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 if (CallingConv == llvm::CallingConv::X86_VectorCall && 2091 getTarget().getTriple().isWindowsArm64EC()) { 2092 SourceLocation Loc; 2093 if (const Decl *D = GD.getDecl()) 2094 Loc = D->getLocation(); 2095 2096 Error(Loc, "__vectorcall calling convention is not currently supported"); 2097 } 2098 F->setAttributes(PAL); 2099 F->setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv)); 2100 } 2101 2102 static void removeImageAccessQualifier(std::string& TyName) { 2103 std::string ReadOnlyQual("__read_only"); 2104 std::string::size_type ReadOnlyPos = TyName.find(ReadOnlyQual); 2105 if (ReadOnlyPos != std::string::npos) 2106 // "+ 1" for the space after access qualifier. 2107 TyName.erase(ReadOnlyPos, ReadOnlyQual.size() + 1); 2108 else { 2109 std::string WriteOnlyQual("__write_only"); 2110 std::string::size_type WriteOnlyPos = TyName.find(WriteOnlyQual); 2111 if (WriteOnlyPos != std::string::npos) 2112 TyName.erase(WriteOnlyPos, WriteOnlyQual.size() + 1); 2113 else { 2114 std::string ReadWriteQual("__read_write"); 2115 std::string::size_type ReadWritePos = TyName.find(ReadWriteQual); 2116 if (ReadWritePos != std::string::npos) 2117 TyName.erase(ReadWritePos, ReadWriteQual.size() + 1); 2118 } 2119 } 2120 } 2121 2122 // Returns the address space id that should be produced to the 2123 // kernel_arg_addr_space metadata. This is always fixed to the ids 2124 // as specified in the SPIR 2.0 specification in order to differentiate 2125 // for example in clGetKernelArgInfo() implementation between the address 2126 // spaces with targets without unique mapping to the OpenCL address spaces 2127 // (basically all single AS CPUs). 2128 static unsigned ArgInfoAddressSpace(LangAS AS) { 2129 switch (AS) { 2130 case LangAS::opencl_global: 2131 return 1; 2132 case LangAS::opencl_constant: 2133 return 2; 2134 case LangAS::opencl_local: 2135 return 3; 2136 case LangAS::opencl_generic: 2137 return 4; // Not in SPIR 2.0 specs. 2138 case LangAS::opencl_global_device: 2139 return 5; 2140 case LangAS::opencl_global_host: 2141 return 6; 2142 default: 2143 return 0; // Assume private. 2144 } 2145 } 2146 2147 void CodeGenModule::GenKernelArgMetadata(llvm::Function *Fn, 2148 const FunctionDecl *FD, 2149 CodeGenFunction *CGF) { 2150 assert(((FD && CGF) || (!FD && !CGF)) && 2151 "Incorrect use - FD and CGF should either be both null or not!"); 2152 // Create MDNodes that represent the kernel arg metadata. 2153 // Each MDNode is a list in the form of "key", N number of values which is 2154 // the same number of values as their are kernel arguments. 2155 2156 const PrintingPolicy &Policy = Context.getPrintingPolicy(); 2157 2158 // MDNode for the kernel argument address space qualifiers. 2159 SmallVector<llvm::Metadata *, 8> addressQuals; 2160 2161 // MDNode for the kernel argument access qualifiers (images only). 2162 SmallVector<llvm::Metadata *, 8> accessQuals; 2163 2164 // MDNode for the kernel argument type names. 2165 SmallVector<llvm::Metadata *, 8> argTypeNames; 2166 2167 // MDNode for the kernel argument base type names. 2168 SmallVector<llvm::Metadata *, 8> argBaseTypeNames; 2169 2170 // MDNode for the kernel argument type qualifiers. 2171 SmallVector<llvm::Metadata *, 8> argTypeQuals; 2172 2173 // MDNode for the kernel argument names. 2174 SmallVector<llvm::Metadata *, 8> argNames; 2175 2176 if (FD && CGF) 2177 for (unsigned i = 0, e = FD->getNumParams(); i != e; ++i) { 2178 const ParmVarDecl *parm = FD->getParamDecl(i); 2179 // Get argument name. 2180 argNames.push_back(llvm::MDString::get(VMContext, parm->getName())); 2181 2182 if (!getLangOpts().OpenCL) 2183 continue; 2184 QualType ty = parm->getType(); 2185 std::string typeQuals; 2186 2187 // Get image and pipe access qualifier: 2188 if (ty->isImageType() || ty->isPipeType()) { 2189 const Decl *PDecl = parm; 2190 if (const auto *TD = ty->getAs<TypedefType>()) 2191 PDecl = TD->getDecl(); 2192 const OpenCLAccessAttr *A = PDecl->getAttr<OpenCLAccessAttr>(); 2193 if (A && A->isWriteOnly()) 2194 accessQuals.push_back(llvm::MDString::get(VMContext, "write_only")); 2195 else if (A && A->isReadWrite()) 2196 accessQuals.push_back(llvm::MDString::get(VMContext, "read_write")); 2197 else 2198 accessQuals.push_back(llvm::MDString::get(VMContext, "read_only")); 2199 } else 2200 accessQuals.push_back(llvm::MDString::get(VMContext, "none")); 2201 2202 auto getTypeSpelling = [&](QualType Ty) { 2203 auto typeName = Ty.getUnqualifiedType().getAsString(Policy); 2204 2205 if (Ty.isCanonical()) { 2206 StringRef typeNameRef = typeName; 2207 // Turn "unsigned type" to "utype" 2208 if (typeNameRef.consume_front("unsigned ")) 2209 return std::string("u") + typeNameRef.str(); 2210 if (typeNameRef.consume_front("signed ")) 2211 return typeNameRef.str(); 2212 } 2213 2214 return typeName; 2215 }; 2216 2217 if (ty->isPointerType()) { 2218 QualType pointeeTy = ty->getPointeeType(); 2219 2220 // Get address qualifier. 2221 addressQuals.push_back( 2222 llvm::ConstantAsMetadata::get(CGF->Builder.getInt32( 2223 ArgInfoAddressSpace(pointeeTy.getAddressSpace())))); 2224 2225 // Get argument type name. 2226 std::string typeName = getTypeSpelling(pointeeTy) + "*"; 2227 std::string baseTypeName = 2228 getTypeSpelling(pointeeTy.getCanonicalType()) + "*"; 2229 argTypeNames.push_back(llvm::MDString::get(VMContext, typeName)); 2230 argBaseTypeNames.push_back( 2231 llvm::MDString::get(VMContext, baseTypeName)); 2232 2233 // Get argument type qualifiers: 2234 if (ty.isRestrictQualified()) 2235 typeQuals = "restrict"; 2236 if (pointeeTy.isConstQualified() || 2237 (pointeeTy.getAddressSpace() == LangAS::opencl_constant)) 2238 typeQuals += typeQuals.empty() ? "const" : " const"; 2239 if (pointeeTy.isVolatileQualified()) 2240 typeQuals += typeQuals.empty() ? "volatile" : " volatile"; 2241 } else { 2242 uint32_t AddrSpc = 0; 2243 bool isPipe = ty->isPipeType(); 2244 if (ty->isImageType() || isPipe) 2245 AddrSpc = ArgInfoAddressSpace(LangAS::opencl_global); 2246 2247 addressQuals.push_back( 2248 llvm::ConstantAsMetadata::get(CGF->Builder.getInt32(AddrSpc))); 2249 2250 // Get argument type name. 2251 ty = isPipe ? ty->castAs<PipeType>()->getElementType() : ty; 2252 std::string typeName = getTypeSpelling(ty); 2253 std::string baseTypeName = getTypeSpelling(ty.getCanonicalType()); 2254 2255 // Remove access qualifiers on images 2256 // (as they are inseparable from type in clang implementation, 2257 // but OpenCL spec provides a special query to get access qualifier 2258 // via clGetKernelArgInfo with CL_KERNEL_ARG_ACCESS_QUALIFIER): 2259 if (ty->isImageType()) { 2260 removeImageAccessQualifier(typeName); 2261 removeImageAccessQualifier(baseTypeName); 2262 } 2263 2264 argTypeNames.push_back(llvm::MDString::get(VMContext, typeName)); 2265 argBaseTypeNames.push_back( 2266 llvm::MDString::get(VMContext, baseTypeName)); 2267 2268 if (isPipe) 2269 typeQuals = "pipe"; 2270 } 2271 argTypeQuals.push_back(llvm::MDString::get(VMContext, typeQuals)); 2272 } 2273 2274 if (getLangOpts().OpenCL) { 2275 Fn->setMetadata("kernel_arg_addr_space", 2276 llvm::MDNode::get(VMContext, addressQuals)); 2277 Fn->setMetadata("kernel_arg_access_qual", 2278 llvm::MDNode::get(VMContext, accessQuals)); 2279 Fn->setMetadata("kernel_arg_type", 2280 llvm::MDNode::get(VMContext, argTypeNames)); 2281 Fn->setMetadata("kernel_arg_base_type", 2282 llvm::MDNode::get(VMContext, argBaseTypeNames)); 2283 Fn->setMetadata("kernel_arg_type_qual", 2284 llvm::MDNode::get(VMContext, argTypeQuals)); 2285 } 2286 if (getCodeGenOpts().EmitOpenCLArgMetadata || 2287 getCodeGenOpts().HIPSaveKernelArgName) 2288 Fn->setMetadata("kernel_arg_name", 2289 llvm::MDNode::get(VMContext, argNames)); 2290 } 2291 2292 /// Determines whether the language options require us to model 2293 /// unwind exceptions. We treat -fexceptions as mandating this 2294 /// except under the fragile ObjC ABI with only ObjC exceptions 2295 /// enabled. This means, for example, that C with -fexceptions 2296 /// enables this. 2297 static bool hasUnwindExceptions(const LangOptions &LangOpts) { 2298 // If exceptions are completely disabled, obviously this is false. 2299 if (!LangOpts.Exceptions) return false; 2300 2301 // If C++ exceptions are enabled, this is true. 2302 if (LangOpts.CXXExceptions) return true; 2303 2304 // If ObjC exceptions are enabled, this depends on the ABI. 2305 if (LangOpts.ObjCExceptions) { 2306 return LangOpts.ObjCRuntime.hasUnwindExceptions(); 2307 } 2308 2309 return true; 2310 } 2311 2312 static bool requiresMemberFunctionPointerTypeMetadata(CodeGenModule &CGM, 2313 const CXXMethodDecl *MD) { 2314 // Check that the type metadata can ever actually be used by a call. 2315 if (!CGM.getCodeGenOpts().LTOUnit || 2316 !CGM.HasHiddenLTOVisibility(MD->getParent())) 2317 return false; 2318 2319 // Only functions whose address can be taken with a member function pointer 2320 // need this sort of type metadata. 2321 return MD->isImplicitObjectMemberFunction() && !MD->isVirtual() && 2322 !isa<CXXConstructorDecl, CXXDestructorDecl>(MD); 2323 } 2324 2325 SmallVector<const CXXRecordDecl *, 0> 2326 CodeGenModule::getMostBaseClasses(const CXXRecordDecl *RD) { 2327 llvm::SetVector<const CXXRecordDecl *> MostBases; 2328 2329 std::function<void (const CXXRecordDecl *)> CollectMostBases; 2330 CollectMostBases = [&](const CXXRecordDecl *RD) { 2331 if (RD->getNumBases() == 0) 2332 MostBases.insert(RD); 2333 for (const CXXBaseSpecifier &B : RD->bases()) 2334 CollectMostBases(B.getType()->getAsCXXRecordDecl()); 2335 }; 2336 CollectMostBases(RD); 2337 return MostBases.takeVector(); 2338 } 2339 2340 void CodeGenModule::SetLLVMFunctionAttributesForDefinition(const Decl *D, 2341 llvm::Function *F) { 2342 llvm::AttrBuilder B(F->getContext()); 2343 2344 if ((!D || !D->hasAttr<NoUwtableAttr>()) && CodeGenOpts.UnwindTables) 2345 B.addUWTableAttr(llvm::UWTableKind(CodeGenOpts.UnwindTables)); 2346 2347 if (CodeGenOpts.StackClashProtector) 2348 B.addAttribute("probe-stack", "inline-asm"); 2349 2350 if (CodeGenOpts.StackProbeSize && CodeGenOpts.StackProbeSize != 4096) 2351 B.addAttribute("stack-probe-size", 2352 std::to_string(CodeGenOpts.StackProbeSize)); 2353 2354 if (!hasUnwindExceptions(LangOpts)) 2355 B.addAttribute(llvm::Attribute::NoUnwind); 2356 2357 if (D && D->hasAttr<NoStackProtectorAttr>()) 2358 ; // Do nothing. 2359 else if (D && D->hasAttr<StrictGuardStackCheckAttr>() && 2360 isStackProtectorOn(LangOpts, getTriple(), LangOptions::SSPOn)) 2361 B.addAttribute(llvm::Attribute::StackProtectStrong); 2362 else if (isStackProtectorOn(LangOpts, getTriple(), LangOptions::SSPOn)) 2363 B.addAttribute(llvm::Attribute::StackProtect); 2364 else if (isStackProtectorOn(LangOpts, getTriple(), LangOptions::SSPStrong)) 2365 B.addAttribute(llvm::Attribute::StackProtectStrong); 2366 else if (isStackProtectorOn(LangOpts, getTriple(), LangOptions::SSPReq)) 2367 B.addAttribute(llvm::Attribute::StackProtectReq); 2368 2369 if (!D) { 2370 // If we don't have a declaration to control inlining, the function isn't 2371 // explicitly marked as alwaysinline for semantic reasons, and inlining is 2372 // disabled, mark the function as noinline. 2373 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline) && 2374 CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining) 2375 B.addAttribute(llvm::Attribute::NoInline); 2376 2377 F->addFnAttrs(B); 2378 return; 2379 } 2380 2381 // Handle SME attributes that apply to function definitions, 2382 // rather than to function prototypes. 2383 if (D->hasAttr<ArmLocallyStreamingAttr>()) 2384 B.addAttribute("aarch64_pstate_sm_body"); 2385 2386 if (auto *Attr = D->getAttr<ArmNewAttr>()) { 2387 if (Attr->isNewZA()) 2388 B.addAttribute("aarch64_new_za"); 2389 if (Attr->isNewZT0()) 2390 B.addAttribute("aarch64_new_zt0"); 2391 } 2392 2393 // Track whether we need to add the optnone LLVM attribute, 2394 // starting with the default for this optimization level. 2395 bool ShouldAddOptNone = 2396 !CodeGenOpts.DisableO0ImplyOptNone && CodeGenOpts.OptimizationLevel == 0; 2397 // We can't add optnone in the following cases, it won't pass the verifier. 2398 ShouldAddOptNone &= !D->hasAttr<MinSizeAttr>(); 2399 ShouldAddOptNone &= !D->hasAttr<AlwaysInlineAttr>(); 2400 2401 // Add optnone, but do so only if the function isn't always_inline. 2402 if ((ShouldAddOptNone || D->hasAttr<OptimizeNoneAttr>()) && 2403 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) { 2404 B.addAttribute(llvm::Attribute::OptimizeNone); 2405 2406 // OptimizeNone implies noinline; we should not be inlining such functions. 2407 B.addAttribute(llvm::Attribute::NoInline); 2408 2409 // We still need to handle naked functions even though optnone subsumes 2410 // much of their semantics. 2411 if (D->hasAttr<NakedAttr>()) 2412 B.addAttribute(llvm::Attribute::Naked); 2413 2414 // OptimizeNone wins over OptimizeForSize and MinSize. 2415 F->removeFnAttr(llvm::Attribute::OptimizeForSize); 2416 F->removeFnAttr(llvm::Attribute::MinSize); 2417 } else if (D->hasAttr<NakedAttr>()) { 2418 // Naked implies noinline: we should not be inlining such functions. 2419 B.addAttribute(llvm::Attribute::Naked); 2420 B.addAttribute(llvm::Attribute::NoInline); 2421 } else if (D->hasAttr<NoDuplicateAttr>()) { 2422 B.addAttribute(llvm::Attribute::NoDuplicate); 2423 } else if (D->hasAttr<NoInlineAttr>() && !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) { 2424 // Add noinline if the function isn't always_inline. 2425 B.addAttribute(llvm::Attribute::NoInline); 2426 } else if (D->hasAttr<AlwaysInlineAttr>() && 2427 !F->hasFnAttribute(llvm::Attribute::NoInline)) { 2428 // (noinline wins over always_inline, and we can't specify both in IR) 2429 B.addAttribute(llvm::Attribute::AlwaysInline); 2430 } else if (CodeGenOpts.getInlining() == CodeGenOptions::OnlyAlwaysInlining) { 2431 // If we're not inlining, then force everything that isn't always_inline to 2432 // carry an explicit noinline attribute. 2433 if (!F->hasFnAttribute(llvm::Attribute::AlwaysInline)) 2434 B.addAttribute(llvm::Attribute::NoInline); 2435 } else { 2436 // Otherwise, propagate the inline hint attribute and potentially use its 2437 // absence to mark things as noinline. 2438 if (auto *FD = dyn_cast<FunctionDecl>(D)) { 2439 // Search function and template pattern redeclarations for inline. 2440 auto CheckForInline = [](const FunctionDecl *FD) { 2441 auto CheckRedeclForInline = [](const FunctionDecl *Redecl) { 2442 return Redecl->isInlineSpecified(); 2443 }; 2444 if (any_of(FD->redecls(), CheckRedeclForInline)) 2445 return true; 2446 const FunctionDecl *Pattern = FD->getTemplateInstantiationPattern(); 2447 if (!Pattern) 2448 return false; 2449 return any_of(Pattern->redecls(), CheckRedeclForInline); 2450 }; 2451 if (CheckForInline(FD)) { 2452 B.addAttribute(llvm::Attribute::InlineHint); 2453 } else if (CodeGenOpts.getInlining() == 2454 CodeGenOptions::OnlyHintInlining && 2455 !FD->isInlined() && 2456 !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) { 2457 B.addAttribute(llvm::Attribute::NoInline); 2458 } 2459 } 2460 } 2461 2462 // Add other optimization related attributes if we are optimizing this 2463 // function. 2464 if (!D->hasAttr<OptimizeNoneAttr>()) { 2465 if (D->hasAttr<ColdAttr>()) { 2466 if (!ShouldAddOptNone) 2467 B.addAttribute(llvm::Attribute::OptimizeForSize); 2468 B.addAttribute(llvm::Attribute::Cold); 2469 } 2470 if (D->hasAttr<HotAttr>()) 2471 B.addAttribute(llvm::Attribute::Hot); 2472 if (D->hasAttr<MinSizeAttr>()) 2473 B.addAttribute(llvm::Attribute::MinSize); 2474 } 2475 2476 F->addFnAttrs(B); 2477 2478 unsigned alignment = D->getMaxAlignment() / Context.getCharWidth(); 2479 if (alignment) 2480 F->setAlignment(llvm::Align(alignment)); 2481 2482 if (!D->hasAttr<AlignedAttr>()) 2483 if (LangOpts.FunctionAlignment) 2484 F->setAlignment(llvm::Align(1ull << LangOpts.FunctionAlignment)); 2485 2486 // Some C++ ABIs require 2-byte alignment for member functions, in order to 2487 // reserve a bit for differentiating between virtual and non-virtual member 2488 // functions. If the current target's C++ ABI requires this and this is a 2489 // member function, set its alignment accordingly. 2490 if (getTarget().getCXXABI().areMemberFunctionsAligned()) { 2491 if (isa<CXXMethodDecl>(D) && F->getPointerAlignment(getDataLayout()) < 2) 2492 F->setAlignment(std::max(llvm::Align(2), F->getAlign().valueOrOne())); 2493 } 2494 2495 // In the cross-dso CFI mode with canonical jump tables, we want !type 2496 // attributes on definitions only. 2497 if (CodeGenOpts.SanitizeCfiCrossDso && 2498 CodeGenOpts.SanitizeCfiCanonicalJumpTables) { 2499 if (auto *FD = dyn_cast<FunctionDecl>(D)) { 2500 // Skip available_externally functions. They won't be codegen'ed in the 2501 // current module anyway. 2502 if (getContext().GetGVALinkageForFunction(FD) != GVA_AvailableExternally) 2503 CreateFunctionTypeMetadataForIcall(FD, F); 2504 } 2505 } 2506 2507 // Emit type metadata on member functions for member function pointer checks. 2508 // These are only ever necessary on definitions; we're guaranteed that the 2509 // definition will be present in the LTO unit as a result of LTO visibility. 2510 auto *MD = dyn_cast<CXXMethodDecl>(D); 2511 if (MD && requiresMemberFunctionPointerTypeMetadata(*this, MD)) { 2512 for (const CXXRecordDecl *Base : getMostBaseClasses(MD->getParent())) { 2513 llvm::Metadata *Id = 2514 CreateMetadataIdentifierForType(Context.getMemberPointerType( 2515 MD->getType(), Context.getRecordType(Base).getTypePtr())); 2516 F->addTypeMetadata(0, Id); 2517 } 2518 } 2519 } 2520 2521 void CodeGenModule::SetCommonAttributes(GlobalDecl GD, llvm::GlobalValue *GV) { 2522 const Decl *D = GD.getDecl(); 2523 if (isa_and_nonnull<NamedDecl>(D)) 2524 setGVProperties(GV, GD); 2525 else 2526 GV->setVisibility(llvm::GlobalValue::DefaultVisibility); 2527 2528 if (D && D->hasAttr<UsedAttr>()) 2529 addUsedOrCompilerUsedGlobal(GV); 2530 2531 if (const auto *VD = dyn_cast_if_present<VarDecl>(D); 2532 VD && 2533 ((CodeGenOpts.KeepPersistentStorageVariables && 2534 (VD->getStorageDuration() == SD_Static || 2535 VD->getStorageDuration() == SD_Thread)) || 2536 (CodeGenOpts.KeepStaticConsts && VD->getStorageDuration() == SD_Static && 2537 VD->getType().isConstQualified()))) 2538 addUsedOrCompilerUsedGlobal(GV); 2539 } 2540 2541 bool CodeGenModule::GetCPUAndFeaturesAttributes(GlobalDecl GD, 2542 llvm::AttrBuilder &Attrs, 2543 bool SetTargetFeatures) { 2544 // Add target-cpu and target-features attributes to functions. If 2545 // we have a decl for the function and it has a target attribute then 2546 // parse that and add it to the feature set. 2547 StringRef TargetCPU = getTarget().getTargetOpts().CPU; 2548 StringRef TuneCPU = getTarget().getTargetOpts().TuneCPU; 2549 std::vector<std::string> Features; 2550 const auto *FD = dyn_cast_or_null<FunctionDecl>(GD.getDecl()); 2551 FD = FD ? FD->getMostRecentDecl() : FD; 2552 const auto *TD = FD ? FD->getAttr<TargetAttr>() : nullptr; 2553 const auto *TV = FD ? FD->getAttr<TargetVersionAttr>() : nullptr; 2554 assert((!TD || !TV) && "both target_version and target specified"); 2555 const auto *SD = FD ? FD->getAttr<CPUSpecificAttr>() : nullptr; 2556 const auto *TC = FD ? FD->getAttr<TargetClonesAttr>() : nullptr; 2557 bool AddedAttr = false; 2558 if (TD || TV || SD || TC) { 2559 llvm::StringMap<bool> FeatureMap; 2560 getContext().getFunctionFeatureMap(FeatureMap, GD); 2561 2562 // Produce the canonical string for this set of features. 2563 for (const llvm::StringMap<bool>::value_type &Entry : FeatureMap) 2564 Features.push_back((Entry.getValue() ? "+" : "-") + Entry.getKey().str()); 2565 2566 // Now add the target-cpu and target-features to the function. 2567 // While we populated the feature map above, we still need to 2568 // get and parse the target attribute so we can get the cpu for 2569 // the function. 2570 if (TD) { 2571 ParsedTargetAttr ParsedAttr = 2572 Target.parseTargetAttr(TD->getFeaturesStr()); 2573 if (!ParsedAttr.CPU.empty() && 2574 getTarget().isValidCPUName(ParsedAttr.CPU)) { 2575 TargetCPU = ParsedAttr.CPU; 2576 TuneCPU = ""; // Clear the tune CPU. 2577 } 2578 if (!ParsedAttr.Tune.empty() && 2579 getTarget().isValidCPUName(ParsedAttr.Tune)) 2580 TuneCPU = ParsedAttr.Tune; 2581 } 2582 2583 if (SD) { 2584 // Apply the given CPU name as the 'tune-cpu' so that the optimizer can 2585 // favor this processor. 2586 TuneCPU = SD->getCPUName(GD.getMultiVersionIndex())->getName(); 2587 } 2588 } else { 2589 // Otherwise just add the existing target cpu and target features to the 2590 // function. 2591 Features = getTarget().getTargetOpts().Features; 2592 } 2593 2594 if (!TargetCPU.empty()) { 2595 Attrs.addAttribute("target-cpu", TargetCPU); 2596 AddedAttr = true; 2597 } 2598 if (!TuneCPU.empty()) { 2599 Attrs.addAttribute("tune-cpu", TuneCPU); 2600 AddedAttr = true; 2601 } 2602 if (!Features.empty() && SetTargetFeatures) { 2603 llvm::erase_if(Features, [&](const std::string& F) { 2604 return getTarget().isReadOnlyFeature(F.substr(1)); 2605 }); 2606 llvm::sort(Features); 2607 Attrs.addAttribute("target-features", llvm::join(Features, ",")); 2608 AddedAttr = true; 2609 } 2610 2611 return AddedAttr; 2612 } 2613 2614 void CodeGenModule::setNonAliasAttributes(GlobalDecl GD, 2615 llvm::GlobalObject *GO) { 2616 const Decl *D = GD.getDecl(); 2617 SetCommonAttributes(GD, GO); 2618 2619 if (D) { 2620 if (auto *GV = dyn_cast<llvm::GlobalVariable>(GO)) { 2621 if (D->hasAttr<RetainAttr>()) 2622 addUsedGlobal(GV); 2623 if (auto *SA = D->getAttr<PragmaClangBSSSectionAttr>()) 2624 GV->addAttribute("bss-section", SA->getName()); 2625 if (auto *SA = D->getAttr<PragmaClangDataSectionAttr>()) 2626 GV->addAttribute("data-section", SA->getName()); 2627 if (auto *SA = D->getAttr<PragmaClangRodataSectionAttr>()) 2628 GV->addAttribute("rodata-section", SA->getName()); 2629 if (auto *SA = D->getAttr<PragmaClangRelroSectionAttr>()) 2630 GV->addAttribute("relro-section", SA->getName()); 2631 } 2632 2633 if (auto *F = dyn_cast<llvm::Function>(GO)) { 2634 if (D->hasAttr<RetainAttr>()) 2635 addUsedGlobal(F); 2636 if (auto *SA = D->getAttr<PragmaClangTextSectionAttr>()) 2637 if (!D->getAttr<SectionAttr>()) 2638 F->setSection(SA->getName()); 2639 2640 llvm::AttrBuilder Attrs(F->getContext()); 2641 if (GetCPUAndFeaturesAttributes(GD, Attrs)) { 2642 // We know that GetCPUAndFeaturesAttributes will always have the 2643 // newest set, since it has the newest possible FunctionDecl, so the 2644 // new ones should replace the old. 2645 llvm::AttributeMask RemoveAttrs; 2646 RemoveAttrs.addAttribute("target-cpu"); 2647 RemoveAttrs.addAttribute("target-features"); 2648 RemoveAttrs.addAttribute("tune-cpu"); 2649 F->removeFnAttrs(RemoveAttrs); 2650 F->addFnAttrs(Attrs); 2651 } 2652 } 2653 2654 if (const auto *CSA = D->getAttr<CodeSegAttr>()) 2655 GO->setSection(CSA->getName()); 2656 else if (const auto *SA = D->getAttr<SectionAttr>()) 2657 GO->setSection(SA->getName()); 2658 } 2659 2660 getTargetCodeGenInfo().setTargetAttributes(D, GO, *this); 2661 } 2662 2663 void CodeGenModule::SetInternalFunctionAttributes(GlobalDecl GD, 2664 llvm::Function *F, 2665 const CGFunctionInfo &FI) { 2666 const Decl *D = GD.getDecl(); 2667 SetLLVMFunctionAttributes(GD, FI, F, /*IsThunk=*/false); 2668 SetLLVMFunctionAttributesForDefinition(D, F); 2669 2670 F->setLinkage(llvm::Function::InternalLinkage); 2671 2672 setNonAliasAttributes(GD, F); 2673 } 2674 2675 static void setLinkageForGV(llvm::GlobalValue *GV, const NamedDecl *ND) { 2676 // Set linkage and visibility in case we never see a definition. 2677 LinkageInfo LV = ND->getLinkageAndVisibility(); 2678 // Don't set internal linkage on declarations. 2679 // "extern_weak" is overloaded in LLVM; we probably should have 2680 // separate linkage types for this. 2681 if (isExternallyVisible(LV.getLinkage()) && 2682 (ND->hasAttr<WeakAttr>() || ND->isWeakImported())) 2683 GV->setLinkage(llvm::GlobalValue::ExternalWeakLinkage); 2684 } 2685 2686 void CodeGenModule::CreateFunctionTypeMetadataForIcall(const FunctionDecl *FD, 2687 llvm::Function *F) { 2688 // Only if we are checking indirect calls. 2689 if (!LangOpts.Sanitize.has(SanitizerKind::CFIICall)) 2690 return; 2691 2692 // Non-static class methods are handled via vtable or member function pointer 2693 // checks elsewhere. 2694 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 2695 return; 2696 2697 llvm::Metadata *MD = CreateMetadataIdentifierForType(FD->getType()); 2698 F->addTypeMetadata(0, MD); 2699 F->addTypeMetadata(0, CreateMetadataIdentifierGeneralized(FD->getType())); 2700 2701 // Emit a hash-based bit set entry for cross-DSO calls. 2702 if (CodeGenOpts.SanitizeCfiCrossDso) 2703 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD)) 2704 F->addTypeMetadata(0, llvm::ConstantAsMetadata::get(CrossDsoTypeId)); 2705 } 2706 2707 void CodeGenModule::setKCFIType(const FunctionDecl *FD, llvm::Function *F) { 2708 llvm::LLVMContext &Ctx = F->getContext(); 2709 llvm::MDBuilder MDB(Ctx); 2710 F->setMetadata(llvm::LLVMContext::MD_kcfi_type, 2711 llvm::MDNode::get( 2712 Ctx, MDB.createConstant(CreateKCFITypeId(FD->getType())))); 2713 } 2714 2715 static bool allowKCFIIdentifier(StringRef Name) { 2716 // KCFI type identifier constants are only necessary for external assembly 2717 // functions, which means it's safe to skip unusual names. Subset of 2718 // MCAsmInfo::isAcceptableChar() and MCAsmInfoXCOFF::isAcceptableChar(). 2719 return llvm::all_of(Name, [](const char &C) { 2720 return llvm::isAlnum(C) || C == '_' || C == '.'; 2721 }); 2722 } 2723 2724 void CodeGenModule::finalizeKCFITypes() { 2725 llvm::Module &M = getModule(); 2726 for (auto &F : M.functions()) { 2727 // Remove KCFI type metadata from non-address-taken local functions. 2728 bool AddressTaken = F.hasAddressTaken(); 2729 if (!AddressTaken && F.hasLocalLinkage()) 2730 F.eraseMetadata(llvm::LLVMContext::MD_kcfi_type); 2731 2732 // Generate a constant with the expected KCFI type identifier for all 2733 // address-taken function declarations to support annotating indirectly 2734 // called assembly functions. 2735 if (!AddressTaken || !F.isDeclaration()) 2736 continue; 2737 2738 const llvm::ConstantInt *Type; 2739 if (const llvm::MDNode *MD = F.getMetadata(llvm::LLVMContext::MD_kcfi_type)) 2740 Type = llvm::mdconst::extract<llvm::ConstantInt>(MD->getOperand(0)); 2741 else 2742 continue; 2743 2744 StringRef Name = F.getName(); 2745 if (!allowKCFIIdentifier(Name)) 2746 continue; 2747 2748 std::string Asm = (".weak __kcfi_typeid_" + Name + "\n.set __kcfi_typeid_" + 2749 Name + ", " + Twine(Type->getZExtValue()) + "\n") 2750 .str(); 2751 M.appendModuleInlineAsm(Asm); 2752 } 2753 } 2754 2755 void CodeGenModule::SetFunctionAttributes(GlobalDecl GD, llvm::Function *F, 2756 bool IsIncompleteFunction, 2757 bool IsThunk) { 2758 2759 if (llvm::Intrinsic::ID IID = F->getIntrinsicID()) { 2760 // If this is an intrinsic function, set the function's attributes 2761 // to the intrinsic's attributes. 2762 F->setAttributes(llvm::Intrinsic::getAttributes(getLLVMContext(), IID)); 2763 return; 2764 } 2765 2766 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 2767 2768 if (!IsIncompleteFunction) 2769 SetLLVMFunctionAttributes(GD, getTypes().arrangeGlobalDeclaration(GD), F, 2770 IsThunk); 2771 2772 // Add the Returned attribute for "this", except for iOS 5 and earlier 2773 // where substantial code, including the libstdc++ dylib, was compiled with 2774 // GCC and does not actually return "this". 2775 if (!IsThunk && getCXXABI().HasThisReturn(GD) && 2776 !(getTriple().isiOS() && getTriple().isOSVersionLT(6))) { 2777 assert(!F->arg_empty() && 2778 F->arg_begin()->getType() 2779 ->canLosslesslyBitCastTo(F->getReturnType()) && 2780 "unexpected this return"); 2781 F->addParamAttr(0, llvm::Attribute::Returned); 2782 } 2783 2784 // Only a few attributes are set on declarations; these may later be 2785 // overridden by a definition. 2786 2787 setLinkageForGV(F, FD); 2788 setGVProperties(F, FD); 2789 2790 // Setup target-specific attributes. 2791 if (!IsIncompleteFunction && F->isDeclaration()) 2792 getTargetCodeGenInfo().setTargetAttributes(FD, F, *this); 2793 2794 if (const auto *CSA = FD->getAttr<CodeSegAttr>()) 2795 F->setSection(CSA->getName()); 2796 else if (const auto *SA = FD->getAttr<SectionAttr>()) 2797 F->setSection(SA->getName()); 2798 2799 if (const auto *EA = FD->getAttr<ErrorAttr>()) { 2800 if (EA->isError()) 2801 F->addFnAttr("dontcall-error", EA->getUserDiagnostic()); 2802 else if (EA->isWarning()) 2803 F->addFnAttr("dontcall-warn", EA->getUserDiagnostic()); 2804 } 2805 2806 // If we plan on emitting this inline builtin, we can't treat it as a builtin. 2807 if (FD->isInlineBuiltinDeclaration()) { 2808 const FunctionDecl *FDBody; 2809 bool HasBody = FD->hasBody(FDBody); 2810 (void)HasBody; 2811 assert(HasBody && "Inline builtin declarations should always have an " 2812 "available body!"); 2813 if (shouldEmitFunction(FDBody)) 2814 F->addFnAttr(llvm::Attribute::NoBuiltin); 2815 } 2816 2817 if (FD->isReplaceableGlobalAllocationFunction()) { 2818 // A replaceable global allocation function does not act like a builtin by 2819 // default, only if it is invoked by a new-expression or delete-expression. 2820 F->addFnAttr(llvm::Attribute::NoBuiltin); 2821 } 2822 2823 if (isa<CXXConstructorDecl>(FD) || isa<CXXDestructorDecl>(FD)) 2824 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 2825 else if (const auto *MD = dyn_cast<CXXMethodDecl>(FD)) 2826 if (MD->isVirtual()) 2827 F->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 2828 2829 // Don't emit entries for function declarations in the cross-DSO mode. This 2830 // is handled with better precision by the receiving DSO. But if jump tables 2831 // are non-canonical then we need type metadata in order to produce the local 2832 // jump table. 2833 if (!CodeGenOpts.SanitizeCfiCrossDso || 2834 !CodeGenOpts.SanitizeCfiCanonicalJumpTables) 2835 CreateFunctionTypeMetadataForIcall(FD, F); 2836 2837 if (LangOpts.Sanitize.has(SanitizerKind::KCFI)) 2838 setKCFIType(FD, F); 2839 2840 if (getLangOpts().OpenMP && FD->hasAttr<OMPDeclareSimdDeclAttr>()) 2841 getOpenMPRuntime().emitDeclareSimdFunction(FD, F); 2842 2843 if (CodeGenOpts.InlineMaxStackSize != UINT_MAX) 2844 F->addFnAttr("inline-max-stacksize", llvm::utostr(CodeGenOpts.InlineMaxStackSize)); 2845 2846 if (const auto *CB = FD->getAttr<CallbackAttr>()) { 2847 // Annotate the callback behavior as metadata: 2848 // - The callback callee (as argument number). 2849 // - The callback payloads (as argument numbers). 2850 llvm::LLVMContext &Ctx = F->getContext(); 2851 llvm::MDBuilder MDB(Ctx); 2852 2853 // The payload indices are all but the first one in the encoding. The first 2854 // identifies the callback callee. 2855 int CalleeIdx = *CB->encoding_begin(); 2856 ArrayRef<int> PayloadIndices(CB->encoding_begin() + 1, CB->encoding_end()); 2857 F->addMetadata(llvm::LLVMContext::MD_callback, 2858 *llvm::MDNode::get(Ctx, {MDB.createCallbackEncoding( 2859 CalleeIdx, PayloadIndices, 2860 /* VarArgsArePassed */ false)})); 2861 } 2862 } 2863 2864 void CodeGenModule::addUsedGlobal(llvm::GlobalValue *GV) { 2865 assert((isa<llvm::Function>(GV) || !GV->isDeclaration()) && 2866 "Only globals with definition can force usage."); 2867 LLVMUsed.emplace_back(GV); 2868 } 2869 2870 void CodeGenModule::addCompilerUsedGlobal(llvm::GlobalValue *GV) { 2871 assert(!GV->isDeclaration() && 2872 "Only globals with definition can force usage."); 2873 LLVMCompilerUsed.emplace_back(GV); 2874 } 2875 2876 void CodeGenModule::addUsedOrCompilerUsedGlobal(llvm::GlobalValue *GV) { 2877 assert((isa<llvm::Function>(GV) || !GV->isDeclaration()) && 2878 "Only globals with definition can force usage."); 2879 if (getTriple().isOSBinFormatELF()) 2880 LLVMCompilerUsed.emplace_back(GV); 2881 else 2882 LLVMUsed.emplace_back(GV); 2883 } 2884 2885 static void emitUsed(CodeGenModule &CGM, StringRef Name, 2886 std::vector<llvm::WeakTrackingVH> &List) { 2887 // Don't create llvm.used if there is no need. 2888 if (List.empty()) 2889 return; 2890 2891 // Convert List to what ConstantArray needs. 2892 SmallVector<llvm::Constant*, 8> UsedArray; 2893 UsedArray.resize(List.size()); 2894 for (unsigned i = 0, e = List.size(); i != e; ++i) { 2895 UsedArray[i] = 2896 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast( 2897 cast<llvm::Constant>(&*List[i]), CGM.Int8PtrTy); 2898 } 2899 2900 if (UsedArray.empty()) 2901 return; 2902 llvm::ArrayType *ATy = llvm::ArrayType::get(CGM.Int8PtrTy, UsedArray.size()); 2903 2904 auto *GV = new llvm::GlobalVariable( 2905 CGM.getModule(), ATy, false, llvm::GlobalValue::AppendingLinkage, 2906 llvm::ConstantArray::get(ATy, UsedArray), Name); 2907 2908 GV->setSection("llvm.metadata"); 2909 } 2910 2911 void CodeGenModule::emitLLVMUsed() { 2912 emitUsed(*this, "llvm.used", LLVMUsed); 2913 emitUsed(*this, "llvm.compiler.used", LLVMCompilerUsed); 2914 } 2915 2916 void CodeGenModule::AppendLinkerOptions(StringRef Opts) { 2917 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opts); 2918 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts)); 2919 } 2920 2921 void CodeGenModule::AddDetectMismatch(StringRef Name, StringRef Value) { 2922 llvm::SmallString<32> Opt; 2923 getTargetCodeGenInfo().getDetectMismatchOption(Name, Value, Opt); 2924 if (Opt.empty()) 2925 return; 2926 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt); 2927 LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts)); 2928 } 2929 2930 void CodeGenModule::AddDependentLib(StringRef Lib) { 2931 auto &C = getLLVMContext(); 2932 if (getTarget().getTriple().isOSBinFormatELF()) { 2933 ELFDependentLibraries.push_back( 2934 llvm::MDNode::get(C, llvm::MDString::get(C, Lib))); 2935 return; 2936 } 2937 2938 llvm::SmallString<24> Opt; 2939 getTargetCodeGenInfo().getDependentLibraryOption(Lib, Opt); 2940 auto *MDOpts = llvm::MDString::get(getLLVMContext(), Opt); 2941 LinkerOptionsMetadata.push_back(llvm::MDNode::get(C, MDOpts)); 2942 } 2943 2944 /// Add link options implied by the given module, including modules 2945 /// it depends on, using a postorder walk. 2946 static void addLinkOptionsPostorder(CodeGenModule &CGM, Module *Mod, 2947 SmallVectorImpl<llvm::MDNode *> &Metadata, 2948 llvm::SmallPtrSet<Module *, 16> &Visited) { 2949 // Import this module's parent. 2950 if (Mod->Parent && Visited.insert(Mod->Parent).second) { 2951 addLinkOptionsPostorder(CGM, Mod->Parent, Metadata, Visited); 2952 } 2953 2954 // Import this module's dependencies. 2955 for (Module *Import : llvm::reverse(Mod->Imports)) { 2956 if (Visited.insert(Import).second) 2957 addLinkOptionsPostorder(CGM, Import, Metadata, Visited); 2958 } 2959 2960 // Add linker options to link against the libraries/frameworks 2961 // described by this module. 2962 llvm::LLVMContext &Context = CGM.getLLVMContext(); 2963 bool IsELF = CGM.getTarget().getTriple().isOSBinFormatELF(); 2964 2965 // For modules that use export_as for linking, use that module 2966 // name instead. 2967 if (Mod->UseExportAsModuleLinkName) 2968 return; 2969 2970 for (const Module::LinkLibrary &LL : llvm::reverse(Mod->LinkLibraries)) { 2971 // Link against a framework. Frameworks are currently Darwin only, so we 2972 // don't to ask TargetCodeGenInfo for the spelling of the linker option. 2973 if (LL.IsFramework) { 2974 llvm::Metadata *Args[2] = {llvm::MDString::get(Context, "-framework"), 2975 llvm::MDString::get(Context, LL.Library)}; 2976 2977 Metadata.push_back(llvm::MDNode::get(Context, Args)); 2978 continue; 2979 } 2980 2981 // Link against a library. 2982 if (IsELF) { 2983 llvm::Metadata *Args[2] = { 2984 llvm::MDString::get(Context, "lib"), 2985 llvm::MDString::get(Context, LL.Library), 2986 }; 2987 Metadata.push_back(llvm::MDNode::get(Context, Args)); 2988 } else { 2989 llvm::SmallString<24> Opt; 2990 CGM.getTargetCodeGenInfo().getDependentLibraryOption(LL.Library, Opt); 2991 auto *OptString = llvm::MDString::get(Context, Opt); 2992 Metadata.push_back(llvm::MDNode::get(Context, OptString)); 2993 } 2994 } 2995 } 2996 2997 void CodeGenModule::EmitModuleInitializers(clang::Module *Primary) { 2998 assert(Primary->isNamedModuleUnit() && 2999 "We should only emit module initializers for named modules."); 3000 3001 // Emit the initializers in the order that sub-modules appear in the 3002 // source, first Global Module Fragments, if present. 3003 if (auto GMF = Primary->getGlobalModuleFragment()) { 3004 for (Decl *D : getContext().getModuleInitializers(GMF)) { 3005 if (isa<ImportDecl>(D)) 3006 continue; 3007 assert(isa<VarDecl>(D) && "GMF initializer decl is not a var?"); 3008 EmitTopLevelDecl(D); 3009 } 3010 } 3011 // Second any associated with the module, itself. 3012 for (Decl *D : getContext().getModuleInitializers(Primary)) { 3013 // Skip import decls, the inits for those are called explicitly. 3014 if (isa<ImportDecl>(D)) 3015 continue; 3016 EmitTopLevelDecl(D); 3017 } 3018 // Third any associated with the Privat eMOdule Fragment, if present. 3019 if (auto PMF = Primary->getPrivateModuleFragment()) { 3020 for (Decl *D : getContext().getModuleInitializers(PMF)) { 3021 // Skip import decls, the inits for those are called explicitly. 3022 if (isa<ImportDecl>(D)) 3023 continue; 3024 assert(isa<VarDecl>(D) && "PMF initializer decl is not a var?"); 3025 EmitTopLevelDecl(D); 3026 } 3027 } 3028 } 3029 3030 void CodeGenModule::EmitModuleLinkOptions() { 3031 // Collect the set of all of the modules we want to visit to emit link 3032 // options, which is essentially the imported modules and all of their 3033 // non-explicit child modules. 3034 llvm::SetVector<clang::Module *> LinkModules; 3035 llvm::SmallPtrSet<clang::Module *, 16> Visited; 3036 SmallVector<clang::Module *, 16> Stack; 3037 3038 // Seed the stack with imported modules. 3039 for (Module *M : ImportedModules) { 3040 // Do not add any link flags when an implementation TU of a module imports 3041 // a header of that same module. 3042 if (M->getTopLevelModuleName() == getLangOpts().CurrentModule && 3043 !getLangOpts().isCompilingModule()) 3044 continue; 3045 if (Visited.insert(M).second) 3046 Stack.push_back(M); 3047 } 3048 3049 // Find all of the modules to import, making a little effort to prune 3050 // non-leaf modules. 3051 while (!Stack.empty()) { 3052 clang::Module *Mod = Stack.pop_back_val(); 3053 3054 bool AnyChildren = false; 3055 3056 // Visit the submodules of this module. 3057 for (const auto &SM : Mod->submodules()) { 3058 // Skip explicit children; they need to be explicitly imported to be 3059 // linked against. 3060 if (SM->IsExplicit) 3061 continue; 3062 3063 if (Visited.insert(SM).second) { 3064 Stack.push_back(SM); 3065 AnyChildren = true; 3066 } 3067 } 3068 3069 // We didn't find any children, so add this module to the list of 3070 // modules to link against. 3071 if (!AnyChildren) { 3072 LinkModules.insert(Mod); 3073 } 3074 } 3075 3076 // Add link options for all of the imported modules in reverse topological 3077 // order. We don't do anything to try to order import link flags with respect 3078 // to linker options inserted by things like #pragma comment(). 3079 SmallVector<llvm::MDNode *, 16> MetadataArgs; 3080 Visited.clear(); 3081 for (Module *M : LinkModules) 3082 if (Visited.insert(M).second) 3083 addLinkOptionsPostorder(*this, M, MetadataArgs, Visited); 3084 std::reverse(MetadataArgs.begin(), MetadataArgs.end()); 3085 LinkerOptionsMetadata.append(MetadataArgs.begin(), MetadataArgs.end()); 3086 3087 // Add the linker options metadata flag. 3088 auto *NMD = getModule().getOrInsertNamedMetadata("llvm.linker.options"); 3089 for (auto *MD : LinkerOptionsMetadata) 3090 NMD->addOperand(MD); 3091 } 3092 3093 void CodeGenModule::EmitDeferred() { 3094 // Emit deferred declare target declarations. 3095 if (getLangOpts().OpenMP && !getLangOpts().OpenMPSimd) 3096 getOpenMPRuntime().emitDeferredTargetDecls(); 3097 3098 // Emit code for any potentially referenced deferred decls. Since a 3099 // previously unused static decl may become used during the generation of code 3100 // for a static function, iterate until no changes are made. 3101 3102 if (!DeferredVTables.empty()) { 3103 EmitDeferredVTables(); 3104 3105 // Emitting a vtable doesn't directly cause more vtables to 3106 // become deferred, although it can cause functions to be 3107 // emitted that then need those vtables. 3108 assert(DeferredVTables.empty()); 3109 } 3110 3111 // Emit CUDA/HIP static device variables referenced by host code only. 3112 // Note we should not clear CUDADeviceVarODRUsedByHost since it is still 3113 // needed for further handling. 3114 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) 3115 llvm::append_range(DeferredDeclsToEmit, 3116 getContext().CUDADeviceVarODRUsedByHost); 3117 3118 // Stop if we're out of both deferred vtables and deferred declarations. 3119 if (DeferredDeclsToEmit.empty()) 3120 return; 3121 3122 // Grab the list of decls to emit. If EmitGlobalDefinition schedules more 3123 // work, it will not interfere with this. 3124 std::vector<GlobalDecl> CurDeclsToEmit; 3125 CurDeclsToEmit.swap(DeferredDeclsToEmit); 3126 3127 for (GlobalDecl &D : CurDeclsToEmit) { 3128 // We should call GetAddrOfGlobal with IsForDefinition set to true in order 3129 // to get GlobalValue with exactly the type we need, not something that 3130 // might had been created for another decl with the same mangled name but 3131 // different type. 3132 llvm::GlobalValue *GV = dyn_cast<llvm::GlobalValue>( 3133 GetAddrOfGlobal(D, ForDefinition)); 3134 3135 // In case of different address spaces, we may still get a cast, even with 3136 // IsForDefinition equal to true. Query mangled names table to get 3137 // GlobalValue. 3138 if (!GV) 3139 GV = GetGlobalValue(getMangledName(D)); 3140 3141 // Make sure GetGlobalValue returned non-null. 3142 assert(GV); 3143 3144 // Check to see if we've already emitted this. This is necessary 3145 // for a couple of reasons: first, decls can end up in the 3146 // deferred-decls queue multiple times, and second, decls can end 3147 // up with definitions in unusual ways (e.g. by an extern inline 3148 // function acquiring a strong function redefinition). Just 3149 // ignore these cases. 3150 if (!GV->isDeclaration()) 3151 continue; 3152 3153 // If this is OpenMP, check if it is legal to emit this global normally. 3154 if (LangOpts.OpenMP && OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(D)) 3155 continue; 3156 3157 // Otherwise, emit the definition and move on to the next one. 3158 EmitGlobalDefinition(D, GV); 3159 3160 // If we found out that we need to emit more decls, do that recursively. 3161 // This has the advantage that the decls are emitted in a DFS and related 3162 // ones are close together, which is convenient for testing. 3163 if (!DeferredVTables.empty() || !DeferredDeclsToEmit.empty()) { 3164 EmitDeferred(); 3165 assert(DeferredVTables.empty() && DeferredDeclsToEmit.empty()); 3166 } 3167 } 3168 } 3169 3170 void CodeGenModule::EmitVTablesOpportunistically() { 3171 // Try to emit external vtables as available_externally if they have emitted 3172 // all inlined virtual functions. It runs after EmitDeferred() and therefore 3173 // is not allowed to create new references to things that need to be emitted 3174 // lazily. Note that it also uses fact that we eagerly emitting RTTI. 3175 3176 assert((OpportunisticVTables.empty() || shouldOpportunisticallyEmitVTables()) 3177 && "Only emit opportunistic vtables with optimizations"); 3178 3179 for (const CXXRecordDecl *RD : OpportunisticVTables) { 3180 assert(getVTables().isVTableExternal(RD) && 3181 "This queue should only contain external vtables"); 3182 if (getCXXABI().canSpeculativelyEmitVTable(RD)) 3183 VTables.GenerateClassData(RD); 3184 } 3185 OpportunisticVTables.clear(); 3186 } 3187 3188 void CodeGenModule::EmitGlobalAnnotations() { 3189 for (const auto& [MangledName, VD] : DeferredAnnotations) { 3190 llvm::GlobalValue *GV = GetGlobalValue(MangledName); 3191 if (GV) 3192 AddGlobalAnnotations(VD, GV); 3193 } 3194 DeferredAnnotations.clear(); 3195 3196 if (Annotations.empty()) 3197 return; 3198 3199 // Create a new global variable for the ConstantStruct in the Module. 3200 llvm::Constant *Array = llvm::ConstantArray::get(llvm::ArrayType::get( 3201 Annotations[0]->getType(), Annotations.size()), Annotations); 3202 auto *gv = new llvm::GlobalVariable(getModule(), Array->getType(), false, 3203 llvm::GlobalValue::AppendingLinkage, 3204 Array, "llvm.global.annotations"); 3205 gv->setSection(AnnotationSection); 3206 } 3207 3208 llvm::Constant *CodeGenModule::EmitAnnotationString(StringRef Str) { 3209 llvm::Constant *&AStr = AnnotationStrings[Str]; 3210 if (AStr) 3211 return AStr; 3212 3213 // Not found yet, create a new global. 3214 llvm::Constant *s = llvm::ConstantDataArray::getString(getLLVMContext(), Str); 3215 auto *gv = new llvm::GlobalVariable( 3216 getModule(), s->getType(), true, llvm::GlobalValue::PrivateLinkage, s, 3217 ".str", nullptr, llvm::GlobalValue::NotThreadLocal, 3218 ConstGlobalsPtrTy->getAddressSpace()); 3219 gv->setSection(AnnotationSection); 3220 gv->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3221 AStr = gv; 3222 return gv; 3223 } 3224 3225 llvm::Constant *CodeGenModule::EmitAnnotationUnit(SourceLocation Loc) { 3226 SourceManager &SM = getContext().getSourceManager(); 3227 PresumedLoc PLoc = SM.getPresumedLoc(Loc); 3228 if (PLoc.isValid()) 3229 return EmitAnnotationString(PLoc.getFilename()); 3230 return EmitAnnotationString(SM.getBufferName(Loc)); 3231 } 3232 3233 llvm::Constant *CodeGenModule::EmitAnnotationLineNo(SourceLocation L) { 3234 SourceManager &SM = getContext().getSourceManager(); 3235 PresumedLoc PLoc = SM.getPresumedLoc(L); 3236 unsigned LineNo = PLoc.isValid() ? PLoc.getLine() : 3237 SM.getExpansionLineNumber(L); 3238 return llvm::ConstantInt::get(Int32Ty, LineNo); 3239 } 3240 3241 llvm::Constant *CodeGenModule::EmitAnnotationArgs(const AnnotateAttr *Attr) { 3242 ArrayRef<Expr *> Exprs = {Attr->args_begin(), Attr->args_size()}; 3243 if (Exprs.empty()) 3244 return llvm::ConstantPointerNull::get(ConstGlobalsPtrTy); 3245 3246 llvm::FoldingSetNodeID ID; 3247 for (Expr *E : Exprs) { 3248 ID.Add(cast<clang::ConstantExpr>(E)->getAPValueResult()); 3249 } 3250 llvm::Constant *&Lookup = AnnotationArgs[ID.ComputeHash()]; 3251 if (Lookup) 3252 return Lookup; 3253 3254 llvm::SmallVector<llvm::Constant *, 4> LLVMArgs; 3255 LLVMArgs.reserve(Exprs.size()); 3256 ConstantEmitter ConstEmiter(*this); 3257 llvm::transform(Exprs, std::back_inserter(LLVMArgs), [&](const Expr *E) { 3258 const auto *CE = cast<clang::ConstantExpr>(E); 3259 return ConstEmiter.emitAbstract(CE->getBeginLoc(), CE->getAPValueResult(), 3260 CE->getType()); 3261 }); 3262 auto *Struct = llvm::ConstantStruct::getAnon(LLVMArgs); 3263 auto *GV = new llvm::GlobalVariable(getModule(), Struct->getType(), true, 3264 llvm::GlobalValue::PrivateLinkage, Struct, 3265 ".args"); 3266 GV->setSection(AnnotationSection); 3267 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3268 3269 Lookup = GV; 3270 return GV; 3271 } 3272 3273 llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV, 3274 const AnnotateAttr *AA, 3275 SourceLocation L) { 3276 // Get the globals for file name, annotation, and the line number. 3277 llvm::Constant *AnnoGV = EmitAnnotationString(AA->getAnnotation()), 3278 *UnitGV = EmitAnnotationUnit(L), 3279 *LineNoCst = EmitAnnotationLineNo(L), 3280 *Args = EmitAnnotationArgs(AA); 3281 3282 llvm::Constant *GVInGlobalsAS = GV; 3283 if (GV->getAddressSpace() != 3284 getDataLayout().getDefaultGlobalsAddressSpace()) { 3285 GVInGlobalsAS = llvm::ConstantExpr::getAddrSpaceCast( 3286 GV, 3287 llvm::PointerType::get( 3288 GV->getContext(), getDataLayout().getDefaultGlobalsAddressSpace())); 3289 } 3290 3291 // Create the ConstantStruct for the global annotation. 3292 llvm::Constant *Fields[] = { 3293 GVInGlobalsAS, AnnoGV, UnitGV, LineNoCst, Args, 3294 }; 3295 return llvm::ConstantStruct::getAnon(Fields); 3296 } 3297 3298 void CodeGenModule::AddGlobalAnnotations(const ValueDecl *D, 3299 llvm::GlobalValue *GV) { 3300 assert(D->hasAttr<AnnotateAttr>() && "no annotate attribute"); 3301 // Get the struct elements for these annotations. 3302 for (const auto *I : D->specific_attrs<AnnotateAttr>()) 3303 Annotations.push_back(EmitAnnotateAttr(GV, I, D->getLocation())); 3304 } 3305 3306 bool CodeGenModule::isInNoSanitizeList(SanitizerMask Kind, llvm::Function *Fn, 3307 SourceLocation Loc) const { 3308 const auto &NoSanitizeL = getContext().getNoSanitizeList(); 3309 // NoSanitize by function name. 3310 if (NoSanitizeL.containsFunction(Kind, Fn->getName())) 3311 return true; 3312 // NoSanitize by location. Check "mainfile" prefix. 3313 auto &SM = Context.getSourceManager(); 3314 FileEntryRef MainFile = *SM.getFileEntryRefForID(SM.getMainFileID()); 3315 if (NoSanitizeL.containsMainFile(Kind, MainFile.getName())) 3316 return true; 3317 3318 // Check "src" prefix. 3319 if (Loc.isValid()) 3320 return NoSanitizeL.containsLocation(Kind, Loc); 3321 // If location is unknown, this may be a compiler-generated function. Assume 3322 // it's located in the main file. 3323 return NoSanitizeL.containsFile(Kind, MainFile.getName()); 3324 } 3325 3326 bool CodeGenModule::isInNoSanitizeList(SanitizerMask Kind, 3327 llvm::GlobalVariable *GV, 3328 SourceLocation Loc, QualType Ty, 3329 StringRef Category) const { 3330 const auto &NoSanitizeL = getContext().getNoSanitizeList(); 3331 if (NoSanitizeL.containsGlobal(Kind, GV->getName(), Category)) 3332 return true; 3333 auto &SM = Context.getSourceManager(); 3334 if (NoSanitizeL.containsMainFile( 3335 Kind, SM.getFileEntryRefForID(SM.getMainFileID())->getName(), 3336 Category)) 3337 return true; 3338 if (NoSanitizeL.containsLocation(Kind, Loc, Category)) 3339 return true; 3340 3341 // Check global type. 3342 if (!Ty.isNull()) { 3343 // Drill down the array types: if global variable of a fixed type is 3344 // not sanitized, we also don't instrument arrays of them. 3345 while (auto AT = dyn_cast<ArrayType>(Ty.getTypePtr())) 3346 Ty = AT->getElementType(); 3347 Ty = Ty.getCanonicalType().getUnqualifiedType(); 3348 // Only record types (classes, structs etc.) are ignored. 3349 if (Ty->isRecordType()) { 3350 std::string TypeStr = Ty.getAsString(getContext().getPrintingPolicy()); 3351 if (NoSanitizeL.containsType(Kind, TypeStr, Category)) 3352 return true; 3353 } 3354 } 3355 return false; 3356 } 3357 3358 bool CodeGenModule::imbueXRayAttrs(llvm::Function *Fn, SourceLocation Loc, 3359 StringRef Category) const { 3360 const auto &XRayFilter = getContext().getXRayFilter(); 3361 using ImbueAttr = XRayFunctionFilter::ImbueAttribute; 3362 auto Attr = ImbueAttr::NONE; 3363 if (Loc.isValid()) 3364 Attr = XRayFilter.shouldImbueLocation(Loc, Category); 3365 if (Attr == ImbueAttr::NONE) 3366 Attr = XRayFilter.shouldImbueFunction(Fn->getName()); 3367 switch (Attr) { 3368 case ImbueAttr::NONE: 3369 return false; 3370 case ImbueAttr::ALWAYS: 3371 Fn->addFnAttr("function-instrument", "xray-always"); 3372 break; 3373 case ImbueAttr::ALWAYS_ARG1: 3374 Fn->addFnAttr("function-instrument", "xray-always"); 3375 Fn->addFnAttr("xray-log-args", "1"); 3376 break; 3377 case ImbueAttr::NEVER: 3378 Fn->addFnAttr("function-instrument", "xray-never"); 3379 break; 3380 } 3381 return true; 3382 } 3383 3384 ProfileList::ExclusionType 3385 CodeGenModule::isFunctionBlockedByProfileList(llvm::Function *Fn, 3386 SourceLocation Loc) const { 3387 const auto &ProfileList = getContext().getProfileList(); 3388 // If the profile list is empty, then instrument everything. 3389 if (ProfileList.isEmpty()) 3390 return ProfileList::Allow; 3391 CodeGenOptions::ProfileInstrKind Kind = getCodeGenOpts().getProfileInstr(); 3392 // First, check the function name. 3393 if (auto V = ProfileList.isFunctionExcluded(Fn->getName(), Kind)) 3394 return *V; 3395 // Next, check the source location. 3396 if (Loc.isValid()) 3397 if (auto V = ProfileList.isLocationExcluded(Loc, Kind)) 3398 return *V; 3399 // If location is unknown, this may be a compiler-generated function. Assume 3400 // it's located in the main file. 3401 auto &SM = Context.getSourceManager(); 3402 if (auto MainFile = SM.getFileEntryRefForID(SM.getMainFileID())) 3403 if (auto V = ProfileList.isFileExcluded(MainFile->getName(), Kind)) 3404 return *V; 3405 return ProfileList.getDefault(Kind); 3406 } 3407 3408 ProfileList::ExclusionType 3409 CodeGenModule::isFunctionBlockedFromProfileInstr(llvm::Function *Fn, 3410 SourceLocation Loc) const { 3411 auto V = isFunctionBlockedByProfileList(Fn, Loc); 3412 if (V != ProfileList::Allow) 3413 return V; 3414 3415 auto NumGroups = getCodeGenOpts().ProfileTotalFunctionGroups; 3416 if (NumGroups > 1) { 3417 auto Group = llvm::crc32(arrayRefFromStringRef(Fn->getName())) % NumGroups; 3418 if (Group != getCodeGenOpts().ProfileSelectedFunctionGroup) 3419 return ProfileList::Skip; 3420 } 3421 return ProfileList::Allow; 3422 } 3423 3424 bool CodeGenModule::MustBeEmitted(const ValueDecl *Global) { 3425 // Never defer when EmitAllDecls is specified. 3426 if (LangOpts.EmitAllDecls) 3427 return true; 3428 3429 const auto *VD = dyn_cast<VarDecl>(Global); 3430 if (VD && 3431 ((CodeGenOpts.KeepPersistentStorageVariables && 3432 (VD->getStorageDuration() == SD_Static || 3433 VD->getStorageDuration() == SD_Thread)) || 3434 (CodeGenOpts.KeepStaticConsts && VD->getStorageDuration() == SD_Static && 3435 VD->getType().isConstQualified()))) 3436 return true; 3437 3438 return getContext().DeclMustBeEmitted(Global); 3439 } 3440 3441 bool CodeGenModule::MayBeEmittedEagerly(const ValueDecl *Global) { 3442 // In OpenMP 5.0 variables and function may be marked as 3443 // device_type(host/nohost) and we should not emit them eagerly unless we sure 3444 // that they must be emitted on the host/device. To be sure we need to have 3445 // seen a declare target with an explicit mentioning of the function, we know 3446 // we have if the level of the declare target attribute is -1. Note that we 3447 // check somewhere else if we should emit this at all. 3448 if (LangOpts.OpenMP >= 50 && !LangOpts.OpenMPSimd) { 3449 std::optional<OMPDeclareTargetDeclAttr *> ActiveAttr = 3450 OMPDeclareTargetDeclAttr::getActiveAttr(Global); 3451 if (!ActiveAttr || (*ActiveAttr)->getLevel() != (unsigned)-1) 3452 return false; 3453 } 3454 3455 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) { 3456 if (FD->getTemplateSpecializationKind() == TSK_ImplicitInstantiation) 3457 // Implicit template instantiations may change linkage if they are later 3458 // explicitly instantiated, so they should not be emitted eagerly. 3459 return false; 3460 // Defer until all versions have been semantically checked. 3461 if (FD->hasAttr<TargetVersionAttr>() && !FD->isMultiVersion()) 3462 return false; 3463 } 3464 if (const auto *VD = dyn_cast<VarDecl>(Global)) { 3465 if (Context.getInlineVariableDefinitionKind(VD) == 3466 ASTContext::InlineVariableDefinitionKind::WeakUnknown) 3467 // A definition of an inline constexpr static data member may change 3468 // linkage later if it's redeclared outside the class. 3469 return false; 3470 if (CXX20ModuleInits && VD->getOwningModule() && 3471 !VD->getOwningModule()->isModuleMapModule()) { 3472 // For CXX20, module-owned initializers need to be deferred, since it is 3473 // not known at this point if they will be run for the current module or 3474 // as part of the initializer for an imported one. 3475 return false; 3476 } 3477 } 3478 // If OpenMP is enabled and threadprivates must be generated like TLS, delay 3479 // codegen for global variables, because they may be marked as threadprivate. 3480 if (LangOpts.OpenMP && LangOpts.OpenMPUseTLS && 3481 getContext().getTargetInfo().isTLSSupported() && isa<VarDecl>(Global) && 3482 !Global->getType().isConstantStorage(getContext(), false, false) && 3483 !OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(Global)) 3484 return false; 3485 3486 return true; 3487 } 3488 3489 ConstantAddress CodeGenModule::GetAddrOfMSGuidDecl(const MSGuidDecl *GD) { 3490 StringRef Name = getMangledName(GD); 3491 3492 // The UUID descriptor should be pointer aligned. 3493 CharUnits Alignment = CharUnits::fromQuantity(PointerAlignInBytes); 3494 3495 // Look for an existing global. 3496 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name)) 3497 return ConstantAddress(GV, GV->getValueType(), Alignment); 3498 3499 ConstantEmitter Emitter(*this); 3500 llvm::Constant *Init; 3501 3502 APValue &V = GD->getAsAPValue(); 3503 if (!V.isAbsent()) { 3504 // If possible, emit the APValue version of the initializer. In particular, 3505 // this gets the type of the constant right. 3506 Init = Emitter.emitForInitializer( 3507 GD->getAsAPValue(), GD->getType().getAddressSpace(), GD->getType()); 3508 } else { 3509 // As a fallback, directly construct the constant. 3510 // FIXME: This may get padding wrong under esoteric struct layout rules. 3511 // MSVC appears to create a complete type 'struct __s_GUID' that it 3512 // presumably uses to represent these constants. 3513 MSGuidDecl::Parts Parts = GD->getParts(); 3514 llvm::Constant *Fields[4] = { 3515 llvm::ConstantInt::get(Int32Ty, Parts.Part1), 3516 llvm::ConstantInt::get(Int16Ty, Parts.Part2), 3517 llvm::ConstantInt::get(Int16Ty, Parts.Part3), 3518 llvm::ConstantDataArray::getRaw( 3519 StringRef(reinterpret_cast<char *>(Parts.Part4And5), 8), 8, 3520 Int8Ty)}; 3521 Init = llvm::ConstantStruct::getAnon(Fields); 3522 } 3523 3524 auto *GV = new llvm::GlobalVariable( 3525 getModule(), Init->getType(), 3526 /*isConstant=*/true, llvm::GlobalValue::LinkOnceODRLinkage, Init, Name); 3527 if (supportsCOMDAT()) 3528 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 3529 setDSOLocal(GV); 3530 3531 if (!V.isAbsent()) { 3532 Emitter.finalize(GV); 3533 return ConstantAddress(GV, GV->getValueType(), Alignment); 3534 } 3535 3536 llvm::Type *Ty = getTypes().ConvertTypeForMem(GD->getType()); 3537 return ConstantAddress(GV, Ty, Alignment); 3538 } 3539 3540 ConstantAddress CodeGenModule::GetAddrOfUnnamedGlobalConstantDecl( 3541 const UnnamedGlobalConstantDecl *GCD) { 3542 CharUnits Alignment = getContext().getTypeAlignInChars(GCD->getType()); 3543 3544 llvm::GlobalVariable **Entry = nullptr; 3545 Entry = &UnnamedGlobalConstantDeclMap[GCD]; 3546 if (*Entry) 3547 return ConstantAddress(*Entry, (*Entry)->getValueType(), Alignment); 3548 3549 ConstantEmitter Emitter(*this); 3550 llvm::Constant *Init; 3551 3552 const APValue &V = GCD->getValue(); 3553 3554 assert(!V.isAbsent()); 3555 Init = Emitter.emitForInitializer(V, GCD->getType().getAddressSpace(), 3556 GCD->getType()); 3557 3558 auto *GV = new llvm::GlobalVariable(getModule(), Init->getType(), 3559 /*isConstant=*/true, 3560 llvm::GlobalValue::PrivateLinkage, Init, 3561 ".constant"); 3562 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 3563 GV->setAlignment(Alignment.getAsAlign()); 3564 3565 Emitter.finalize(GV); 3566 3567 *Entry = GV; 3568 return ConstantAddress(GV, GV->getValueType(), Alignment); 3569 } 3570 3571 ConstantAddress CodeGenModule::GetAddrOfTemplateParamObject( 3572 const TemplateParamObjectDecl *TPO) { 3573 StringRef Name = getMangledName(TPO); 3574 CharUnits Alignment = getNaturalTypeAlignment(TPO->getType()); 3575 3576 if (llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name)) 3577 return ConstantAddress(GV, GV->getValueType(), Alignment); 3578 3579 ConstantEmitter Emitter(*this); 3580 llvm::Constant *Init = Emitter.emitForInitializer( 3581 TPO->getValue(), TPO->getType().getAddressSpace(), TPO->getType()); 3582 3583 if (!Init) { 3584 ErrorUnsupported(TPO, "template parameter object"); 3585 return ConstantAddress::invalid(); 3586 } 3587 3588 llvm::GlobalValue::LinkageTypes Linkage = 3589 isExternallyVisible(TPO->getLinkageAndVisibility().getLinkage()) 3590 ? llvm::GlobalValue::LinkOnceODRLinkage 3591 : llvm::GlobalValue::InternalLinkage; 3592 auto *GV = new llvm::GlobalVariable(getModule(), Init->getType(), 3593 /*isConstant=*/true, Linkage, Init, Name); 3594 setGVProperties(GV, TPO); 3595 if (supportsCOMDAT()) 3596 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 3597 Emitter.finalize(GV); 3598 3599 return ConstantAddress(GV, GV->getValueType(), Alignment); 3600 } 3601 3602 ConstantAddress CodeGenModule::GetWeakRefReference(const ValueDecl *VD) { 3603 const AliasAttr *AA = VD->getAttr<AliasAttr>(); 3604 assert(AA && "No alias?"); 3605 3606 CharUnits Alignment = getContext().getDeclAlign(VD); 3607 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(VD->getType()); 3608 3609 // See if there is already something with the target's name in the module. 3610 llvm::GlobalValue *Entry = GetGlobalValue(AA->getAliasee()); 3611 if (Entry) 3612 return ConstantAddress(Entry, DeclTy, Alignment); 3613 3614 llvm::Constant *Aliasee; 3615 if (isa<llvm::FunctionType>(DeclTy)) 3616 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, 3617 GlobalDecl(cast<FunctionDecl>(VD)), 3618 /*ForVTable=*/false); 3619 else 3620 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, LangAS::Default, 3621 nullptr); 3622 3623 auto *F = cast<llvm::GlobalValue>(Aliasee); 3624 F->setLinkage(llvm::Function::ExternalWeakLinkage); 3625 WeakRefReferences.insert(F); 3626 3627 return ConstantAddress(Aliasee, DeclTy, Alignment); 3628 } 3629 3630 template <typename AttrT> static bool hasImplicitAttr(const ValueDecl *D) { 3631 if (!D) 3632 return false; 3633 if (auto *A = D->getAttr<AttrT>()) 3634 return A->isImplicit(); 3635 return D->isImplicit(); 3636 } 3637 3638 void CodeGenModule::EmitGlobal(GlobalDecl GD) { 3639 const auto *Global = cast<ValueDecl>(GD.getDecl()); 3640 3641 // Weak references don't produce any output by themselves. 3642 if (Global->hasAttr<WeakRefAttr>()) 3643 return; 3644 3645 // If this is an alias definition (which otherwise looks like a declaration) 3646 // emit it now. 3647 if (Global->hasAttr<AliasAttr>()) 3648 return EmitAliasDefinition(GD); 3649 3650 // IFunc like an alias whose value is resolved at runtime by calling resolver. 3651 if (Global->hasAttr<IFuncAttr>()) 3652 return emitIFuncDefinition(GD); 3653 3654 // If this is a cpu_dispatch multiversion function, emit the resolver. 3655 if (Global->hasAttr<CPUDispatchAttr>()) 3656 return emitCPUDispatchDefinition(GD); 3657 3658 // If this is CUDA, be selective about which declarations we emit. 3659 // Non-constexpr non-lambda implicit host device functions are not emitted 3660 // unless they are used on device side. 3661 if (LangOpts.CUDA) { 3662 if (LangOpts.CUDAIsDevice) { 3663 const auto *FD = dyn_cast<FunctionDecl>(Global); 3664 if ((!Global->hasAttr<CUDADeviceAttr>() || 3665 (LangOpts.OffloadImplicitHostDeviceTemplates && FD && 3666 hasImplicitAttr<CUDAHostAttr>(FD) && 3667 hasImplicitAttr<CUDADeviceAttr>(FD) && !FD->isConstexpr() && 3668 !isLambdaCallOperator(FD) && 3669 !getContext().CUDAImplicitHostDeviceFunUsedByDevice.count(FD))) && 3670 !Global->hasAttr<CUDAGlobalAttr>() && 3671 !Global->hasAttr<CUDAConstantAttr>() && 3672 !Global->hasAttr<CUDASharedAttr>() && 3673 !Global->getType()->isCUDADeviceBuiltinSurfaceType() && 3674 !Global->getType()->isCUDADeviceBuiltinTextureType() && 3675 !(LangOpts.HIPStdPar && isa<FunctionDecl>(Global) && 3676 !Global->hasAttr<CUDAHostAttr>())) 3677 return; 3678 } else { 3679 // We need to emit host-side 'shadows' for all global 3680 // device-side variables because the CUDA runtime needs their 3681 // size and host-side address in order to provide access to 3682 // their device-side incarnations. 3683 3684 // So device-only functions are the only things we skip. 3685 if (isa<FunctionDecl>(Global) && !Global->hasAttr<CUDAHostAttr>() && 3686 Global->hasAttr<CUDADeviceAttr>()) 3687 return; 3688 3689 assert((isa<FunctionDecl>(Global) || isa<VarDecl>(Global)) && 3690 "Expected Variable or Function"); 3691 } 3692 } 3693 3694 if (LangOpts.OpenMP) { 3695 // If this is OpenMP, check if it is legal to emit this global normally. 3696 if (OpenMPRuntime && OpenMPRuntime->emitTargetGlobal(GD)) 3697 return; 3698 if (auto *DRD = dyn_cast<OMPDeclareReductionDecl>(Global)) { 3699 if (MustBeEmitted(Global)) 3700 EmitOMPDeclareReduction(DRD); 3701 return; 3702 } 3703 if (auto *DMD = dyn_cast<OMPDeclareMapperDecl>(Global)) { 3704 if (MustBeEmitted(Global)) 3705 EmitOMPDeclareMapper(DMD); 3706 return; 3707 } 3708 } 3709 3710 // Ignore declarations, they will be emitted on their first use. 3711 if (const auto *FD = dyn_cast<FunctionDecl>(Global)) { 3712 // Update deferred annotations with the latest declaration if the function 3713 // function was already used or defined. 3714 if (FD->hasAttr<AnnotateAttr>()) { 3715 StringRef MangledName = getMangledName(GD); 3716 if (GetGlobalValue(MangledName)) 3717 DeferredAnnotations[MangledName] = FD; 3718 } 3719 3720 // Forward declarations are emitted lazily on first use. 3721 if (!FD->doesThisDeclarationHaveABody()) { 3722 if (!FD->doesDeclarationForceExternallyVisibleDefinition() && 3723 (!FD->isMultiVersion() || 3724 !FD->getASTContext().getTargetInfo().getTriple().isAArch64())) 3725 return; 3726 3727 StringRef MangledName = getMangledName(GD); 3728 3729 // Compute the function info and LLVM type. 3730 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 3731 llvm::Type *Ty = getTypes().GetFunctionType(FI); 3732 3733 GetOrCreateLLVMFunction(MangledName, Ty, GD, /*ForVTable=*/false, 3734 /*DontDefer=*/false); 3735 return; 3736 } 3737 } else { 3738 const auto *VD = cast<VarDecl>(Global); 3739 assert(VD->isFileVarDecl() && "Cannot emit local var decl as global."); 3740 if (VD->isThisDeclarationADefinition() != VarDecl::Definition && 3741 !Context.isMSStaticDataMemberInlineDefinition(VD)) { 3742 if (LangOpts.OpenMP) { 3743 // Emit declaration of the must-be-emitted declare target variable. 3744 if (std::optional<OMPDeclareTargetDeclAttr::MapTypeTy> Res = 3745 OMPDeclareTargetDeclAttr::isDeclareTargetDeclaration(VD)) { 3746 3747 // If this variable has external storage and doesn't require special 3748 // link handling we defer to its canonical definition. 3749 if (VD->hasExternalStorage() && 3750 Res != OMPDeclareTargetDeclAttr::MT_Link) 3751 return; 3752 3753 bool UnifiedMemoryEnabled = 3754 getOpenMPRuntime().hasRequiresUnifiedSharedMemory(); 3755 if ((*Res == OMPDeclareTargetDeclAttr::MT_To || 3756 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 3757 !UnifiedMemoryEnabled) { 3758 (void)GetAddrOfGlobalVar(VD); 3759 } else { 3760 assert(((*Res == OMPDeclareTargetDeclAttr::MT_Link) || 3761 ((*Res == OMPDeclareTargetDeclAttr::MT_To || 3762 *Res == OMPDeclareTargetDeclAttr::MT_Enter) && 3763 UnifiedMemoryEnabled)) && 3764 "Link clause or to clause with unified memory expected."); 3765 (void)getOpenMPRuntime().getAddrOfDeclareTargetVar(VD); 3766 } 3767 3768 return; 3769 } 3770 } 3771 // If this declaration may have caused an inline variable definition to 3772 // change linkage, make sure that it's emitted. 3773 if (Context.getInlineVariableDefinitionKind(VD) == 3774 ASTContext::InlineVariableDefinitionKind::Strong) 3775 GetAddrOfGlobalVar(VD); 3776 return; 3777 } 3778 } 3779 3780 // Defer code generation to first use when possible, e.g. if this is an inline 3781 // function. If the global must always be emitted, do it eagerly if possible 3782 // to benefit from cache locality. 3783 if (MustBeEmitted(Global) && MayBeEmittedEagerly(Global)) { 3784 // Emit the definition if it can't be deferred. 3785 EmitGlobalDefinition(GD); 3786 addEmittedDeferredDecl(GD); 3787 return; 3788 } 3789 3790 // If we're deferring emission of a C++ variable with an 3791 // initializer, remember the order in which it appeared in the file. 3792 if (getLangOpts().CPlusPlus && isa<VarDecl>(Global) && 3793 cast<VarDecl>(Global)->hasInit()) { 3794 DelayedCXXInitPosition[Global] = CXXGlobalInits.size(); 3795 CXXGlobalInits.push_back(nullptr); 3796 } 3797 3798 StringRef MangledName = getMangledName(GD); 3799 if (GetGlobalValue(MangledName) != nullptr) { 3800 // The value has already been used and should therefore be emitted. 3801 addDeferredDeclToEmit(GD); 3802 } else if (MustBeEmitted(Global)) { 3803 // The value must be emitted, but cannot be emitted eagerly. 3804 assert(!MayBeEmittedEagerly(Global)); 3805 addDeferredDeclToEmit(GD); 3806 } else { 3807 // Otherwise, remember that we saw a deferred decl with this name. The 3808 // first use of the mangled name will cause it to move into 3809 // DeferredDeclsToEmit. 3810 DeferredDecls[MangledName] = GD; 3811 } 3812 } 3813 3814 // Check if T is a class type with a destructor that's not dllimport. 3815 static bool HasNonDllImportDtor(QualType T) { 3816 if (const auto *RT = T->getBaseElementTypeUnsafe()->getAs<RecordType>()) 3817 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) 3818 if (RD->getDestructor() && !RD->getDestructor()->hasAttr<DLLImportAttr>()) 3819 return true; 3820 3821 return false; 3822 } 3823 3824 namespace { 3825 struct FunctionIsDirectlyRecursive 3826 : public ConstStmtVisitor<FunctionIsDirectlyRecursive, bool> { 3827 const StringRef Name; 3828 const Builtin::Context &BI; 3829 FunctionIsDirectlyRecursive(StringRef N, const Builtin::Context &C) 3830 : Name(N), BI(C) {} 3831 3832 bool VisitCallExpr(const CallExpr *E) { 3833 const FunctionDecl *FD = E->getDirectCallee(); 3834 if (!FD) 3835 return false; 3836 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>(); 3837 if (Attr && Name == Attr->getLabel()) 3838 return true; 3839 unsigned BuiltinID = FD->getBuiltinID(); 3840 if (!BuiltinID || !BI.isLibFunction(BuiltinID)) 3841 return false; 3842 StringRef BuiltinName = BI.getName(BuiltinID); 3843 if (BuiltinName.starts_with("__builtin_") && 3844 Name == BuiltinName.slice(strlen("__builtin_"), StringRef::npos)) { 3845 return true; 3846 } 3847 return false; 3848 } 3849 3850 bool VisitStmt(const Stmt *S) { 3851 for (const Stmt *Child : S->children()) 3852 if (Child && this->Visit(Child)) 3853 return true; 3854 return false; 3855 } 3856 }; 3857 3858 // Make sure we're not referencing non-imported vars or functions. 3859 struct DLLImportFunctionVisitor 3860 : public RecursiveASTVisitor<DLLImportFunctionVisitor> { 3861 bool SafeToInline = true; 3862 3863 bool shouldVisitImplicitCode() const { return true; } 3864 3865 bool VisitVarDecl(VarDecl *VD) { 3866 if (VD->getTLSKind()) { 3867 // A thread-local variable cannot be imported. 3868 SafeToInline = false; 3869 return SafeToInline; 3870 } 3871 3872 // A variable definition might imply a destructor call. 3873 if (VD->isThisDeclarationADefinition()) 3874 SafeToInline = !HasNonDllImportDtor(VD->getType()); 3875 3876 return SafeToInline; 3877 } 3878 3879 bool VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) { 3880 if (const auto *D = E->getTemporary()->getDestructor()) 3881 SafeToInline = D->hasAttr<DLLImportAttr>(); 3882 return SafeToInline; 3883 } 3884 3885 bool VisitDeclRefExpr(DeclRefExpr *E) { 3886 ValueDecl *VD = E->getDecl(); 3887 if (isa<FunctionDecl>(VD)) 3888 SafeToInline = VD->hasAttr<DLLImportAttr>(); 3889 else if (VarDecl *V = dyn_cast<VarDecl>(VD)) 3890 SafeToInline = !V->hasGlobalStorage() || V->hasAttr<DLLImportAttr>(); 3891 return SafeToInline; 3892 } 3893 3894 bool VisitCXXConstructExpr(CXXConstructExpr *E) { 3895 SafeToInline = E->getConstructor()->hasAttr<DLLImportAttr>(); 3896 return SafeToInline; 3897 } 3898 3899 bool VisitCXXMemberCallExpr(CXXMemberCallExpr *E) { 3900 CXXMethodDecl *M = E->getMethodDecl(); 3901 if (!M) { 3902 // Call through a pointer to member function. This is safe to inline. 3903 SafeToInline = true; 3904 } else { 3905 SafeToInline = M->hasAttr<DLLImportAttr>(); 3906 } 3907 return SafeToInline; 3908 } 3909 3910 bool VisitCXXDeleteExpr(CXXDeleteExpr *E) { 3911 SafeToInline = E->getOperatorDelete()->hasAttr<DLLImportAttr>(); 3912 return SafeToInline; 3913 } 3914 3915 bool VisitCXXNewExpr(CXXNewExpr *E) { 3916 SafeToInline = E->getOperatorNew()->hasAttr<DLLImportAttr>(); 3917 return SafeToInline; 3918 } 3919 }; 3920 } 3921 3922 // isTriviallyRecursive - Check if this function calls another 3923 // decl that, because of the asm attribute or the other decl being a builtin, 3924 // ends up pointing to itself. 3925 bool 3926 CodeGenModule::isTriviallyRecursive(const FunctionDecl *FD) { 3927 StringRef Name; 3928 if (getCXXABI().getMangleContext().shouldMangleDeclName(FD)) { 3929 // asm labels are a special kind of mangling we have to support. 3930 AsmLabelAttr *Attr = FD->getAttr<AsmLabelAttr>(); 3931 if (!Attr) 3932 return false; 3933 Name = Attr->getLabel(); 3934 } else { 3935 Name = FD->getName(); 3936 } 3937 3938 FunctionIsDirectlyRecursive Walker(Name, Context.BuiltinInfo); 3939 const Stmt *Body = FD->getBody(); 3940 return Body ? Walker.Visit(Body) : false; 3941 } 3942 3943 bool CodeGenModule::shouldEmitFunction(GlobalDecl GD) { 3944 if (getFunctionLinkage(GD) != llvm::Function::AvailableExternallyLinkage) 3945 return true; 3946 3947 const auto *F = cast<FunctionDecl>(GD.getDecl()); 3948 if (CodeGenOpts.OptimizationLevel == 0 && !F->hasAttr<AlwaysInlineAttr>()) 3949 return false; 3950 3951 // We don't import function bodies from other named module units since that 3952 // behavior may break ABI compatibility of the current unit. 3953 if (const Module *M = F->getOwningModule(); 3954 M && M->getTopLevelModule()->isNamedModule() && 3955 getContext().getCurrentNamedModule() != M->getTopLevelModule() && 3956 !F->hasAttr<AlwaysInlineAttr>()) 3957 return false; 3958 3959 if (F->hasAttr<NoInlineAttr>()) 3960 return false; 3961 3962 if (F->hasAttr<DLLImportAttr>() && !F->hasAttr<AlwaysInlineAttr>()) { 3963 // Check whether it would be safe to inline this dllimport function. 3964 DLLImportFunctionVisitor Visitor; 3965 Visitor.TraverseFunctionDecl(const_cast<FunctionDecl*>(F)); 3966 if (!Visitor.SafeToInline) 3967 return false; 3968 3969 if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(F)) { 3970 // Implicit destructor invocations aren't captured in the AST, so the 3971 // check above can't see them. Check for them manually here. 3972 for (const Decl *Member : Dtor->getParent()->decls()) 3973 if (isa<FieldDecl>(Member)) 3974 if (HasNonDllImportDtor(cast<FieldDecl>(Member)->getType())) 3975 return false; 3976 for (const CXXBaseSpecifier &B : Dtor->getParent()->bases()) 3977 if (HasNonDllImportDtor(B.getType())) 3978 return false; 3979 } 3980 } 3981 3982 // Inline builtins declaration must be emitted. They often are fortified 3983 // functions. 3984 if (F->isInlineBuiltinDeclaration()) 3985 return true; 3986 3987 // PR9614. Avoid cases where the source code is lying to us. An available 3988 // externally function should have an equivalent function somewhere else, 3989 // but a function that calls itself through asm label/`__builtin_` trickery is 3990 // clearly not equivalent to the real implementation. 3991 // This happens in glibc's btowc and in some configure checks. 3992 return !isTriviallyRecursive(F); 3993 } 3994 3995 bool CodeGenModule::shouldOpportunisticallyEmitVTables() { 3996 return CodeGenOpts.OptimizationLevel > 0; 3997 } 3998 3999 void CodeGenModule::EmitMultiVersionFunctionDefinition(GlobalDecl GD, 4000 llvm::GlobalValue *GV) { 4001 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4002 4003 if (FD->isCPUSpecificMultiVersion()) { 4004 auto *Spec = FD->getAttr<CPUSpecificAttr>(); 4005 for (unsigned I = 0; I < Spec->cpus_size(); ++I) 4006 EmitGlobalFunctionDefinition(GD.getWithMultiVersionIndex(I), nullptr); 4007 } else if (auto *TC = FD->getAttr<TargetClonesAttr>()) { 4008 for (unsigned I = 0; I < TC->featuresStrs_size(); ++I) 4009 // AArch64 favors the default target version over the clone if any. 4010 if ((!TC->isDefaultVersion(I) || !getTarget().getTriple().isAArch64()) && 4011 TC->isFirstOfVersion(I)) 4012 EmitGlobalFunctionDefinition(GD.getWithMultiVersionIndex(I), nullptr); 4013 // Ensure that the resolver function is also emitted. 4014 GetOrCreateMultiVersionResolver(GD); 4015 } else 4016 EmitGlobalFunctionDefinition(GD, GV); 4017 4018 // Defer the resolver emission until we can reason whether the TU 4019 // contains a default target version implementation. 4020 if (FD->isTargetVersionMultiVersion()) 4021 AddDeferredMultiVersionResolverToEmit(GD); 4022 } 4023 4024 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD, llvm::GlobalValue *GV) { 4025 const auto *D = cast<ValueDecl>(GD.getDecl()); 4026 4027 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(), 4028 Context.getSourceManager(), 4029 "Generating code for declaration"); 4030 4031 if (const auto *FD = dyn_cast<FunctionDecl>(D)) { 4032 // At -O0, don't generate IR for functions with available_externally 4033 // linkage. 4034 if (!shouldEmitFunction(GD)) 4035 return; 4036 4037 llvm::TimeTraceScope TimeScope("CodeGen Function", [&]() { 4038 std::string Name; 4039 llvm::raw_string_ostream OS(Name); 4040 FD->getNameForDiagnostic(OS, getContext().getPrintingPolicy(), 4041 /*Qualified=*/true); 4042 return Name; 4043 }); 4044 4045 if (const auto *Method = dyn_cast<CXXMethodDecl>(D)) { 4046 // Make sure to emit the definition(s) before we emit the thunks. 4047 // This is necessary for the generation of certain thunks. 4048 if (isa<CXXConstructorDecl>(Method) || isa<CXXDestructorDecl>(Method)) 4049 ABI->emitCXXStructor(GD); 4050 else if (FD->isMultiVersion()) 4051 EmitMultiVersionFunctionDefinition(GD, GV); 4052 else 4053 EmitGlobalFunctionDefinition(GD, GV); 4054 4055 if (Method->isVirtual()) 4056 getVTables().EmitThunks(GD); 4057 4058 return; 4059 } 4060 4061 if (FD->isMultiVersion()) 4062 return EmitMultiVersionFunctionDefinition(GD, GV); 4063 return EmitGlobalFunctionDefinition(GD, GV); 4064 } 4065 4066 if (const auto *VD = dyn_cast<VarDecl>(D)) 4067 return EmitGlobalVarDefinition(VD, !VD->hasDefinition()); 4068 4069 llvm_unreachable("Invalid argument to EmitGlobalDefinition()"); 4070 } 4071 4072 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 4073 llvm::Function *NewFn); 4074 4075 static unsigned 4076 TargetMVPriority(const TargetInfo &TI, 4077 const CodeGenFunction::MultiVersionResolverOption &RO) { 4078 unsigned Priority = 0; 4079 unsigned NumFeatures = 0; 4080 for (StringRef Feat : RO.Conditions.Features) { 4081 Priority = std::max(Priority, TI.multiVersionSortPriority(Feat)); 4082 NumFeatures++; 4083 } 4084 4085 if (!RO.Conditions.Architecture.empty()) 4086 Priority = std::max( 4087 Priority, TI.multiVersionSortPriority(RO.Conditions.Architecture)); 4088 4089 Priority += TI.multiVersionFeatureCost() * NumFeatures; 4090 4091 return Priority; 4092 } 4093 4094 // Multiversion functions should be at most 'WeakODRLinkage' so that a different 4095 // TU can forward declare the function without causing problems. Particularly 4096 // in the cases of CPUDispatch, this causes issues. This also makes sure we 4097 // work with internal linkage functions, so that the same function name can be 4098 // used with internal linkage in multiple TUs. 4099 llvm::GlobalValue::LinkageTypes getMultiversionLinkage(CodeGenModule &CGM, 4100 GlobalDecl GD) { 4101 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 4102 if (FD->getFormalLinkage() == Linkage::Internal) 4103 return llvm::GlobalValue::InternalLinkage; 4104 return llvm::GlobalValue::WeakODRLinkage; 4105 } 4106 4107 static FunctionDecl *createDefaultTargetVersionFrom(const FunctionDecl *FD) { 4108 DeclContext *DeclCtx = FD->getASTContext().getTranslationUnitDecl(); 4109 TypeSourceInfo *TInfo = FD->getTypeSourceInfo(); 4110 StorageClass SC = FD->getStorageClass(); 4111 DeclarationName Name = FD->getNameInfo().getName(); 4112 4113 FunctionDecl *NewDecl = 4114 FunctionDecl::Create(FD->getASTContext(), DeclCtx, FD->getBeginLoc(), 4115 FD->getEndLoc(), Name, TInfo->getType(), TInfo, SC); 4116 4117 NewDecl->setIsMultiVersion(); 4118 NewDecl->addAttr(TargetVersionAttr::CreateImplicit( 4119 NewDecl->getASTContext(), "default", NewDecl->getSourceRange())); 4120 4121 return NewDecl; 4122 } 4123 4124 void CodeGenModule::emitMultiVersionFunctions() { 4125 std::vector<GlobalDecl> MVFuncsToEmit; 4126 MultiVersionFuncs.swap(MVFuncsToEmit); 4127 for (GlobalDecl GD : MVFuncsToEmit) { 4128 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4129 assert(FD && "Expected a FunctionDecl"); 4130 4131 auto createFunction = [&](const FunctionDecl *Decl, unsigned MVIdx = 0) { 4132 GlobalDecl CurGD{Decl->isDefined() ? Decl->getDefinition() : Decl, MVIdx}; 4133 StringRef MangledName = getMangledName(CurGD); 4134 llvm::Constant *Func = GetGlobalValue(MangledName); 4135 if (!Func) { 4136 if (Decl->isDefined()) { 4137 EmitGlobalFunctionDefinition(CurGD, nullptr); 4138 Func = GetGlobalValue(MangledName); 4139 } else { 4140 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(CurGD); 4141 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 4142 Func = GetAddrOfFunction(CurGD, Ty, /*ForVTable=*/false, 4143 /*DontDefer=*/false, ForDefinition); 4144 } 4145 assert(Func && "This should have just been created"); 4146 } 4147 return cast<llvm::Function>(Func); 4148 }; 4149 4150 bool HasDefaultDecl = !FD->isTargetVersionMultiVersion(); 4151 bool ShouldEmitResolver = 4152 !getContext().getTargetInfo().getTriple().isAArch64(); 4153 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options; 4154 4155 getContext().forEachMultiversionedFunctionVersion( 4156 FD, [&](const FunctionDecl *CurFD) { 4157 llvm::SmallVector<StringRef, 8> Feats; 4158 4159 if (const auto *TA = CurFD->getAttr<TargetAttr>()) { 4160 TA->getAddedFeatures(Feats); 4161 llvm::Function *Func = createFunction(CurFD); 4162 Options.emplace_back(Func, TA->getArchitecture(), Feats); 4163 } else if (const auto *TVA = CurFD->getAttr<TargetVersionAttr>()) { 4164 bool HasDefaultDef = TVA->isDefaultVersion() && 4165 CurFD->doesThisDeclarationHaveABody(); 4166 HasDefaultDecl |= TVA->isDefaultVersion(); 4167 ShouldEmitResolver |= (CurFD->isUsed() || HasDefaultDef); 4168 TVA->getFeatures(Feats); 4169 llvm::Function *Func = createFunction(CurFD); 4170 Options.emplace_back(Func, /*Architecture*/ "", Feats); 4171 } else if (const auto *TC = CurFD->getAttr<TargetClonesAttr>()) { 4172 ShouldEmitResolver |= CurFD->doesThisDeclarationHaveABody(); 4173 for (unsigned I = 0; I < TC->featuresStrs_size(); ++I) { 4174 if (!TC->isFirstOfVersion(I)) 4175 continue; 4176 4177 llvm::Function *Func = createFunction(CurFD, I); 4178 StringRef Architecture; 4179 Feats.clear(); 4180 if (getTarget().getTriple().isAArch64()) 4181 TC->getFeatures(Feats, I); 4182 else { 4183 StringRef Version = TC->getFeatureStr(I); 4184 if (Version.starts_with("arch=")) 4185 Architecture = Version.drop_front(sizeof("arch=") - 1); 4186 else if (Version != "default") 4187 Feats.push_back(Version); 4188 } 4189 Options.emplace_back(Func, Architecture, Feats); 4190 } 4191 } else 4192 llvm_unreachable("unexpected MultiVersionKind"); 4193 }); 4194 4195 if (!ShouldEmitResolver) 4196 continue; 4197 4198 if (!HasDefaultDecl) { 4199 FunctionDecl *NewFD = createDefaultTargetVersionFrom(FD); 4200 llvm::Function *Func = createFunction(NewFD); 4201 llvm::SmallVector<StringRef, 1> Feats; 4202 Options.emplace_back(Func, /*Architecture*/ "", Feats); 4203 } 4204 4205 llvm::Constant *ResolverConstant = GetOrCreateMultiVersionResolver(GD); 4206 if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(ResolverConstant)) { 4207 ResolverConstant = IFunc->getResolver(); 4208 if (FD->isTargetClonesMultiVersion() || 4209 FD->isTargetVersionMultiVersion()) { 4210 std::string MangledName = getMangledNameImpl( 4211 *this, GD, FD, /*OmitMultiVersionMangling=*/true); 4212 if (!GetGlobalValue(MangledName + ".ifunc")) { 4213 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4214 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI); 4215 // In prior versions of Clang, the mangling for ifuncs incorrectly 4216 // included an .ifunc suffix. This alias is generated for backward 4217 // compatibility. It is deprecated, and may be removed in the future. 4218 auto *Alias = llvm::GlobalAlias::create( 4219 DeclTy, 0, getMultiversionLinkage(*this, GD), 4220 MangledName + ".ifunc", IFunc, &getModule()); 4221 SetCommonAttributes(FD, Alias); 4222 } 4223 } 4224 } 4225 llvm::Function *ResolverFunc = cast<llvm::Function>(ResolverConstant); 4226 4227 ResolverFunc->setLinkage(getMultiversionLinkage(*this, GD)); 4228 4229 if (!ResolverFunc->hasLocalLinkage() && supportsCOMDAT()) 4230 ResolverFunc->setComdat( 4231 getModule().getOrInsertComdat(ResolverFunc->getName())); 4232 4233 const TargetInfo &TI = getTarget(); 4234 llvm::stable_sort( 4235 Options, [&TI](const CodeGenFunction::MultiVersionResolverOption &LHS, 4236 const CodeGenFunction::MultiVersionResolverOption &RHS) { 4237 return TargetMVPriority(TI, LHS) > TargetMVPriority(TI, RHS); 4238 }); 4239 CodeGenFunction CGF(*this); 4240 CGF.EmitMultiVersionResolver(ResolverFunc, Options); 4241 } 4242 4243 // Ensure that any additions to the deferred decls list caused by emitting a 4244 // variant are emitted. This can happen when the variant itself is inline and 4245 // calls a function without linkage. 4246 if (!MVFuncsToEmit.empty()) 4247 EmitDeferred(); 4248 4249 // Ensure that any additions to the multiversion funcs list from either the 4250 // deferred decls or the multiversion functions themselves are emitted. 4251 if (!MultiVersionFuncs.empty()) 4252 emitMultiVersionFunctions(); 4253 } 4254 4255 void CodeGenModule::emitCPUDispatchDefinition(GlobalDecl GD) { 4256 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4257 assert(FD && "Not a FunctionDecl?"); 4258 assert(FD->isCPUDispatchMultiVersion() && "Not a multiversion function?"); 4259 const auto *DD = FD->getAttr<CPUDispatchAttr>(); 4260 assert(DD && "Not a cpu_dispatch Function?"); 4261 4262 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4263 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI); 4264 4265 StringRef ResolverName = getMangledName(GD); 4266 UpdateMultiVersionNames(GD, FD, ResolverName); 4267 4268 llvm::Type *ResolverType; 4269 GlobalDecl ResolverGD; 4270 if (getTarget().supportsIFunc()) { 4271 ResolverType = llvm::FunctionType::get( 4272 llvm::PointerType::get(DeclTy, 4273 getTypes().getTargetAddressSpace(FD->getType())), 4274 false); 4275 } 4276 else { 4277 ResolverType = DeclTy; 4278 ResolverGD = GD; 4279 } 4280 4281 auto *ResolverFunc = cast<llvm::Function>(GetOrCreateLLVMFunction( 4282 ResolverName, ResolverType, ResolverGD, /*ForVTable=*/false)); 4283 ResolverFunc->setLinkage(getMultiversionLinkage(*this, GD)); 4284 if (supportsCOMDAT()) 4285 ResolverFunc->setComdat( 4286 getModule().getOrInsertComdat(ResolverFunc->getName())); 4287 4288 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options; 4289 const TargetInfo &Target = getTarget(); 4290 unsigned Index = 0; 4291 for (const IdentifierInfo *II : DD->cpus()) { 4292 // Get the name of the target function so we can look it up/create it. 4293 std::string MangledName = getMangledNameImpl(*this, GD, FD, true) + 4294 getCPUSpecificMangling(*this, II->getName()); 4295 4296 llvm::Constant *Func = GetGlobalValue(MangledName); 4297 4298 if (!Func) { 4299 GlobalDecl ExistingDecl = Manglings.lookup(MangledName); 4300 if (ExistingDecl.getDecl() && 4301 ExistingDecl.getDecl()->getAsFunction()->isDefined()) { 4302 EmitGlobalFunctionDefinition(ExistingDecl, nullptr); 4303 Func = GetGlobalValue(MangledName); 4304 } else { 4305 if (!ExistingDecl.getDecl()) 4306 ExistingDecl = GD.getWithMultiVersionIndex(Index); 4307 4308 Func = GetOrCreateLLVMFunction( 4309 MangledName, DeclTy, ExistingDecl, 4310 /*ForVTable=*/false, /*DontDefer=*/true, 4311 /*IsThunk=*/false, llvm::AttributeList(), ForDefinition); 4312 } 4313 } 4314 4315 llvm::SmallVector<StringRef, 32> Features; 4316 Target.getCPUSpecificCPUDispatchFeatures(II->getName(), Features); 4317 llvm::transform(Features, Features.begin(), 4318 [](StringRef Str) { return Str.substr(1); }); 4319 llvm::erase_if(Features, [&Target](StringRef Feat) { 4320 return !Target.validateCpuSupports(Feat); 4321 }); 4322 Options.emplace_back(cast<llvm::Function>(Func), StringRef{}, Features); 4323 ++Index; 4324 } 4325 4326 llvm::stable_sort( 4327 Options, [](const CodeGenFunction::MultiVersionResolverOption &LHS, 4328 const CodeGenFunction::MultiVersionResolverOption &RHS) { 4329 return llvm::X86::getCpuSupportsMask(LHS.Conditions.Features) > 4330 llvm::X86::getCpuSupportsMask(RHS.Conditions.Features); 4331 }); 4332 4333 // If the list contains multiple 'default' versions, such as when it contains 4334 // 'pentium' and 'generic', don't emit the call to the generic one (since we 4335 // always run on at least a 'pentium'). We do this by deleting the 'least 4336 // advanced' (read, lowest mangling letter). 4337 while (Options.size() > 1 && 4338 llvm::all_of(llvm::X86::getCpuSupportsMask( 4339 (Options.end() - 2)->Conditions.Features), 4340 [](auto X) { return X == 0; })) { 4341 StringRef LHSName = (Options.end() - 2)->Function->getName(); 4342 StringRef RHSName = (Options.end() - 1)->Function->getName(); 4343 if (LHSName.compare(RHSName) < 0) 4344 Options.erase(Options.end() - 2); 4345 else 4346 Options.erase(Options.end() - 1); 4347 } 4348 4349 CodeGenFunction CGF(*this); 4350 CGF.EmitMultiVersionResolver(ResolverFunc, Options); 4351 4352 if (getTarget().supportsIFunc()) { 4353 llvm::GlobalValue::LinkageTypes Linkage = getMultiversionLinkage(*this, GD); 4354 auto *IFunc = cast<llvm::GlobalValue>(GetOrCreateMultiVersionResolver(GD)); 4355 4356 // Fix up function declarations that were created for cpu_specific before 4357 // cpu_dispatch was known 4358 if (!isa<llvm::GlobalIFunc>(IFunc)) { 4359 assert(cast<llvm::Function>(IFunc)->isDeclaration()); 4360 auto *GI = llvm::GlobalIFunc::create(DeclTy, 0, Linkage, "", ResolverFunc, 4361 &getModule()); 4362 GI->takeName(IFunc); 4363 IFunc->replaceAllUsesWith(GI); 4364 IFunc->eraseFromParent(); 4365 IFunc = GI; 4366 } 4367 4368 std::string AliasName = getMangledNameImpl( 4369 *this, GD, FD, /*OmitMultiVersionMangling=*/true); 4370 llvm::Constant *AliasFunc = GetGlobalValue(AliasName); 4371 if (!AliasFunc) { 4372 auto *GA = llvm::GlobalAlias::create(DeclTy, 0, Linkage, AliasName, IFunc, 4373 &getModule()); 4374 SetCommonAttributes(GD, GA); 4375 } 4376 } 4377 } 4378 4379 /// Adds a declaration to the list of multi version functions if not present. 4380 void CodeGenModule::AddDeferredMultiVersionResolverToEmit(GlobalDecl GD) { 4381 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4382 assert(FD && "Not a FunctionDecl?"); 4383 4384 if (FD->isTargetVersionMultiVersion() || FD->isTargetClonesMultiVersion()) { 4385 std::string MangledName = 4386 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true); 4387 if (!DeferredResolversToEmit.insert(MangledName).second) 4388 return; 4389 } 4390 MultiVersionFuncs.push_back(GD); 4391 } 4392 4393 /// If a dispatcher for the specified mangled name is not in the module, create 4394 /// and return an llvm Function with the specified type. 4395 llvm::Constant *CodeGenModule::GetOrCreateMultiVersionResolver(GlobalDecl GD) { 4396 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4397 assert(FD && "Not a FunctionDecl?"); 4398 4399 std::string MangledName = 4400 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true); 4401 4402 // Holds the name of the resolver, in ifunc mode this is the ifunc (which has 4403 // a separate resolver). 4404 std::string ResolverName = MangledName; 4405 if (getTarget().supportsIFunc()) { 4406 switch (FD->getMultiVersionKind()) { 4407 case MultiVersionKind::None: 4408 llvm_unreachable("unexpected MultiVersionKind::None for resolver"); 4409 case MultiVersionKind::Target: 4410 case MultiVersionKind::CPUSpecific: 4411 case MultiVersionKind::CPUDispatch: 4412 ResolverName += ".ifunc"; 4413 break; 4414 case MultiVersionKind::TargetClones: 4415 case MultiVersionKind::TargetVersion: 4416 break; 4417 } 4418 } else if (FD->isTargetMultiVersion()) { 4419 ResolverName += ".resolver"; 4420 } 4421 4422 // If the resolver has already been created, just return it. 4423 if (llvm::GlobalValue *ResolverGV = GetGlobalValue(ResolverName)) 4424 return ResolverGV; 4425 4426 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4427 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI); 4428 4429 // The resolver needs to be created. For target and target_clones, defer 4430 // creation until the end of the TU. 4431 if (FD->isTargetMultiVersion() || FD->isTargetClonesMultiVersion()) 4432 AddDeferredMultiVersionResolverToEmit(GD); 4433 4434 // For cpu_specific, don't create an ifunc yet because we don't know if the 4435 // cpu_dispatch will be emitted in this translation unit. 4436 if (getTarget().supportsIFunc() && !FD->isCPUSpecificMultiVersion()) { 4437 llvm::Type *ResolverType = llvm::FunctionType::get( 4438 llvm::PointerType::get(DeclTy, 4439 getTypes().getTargetAddressSpace(FD->getType())), 4440 false); 4441 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 4442 MangledName + ".resolver", ResolverType, GlobalDecl{}, 4443 /*ForVTable=*/false); 4444 llvm::GlobalIFunc *GIF = 4445 llvm::GlobalIFunc::create(DeclTy, 0, getMultiversionLinkage(*this, GD), 4446 "", Resolver, &getModule()); 4447 GIF->setName(ResolverName); 4448 SetCommonAttributes(FD, GIF); 4449 4450 return GIF; 4451 } 4452 4453 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 4454 ResolverName, DeclTy, GlobalDecl{}, /*ForVTable=*/false); 4455 assert(isa<llvm::GlobalValue>(Resolver) && 4456 "Resolver should be created for the first time"); 4457 SetCommonAttributes(FD, cast<llvm::GlobalValue>(Resolver)); 4458 return Resolver; 4459 } 4460 4461 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the 4462 /// module, create and return an llvm Function with the specified type. If there 4463 /// is something in the module with the specified name, return it potentially 4464 /// bitcasted to the right type. 4465 /// 4466 /// If D is non-null, it specifies a decl that correspond to this. This is used 4467 /// to set the attributes on the function when it is first created. 4468 llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction( 4469 StringRef MangledName, llvm::Type *Ty, GlobalDecl GD, bool ForVTable, 4470 bool DontDefer, bool IsThunk, llvm::AttributeList ExtraAttrs, 4471 ForDefinition_t IsForDefinition) { 4472 const Decl *D = GD.getDecl(); 4473 4474 // Any attempts to use a MultiVersion function should result in retrieving 4475 // the iFunc instead. Name Mangling will handle the rest of the changes. 4476 if (const FunctionDecl *FD = cast_or_null<FunctionDecl>(D)) { 4477 // For the device mark the function as one that should be emitted. 4478 if (getLangOpts().OpenMPIsTargetDevice && OpenMPRuntime && 4479 !OpenMPRuntime->markAsGlobalTarget(GD) && FD->isDefined() && 4480 !DontDefer && !IsForDefinition) { 4481 if (const FunctionDecl *FDDef = FD->getDefinition()) { 4482 GlobalDecl GDDef; 4483 if (const auto *CD = dyn_cast<CXXConstructorDecl>(FDDef)) 4484 GDDef = GlobalDecl(CD, GD.getCtorType()); 4485 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(FDDef)) 4486 GDDef = GlobalDecl(DD, GD.getDtorType()); 4487 else 4488 GDDef = GlobalDecl(FDDef); 4489 EmitGlobal(GDDef); 4490 } 4491 } 4492 4493 if (FD->isMultiVersion()) { 4494 UpdateMultiVersionNames(GD, FD, MangledName); 4495 if (FD->getASTContext().getTargetInfo().getTriple().isAArch64() && 4496 !FD->isUsed()) 4497 AddDeferredMultiVersionResolverToEmit(GD); 4498 else if (!IsForDefinition) 4499 return GetOrCreateMultiVersionResolver(GD); 4500 } 4501 } 4502 4503 // Lookup the entry, lazily creating it if necessary. 4504 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 4505 if (Entry) { 4506 if (WeakRefReferences.erase(Entry)) { 4507 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D); 4508 if (FD && !FD->hasAttr<WeakAttr>()) 4509 Entry->setLinkage(llvm::Function::ExternalLinkage); 4510 } 4511 4512 // Handle dropped DLL attributes. 4513 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() && 4514 !shouldMapVisibilityToDLLExport(cast_or_null<NamedDecl>(D))) { 4515 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass); 4516 setDSOLocal(Entry); 4517 } 4518 4519 // If there are two attempts to define the same mangled name, issue an 4520 // error. 4521 if (IsForDefinition && !Entry->isDeclaration()) { 4522 GlobalDecl OtherGD; 4523 // Check that GD is not yet in DiagnosedConflictingDefinitions is required 4524 // to make sure that we issue an error only once. 4525 if (lookupRepresentativeDecl(MangledName, OtherGD) && 4526 (GD.getCanonicalDecl().getDecl() != 4527 OtherGD.getCanonicalDecl().getDecl()) && 4528 DiagnosedConflictingDefinitions.insert(GD).second) { 4529 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name) 4530 << MangledName; 4531 getDiags().Report(OtherGD.getDecl()->getLocation(), 4532 diag::note_previous_definition); 4533 } 4534 } 4535 4536 if ((isa<llvm::Function>(Entry) || isa<llvm::GlobalAlias>(Entry)) && 4537 (Entry->getValueType() == Ty)) { 4538 return Entry; 4539 } 4540 4541 // Make sure the result is of the correct type. 4542 // (If function is requested for a definition, we always need to create a new 4543 // function, not just return a bitcast.) 4544 if (!IsForDefinition) 4545 return Entry; 4546 } 4547 4548 // This function doesn't have a complete type (for example, the return 4549 // type is an incomplete struct). Use a fake type instead, and make 4550 // sure not to try to set attributes. 4551 bool IsIncompleteFunction = false; 4552 4553 llvm::FunctionType *FTy; 4554 if (isa<llvm::FunctionType>(Ty)) { 4555 FTy = cast<llvm::FunctionType>(Ty); 4556 } else { 4557 FTy = llvm::FunctionType::get(VoidTy, false); 4558 IsIncompleteFunction = true; 4559 } 4560 4561 llvm::Function *F = 4562 llvm::Function::Create(FTy, llvm::Function::ExternalLinkage, 4563 Entry ? StringRef() : MangledName, &getModule()); 4564 4565 // Store the declaration associated with this function so it is potentially 4566 // updated by further declarations or definitions and emitted at the end. 4567 if (D && D->hasAttr<AnnotateAttr>()) 4568 DeferredAnnotations[MangledName] = cast<ValueDecl>(D); 4569 4570 // If we already created a function with the same mangled name (but different 4571 // type) before, take its name and add it to the list of functions to be 4572 // replaced with F at the end of CodeGen. 4573 // 4574 // This happens if there is a prototype for a function (e.g. "int f()") and 4575 // then a definition of a different type (e.g. "int f(int x)"). 4576 if (Entry) { 4577 F->takeName(Entry); 4578 4579 // This might be an implementation of a function without a prototype, in 4580 // which case, try to do special replacement of calls which match the new 4581 // prototype. The really key thing here is that we also potentially drop 4582 // arguments from the call site so as to make a direct call, which makes the 4583 // inliner happier and suppresses a number of optimizer warnings (!) about 4584 // dropping arguments. 4585 if (!Entry->use_empty()) { 4586 ReplaceUsesOfNonProtoTypeWithRealFunction(Entry, F); 4587 Entry->removeDeadConstantUsers(); 4588 } 4589 4590 addGlobalValReplacement(Entry, F); 4591 } 4592 4593 assert(F->getName() == MangledName && "name was uniqued!"); 4594 if (D) 4595 SetFunctionAttributes(GD, F, IsIncompleteFunction, IsThunk); 4596 if (ExtraAttrs.hasFnAttrs()) { 4597 llvm::AttrBuilder B(F->getContext(), ExtraAttrs.getFnAttrs()); 4598 F->addFnAttrs(B); 4599 } 4600 4601 if (!DontDefer) { 4602 // All MSVC dtors other than the base dtor are linkonce_odr and delegate to 4603 // each other bottoming out with the base dtor. Therefore we emit non-base 4604 // dtors on usage, even if there is no dtor definition in the TU. 4605 if (isa_and_nonnull<CXXDestructorDecl>(D) && 4606 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D), 4607 GD.getDtorType())) 4608 addDeferredDeclToEmit(GD); 4609 4610 // This is the first use or definition of a mangled name. If there is a 4611 // deferred decl with this name, remember that we need to emit it at the end 4612 // of the file. 4613 auto DDI = DeferredDecls.find(MangledName); 4614 if (DDI != DeferredDecls.end()) { 4615 // Move the potentially referenced deferred decl to the 4616 // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we 4617 // don't need it anymore). 4618 addDeferredDeclToEmit(DDI->second); 4619 DeferredDecls.erase(DDI); 4620 4621 // Otherwise, there are cases we have to worry about where we're 4622 // using a declaration for which we must emit a definition but where 4623 // we might not find a top-level definition: 4624 // - member functions defined inline in their classes 4625 // - friend functions defined inline in some class 4626 // - special member functions with implicit definitions 4627 // If we ever change our AST traversal to walk into class methods, 4628 // this will be unnecessary. 4629 // 4630 // We also don't emit a definition for a function if it's going to be an 4631 // entry in a vtable, unless it's already marked as used. 4632 } else if (getLangOpts().CPlusPlus && D) { 4633 // Look for a declaration that's lexically in a record. 4634 for (const auto *FD = cast<FunctionDecl>(D)->getMostRecentDecl(); FD; 4635 FD = FD->getPreviousDecl()) { 4636 if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) { 4637 if (FD->doesThisDeclarationHaveABody()) { 4638 addDeferredDeclToEmit(GD.getWithDecl(FD)); 4639 break; 4640 } 4641 } 4642 } 4643 } 4644 } 4645 4646 // Make sure the result is of the requested type. 4647 if (!IsIncompleteFunction) { 4648 assert(F->getFunctionType() == Ty); 4649 return F; 4650 } 4651 4652 return F; 4653 } 4654 4655 /// GetAddrOfFunction - Return the address of the given function. If Ty is 4656 /// non-null, then this function will use the specified type if it has to 4657 /// create it (this occurs when we see a definition of the function). 4658 llvm::Constant * 4659 CodeGenModule::GetAddrOfFunction(GlobalDecl GD, llvm::Type *Ty, bool ForVTable, 4660 bool DontDefer, 4661 ForDefinition_t IsForDefinition) { 4662 // If there was no specific requested type, just convert it now. 4663 if (!Ty) { 4664 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4665 Ty = getTypes().ConvertType(FD->getType()); 4666 } 4667 4668 // Devirtualized destructor calls may come through here instead of via 4669 // getAddrOfCXXStructor. Make sure we use the MS ABI base destructor instead 4670 // of the complete destructor when necessary. 4671 if (const auto *DD = dyn_cast<CXXDestructorDecl>(GD.getDecl())) { 4672 if (getTarget().getCXXABI().isMicrosoft() && 4673 GD.getDtorType() == Dtor_Complete && 4674 DD->getParent()->getNumVBases() == 0) 4675 GD = GlobalDecl(DD, Dtor_Base); 4676 } 4677 4678 StringRef MangledName = getMangledName(GD); 4679 auto *F = GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable, DontDefer, 4680 /*IsThunk=*/false, llvm::AttributeList(), 4681 IsForDefinition); 4682 // Returns kernel handle for HIP kernel stub function. 4683 if (LangOpts.CUDA && !LangOpts.CUDAIsDevice && 4684 cast<FunctionDecl>(GD.getDecl())->hasAttr<CUDAGlobalAttr>()) { 4685 auto *Handle = getCUDARuntime().getKernelHandle( 4686 cast<llvm::Function>(F->stripPointerCasts()), GD); 4687 if (IsForDefinition) 4688 return F; 4689 return Handle; 4690 } 4691 return F; 4692 } 4693 4694 llvm::Constant *CodeGenModule::GetFunctionStart(const ValueDecl *Decl) { 4695 llvm::GlobalValue *F = 4696 cast<llvm::GlobalValue>(GetAddrOfFunction(Decl)->stripPointerCasts()); 4697 4698 return llvm::NoCFIValue::get(F); 4699 } 4700 4701 static const FunctionDecl * 4702 GetRuntimeFunctionDecl(ASTContext &C, StringRef Name) { 4703 TranslationUnitDecl *TUDecl = C.getTranslationUnitDecl(); 4704 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); 4705 4706 IdentifierInfo &CII = C.Idents.get(Name); 4707 for (const auto *Result : DC->lookup(&CII)) 4708 if (const auto *FD = dyn_cast<FunctionDecl>(Result)) 4709 return FD; 4710 4711 if (!C.getLangOpts().CPlusPlus) 4712 return nullptr; 4713 4714 // Demangle the premangled name from getTerminateFn() 4715 IdentifierInfo &CXXII = 4716 (Name == "_ZSt9terminatev" || Name == "?terminate@@YAXXZ") 4717 ? C.Idents.get("terminate") 4718 : C.Idents.get(Name); 4719 4720 for (const auto &N : {"__cxxabiv1", "std"}) { 4721 IdentifierInfo &NS = C.Idents.get(N); 4722 for (const auto *Result : DC->lookup(&NS)) { 4723 const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(Result); 4724 if (auto *LSD = dyn_cast<LinkageSpecDecl>(Result)) 4725 for (const auto *Result : LSD->lookup(&NS)) 4726 if ((ND = dyn_cast<NamespaceDecl>(Result))) 4727 break; 4728 4729 if (ND) 4730 for (const auto *Result : ND->lookup(&CXXII)) 4731 if (const auto *FD = dyn_cast<FunctionDecl>(Result)) 4732 return FD; 4733 } 4734 } 4735 4736 return nullptr; 4737 } 4738 4739 /// CreateRuntimeFunction - Create a new runtime function with the specified 4740 /// type and name. 4741 llvm::FunctionCallee 4742 CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy, StringRef Name, 4743 llvm::AttributeList ExtraAttrs, bool Local, 4744 bool AssumeConvergent) { 4745 if (AssumeConvergent) { 4746 ExtraAttrs = 4747 ExtraAttrs.addFnAttribute(VMContext, llvm::Attribute::Convergent); 4748 } 4749 4750 llvm::Constant *C = 4751 GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false, 4752 /*DontDefer=*/false, /*IsThunk=*/false, 4753 ExtraAttrs); 4754 4755 if (auto *F = dyn_cast<llvm::Function>(C)) { 4756 if (F->empty()) { 4757 F->setCallingConv(getRuntimeCC()); 4758 4759 // In Windows Itanium environments, try to mark runtime functions 4760 // dllimport. For Mingw and MSVC, don't. We don't really know if the user 4761 // will link their standard library statically or dynamically. Marking 4762 // functions imported when they are not imported can cause linker errors 4763 // and warnings. 4764 if (!Local && getTriple().isWindowsItaniumEnvironment() && 4765 !getCodeGenOpts().LTOVisibilityPublicStd) { 4766 const FunctionDecl *FD = GetRuntimeFunctionDecl(Context, Name); 4767 if (!FD || FD->hasAttr<DLLImportAttr>()) { 4768 F->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass); 4769 F->setLinkage(llvm::GlobalValue::ExternalLinkage); 4770 } 4771 } 4772 setDSOLocal(F); 4773 } 4774 } 4775 4776 return {FTy, C}; 4777 } 4778 4779 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module, 4780 /// create and return an llvm GlobalVariable with the specified type and address 4781 /// space. If there is something in the module with the specified name, return 4782 /// it potentially bitcasted to the right type. 4783 /// 4784 /// If D is non-null, it specifies a decl that correspond to this. This is used 4785 /// to set the attributes on the global when it is first created. 4786 /// 4787 /// If IsForDefinition is true, it is guaranteed that an actual global with 4788 /// type Ty will be returned, not conversion of a variable with the same 4789 /// mangled name but some other type. 4790 llvm::Constant * 4791 CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty, 4792 LangAS AddrSpace, const VarDecl *D, 4793 ForDefinition_t IsForDefinition) { 4794 // Lookup the entry, lazily creating it if necessary. 4795 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 4796 unsigned TargetAS = getContext().getTargetAddressSpace(AddrSpace); 4797 if (Entry) { 4798 if (WeakRefReferences.erase(Entry)) { 4799 if (D && !D->hasAttr<WeakAttr>()) 4800 Entry->setLinkage(llvm::Function::ExternalLinkage); 4801 } 4802 4803 // Handle dropped DLL attributes. 4804 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() && 4805 !shouldMapVisibilityToDLLExport(D)) 4806 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass); 4807 4808 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd && D) 4809 getOpenMPRuntime().registerTargetGlobalVariable(D, Entry); 4810 4811 if (Entry->getValueType() == Ty && Entry->getAddressSpace() == TargetAS) 4812 return Entry; 4813 4814 // If there are two attempts to define the same mangled name, issue an 4815 // error. 4816 if (IsForDefinition && !Entry->isDeclaration()) { 4817 GlobalDecl OtherGD; 4818 const VarDecl *OtherD; 4819 4820 // Check that D is not yet in DiagnosedConflictingDefinitions is required 4821 // to make sure that we issue an error only once. 4822 if (D && lookupRepresentativeDecl(MangledName, OtherGD) && 4823 (D->getCanonicalDecl() != OtherGD.getCanonicalDecl().getDecl()) && 4824 (OtherD = dyn_cast<VarDecl>(OtherGD.getDecl())) && 4825 OtherD->hasInit() && 4826 DiagnosedConflictingDefinitions.insert(D).second) { 4827 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name) 4828 << MangledName; 4829 getDiags().Report(OtherGD.getDecl()->getLocation(), 4830 diag::note_previous_definition); 4831 } 4832 } 4833 4834 // Make sure the result is of the correct type. 4835 if (Entry->getType()->getAddressSpace() != TargetAS) 4836 return llvm::ConstantExpr::getAddrSpaceCast( 4837 Entry, llvm::PointerType::get(Ty->getContext(), TargetAS)); 4838 4839 // (If global is requested for a definition, we always need to create a new 4840 // global, not just return a bitcast.) 4841 if (!IsForDefinition) 4842 return Entry; 4843 } 4844 4845 auto DAddrSpace = GetGlobalVarAddressSpace(D); 4846 4847 auto *GV = new llvm::GlobalVariable( 4848 getModule(), Ty, false, llvm::GlobalValue::ExternalLinkage, nullptr, 4849 MangledName, nullptr, llvm::GlobalVariable::NotThreadLocal, 4850 getContext().getTargetAddressSpace(DAddrSpace)); 4851 4852 // If we already created a global with the same mangled name (but different 4853 // type) before, take its name and remove it from its parent. 4854 if (Entry) { 4855 GV->takeName(Entry); 4856 4857 if (!Entry->use_empty()) { 4858 Entry->replaceAllUsesWith(GV); 4859 } 4860 4861 Entry->eraseFromParent(); 4862 } 4863 4864 // This is the first use or definition of a mangled name. If there is a 4865 // deferred decl with this name, remember that we need to emit it at the end 4866 // of the file. 4867 auto DDI = DeferredDecls.find(MangledName); 4868 if (DDI != DeferredDecls.end()) { 4869 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 4870 // list, and remove it from DeferredDecls (since we don't need it anymore). 4871 addDeferredDeclToEmit(DDI->second); 4872 DeferredDecls.erase(DDI); 4873 } 4874 4875 // Handle things which are present even on external declarations. 4876 if (D) { 4877 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd) 4878 getOpenMPRuntime().registerTargetGlobalVariable(D, GV); 4879 4880 // FIXME: This code is overly simple and should be merged with other global 4881 // handling. 4882 GV->setConstant(D->getType().isConstantStorage(getContext(), false, false)); 4883 4884 GV->setAlignment(getContext().getDeclAlign(D).getAsAlign()); 4885 4886 setLinkageForGV(GV, D); 4887 4888 if (D->getTLSKind()) { 4889 if (D->getTLSKind() == VarDecl::TLS_Dynamic) 4890 CXXThreadLocals.push_back(D); 4891 setTLSMode(GV, *D); 4892 } 4893 4894 setGVProperties(GV, D); 4895 4896 // If required by the ABI, treat declarations of static data members with 4897 // inline initializers as definitions. 4898 if (getContext().isMSStaticDataMemberInlineDefinition(D)) { 4899 EmitGlobalVarDefinition(D); 4900 } 4901 4902 // Emit section information for extern variables. 4903 if (D->hasExternalStorage()) { 4904 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) 4905 GV->setSection(SA->getName()); 4906 } 4907 4908 // Handle XCore specific ABI requirements. 4909 if (getTriple().getArch() == llvm::Triple::xcore && 4910 D->getLanguageLinkage() == CLanguageLinkage && 4911 D->getType().isConstant(Context) && 4912 isExternallyVisible(D->getLinkageAndVisibility().getLinkage())) 4913 GV->setSection(".cp.rodata"); 4914 4915 // Handle code model attribute 4916 if (const auto *CMA = D->getAttr<CodeModelAttr>()) 4917 GV->setCodeModel(CMA->getModel()); 4918 4919 // Check if we a have a const declaration with an initializer, we may be 4920 // able to emit it as available_externally to expose it's value to the 4921 // optimizer. 4922 if (Context.getLangOpts().CPlusPlus && GV->hasExternalLinkage() && 4923 D->getType().isConstQualified() && !GV->hasInitializer() && 4924 !D->hasDefinition() && D->hasInit() && !D->hasAttr<DLLImportAttr>()) { 4925 const auto *Record = 4926 Context.getBaseElementType(D->getType())->getAsCXXRecordDecl(); 4927 bool HasMutableFields = Record && Record->hasMutableFields(); 4928 if (!HasMutableFields) { 4929 const VarDecl *InitDecl; 4930 const Expr *InitExpr = D->getAnyInitializer(InitDecl); 4931 if (InitExpr) { 4932 ConstantEmitter emitter(*this); 4933 llvm::Constant *Init = emitter.tryEmitForInitializer(*InitDecl); 4934 if (Init) { 4935 auto *InitType = Init->getType(); 4936 if (GV->getValueType() != InitType) { 4937 // The type of the initializer does not match the definition. 4938 // This happens when an initializer has a different type from 4939 // the type of the global (because of padding at the end of a 4940 // structure for instance). 4941 GV->setName(StringRef()); 4942 // Make a new global with the correct type, this is now guaranteed 4943 // to work. 4944 auto *NewGV = cast<llvm::GlobalVariable>( 4945 GetAddrOfGlobalVar(D, InitType, IsForDefinition) 4946 ->stripPointerCasts()); 4947 4948 // Erase the old global, since it is no longer used. 4949 GV->eraseFromParent(); 4950 GV = NewGV; 4951 } else { 4952 GV->setInitializer(Init); 4953 GV->setConstant(true); 4954 GV->setLinkage(llvm::GlobalValue::AvailableExternallyLinkage); 4955 } 4956 emitter.finalize(GV); 4957 } 4958 } 4959 } 4960 } 4961 } 4962 4963 if (D && 4964 D->isThisDeclarationADefinition(Context) == VarDecl::DeclarationOnly) { 4965 getTargetCodeGenInfo().setTargetAttributes(D, GV, *this); 4966 // External HIP managed variables needed to be recorded for transformation 4967 // in both device and host compilations. 4968 if (getLangOpts().CUDA && D && D->hasAttr<HIPManagedAttr>() && 4969 D->hasExternalStorage()) 4970 getCUDARuntime().handleVarRegistration(D, *GV); 4971 } 4972 4973 if (D) 4974 SanitizerMD->reportGlobal(GV, *D); 4975 4976 LangAS ExpectedAS = 4977 D ? D->getType().getAddressSpace() 4978 : (LangOpts.OpenCL ? LangAS::opencl_global : LangAS::Default); 4979 assert(getContext().getTargetAddressSpace(ExpectedAS) == TargetAS); 4980 if (DAddrSpace != ExpectedAS) { 4981 return getTargetCodeGenInfo().performAddrSpaceCast( 4982 *this, GV, DAddrSpace, ExpectedAS, 4983 llvm::PointerType::get(getLLVMContext(), TargetAS)); 4984 } 4985 4986 return GV; 4987 } 4988 4989 llvm::Constant * 4990 CodeGenModule::GetAddrOfGlobal(GlobalDecl GD, ForDefinition_t IsForDefinition) { 4991 const Decl *D = GD.getDecl(); 4992 4993 if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D)) 4994 return getAddrOfCXXStructor(GD, /*FnInfo=*/nullptr, /*FnType=*/nullptr, 4995 /*DontDefer=*/false, IsForDefinition); 4996 4997 if (isa<CXXMethodDecl>(D)) { 4998 auto FInfo = 4999 &getTypes().arrangeCXXMethodDeclaration(cast<CXXMethodDecl>(D)); 5000 auto Ty = getTypes().GetFunctionType(*FInfo); 5001 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false, 5002 IsForDefinition); 5003 } 5004 5005 if (isa<FunctionDecl>(D)) { 5006 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 5007 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 5008 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false, 5009 IsForDefinition); 5010 } 5011 5012 return GetAddrOfGlobalVar(cast<VarDecl>(D), /*Ty=*/nullptr, IsForDefinition); 5013 } 5014 5015 llvm::GlobalVariable *CodeGenModule::CreateOrReplaceCXXRuntimeVariable( 5016 StringRef Name, llvm::Type *Ty, llvm::GlobalValue::LinkageTypes Linkage, 5017 llvm::Align Alignment) { 5018 llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name); 5019 llvm::GlobalVariable *OldGV = nullptr; 5020 5021 if (GV) { 5022 // Check if the variable has the right type. 5023 if (GV->getValueType() == Ty) 5024 return GV; 5025 5026 // Because C++ name mangling, the only way we can end up with an already 5027 // existing global with the same name is if it has been declared extern "C". 5028 assert(GV->isDeclaration() && "Declaration has wrong type!"); 5029 OldGV = GV; 5030 } 5031 5032 // Create a new variable. 5033 GV = new llvm::GlobalVariable(getModule(), Ty, /*isConstant=*/true, 5034 Linkage, nullptr, Name); 5035 5036 if (OldGV) { 5037 // Replace occurrences of the old variable if needed. 5038 GV->takeName(OldGV); 5039 5040 if (!OldGV->use_empty()) { 5041 OldGV->replaceAllUsesWith(GV); 5042 } 5043 5044 OldGV->eraseFromParent(); 5045 } 5046 5047 if (supportsCOMDAT() && GV->isWeakForLinker() && 5048 !GV->hasAvailableExternallyLinkage()) 5049 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 5050 5051 GV->setAlignment(Alignment); 5052 5053 return GV; 5054 } 5055 5056 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the 5057 /// given global variable. If Ty is non-null and if the global doesn't exist, 5058 /// then it will be created with the specified type instead of whatever the 5059 /// normal requested type would be. If IsForDefinition is true, it is guaranteed 5060 /// that an actual global with type Ty will be returned, not conversion of a 5061 /// variable with the same mangled name but some other type. 5062 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D, 5063 llvm::Type *Ty, 5064 ForDefinition_t IsForDefinition) { 5065 assert(D->hasGlobalStorage() && "Not a global variable"); 5066 QualType ASTTy = D->getType(); 5067 if (!Ty) 5068 Ty = getTypes().ConvertTypeForMem(ASTTy); 5069 5070 StringRef MangledName = getMangledName(D); 5071 return GetOrCreateLLVMGlobal(MangledName, Ty, ASTTy.getAddressSpace(), D, 5072 IsForDefinition); 5073 } 5074 5075 /// CreateRuntimeVariable - Create a new runtime global variable with the 5076 /// specified type and name. 5077 llvm::Constant * 5078 CodeGenModule::CreateRuntimeVariable(llvm::Type *Ty, 5079 StringRef Name) { 5080 LangAS AddrSpace = getContext().getLangOpts().OpenCL ? LangAS::opencl_global 5081 : LangAS::Default; 5082 auto *Ret = GetOrCreateLLVMGlobal(Name, Ty, AddrSpace, nullptr); 5083 setDSOLocal(cast<llvm::GlobalValue>(Ret->stripPointerCasts())); 5084 return Ret; 5085 } 5086 5087 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) { 5088 assert(!D->getInit() && "Cannot emit definite definitions here!"); 5089 5090 StringRef MangledName = getMangledName(D); 5091 llvm::GlobalValue *GV = GetGlobalValue(MangledName); 5092 5093 // We already have a definition, not declaration, with the same mangled name. 5094 // Emitting of declaration is not required (and actually overwrites emitted 5095 // definition). 5096 if (GV && !GV->isDeclaration()) 5097 return; 5098 5099 // If we have not seen a reference to this variable yet, place it into the 5100 // deferred declarations table to be emitted if needed later. 5101 if (!MustBeEmitted(D) && !GV) { 5102 DeferredDecls[MangledName] = D; 5103 return; 5104 } 5105 5106 // The tentative definition is the only definition. 5107 EmitGlobalVarDefinition(D); 5108 } 5109 5110 void CodeGenModule::EmitExternalDeclaration(const VarDecl *D) { 5111 EmitExternalVarDeclaration(D); 5112 } 5113 5114 CharUnits CodeGenModule::GetTargetTypeStoreSize(llvm::Type *Ty) const { 5115 return Context.toCharUnitsFromBits( 5116 getDataLayout().getTypeStoreSizeInBits(Ty)); 5117 } 5118 5119 LangAS CodeGenModule::GetGlobalVarAddressSpace(const VarDecl *D) { 5120 if (LangOpts.OpenCL) { 5121 LangAS AS = D ? D->getType().getAddressSpace() : LangAS::opencl_global; 5122 assert(AS == LangAS::opencl_global || 5123 AS == LangAS::opencl_global_device || 5124 AS == LangAS::opencl_global_host || 5125 AS == LangAS::opencl_constant || 5126 AS == LangAS::opencl_local || 5127 AS >= LangAS::FirstTargetAddressSpace); 5128 return AS; 5129 } 5130 5131 if (LangOpts.SYCLIsDevice && 5132 (!D || D->getType().getAddressSpace() == LangAS::Default)) 5133 return LangAS::sycl_global; 5134 5135 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) { 5136 if (D) { 5137 if (D->hasAttr<CUDAConstantAttr>()) 5138 return LangAS::cuda_constant; 5139 if (D->hasAttr<CUDASharedAttr>()) 5140 return LangAS::cuda_shared; 5141 if (D->hasAttr<CUDADeviceAttr>()) 5142 return LangAS::cuda_device; 5143 if (D->getType().isConstQualified()) 5144 return LangAS::cuda_constant; 5145 } 5146 return LangAS::cuda_device; 5147 } 5148 5149 if (LangOpts.OpenMP) { 5150 LangAS AS; 5151 if (OpenMPRuntime->hasAllocateAttributeForGlobalVar(D, AS)) 5152 return AS; 5153 } 5154 return getTargetCodeGenInfo().getGlobalVarAddressSpace(*this, D); 5155 } 5156 5157 LangAS CodeGenModule::GetGlobalConstantAddressSpace() const { 5158 // OpenCL v1.2 s6.5.3: a string literal is in the constant address space. 5159 if (LangOpts.OpenCL) 5160 return LangAS::opencl_constant; 5161 if (LangOpts.SYCLIsDevice) 5162 return LangAS::sycl_global; 5163 if (LangOpts.HIP && LangOpts.CUDAIsDevice && getTriple().isSPIRV()) 5164 // For HIPSPV map literals to cuda_device (maps to CrossWorkGroup in SPIR-V) 5165 // instead of default AS (maps to Generic in SPIR-V). Otherwise, we end up 5166 // with OpVariable instructions with Generic storage class which is not 5167 // allowed (SPIR-V V1.6 s3.42.8). Also, mapping literals to SPIR-V 5168 // UniformConstant storage class is not viable as pointers to it may not be 5169 // casted to Generic pointers which are used to model HIP's "flat" pointers. 5170 return LangAS::cuda_device; 5171 if (auto AS = getTarget().getConstantAddressSpace()) 5172 return *AS; 5173 return LangAS::Default; 5174 } 5175 5176 // In address space agnostic languages, string literals are in default address 5177 // space in AST. However, certain targets (e.g. amdgcn) request them to be 5178 // emitted in constant address space in LLVM IR. To be consistent with other 5179 // parts of AST, string literal global variables in constant address space 5180 // need to be casted to default address space before being put into address 5181 // map and referenced by other part of CodeGen. 5182 // In OpenCL, string literals are in constant address space in AST, therefore 5183 // they should not be casted to default address space. 5184 static llvm::Constant * 5185 castStringLiteralToDefaultAddressSpace(CodeGenModule &CGM, 5186 llvm::GlobalVariable *GV) { 5187 llvm::Constant *Cast = GV; 5188 if (!CGM.getLangOpts().OpenCL) { 5189 auto AS = CGM.GetGlobalConstantAddressSpace(); 5190 if (AS != LangAS::Default) 5191 Cast = CGM.getTargetCodeGenInfo().performAddrSpaceCast( 5192 CGM, GV, AS, LangAS::Default, 5193 llvm::PointerType::get( 5194 CGM.getLLVMContext(), 5195 CGM.getContext().getTargetAddressSpace(LangAS::Default))); 5196 } 5197 return Cast; 5198 } 5199 5200 template<typename SomeDecl> 5201 void CodeGenModule::MaybeHandleStaticInExternC(const SomeDecl *D, 5202 llvm::GlobalValue *GV) { 5203 if (!getLangOpts().CPlusPlus) 5204 return; 5205 5206 // Must have 'used' attribute, or else inline assembly can't rely on 5207 // the name existing. 5208 if (!D->template hasAttr<UsedAttr>()) 5209 return; 5210 5211 // Must have internal linkage and an ordinary name. 5212 if (!D->getIdentifier() || D->getFormalLinkage() != Linkage::Internal) 5213 return; 5214 5215 // Must be in an extern "C" context. Entities declared directly within 5216 // a record are not extern "C" even if the record is in such a context. 5217 const SomeDecl *First = D->getFirstDecl(); 5218 if (First->getDeclContext()->isRecord() || !First->isInExternCContext()) 5219 return; 5220 5221 // OK, this is an internal linkage entity inside an extern "C" linkage 5222 // specification. Make a note of that so we can give it the "expected" 5223 // mangled name if nothing else is using that name. 5224 std::pair<StaticExternCMap::iterator, bool> R = 5225 StaticExternCValues.insert(std::make_pair(D->getIdentifier(), GV)); 5226 5227 // If we have multiple internal linkage entities with the same name 5228 // in extern "C" regions, none of them gets that name. 5229 if (!R.second) 5230 R.first->second = nullptr; 5231 } 5232 5233 static bool shouldBeInCOMDAT(CodeGenModule &CGM, const Decl &D) { 5234 if (!CGM.supportsCOMDAT()) 5235 return false; 5236 5237 if (D.hasAttr<SelectAnyAttr>()) 5238 return true; 5239 5240 GVALinkage Linkage; 5241 if (auto *VD = dyn_cast<VarDecl>(&D)) 5242 Linkage = CGM.getContext().GetGVALinkageForVariable(VD); 5243 else 5244 Linkage = CGM.getContext().GetGVALinkageForFunction(cast<FunctionDecl>(&D)); 5245 5246 switch (Linkage) { 5247 case GVA_Internal: 5248 case GVA_AvailableExternally: 5249 case GVA_StrongExternal: 5250 return false; 5251 case GVA_DiscardableODR: 5252 case GVA_StrongODR: 5253 return true; 5254 } 5255 llvm_unreachable("No such linkage"); 5256 } 5257 5258 bool CodeGenModule::supportsCOMDAT() const { 5259 return getTriple().supportsCOMDAT(); 5260 } 5261 5262 void CodeGenModule::maybeSetTrivialComdat(const Decl &D, 5263 llvm::GlobalObject &GO) { 5264 if (!shouldBeInCOMDAT(*this, D)) 5265 return; 5266 GO.setComdat(TheModule.getOrInsertComdat(GO.getName())); 5267 } 5268 5269 /// Pass IsTentative as true if you want to create a tentative definition. 5270 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D, 5271 bool IsTentative) { 5272 // OpenCL global variables of sampler type are translated to function calls, 5273 // therefore no need to be translated. 5274 QualType ASTTy = D->getType(); 5275 if (getLangOpts().OpenCL && ASTTy->isSamplerT()) 5276 return; 5277 5278 // If this is OpenMP device, check if it is legal to emit this global 5279 // normally. 5280 if (LangOpts.OpenMPIsTargetDevice && OpenMPRuntime && 5281 OpenMPRuntime->emitTargetGlobalVariable(D)) 5282 return; 5283 5284 llvm::TrackingVH<llvm::Constant> Init; 5285 bool NeedsGlobalCtor = false; 5286 // Whether the definition of the variable is available externally. 5287 // If yes, we shouldn't emit the GloablCtor and GlobalDtor for the variable 5288 // since this is the job for its original source. 5289 bool IsDefinitionAvailableExternally = 5290 getContext().GetGVALinkageForVariable(D) == GVA_AvailableExternally; 5291 bool NeedsGlobalDtor = 5292 !IsDefinitionAvailableExternally && 5293 D->needsDestruction(getContext()) == QualType::DK_cxx_destructor; 5294 5295 const VarDecl *InitDecl; 5296 const Expr *InitExpr = D->getAnyInitializer(InitDecl); 5297 5298 std::optional<ConstantEmitter> emitter; 5299 5300 // CUDA E.2.4.1 "__shared__ variables cannot have an initialization 5301 // as part of their declaration." Sema has already checked for 5302 // error cases, so we just need to set Init to UndefValue. 5303 bool IsCUDASharedVar = 5304 getLangOpts().CUDAIsDevice && D->hasAttr<CUDASharedAttr>(); 5305 // Shadows of initialized device-side global variables are also left 5306 // undefined. 5307 // Managed Variables should be initialized on both host side and device side. 5308 bool IsCUDAShadowVar = 5309 !getLangOpts().CUDAIsDevice && !D->hasAttr<HIPManagedAttr>() && 5310 (D->hasAttr<CUDAConstantAttr>() || D->hasAttr<CUDADeviceAttr>() || 5311 D->hasAttr<CUDASharedAttr>()); 5312 bool IsCUDADeviceShadowVar = 5313 getLangOpts().CUDAIsDevice && !D->hasAttr<HIPManagedAttr>() && 5314 (D->getType()->isCUDADeviceBuiltinSurfaceType() || 5315 D->getType()->isCUDADeviceBuiltinTextureType()); 5316 if (getLangOpts().CUDA && 5317 (IsCUDASharedVar || IsCUDAShadowVar || IsCUDADeviceShadowVar)) 5318 Init = llvm::UndefValue::get(getTypes().ConvertTypeForMem(ASTTy)); 5319 else if (D->hasAttr<LoaderUninitializedAttr>()) 5320 Init = llvm::UndefValue::get(getTypes().ConvertTypeForMem(ASTTy)); 5321 else if (!InitExpr) { 5322 // This is a tentative definition; tentative definitions are 5323 // implicitly initialized with { 0 }. 5324 // 5325 // Note that tentative definitions are only emitted at the end of 5326 // a translation unit, so they should never have incomplete 5327 // type. In addition, EmitTentativeDefinition makes sure that we 5328 // never attempt to emit a tentative definition if a real one 5329 // exists. A use may still exists, however, so we still may need 5330 // to do a RAUW. 5331 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type"); 5332 Init = EmitNullConstant(D->getType()); 5333 } else { 5334 initializedGlobalDecl = GlobalDecl(D); 5335 emitter.emplace(*this); 5336 llvm::Constant *Initializer = emitter->tryEmitForInitializer(*InitDecl); 5337 if (!Initializer) { 5338 QualType T = InitExpr->getType(); 5339 if (D->getType()->isReferenceType()) 5340 T = D->getType(); 5341 5342 if (getLangOpts().CPlusPlus) { 5343 if (InitDecl->hasFlexibleArrayInit(getContext())) 5344 ErrorUnsupported(D, "flexible array initializer"); 5345 Init = EmitNullConstant(T); 5346 5347 if (!IsDefinitionAvailableExternally) 5348 NeedsGlobalCtor = true; 5349 } else { 5350 ErrorUnsupported(D, "static initializer"); 5351 Init = llvm::UndefValue::get(getTypes().ConvertType(T)); 5352 } 5353 } else { 5354 Init = Initializer; 5355 // We don't need an initializer, so remove the entry for the delayed 5356 // initializer position (just in case this entry was delayed) if we 5357 // also don't need to register a destructor. 5358 if (getLangOpts().CPlusPlus && !NeedsGlobalDtor) 5359 DelayedCXXInitPosition.erase(D); 5360 5361 #ifndef NDEBUG 5362 CharUnits VarSize = getContext().getTypeSizeInChars(ASTTy) + 5363 InitDecl->getFlexibleArrayInitChars(getContext()); 5364 CharUnits CstSize = CharUnits::fromQuantity( 5365 getDataLayout().getTypeAllocSize(Init->getType())); 5366 assert(VarSize == CstSize && "Emitted constant has unexpected size"); 5367 #endif 5368 } 5369 } 5370 5371 llvm::Type* InitType = Init->getType(); 5372 llvm::Constant *Entry = 5373 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)); 5374 5375 // Strip off pointer casts if we got them. 5376 Entry = Entry->stripPointerCasts(); 5377 5378 // Entry is now either a Function or GlobalVariable. 5379 auto *GV = dyn_cast<llvm::GlobalVariable>(Entry); 5380 5381 // We have a definition after a declaration with the wrong type. 5382 // We must make a new GlobalVariable* and update everything that used OldGV 5383 // (a declaration or tentative definition) with the new GlobalVariable* 5384 // (which will be a definition). 5385 // 5386 // This happens if there is a prototype for a global (e.g. 5387 // "extern int x[];") and then a definition of a different type (e.g. 5388 // "int x[10];"). This also happens when an initializer has a different type 5389 // from the type of the global (this happens with unions). 5390 if (!GV || GV->getValueType() != InitType || 5391 GV->getType()->getAddressSpace() != 5392 getContext().getTargetAddressSpace(GetGlobalVarAddressSpace(D))) { 5393 5394 // Move the old entry aside so that we'll create a new one. 5395 Entry->setName(StringRef()); 5396 5397 // Make a new global with the correct type, this is now guaranteed to work. 5398 GV = cast<llvm::GlobalVariable>( 5399 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)) 5400 ->stripPointerCasts()); 5401 5402 // Replace all uses of the old global with the new global 5403 llvm::Constant *NewPtrForOldDecl = 5404 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, 5405 Entry->getType()); 5406 Entry->replaceAllUsesWith(NewPtrForOldDecl); 5407 5408 // Erase the old global, since it is no longer used. 5409 cast<llvm::GlobalValue>(Entry)->eraseFromParent(); 5410 } 5411 5412 MaybeHandleStaticInExternC(D, GV); 5413 5414 if (D->hasAttr<AnnotateAttr>()) 5415 AddGlobalAnnotations(D, GV); 5416 5417 // Set the llvm linkage type as appropriate. 5418 llvm::GlobalValue::LinkageTypes Linkage = getLLVMLinkageVarDefinition(D); 5419 5420 // CUDA B.2.1 "The __device__ qualifier declares a variable that resides on 5421 // the device. [...]" 5422 // CUDA B.2.2 "The __constant__ qualifier, optionally used together with 5423 // __device__, declares a variable that: [...] 5424 // Is accessible from all the threads within the grid and from the host 5425 // through the runtime library (cudaGetSymbolAddress() / cudaGetSymbolSize() 5426 // / cudaMemcpyToSymbol() / cudaMemcpyFromSymbol())." 5427 if (LangOpts.CUDA) { 5428 if (LangOpts.CUDAIsDevice) { 5429 if (Linkage != llvm::GlobalValue::InternalLinkage && 5430 (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>() || 5431 D->getType()->isCUDADeviceBuiltinSurfaceType() || 5432 D->getType()->isCUDADeviceBuiltinTextureType())) 5433 GV->setExternallyInitialized(true); 5434 } else { 5435 getCUDARuntime().internalizeDeviceSideVar(D, Linkage); 5436 } 5437 getCUDARuntime().handleVarRegistration(D, *GV); 5438 } 5439 5440 GV->setInitializer(Init); 5441 if (emitter) 5442 emitter->finalize(GV); 5443 5444 // If it is safe to mark the global 'constant', do so now. 5445 GV->setConstant(!NeedsGlobalCtor && !NeedsGlobalDtor && 5446 D->getType().isConstantStorage(getContext(), true, true)); 5447 5448 // If it is in a read-only section, mark it 'constant'. 5449 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) { 5450 const ASTContext::SectionInfo &SI = Context.SectionInfos[SA->getName()]; 5451 if ((SI.SectionFlags & ASTContext::PSF_Write) == 0) 5452 GV->setConstant(true); 5453 } 5454 5455 CharUnits AlignVal = getContext().getDeclAlign(D); 5456 // Check for alignment specifed in an 'omp allocate' directive. 5457 if (std::optional<CharUnits> AlignValFromAllocate = 5458 getOMPAllocateAlignment(D)) 5459 AlignVal = *AlignValFromAllocate; 5460 GV->setAlignment(AlignVal.getAsAlign()); 5461 5462 // On Darwin, unlike other Itanium C++ ABI platforms, the thread-wrapper 5463 // function is only defined alongside the variable, not also alongside 5464 // callers. Normally, all accesses to a thread_local go through the 5465 // thread-wrapper in order to ensure initialization has occurred, underlying 5466 // variable will never be used other than the thread-wrapper, so it can be 5467 // converted to internal linkage. 5468 // 5469 // However, if the variable has the 'constinit' attribute, it _can_ be 5470 // referenced directly, without calling the thread-wrapper, so the linkage 5471 // must not be changed. 5472 // 5473 // Additionally, if the variable isn't plain external linkage, e.g. if it's 5474 // weak or linkonce, the de-duplication semantics are important to preserve, 5475 // so we don't change the linkage. 5476 if (D->getTLSKind() == VarDecl::TLS_Dynamic && 5477 Linkage == llvm::GlobalValue::ExternalLinkage && 5478 Context.getTargetInfo().getTriple().isOSDarwin() && 5479 !D->hasAttr<ConstInitAttr>()) 5480 Linkage = llvm::GlobalValue::InternalLinkage; 5481 5482 GV->setLinkage(Linkage); 5483 if (D->hasAttr<DLLImportAttr>()) 5484 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass); 5485 else if (D->hasAttr<DLLExportAttr>()) 5486 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass); 5487 else 5488 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass); 5489 5490 if (Linkage == llvm::GlobalVariable::CommonLinkage) { 5491 // common vars aren't constant even if declared const. 5492 GV->setConstant(false); 5493 // Tentative definition of global variables may be initialized with 5494 // non-zero null pointers. In this case they should have weak linkage 5495 // since common linkage must have zero initializer and must not have 5496 // explicit section therefore cannot have non-zero initial value. 5497 if (!GV->getInitializer()->isNullValue()) 5498 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 5499 } 5500 5501 setNonAliasAttributes(D, GV); 5502 5503 if (D->getTLSKind() && !GV->isThreadLocal()) { 5504 if (D->getTLSKind() == VarDecl::TLS_Dynamic) 5505 CXXThreadLocals.push_back(D); 5506 setTLSMode(GV, *D); 5507 } 5508 5509 maybeSetTrivialComdat(*D, *GV); 5510 5511 // Emit the initializer function if necessary. 5512 if (NeedsGlobalCtor || NeedsGlobalDtor) 5513 EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor); 5514 5515 SanitizerMD->reportGlobal(GV, *D, NeedsGlobalCtor); 5516 5517 // Emit global variable debug information. 5518 if (CGDebugInfo *DI = getModuleDebugInfo()) 5519 if (getCodeGenOpts().hasReducedDebugInfo()) 5520 DI->EmitGlobalVariable(GV, D); 5521 } 5522 5523 void CodeGenModule::EmitExternalVarDeclaration(const VarDecl *D) { 5524 if (CGDebugInfo *DI = getModuleDebugInfo()) 5525 if (getCodeGenOpts().hasReducedDebugInfo()) { 5526 QualType ASTTy = D->getType(); 5527 llvm::Type *Ty = getTypes().ConvertTypeForMem(D->getType()); 5528 llvm::Constant *GV = 5529 GetOrCreateLLVMGlobal(D->getName(), Ty, ASTTy.getAddressSpace(), D); 5530 DI->EmitExternalVariable( 5531 cast<llvm::GlobalVariable>(GV->stripPointerCasts()), D); 5532 } 5533 } 5534 5535 static bool isVarDeclStrongDefinition(const ASTContext &Context, 5536 CodeGenModule &CGM, const VarDecl *D, 5537 bool NoCommon) { 5538 // Don't give variables common linkage if -fno-common was specified unless it 5539 // was overridden by a NoCommon attribute. 5540 if ((NoCommon || D->hasAttr<NoCommonAttr>()) && !D->hasAttr<CommonAttr>()) 5541 return true; 5542 5543 // C11 6.9.2/2: 5544 // A declaration of an identifier for an object that has file scope without 5545 // an initializer, and without a storage-class specifier or with the 5546 // storage-class specifier static, constitutes a tentative definition. 5547 if (D->getInit() || D->hasExternalStorage()) 5548 return true; 5549 5550 // A variable cannot be both common and exist in a section. 5551 if (D->hasAttr<SectionAttr>()) 5552 return true; 5553 5554 // A variable cannot be both common and exist in a section. 5555 // We don't try to determine which is the right section in the front-end. 5556 // If no specialized section name is applicable, it will resort to default. 5557 if (D->hasAttr<PragmaClangBSSSectionAttr>() || 5558 D->hasAttr<PragmaClangDataSectionAttr>() || 5559 D->hasAttr<PragmaClangRelroSectionAttr>() || 5560 D->hasAttr<PragmaClangRodataSectionAttr>()) 5561 return true; 5562 5563 // Thread local vars aren't considered common linkage. 5564 if (D->getTLSKind()) 5565 return true; 5566 5567 // Tentative definitions marked with WeakImportAttr are true definitions. 5568 if (D->hasAttr<WeakImportAttr>()) 5569 return true; 5570 5571 // A variable cannot be both common and exist in a comdat. 5572 if (shouldBeInCOMDAT(CGM, *D)) 5573 return true; 5574 5575 // Declarations with a required alignment do not have common linkage in MSVC 5576 // mode. 5577 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) { 5578 if (D->hasAttr<AlignedAttr>()) 5579 return true; 5580 QualType VarType = D->getType(); 5581 if (Context.isAlignmentRequired(VarType)) 5582 return true; 5583 5584 if (const auto *RT = VarType->getAs<RecordType>()) { 5585 const RecordDecl *RD = RT->getDecl(); 5586 for (const FieldDecl *FD : RD->fields()) { 5587 if (FD->isBitField()) 5588 continue; 5589 if (FD->hasAttr<AlignedAttr>()) 5590 return true; 5591 if (Context.isAlignmentRequired(FD->getType())) 5592 return true; 5593 } 5594 } 5595 } 5596 5597 // Microsoft's link.exe doesn't support alignments greater than 32 bytes for 5598 // common symbols, so symbols with greater alignment requirements cannot be 5599 // common. 5600 // Other COFF linkers (ld.bfd and LLD) support arbitrary power-of-two 5601 // alignments for common symbols via the aligncomm directive, so this 5602 // restriction only applies to MSVC environments. 5603 if (Context.getTargetInfo().getTriple().isKnownWindowsMSVCEnvironment() && 5604 Context.getTypeAlignIfKnown(D->getType()) > 5605 Context.toBits(CharUnits::fromQuantity(32))) 5606 return true; 5607 5608 return false; 5609 } 5610 5611 llvm::GlobalValue::LinkageTypes 5612 CodeGenModule::getLLVMLinkageForDeclarator(const DeclaratorDecl *D, 5613 GVALinkage Linkage) { 5614 if (Linkage == GVA_Internal) 5615 return llvm::Function::InternalLinkage; 5616 5617 if (D->hasAttr<WeakAttr>()) 5618 return llvm::GlobalVariable::WeakAnyLinkage; 5619 5620 if (const auto *FD = D->getAsFunction()) 5621 if (FD->isMultiVersion() && Linkage == GVA_AvailableExternally) 5622 return llvm::GlobalVariable::LinkOnceAnyLinkage; 5623 5624 // We are guaranteed to have a strong definition somewhere else, 5625 // so we can use available_externally linkage. 5626 if (Linkage == GVA_AvailableExternally) 5627 return llvm::GlobalValue::AvailableExternallyLinkage; 5628 5629 // Note that Apple's kernel linker doesn't support symbol 5630 // coalescing, so we need to avoid linkonce and weak linkages there. 5631 // Normally, this means we just map to internal, but for explicit 5632 // instantiations we'll map to external. 5633 5634 // In C++, the compiler has to emit a definition in every translation unit 5635 // that references the function. We should use linkonce_odr because 5636 // a) if all references in this translation unit are optimized away, we 5637 // don't need to codegen it. b) if the function persists, it needs to be 5638 // merged with other definitions. c) C++ has the ODR, so we know the 5639 // definition is dependable. 5640 if (Linkage == GVA_DiscardableODR) 5641 return !Context.getLangOpts().AppleKext ? llvm::Function::LinkOnceODRLinkage 5642 : llvm::Function::InternalLinkage; 5643 5644 // An explicit instantiation of a template has weak linkage, since 5645 // explicit instantiations can occur in multiple translation units 5646 // and must all be equivalent. However, we are not allowed to 5647 // throw away these explicit instantiations. 5648 // 5649 // CUDA/HIP: For -fno-gpu-rdc case, device code is limited to one TU, 5650 // so say that CUDA templates are either external (for kernels) or internal. 5651 // This lets llvm perform aggressive inter-procedural optimizations. For 5652 // -fgpu-rdc case, device function calls across multiple TU's are allowed, 5653 // therefore we need to follow the normal linkage paradigm. 5654 if (Linkage == GVA_StrongODR) { 5655 if (getLangOpts().AppleKext) 5656 return llvm::Function::ExternalLinkage; 5657 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice && 5658 !getLangOpts().GPURelocatableDeviceCode) 5659 return D->hasAttr<CUDAGlobalAttr>() ? llvm::Function::ExternalLinkage 5660 : llvm::Function::InternalLinkage; 5661 return llvm::Function::WeakODRLinkage; 5662 } 5663 5664 // C++ doesn't have tentative definitions and thus cannot have common 5665 // linkage. 5666 if (!getLangOpts().CPlusPlus && isa<VarDecl>(D) && 5667 !isVarDeclStrongDefinition(Context, *this, cast<VarDecl>(D), 5668 CodeGenOpts.NoCommon)) 5669 return llvm::GlobalVariable::CommonLinkage; 5670 5671 // selectany symbols are externally visible, so use weak instead of 5672 // linkonce. MSVC optimizes away references to const selectany globals, so 5673 // all definitions should be the same and ODR linkage should be used. 5674 // http://msdn.microsoft.com/en-us/library/5tkz6s71.aspx 5675 if (D->hasAttr<SelectAnyAttr>()) 5676 return llvm::GlobalVariable::WeakODRLinkage; 5677 5678 // Otherwise, we have strong external linkage. 5679 assert(Linkage == GVA_StrongExternal); 5680 return llvm::GlobalVariable::ExternalLinkage; 5681 } 5682 5683 llvm::GlobalValue::LinkageTypes 5684 CodeGenModule::getLLVMLinkageVarDefinition(const VarDecl *VD) { 5685 GVALinkage Linkage = getContext().GetGVALinkageForVariable(VD); 5686 return getLLVMLinkageForDeclarator(VD, Linkage); 5687 } 5688 5689 /// Replace the uses of a function that was declared with a non-proto type. 5690 /// We want to silently drop extra arguments from call sites 5691 static void replaceUsesOfNonProtoConstant(llvm::Constant *old, 5692 llvm::Function *newFn) { 5693 // Fast path. 5694 if (old->use_empty()) return; 5695 5696 llvm::Type *newRetTy = newFn->getReturnType(); 5697 SmallVector<llvm::Value*, 4> newArgs; 5698 5699 for (llvm::Value::use_iterator ui = old->use_begin(), ue = old->use_end(); 5700 ui != ue; ) { 5701 llvm::Value::use_iterator use = ui++; // Increment before the use is erased. 5702 llvm::User *user = use->getUser(); 5703 5704 // Recognize and replace uses of bitcasts. Most calls to 5705 // unprototyped functions will use bitcasts. 5706 if (auto *bitcast = dyn_cast<llvm::ConstantExpr>(user)) { 5707 if (bitcast->getOpcode() == llvm::Instruction::BitCast) 5708 replaceUsesOfNonProtoConstant(bitcast, newFn); 5709 continue; 5710 } 5711 5712 // Recognize calls to the function. 5713 llvm::CallBase *callSite = dyn_cast<llvm::CallBase>(user); 5714 if (!callSite) continue; 5715 if (!callSite->isCallee(&*use)) 5716 continue; 5717 5718 // If the return types don't match exactly, then we can't 5719 // transform this call unless it's dead. 5720 if (callSite->getType() != newRetTy && !callSite->use_empty()) 5721 continue; 5722 5723 // Get the call site's attribute list. 5724 SmallVector<llvm::AttributeSet, 8> newArgAttrs; 5725 llvm::AttributeList oldAttrs = callSite->getAttributes(); 5726 5727 // If the function was passed too few arguments, don't transform. 5728 unsigned newNumArgs = newFn->arg_size(); 5729 if (callSite->arg_size() < newNumArgs) 5730 continue; 5731 5732 // If extra arguments were passed, we silently drop them. 5733 // If any of the types mismatch, we don't transform. 5734 unsigned argNo = 0; 5735 bool dontTransform = false; 5736 for (llvm::Argument &A : newFn->args()) { 5737 if (callSite->getArgOperand(argNo)->getType() != A.getType()) { 5738 dontTransform = true; 5739 break; 5740 } 5741 5742 // Add any parameter attributes. 5743 newArgAttrs.push_back(oldAttrs.getParamAttrs(argNo)); 5744 argNo++; 5745 } 5746 if (dontTransform) 5747 continue; 5748 5749 // Okay, we can transform this. Create the new call instruction and copy 5750 // over the required information. 5751 newArgs.append(callSite->arg_begin(), callSite->arg_begin() + argNo); 5752 5753 // Copy over any operand bundles. 5754 SmallVector<llvm::OperandBundleDef, 1> newBundles; 5755 callSite->getOperandBundlesAsDefs(newBundles); 5756 5757 llvm::CallBase *newCall; 5758 if (isa<llvm::CallInst>(callSite)) { 5759 newCall = 5760 llvm::CallInst::Create(newFn, newArgs, newBundles, "", callSite); 5761 } else { 5762 auto *oldInvoke = cast<llvm::InvokeInst>(callSite); 5763 newCall = llvm::InvokeInst::Create(newFn, oldInvoke->getNormalDest(), 5764 oldInvoke->getUnwindDest(), newArgs, 5765 newBundles, "", callSite); 5766 } 5767 newArgs.clear(); // for the next iteration 5768 5769 if (!newCall->getType()->isVoidTy()) 5770 newCall->takeName(callSite); 5771 newCall->setAttributes( 5772 llvm::AttributeList::get(newFn->getContext(), oldAttrs.getFnAttrs(), 5773 oldAttrs.getRetAttrs(), newArgAttrs)); 5774 newCall->setCallingConv(callSite->getCallingConv()); 5775 5776 // Finally, remove the old call, replacing any uses with the new one. 5777 if (!callSite->use_empty()) 5778 callSite->replaceAllUsesWith(newCall); 5779 5780 // Copy debug location attached to CI. 5781 if (callSite->getDebugLoc()) 5782 newCall->setDebugLoc(callSite->getDebugLoc()); 5783 5784 callSite->eraseFromParent(); 5785 } 5786 } 5787 5788 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we 5789 /// implement a function with no prototype, e.g. "int foo() {}". If there are 5790 /// existing call uses of the old function in the module, this adjusts them to 5791 /// call the new function directly. 5792 /// 5793 /// This is not just a cleanup: the always_inline pass requires direct calls to 5794 /// functions to be able to inline them. If there is a bitcast in the way, it 5795 /// won't inline them. Instcombine normally deletes these calls, but it isn't 5796 /// run at -O0. 5797 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 5798 llvm::Function *NewFn) { 5799 // If we're redefining a global as a function, don't transform it. 5800 if (!isa<llvm::Function>(Old)) return; 5801 5802 replaceUsesOfNonProtoConstant(Old, NewFn); 5803 } 5804 5805 void CodeGenModule::HandleCXXStaticMemberVarInstantiation(VarDecl *VD) { 5806 auto DK = VD->isThisDeclarationADefinition(); 5807 if (DK == VarDecl::Definition && VD->hasAttr<DLLImportAttr>()) 5808 return; 5809 5810 TemplateSpecializationKind TSK = VD->getTemplateSpecializationKind(); 5811 // If we have a definition, this might be a deferred decl. If the 5812 // instantiation is explicit, make sure we emit it at the end. 5813 if (VD->getDefinition() && TSK == TSK_ExplicitInstantiationDefinition) 5814 GetAddrOfGlobalVar(VD); 5815 5816 EmitTopLevelDecl(VD); 5817 } 5818 5819 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD, 5820 llvm::GlobalValue *GV) { 5821 const auto *D = cast<FunctionDecl>(GD.getDecl()); 5822 5823 // Compute the function info and LLVM type. 5824 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 5825 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 5826 5827 // Get or create the prototype for the function. 5828 if (!GV || (GV->getValueType() != Ty)) 5829 GV = cast<llvm::GlobalValue>(GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, 5830 /*DontDefer=*/true, 5831 ForDefinition)); 5832 5833 // Already emitted. 5834 if (!GV->isDeclaration()) 5835 return; 5836 5837 // We need to set linkage and visibility on the function before 5838 // generating code for it because various parts of IR generation 5839 // want to propagate this information down (e.g. to local static 5840 // declarations). 5841 auto *Fn = cast<llvm::Function>(GV); 5842 setFunctionLinkage(GD, Fn); 5843 5844 // FIXME: this is redundant with part of setFunctionDefinitionAttributes 5845 setGVProperties(Fn, GD); 5846 5847 MaybeHandleStaticInExternC(D, Fn); 5848 5849 maybeSetTrivialComdat(*D, *Fn); 5850 5851 CodeGenFunction(*this).GenerateCode(GD, Fn, FI); 5852 5853 setNonAliasAttributes(GD, Fn); 5854 SetLLVMFunctionAttributesForDefinition(D, Fn); 5855 5856 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>()) 5857 AddGlobalCtor(Fn, CA->getPriority()); 5858 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>()) 5859 AddGlobalDtor(Fn, DA->getPriority(), true); 5860 if (getLangOpts().OpenMP && D->hasAttr<OMPDeclareTargetDeclAttr>()) 5861 getOpenMPRuntime().emitDeclareTargetFunction(D, GV); 5862 } 5863 5864 void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) { 5865 const auto *D = cast<ValueDecl>(GD.getDecl()); 5866 const AliasAttr *AA = D->getAttr<AliasAttr>(); 5867 assert(AA && "Not an alias?"); 5868 5869 StringRef MangledName = getMangledName(GD); 5870 5871 if (AA->getAliasee() == MangledName) { 5872 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0; 5873 return; 5874 } 5875 5876 // If there is a definition in the module, then it wins over the alias. 5877 // This is dubious, but allow it to be safe. Just ignore the alias. 5878 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 5879 if (Entry && !Entry->isDeclaration()) 5880 return; 5881 5882 Aliases.push_back(GD); 5883 5884 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 5885 5886 // Create a reference to the named value. This ensures that it is emitted 5887 // if a deferred decl. 5888 llvm::Constant *Aliasee; 5889 llvm::GlobalValue::LinkageTypes LT; 5890 if (isa<llvm::FunctionType>(DeclTy)) { 5891 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GD, 5892 /*ForVTable=*/false); 5893 LT = getFunctionLinkage(GD); 5894 } else { 5895 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, LangAS::Default, 5896 /*D=*/nullptr); 5897 if (const auto *VD = dyn_cast<VarDecl>(GD.getDecl())) 5898 LT = getLLVMLinkageVarDefinition(VD); 5899 else 5900 LT = getFunctionLinkage(GD); 5901 } 5902 5903 // Create the new alias itself, but don't set a name yet. 5904 unsigned AS = Aliasee->getType()->getPointerAddressSpace(); 5905 auto *GA = 5906 llvm::GlobalAlias::create(DeclTy, AS, LT, "", Aliasee, &getModule()); 5907 5908 if (Entry) { 5909 if (GA->getAliasee() == Entry) { 5910 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0; 5911 return; 5912 } 5913 5914 assert(Entry->isDeclaration()); 5915 5916 // If there is a declaration in the module, then we had an extern followed 5917 // by the alias, as in: 5918 // extern int test6(); 5919 // ... 5920 // int test6() __attribute__((alias("test7"))); 5921 // 5922 // Remove it and replace uses of it with the alias. 5923 GA->takeName(Entry); 5924 5925 Entry->replaceAllUsesWith(GA); 5926 Entry->eraseFromParent(); 5927 } else { 5928 GA->setName(MangledName); 5929 } 5930 5931 // Set attributes which are particular to an alias; this is a 5932 // specialization of the attributes which may be set on a global 5933 // variable/function. 5934 if (D->hasAttr<WeakAttr>() || D->hasAttr<WeakRefAttr>() || 5935 D->isWeakImported()) { 5936 GA->setLinkage(llvm::Function::WeakAnyLinkage); 5937 } 5938 5939 if (const auto *VD = dyn_cast<VarDecl>(D)) 5940 if (VD->getTLSKind()) 5941 setTLSMode(GA, *VD); 5942 5943 SetCommonAttributes(GD, GA); 5944 5945 // Emit global alias debug information. 5946 if (isa<VarDecl>(D)) 5947 if (CGDebugInfo *DI = getModuleDebugInfo()) 5948 DI->EmitGlobalAlias(cast<llvm::GlobalValue>(GA->getAliasee()->stripPointerCasts()), GD); 5949 } 5950 5951 void CodeGenModule::emitIFuncDefinition(GlobalDecl GD) { 5952 const auto *D = cast<ValueDecl>(GD.getDecl()); 5953 const IFuncAttr *IFA = D->getAttr<IFuncAttr>(); 5954 assert(IFA && "Not an ifunc?"); 5955 5956 StringRef MangledName = getMangledName(GD); 5957 5958 if (IFA->getResolver() == MangledName) { 5959 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1; 5960 return; 5961 } 5962 5963 // Report an error if some definition overrides ifunc. 5964 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 5965 if (Entry && !Entry->isDeclaration()) { 5966 GlobalDecl OtherGD; 5967 if (lookupRepresentativeDecl(MangledName, OtherGD) && 5968 DiagnosedConflictingDefinitions.insert(GD).second) { 5969 Diags.Report(D->getLocation(), diag::err_duplicate_mangled_name) 5970 << MangledName; 5971 Diags.Report(OtherGD.getDecl()->getLocation(), 5972 diag::note_previous_definition); 5973 } 5974 return; 5975 } 5976 5977 Aliases.push_back(GD); 5978 5979 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 5980 llvm::Type *ResolverTy = llvm::GlobalIFunc::getResolverFunctionType(DeclTy); 5981 llvm::Constant *Resolver = 5982 GetOrCreateLLVMFunction(IFA->getResolver(), ResolverTy, {}, 5983 /*ForVTable=*/false); 5984 llvm::GlobalIFunc *GIF = 5985 llvm::GlobalIFunc::create(DeclTy, 0, llvm::Function::ExternalLinkage, 5986 "", Resolver, &getModule()); 5987 if (Entry) { 5988 if (GIF->getResolver() == Entry) { 5989 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1; 5990 return; 5991 } 5992 assert(Entry->isDeclaration()); 5993 5994 // If there is a declaration in the module, then we had an extern followed 5995 // by the ifunc, as in: 5996 // extern int test(); 5997 // ... 5998 // int test() __attribute__((ifunc("resolver"))); 5999 // 6000 // Remove it and replace uses of it with the ifunc. 6001 GIF->takeName(Entry); 6002 6003 Entry->replaceAllUsesWith(GIF); 6004 Entry->eraseFromParent(); 6005 } else 6006 GIF->setName(MangledName); 6007 if (auto *F = dyn_cast<llvm::Function>(Resolver)) { 6008 F->addFnAttr(llvm::Attribute::DisableSanitizerInstrumentation); 6009 } 6010 SetCommonAttributes(GD, GIF); 6011 } 6012 6013 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID, 6014 ArrayRef<llvm::Type*> Tys) { 6015 return llvm::Intrinsic::getDeclaration(&getModule(), (llvm::Intrinsic::ID)IID, 6016 Tys); 6017 } 6018 6019 static llvm::StringMapEntry<llvm::GlobalVariable *> & 6020 GetConstantCFStringEntry(llvm::StringMap<llvm::GlobalVariable *> &Map, 6021 const StringLiteral *Literal, bool TargetIsLSB, 6022 bool &IsUTF16, unsigned &StringLength) { 6023 StringRef String = Literal->getString(); 6024 unsigned NumBytes = String.size(); 6025 6026 // Check for simple case. 6027 if (!Literal->containsNonAsciiOrNull()) { 6028 StringLength = NumBytes; 6029 return *Map.insert(std::make_pair(String, nullptr)).first; 6030 } 6031 6032 // Otherwise, convert the UTF8 literals into a string of shorts. 6033 IsUTF16 = true; 6034 6035 SmallVector<llvm::UTF16, 128> ToBuf(NumBytes + 1); // +1 for ending nulls. 6036 const llvm::UTF8 *FromPtr = (const llvm::UTF8 *)String.data(); 6037 llvm::UTF16 *ToPtr = &ToBuf[0]; 6038 6039 (void)llvm::ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, &ToPtr, 6040 ToPtr + NumBytes, llvm::strictConversion); 6041 6042 // ConvertUTF8toUTF16 returns the length in ToPtr. 6043 StringLength = ToPtr - &ToBuf[0]; 6044 6045 // Add an explicit null. 6046 *ToPtr = 0; 6047 return *Map.insert(std::make_pair( 6048 StringRef(reinterpret_cast<const char *>(ToBuf.data()), 6049 (StringLength + 1) * 2), 6050 nullptr)).first; 6051 } 6052 6053 ConstantAddress 6054 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { 6055 unsigned StringLength = 0; 6056 bool isUTF16 = false; 6057 llvm::StringMapEntry<llvm::GlobalVariable *> &Entry = 6058 GetConstantCFStringEntry(CFConstantStringMap, Literal, 6059 getDataLayout().isLittleEndian(), isUTF16, 6060 StringLength); 6061 6062 if (auto *C = Entry.second) 6063 return ConstantAddress( 6064 C, C->getValueType(), CharUnits::fromQuantity(C->getAlignment())); 6065 6066 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty); 6067 llvm::Constant *Zeros[] = { Zero, Zero }; 6068 6069 const ASTContext &Context = getContext(); 6070 const llvm::Triple &Triple = getTriple(); 6071 6072 const auto CFRuntime = getLangOpts().CFRuntime; 6073 const bool IsSwiftABI = 6074 static_cast<unsigned>(CFRuntime) >= 6075 static_cast<unsigned>(LangOptions::CoreFoundationABI::Swift); 6076 const bool IsSwift4_1 = CFRuntime == LangOptions::CoreFoundationABI::Swift4_1; 6077 6078 // If we don't already have it, get __CFConstantStringClassReference. 6079 if (!CFConstantStringClassRef) { 6080 const char *CFConstantStringClassName = "__CFConstantStringClassReference"; 6081 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); 6082 Ty = llvm::ArrayType::get(Ty, 0); 6083 6084 switch (CFRuntime) { 6085 default: break; 6086 case LangOptions::CoreFoundationABI::Swift: [[fallthrough]]; 6087 case LangOptions::CoreFoundationABI::Swift5_0: 6088 CFConstantStringClassName = 6089 Triple.isOSDarwin() ? "$s15SwiftFoundation19_NSCFConstantStringCN" 6090 : "$s10Foundation19_NSCFConstantStringCN"; 6091 Ty = IntPtrTy; 6092 break; 6093 case LangOptions::CoreFoundationABI::Swift4_2: 6094 CFConstantStringClassName = 6095 Triple.isOSDarwin() ? "$S15SwiftFoundation19_NSCFConstantStringCN" 6096 : "$S10Foundation19_NSCFConstantStringCN"; 6097 Ty = IntPtrTy; 6098 break; 6099 case LangOptions::CoreFoundationABI::Swift4_1: 6100 CFConstantStringClassName = 6101 Triple.isOSDarwin() ? "__T015SwiftFoundation19_NSCFConstantStringCN" 6102 : "__T010Foundation19_NSCFConstantStringCN"; 6103 Ty = IntPtrTy; 6104 break; 6105 } 6106 6107 llvm::Constant *C = CreateRuntimeVariable(Ty, CFConstantStringClassName); 6108 6109 if (Triple.isOSBinFormatELF() || Triple.isOSBinFormatCOFF()) { 6110 llvm::GlobalValue *GV = nullptr; 6111 6112 if ((GV = dyn_cast<llvm::GlobalValue>(C))) { 6113 IdentifierInfo &II = Context.Idents.get(GV->getName()); 6114 TranslationUnitDecl *TUDecl = Context.getTranslationUnitDecl(); 6115 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); 6116 6117 const VarDecl *VD = nullptr; 6118 for (const auto *Result : DC->lookup(&II)) 6119 if ((VD = dyn_cast<VarDecl>(Result))) 6120 break; 6121 6122 if (Triple.isOSBinFormatELF()) { 6123 if (!VD) 6124 GV->setLinkage(llvm::GlobalValue::ExternalLinkage); 6125 } else { 6126 GV->setLinkage(llvm::GlobalValue::ExternalLinkage); 6127 if (!VD || !VD->hasAttr<DLLExportAttr>()) 6128 GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass); 6129 else 6130 GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass); 6131 } 6132 6133 setDSOLocal(GV); 6134 } 6135 } 6136 6137 // Decay array -> ptr 6138 CFConstantStringClassRef = 6139 IsSwiftABI ? llvm::ConstantExpr::getPtrToInt(C, Ty) 6140 : llvm::ConstantExpr::getGetElementPtr(Ty, C, Zeros); 6141 } 6142 6143 QualType CFTy = Context.getCFConstantStringType(); 6144 6145 auto *STy = cast<llvm::StructType>(getTypes().ConvertType(CFTy)); 6146 6147 ConstantInitBuilder Builder(*this); 6148 auto Fields = Builder.beginStruct(STy); 6149 6150 // Class pointer. 6151 Fields.add(cast<llvm::Constant>(CFConstantStringClassRef)); 6152 6153 // Flags. 6154 if (IsSwiftABI) { 6155 Fields.addInt(IntPtrTy, IsSwift4_1 ? 0x05 : 0x01); 6156 Fields.addInt(Int64Ty, isUTF16 ? 0x07d0 : 0x07c8); 6157 } else { 6158 Fields.addInt(IntTy, isUTF16 ? 0x07d0 : 0x07C8); 6159 } 6160 6161 // String pointer. 6162 llvm::Constant *C = nullptr; 6163 if (isUTF16) { 6164 auto Arr = llvm::ArrayRef( 6165 reinterpret_cast<uint16_t *>(const_cast<char *>(Entry.first().data())), 6166 Entry.first().size() / 2); 6167 C = llvm::ConstantDataArray::get(VMContext, Arr); 6168 } else { 6169 C = llvm::ConstantDataArray::getString(VMContext, Entry.first()); 6170 } 6171 6172 // Note: -fwritable-strings doesn't make the backing store strings of 6173 // CFStrings writable. 6174 auto *GV = 6175 new llvm::GlobalVariable(getModule(), C->getType(), /*isConstant=*/true, 6176 llvm::GlobalValue::PrivateLinkage, C, ".str"); 6177 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 6178 // Don't enforce the target's minimum global alignment, since the only use 6179 // of the string is via this class initializer. 6180 CharUnits Align = isUTF16 ? Context.getTypeAlignInChars(Context.ShortTy) 6181 : Context.getTypeAlignInChars(Context.CharTy); 6182 GV->setAlignment(Align.getAsAlign()); 6183 6184 // FIXME: We set the section explicitly to avoid a bug in ld64 224.1. 6185 // Without it LLVM can merge the string with a non unnamed_addr one during 6186 // LTO. Doing that changes the section it ends in, which surprises ld64. 6187 if (Triple.isOSBinFormatMachO()) 6188 GV->setSection(isUTF16 ? "__TEXT,__ustring" 6189 : "__TEXT,__cstring,cstring_literals"); 6190 // Make sure the literal ends up in .rodata to allow for safe ICF and for 6191 // the static linker to adjust permissions to read-only later on. 6192 else if (Triple.isOSBinFormatELF()) 6193 GV->setSection(".rodata"); 6194 6195 // String. 6196 llvm::Constant *Str = 6197 llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV, Zeros); 6198 6199 Fields.add(Str); 6200 6201 // String length. 6202 llvm::IntegerType *LengthTy = 6203 llvm::IntegerType::get(getModule().getContext(), 6204 Context.getTargetInfo().getLongWidth()); 6205 if (IsSwiftABI) { 6206 if (CFRuntime == LangOptions::CoreFoundationABI::Swift4_1 || 6207 CFRuntime == LangOptions::CoreFoundationABI::Swift4_2) 6208 LengthTy = Int32Ty; 6209 else 6210 LengthTy = IntPtrTy; 6211 } 6212 Fields.addInt(LengthTy, StringLength); 6213 6214 // Swift ABI requires 8-byte alignment to ensure that the _Atomic(uint64_t) is 6215 // properly aligned on 32-bit platforms. 6216 CharUnits Alignment = 6217 IsSwiftABI ? Context.toCharUnitsFromBits(64) : getPointerAlign(); 6218 6219 // The struct. 6220 GV = Fields.finishAndCreateGlobal("_unnamed_cfstring_", Alignment, 6221 /*isConstant=*/false, 6222 llvm::GlobalVariable::PrivateLinkage); 6223 GV->addAttribute("objc_arc_inert"); 6224 switch (Triple.getObjectFormat()) { 6225 case llvm::Triple::UnknownObjectFormat: 6226 llvm_unreachable("unknown file format"); 6227 case llvm::Triple::DXContainer: 6228 case llvm::Triple::GOFF: 6229 case llvm::Triple::SPIRV: 6230 case llvm::Triple::XCOFF: 6231 llvm_unreachable("unimplemented"); 6232 case llvm::Triple::COFF: 6233 case llvm::Triple::ELF: 6234 case llvm::Triple::Wasm: 6235 GV->setSection("cfstring"); 6236 break; 6237 case llvm::Triple::MachO: 6238 GV->setSection("__DATA,__cfstring"); 6239 break; 6240 } 6241 Entry.second = GV; 6242 6243 return ConstantAddress(GV, GV->getValueType(), Alignment); 6244 } 6245 6246 bool CodeGenModule::getExpressionLocationsEnabled() const { 6247 return !CodeGenOpts.EmitCodeView || CodeGenOpts.DebugColumnInfo; 6248 } 6249 6250 QualType CodeGenModule::getObjCFastEnumerationStateType() { 6251 if (ObjCFastEnumerationStateType.isNull()) { 6252 RecordDecl *D = Context.buildImplicitRecord("__objcFastEnumerationState"); 6253 D->startDefinition(); 6254 6255 QualType FieldTypes[] = { 6256 Context.UnsignedLongTy, Context.getPointerType(Context.getObjCIdType()), 6257 Context.getPointerType(Context.UnsignedLongTy), 6258 Context.getConstantArrayType(Context.UnsignedLongTy, llvm::APInt(32, 5), 6259 nullptr, ArraySizeModifier::Normal, 0)}; 6260 6261 for (size_t i = 0; i < 4; ++i) { 6262 FieldDecl *Field = FieldDecl::Create(Context, 6263 D, 6264 SourceLocation(), 6265 SourceLocation(), nullptr, 6266 FieldTypes[i], /*TInfo=*/nullptr, 6267 /*BitWidth=*/nullptr, 6268 /*Mutable=*/false, 6269 ICIS_NoInit); 6270 Field->setAccess(AS_public); 6271 D->addDecl(Field); 6272 } 6273 6274 D->completeDefinition(); 6275 ObjCFastEnumerationStateType = Context.getTagDeclType(D); 6276 } 6277 6278 return ObjCFastEnumerationStateType; 6279 } 6280 6281 llvm::Constant * 6282 CodeGenModule::GetConstantArrayFromStringLiteral(const StringLiteral *E) { 6283 assert(!E->getType()->isPointerType() && "Strings are always arrays"); 6284 6285 // Don't emit it as the address of the string, emit the string data itself 6286 // as an inline array. 6287 if (E->getCharByteWidth() == 1) { 6288 SmallString<64> Str(E->getString()); 6289 6290 // Resize the string to the right size, which is indicated by its type. 6291 const ConstantArrayType *CAT = Context.getAsConstantArrayType(E->getType()); 6292 assert(CAT && "String literal not of constant array type!"); 6293 Str.resize(CAT->getZExtSize()); 6294 return llvm::ConstantDataArray::getString(VMContext, Str, false); 6295 } 6296 6297 auto *AType = cast<llvm::ArrayType>(getTypes().ConvertType(E->getType())); 6298 llvm::Type *ElemTy = AType->getElementType(); 6299 unsigned NumElements = AType->getNumElements(); 6300 6301 // Wide strings have either 2-byte or 4-byte elements. 6302 if (ElemTy->getPrimitiveSizeInBits() == 16) { 6303 SmallVector<uint16_t, 32> Elements; 6304 Elements.reserve(NumElements); 6305 6306 for(unsigned i = 0, e = E->getLength(); i != e; ++i) 6307 Elements.push_back(E->getCodeUnit(i)); 6308 Elements.resize(NumElements); 6309 return llvm::ConstantDataArray::get(VMContext, Elements); 6310 } 6311 6312 assert(ElemTy->getPrimitiveSizeInBits() == 32); 6313 SmallVector<uint32_t, 32> Elements; 6314 Elements.reserve(NumElements); 6315 6316 for(unsigned i = 0, e = E->getLength(); i != e; ++i) 6317 Elements.push_back(E->getCodeUnit(i)); 6318 Elements.resize(NumElements); 6319 return llvm::ConstantDataArray::get(VMContext, Elements); 6320 } 6321 6322 static llvm::GlobalVariable * 6323 GenerateStringLiteral(llvm::Constant *C, llvm::GlobalValue::LinkageTypes LT, 6324 CodeGenModule &CGM, StringRef GlobalName, 6325 CharUnits Alignment) { 6326 unsigned AddrSpace = CGM.getContext().getTargetAddressSpace( 6327 CGM.GetGlobalConstantAddressSpace()); 6328 6329 llvm::Module &M = CGM.getModule(); 6330 // Create a global variable for this string 6331 auto *GV = new llvm::GlobalVariable( 6332 M, C->getType(), !CGM.getLangOpts().WritableStrings, LT, C, GlobalName, 6333 nullptr, llvm::GlobalVariable::NotThreadLocal, AddrSpace); 6334 GV->setAlignment(Alignment.getAsAlign()); 6335 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 6336 if (GV->isWeakForLinker()) { 6337 assert(CGM.supportsCOMDAT() && "Only COFF uses weak string literals"); 6338 GV->setComdat(M.getOrInsertComdat(GV->getName())); 6339 } 6340 CGM.setDSOLocal(GV); 6341 6342 return GV; 6343 } 6344 6345 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a 6346 /// constant array for the given string literal. 6347 ConstantAddress 6348 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S, 6349 StringRef Name) { 6350 CharUnits Alignment = 6351 getContext().getAlignOfGlobalVarInChars(S->getType(), /*VD=*/nullptr); 6352 6353 llvm::Constant *C = GetConstantArrayFromStringLiteral(S); 6354 llvm::GlobalVariable **Entry = nullptr; 6355 if (!LangOpts.WritableStrings) { 6356 Entry = &ConstantStringMap[C]; 6357 if (auto GV = *Entry) { 6358 if (uint64_t(Alignment.getQuantity()) > GV->getAlignment()) 6359 GV->setAlignment(Alignment.getAsAlign()); 6360 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6361 GV->getValueType(), Alignment); 6362 } 6363 } 6364 6365 SmallString<256> MangledNameBuffer; 6366 StringRef GlobalVariableName; 6367 llvm::GlobalValue::LinkageTypes LT; 6368 6369 // Mangle the string literal if that's how the ABI merges duplicate strings. 6370 // Don't do it if they are writable, since we don't want writes in one TU to 6371 // affect strings in another. 6372 if (getCXXABI().getMangleContext().shouldMangleStringLiteral(S) && 6373 !LangOpts.WritableStrings) { 6374 llvm::raw_svector_ostream Out(MangledNameBuffer); 6375 getCXXABI().getMangleContext().mangleStringLiteral(S, Out); 6376 LT = llvm::GlobalValue::LinkOnceODRLinkage; 6377 GlobalVariableName = MangledNameBuffer; 6378 } else { 6379 LT = llvm::GlobalValue::PrivateLinkage; 6380 GlobalVariableName = Name; 6381 } 6382 6383 auto GV = GenerateStringLiteral(C, LT, *this, GlobalVariableName, Alignment); 6384 6385 CGDebugInfo *DI = getModuleDebugInfo(); 6386 if (DI && getCodeGenOpts().hasReducedDebugInfo()) 6387 DI->AddStringLiteralDebugInfo(GV, S); 6388 6389 if (Entry) 6390 *Entry = GV; 6391 6392 SanitizerMD->reportGlobal(GV, S->getStrTokenLoc(0), "<string literal>"); 6393 6394 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6395 GV->getValueType(), Alignment); 6396 } 6397 6398 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant 6399 /// array for the given ObjCEncodeExpr node. 6400 ConstantAddress 6401 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) { 6402 std::string Str; 6403 getContext().getObjCEncodingForType(E->getEncodedType(), Str); 6404 6405 return GetAddrOfConstantCString(Str); 6406 } 6407 6408 /// GetAddrOfConstantCString - Returns a pointer to a character array containing 6409 /// the literal and a terminating '\0' character. 6410 /// The result has pointer to array type. 6411 ConstantAddress CodeGenModule::GetAddrOfConstantCString( 6412 const std::string &Str, const char *GlobalName) { 6413 StringRef StrWithNull(Str.c_str(), Str.size() + 1); 6414 CharUnits Alignment = getContext().getAlignOfGlobalVarInChars( 6415 getContext().CharTy, /*VD=*/nullptr); 6416 6417 llvm::Constant *C = 6418 llvm::ConstantDataArray::getString(getLLVMContext(), StrWithNull, false); 6419 6420 // Don't share any string literals if strings aren't constant. 6421 llvm::GlobalVariable **Entry = nullptr; 6422 if (!LangOpts.WritableStrings) { 6423 Entry = &ConstantStringMap[C]; 6424 if (auto GV = *Entry) { 6425 if (uint64_t(Alignment.getQuantity()) > GV->getAlignment()) 6426 GV->setAlignment(Alignment.getAsAlign()); 6427 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6428 GV->getValueType(), Alignment); 6429 } 6430 } 6431 6432 // Get the default prefix if a name wasn't specified. 6433 if (!GlobalName) 6434 GlobalName = ".str"; 6435 // Create a global variable for this. 6436 auto GV = GenerateStringLiteral(C, llvm::GlobalValue::PrivateLinkage, *this, 6437 GlobalName, Alignment); 6438 if (Entry) 6439 *Entry = GV; 6440 6441 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6442 GV->getValueType(), Alignment); 6443 } 6444 6445 ConstantAddress CodeGenModule::GetAddrOfGlobalTemporary( 6446 const MaterializeTemporaryExpr *E, const Expr *Init) { 6447 assert((E->getStorageDuration() == SD_Static || 6448 E->getStorageDuration() == SD_Thread) && "not a global temporary"); 6449 const auto *VD = cast<VarDecl>(E->getExtendingDecl()); 6450 6451 // If we're not materializing a subobject of the temporary, keep the 6452 // cv-qualifiers from the type of the MaterializeTemporaryExpr. 6453 QualType MaterializedType = Init->getType(); 6454 if (Init == E->getSubExpr()) 6455 MaterializedType = E->getType(); 6456 6457 CharUnits Align = getContext().getTypeAlignInChars(MaterializedType); 6458 6459 auto InsertResult = MaterializedGlobalTemporaryMap.insert({E, nullptr}); 6460 if (!InsertResult.second) { 6461 // We've seen this before: either we already created it or we're in the 6462 // process of doing so. 6463 if (!InsertResult.first->second) { 6464 // We recursively re-entered this function, probably during emission of 6465 // the initializer. Create a placeholder. We'll clean this up in the 6466 // outer call, at the end of this function. 6467 llvm::Type *Type = getTypes().ConvertTypeForMem(MaterializedType); 6468 InsertResult.first->second = new llvm::GlobalVariable( 6469 getModule(), Type, false, llvm::GlobalVariable::InternalLinkage, 6470 nullptr); 6471 } 6472 return ConstantAddress(InsertResult.first->second, 6473 llvm::cast<llvm::GlobalVariable>( 6474 InsertResult.first->second->stripPointerCasts()) 6475 ->getValueType(), 6476 Align); 6477 } 6478 6479 // FIXME: If an externally-visible declaration extends multiple temporaries, 6480 // we need to give each temporary the same name in every translation unit (and 6481 // we also need to make the temporaries externally-visible). 6482 SmallString<256> Name; 6483 llvm::raw_svector_ostream Out(Name); 6484 getCXXABI().getMangleContext().mangleReferenceTemporary( 6485 VD, E->getManglingNumber(), Out); 6486 6487 APValue *Value = nullptr; 6488 if (E->getStorageDuration() == SD_Static && VD->evaluateValue()) { 6489 // If the initializer of the extending declaration is a constant 6490 // initializer, we should have a cached constant initializer for this 6491 // temporary. Note that this might have a different value from the value 6492 // computed by evaluating the initializer if the surrounding constant 6493 // expression modifies the temporary. 6494 Value = E->getOrCreateValue(false); 6495 } 6496 6497 // Try evaluating it now, it might have a constant initializer. 6498 Expr::EvalResult EvalResult; 6499 if (!Value && Init->EvaluateAsRValue(EvalResult, getContext()) && 6500 !EvalResult.hasSideEffects()) 6501 Value = &EvalResult.Val; 6502 6503 LangAS AddrSpace = GetGlobalVarAddressSpace(VD); 6504 6505 std::optional<ConstantEmitter> emitter; 6506 llvm::Constant *InitialValue = nullptr; 6507 bool Constant = false; 6508 llvm::Type *Type; 6509 if (Value) { 6510 // The temporary has a constant initializer, use it. 6511 emitter.emplace(*this); 6512 InitialValue = emitter->emitForInitializer(*Value, AddrSpace, 6513 MaterializedType); 6514 Constant = 6515 MaterializedType.isConstantStorage(getContext(), /*ExcludeCtor*/ Value, 6516 /*ExcludeDtor*/ false); 6517 Type = InitialValue->getType(); 6518 } else { 6519 // No initializer, the initialization will be provided when we 6520 // initialize the declaration which performed lifetime extension. 6521 Type = getTypes().ConvertTypeForMem(MaterializedType); 6522 } 6523 6524 // Create a global variable for this lifetime-extended temporary. 6525 llvm::GlobalValue::LinkageTypes Linkage = getLLVMLinkageVarDefinition(VD); 6526 if (Linkage == llvm::GlobalVariable::ExternalLinkage) { 6527 const VarDecl *InitVD; 6528 if (VD->isStaticDataMember() && VD->getAnyInitializer(InitVD) && 6529 isa<CXXRecordDecl>(InitVD->getLexicalDeclContext())) { 6530 // Temporaries defined inside a class get linkonce_odr linkage because the 6531 // class can be defined in multiple translation units. 6532 Linkage = llvm::GlobalVariable::LinkOnceODRLinkage; 6533 } else { 6534 // There is no need for this temporary to have external linkage if the 6535 // VarDecl has external linkage. 6536 Linkage = llvm::GlobalVariable::InternalLinkage; 6537 } 6538 } 6539 auto TargetAS = getContext().getTargetAddressSpace(AddrSpace); 6540 auto *GV = new llvm::GlobalVariable( 6541 getModule(), Type, Constant, Linkage, InitialValue, Name.c_str(), 6542 /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal, TargetAS); 6543 if (emitter) emitter->finalize(GV); 6544 // Don't assign dllimport or dllexport to local linkage globals. 6545 if (!llvm::GlobalValue::isLocalLinkage(Linkage)) { 6546 setGVProperties(GV, VD); 6547 if (GV->getDLLStorageClass() == llvm::GlobalVariable::DLLExportStorageClass) 6548 // The reference temporary should never be dllexport. 6549 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass); 6550 } 6551 GV->setAlignment(Align.getAsAlign()); 6552 if (supportsCOMDAT() && GV->isWeakForLinker()) 6553 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 6554 if (VD->getTLSKind()) 6555 setTLSMode(GV, *VD); 6556 llvm::Constant *CV = GV; 6557 if (AddrSpace != LangAS::Default) 6558 CV = getTargetCodeGenInfo().performAddrSpaceCast( 6559 *this, GV, AddrSpace, LangAS::Default, 6560 llvm::PointerType::get( 6561 getLLVMContext(), 6562 getContext().getTargetAddressSpace(LangAS::Default))); 6563 6564 // Update the map with the new temporary. If we created a placeholder above, 6565 // replace it with the new global now. 6566 llvm::Constant *&Entry = MaterializedGlobalTemporaryMap[E]; 6567 if (Entry) { 6568 Entry->replaceAllUsesWith(CV); 6569 llvm::cast<llvm::GlobalVariable>(Entry)->eraseFromParent(); 6570 } 6571 Entry = CV; 6572 6573 return ConstantAddress(CV, Type, Align); 6574 } 6575 6576 /// EmitObjCPropertyImplementations - Emit information for synthesized 6577 /// properties for an implementation. 6578 void CodeGenModule::EmitObjCPropertyImplementations(const 6579 ObjCImplementationDecl *D) { 6580 for (const auto *PID : D->property_impls()) { 6581 // Dynamic is just for type-checking. 6582 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) { 6583 ObjCPropertyDecl *PD = PID->getPropertyDecl(); 6584 6585 // Determine which methods need to be implemented, some may have 6586 // been overridden. Note that ::isPropertyAccessor is not the method 6587 // we want, that just indicates if the decl came from a 6588 // property. What we want to know is if the method is defined in 6589 // this implementation. 6590 auto *Getter = PID->getGetterMethodDecl(); 6591 if (!Getter || Getter->isSynthesizedAccessorStub()) 6592 CodeGenFunction(*this).GenerateObjCGetter( 6593 const_cast<ObjCImplementationDecl *>(D), PID); 6594 auto *Setter = PID->getSetterMethodDecl(); 6595 if (!PD->isReadOnly() && (!Setter || Setter->isSynthesizedAccessorStub())) 6596 CodeGenFunction(*this).GenerateObjCSetter( 6597 const_cast<ObjCImplementationDecl *>(D), PID); 6598 } 6599 } 6600 } 6601 6602 static bool needsDestructMethod(ObjCImplementationDecl *impl) { 6603 const ObjCInterfaceDecl *iface = impl->getClassInterface(); 6604 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin(); 6605 ivar; ivar = ivar->getNextIvar()) 6606 if (ivar->getType().isDestructedType()) 6607 return true; 6608 6609 return false; 6610 } 6611 6612 static bool AllTrivialInitializers(CodeGenModule &CGM, 6613 ObjCImplementationDecl *D) { 6614 CodeGenFunction CGF(CGM); 6615 for (ObjCImplementationDecl::init_iterator B = D->init_begin(), 6616 E = D->init_end(); B != E; ++B) { 6617 CXXCtorInitializer *CtorInitExp = *B; 6618 Expr *Init = CtorInitExp->getInit(); 6619 if (!CGF.isTrivialInitializer(Init)) 6620 return false; 6621 } 6622 return true; 6623 } 6624 6625 /// EmitObjCIvarInitializations - Emit information for ivar initialization 6626 /// for an implementation. 6627 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) { 6628 // We might need a .cxx_destruct even if we don't have any ivar initializers. 6629 if (needsDestructMethod(D)) { 6630 const IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct"); 6631 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 6632 ObjCMethodDecl *DTORMethod = ObjCMethodDecl::Create( 6633 getContext(), D->getLocation(), D->getLocation(), cxxSelector, 6634 getContext().VoidTy, nullptr, D, 6635 /*isInstance=*/true, /*isVariadic=*/false, 6636 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false, 6637 /*isImplicitlyDeclared=*/true, 6638 /*isDefined=*/false, ObjCImplementationControl::Required); 6639 D->addInstanceMethod(DTORMethod); 6640 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false); 6641 D->setHasDestructors(true); 6642 } 6643 6644 // If the implementation doesn't have any ivar initializers, we don't need 6645 // a .cxx_construct. 6646 if (D->getNumIvarInitializers() == 0 || 6647 AllTrivialInitializers(*this, D)) 6648 return; 6649 6650 const IdentifierInfo *II = &getContext().Idents.get(".cxx_construct"); 6651 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 6652 // The constructor returns 'self'. 6653 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create( 6654 getContext(), D->getLocation(), D->getLocation(), cxxSelector, 6655 getContext().getObjCIdType(), nullptr, D, /*isInstance=*/true, 6656 /*isVariadic=*/false, 6657 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false, 6658 /*isImplicitlyDeclared=*/true, 6659 /*isDefined=*/false, ObjCImplementationControl::Required); 6660 D->addInstanceMethod(CTORMethod); 6661 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true); 6662 D->setHasNonZeroConstructors(true); 6663 } 6664 6665 // EmitLinkageSpec - Emit all declarations in a linkage spec. 6666 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) { 6667 if (LSD->getLanguage() != LinkageSpecLanguageIDs::C && 6668 LSD->getLanguage() != LinkageSpecLanguageIDs::CXX) { 6669 ErrorUnsupported(LSD, "linkage spec"); 6670 return; 6671 } 6672 6673 EmitDeclContext(LSD); 6674 } 6675 6676 void CodeGenModule::EmitTopLevelStmt(const TopLevelStmtDecl *D) { 6677 // Device code should not be at top level. 6678 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) 6679 return; 6680 6681 std::unique_ptr<CodeGenFunction> &CurCGF = 6682 GlobalTopLevelStmtBlockInFlight.first; 6683 6684 // We emitted a top-level stmt but after it there is initialization. 6685 // Stop squashing the top-level stmts into a single function. 6686 if (CurCGF && CXXGlobalInits.back() != CurCGF->CurFn) { 6687 CurCGF->FinishFunction(D->getEndLoc()); 6688 CurCGF = nullptr; 6689 } 6690 6691 if (!CurCGF) { 6692 // void __stmts__N(void) 6693 // FIXME: Ask the ABI name mangler to pick a name. 6694 std::string Name = "__stmts__" + llvm::utostr(CXXGlobalInits.size()); 6695 FunctionArgList Args; 6696 QualType RetTy = getContext().VoidTy; 6697 const CGFunctionInfo &FnInfo = 6698 getTypes().arrangeBuiltinFunctionDeclaration(RetTy, Args); 6699 llvm::FunctionType *FnTy = getTypes().GetFunctionType(FnInfo); 6700 llvm::Function *Fn = llvm::Function::Create( 6701 FnTy, llvm::GlobalValue::InternalLinkage, Name, &getModule()); 6702 6703 CurCGF.reset(new CodeGenFunction(*this)); 6704 GlobalTopLevelStmtBlockInFlight.second = D; 6705 CurCGF->StartFunction(GlobalDecl(), RetTy, Fn, FnInfo, Args, 6706 D->getBeginLoc(), D->getBeginLoc()); 6707 CXXGlobalInits.push_back(Fn); 6708 } 6709 6710 CurCGF->EmitStmt(D->getStmt()); 6711 } 6712 6713 void CodeGenModule::EmitDeclContext(const DeclContext *DC) { 6714 for (auto *I : DC->decls()) { 6715 // Unlike other DeclContexts, the contents of an ObjCImplDecl at TU scope 6716 // are themselves considered "top-level", so EmitTopLevelDecl on an 6717 // ObjCImplDecl does not recursively visit them. We need to do that in 6718 // case they're nested inside another construct (LinkageSpecDecl / 6719 // ExportDecl) that does stop them from being considered "top-level". 6720 if (auto *OID = dyn_cast<ObjCImplDecl>(I)) { 6721 for (auto *M : OID->methods()) 6722 EmitTopLevelDecl(M); 6723 } 6724 6725 EmitTopLevelDecl(I); 6726 } 6727 } 6728 6729 /// EmitTopLevelDecl - Emit code for a single top level declaration. 6730 void CodeGenModule::EmitTopLevelDecl(Decl *D) { 6731 // Ignore dependent declarations. 6732 if (D->isTemplated()) 6733 return; 6734 6735 // Consteval function shouldn't be emitted. 6736 if (auto *FD = dyn_cast<FunctionDecl>(D); FD && FD->isImmediateFunction()) 6737 return; 6738 6739 switch (D->getKind()) { 6740 case Decl::CXXConversion: 6741 case Decl::CXXMethod: 6742 case Decl::Function: 6743 EmitGlobal(cast<FunctionDecl>(D)); 6744 // Always provide some coverage mapping 6745 // even for the functions that aren't emitted. 6746 AddDeferredUnusedCoverageMapping(D); 6747 break; 6748 6749 case Decl::CXXDeductionGuide: 6750 // Function-like, but does not result in code emission. 6751 break; 6752 6753 case Decl::Var: 6754 case Decl::Decomposition: 6755 case Decl::VarTemplateSpecialization: 6756 EmitGlobal(cast<VarDecl>(D)); 6757 if (auto *DD = dyn_cast<DecompositionDecl>(D)) 6758 for (auto *B : DD->bindings()) 6759 if (auto *HD = B->getHoldingVar()) 6760 EmitGlobal(HD); 6761 break; 6762 6763 // Indirect fields from global anonymous structs and unions can be 6764 // ignored; only the actual variable requires IR gen support. 6765 case Decl::IndirectField: 6766 break; 6767 6768 // C++ Decls 6769 case Decl::Namespace: 6770 EmitDeclContext(cast<NamespaceDecl>(D)); 6771 break; 6772 case Decl::ClassTemplateSpecialization: { 6773 const auto *Spec = cast<ClassTemplateSpecializationDecl>(D); 6774 if (CGDebugInfo *DI = getModuleDebugInfo()) 6775 if (Spec->getSpecializationKind() == 6776 TSK_ExplicitInstantiationDefinition && 6777 Spec->hasDefinition()) 6778 DI->completeTemplateDefinition(*Spec); 6779 } [[fallthrough]]; 6780 case Decl::CXXRecord: { 6781 CXXRecordDecl *CRD = cast<CXXRecordDecl>(D); 6782 if (CGDebugInfo *DI = getModuleDebugInfo()) { 6783 if (CRD->hasDefinition()) 6784 DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D))); 6785 if (auto *ES = D->getASTContext().getExternalSource()) 6786 if (ES->hasExternalDefinitions(D) == ExternalASTSource::EK_Never) 6787 DI->completeUnusedClass(*CRD); 6788 } 6789 // Emit any static data members, they may be definitions. 6790 for (auto *I : CRD->decls()) 6791 if (isa<VarDecl>(I) || isa<CXXRecordDecl>(I)) 6792 EmitTopLevelDecl(I); 6793 break; 6794 } 6795 // No code generation needed. 6796 case Decl::UsingShadow: 6797 case Decl::ClassTemplate: 6798 case Decl::VarTemplate: 6799 case Decl::Concept: 6800 case Decl::VarTemplatePartialSpecialization: 6801 case Decl::FunctionTemplate: 6802 case Decl::TypeAliasTemplate: 6803 case Decl::Block: 6804 case Decl::Empty: 6805 case Decl::Binding: 6806 break; 6807 case Decl::Using: // using X; [C++] 6808 if (CGDebugInfo *DI = getModuleDebugInfo()) 6809 DI->EmitUsingDecl(cast<UsingDecl>(*D)); 6810 break; 6811 case Decl::UsingEnum: // using enum X; [C++] 6812 if (CGDebugInfo *DI = getModuleDebugInfo()) 6813 DI->EmitUsingEnumDecl(cast<UsingEnumDecl>(*D)); 6814 break; 6815 case Decl::NamespaceAlias: 6816 if (CGDebugInfo *DI = getModuleDebugInfo()) 6817 DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(*D)); 6818 break; 6819 case Decl::UsingDirective: // using namespace X; [C++] 6820 if (CGDebugInfo *DI = getModuleDebugInfo()) 6821 DI->EmitUsingDirective(cast<UsingDirectiveDecl>(*D)); 6822 break; 6823 case Decl::CXXConstructor: 6824 getCXXABI().EmitCXXConstructors(cast<CXXConstructorDecl>(D)); 6825 break; 6826 case Decl::CXXDestructor: 6827 getCXXABI().EmitCXXDestructors(cast<CXXDestructorDecl>(D)); 6828 break; 6829 6830 case Decl::StaticAssert: 6831 // Nothing to do. 6832 break; 6833 6834 // Objective-C Decls 6835 6836 // Forward declarations, no (immediate) code generation. 6837 case Decl::ObjCInterface: 6838 case Decl::ObjCCategory: 6839 break; 6840 6841 case Decl::ObjCProtocol: { 6842 auto *Proto = cast<ObjCProtocolDecl>(D); 6843 if (Proto->isThisDeclarationADefinition()) 6844 ObjCRuntime->GenerateProtocol(Proto); 6845 break; 6846 } 6847 6848 case Decl::ObjCCategoryImpl: 6849 // Categories have properties but don't support synthesize so we 6850 // can ignore them here. 6851 ObjCRuntime->GenerateCategory(cast<ObjCCategoryImplDecl>(D)); 6852 break; 6853 6854 case Decl::ObjCImplementation: { 6855 auto *OMD = cast<ObjCImplementationDecl>(D); 6856 EmitObjCPropertyImplementations(OMD); 6857 EmitObjCIvarInitializations(OMD); 6858 ObjCRuntime->GenerateClass(OMD); 6859 // Emit global variable debug information. 6860 if (CGDebugInfo *DI = getModuleDebugInfo()) 6861 if (getCodeGenOpts().hasReducedDebugInfo()) 6862 DI->getOrCreateInterfaceType(getContext().getObjCInterfaceType( 6863 OMD->getClassInterface()), OMD->getLocation()); 6864 break; 6865 } 6866 case Decl::ObjCMethod: { 6867 auto *OMD = cast<ObjCMethodDecl>(D); 6868 // If this is not a prototype, emit the body. 6869 if (OMD->getBody()) 6870 CodeGenFunction(*this).GenerateObjCMethod(OMD); 6871 break; 6872 } 6873 case Decl::ObjCCompatibleAlias: 6874 ObjCRuntime->RegisterAlias(cast<ObjCCompatibleAliasDecl>(D)); 6875 break; 6876 6877 case Decl::PragmaComment: { 6878 const auto *PCD = cast<PragmaCommentDecl>(D); 6879 switch (PCD->getCommentKind()) { 6880 case PCK_Unknown: 6881 llvm_unreachable("unexpected pragma comment kind"); 6882 case PCK_Linker: 6883 AppendLinkerOptions(PCD->getArg()); 6884 break; 6885 case PCK_Lib: 6886 AddDependentLib(PCD->getArg()); 6887 break; 6888 case PCK_Compiler: 6889 case PCK_ExeStr: 6890 case PCK_User: 6891 break; // We ignore all of these. 6892 } 6893 break; 6894 } 6895 6896 case Decl::PragmaDetectMismatch: { 6897 const auto *PDMD = cast<PragmaDetectMismatchDecl>(D); 6898 AddDetectMismatch(PDMD->getName(), PDMD->getValue()); 6899 break; 6900 } 6901 6902 case Decl::LinkageSpec: 6903 EmitLinkageSpec(cast<LinkageSpecDecl>(D)); 6904 break; 6905 6906 case Decl::FileScopeAsm: { 6907 // File-scope asm is ignored during device-side CUDA compilation. 6908 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) 6909 break; 6910 // File-scope asm is ignored during device-side OpenMP compilation. 6911 if (LangOpts.OpenMPIsTargetDevice) 6912 break; 6913 // File-scope asm is ignored during device-side SYCL compilation. 6914 if (LangOpts.SYCLIsDevice) 6915 break; 6916 auto *AD = cast<FileScopeAsmDecl>(D); 6917 getModule().appendModuleInlineAsm(AD->getAsmString()->getString()); 6918 break; 6919 } 6920 6921 case Decl::TopLevelStmt: 6922 EmitTopLevelStmt(cast<TopLevelStmtDecl>(D)); 6923 break; 6924 6925 case Decl::Import: { 6926 auto *Import = cast<ImportDecl>(D); 6927 6928 // If we've already imported this module, we're done. 6929 if (!ImportedModules.insert(Import->getImportedModule())) 6930 break; 6931 6932 // Emit debug information for direct imports. 6933 if (!Import->getImportedOwningModule()) { 6934 if (CGDebugInfo *DI = getModuleDebugInfo()) 6935 DI->EmitImportDecl(*Import); 6936 } 6937 6938 // For C++ standard modules we are done - we will call the module 6939 // initializer for imported modules, and that will likewise call those for 6940 // any imports it has. 6941 if (CXX20ModuleInits && Import->getImportedOwningModule() && 6942 !Import->getImportedOwningModule()->isModuleMapModule()) 6943 break; 6944 6945 // For clang C++ module map modules the initializers for sub-modules are 6946 // emitted here. 6947 6948 // Find all of the submodules and emit the module initializers. 6949 llvm::SmallPtrSet<clang::Module *, 16> Visited; 6950 SmallVector<clang::Module *, 16> Stack; 6951 Visited.insert(Import->getImportedModule()); 6952 Stack.push_back(Import->getImportedModule()); 6953 6954 while (!Stack.empty()) { 6955 clang::Module *Mod = Stack.pop_back_val(); 6956 if (!EmittedModuleInitializers.insert(Mod).second) 6957 continue; 6958 6959 for (auto *D : Context.getModuleInitializers(Mod)) 6960 EmitTopLevelDecl(D); 6961 6962 // Visit the submodules of this module. 6963 for (auto *Submodule : Mod->submodules()) { 6964 // Skip explicit children; they need to be explicitly imported to emit 6965 // the initializers. 6966 if (Submodule->IsExplicit) 6967 continue; 6968 6969 if (Visited.insert(Submodule).second) 6970 Stack.push_back(Submodule); 6971 } 6972 } 6973 break; 6974 } 6975 6976 case Decl::Export: 6977 EmitDeclContext(cast<ExportDecl>(D)); 6978 break; 6979 6980 case Decl::OMPThreadPrivate: 6981 EmitOMPThreadPrivateDecl(cast<OMPThreadPrivateDecl>(D)); 6982 break; 6983 6984 case Decl::OMPAllocate: 6985 EmitOMPAllocateDecl(cast<OMPAllocateDecl>(D)); 6986 break; 6987 6988 case Decl::OMPDeclareReduction: 6989 EmitOMPDeclareReduction(cast<OMPDeclareReductionDecl>(D)); 6990 break; 6991 6992 case Decl::OMPDeclareMapper: 6993 EmitOMPDeclareMapper(cast<OMPDeclareMapperDecl>(D)); 6994 break; 6995 6996 case Decl::OMPRequires: 6997 EmitOMPRequiresDecl(cast<OMPRequiresDecl>(D)); 6998 break; 6999 7000 case Decl::Typedef: 7001 case Decl::TypeAlias: // using foo = bar; [C++11] 7002 if (CGDebugInfo *DI = getModuleDebugInfo()) 7003 DI->EmitAndRetainType( 7004 getContext().getTypedefType(cast<TypedefNameDecl>(D))); 7005 break; 7006 7007 case Decl::Record: 7008 if (CGDebugInfo *DI = getModuleDebugInfo()) 7009 if (cast<RecordDecl>(D)->getDefinition()) 7010 DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D))); 7011 break; 7012 7013 case Decl::Enum: 7014 if (CGDebugInfo *DI = getModuleDebugInfo()) 7015 if (cast<EnumDecl>(D)->getDefinition()) 7016 DI->EmitAndRetainType(getContext().getEnumType(cast<EnumDecl>(D))); 7017 break; 7018 7019 case Decl::HLSLBuffer: 7020 getHLSLRuntime().addBuffer(cast<HLSLBufferDecl>(D)); 7021 break; 7022 7023 default: 7024 // Make sure we handled everything we should, every other kind is a 7025 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind 7026 // function. Need to recode Decl::Kind to do that easily. 7027 assert(isa<TypeDecl>(D) && "Unsupported decl kind"); 7028 break; 7029 } 7030 } 7031 7032 void CodeGenModule::AddDeferredUnusedCoverageMapping(Decl *D) { 7033 // Do we need to generate coverage mapping? 7034 if (!CodeGenOpts.CoverageMapping) 7035 return; 7036 switch (D->getKind()) { 7037 case Decl::CXXConversion: 7038 case Decl::CXXMethod: 7039 case Decl::Function: 7040 case Decl::ObjCMethod: 7041 case Decl::CXXConstructor: 7042 case Decl::CXXDestructor: { 7043 if (!cast<FunctionDecl>(D)->doesThisDeclarationHaveABody()) 7044 break; 7045 SourceManager &SM = getContext().getSourceManager(); 7046 if (LimitedCoverage && SM.getMainFileID() != SM.getFileID(D->getBeginLoc())) 7047 break; 7048 DeferredEmptyCoverageMappingDecls.try_emplace(D, true); 7049 break; 7050 } 7051 default: 7052 break; 7053 }; 7054 } 7055 7056 void CodeGenModule::ClearUnusedCoverageMapping(const Decl *D) { 7057 // Do we need to generate coverage mapping? 7058 if (!CodeGenOpts.CoverageMapping) 7059 return; 7060 if (const auto *Fn = dyn_cast<FunctionDecl>(D)) { 7061 if (Fn->isTemplateInstantiation()) 7062 ClearUnusedCoverageMapping(Fn->getTemplateInstantiationPattern()); 7063 } 7064 DeferredEmptyCoverageMappingDecls.insert_or_assign(D, false); 7065 } 7066 7067 void CodeGenModule::EmitDeferredUnusedCoverageMappings() { 7068 // We call takeVector() here to avoid use-after-free. 7069 // FIXME: DeferredEmptyCoverageMappingDecls is getting mutated because 7070 // we deserialize function bodies to emit coverage info for them, and that 7071 // deserializes more declarations. How should we handle that case? 7072 for (const auto &Entry : DeferredEmptyCoverageMappingDecls.takeVector()) { 7073 if (!Entry.second) 7074 continue; 7075 const Decl *D = Entry.first; 7076 switch (D->getKind()) { 7077 case Decl::CXXConversion: 7078 case Decl::CXXMethod: 7079 case Decl::Function: 7080 case Decl::ObjCMethod: { 7081 CodeGenPGO PGO(*this); 7082 GlobalDecl GD(cast<FunctionDecl>(D)); 7083 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 7084 getFunctionLinkage(GD)); 7085 break; 7086 } 7087 case Decl::CXXConstructor: { 7088 CodeGenPGO PGO(*this); 7089 GlobalDecl GD(cast<CXXConstructorDecl>(D), Ctor_Base); 7090 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 7091 getFunctionLinkage(GD)); 7092 break; 7093 } 7094 case Decl::CXXDestructor: { 7095 CodeGenPGO PGO(*this); 7096 GlobalDecl GD(cast<CXXDestructorDecl>(D), Dtor_Base); 7097 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 7098 getFunctionLinkage(GD)); 7099 break; 7100 } 7101 default: 7102 break; 7103 }; 7104 } 7105 } 7106 7107 void CodeGenModule::EmitMainVoidAlias() { 7108 // In order to transition away from "__original_main" gracefully, emit an 7109 // alias for "main" in the no-argument case so that libc can detect when 7110 // new-style no-argument main is in used. 7111 if (llvm::Function *F = getModule().getFunction("main")) { 7112 if (!F->isDeclaration() && F->arg_size() == 0 && !F->isVarArg() && 7113 F->getReturnType()->isIntegerTy(Context.getTargetInfo().getIntWidth())) { 7114 auto *GA = llvm::GlobalAlias::create("__main_void", F); 7115 GA->setVisibility(llvm::GlobalValue::HiddenVisibility); 7116 } 7117 } 7118 } 7119 7120 /// Turns the given pointer into a constant. 7121 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context, 7122 const void *Ptr) { 7123 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr); 7124 llvm::Type *i64 = llvm::Type::getInt64Ty(Context); 7125 return llvm::ConstantInt::get(i64, PtrInt); 7126 } 7127 7128 static void EmitGlobalDeclMetadata(CodeGenModule &CGM, 7129 llvm::NamedMDNode *&GlobalMetadata, 7130 GlobalDecl D, 7131 llvm::GlobalValue *Addr) { 7132 if (!GlobalMetadata) 7133 GlobalMetadata = 7134 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs"); 7135 7136 // TODO: should we report variant information for ctors/dtors? 7137 llvm::Metadata *Ops[] = {llvm::ConstantAsMetadata::get(Addr), 7138 llvm::ConstantAsMetadata::get(GetPointerConstant( 7139 CGM.getLLVMContext(), D.getDecl()))}; 7140 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops)); 7141 } 7142 7143 bool CodeGenModule::CheckAndReplaceExternCIFuncs(llvm::GlobalValue *Elem, 7144 llvm::GlobalValue *CppFunc) { 7145 // Store the list of ifuncs we need to replace uses in. 7146 llvm::SmallVector<llvm::GlobalIFunc *> IFuncs; 7147 // List of ConstantExprs that we should be able to delete when we're done 7148 // here. 7149 llvm::SmallVector<llvm::ConstantExpr *> CEs; 7150 7151 // It isn't valid to replace the extern-C ifuncs if all we find is itself! 7152 if (Elem == CppFunc) 7153 return false; 7154 7155 // First make sure that all users of this are ifuncs (or ifuncs via a 7156 // bitcast), and collect the list of ifuncs and CEs so we can work on them 7157 // later. 7158 for (llvm::User *User : Elem->users()) { 7159 // Users can either be a bitcast ConstExpr that is used by the ifuncs, OR an 7160 // ifunc directly. In any other case, just give up, as we don't know what we 7161 // could break by changing those. 7162 if (auto *ConstExpr = dyn_cast<llvm::ConstantExpr>(User)) { 7163 if (ConstExpr->getOpcode() != llvm::Instruction::BitCast) 7164 return false; 7165 7166 for (llvm::User *CEUser : ConstExpr->users()) { 7167 if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(CEUser)) { 7168 IFuncs.push_back(IFunc); 7169 } else { 7170 return false; 7171 } 7172 } 7173 CEs.push_back(ConstExpr); 7174 } else if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(User)) { 7175 IFuncs.push_back(IFunc); 7176 } else { 7177 // This user is one we don't know how to handle, so fail redirection. This 7178 // will result in an ifunc retaining a resolver name that will ultimately 7179 // fail to be resolved to a defined function. 7180 return false; 7181 } 7182 } 7183 7184 // Now we know this is a valid case where we can do this alias replacement, we 7185 // need to remove all of the references to Elem (and the bitcasts!) so we can 7186 // delete it. 7187 for (llvm::GlobalIFunc *IFunc : IFuncs) 7188 IFunc->setResolver(nullptr); 7189 for (llvm::ConstantExpr *ConstExpr : CEs) 7190 ConstExpr->destroyConstant(); 7191 7192 // We should now be out of uses for the 'old' version of this function, so we 7193 // can erase it as well. 7194 Elem->eraseFromParent(); 7195 7196 for (llvm::GlobalIFunc *IFunc : IFuncs) { 7197 // The type of the resolver is always just a function-type that returns the 7198 // type of the IFunc, so create that here. If the type of the actual 7199 // resolver doesn't match, it just gets bitcast to the right thing. 7200 auto *ResolverTy = 7201 llvm::FunctionType::get(IFunc->getType(), /*isVarArg*/ false); 7202 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 7203 CppFunc->getName(), ResolverTy, {}, /*ForVTable*/ false); 7204 IFunc->setResolver(Resolver); 7205 } 7206 return true; 7207 } 7208 7209 /// For each function which is declared within an extern "C" region and marked 7210 /// as 'used', but has internal linkage, create an alias from the unmangled 7211 /// name to the mangled name if possible. People expect to be able to refer 7212 /// to such functions with an unmangled name from inline assembly within the 7213 /// same translation unit. 7214 void CodeGenModule::EmitStaticExternCAliases() { 7215 if (!getTargetCodeGenInfo().shouldEmitStaticExternCAliases()) 7216 return; 7217 for (auto &I : StaticExternCValues) { 7218 const IdentifierInfo *Name = I.first; 7219 llvm::GlobalValue *Val = I.second; 7220 7221 // If Val is null, that implies there were multiple declarations that each 7222 // had a claim to the unmangled name. In this case, generation of the alias 7223 // is suppressed. See CodeGenModule::MaybeHandleStaticInExternC. 7224 if (!Val) 7225 break; 7226 7227 llvm::GlobalValue *ExistingElem = 7228 getModule().getNamedValue(Name->getName()); 7229 7230 // If there is either not something already by this name, or we were able to 7231 // replace all uses from IFuncs, create the alias. 7232 if (!ExistingElem || CheckAndReplaceExternCIFuncs(ExistingElem, Val)) 7233 addCompilerUsedGlobal(llvm::GlobalAlias::create(Name->getName(), Val)); 7234 } 7235 } 7236 7237 bool CodeGenModule::lookupRepresentativeDecl(StringRef MangledName, 7238 GlobalDecl &Result) const { 7239 auto Res = Manglings.find(MangledName); 7240 if (Res == Manglings.end()) 7241 return false; 7242 Result = Res->getValue(); 7243 return true; 7244 } 7245 7246 /// Emits metadata nodes associating all the global values in the 7247 /// current module with the Decls they came from. This is useful for 7248 /// projects using IR gen as a subroutine. 7249 /// 7250 /// Since there's currently no way to associate an MDNode directly 7251 /// with an llvm::GlobalValue, we create a global named metadata 7252 /// with the name 'clang.global.decl.ptrs'. 7253 void CodeGenModule::EmitDeclMetadata() { 7254 llvm::NamedMDNode *GlobalMetadata = nullptr; 7255 7256 for (auto &I : MangledDeclNames) { 7257 llvm::GlobalValue *Addr = getModule().getNamedValue(I.second); 7258 // Some mangled names don't necessarily have an associated GlobalValue 7259 // in this module, e.g. if we mangled it for DebugInfo. 7260 if (Addr) 7261 EmitGlobalDeclMetadata(*this, GlobalMetadata, I.first, Addr); 7262 } 7263 } 7264 7265 /// Emits metadata nodes for all the local variables in the current 7266 /// function. 7267 void CodeGenFunction::EmitDeclMetadata() { 7268 if (LocalDeclMap.empty()) return; 7269 7270 llvm::LLVMContext &Context = getLLVMContext(); 7271 7272 // Find the unique metadata ID for this name. 7273 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr"); 7274 7275 llvm::NamedMDNode *GlobalMetadata = nullptr; 7276 7277 for (auto &I : LocalDeclMap) { 7278 const Decl *D = I.first; 7279 llvm::Value *Addr = I.second.emitRawPointer(*this); 7280 if (auto *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) { 7281 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D); 7282 Alloca->setMetadata( 7283 DeclPtrKind, llvm::MDNode::get( 7284 Context, llvm::ValueAsMetadata::getConstant(DAddr))); 7285 } else if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr)) { 7286 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D)); 7287 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV); 7288 } 7289 } 7290 } 7291 7292 void CodeGenModule::EmitVersionIdentMetadata() { 7293 llvm::NamedMDNode *IdentMetadata = 7294 TheModule.getOrInsertNamedMetadata("llvm.ident"); 7295 std::string Version = getClangFullVersion(); 7296 llvm::LLVMContext &Ctx = TheModule.getContext(); 7297 7298 llvm::Metadata *IdentNode[] = {llvm::MDString::get(Ctx, Version)}; 7299 IdentMetadata->addOperand(llvm::MDNode::get(Ctx, IdentNode)); 7300 } 7301 7302 void CodeGenModule::EmitCommandLineMetadata() { 7303 llvm::NamedMDNode *CommandLineMetadata = 7304 TheModule.getOrInsertNamedMetadata("llvm.commandline"); 7305 std::string CommandLine = getCodeGenOpts().RecordCommandLine; 7306 llvm::LLVMContext &Ctx = TheModule.getContext(); 7307 7308 llvm::Metadata *CommandLineNode[] = {llvm::MDString::get(Ctx, CommandLine)}; 7309 CommandLineMetadata->addOperand(llvm::MDNode::get(Ctx, CommandLineNode)); 7310 } 7311 7312 void CodeGenModule::EmitCoverageFile() { 7313 llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu"); 7314 if (!CUNode) 7315 return; 7316 7317 llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov"); 7318 llvm::LLVMContext &Ctx = TheModule.getContext(); 7319 auto *CoverageDataFile = 7320 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageDataFile); 7321 auto *CoverageNotesFile = 7322 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageNotesFile); 7323 for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) { 7324 llvm::MDNode *CU = CUNode->getOperand(i); 7325 llvm::Metadata *Elts[] = {CoverageNotesFile, CoverageDataFile, CU}; 7326 GCov->addOperand(llvm::MDNode::get(Ctx, Elts)); 7327 } 7328 } 7329 7330 llvm::Constant *CodeGenModule::GetAddrOfRTTIDescriptor(QualType Ty, 7331 bool ForEH) { 7332 // Return a bogus pointer if RTTI is disabled, unless it's for EH. 7333 // FIXME: should we even be calling this method if RTTI is disabled 7334 // and it's not for EH? 7335 if (!shouldEmitRTTI(ForEH)) 7336 return llvm::Constant::getNullValue(GlobalsInt8PtrTy); 7337 7338 if (ForEH && Ty->isObjCObjectPointerType() && 7339 LangOpts.ObjCRuntime.isGNUFamily()) 7340 return ObjCRuntime->GetEHType(Ty); 7341 7342 return getCXXABI().getAddrOfRTTIDescriptor(Ty); 7343 } 7344 7345 void CodeGenModule::EmitOMPThreadPrivateDecl(const OMPThreadPrivateDecl *D) { 7346 // Do not emit threadprivates in simd-only mode. 7347 if (LangOpts.OpenMP && LangOpts.OpenMPSimd) 7348 return; 7349 for (auto RefExpr : D->varlists()) { 7350 auto *VD = cast<VarDecl>(cast<DeclRefExpr>(RefExpr)->getDecl()); 7351 bool PerformInit = 7352 VD->getAnyInitializer() && 7353 !VD->getAnyInitializer()->isConstantInitializer(getContext(), 7354 /*ForRef=*/false); 7355 7356 Address Addr(GetAddrOfGlobalVar(VD), 7357 getTypes().ConvertTypeForMem(VD->getType()), 7358 getContext().getDeclAlign(VD)); 7359 if (auto InitFunction = getOpenMPRuntime().emitThreadPrivateVarDefinition( 7360 VD, Addr, RefExpr->getBeginLoc(), PerformInit)) 7361 CXXGlobalInits.push_back(InitFunction); 7362 } 7363 } 7364 7365 llvm::Metadata * 7366 CodeGenModule::CreateMetadataIdentifierImpl(QualType T, MetadataTypeMap &Map, 7367 StringRef Suffix) { 7368 if (auto *FnType = T->getAs<FunctionProtoType>()) 7369 T = getContext().getFunctionType( 7370 FnType->getReturnType(), FnType->getParamTypes(), 7371 FnType->getExtProtoInfo().withExceptionSpec(EST_None)); 7372 7373 llvm::Metadata *&InternalId = Map[T.getCanonicalType()]; 7374 if (InternalId) 7375 return InternalId; 7376 7377 if (isExternallyVisible(T->getLinkage())) { 7378 std::string OutName; 7379 llvm::raw_string_ostream Out(OutName); 7380 getCXXABI().getMangleContext().mangleCanonicalTypeName( 7381 T, Out, getCodeGenOpts().SanitizeCfiICallNormalizeIntegers); 7382 7383 if (getCodeGenOpts().SanitizeCfiICallNormalizeIntegers) 7384 Out << ".normalized"; 7385 7386 Out << Suffix; 7387 7388 InternalId = llvm::MDString::get(getLLVMContext(), Out.str()); 7389 } else { 7390 InternalId = llvm::MDNode::getDistinct(getLLVMContext(), 7391 llvm::ArrayRef<llvm::Metadata *>()); 7392 } 7393 7394 return InternalId; 7395 } 7396 7397 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierForType(QualType T) { 7398 return CreateMetadataIdentifierImpl(T, MetadataIdMap, ""); 7399 } 7400 7401 llvm::Metadata * 7402 CodeGenModule::CreateMetadataIdentifierForVirtualMemPtrType(QualType T) { 7403 return CreateMetadataIdentifierImpl(T, VirtualMetadataIdMap, ".virtual"); 7404 } 7405 7406 // Generalize pointer types to a void pointer with the qualifiers of the 7407 // originally pointed-to type, e.g. 'const char *' and 'char * const *' 7408 // generalize to 'const void *' while 'char *' and 'const char **' generalize to 7409 // 'void *'. 7410 static QualType GeneralizeType(ASTContext &Ctx, QualType Ty) { 7411 if (!Ty->isPointerType()) 7412 return Ty; 7413 7414 return Ctx.getPointerType( 7415 QualType(Ctx.VoidTy).withCVRQualifiers( 7416 Ty->getPointeeType().getCVRQualifiers())); 7417 } 7418 7419 // Apply type generalization to a FunctionType's return and argument types 7420 static QualType GeneralizeFunctionType(ASTContext &Ctx, QualType Ty) { 7421 if (auto *FnType = Ty->getAs<FunctionProtoType>()) { 7422 SmallVector<QualType, 8> GeneralizedParams; 7423 for (auto &Param : FnType->param_types()) 7424 GeneralizedParams.push_back(GeneralizeType(Ctx, Param)); 7425 7426 return Ctx.getFunctionType( 7427 GeneralizeType(Ctx, FnType->getReturnType()), 7428 GeneralizedParams, FnType->getExtProtoInfo()); 7429 } 7430 7431 if (auto *FnType = Ty->getAs<FunctionNoProtoType>()) 7432 return Ctx.getFunctionNoProtoType( 7433 GeneralizeType(Ctx, FnType->getReturnType())); 7434 7435 llvm_unreachable("Encountered unknown FunctionType"); 7436 } 7437 7438 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierGeneralized(QualType T) { 7439 return CreateMetadataIdentifierImpl(GeneralizeFunctionType(getContext(), T), 7440 GeneralizedMetadataIdMap, ".generalized"); 7441 } 7442 7443 /// Returns whether this module needs the "all-vtables" type identifier. 7444 bool CodeGenModule::NeedAllVtablesTypeId() const { 7445 // Returns true if at least one of vtable-based CFI checkers is enabled and 7446 // is not in the trapping mode. 7447 return ((LangOpts.Sanitize.has(SanitizerKind::CFIVCall) && 7448 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIVCall)) || 7449 (LangOpts.Sanitize.has(SanitizerKind::CFINVCall) && 7450 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFINVCall)) || 7451 (LangOpts.Sanitize.has(SanitizerKind::CFIDerivedCast) && 7452 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIDerivedCast)) || 7453 (LangOpts.Sanitize.has(SanitizerKind::CFIUnrelatedCast) && 7454 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIUnrelatedCast))); 7455 } 7456 7457 void CodeGenModule::AddVTableTypeMetadata(llvm::GlobalVariable *VTable, 7458 CharUnits Offset, 7459 const CXXRecordDecl *RD) { 7460 llvm::Metadata *MD = 7461 CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0)); 7462 VTable->addTypeMetadata(Offset.getQuantity(), MD); 7463 7464 if (CodeGenOpts.SanitizeCfiCrossDso) 7465 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD)) 7466 VTable->addTypeMetadata(Offset.getQuantity(), 7467 llvm::ConstantAsMetadata::get(CrossDsoTypeId)); 7468 7469 if (NeedAllVtablesTypeId()) { 7470 llvm::Metadata *MD = llvm::MDString::get(getLLVMContext(), "all-vtables"); 7471 VTable->addTypeMetadata(Offset.getQuantity(), MD); 7472 } 7473 } 7474 7475 llvm::SanitizerStatReport &CodeGenModule::getSanStats() { 7476 if (!SanStats) 7477 SanStats = std::make_unique<llvm::SanitizerStatReport>(&getModule()); 7478 7479 return *SanStats; 7480 } 7481 7482 llvm::Value * 7483 CodeGenModule::createOpenCLIntToSamplerConversion(const Expr *E, 7484 CodeGenFunction &CGF) { 7485 llvm::Constant *C = ConstantEmitter(CGF).emitAbstract(E, E->getType()); 7486 auto *SamplerT = getOpenCLRuntime().getSamplerType(E->getType().getTypePtr()); 7487 auto *FTy = llvm::FunctionType::get(SamplerT, {C->getType()}, false); 7488 auto *Call = CGF.EmitRuntimeCall( 7489 CreateRuntimeFunction(FTy, "__translate_sampler_initializer"), {C}); 7490 return Call; 7491 } 7492 7493 CharUnits CodeGenModule::getNaturalPointeeTypeAlignment( 7494 QualType T, LValueBaseInfo *BaseInfo, TBAAAccessInfo *TBAAInfo) { 7495 return getNaturalTypeAlignment(T->getPointeeType(), BaseInfo, TBAAInfo, 7496 /* forPointeeType= */ true); 7497 } 7498 7499 CharUnits CodeGenModule::getNaturalTypeAlignment(QualType T, 7500 LValueBaseInfo *BaseInfo, 7501 TBAAAccessInfo *TBAAInfo, 7502 bool forPointeeType) { 7503 if (TBAAInfo) 7504 *TBAAInfo = getTBAAAccessInfo(T); 7505 7506 // FIXME: This duplicates logic in ASTContext::getTypeAlignIfKnown. But 7507 // that doesn't return the information we need to compute BaseInfo. 7508 7509 // Honor alignment typedef attributes even on incomplete types. 7510 // We also honor them straight for C++ class types, even as pointees; 7511 // there's an expressivity gap here. 7512 if (auto TT = T->getAs<TypedefType>()) { 7513 if (auto Align = TT->getDecl()->getMaxAlignment()) { 7514 if (BaseInfo) 7515 *BaseInfo = LValueBaseInfo(AlignmentSource::AttributedType); 7516 return getContext().toCharUnitsFromBits(Align); 7517 } 7518 } 7519 7520 bool AlignForArray = T->isArrayType(); 7521 7522 // Analyze the base element type, so we don't get confused by incomplete 7523 // array types. 7524 T = getContext().getBaseElementType(T); 7525 7526 if (T->isIncompleteType()) { 7527 // We could try to replicate the logic from 7528 // ASTContext::getTypeAlignIfKnown, but nothing uses the alignment if the 7529 // type is incomplete, so it's impossible to test. We could try to reuse 7530 // getTypeAlignIfKnown, but that doesn't return the information we need 7531 // to set BaseInfo. So just ignore the possibility that the alignment is 7532 // greater than one. 7533 if (BaseInfo) 7534 *BaseInfo = LValueBaseInfo(AlignmentSource::Type); 7535 return CharUnits::One(); 7536 } 7537 7538 if (BaseInfo) 7539 *BaseInfo = LValueBaseInfo(AlignmentSource::Type); 7540 7541 CharUnits Alignment; 7542 const CXXRecordDecl *RD; 7543 if (T.getQualifiers().hasUnaligned()) { 7544 Alignment = CharUnits::One(); 7545 } else if (forPointeeType && !AlignForArray && 7546 (RD = T->getAsCXXRecordDecl())) { 7547 // For C++ class pointees, we don't know whether we're pointing at a 7548 // base or a complete object, so we generally need to use the 7549 // non-virtual alignment. 7550 Alignment = getClassPointerAlignment(RD); 7551 } else { 7552 Alignment = getContext().getTypeAlignInChars(T); 7553 } 7554 7555 // Cap to the global maximum type alignment unless the alignment 7556 // was somehow explicit on the type. 7557 if (unsigned MaxAlign = getLangOpts().MaxTypeAlign) { 7558 if (Alignment.getQuantity() > MaxAlign && 7559 !getContext().isAlignmentRequired(T)) 7560 Alignment = CharUnits::fromQuantity(MaxAlign); 7561 } 7562 return Alignment; 7563 } 7564 7565 bool CodeGenModule::stopAutoInit() { 7566 unsigned StopAfter = getContext().getLangOpts().TrivialAutoVarInitStopAfter; 7567 if (StopAfter) { 7568 // This number is positive only when -ftrivial-auto-var-init-stop-after=* is 7569 // used 7570 if (NumAutoVarInit >= StopAfter) { 7571 return true; 7572 } 7573 if (!NumAutoVarInit) { 7574 unsigned DiagID = getDiags().getCustomDiagID( 7575 DiagnosticsEngine::Warning, 7576 "-ftrivial-auto-var-init-stop-after=%0 has been enabled to limit the " 7577 "number of times ftrivial-auto-var-init=%1 gets applied."); 7578 getDiags().Report(DiagID) 7579 << StopAfter 7580 << (getContext().getLangOpts().getTrivialAutoVarInit() == 7581 LangOptions::TrivialAutoVarInitKind::Zero 7582 ? "zero" 7583 : "pattern"); 7584 } 7585 ++NumAutoVarInit; 7586 } 7587 return false; 7588 } 7589 7590 void CodeGenModule::printPostfixForExternalizedDecl(llvm::raw_ostream &OS, 7591 const Decl *D) const { 7592 // ptxas does not allow '.' in symbol names. On the other hand, HIP prefers 7593 // postfix beginning with '.' since the symbol name can be demangled. 7594 if (LangOpts.HIP) 7595 OS << (isa<VarDecl>(D) ? ".static." : ".intern."); 7596 else 7597 OS << (isa<VarDecl>(D) ? "__static__" : "__intern__"); 7598 7599 // If the CUID is not specified we try to generate a unique postfix. 7600 if (getLangOpts().CUID.empty()) { 7601 SourceManager &SM = getContext().getSourceManager(); 7602 PresumedLoc PLoc = SM.getPresumedLoc(D->getLocation()); 7603 assert(PLoc.isValid() && "Source location is expected to be valid."); 7604 7605 // Get the hash of the user defined macros. 7606 llvm::MD5 Hash; 7607 llvm::MD5::MD5Result Result; 7608 for (const auto &Arg : PreprocessorOpts.Macros) 7609 Hash.update(Arg.first); 7610 Hash.final(Result); 7611 7612 // Get the UniqueID for the file containing the decl. 7613 llvm::sys::fs::UniqueID ID; 7614 if (llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID)) { 7615 PLoc = SM.getPresumedLoc(D->getLocation(), /*UseLineDirectives=*/false); 7616 assert(PLoc.isValid() && "Source location is expected to be valid."); 7617 if (auto EC = llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID)) 7618 SM.getDiagnostics().Report(diag::err_cannot_open_file) 7619 << PLoc.getFilename() << EC.message(); 7620 } 7621 OS << llvm::format("%x", ID.getFile()) << llvm::format("%x", ID.getDevice()) 7622 << "_" << llvm::utohexstr(Result.low(), /*LowerCase=*/true, /*Width=*/8); 7623 } else { 7624 OS << getContext().getCUIDHash(); 7625 } 7626 } 7627 7628 void CodeGenModule::moveLazyEmissionStates(CodeGenModule *NewBuilder) { 7629 assert(DeferredDeclsToEmit.empty() && 7630 "Should have emitted all decls deferred to emit."); 7631 assert(NewBuilder->DeferredDecls.empty() && 7632 "Newly created module should not have deferred decls"); 7633 NewBuilder->DeferredDecls = std::move(DeferredDecls); 7634 assert(EmittedDeferredDecls.empty() && 7635 "Still have (unmerged) EmittedDeferredDecls deferred decls"); 7636 7637 assert(NewBuilder->DeferredVTables.empty() && 7638 "Newly created module should not have deferred vtables"); 7639 NewBuilder->DeferredVTables = std::move(DeferredVTables); 7640 7641 assert(NewBuilder->MangledDeclNames.empty() && 7642 "Newly created module should not have mangled decl names"); 7643 assert(NewBuilder->Manglings.empty() && 7644 "Newly created module should not have manglings"); 7645 NewBuilder->Manglings = std::move(Manglings); 7646 7647 NewBuilder->WeakRefReferences = std::move(WeakRefReferences); 7648 7649 NewBuilder->TBAA = std::move(TBAA); 7650 7651 NewBuilder->ABI->MangleCtx = std::move(ABI->MangleCtx); 7652 } 7653