8); 7614 } else { 7615 OS << getContext().getCUIDHash(); 7616 } 7617 } 7618 7619 void CodeGenModule::moveLazyEmissionStates(CodeGenModule *NewBuilder) { 7620 assert(DeferredDeclsToEmit.empty() && 7621 "Should have emitted all decls deferred to emit."); 7622 assert(NewBuilder->DeferredDecls.empty() && 7623 "Newly created module should not have deferred decls"); 7624 NewBuilder->DeferredDecls = std::move(DeferredDecls); 7625 assert(EmittedDeferredDecls.empty() && 7626 "Still have (unmerged) EmittedDeferredDecls deferred decls"); 7627 7628 assert(NewBuilder->DeferredVTables.empty() && 7629 "Newly created module should not have deferred vtables"); 7630 NewBuilder->DeferredVTables = std::move(DeferredVTables); 7631 7632 assert(NewBuilder->MangledDeclNames.empty() && 7633 "Newly created module should not have mangled decl names"); 7634 assert(NewBuilder->Manglings.empty() && 7635 "Newly created module should not have manglings"); 7636 NewBuilder->Manglings = std::move(Manglings); 7637 7638 NewBuilder->WeakRefReferences = std::move(WeakRefReferences); 7639 7640 NewBuilder->TBAA = std::move(TBAA); 7641 7642 NewBuilder->ABI->MangleCtx = std::move(ABI->MangleCtx); 7643 } 7644