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 // There are practices to mark template member function as always-inline 3957 // and mark the template as extern explicit instantiation but not give 3958 // the definition for member function. So we have to emit the function 3959 // from explicitly instantiation with always-inline. 3960 // 3961 // See https://github.com/llvm/llvm-project/issues/86893 for details. 3962 // 3963 // TODO: Maybe it is better to give it a warning if we call a non-inline 3964 // function from other module units which is marked as always-inline. 3965 if (!F->isTemplateInstantiation() || !F->hasAttr<AlwaysInlineAttr>()) { 3966 return false; 3967 } 3968 } 3969 3970 if (F->hasAttr<NoInlineAttr>()) 3971 return false; 3972 3973 if (F->hasAttr<DLLImportAttr>() && !F->hasAttr<AlwaysInlineAttr>()) { 3974 // Check whether it would be safe to inline this dllimport function. 3975 DLLImportFunctionVisitor Visitor; 3976 Visitor.TraverseFunctionDecl(const_cast<FunctionDecl*>(F)); 3977 if (!Visitor.SafeToInline) 3978 return false; 3979 3980 if (const CXXDestructorDecl *Dtor = dyn_cast<CXXDestructorDecl>(F)) { 3981 // Implicit destructor invocations aren't captured in the AST, so the 3982 // check above can't see them. Check for them manually here. 3983 for (const Decl *Member : Dtor->getParent()->decls()) 3984 if (isa<FieldDecl>(Member)) 3985 if (HasNonDllImportDtor(cast<FieldDecl>(Member)->getType())) 3986 return false; 3987 for (const CXXBaseSpecifier &B : Dtor->getParent()->bases()) 3988 if (HasNonDllImportDtor(B.getType())) 3989 return false; 3990 } 3991 } 3992 3993 // Inline builtins declaration must be emitted. They often are fortified 3994 // functions. 3995 if (F->isInlineBuiltinDeclaration()) 3996 return true; 3997 3998 // PR9614. Avoid cases where the source code is lying to us. An available 3999 // externally function should have an equivalent function somewhere else, 4000 // but a function that calls itself through asm label/`__builtin_` trickery is 4001 // clearly not equivalent to the real implementation. 4002 // This happens in glibc's btowc and in some configure checks. 4003 return !isTriviallyRecursive(F); 4004 } 4005 4006 bool CodeGenModule::shouldOpportunisticallyEmitVTables() { 4007 return CodeGenOpts.OptimizationLevel > 0; 4008 } 4009 4010 void CodeGenModule::EmitMultiVersionFunctionDefinition(GlobalDecl GD, 4011 llvm::GlobalValue *GV) { 4012 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4013 4014 if (FD->isCPUSpecificMultiVersion()) { 4015 auto *Spec = FD->getAttr<CPUSpecificAttr>(); 4016 for (unsigned I = 0; I < Spec->cpus_size(); ++I) 4017 EmitGlobalFunctionDefinition(GD.getWithMultiVersionIndex(I), nullptr); 4018 } else if (auto *TC = FD->getAttr<TargetClonesAttr>()) { 4019 for (unsigned I = 0; I < TC->featuresStrs_size(); ++I) 4020 // AArch64 favors the default target version over the clone if any. 4021 if ((!TC->isDefaultVersion(I) || !getTarget().getTriple().isAArch64()) && 4022 TC->isFirstOfVersion(I)) 4023 EmitGlobalFunctionDefinition(GD.getWithMultiVersionIndex(I), nullptr); 4024 // Ensure that the resolver function is also emitted. 4025 GetOrCreateMultiVersionResolver(GD); 4026 } else 4027 EmitGlobalFunctionDefinition(GD, GV); 4028 4029 // Defer the resolver emission until we can reason whether the TU 4030 // contains a default target version implementation. 4031 if (FD->isTargetVersionMultiVersion()) 4032 AddDeferredMultiVersionResolverToEmit(GD); 4033 } 4034 4035 void CodeGenModule::EmitGlobalDefinition(GlobalDecl GD, llvm::GlobalValue *GV) { 4036 const auto *D = cast<ValueDecl>(GD.getDecl()); 4037 4038 PrettyStackTraceDecl CrashInfo(const_cast<ValueDecl *>(D), D->getLocation(), 4039 Context.getSourceManager(), 4040 "Generating code for declaration"); 4041 4042 if (const auto *FD = dyn_cast<FunctionDecl>(D)) { 4043 // At -O0, don't generate IR for functions with available_externally 4044 // linkage. 4045 if (!shouldEmitFunction(GD)) 4046 return; 4047 4048 llvm::TimeTraceScope TimeScope("CodeGen Function", [&]() { 4049 std::string Name; 4050 llvm::raw_string_ostream OS(Name); 4051 FD->getNameForDiagnostic(OS, getContext().getPrintingPolicy(), 4052 /*Qualified=*/true); 4053 return Name; 4054 }); 4055 4056 if (const auto *Method = dyn_cast<CXXMethodDecl>(D)) { 4057 // Make sure to emit the definition(s) before we emit the thunks. 4058 // This is necessary for the generation of certain thunks. 4059 if (isa<CXXConstructorDecl>(Method) || isa<CXXDestructorDecl>(Method)) 4060 ABI->emitCXXStructor(GD); 4061 else if (FD->isMultiVersion()) 4062 EmitMultiVersionFunctionDefinition(GD, GV); 4063 else 4064 EmitGlobalFunctionDefinition(GD, GV); 4065 4066 if (Method->isVirtual()) 4067 getVTables().EmitThunks(GD); 4068 4069 return; 4070 } 4071 4072 if (FD->isMultiVersion()) 4073 return EmitMultiVersionFunctionDefinition(GD, GV); 4074 return EmitGlobalFunctionDefinition(GD, GV); 4075 } 4076 4077 if (const auto *VD = dyn_cast<VarDecl>(D)) 4078 return EmitGlobalVarDefinition(VD, !VD->hasDefinition()); 4079 4080 llvm_unreachable("Invalid argument to EmitGlobalDefinition()"); 4081 } 4082 4083 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 4084 llvm::Function *NewFn); 4085 4086 static unsigned 4087 TargetMVPriority(const TargetInfo &TI, 4088 const CodeGenFunction::MultiVersionResolverOption &RO) { 4089 unsigned Priority = 0; 4090 unsigned NumFeatures = 0; 4091 for (StringRef Feat : RO.Conditions.Features) { 4092 Priority = std::max(Priority, TI.multiVersionSortPriority(Feat)); 4093 NumFeatures++; 4094 } 4095 4096 if (!RO.Conditions.Architecture.empty()) 4097 Priority = std::max( 4098 Priority, TI.multiVersionSortPriority(RO.Conditions.Architecture)); 4099 4100 Priority += TI.multiVersionFeatureCost() * NumFeatures; 4101 4102 return Priority; 4103 } 4104 4105 // Multiversion functions should be at most 'WeakODRLinkage' so that a different 4106 // TU can forward declare the function without causing problems. Particularly 4107 // in the cases of CPUDispatch, this causes issues. This also makes sure we 4108 // work with internal linkage functions, so that the same function name can be 4109 // used with internal linkage in multiple TUs. 4110 llvm::GlobalValue::LinkageTypes getMultiversionLinkage(CodeGenModule &CGM, 4111 GlobalDecl GD) { 4112 const FunctionDecl *FD = cast<FunctionDecl>(GD.getDecl()); 4113 if (FD->getFormalLinkage() == Linkage::Internal) 4114 return llvm::GlobalValue::InternalLinkage; 4115 return llvm::GlobalValue::WeakODRLinkage; 4116 } 4117 4118 static FunctionDecl *createDefaultTargetVersionFrom(const FunctionDecl *FD) { 4119 DeclContext *DeclCtx = FD->getASTContext().getTranslationUnitDecl(); 4120 TypeSourceInfo *TInfo = FD->getTypeSourceInfo(); 4121 StorageClass SC = FD->getStorageClass(); 4122 DeclarationName Name = FD->getNameInfo().getName(); 4123 4124 FunctionDecl *NewDecl = 4125 FunctionDecl::Create(FD->getASTContext(), DeclCtx, FD->getBeginLoc(), 4126 FD->getEndLoc(), Name, TInfo->getType(), TInfo, SC); 4127 4128 NewDecl->setIsMultiVersion(); 4129 NewDecl->addAttr(TargetVersionAttr::CreateImplicit( 4130 NewDecl->getASTContext(), "default", NewDecl->getSourceRange())); 4131 4132 return NewDecl; 4133 } 4134 4135 void CodeGenModule::emitMultiVersionFunctions() { 4136 std::vector<GlobalDecl> MVFuncsToEmit; 4137 MultiVersionFuncs.swap(MVFuncsToEmit); 4138 for (GlobalDecl GD : MVFuncsToEmit) { 4139 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4140 assert(FD && "Expected a FunctionDecl"); 4141 4142 auto createFunction = [&](const FunctionDecl *Decl, unsigned MVIdx = 0) { 4143 GlobalDecl CurGD{Decl->isDefined() ? Decl->getDefinition() : Decl, MVIdx}; 4144 StringRef MangledName = getMangledName(CurGD); 4145 llvm::Constant *Func = GetGlobalValue(MangledName); 4146 if (!Func) { 4147 if (Decl->isDefined()) { 4148 EmitGlobalFunctionDefinition(CurGD, nullptr); 4149 Func = GetGlobalValue(MangledName); 4150 } else { 4151 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(CurGD); 4152 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 4153 Func = GetAddrOfFunction(CurGD, Ty, /*ForVTable=*/false, 4154 /*DontDefer=*/false, ForDefinition); 4155 } 4156 assert(Func && "This should have just been created"); 4157 } 4158 return cast<llvm::Function>(Func); 4159 }; 4160 4161 bool HasDefaultDecl = !FD->isTargetVersionMultiVersion(); 4162 bool ShouldEmitResolver = 4163 !getContext().getTargetInfo().getTriple().isAArch64(); 4164 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options; 4165 4166 getContext().forEachMultiversionedFunctionVersion( 4167 FD, [&](const FunctionDecl *CurFD) { 4168 llvm::SmallVector<StringRef, 8> Feats; 4169 4170 if (const auto *TA = CurFD->getAttr<TargetAttr>()) { 4171 TA->getAddedFeatures(Feats); 4172 llvm::Function *Func = createFunction(CurFD); 4173 Options.emplace_back(Func, TA->getArchitecture(), Feats); 4174 } else if (const auto *TVA = CurFD->getAttr<TargetVersionAttr>()) { 4175 bool HasDefaultDef = TVA->isDefaultVersion() && 4176 CurFD->doesThisDeclarationHaveABody(); 4177 HasDefaultDecl |= TVA->isDefaultVersion(); 4178 ShouldEmitResolver |= (CurFD->isUsed() || HasDefaultDef); 4179 TVA->getFeatures(Feats); 4180 llvm::Function *Func = createFunction(CurFD); 4181 Options.emplace_back(Func, /*Architecture*/ "", Feats); 4182 } else if (const auto *TC = CurFD->getAttr<TargetClonesAttr>()) { 4183 ShouldEmitResolver |= CurFD->doesThisDeclarationHaveABody(); 4184 for (unsigned I = 0; I < TC->featuresStrs_size(); ++I) { 4185 if (!TC->isFirstOfVersion(I)) 4186 continue; 4187 4188 llvm::Function *Func = createFunction(CurFD, I); 4189 StringRef Architecture; 4190 Feats.clear(); 4191 if (getTarget().getTriple().isAArch64()) 4192 TC->getFeatures(Feats, I); 4193 else { 4194 StringRef Version = TC->getFeatureStr(I); 4195 if (Version.starts_with("arch=")) 4196 Architecture = Version.drop_front(sizeof("arch=") - 1); 4197 else if (Version != "default") 4198 Feats.push_back(Version); 4199 } 4200 Options.emplace_back(Func, Architecture, Feats); 4201 } 4202 } else 4203 llvm_unreachable("unexpected MultiVersionKind"); 4204 }); 4205 4206 if (!ShouldEmitResolver) 4207 continue; 4208 4209 if (!HasDefaultDecl) { 4210 FunctionDecl *NewFD = createDefaultTargetVersionFrom(FD); 4211 llvm::Function *Func = createFunction(NewFD); 4212 llvm::SmallVector<StringRef, 1> Feats; 4213 Options.emplace_back(Func, /*Architecture*/ "", Feats); 4214 } 4215 4216 llvm::Constant *ResolverConstant = GetOrCreateMultiVersionResolver(GD); 4217 if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(ResolverConstant)) { 4218 ResolverConstant = IFunc->getResolver(); 4219 if (FD->isTargetClonesMultiVersion() || 4220 FD->isTargetVersionMultiVersion()) { 4221 std::string MangledName = getMangledNameImpl( 4222 *this, GD, FD, /*OmitMultiVersionMangling=*/true); 4223 if (!GetGlobalValue(MangledName + ".ifunc")) { 4224 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4225 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI); 4226 // In prior versions of Clang, the mangling for ifuncs incorrectly 4227 // included an .ifunc suffix. This alias is generated for backward 4228 // compatibility. It is deprecated, and may be removed in the future. 4229 auto *Alias = llvm::GlobalAlias::create( 4230 DeclTy, 0, getMultiversionLinkage(*this, GD), 4231 MangledName + ".ifunc", IFunc, &getModule()); 4232 SetCommonAttributes(FD, Alias); 4233 } 4234 } 4235 } 4236 llvm::Function *ResolverFunc = cast<llvm::Function>(ResolverConstant); 4237 4238 ResolverFunc->setLinkage(getMultiversionLinkage(*this, GD)); 4239 4240 if (!ResolverFunc->hasLocalLinkage() && supportsCOMDAT()) 4241 ResolverFunc->setComdat( 4242 getModule().getOrInsertComdat(ResolverFunc->getName())); 4243 4244 const TargetInfo &TI = getTarget(); 4245 llvm::stable_sort( 4246 Options, [&TI](const CodeGenFunction::MultiVersionResolverOption &LHS, 4247 const CodeGenFunction::MultiVersionResolverOption &RHS) { 4248 return TargetMVPriority(TI, LHS) > TargetMVPriority(TI, RHS); 4249 }); 4250 CodeGenFunction CGF(*this); 4251 CGF.EmitMultiVersionResolver(ResolverFunc, Options); 4252 } 4253 4254 // Ensure that any additions to the deferred decls list caused by emitting a 4255 // variant are emitted. This can happen when the variant itself is inline and 4256 // calls a function without linkage. 4257 if (!MVFuncsToEmit.empty()) 4258 EmitDeferred(); 4259 4260 // Ensure that any additions to the multiversion funcs list from either the 4261 // deferred decls or the multiversion functions themselves are emitted. 4262 if (!MultiVersionFuncs.empty()) 4263 emitMultiVersionFunctions(); 4264 } 4265 4266 void CodeGenModule::emitCPUDispatchDefinition(GlobalDecl GD) { 4267 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4268 assert(FD && "Not a FunctionDecl?"); 4269 assert(FD->isCPUDispatchMultiVersion() && "Not a multiversion function?"); 4270 const auto *DD = FD->getAttr<CPUDispatchAttr>(); 4271 assert(DD && "Not a cpu_dispatch Function?"); 4272 4273 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4274 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI); 4275 4276 StringRef ResolverName = getMangledName(GD); 4277 UpdateMultiVersionNames(GD, FD, ResolverName); 4278 4279 llvm::Type *ResolverType; 4280 GlobalDecl ResolverGD; 4281 if (getTarget().supportsIFunc()) { 4282 ResolverType = llvm::FunctionType::get( 4283 llvm::PointerType::get(DeclTy, 4284 getTypes().getTargetAddressSpace(FD->getType())), 4285 false); 4286 } 4287 else { 4288 ResolverType = DeclTy; 4289 ResolverGD = GD; 4290 } 4291 4292 auto *ResolverFunc = cast<llvm::Function>(GetOrCreateLLVMFunction( 4293 ResolverName, ResolverType, ResolverGD, /*ForVTable=*/false)); 4294 ResolverFunc->setLinkage(getMultiversionLinkage(*this, GD)); 4295 if (supportsCOMDAT()) 4296 ResolverFunc->setComdat( 4297 getModule().getOrInsertComdat(ResolverFunc->getName())); 4298 4299 SmallVector<CodeGenFunction::MultiVersionResolverOption, 10> Options; 4300 const TargetInfo &Target = getTarget(); 4301 unsigned Index = 0; 4302 for (const IdentifierInfo *II : DD->cpus()) { 4303 // Get the name of the target function so we can look it up/create it. 4304 std::string MangledName = getMangledNameImpl(*this, GD, FD, true) + 4305 getCPUSpecificMangling(*this, II->getName()); 4306 4307 llvm::Constant *Func = GetGlobalValue(MangledName); 4308 4309 if (!Func) { 4310 GlobalDecl ExistingDecl = Manglings.lookup(MangledName); 4311 if (ExistingDecl.getDecl() && 4312 ExistingDecl.getDecl()->getAsFunction()->isDefined()) { 4313 EmitGlobalFunctionDefinition(ExistingDecl, nullptr); 4314 Func = GetGlobalValue(MangledName); 4315 } else { 4316 if (!ExistingDecl.getDecl()) 4317 ExistingDecl = GD.getWithMultiVersionIndex(Index); 4318 4319 Func = GetOrCreateLLVMFunction( 4320 MangledName, DeclTy, ExistingDecl, 4321 /*ForVTable=*/false, /*DontDefer=*/true, 4322 /*IsThunk=*/false, llvm::AttributeList(), ForDefinition); 4323 } 4324 } 4325 4326 llvm::SmallVector<StringRef, 32> Features; 4327 Target.getCPUSpecificCPUDispatchFeatures(II->getName(), Features); 4328 llvm::transform(Features, Features.begin(), 4329 [](StringRef Str) { return Str.substr(1); }); 4330 llvm::erase_if(Features, [&Target](StringRef Feat) { 4331 return !Target.validateCpuSupports(Feat); 4332 }); 4333 Options.emplace_back(cast<llvm::Function>(Func), StringRef{}, Features); 4334 ++Index; 4335 } 4336 4337 llvm::stable_sort( 4338 Options, [](const CodeGenFunction::MultiVersionResolverOption &LHS, 4339 const CodeGenFunction::MultiVersionResolverOption &RHS) { 4340 return llvm::X86::getCpuSupportsMask(LHS.Conditions.Features) > 4341 llvm::X86::getCpuSupportsMask(RHS.Conditions.Features); 4342 }); 4343 4344 // If the list contains multiple 'default' versions, such as when it contains 4345 // 'pentium' and 'generic', don't emit the call to the generic one (since we 4346 // always run on at least a 'pentium'). We do this by deleting the 'least 4347 // advanced' (read, lowest mangling letter). 4348 while (Options.size() > 1 && 4349 llvm::all_of(llvm::X86::getCpuSupportsMask( 4350 (Options.end() - 2)->Conditions.Features), 4351 [](auto X) { return X == 0; })) { 4352 StringRef LHSName = (Options.end() - 2)->Function->getName(); 4353 StringRef RHSName = (Options.end() - 1)->Function->getName(); 4354 if (LHSName.compare(RHSName) < 0) 4355 Options.erase(Options.end() - 2); 4356 else 4357 Options.erase(Options.end() - 1); 4358 } 4359 4360 CodeGenFunction CGF(*this); 4361 CGF.EmitMultiVersionResolver(ResolverFunc, Options); 4362 4363 if (getTarget().supportsIFunc()) { 4364 llvm::GlobalValue::LinkageTypes Linkage = getMultiversionLinkage(*this, GD); 4365 auto *IFunc = cast<llvm::GlobalValue>(GetOrCreateMultiVersionResolver(GD)); 4366 4367 // Fix up function declarations that were created for cpu_specific before 4368 // cpu_dispatch was known 4369 if (!isa<llvm::GlobalIFunc>(IFunc)) { 4370 assert(cast<llvm::Function>(IFunc)->isDeclaration()); 4371 auto *GI = llvm::GlobalIFunc::create(DeclTy, 0, Linkage, "", ResolverFunc, 4372 &getModule()); 4373 GI->takeName(IFunc); 4374 IFunc->replaceAllUsesWith(GI); 4375 IFunc->eraseFromParent(); 4376 IFunc = GI; 4377 } 4378 4379 std::string AliasName = getMangledNameImpl( 4380 *this, GD, FD, /*OmitMultiVersionMangling=*/true); 4381 llvm::Constant *AliasFunc = GetGlobalValue(AliasName); 4382 if (!AliasFunc) { 4383 auto *GA = llvm::GlobalAlias::create(DeclTy, 0, Linkage, AliasName, IFunc, 4384 &getModule()); 4385 SetCommonAttributes(GD, GA); 4386 } 4387 } 4388 } 4389 4390 /// Adds a declaration to the list of multi version functions if not present. 4391 void CodeGenModule::AddDeferredMultiVersionResolverToEmit(GlobalDecl GD) { 4392 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4393 assert(FD && "Not a FunctionDecl?"); 4394 4395 if (FD->isTargetVersionMultiVersion() || FD->isTargetClonesMultiVersion()) { 4396 std::string MangledName = 4397 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true); 4398 if (!DeferredResolversToEmit.insert(MangledName).second) 4399 return; 4400 } 4401 MultiVersionFuncs.push_back(GD); 4402 } 4403 4404 /// If a dispatcher for the specified mangled name is not in the module, create 4405 /// and return an llvm Function with the specified type. 4406 llvm::Constant *CodeGenModule::GetOrCreateMultiVersionResolver(GlobalDecl GD) { 4407 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4408 assert(FD && "Not a FunctionDecl?"); 4409 4410 std::string MangledName = 4411 getMangledNameImpl(*this, GD, FD, /*OmitMultiVersionMangling=*/true); 4412 4413 // Holds the name of the resolver, in ifunc mode this is the ifunc (which has 4414 // a separate resolver). 4415 std::string ResolverName = MangledName; 4416 if (getTarget().supportsIFunc()) { 4417 switch (FD->getMultiVersionKind()) { 4418 case MultiVersionKind::None: 4419 llvm_unreachable("unexpected MultiVersionKind::None for resolver"); 4420 case MultiVersionKind::Target: 4421 case MultiVersionKind::CPUSpecific: 4422 case MultiVersionKind::CPUDispatch: 4423 ResolverName += ".ifunc"; 4424 break; 4425 case MultiVersionKind::TargetClones: 4426 case MultiVersionKind::TargetVersion: 4427 break; 4428 } 4429 } else if (FD->isTargetMultiVersion()) { 4430 ResolverName += ".resolver"; 4431 } 4432 4433 // If the resolver has already been created, just return it. 4434 if (llvm::GlobalValue *ResolverGV = GetGlobalValue(ResolverName)) 4435 return ResolverGV; 4436 4437 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 4438 llvm::FunctionType *DeclTy = getTypes().GetFunctionType(FI); 4439 4440 // The resolver needs to be created. For target and target_clones, defer 4441 // creation until the end of the TU. 4442 if (FD->isTargetMultiVersion() || FD->isTargetClonesMultiVersion()) 4443 AddDeferredMultiVersionResolverToEmit(GD); 4444 4445 // For cpu_specific, don't create an ifunc yet because we don't know if the 4446 // cpu_dispatch will be emitted in this translation unit. 4447 if (getTarget().supportsIFunc() && !FD->isCPUSpecificMultiVersion()) { 4448 llvm::Type *ResolverType = llvm::FunctionType::get( 4449 llvm::PointerType::get(DeclTy, 4450 getTypes().getTargetAddressSpace(FD->getType())), 4451 false); 4452 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 4453 MangledName + ".resolver", ResolverType, GlobalDecl{}, 4454 /*ForVTable=*/false); 4455 llvm::GlobalIFunc *GIF = 4456 llvm::GlobalIFunc::create(DeclTy, 0, getMultiversionLinkage(*this, GD), 4457 "", Resolver, &getModule()); 4458 GIF->setName(ResolverName); 4459 SetCommonAttributes(FD, GIF); 4460 4461 return GIF; 4462 } 4463 4464 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 4465 ResolverName, DeclTy, GlobalDecl{}, /*ForVTable=*/false); 4466 assert(isa<llvm::GlobalValue>(Resolver) && 4467 "Resolver should be created for the first time"); 4468 SetCommonAttributes(FD, cast<llvm::GlobalValue>(Resolver)); 4469 return Resolver; 4470 } 4471 4472 /// GetOrCreateLLVMFunction - If the specified mangled name is not in the 4473 /// module, create and return an llvm Function with the specified type. If there 4474 /// is something in the module with the specified name, return it potentially 4475 /// bitcasted to the right type. 4476 /// 4477 /// If D is non-null, it specifies a decl that correspond to this. This is used 4478 /// to set the attributes on the function when it is first created. 4479 llvm::Constant *CodeGenModule::GetOrCreateLLVMFunction( 4480 StringRef MangledName, llvm::Type *Ty, GlobalDecl GD, bool ForVTable, 4481 bool DontDefer, bool IsThunk, llvm::AttributeList ExtraAttrs, 4482 ForDefinition_t IsForDefinition) { 4483 const Decl *D = GD.getDecl(); 4484 4485 // Any attempts to use a MultiVersion function should result in retrieving 4486 // the iFunc instead. Name Mangling will handle the rest of the changes. 4487 if (const FunctionDecl *FD = cast_or_null<FunctionDecl>(D)) { 4488 // For the device mark the function as one that should be emitted. 4489 if (getLangOpts().OpenMPIsTargetDevice && OpenMPRuntime && 4490 !OpenMPRuntime->markAsGlobalTarget(GD) && FD->isDefined() && 4491 !DontDefer && !IsForDefinition) { 4492 if (const FunctionDecl *FDDef = FD->getDefinition()) { 4493 GlobalDecl GDDef; 4494 if (const auto *CD = dyn_cast<CXXConstructorDecl>(FDDef)) 4495 GDDef = GlobalDecl(CD, GD.getCtorType()); 4496 else if (const auto *DD = dyn_cast<CXXDestructorDecl>(FDDef)) 4497 GDDef = GlobalDecl(DD, GD.getDtorType()); 4498 else 4499 GDDef = GlobalDecl(FDDef); 4500 EmitGlobal(GDDef); 4501 } 4502 } 4503 4504 if (FD->isMultiVersion()) { 4505 UpdateMultiVersionNames(GD, FD, MangledName); 4506 if (FD->getASTContext().getTargetInfo().getTriple().isAArch64() && 4507 !FD->isUsed()) 4508 AddDeferredMultiVersionResolverToEmit(GD); 4509 else if (!IsForDefinition) 4510 return GetOrCreateMultiVersionResolver(GD); 4511 } 4512 } 4513 4514 // Lookup the entry, lazily creating it if necessary. 4515 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 4516 if (Entry) { 4517 if (WeakRefReferences.erase(Entry)) { 4518 const FunctionDecl *FD = cast_or_null<FunctionDecl>(D); 4519 if (FD && !FD->hasAttr<WeakAttr>()) 4520 Entry->setLinkage(llvm::Function::ExternalLinkage); 4521 } 4522 4523 // Handle dropped DLL attributes. 4524 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() && 4525 !shouldMapVisibilityToDLLExport(cast_or_null<NamedDecl>(D))) { 4526 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass); 4527 setDSOLocal(Entry); 4528 } 4529 4530 // If there are two attempts to define the same mangled name, issue an 4531 // error. 4532 if (IsForDefinition && !Entry->isDeclaration()) { 4533 GlobalDecl OtherGD; 4534 // Check that GD is not yet in DiagnosedConflictingDefinitions is required 4535 // to make sure that we issue an error only once. 4536 if (lookupRepresentativeDecl(MangledName, OtherGD) && 4537 (GD.getCanonicalDecl().getDecl() != 4538 OtherGD.getCanonicalDecl().getDecl()) && 4539 DiagnosedConflictingDefinitions.insert(GD).second) { 4540 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name) 4541 << MangledName; 4542 getDiags().Report(OtherGD.getDecl()->getLocation(), 4543 diag::note_previous_definition); 4544 } 4545 } 4546 4547 if ((isa<llvm::Function>(Entry) || isa<llvm::GlobalAlias>(Entry)) && 4548 (Entry->getValueType() == Ty)) { 4549 return Entry; 4550 } 4551 4552 // Make sure the result is of the correct type. 4553 // (If function is requested for a definition, we always need to create a new 4554 // function, not just return a bitcast.) 4555 if (!IsForDefinition) 4556 return Entry; 4557 } 4558 4559 // This function doesn't have a complete type (for example, the return 4560 // type is an incomplete struct). Use a fake type instead, and make 4561 // sure not to try to set attributes. 4562 bool IsIncompleteFunction = false; 4563 4564 llvm::FunctionType *FTy; 4565 if (isa<llvm::FunctionType>(Ty)) { 4566 FTy = cast<llvm::FunctionType>(Ty); 4567 } else { 4568 FTy = llvm::FunctionType::get(VoidTy, false); 4569 IsIncompleteFunction = true; 4570 } 4571 4572 llvm::Function *F = 4573 llvm::Function::Create(FTy, llvm::Function::ExternalLinkage, 4574 Entry ? StringRef() : MangledName, &getModule()); 4575 4576 // Store the declaration associated with this function so it is potentially 4577 // updated by further declarations or definitions and emitted at the end. 4578 if (D && D->hasAttr<AnnotateAttr>()) 4579 DeferredAnnotations[MangledName] = cast<ValueDecl>(D); 4580 4581 // If we already created a function with the same mangled name (but different 4582 // type) before, take its name and add it to the list of functions to be 4583 // replaced with F at the end of CodeGen. 4584 // 4585 // This happens if there is a prototype for a function (e.g. "int f()") and 4586 // then a definition of a different type (e.g. "int f(int x)"). 4587 if (Entry) { 4588 F->takeName(Entry); 4589 4590 // This might be an implementation of a function without a prototype, in 4591 // which case, try to do special replacement of calls which match the new 4592 // prototype. The really key thing here is that we also potentially drop 4593 // arguments from the call site so as to make a direct call, which makes the 4594 // inliner happier and suppresses a number of optimizer warnings (!) about 4595 // dropping arguments. 4596 if (!Entry->use_empty()) { 4597 ReplaceUsesOfNonProtoTypeWithRealFunction(Entry, F); 4598 Entry->removeDeadConstantUsers(); 4599 } 4600 4601 addGlobalValReplacement(Entry, F); 4602 } 4603 4604 assert(F->getName() == MangledName && "name was uniqued!"); 4605 if (D) 4606 SetFunctionAttributes(GD, F, IsIncompleteFunction, IsThunk); 4607 if (ExtraAttrs.hasFnAttrs()) { 4608 llvm::AttrBuilder B(F->getContext(), ExtraAttrs.getFnAttrs()); 4609 F->addFnAttrs(B); 4610 } 4611 4612 if (!DontDefer) { 4613 // All MSVC dtors other than the base dtor are linkonce_odr and delegate to 4614 // each other bottoming out with the base dtor. Therefore we emit non-base 4615 // dtors on usage, even if there is no dtor definition in the TU. 4616 if (isa_and_nonnull<CXXDestructorDecl>(D) && 4617 getCXXABI().useThunkForDtorVariant(cast<CXXDestructorDecl>(D), 4618 GD.getDtorType())) 4619 addDeferredDeclToEmit(GD); 4620 4621 // This is the first use or definition of a mangled name. If there is a 4622 // deferred decl with this name, remember that we need to emit it at the end 4623 // of the file. 4624 auto DDI = DeferredDecls.find(MangledName); 4625 if (DDI != DeferredDecls.end()) { 4626 // Move the potentially referenced deferred decl to the 4627 // DeferredDeclsToEmit list, and remove it from DeferredDecls (since we 4628 // don't need it anymore). 4629 addDeferredDeclToEmit(DDI->second); 4630 DeferredDecls.erase(DDI); 4631 4632 // Otherwise, there are cases we have to worry about where we're 4633 // using a declaration for which we must emit a definition but where 4634 // we might not find a top-level definition: 4635 // - member functions defined inline in their classes 4636 // - friend functions defined inline in some class 4637 // - special member functions with implicit definitions 4638 // If we ever change our AST traversal to walk into class methods, 4639 // this will be unnecessary. 4640 // 4641 // We also don't emit a definition for a function if it's going to be an 4642 // entry in a vtable, unless it's already marked as used. 4643 } else if (getLangOpts().CPlusPlus && D) { 4644 // Look for a declaration that's lexically in a record. 4645 for (const auto *FD = cast<FunctionDecl>(D)->getMostRecentDecl(); FD; 4646 FD = FD->getPreviousDecl()) { 4647 if (isa<CXXRecordDecl>(FD->getLexicalDeclContext())) { 4648 if (FD->doesThisDeclarationHaveABody()) { 4649 addDeferredDeclToEmit(GD.getWithDecl(FD)); 4650 break; 4651 } 4652 } 4653 } 4654 } 4655 } 4656 4657 // Make sure the result is of the requested type. 4658 if (!IsIncompleteFunction) { 4659 assert(F->getFunctionType() == Ty); 4660 return F; 4661 } 4662 4663 return F; 4664 } 4665 4666 /// GetAddrOfFunction - Return the address of the given function. If Ty is 4667 /// non-null, then this function will use the specified type if it has to 4668 /// create it (this occurs when we see a definition of the function). 4669 llvm::Constant * 4670 CodeGenModule::GetAddrOfFunction(GlobalDecl GD, llvm::Type *Ty, bool ForVTable, 4671 bool DontDefer, 4672 ForDefinition_t IsForDefinition) { 4673 // If there was no specific requested type, just convert it now. 4674 if (!Ty) { 4675 const auto *FD = cast<FunctionDecl>(GD.getDecl()); 4676 Ty = getTypes().ConvertType(FD->getType()); 4677 } 4678 4679 // Devirtualized destructor calls may come through here instead of via 4680 // getAddrOfCXXStructor. Make sure we use the MS ABI base destructor instead 4681 // of the complete destructor when necessary. 4682 if (const auto *DD = dyn_cast<CXXDestructorDecl>(GD.getDecl())) { 4683 if (getTarget().getCXXABI().isMicrosoft() && 4684 GD.getDtorType() == Dtor_Complete && 4685 DD->getParent()->getNumVBases() == 0) 4686 GD = GlobalDecl(DD, Dtor_Base); 4687 } 4688 4689 StringRef MangledName = getMangledName(GD); 4690 auto *F = GetOrCreateLLVMFunction(MangledName, Ty, GD, ForVTable, DontDefer, 4691 /*IsThunk=*/false, llvm::AttributeList(), 4692 IsForDefinition); 4693 // Returns kernel handle for HIP kernel stub function. 4694 if (LangOpts.CUDA && !LangOpts.CUDAIsDevice && 4695 cast<FunctionDecl>(GD.getDecl())->hasAttr<CUDAGlobalAttr>()) { 4696 auto *Handle = getCUDARuntime().getKernelHandle( 4697 cast<llvm::Function>(F->stripPointerCasts()), GD); 4698 if (IsForDefinition) 4699 return F; 4700 return Handle; 4701 } 4702 return F; 4703 } 4704 4705 llvm::Constant *CodeGenModule::GetFunctionStart(const ValueDecl *Decl) { 4706 llvm::GlobalValue *F = 4707 cast<llvm::GlobalValue>(GetAddrOfFunction(Decl)->stripPointerCasts()); 4708 4709 return llvm::NoCFIValue::get(F); 4710 } 4711 4712 static const FunctionDecl * 4713 GetRuntimeFunctionDecl(ASTContext &C, StringRef Name) { 4714 TranslationUnitDecl *TUDecl = C.getTranslationUnitDecl(); 4715 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); 4716 4717 IdentifierInfo &CII = C.Idents.get(Name); 4718 for (const auto *Result : DC->lookup(&CII)) 4719 if (const auto *FD = dyn_cast<FunctionDecl>(Result)) 4720 return FD; 4721 4722 if (!C.getLangOpts().CPlusPlus) 4723 return nullptr; 4724 4725 // Demangle the premangled name from getTerminateFn() 4726 IdentifierInfo &CXXII = 4727 (Name == "_ZSt9terminatev" || Name == "?terminate@@YAXXZ") 4728 ? C.Idents.get("terminate") 4729 : C.Idents.get(Name); 4730 4731 for (const auto &N : {"__cxxabiv1", "std"}) { 4732 IdentifierInfo &NS = C.Idents.get(N); 4733 for (const auto *Result : DC->lookup(&NS)) { 4734 const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(Result); 4735 if (auto *LSD = dyn_cast<LinkageSpecDecl>(Result)) 4736 for (const auto *Result : LSD->lookup(&NS)) 4737 if ((ND = dyn_cast<NamespaceDecl>(Result))) 4738 break; 4739 4740 if (ND) 4741 for (const auto *Result : ND->lookup(&CXXII)) 4742 if (const auto *FD = dyn_cast<FunctionDecl>(Result)) 4743 return FD; 4744 } 4745 } 4746 4747 return nullptr; 4748 } 4749 4750 /// CreateRuntimeFunction - Create a new runtime function with the specified 4751 /// type and name. 4752 llvm::FunctionCallee 4753 CodeGenModule::CreateRuntimeFunction(llvm::FunctionType *FTy, StringRef Name, 4754 llvm::AttributeList ExtraAttrs, bool Local, 4755 bool AssumeConvergent) { 4756 if (AssumeConvergent) { 4757 ExtraAttrs = 4758 ExtraAttrs.addFnAttribute(VMContext, llvm::Attribute::Convergent); 4759 } 4760 4761 llvm::Constant *C = 4762 GetOrCreateLLVMFunction(Name, FTy, GlobalDecl(), /*ForVTable=*/false, 4763 /*DontDefer=*/false, /*IsThunk=*/false, 4764 ExtraAttrs); 4765 4766 if (auto *F = dyn_cast<llvm::Function>(C)) { 4767 if (F->empty()) { 4768 F->setCallingConv(getRuntimeCC()); 4769 4770 // In Windows Itanium environments, try to mark runtime functions 4771 // dllimport. For Mingw and MSVC, don't. We don't really know if the user 4772 // will link their standard library statically or dynamically. Marking 4773 // functions imported when they are not imported can cause linker errors 4774 // and warnings. 4775 if (!Local && getTriple().isWindowsItaniumEnvironment() && 4776 !getCodeGenOpts().LTOVisibilityPublicStd) { 4777 const FunctionDecl *FD = GetRuntimeFunctionDecl(Context, Name); 4778 if (!FD || FD->hasAttr<DLLImportAttr>()) { 4779 F->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass); 4780 F->setLinkage(llvm::GlobalValue::ExternalLinkage); 4781 } 4782 } 4783 setDSOLocal(F); 4784 } 4785 } 4786 4787 return {FTy, C}; 4788 } 4789 4790 /// GetOrCreateLLVMGlobal - If the specified mangled name is not in the module, 4791 /// create and return an llvm GlobalVariable with the specified type and address 4792 /// space. If there is something in the module with the specified name, return 4793 /// it potentially bitcasted to the right type. 4794 /// 4795 /// If D is non-null, it specifies a decl that correspond to this. This is used 4796 /// to set the attributes on the global when it is first created. 4797 /// 4798 /// If IsForDefinition is true, it is guaranteed that an actual global with 4799 /// type Ty will be returned, not conversion of a variable with the same 4800 /// mangled name but some other type. 4801 llvm::Constant * 4802 CodeGenModule::GetOrCreateLLVMGlobal(StringRef MangledName, llvm::Type *Ty, 4803 LangAS AddrSpace, const VarDecl *D, 4804 ForDefinition_t IsForDefinition) { 4805 // Lookup the entry, lazily creating it if necessary. 4806 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 4807 unsigned TargetAS = getContext().getTargetAddressSpace(AddrSpace); 4808 if (Entry) { 4809 if (WeakRefReferences.erase(Entry)) { 4810 if (D && !D->hasAttr<WeakAttr>()) 4811 Entry->setLinkage(llvm::Function::ExternalLinkage); 4812 } 4813 4814 // Handle dropped DLL attributes. 4815 if (D && !D->hasAttr<DLLImportAttr>() && !D->hasAttr<DLLExportAttr>() && 4816 !shouldMapVisibilityToDLLExport(D)) 4817 Entry->setDLLStorageClass(llvm::GlobalValue::DefaultStorageClass); 4818 4819 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd && D) 4820 getOpenMPRuntime().registerTargetGlobalVariable(D, Entry); 4821 4822 if (Entry->getValueType() == Ty && Entry->getAddressSpace() == TargetAS) 4823 return Entry; 4824 4825 // If there are two attempts to define the same mangled name, issue an 4826 // error. 4827 if (IsForDefinition && !Entry->isDeclaration()) { 4828 GlobalDecl OtherGD; 4829 const VarDecl *OtherD; 4830 4831 // Check that D is not yet in DiagnosedConflictingDefinitions is required 4832 // to make sure that we issue an error only once. 4833 if (D && lookupRepresentativeDecl(MangledName, OtherGD) && 4834 (D->getCanonicalDecl() != OtherGD.getCanonicalDecl().getDecl()) && 4835 (OtherD = dyn_cast<VarDecl>(OtherGD.getDecl())) && 4836 OtherD->hasInit() && 4837 DiagnosedConflictingDefinitions.insert(D).second) { 4838 getDiags().Report(D->getLocation(), diag::err_duplicate_mangled_name) 4839 << MangledName; 4840 getDiags().Report(OtherGD.getDecl()->getLocation(), 4841 diag::note_previous_definition); 4842 } 4843 } 4844 4845 // Make sure the result is of the correct type. 4846 if (Entry->getType()->getAddressSpace() != TargetAS) 4847 return llvm::ConstantExpr::getAddrSpaceCast( 4848 Entry, llvm::PointerType::get(Ty->getContext(), TargetAS)); 4849 4850 // (If global is requested for a definition, we always need to create a new 4851 // global, not just return a bitcast.) 4852 if (!IsForDefinition) 4853 return Entry; 4854 } 4855 4856 auto DAddrSpace = GetGlobalVarAddressSpace(D); 4857 4858 auto *GV = new llvm::GlobalVariable( 4859 getModule(), Ty, false, llvm::GlobalValue::ExternalLinkage, nullptr, 4860 MangledName, nullptr, llvm::GlobalVariable::NotThreadLocal, 4861 getContext().getTargetAddressSpace(DAddrSpace)); 4862 4863 // If we already created a global with the same mangled name (but different 4864 // type) before, take its name and remove it from its parent. 4865 if (Entry) { 4866 GV->takeName(Entry); 4867 4868 if (!Entry->use_empty()) { 4869 Entry->replaceAllUsesWith(GV); 4870 } 4871 4872 Entry->eraseFromParent(); 4873 } 4874 4875 // This is the first use or definition of a mangled name. If there is a 4876 // deferred decl with this name, remember that we need to emit it at the end 4877 // of the file. 4878 auto DDI = DeferredDecls.find(MangledName); 4879 if (DDI != DeferredDecls.end()) { 4880 // Move the potentially referenced deferred decl to the DeferredDeclsToEmit 4881 // list, and remove it from DeferredDecls (since we don't need it anymore). 4882 addDeferredDeclToEmit(DDI->second); 4883 DeferredDecls.erase(DDI); 4884 } 4885 4886 // Handle things which are present even on external declarations. 4887 if (D) { 4888 if (LangOpts.OpenMP && !LangOpts.OpenMPSimd) 4889 getOpenMPRuntime().registerTargetGlobalVariable(D, GV); 4890 4891 // FIXME: This code is overly simple and should be merged with other global 4892 // handling. 4893 GV->setConstant(D->getType().isConstantStorage(getContext(), false, false)); 4894 4895 GV->setAlignment(getContext().getDeclAlign(D).getAsAlign()); 4896 4897 setLinkageForGV(GV, D); 4898 4899 if (D->getTLSKind()) { 4900 if (D->getTLSKind() == VarDecl::TLS_Dynamic) 4901 CXXThreadLocals.push_back(D); 4902 setTLSMode(GV, *D); 4903 } 4904 4905 setGVProperties(GV, D); 4906 4907 // If required by the ABI, treat declarations of static data members with 4908 // inline initializers as definitions. 4909 if (getContext().isMSStaticDataMemberInlineDefinition(D)) { 4910 EmitGlobalVarDefinition(D); 4911 } 4912 4913 // Emit section information for extern variables. 4914 if (D->hasExternalStorage()) { 4915 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) 4916 GV->setSection(SA->getName()); 4917 } 4918 4919 // Handle XCore specific ABI requirements. 4920 if (getTriple().getArch() == llvm::Triple::xcore && 4921 D->getLanguageLinkage() == CLanguageLinkage && 4922 D->getType().isConstant(Context) && 4923 isExternallyVisible(D->getLinkageAndVisibility().getLinkage())) 4924 GV->setSection(".cp.rodata"); 4925 4926 // Handle code model attribute 4927 if (const auto *CMA = D->getAttr<CodeModelAttr>()) 4928 GV->setCodeModel(CMA->getModel()); 4929 4930 // Check if we a have a const declaration with an initializer, we may be 4931 // able to emit it as available_externally to expose it's value to the 4932 // optimizer. 4933 if (Context.getLangOpts().CPlusPlus && GV->hasExternalLinkage() && 4934 D->getType().isConstQualified() && !GV->hasInitializer() && 4935 !D->hasDefinition() && D->hasInit() && !D->hasAttr<DLLImportAttr>()) { 4936 const auto *Record = 4937 Context.getBaseElementType(D->getType())->getAsCXXRecordDecl(); 4938 bool HasMutableFields = Record && Record->hasMutableFields(); 4939 if (!HasMutableFields) { 4940 const VarDecl *InitDecl; 4941 const Expr *InitExpr = D->getAnyInitializer(InitDecl); 4942 if (InitExpr) { 4943 ConstantEmitter emitter(*this); 4944 llvm::Constant *Init = emitter.tryEmitForInitializer(*InitDecl); 4945 if (Init) { 4946 auto *InitType = Init->getType(); 4947 if (GV->getValueType() != InitType) { 4948 // The type of the initializer does not match the definition. 4949 // This happens when an initializer has a different type from 4950 // the type of the global (because of padding at the end of a 4951 // structure for instance). 4952 GV->setName(StringRef()); 4953 // Make a new global with the correct type, this is now guaranteed 4954 // to work. 4955 auto *NewGV = cast<llvm::GlobalVariable>( 4956 GetAddrOfGlobalVar(D, InitType, IsForDefinition) 4957 ->stripPointerCasts()); 4958 4959 // Erase the old global, since it is no longer used. 4960 GV->eraseFromParent(); 4961 GV = NewGV; 4962 } else { 4963 GV->setInitializer(Init); 4964 GV->setConstant(true); 4965 GV->setLinkage(llvm::GlobalValue::AvailableExternallyLinkage); 4966 } 4967 emitter.finalize(GV); 4968 } 4969 } 4970 } 4971 } 4972 } 4973 4974 if (D && 4975 D->isThisDeclarationADefinition(Context) == VarDecl::DeclarationOnly) { 4976 getTargetCodeGenInfo().setTargetAttributes(D, GV, *this); 4977 // External HIP managed variables needed to be recorded for transformation 4978 // in both device and host compilations. 4979 if (getLangOpts().CUDA && D && D->hasAttr<HIPManagedAttr>() && 4980 D->hasExternalStorage()) 4981 getCUDARuntime().handleVarRegistration(D, *GV); 4982 } 4983 4984 if (D) 4985 SanitizerMD->reportGlobal(GV, *D); 4986 4987 LangAS ExpectedAS = 4988 D ? D->getType().getAddressSpace() 4989 : (LangOpts.OpenCL ? LangAS::opencl_global : LangAS::Default); 4990 assert(getContext().getTargetAddressSpace(ExpectedAS) == TargetAS); 4991 if (DAddrSpace != ExpectedAS) { 4992 return getTargetCodeGenInfo().performAddrSpaceCast( 4993 *this, GV, DAddrSpace, ExpectedAS, 4994 llvm::PointerType::get(getLLVMContext(), TargetAS)); 4995 } 4996 4997 return GV; 4998 } 4999 5000 llvm::Constant * 5001 CodeGenModule::GetAddrOfGlobal(GlobalDecl GD, ForDefinition_t IsForDefinition) { 5002 const Decl *D = GD.getDecl(); 5003 5004 if (isa<CXXConstructorDecl>(D) || isa<CXXDestructorDecl>(D)) 5005 return getAddrOfCXXStructor(GD, /*FnInfo=*/nullptr, /*FnType=*/nullptr, 5006 /*DontDefer=*/false, IsForDefinition); 5007 5008 if (isa<CXXMethodDecl>(D)) { 5009 auto FInfo = 5010 &getTypes().arrangeCXXMethodDeclaration(cast<CXXMethodDecl>(D)); 5011 auto Ty = getTypes().GetFunctionType(*FInfo); 5012 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false, 5013 IsForDefinition); 5014 } 5015 5016 if (isa<FunctionDecl>(D)) { 5017 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 5018 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 5019 return GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, /*DontDefer=*/false, 5020 IsForDefinition); 5021 } 5022 5023 return GetAddrOfGlobalVar(cast<VarDecl>(D), /*Ty=*/nullptr, IsForDefinition); 5024 } 5025 5026 llvm::GlobalVariable *CodeGenModule::CreateOrReplaceCXXRuntimeVariable( 5027 StringRef Name, llvm::Type *Ty, llvm::GlobalValue::LinkageTypes Linkage, 5028 llvm::Align Alignment) { 5029 llvm::GlobalVariable *GV = getModule().getNamedGlobal(Name); 5030 llvm::GlobalVariable *OldGV = nullptr; 5031 5032 if (GV) { 5033 // Check if the variable has the right type. 5034 if (GV->getValueType() == Ty) 5035 return GV; 5036 5037 // Because C++ name mangling, the only way we can end up with an already 5038 // existing global with the same name is if it has been declared extern "C". 5039 assert(GV->isDeclaration() && "Declaration has wrong type!"); 5040 OldGV = GV; 5041 } 5042 5043 // Create a new variable. 5044 GV = new llvm::GlobalVariable(getModule(), Ty, /*isConstant=*/true, 5045 Linkage, nullptr, Name); 5046 5047 if (OldGV) { 5048 // Replace occurrences of the old variable if needed. 5049 GV->takeName(OldGV); 5050 5051 if (!OldGV->use_empty()) { 5052 OldGV->replaceAllUsesWith(GV); 5053 } 5054 5055 OldGV->eraseFromParent(); 5056 } 5057 5058 if (supportsCOMDAT() && GV->isWeakForLinker() && 5059 !GV->hasAvailableExternallyLinkage()) 5060 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 5061 5062 GV->setAlignment(Alignment); 5063 5064 return GV; 5065 } 5066 5067 /// GetAddrOfGlobalVar - Return the llvm::Constant for the address of the 5068 /// given global variable. If Ty is non-null and if the global doesn't exist, 5069 /// then it will be created with the specified type instead of whatever the 5070 /// normal requested type would be. If IsForDefinition is true, it is guaranteed 5071 /// that an actual global with type Ty will be returned, not conversion of a 5072 /// variable with the same mangled name but some other type. 5073 llvm::Constant *CodeGenModule::GetAddrOfGlobalVar(const VarDecl *D, 5074 llvm::Type *Ty, 5075 ForDefinition_t IsForDefinition) { 5076 assert(D->hasGlobalStorage() && "Not a global variable"); 5077 QualType ASTTy = D->getType(); 5078 if (!Ty) 5079 Ty = getTypes().ConvertTypeForMem(ASTTy); 5080 5081 StringRef MangledName = getMangledName(D); 5082 return GetOrCreateLLVMGlobal(MangledName, Ty, ASTTy.getAddressSpace(), D, 5083 IsForDefinition); 5084 } 5085 5086 /// CreateRuntimeVariable - Create a new runtime global variable with the 5087 /// specified type and name. 5088 llvm::Constant * 5089 CodeGenModule::CreateRuntimeVariable(llvm::Type *Ty, 5090 StringRef Name) { 5091 LangAS AddrSpace = getContext().getLangOpts().OpenCL ? LangAS::opencl_global 5092 : LangAS::Default; 5093 auto *Ret = GetOrCreateLLVMGlobal(Name, Ty, AddrSpace, nullptr); 5094 setDSOLocal(cast<llvm::GlobalValue>(Ret->stripPointerCasts())); 5095 return Ret; 5096 } 5097 5098 void CodeGenModule::EmitTentativeDefinition(const VarDecl *D) { 5099 assert(!D->getInit() && "Cannot emit definite definitions here!"); 5100 5101 StringRef MangledName = getMangledName(D); 5102 llvm::GlobalValue *GV = GetGlobalValue(MangledName); 5103 5104 // We already have a definition, not declaration, with the same mangled name. 5105 // Emitting of declaration is not required (and actually overwrites emitted 5106 // definition). 5107 if (GV && !GV->isDeclaration()) 5108 return; 5109 5110 // If we have not seen a reference to this variable yet, place it into the 5111 // deferred declarations table to be emitted if needed later. 5112 if (!MustBeEmitted(D) && !GV) { 5113 DeferredDecls[MangledName] = D; 5114 return; 5115 } 5116 5117 // The tentative definition is the only definition. 5118 EmitGlobalVarDefinition(D); 5119 } 5120 5121 void CodeGenModule::EmitExternalDeclaration(const VarDecl *D) { 5122 EmitExternalVarDeclaration(D); 5123 } 5124 5125 CharUnits CodeGenModule::GetTargetTypeStoreSize(llvm::Type *Ty) const { 5126 return Context.toCharUnitsFromBits( 5127 getDataLayout().getTypeStoreSizeInBits(Ty)); 5128 } 5129 5130 LangAS CodeGenModule::GetGlobalVarAddressSpace(const VarDecl *D) { 5131 if (LangOpts.OpenCL) { 5132 LangAS AS = D ? D->getType().getAddressSpace() : LangAS::opencl_global; 5133 assert(AS == LangAS::opencl_global || 5134 AS == LangAS::opencl_global_device || 5135 AS == LangAS::opencl_global_host || 5136 AS == LangAS::opencl_constant || 5137 AS == LangAS::opencl_local || 5138 AS >= LangAS::FirstTargetAddressSpace); 5139 return AS; 5140 } 5141 5142 if (LangOpts.SYCLIsDevice && 5143 (!D || D->getType().getAddressSpace() == LangAS::Default)) 5144 return LangAS::sycl_global; 5145 5146 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) { 5147 if (D) { 5148 if (D->hasAttr<CUDAConstantAttr>()) 5149 return LangAS::cuda_constant; 5150 if (D->hasAttr<CUDASharedAttr>()) 5151 return LangAS::cuda_shared; 5152 if (D->hasAttr<CUDADeviceAttr>()) 5153 return LangAS::cuda_device; 5154 if (D->getType().isConstQualified()) 5155 return LangAS::cuda_constant; 5156 } 5157 return LangAS::cuda_device; 5158 } 5159 5160 if (LangOpts.OpenMP) { 5161 LangAS AS; 5162 if (OpenMPRuntime->hasAllocateAttributeForGlobalVar(D, AS)) 5163 return AS; 5164 } 5165 return getTargetCodeGenInfo().getGlobalVarAddressSpace(*this, D); 5166 } 5167 5168 LangAS CodeGenModule::GetGlobalConstantAddressSpace() const { 5169 // OpenCL v1.2 s6.5.3: a string literal is in the constant address space. 5170 if (LangOpts.OpenCL) 5171 return LangAS::opencl_constant; 5172 if (LangOpts.SYCLIsDevice) 5173 return LangAS::sycl_global; 5174 if (LangOpts.HIP && LangOpts.CUDAIsDevice && getTriple().isSPIRV()) 5175 // For HIPSPV map literals to cuda_device (maps to CrossWorkGroup in SPIR-V) 5176 // instead of default AS (maps to Generic in SPIR-V). Otherwise, we end up 5177 // with OpVariable instructions with Generic storage class which is not 5178 // allowed (SPIR-V V1.6 s3.42.8). Also, mapping literals to SPIR-V 5179 // UniformConstant storage class is not viable as pointers to it may not be 5180 // casted to Generic pointers which are used to model HIP's "flat" pointers. 5181 return LangAS::cuda_device; 5182 if (auto AS = getTarget().getConstantAddressSpace()) 5183 return *AS; 5184 return LangAS::Default; 5185 } 5186 5187 // In address space agnostic languages, string literals are in default address 5188 // space in AST. However, certain targets (e.g. amdgcn) request them to be 5189 // emitted in constant address space in LLVM IR. To be consistent with other 5190 // parts of AST, string literal global variables in constant address space 5191 // need to be casted to default address space before being put into address 5192 // map and referenced by other part of CodeGen. 5193 // In OpenCL, string literals are in constant address space in AST, therefore 5194 // they should not be casted to default address space. 5195 static llvm::Constant * 5196 castStringLiteralToDefaultAddressSpace(CodeGenModule &CGM, 5197 llvm::GlobalVariable *GV) { 5198 llvm::Constant *Cast = GV; 5199 if (!CGM.getLangOpts().OpenCL) { 5200 auto AS = CGM.GetGlobalConstantAddressSpace(); 5201 if (AS != LangAS::Default) 5202 Cast = CGM.getTargetCodeGenInfo().performAddrSpaceCast( 5203 CGM, GV, AS, LangAS::Default, 5204 llvm::PointerType::get( 5205 CGM.getLLVMContext(), 5206 CGM.getContext().getTargetAddressSpace(LangAS::Default))); 5207 } 5208 return Cast; 5209 } 5210 5211 template<typename SomeDecl> 5212 void CodeGenModule::MaybeHandleStaticInExternC(const SomeDecl *D, 5213 llvm::GlobalValue *GV) { 5214 if (!getLangOpts().CPlusPlus) 5215 return; 5216 5217 // Must have 'used' attribute, or else inline assembly can't rely on 5218 // the name existing. 5219 if (!D->template hasAttr<UsedAttr>()) 5220 return; 5221 5222 // Must have internal linkage and an ordinary name. 5223 if (!D->getIdentifier() || D->getFormalLinkage() != Linkage::Internal) 5224 return; 5225 5226 // Must be in an extern "C" context. Entities declared directly within 5227 // a record are not extern "C" even if the record is in such a context. 5228 const SomeDecl *First = D->getFirstDecl(); 5229 if (First->getDeclContext()->isRecord() || !First->isInExternCContext()) 5230 return; 5231 5232 // OK, this is an internal linkage entity inside an extern "C" linkage 5233 // specification. Make a note of that so we can give it the "expected" 5234 // mangled name if nothing else is using that name. 5235 std::pair<StaticExternCMap::iterator, bool> R = 5236 StaticExternCValues.insert(std::make_pair(D->getIdentifier(), GV)); 5237 5238 // If we have multiple internal linkage entities with the same name 5239 // in extern "C" regions, none of them gets that name. 5240 if (!R.second) 5241 R.first->second = nullptr; 5242 } 5243 5244 static bool shouldBeInCOMDAT(CodeGenModule &CGM, const Decl &D) { 5245 if (!CGM.supportsCOMDAT()) 5246 return false; 5247 5248 if (D.hasAttr<SelectAnyAttr>()) 5249 return true; 5250 5251 GVALinkage Linkage; 5252 if (auto *VD = dyn_cast<VarDecl>(&D)) 5253 Linkage = CGM.getContext().GetGVALinkageForVariable(VD); 5254 else 5255 Linkage = CGM.getContext().GetGVALinkageForFunction(cast<FunctionDecl>(&D)); 5256 5257 switch (Linkage) { 5258 case GVA_Internal: 5259 case GVA_AvailableExternally: 5260 case GVA_StrongExternal: 5261 return false; 5262 case GVA_DiscardableODR: 5263 case GVA_StrongODR: 5264 return true; 5265 } 5266 llvm_unreachable("No such linkage"); 5267 } 5268 5269 bool CodeGenModule::supportsCOMDAT() const { 5270 return getTriple().supportsCOMDAT(); 5271 } 5272 5273 void CodeGenModule::maybeSetTrivialComdat(const Decl &D, 5274 llvm::GlobalObject &GO) { 5275 if (!shouldBeInCOMDAT(*this, D)) 5276 return; 5277 GO.setComdat(TheModule.getOrInsertComdat(GO.getName())); 5278 } 5279 5280 /// Pass IsTentative as true if you want to create a tentative definition. 5281 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D, 5282 bool IsTentative) { 5283 // OpenCL global variables of sampler type are translated to function calls, 5284 // therefore no need to be translated. 5285 QualType ASTTy = D->getType(); 5286 if (getLangOpts().OpenCL && ASTTy->isSamplerT()) 5287 return; 5288 5289 // If this is OpenMP device, check if it is legal to emit this global 5290 // normally. 5291 if (LangOpts.OpenMPIsTargetDevice && OpenMPRuntime && 5292 OpenMPRuntime->emitTargetGlobalVariable(D)) 5293 return; 5294 5295 llvm::TrackingVH<llvm::Constant> Init; 5296 bool NeedsGlobalCtor = false; 5297 // Whether the definition of the variable is available externally. 5298 // If yes, we shouldn't emit the GloablCtor and GlobalDtor for the variable 5299 // since this is the job for its original source. 5300 bool IsDefinitionAvailableExternally = 5301 getContext().GetGVALinkageForVariable(D) == GVA_AvailableExternally; 5302 bool NeedsGlobalDtor = 5303 !IsDefinitionAvailableExternally && 5304 D->needsDestruction(getContext()) == QualType::DK_cxx_destructor; 5305 5306 const VarDecl *InitDecl; 5307 const Expr *InitExpr = D->getAnyInitializer(InitDecl); 5308 5309 std::optional<ConstantEmitter> emitter; 5310 5311 // CUDA E.2.4.1 "__shared__ variables cannot have an initialization 5312 // as part of their declaration." Sema has already checked for 5313 // error cases, so we just need to set Init to UndefValue. 5314 bool IsCUDASharedVar = 5315 getLangOpts().CUDAIsDevice && D->hasAttr<CUDASharedAttr>(); 5316 // Shadows of initialized device-side global variables are also left 5317 // undefined. 5318 // Managed Variables should be initialized on both host side and device side. 5319 bool IsCUDAShadowVar = 5320 !getLangOpts().CUDAIsDevice && !D->hasAttr<HIPManagedAttr>() && 5321 (D->hasAttr<CUDAConstantAttr>() || D->hasAttr<CUDADeviceAttr>() || 5322 D->hasAttr<CUDASharedAttr>()); 5323 bool IsCUDADeviceShadowVar = 5324 getLangOpts().CUDAIsDevice && !D->hasAttr<HIPManagedAttr>() && 5325 (D->getType()->isCUDADeviceBuiltinSurfaceType() || 5326 D->getType()->isCUDADeviceBuiltinTextureType()); 5327 if (getLangOpts().CUDA && 5328 (IsCUDASharedVar || IsCUDAShadowVar || IsCUDADeviceShadowVar)) 5329 Init = llvm::UndefValue::get(getTypes().ConvertTypeForMem(ASTTy)); 5330 else if (D->hasAttr<LoaderUninitializedAttr>()) 5331 Init = llvm::UndefValue::get(getTypes().ConvertTypeForMem(ASTTy)); 5332 else if (!InitExpr) { 5333 // This is a tentative definition; tentative definitions are 5334 // implicitly initialized with { 0 }. 5335 // 5336 // Note that tentative definitions are only emitted at the end of 5337 // a translation unit, so they should never have incomplete 5338 // type. In addition, EmitTentativeDefinition makes sure that we 5339 // never attempt to emit a tentative definition if a real one 5340 // exists. A use may still exists, however, so we still may need 5341 // to do a RAUW. 5342 assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type"); 5343 Init = EmitNullConstant(D->getType()); 5344 } else { 5345 initializedGlobalDecl = GlobalDecl(D); 5346 emitter.emplace(*this); 5347 llvm::Constant *Initializer = emitter->tryEmitForInitializer(*InitDecl); 5348 if (!Initializer) { 5349 QualType T = InitExpr->getType(); 5350 if (D->getType()->isReferenceType()) 5351 T = D->getType(); 5352 5353 if (getLangOpts().CPlusPlus) { 5354 if (InitDecl->hasFlexibleArrayInit(getContext())) 5355 ErrorUnsupported(D, "flexible array initializer"); 5356 Init = EmitNullConstant(T); 5357 5358 if (!IsDefinitionAvailableExternally) 5359 NeedsGlobalCtor = true; 5360 } else { 5361 ErrorUnsupported(D, "static initializer"); 5362 Init = llvm::UndefValue::get(getTypes().ConvertType(T)); 5363 } 5364 } else { 5365 Init = Initializer; 5366 // We don't need an initializer, so remove the entry for the delayed 5367 // initializer position (just in case this entry was delayed) if we 5368 // also don't need to register a destructor. 5369 if (getLangOpts().CPlusPlus && !NeedsGlobalDtor) 5370 DelayedCXXInitPosition.erase(D); 5371 5372 #ifndef NDEBUG 5373 CharUnits VarSize = getContext().getTypeSizeInChars(ASTTy) + 5374 InitDecl->getFlexibleArrayInitChars(getContext()); 5375 CharUnits CstSize = CharUnits::fromQuantity( 5376 getDataLayout().getTypeAllocSize(Init->getType())); 5377 assert(VarSize == CstSize && "Emitted constant has unexpected size"); 5378 #endif 5379 } 5380 } 5381 5382 llvm::Type* InitType = Init->getType(); 5383 llvm::Constant *Entry = 5384 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)); 5385 5386 // Strip off pointer casts if we got them. 5387 Entry = Entry->stripPointerCasts(); 5388 5389 // Entry is now either a Function or GlobalVariable. 5390 auto *GV = dyn_cast<llvm::GlobalVariable>(Entry); 5391 5392 // We have a definition after a declaration with the wrong type. 5393 // We must make a new GlobalVariable* and update everything that used OldGV 5394 // (a declaration or tentative definition) with the new GlobalVariable* 5395 // (which will be a definition). 5396 // 5397 // This happens if there is a prototype for a global (e.g. 5398 // "extern int x[];") and then a definition of a different type (e.g. 5399 // "int x[10];"). This also happens when an initializer has a different type 5400 // from the type of the global (this happens with unions). 5401 if (!GV || GV->getValueType() != InitType || 5402 GV->getType()->getAddressSpace() != 5403 getContext().getTargetAddressSpace(GetGlobalVarAddressSpace(D))) { 5404 5405 // Move the old entry aside so that we'll create a new one. 5406 Entry->setName(StringRef()); 5407 5408 // Make a new global with the correct type, this is now guaranteed to work. 5409 GV = cast<llvm::GlobalVariable>( 5410 GetAddrOfGlobalVar(D, InitType, ForDefinition_t(!IsTentative)) 5411 ->stripPointerCasts()); 5412 5413 // Replace all uses of the old global with the new global 5414 llvm::Constant *NewPtrForOldDecl = 5415 llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, 5416 Entry->getType()); 5417 Entry->replaceAllUsesWith(NewPtrForOldDecl); 5418 5419 // Erase the old global, since it is no longer used. 5420 cast<llvm::GlobalValue>(Entry)->eraseFromParent(); 5421 } 5422 5423 MaybeHandleStaticInExternC(D, GV); 5424 5425 if (D->hasAttr<AnnotateAttr>()) 5426 AddGlobalAnnotations(D, GV); 5427 5428 // Set the llvm linkage type as appropriate. 5429 llvm::GlobalValue::LinkageTypes Linkage = getLLVMLinkageVarDefinition(D); 5430 5431 // CUDA B.2.1 "The __device__ qualifier declares a variable that resides on 5432 // the device. [...]" 5433 // CUDA B.2.2 "The __constant__ qualifier, optionally used together with 5434 // __device__, declares a variable that: [...] 5435 // Is accessible from all the threads within the grid and from the host 5436 // through the runtime library (cudaGetSymbolAddress() / cudaGetSymbolSize() 5437 // / cudaMemcpyToSymbol() / cudaMemcpyFromSymbol())." 5438 if (LangOpts.CUDA) { 5439 if (LangOpts.CUDAIsDevice) { 5440 if (Linkage != llvm::GlobalValue::InternalLinkage && 5441 (D->hasAttr<CUDADeviceAttr>() || D->hasAttr<CUDAConstantAttr>() || 5442 D->getType()->isCUDADeviceBuiltinSurfaceType() || 5443 D->getType()->isCUDADeviceBuiltinTextureType())) 5444 GV->setExternallyInitialized(true); 5445 } else { 5446 getCUDARuntime().internalizeDeviceSideVar(D, Linkage); 5447 } 5448 getCUDARuntime().handleVarRegistration(D, *GV); 5449 } 5450 5451 GV->setInitializer(Init); 5452 if (emitter) 5453 emitter->finalize(GV); 5454 5455 // If it is safe to mark the global 'constant', do so now. 5456 GV->setConstant(!NeedsGlobalCtor && !NeedsGlobalDtor && 5457 D->getType().isConstantStorage(getContext(), true, true)); 5458 5459 // If it is in a read-only section, mark it 'constant'. 5460 if (const SectionAttr *SA = D->getAttr<SectionAttr>()) { 5461 const ASTContext::SectionInfo &SI = Context.SectionInfos[SA->getName()]; 5462 if ((SI.SectionFlags & ASTContext::PSF_Write) == 0) 5463 GV->setConstant(true); 5464 } 5465 5466 CharUnits AlignVal = getContext().getDeclAlign(D); 5467 // Check for alignment specifed in an 'omp allocate' directive. 5468 if (std::optional<CharUnits> AlignValFromAllocate = 5469 getOMPAllocateAlignment(D)) 5470 AlignVal = *AlignValFromAllocate; 5471 GV->setAlignment(AlignVal.getAsAlign()); 5472 5473 // On Darwin, unlike other Itanium C++ ABI platforms, the thread-wrapper 5474 // function is only defined alongside the variable, not also alongside 5475 // callers. Normally, all accesses to a thread_local go through the 5476 // thread-wrapper in order to ensure initialization has occurred, underlying 5477 // variable will never be used other than the thread-wrapper, so it can be 5478 // converted to internal linkage. 5479 // 5480 // However, if the variable has the 'constinit' attribute, it _can_ be 5481 // referenced directly, without calling the thread-wrapper, so the linkage 5482 // must not be changed. 5483 // 5484 // Additionally, if the variable isn't plain external linkage, e.g. if it's 5485 // weak or linkonce, the de-duplication semantics are important to preserve, 5486 // so we don't change the linkage. 5487 if (D->getTLSKind() == VarDecl::TLS_Dynamic && 5488 Linkage == llvm::GlobalValue::ExternalLinkage && 5489 Context.getTargetInfo().getTriple().isOSDarwin() && 5490 !D->hasAttr<ConstInitAttr>()) 5491 Linkage = llvm::GlobalValue::InternalLinkage; 5492 5493 GV->setLinkage(Linkage); 5494 if (D->hasAttr<DLLImportAttr>()) 5495 GV->setDLLStorageClass(llvm::GlobalVariable::DLLImportStorageClass); 5496 else if (D->hasAttr<DLLExportAttr>()) 5497 GV->setDLLStorageClass(llvm::GlobalVariable::DLLExportStorageClass); 5498 else 5499 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass); 5500 5501 if (Linkage == llvm::GlobalVariable::CommonLinkage) { 5502 // common vars aren't constant even if declared const. 5503 GV->setConstant(false); 5504 // Tentative definition of global variables may be initialized with 5505 // non-zero null pointers. In this case they should have weak linkage 5506 // since common linkage must have zero initializer and must not have 5507 // explicit section therefore cannot have non-zero initial value. 5508 if (!GV->getInitializer()->isNullValue()) 5509 GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage); 5510 } 5511 5512 setNonAliasAttributes(D, GV); 5513 5514 if (D->getTLSKind() && !GV->isThreadLocal()) { 5515 if (D->getTLSKind() == VarDecl::TLS_Dynamic) 5516 CXXThreadLocals.push_back(D); 5517 setTLSMode(GV, *D); 5518 } 5519 5520 maybeSetTrivialComdat(*D, *GV); 5521 5522 // Emit the initializer function if necessary. 5523 if (NeedsGlobalCtor || NeedsGlobalDtor) 5524 EmitCXXGlobalVarDeclInitFunc(D, GV, NeedsGlobalCtor); 5525 5526 SanitizerMD->reportGlobal(GV, *D, NeedsGlobalCtor); 5527 5528 // Emit global variable debug information. 5529 if (CGDebugInfo *DI = getModuleDebugInfo()) 5530 if (getCodeGenOpts().hasReducedDebugInfo()) 5531 DI->EmitGlobalVariable(GV, D); 5532 } 5533 5534 void CodeGenModule::EmitExternalVarDeclaration(const VarDecl *D) { 5535 if (CGDebugInfo *DI = getModuleDebugInfo()) 5536 if (getCodeGenOpts().hasReducedDebugInfo()) { 5537 QualType ASTTy = D->getType(); 5538 llvm::Type *Ty = getTypes().ConvertTypeForMem(D->getType()); 5539 llvm::Constant *GV = 5540 GetOrCreateLLVMGlobal(D->getName(), Ty, ASTTy.getAddressSpace(), D); 5541 DI->EmitExternalVariable( 5542 cast<llvm::GlobalVariable>(GV->stripPointerCasts()), D); 5543 } 5544 } 5545 5546 static bool isVarDeclStrongDefinition(const ASTContext &Context, 5547 CodeGenModule &CGM, const VarDecl *D, 5548 bool NoCommon) { 5549 // Don't give variables common linkage if -fno-common was specified unless it 5550 // was overridden by a NoCommon attribute. 5551 if ((NoCommon || D->hasAttr<NoCommonAttr>()) && !D->hasAttr<CommonAttr>()) 5552 return true; 5553 5554 // C11 6.9.2/2: 5555 // A declaration of an identifier for an object that has file scope without 5556 // an initializer, and without a storage-class specifier or with the 5557 // storage-class specifier static, constitutes a tentative definition. 5558 if (D->getInit() || D->hasExternalStorage()) 5559 return true; 5560 5561 // A variable cannot be both common and exist in a section. 5562 if (D->hasAttr<SectionAttr>()) 5563 return true; 5564 5565 // A variable cannot be both common and exist in a section. 5566 // We don't try to determine which is the right section in the front-end. 5567 // If no specialized section name is applicable, it will resort to default. 5568 if (D->hasAttr<PragmaClangBSSSectionAttr>() || 5569 D->hasAttr<PragmaClangDataSectionAttr>() || 5570 D->hasAttr<PragmaClangRelroSectionAttr>() || 5571 D->hasAttr<PragmaClangRodataSectionAttr>()) 5572 return true; 5573 5574 // Thread local vars aren't considered common linkage. 5575 if (D->getTLSKind()) 5576 return true; 5577 5578 // Tentative definitions marked with WeakImportAttr are true definitions. 5579 if (D->hasAttr<WeakImportAttr>()) 5580 return true; 5581 5582 // A variable cannot be both common and exist in a comdat. 5583 if (shouldBeInCOMDAT(CGM, *D)) 5584 return true; 5585 5586 // Declarations with a required alignment do not have common linkage in MSVC 5587 // mode. 5588 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) { 5589 if (D->hasAttr<AlignedAttr>()) 5590 return true; 5591 QualType VarType = D->getType(); 5592 if (Context.isAlignmentRequired(VarType)) 5593 return true; 5594 5595 if (const auto *RT = VarType->getAs<RecordType>()) { 5596 const RecordDecl *RD = RT->getDecl(); 5597 for (const FieldDecl *FD : RD->fields()) { 5598 if (FD->isBitField()) 5599 continue; 5600 if (FD->hasAttr<AlignedAttr>()) 5601 return true; 5602 if (Context.isAlignmentRequired(FD->getType())) 5603 return true; 5604 } 5605 } 5606 } 5607 5608 // Microsoft's link.exe doesn't support alignments greater than 32 bytes for 5609 // common symbols, so symbols with greater alignment requirements cannot be 5610 // common. 5611 // Other COFF linkers (ld.bfd and LLD) support arbitrary power-of-two 5612 // alignments for common symbols via the aligncomm directive, so this 5613 // restriction only applies to MSVC environments. 5614 if (Context.getTargetInfo().getTriple().isKnownWindowsMSVCEnvironment() && 5615 Context.getTypeAlignIfKnown(D->getType()) > 5616 Context.toBits(CharUnits::fromQuantity(32))) 5617 return true; 5618 5619 return false; 5620 } 5621 5622 llvm::GlobalValue::LinkageTypes 5623 CodeGenModule::getLLVMLinkageForDeclarator(const DeclaratorDecl *D, 5624 GVALinkage Linkage) { 5625 if (Linkage == GVA_Internal) 5626 return llvm::Function::InternalLinkage; 5627 5628 if (D->hasAttr<WeakAttr>()) 5629 return llvm::GlobalVariable::WeakAnyLinkage; 5630 5631 if (const auto *FD = D->getAsFunction()) 5632 if (FD->isMultiVersion() && Linkage == GVA_AvailableExternally) 5633 return llvm::GlobalVariable::LinkOnceAnyLinkage; 5634 5635 // We are guaranteed to have a strong definition somewhere else, 5636 // so we can use available_externally linkage. 5637 if (Linkage == GVA_AvailableExternally) 5638 return llvm::GlobalValue::AvailableExternallyLinkage; 5639 5640 // Note that Apple's kernel linker doesn't support symbol 5641 // coalescing, so we need to avoid linkonce and weak linkages there. 5642 // Normally, this means we just map to internal, but for explicit 5643 // instantiations we'll map to external. 5644 5645 // In C++, the compiler has to emit a definition in every translation unit 5646 // that references the function. We should use linkonce_odr because 5647 // a) if all references in this translation unit are optimized away, we 5648 // don't need to codegen it. b) if the function persists, it needs to be 5649 // merged with other definitions. c) C++ has the ODR, so we know the 5650 // definition is dependable. 5651 if (Linkage == GVA_DiscardableODR) 5652 return !Context.getLangOpts().AppleKext ? llvm::Function::LinkOnceODRLinkage 5653 : llvm::Function::InternalLinkage; 5654 5655 // An explicit instantiation of a template has weak linkage, since 5656 // explicit instantiations can occur in multiple translation units 5657 // and must all be equivalent. However, we are not allowed to 5658 // throw away these explicit instantiations. 5659 // 5660 // CUDA/HIP: For -fno-gpu-rdc case, device code is limited to one TU, 5661 // so say that CUDA templates are either external (for kernels) or internal. 5662 // This lets llvm perform aggressive inter-procedural optimizations. For 5663 // -fgpu-rdc case, device function calls across multiple TU's are allowed, 5664 // therefore we need to follow the normal linkage paradigm. 5665 if (Linkage == GVA_StrongODR) { 5666 if (getLangOpts().AppleKext) 5667 return llvm::Function::ExternalLinkage; 5668 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice && 5669 !getLangOpts().GPURelocatableDeviceCode) 5670 return D->hasAttr<CUDAGlobalAttr>() ? llvm::Function::ExternalLinkage 5671 : llvm::Function::InternalLinkage; 5672 return llvm::Function::WeakODRLinkage; 5673 } 5674 5675 // C++ doesn't have tentative definitions and thus cannot have common 5676 // linkage. 5677 if (!getLangOpts().CPlusPlus && isa<VarDecl>(D) && 5678 !isVarDeclStrongDefinition(Context, *this, cast<VarDecl>(D), 5679 CodeGenOpts.NoCommon)) 5680 return llvm::GlobalVariable::CommonLinkage; 5681 5682 // selectany symbols are externally visible, so use weak instead of 5683 // linkonce. MSVC optimizes away references to const selectany globals, so 5684 // all definitions should be the same and ODR linkage should be used. 5685 // http://msdn.microsoft.com/en-us/library/5tkz6s71.aspx 5686 if (D->hasAttr<SelectAnyAttr>()) 5687 return llvm::GlobalVariable::WeakODRLinkage; 5688 5689 // Otherwise, we have strong external linkage. 5690 assert(Linkage == GVA_StrongExternal); 5691 return llvm::GlobalVariable::ExternalLinkage; 5692 } 5693 5694 llvm::GlobalValue::LinkageTypes 5695 CodeGenModule::getLLVMLinkageVarDefinition(const VarDecl *VD) { 5696 GVALinkage Linkage = getContext().GetGVALinkageForVariable(VD); 5697 return getLLVMLinkageForDeclarator(VD, Linkage); 5698 } 5699 5700 /// Replace the uses of a function that was declared with a non-proto type. 5701 /// We want to silently drop extra arguments from call sites 5702 static void replaceUsesOfNonProtoConstant(llvm::Constant *old, 5703 llvm::Function *newFn) { 5704 // Fast path. 5705 if (old->use_empty()) return; 5706 5707 llvm::Type *newRetTy = newFn->getReturnType(); 5708 SmallVector<llvm::Value*, 4> newArgs; 5709 5710 for (llvm::Value::use_iterator ui = old->use_begin(), ue = old->use_end(); 5711 ui != ue; ) { 5712 llvm::Value::use_iterator use = ui++; // Increment before the use is erased. 5713 llvm::User *user = use->getUser(); 5714 5715 // Recognize and replace uses of bitcasts. Most calls to 5716 // unprototyped functions will use bitcasts. 5717 if (auto *bitcast = dyn_cast<llvm::ConstantExpr>(user)) { 5718 if (bitcast->getOpcode() == llvm::Instruction::BitCast) 5719 replaceUsesOfNonProtoConstant(bitcast, newFn); 5720 continue; 5721 } 5722 5723 // Recognize calls to the function. 5724 llvm::CallBase *callSite = dyn_cast<llvm::CallBase>(user); 5725 if (!callSite) continue; 5726 if (!callSite->isCallee(&*use)) 5727 continue; 5728 5729 // If the return types don't match exactly, then we can't 5730 // transform this call unless it's dead. 5731 if (callSite->getType() != newRetTy && !callSite->use_empty()) 5732 continue; 5733 5734 // Get the call site's attribute list. 5735 SmallVector<llvm::AttributeSet, 8> newArgAttrs; 5736 llvm::AttributeList oldAttrs = callSite->getAttributes(); 5737 5738 // If the function was passed too few arguments, don't transform. 5739 unsigned newNumArgs = newFn->arg_size(); 5740 if (callSite->arg_size() < newNumArgs) 5741 continue; 5742 5743 // If extra arguments were passed, we silently drop them. 5744 // If any of the types mismatch, we don't transform. 5745 unsigned argNo = 0; 5746 bool dontTransform = false; 5747 for (llvm::Argument &A : newFn->args()) { 5748 if (callSite->getArgOperand(argNo)->getType() != A.getType()) { 5749 dontTransform = true; 5750 break; 5751 } 5752 5753 // Add any parameter attributes. 5754 newArgAttrs.push_back(oldAttrs.getParamAttrs(argNo)); 5755 argNo++; 5756 } 5757 if (dontTransform) 5758 continue; 5759 5760 // Okay, we can transform this. Create the new call instruction and copy 5761 // over the required information. 5762 newArgs.append(callSite->arg_begin(), callSite->arg_begin() + argNo); 5763 5764 // Copy over any operand bundles. 5765 SmallVector<llvm::OperandBundleDef, 1> newBundles; 5766 callSite->getOperandBundlesAsDefs(newBundles); 5767 5768 llvm::CallBase *newCall; 5769 if (isa<llvm::CallInst>(callSite)) { 5770 newCall = 5771 llvm::CallInst::Create(newFn, newArgs, newBundles, "", callSite); 5772 } else { 5773 auto *oldInvoke = cast<llvm::InvokeInst>(callSite); 5774 newCall = llvm::InvokeInst::Create(newFn, oldInvoke->getNormalDest(), 5775 oldInvoke->getUnwindDest(), newArgs, 5776 newBundles, "", callSite); 5777 } 5778 newArgs.clear(); // for the next iteration 5779 5780 if (!newCall->getType()->isVoidTy()) 5781 newCall->takeName(callSite); 5782 newCall->setAttributes( 5783 llvm::AttributeList::get(newFn->getContext(), oldAttrs.getFnAttrs(), 5784 oldAttrs.getRetAttrs(), newArgAttrs)); 5785 newCall->setCallingConv(callSite->getCallingConv()); 5786 5787 // Finally, remove the old call, replacing any uses with the new one. 5788 if (!callSite->use_empty()) 5789 callSite->replaceAllUsesWith(newCall); 5790 5791 // Copy debug location attached to CI. 5792 if (callSite->getDebugLoc()) 5793 newCall->setDebugLoc(callSite->getDebugLoc()); 5794 5795 callSite->eraseFromParent(); 5796 } 5797 } 5798 5799 /// ReplaceUsesOfNonProtoTypeWithRealFunction - This function is called when we 5800 /// implement a function with no prototype, e.g. "int foo() {}". If there are 5801 /// existing call uses of the old function in the module, this adjusts them to 5802 /// call the new function directly. 5803 /// 5804 /// This is not just a cleanup: the always_inline pass requires direct calls to 5805 /// functions to be able to inline them. If there is a bitcast in the way, it 5806 /// won't inline them. Instcombine normally deletes these calls, but it isn't 5807 /// run at -O0. 5808 static void ReplaceUsesOfNonProtoTypeWithRealFunction(llvm::GlobalValue *Old, 5809 llvm::Function *NewFn) { 5810 // If we're redefining a global as a function, don't transform it. 5811 if (!isa<llvm::Function>(Old)) return; 5812 5813 replaceUsesOfNonProtoConstant(Old, NewFn); 5814 } 5815 5816 void CodeGenModule::HandleCXXStaticMemberVarInstantiation(VarDecl *VD) { 5817 auto DK = VD->isThisDeclarationADefinition(); 5818 if (DK == VarDecl::Definition && VD->hasAttr<DLLImportAttr>()) 5819 return; 5820 5821 TemplateSpecializationKind TSK = VD->getTemplateSpecializationKind(); 5822 // If we have a definition, this might be a deferred decl. If the 5823 // instantiation is explicit, make sure we emit it at the end. 5824 if (VD->getDefinition() && TSK == TSK_ExplicitInstantiationDefinition) 5825 GetAddrOfGlobalVar(VD); 5826 5827 EmitTopLevelDecl(VD); 5828 } 5829 5830 void CodeGenModule::EmitGlobalFunctionDefinition(GlobalDecl GD, 5831 llvm::GlobalValue *GV) { 5832 const auto *D = cast<FunctionDecl>(GD.getDecl()); 5833 5834 // Compute the function info and LLVM type. 5835 const CGFunctionInfo &FI = getTypes().arrangeGlobalDeclaration(GD); 5836 llvm::FunctionType *Ty = getTypes().GetFunctionType(FI); 5837 5838 // Get or create the prototype for the function. 5839 if (!GV || (GV->getValueType() != Ty)) 5840 GV = cast<llvm::GlobalValue>(GetAddrOfFunction(GD, Ty, /*ForVTable=*/false, 5841 /*DontDefer=*/true, 5842 ForDefinition)); 5843 5844 // Already emitted. 5845 if (!GV->isDeclaration()) 5846 return; 5847 5848 // We need to set linkage and visibility on the function before 5849 // generating code for it because various parts of IR generation 5850 // want to propagate this information down (e.g. to local static 5851 // declarations). 5852 auto *Fn = cast<llvm::Function>(GV); 5853 setFunctionLinkage(GD, Fn); 5854 5855 // FIXME: this is redundant with part of setFunctionDefinitionAttributes 5856 setGVProperties(Fn, GD); 5857 5858 MaybeHandleStaticInExternC(D, Fn); 5859 5860 maybeSetTrivialComdat(*D, *Fn); 5861 5862 CodeGenFunction(*this).GenerateCode(GD, Fn, FI); 5863 5864 setNonAliasAttributes(GD, Fn); 5865 SetLLVMFunctionAttributesForDefinition(D, Fn); 5866 5867 if (const ConstructorAttr *CA = D->getAttr<ConstructorAttr>()) 5868 AddGlobalCtor(Fn, CA->getPriority()); 5869 if (const DestructorAttr *DA = D->getAttr<DestructorAttr>()) 5870 AddGlobalDtor(Fn, DA->getPriority(), true); 5871 if (getLangOpts().OpenMP && D->hasAttr<OMPDeclareTargetDeclAttr>()) 5872 getOpenMPRuntime().emitDeclareTargetFunction(D, GV); 5873 } 5874 5875 void CodeGenModule::EmitAliasDefinition(GlobalDecl GD) { 5876 const auto *D = cast<ValueDecl>(GD.getDecl()); 5877 const AliasAttr *AA = D->getAttr<AliasAttr>(); 5878 assert(AA && "Not an alias?"); 5879 5880 StringRef MangledName = getMangledName(GD); 5881 5882 if (AA->getAliasee() == MangledName) { 5883 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0; 5884 return; 5885 } 5886 5887 // If there is a definition in the module, then it wins over the alias. 5888 // This is dubious, but allow it to be safe. Just ignore the alias. 5889 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 5890 if (Entry && !Entry->isDeclaration()) 5891 return; 5892 5893 Aliases.push_back(GD); 5894 5895 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 5896 5897 // Create a reference to the named value. This ensures that it is emitted 5898 // if a deferred decl. 5899 llvm::Constant *Aliasee; 5900 llvm::GlobalValue::LinkageTypes LT; 5901 if (isa<llvm::FunctionType>(DeclTy)) { 5902 Aliasee = GetOrCreateLLVMFunction(AA->getAliasee(), DeclTy, GD, 5903 /*ForVTable=*/false); 5904 LT = getFunctionLinkage(GD); 5905 } else { 5906 Aliasee = GetOrCreateLLVMGlobal(AA->getAliasee(), DeclTy, LangAS::Default, 5907 /*D=*/nullptr); 5908 if (const auto *VD = dyn_cast<VarDecl>(GD.getDecl())) 5909 LT = getLLVMLinkageVarDefinition(VD); 5910 else 5911 LT = getFunctionLinkage(GD); 5912 } 5913 5914 // Create the new alias itself, but don't set a name yet. 5915 unsigned AS = Aliasee->getType()->getPointerAddressSpace(); 5916 auto *GA = 5917 llvm::GlobalAlias::create(DeclTy, AS, LT, "", Aliasee, &getModule()); 5918 5919 if (Entry) { 5920 if (GA->getAliasee() == Entry) { 5921 Diags.Report(AA->getLocation(), diag::err_cyclic_alias) << 0; 5922 return; 5923 } 5924 5925 assert(Entry->isDeclaration()); 5926 5927 // If there is a declaration in the module, then we had an extern followed 5928 // by the alias, as in: 5929 // extern int test6(); 5930 // ... 5931 // int test6() __attribute__((alias("test7"))); 5932 // 5933 // Remove it and replace uses of it with the alias. 5934 GA->takeName(Entry); 5935 5936 Entry->replaceAllUsesWith(GA); 5937 Entry->eraseFromParent(); 5938 } else { 5939 GA->setName(MangledName); 5940 } 5941 5942 // Set attributes which are particular to an alias; this is a 5943 // specialization of the attributes which may be set on a global 5944 // variable/function. 5945 if (D->hasAttr<WeakAttr>() || D->hasAttr<WeakRefAttr>() || 5946 D->isWeakImported()) { 5947 GA->setLinkage(llvm::Function::WeakAnyLinkage); 5948 } 5949 5950 if (const auto *VD = dyn_cast<VarDecl>(D)) 5951 if (VD->getTLSKind()) 5952 setTLSMode(GA, *VD); 5953 5954 SetCommonAttributes(GD, GA); 5955 5956 // Emit global alias debug information. 5957 if (isa<VarDecl>(D)) 5958 if (CGDebugInfo *DI = getModuleDebugInfo()) 5959 DI->EmitGlobalAlias(cast<llvm::GlobalValue>(GA->getAliasee()->stripPointerCasts()), GD); 5960 } 5961 5962 void CodeGenModule::emitIFuncDefinition(GlobalDecl GD) { 5963 const auto *D = cast<ValueDecl>(GD.getDecl()); 5964 const IFuncAttr *IFA = D->getAttr<IFuncAttr>(); 5965 assert(IFA && "Not an ifunc?"); 5966 5967 StringRef MangledName = getMangledName(GD); 5968 5969 if (IFA->getResolver() == MangledName) { 5970 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1; 5971 return; 5972 } 5973 5974 // Report an error if some definition overrides ifunc. 5975 llvm::GlobalValue *Entry = GetGlobalValue(MangledName); 5976 if (Entry && !Entry->isDeclaration()) { 5977 GlobalDecl OtherGD; 5978 if (lookupRepresentativeDecl(MangledName, OtherGD) && 5979 DiagnosedConflictingDefinitions.insert(GD).second) { 5980 Diags.Report(D->getLocation(), diag::err_duplicate_mangled_name) 5981 << MangledName; 5982 Diags.Report(OtherGD.getDecl()->getLocation(), 5983 diag::note_previous_definition); 5984 } 5985 return; 5986 } 5987 5988 Aliases.push_back(GD); 5989 5990 llvm::Type *DeclTy = getTypes().ConvertTypeForMem(D->getType()); 5991 llvm::Type *ResolverTy = llvm::GlobalIFunc::getResolverFunctionType(DeclTy); 5992 llvm::Constant *Resolver = 5993 GetOrCreateLLVMFunction(IFA->getResolver(), ResolverTy, {}, 5994 /*ForVTable=*/false); 5995 llvm::GlobalIFunc *GIF = 5996 llvm::GlobalIFunc::create(DeclTy, 0, llvm::Function::ExternalLinkage, 5997 "", Resolver, &getModule()); 5998 if (Entry) { 5999 if (GIF->getResolver() == Entry) { 6000 Diags.Report(IFA->getLocation(), diag::err_cyclic_alias) << 1; 6001 return; 6002 } 6003 assert(Entry->isDeclaration()); 6004 6005 // If there is a declaration in the module, then we had an extern followed 6006 // by the ifunc, as in: 6007 // extern int test(); 6008 // ... 6009 // int test() __attribute__((ifunc("resolver"))); 6010 // 6011 // Remove it and replace uses of it with the ifunc. 6012 GIF->takeName(Entry); 6013 6014 Entry->replaceAllUsesWith(GIF); 6015 Entry->eraseFromParent(); 6016 } else 6017 GIF->setName(MangledName); 6018 if (auto *F = dyn_cast<llvm::Function>(Resolver)) { 6019 F->addFnAttr(llvm::Attribute::DisableSanitizerInstrumentation); 6020 } 6021 SetCommonAttributes(GD, GIF); 6022 } 6023 6024 llvm::Function *CodeGenModule::getIntrinsic(unsigned IID, 6025 ArrayRef<llvm::Type*> Tys) { 6026 return llvm::Intrinsic::getDeclaration(&getModule(), (llvm::Intrinsic::ID)IID, 6027 Tys); 6028 } 6029 6030 static llvm::StringMapEntry<llvm::GlobalVariable *> & 6031 GetConstantCFStringEntry(llvm::StringMap<llvm::GlobalVariable *> &Map, 6032 const StringLiteral *Literal, bool TargetIsLSB, 6033 bool &IsUTF16, unsigned &StringLength) { 6034 StringRef String = Literal->getString(); 6035 unsigned NumBytes = String.size(); 6036 6037 // Check for simple case. 6038 if (!Literal->containsNonAsciiOrNull()) { 6039 StringLength = NumBytes; 6040 return *Map.insert(std::make_pair(String, nullptr)).first; 6041 } 6042 6043 // Otherwise, convert the UTF8 literals into a string of shorts. 6044 IsUTF16 = true; 6045 6046 SmallVector<llvm::UTF16, 128> ToBuf(NumBytes + 1); // +1 for ending nulls. 6047 const llvm::UTF8 *FromPtr = (const llvm::UTF8 *)String.data(); 6048 llvm::UTF16 *ToPtr = &ToBuf[0]; 6049 6050 (void)llvm::ConvertUTF8toUTF16(&FromPtr, FromPtr + NumBytes, &ToPtr, 6051 ToPtr + NumBytes, llvm::strictConversion); 6052 6053 // ConvertUTF8toUTF16 returns the length in ToPtr. 6054 StringLength = ToPtr - &ToBuf[0]; 6055 6056 // Add an explicit null. 6057 *ToPtr = 0; 6058 return *Map.insert(std::make_pair( 6059 StringRef(reinterpret_cast<const char *>(ToBuf.data()), 6060 (StringLength + 1) * 2), 6061 nullptr)).first; 6062 } 6063 6064 ConstantAddress 6065 CodeGenModule::GetAddrOfConstantCFString(const StringLiteral *Literal) { 6066 unsigned StringLength = 0; 6067 bool isUTF16 = false; 6068 llvm::StringMapEntry<llvm::GlobalVariable *> &Entry = 6069 GetConstantCFStringEntry(CFConstantStringMap, Literal, 6070 getDataLayout().isLittleEndian(), isUTF16, 6071 StringLength); 6072 6073 if (auto *C = Entry.second) 6074 return ConstantAddress( 6075 C, C->getValueType(), CharUnits::fromQuantity(C->getAlignment())); 6076 6077 llvm::Constant *Zero = llvm::Constant::getNullValue(Int32Ty); 6078 llvm::Constant *Zeros[] = { Zero, Zero }; 6079 6080 const ASTContext &Context = getContext(); 6081 const llvm::Triple &Triple = getTriple(); 6082 6083 const auto CFRuntime = getLangOpts().CFRuntime; 6084 const bool IsSwiftABI = 6085 static_cast<unsigned>(CFRuntime) >= 6086 static_cast<unsigned>(LangOptions::CoreFoundationABI::Swift); 6087 const bool IsSwift4_1 = CFRuntime == LangOptions::CoreFoundationABI::Swift4_1; 6088 6089 // If we don't already have it, get __CFConstantStringClassReference. 6090 if (!CFConstantStringClassRef) { 6091 const char *CFConstantStringClassName = "__CFConstantStringClassReference"; 6092 llvm::Type *Ty = getTypes().ConvertType(getContext().IntTy); 6093 Ty = llvm::ArrayType::get(Ty, 0); 6094 6095 switch (CFRuntime) { 6096 default: break; 6097 case LangOptions::CoreFoundationABI::Swift: [[fallthrough]]; 6098 case LangOptions::CoreFoundationABI::Swift5_0: 6099 CFConstantStringClassName = 6100 Triple.isOSDarwin() ? "$s15SwiftFoundation19_NSCFConstantStringCN" 6101 : "$s10Foundation19_NSCFConstantStringCN"; 6102 Ty = IntPtrTy; 6103 break; 6104 case LangOptions::CoreFoundationABI::Swift4_2: 6105 CFConstantStringClassName = 6106 Triple.isOSDarwin() ? "$S15SwiftFoundation19_NSCFConstantStringCN" 6107 : "$S10Foundation19_NSCFConstantStringCN"; 6108 Ty = IntPtrTy; 6109 break; 6110 case LangOptions::CoreFoundationABI::Swift4_1: 6111 CFConstantStringClassName = 6112 Triple.isOSDarwin() ? "__T015SwiftFoundation19_NSCFConstantStringCN" 6113 : "__T010Foundation19_NSCFConstantStringCN"; 6114 Ty = IntPtrTy; 6115 break; 6116 } 6117 6118 llvm::Constant *C = CreateRuntimeVariable(Ty, CFConstantStringClassName); 6119 6120 if (Triple.isOSBinFormatELF() || Triple.isOSBinFormatCOFF()) { 6121 llvm::GlobalValue *GV = nullptr; 6122 6123 if ((GV = dyn_cast<llvm::GlobalValue>(C))) { 6124 IdentifierInfo &II = Context.Idents.get(GV->getName()); 6125 TranslationUnitDecl *TUDecl = Context.getTranslationUnitDecl(); 6126 DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl); 6127 6128 const VarDecl *VD = nullptr; 6129 for (const auto *Result : DC->lookup(&II)) 6130 if ((VD = dyn_cast<VarDecl>(Result))) 6131 break; 6132 6133 if (Triple.isOSBinFormatELF()) { 6134 if (!VD) 6135 GV->setLinkage(llvm::GlobalValue::ExternalLinkage); 6136 } else { 6137 GV->setLinkage(llvm::GlobalValue::ExternalLinkage); 6138 if (!VD || !VD->hasAttr<DLLExportAttr>()) 6139 GV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass); 6140 else 6141 GV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass); 6142 } 6143 6144 setDSOLocal(GV); 6145 } 6146 } 6147 6148 // Decay array -> ptr 6149 CFConstantStringClassRef = 6150 IsSwiftABI ? llvm::ConstantExpr::getPtrToInt(C, Ty) 6151 : llvm::ConstantExpr::getGetElementPtr(Ty, C, Zeros); 6152 } 6153 6154 QualType CFTy = Context.getCFConstantStringType(); 6155 6156 auto *STy = cast<llvm::StructType>(getTypes().ConvertType(CFTy)); 6157 6158 ConstantInitBuilder Builder(*this); 6159 auto Fields = Builder.beginStruct(STy); 6160 6161 // Class pointer. 6162 Fields.add(cast<llvm::Constant>(CFConstantStringClassRef)); 6163 6164 // Flags. 6165 if (IsSwiftABI) { 6166 Fields.addInt(IntPtrTy, IsSwift4_1 ? 0x05 : 0x01); 6167 Fields.addInt(Int64Ty, isUTF16 ? 0x07d0 : 0x07c8); 6168 } else { 6169 Fields.addInt(IntTy, isUTF16 ? 0x07d0 : 0x07C8); 6170 } 6171 6172 // String pointer. 6173 llvm::Constant *C = nullptr; 6174 if (isUTF16) { 6175 auto Arr = llvm::ArrayRef( 6176 reinterpret_cast<uint16_t *>(const_cast<char *>(Entry.first().data())), 6177 Entry.first().size() / 2); 6178 C = llvm::ConstantDataArray::get(VMContext, Arr); 6179 } else { 6180 C = llvm::ConstantDataArray::getString(VMContext, Entry.first()); 6181 } 6182 6183 // Note: -fwritable-strings doesn't make the backing store strings of 6184 // CFStrings writable. 6185 auto *GV = 6186 new llvm::GlobalVariable(getModule(), C->getType(), /*isConstant=*/true, 6187 llvm::GlobalValue::PrivateLinkage, C, ".str"); 6188 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 6189 // Don't enforce the target's minimum global alignment, since the only use 6190 // of the string is via this class initializer. 6191 CharUnits Align = isUTF16 ? Context.getTypeAlignInChars(Context.ShortTy) 6192 : Context.getTypeAlignInChars(Context.CharTy); 6193 GV->setAlignment(Align.getAsAlign()); 6194 6195 // FIXME: We set the section explicitly to avoid a bug in ld64 224.1. 6196 // Without it LLVM can merge the string with a non unnamed_addr one during 6197 // LTO. Doing that changes the section it ends in, which surprises ld64. 6198 if (Triple.isOSBinFormatMachO()) 6199 GV->setSection(isUTF16 ? "__TEXT,__ustring" 6200 : "__TEXT,__cstring,cstring_literals"); 6201 // Make sure the literal ends up in .rodata to allow for safe ICF and for 6202 // the static linker to adjust permissions to read-only later on. 6203 else if (Triple.isOSBinFormatELF()) 6204 GV->setSection(".rodata"); 6205 6206 // String. 6207 llvm::Constant *Str = 6208 llvm::ConstantExpr::getGetElementPtr(GV->getValueType(), GV, Zeros); 6209 6210 Fields.add(Str); 6211 6212 // String length. 6213 llvm::IntegerType *LengthTy = 6214 llvm::IntegerType::get(getModule().getContext(), 6215 Context.getTargetInfo().getLongWidth()); 6216 if (IsSwiftABI) { 6217 if (CFRuntime == LangOptions::CoreFoundationABI::Swift4_1 || 6218 CFRuntime == LangOptions::CoreFoundationABI::Swift4_2) 6219 LengthTy = Int32Ty; 6220 else 6221 LengthTy = IntPtrTy; 6222 } 6223 Fields.addInt(LengthTy, StringLength); 6224 6225 // Swift ABI requires 8-byte alignment to ensure that the _Atomic(uint64_t) is 6226 // properly aligned on 32-bit platforms. 6227 CharUnits Alignment = 6228 IsSwiftABI ? Context.toCharUnitsFromBits(64) : getPointerAlign(); 6229 6230 // The struct. 6231 GV = Fields.finishAndCreateGlobal("_unnamed_cfstring_", Alignment, 6232 /*isConstant=*/false, 6233 llvm::GlobalVariable::PrivateLinkage); 6234 GV->addAttribute("objc_arc_inert"); 6235 switch (Triple.getObjectFormat()) { 6236 case llvm::Triple::UnknownObjectFormat: 6237 llvm_unreachable("unknown file format"); 6238 case llvm::Triple::DXContainer: 6239 case llvm::Triple::GOFF: 6240 case llvm::Triple::SPIRV: 6241 case llvm::Triple::XCOFF: 6242 llvm_unreachable("unimplemented"); 6243 case llvm::Triple::COFF: 6244 case llvm::Triple::ELF: 6245 case llvm::Triple::Wasm: 6246 GV->setSection("cfstring"); 6247 break; 6248 case llvm::Triple::MachO: 6249 GV->setSection("__DATA,__cfstring"); 6250 break; 6251 } 6252 Entry.second = GV; 6253 6254 return ConstantAddress(GV, GV->getValueType(), Alignment); 6255 } 6256 6257 bool CodeGenModule::getExpressionLocationsEnabled() const { 6258 return !CodeGenOpts.EmitCodeView || CodeGenOpts.DebugColumnInfo; 6259 } 6260 6261 QualType CodeGenModule::getObjCFastEnumerationStateType() { 6262 if (ObjCFastEnumerationStateType.isNull()) { 6263 RecordDecl *D = Context.buildImplicitRecord("__objcFastEnumerationState"); 6264 D->startDefinition(); 6265 6266 QualType FieldTypes[] = { 6267 Context.UnsignedLongTy, Context.getPointerType(Context.getObjCIdType()), 6268 Context.getPointerType(Context.UnsignedLongTy), 6269 Context.getConstantArrayType(Context.UnsignedLongTy, llvm::APInt(32, 5), 6270 nullptr, ArraySizeModifier::Normal, 0)}; 6271 6272 for (size_t i = 0; i < 4; ++i) { 6273 FieldDecl *Field = FieldDecl::Create(Context, 6274 D, 6275 SourceLocation(), 6276 SourceLocation(), nullptr, 6277 FieldTypes[i], /*TInfo=*/nullptr, 6278 /*BitWidth=*/nullptr, 6279 /*Mutable=*/false, 6280 ICIS_NoInit); 6281 Field->setAccess(AS_public); 6282 D->addDecl(Field); 6283 } 6284 6285 D->completeDefinition(); 6286 ObjCFastEnumerationStateType = Context.getTagDeclType(D); 6287 } 6288 6289 return ObjCFastEnumerationStateType; 6290 } 6291 6292 llvm::Constant * 6293 CodeGenModule::GetConstantArrayFromStringLiteral(const StringLiteral *E) { 6294 assert(!E->getType()->isPointerType() && "Strings are always arrays"); 6295 6296 // Don't emit it as the address of the string, emit the string data itself 6297 // as an inline array. 6298 if (E->getCharByteWidth() == 1) { 6299 SmallString<64> Str(E->getString()); 6300 6301 // Resize the string to the right size, which is indicated by its type. 6302 const ConstantArrayType *CAT = Context.getAsConstantArrayType(E->getType()); 6303 assert(CAT && "String literal not of constant array type!"); 6304 Str.resize(CAT->getZExtSize()); 6305 return llvm::ConstantDataArray::getString(VMContext, Str, false); 6306 } 6307 6308 auto *AType = cast<llvm::ArrayType>(getTypes().ConvertType(E->getType())); 6309 llvm::Type *ElemTy = AType->getElementType(); 6310 unsigned NumElements = AType->getNumElements(); 6311 6312 // Wide strings have either 2-byte or 4-byte elements. 6313 if (ElemTy->getPrimitiveSizeInBits() == 16) { 6314 SmallVector<uint16_t, 32> Elements; 6315 Elements.reserve(NumElements); 6316 6317 for(unsigned i = 0, e = E->getLength(); i != e; ++i) 6318 Elements.push_back(E->getCodeUnit(i)); 6319 Elements.resize(NumElements); 6320 return llvm::ConstantDataArray::get(VMContext, Elements); 6321 } 6322 6323 assert(ElemTy->getPrimitiveSizeInBits() == 32); 6324 SmallVector<uint32_t, 32> Elements; 6325 Elements.reserve(NumElements); 6326 6327 for(unsigned i = 0, e = E->getLength(); i != e; ++i) 6328 Elements.push_back(E->getCodeUnit(i)); 6329 Elements.resize(NumElements); 6330 return llvm::ConstantDataArray::get(VMContext, Elements); 6331 } 6332 6333 static llvm::GlobalVariable * 6334 GenerateStringLiteral(llvm::Constant *C, llvm::GlobalValue::LinkageTypes LT, 6335 CodeGenModule &CGM, StringRef GlobalName, 6336 CharUnits Alignment) { 6337 unsigned AddrSpace = CGM.getContext().getTargetAddressSpace( 6338 CGM.GetGlobalConstantAddressSpace()); 6339 6340 llvm::Module &M = CGM.getModule(); 6341 // Create a global variable for this string 6342 auto *GV = new llvm::GlobalVariable( 6343 M, C->getType(), !CGM.getLangOpts().WritableStrings, LT, C, GlobalName, 6344 nullptr, llvm::GlobalVariable::NotThreadLocal, AddrSpace); 6345 GV->setAlignment(Alignment.getAsAlign()); 6346 GV->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); 6347 if (GV->isWeakForLinker()) { 6348 assert(CGM.supportsCOMDAT() && "Only COFF uses weak string literals"); 6349 GV->setComdat(M.getOrInsertComdat(GV->getName())); 6350 } 6351 CGM.setDSOLocal(GV); 6352 6353 return GV; 6354 } 6355 6356 /// GetAddrOfConstantStringFromLiteral - Return a pointer to a 6357 /// constant array for the given string literal. 6358 ConstantAddress 6359 CodeGenModule::GetAddrOfConstantStringFromLiteral(const StringLiteral *S, 6360 StringRef Name) { 6361 CharUnits Alignment = 6362 getContext().getAlignOfGlobalVarInChars(S->getType(), /*VD=*/nullptr); 6363 6364 llvm::Constant *C = GetConstantArrayFromStringLiteral(S); 6365 llvm::GlobalVariable **Entry = nullptr; 6366 if (!LangOpts.WritableStrings) { 6367 Entry = &ConstantStringMap[C]; 6368 if (auto GV = *Entry) { 6369 if (uint64_t(Alignment.getQuantity()) > GV->getAlignment()) 6370 GV->setAlignment(Alignment.getAsAlign()); 6371 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6372 GV->getValueType(), Alignment); 6373 } 6374 } 6375 6376 SmallString<256> MangledNameBuffer; 6377 StringRef GlobalVariableName; 6378 llvm::GlobalValue::LinkageTypes LT; 6379 6380 // Mangle the string literal if that's how the ABI merges duplicate strings. 6381 // Don't do it if they are writable, since we don't want writes in one TU to 6382 // affect strings in another. 6383 if (getCXXABI().getMangleContext().shouldMangleStringLiteral(S) && 6384 !LangOpts.WritableStrings) { 6385 llvm::raw_svector_ostream Out(MangledNameBuffer); 6386 getCXXABI().getMangleContext().mangleStringLiteral(S, Out); 6387 LT = llvm::GlobalValue::LinkOnceODRLinkage; 6388 GlobalVariableName = MangledNameBuffer; 6389 } else { 6390 LT = llvm::GlobalValue::PrivateLinkage; 6391 GlobalVariableName = Name; 6392 } 6393 6394 auto GV = GenerateStringLiteral(C, LT, *this, GlobalVariableName, Alignment); 6395 6396 CGDebugInfo *DI = getModuleDebugInfo(); 6397 if (DI && getCodeGenOpts().hasReducedDebugInfo()) 6398 DI->AddStringLiteralDebugInfo(GV, S); 6399 6400 if (Entry) 6401 *Entry = GV; 6402 6403 SanitizerMD->reportGlobal(GV, S->getStrTokenLoc(0), "<string literal>"); 6404 6405 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6406 GV->getValueType(), Alignment); 6407 } 6408 6409 /// GetAddrOfConstantStringFromObjCEncode - Return a pointer to a constant 6410 /// array for the given ObjCEncodeExpr node. 6411 ConstantAddress 6412 CodeGenModule::GetAddrOfConstantStringFromObjCEncode(const ObjCEncodeExpr *E) { 6413 std::string Str; 6414 getContext().getObjCEncodingForType(E->getEncodedType(), Str); 6415 6416 return GetAddrOfConstantCString(Str); 6417 } 6418 6419 /// GetAddrOfConstantCString - Returns a pointer to a character array containing 6420 /// the literal and a terminating '\0' character. 6421 /// The result has pointer to array type. 6422 ConstantAddress CodeGenModule::GetAddrOfConstantCString( 6423 const std::string &Str, const char *GlobalName) { 6424 StringRef StrWithNull(Str.c_str(), Str.size() + 1); 6425 CharUnits Alignment = getContext().getAlignOfGlobalVarInChars( 6426 getContext().CharTy, /*VD=*/nullptr); 6427 6428 llvm::Constant *C = 6429 llvm::ConstantDataArray::getString(getLLVMContext(), StrWithNull, false); 6430 6431 // Don't share any string literals if strings aren't constant. 6432 llvm::GlobalVariable **Entry = nullptr; 6433 if (!LangOpts.WritableStrings) { 6434 Entry = &ConstantStringMap[C]; 6435 if (auto GV = *Entry) { 6436 if (uint64_t(Alignment.getQuantity()) > GV->getAlignment()) 6437 GV->setAlignment(Alignment.getAsAlign()); 6438 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6439 GV->getValueType(), Alignment); 6440 } 6441 } 6442 6443 // Get the default prefix if a name wasn't specified. 6444 if (!GlobalName) 6445 GlobalName = ".str"; 6446 // Create a global variable for this. 6447 auto GV = GenerateStringLiteral(C, llvm::GlobalValue::PrivateLinkage, *this, 6448 GlobalName, Alignment); 6449 if (Entry) 6450 *Entry = GV; 6451 6452 return ConstantAddress(castStringLiteralToDefaultAddressSpace(*this, GV), 6453 GV->getValueType(), Alignment); 6454 } 6455 6456 ConstantAddress CodeGenModule::GetAddrOfGlobalTemporary( 6457 const MaterializeTemporaryExpr *E, const Expr *Init) { 6458 assert((E->getStorageDuration() == SD_Static || 6459 E->getStorageDuration() == SD_Thread) && "not a global temporary"); 6460 const auto *VD = cast<VarDecl>(E->getExtendingDecl()); 6461 6462 // If we're not materializing a subobject of the temporary, keep the 6463 // cv-qualifiers from the type of the MaterializeTemporaryExpr. 6464 QualType MaterializedType = Init->getType(); 6465 if (Init == E->getSubExpr()) 6466 MaterializedType = E->getType(); 6467 6468 CharUnits Align = getContext().getTypeAlignInChars(MaterializedType); 6469 6470 auto InsertResult = MaterializedGlobalTemporaryMap.insert({E, nullptr}); 6471 if (!InsertResult.second) { 6472 // We've seen this before: either we already created it or we're in the 6473 // process of doing so. 6474 if (!InsertResult.first->second) { 6475 // We recursively re-entered this function, probably during emission of 6476 // the initializer. Create a placeholder. We'll clean this up in the 6477 // outer call, at the end of this function. 6478 llvm::Type *Type = getTypes().ConvertTypeForMem(MaterializedType); 6479 InsertResult.first->second = new llvm::GlobalVariable( 6480 getModule(), Type, false, llvm::GlobalVariable::InternalLinkage, 6481 nullptr); 6482 } 6483 return ConstantAddress(InsertResult.first->second, 6484 llvm::cast<llvm::GlobalVariable>( 6485 InsertResult.first->second->stripPointerCasts()) 6486 ->getValueType(), 6487 Align); 6488 } 6489 6490 // FIXME: If an externally-visible declaration extends multiple temporaries, 6491 // we need to give each temporary the same name in every translation unit (and 6492 // we also need to make the temporaries externally-visible). 6493 SmallString<256> Name; 6494 llvm::raw_svector_ostream Out(Name); 6495 getCXXABI().getMangleContext().mangleReferenceTemporary( 6496 VD, E->getManglingNumber(), Out); 6497 6498 APValue *Value = nullptr; 6499 if (E->getStorageDuration() == SD_Static && VD->evaluateValue()) { 6500 // If the initializer of the extending declaration is a constant 6501 // initializer, we should have a cached constant initializer for this 6502 // temporary. Note that this might have a different value from the value 6503 // computed by evaluating the initializer if the surrounding constant 6504 // expression modifies the temporary. 6505 Value = E->getOrCreateValue(false); 6506 } 6507 6508 // Try evaluating it now, it might have a constant initializer. 6509 Expr::EvalResult EvalResult; 6510 if (!Value && Init->EvaluateAsRValue(EvalResult, getContext()) && 6511 !EvalResult.hasSideEffects()) 6512 Value = &EvalResult.Val; 6513 6514 LangAS AddrSpace = GetGlobalVarAddressSpace(VD); 6515 6516 std::optional<ConstantEmitter> emitter; 6517 llvm::Constant *InitialValue = nullptr; 6518 bool Constant = false; 6519 llvm::Type *Type; 6520 if (Value) { 6521 // The temporary has a constant initializer, use it. 6522 emitter.emplace(*this); 6523 InitialValue = emitter->emitForInitializer(*Value, AddrSpace, 6524 MaterializedType); 6525 Constant = 6526 MaterializedType.isConstantStorage(getContext(), /*ExcludeCtor*/ Value, 6527 /*ExcludeDtor*/ false); 6528 Type = InitialValue->getType(); 6529 } else { 6530 // No initializer, the initialization will be provided when we 6531 // initialize the declaration which performed lifetime extension. 6532 Type = getTypes().ConvertTypeForMem(MaterializedType); 6533 } 6534 6535 // Create a global variable for this lifetime-extended temporary. 6536 llvm::GlobalValue::LinkageTypes Linkage = getLLVMLinkageVarDefinition(VD); 6537 if (Linkage == llvm::GlobalVariable::ExternalLinkage) { 6538 const VarDecl *InitVD; 6539 if (VD->isStaticDataMember() && VD->getAnyInitializer(InitVD) && 6540 isa<CXXRecordDecl>(InitVD->getLexicalDeclContext())) { 6541 // Temporaries defined inside a class get linkonce_odr linkage because the 6542 // class can be defined in multiple translation units. 6543 Linkage = llvm::GlobalVariable::LinkOnceODRLinkage; 6544 } else { 6545 // There is no need for this temporary to have external linkage if the 6546 // VarDecl has external linkage. 6547 Linkage = llvm::GlobalVariable::InternalLinkage; 6548 } 6549 } 6550 auto TargetAS = getContext().getTargetAddressSpace(AddrSpace); 6551 auto *GV = new llvm::GlobalVariable( 6552 getModule(), Type, Constant, Linkage, InitialValue, Name.c_str(), 6553 /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal, TargetAS); 6554 if (emitter) emitter->finalize(GV); 6555 // Don't assign dllimport or dllexport to local linkage globals. 6556 if (!llvm::GlobalValue::isLocalLinkage(Linkage)) { 6557 setGVProperties(GV, VD); 6558 if (GV->getDLLStorageClass() == llvm::GlobalVariable::DLLExportStorageClass) 6559 // The reference temporary should never be dllexport. 6560 GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass); 6561 } 6562 GV->setAlignment(Align.getAsAlign()); 6563 if (supportsCOMDAT() && GV->isWeakForLinker()) 6564 GV->setComdat(TheModule.getOrInsertComdat(GV->getName())); 6565 if (VD->getTLSKind()) 6566 setTLSMode(GV, *VD); 6567 llvm::Constant *CV = GV; 6568 if (AddrSpace != LangAS::Default) 6569 CV = getTargetCodeGenInfo().performAddrSpaceCast( 6570 *this, GV, AddrSpace, LangAS::Default, 6571 llvm::PointerType::get( 6572 getLLVMContext(), 6573 getContext().getTargetAddressSpace(LangAS::Default))); 6574 6575 // Update the map with the new temporary. If we created a placeholder above, 6576 // replace it with the new global now. 6577 llvm::Constant *&Entry = MaterializedGlobalTemporaryMap[E]; 6578 if (Entry) { 6579 Entry->replaceAllUsesWith(CV); 6580 llvm::cast<llvm::GlobalVariable>(Entry)->eraseFromParent(); 6581 } 6582 Entry = CV; 6583 6584 return ConstantAddress(CV, Type, Align); 6585 } 6586 6587 /// EmitObjCPropertyImplementations - Emit information for synthesized 6588 /// properties for an implementation. 6589 void CodeGenModule::EmitObjCPropertyImplementations(const 6590 ObjCImplementationDecl *D) { 6591 for (const auto *PID : D->property_impls()) { 6592 // Dynamic is just for type-checking. 6593 if (PID->getPropertyImplementation() == ObjCPropertyImplDecl::Synthesize) { 6594 ObjCPropertyDecl *PD = PID->getPropertyDecl(); 6595 6596 // Determine which methods need to be implemented, some may have 6597 // been overridden. Note that ::isPropertyAccessor is not the method 6598 // we want, that just indicates if the decl came from a 6599 // property. What we want to know is if the method is defined in 6600 // this implementation. 6601 auto *Getter = PID->getGetterMethodDecl(); 6602 if (!Getter || Getter->isSynthesizedAccessorStub()) 6603 CodeGenFunction(*this).GenerateObjCGetter( 6604 const_cast<ObjCImplementationDecl *>(D), PID); 6605 auto *Setter = PID->getSetterMethodDecl(); 6606 if (!PD->isReadOnly() && (!Setter || Setter->isSynthesizedAccessorStub())) 6607 CodeGenFunction(*this).GenerateObjCSetter( 6608 const_cast<ObjCImplementationDecl *>(D), PID); 6609 } 6610 } 6611 } 6612 6613 static bool needsDestructMethod(ObjCImplementationDecl *impl) { 6614 const ObjCInterfaceDecl *iface = impl->getClassInterface(); 6615 for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin(); 6616 ivar; ivar = ivar->getNextIvar()) 6617 if (ivar->getType().isDestructedType()) 6618 return true; 6619 6620 return false; 6621 } 6622 6623 static bool AllTrivialInitializers(CodeGenModule &CGM, 6624 ObjCImplementationDecl *D) { 6625 CodeGenFunction CGF(CGM); 6626 for (ObjCImplementationDecl::init_iterator B = D->init_begin(), 6627 E = D->init_end(); B != E; ++B) { 6628 CXXCtorInitializer *CtorInitExp = *B; 6629 Expr *Init = CtorInitExp->getInit(); 6630 if (!CGF.isTrivialInitializer(Init)) 6631 return false; 6632 } 6633 return true; 6634 } 6635 6636 /// EmitObjCIvarInitializations - Emit information for ivar initialization 6637 /// for an implementation. 6638 void CodeGenModule::EmitObjCIvarInitializations(ObjCImplementationDecl *D) { 6639 // We might need a .cxx_destruct even if we don't have any ivar initializers. 6640 if (needsDestructMethod(D)) { 6641 const IdentifierInfo *II = &getContext().Idents.get(".cxx_destruct"); 6642 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 6643 ObjCMethodDecl *DTORMethod = ObjCMethodDecl::Create( 6644 getContext(), D->getLocation(), D->getLocation(), cxxSelector, 6645 getContext().VoidTy, nullptr, D, 6646 /*isInstance=*/true, /*isVariadic=*/false, 6647 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false, 6648 /*isImplicitlyDeclared=*/true, 6649 /*isDefined=*/false, ObjCImplementationControl::Required); 6650 D->addInstanceMethod(DTORMethod); 6651 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, DTORMethod, false); 6652 D->setHasDestructors(true); 6653 } 6654 6655 // If the implementation doesn't have any ivar initializers, we don't need 6656 // a .cxx_construct. 6657 if (D->getNumIvarInitializers() == 0 || 6658 AllTrivialInitializers(*this, D)) 6659 return; 6660 6661 const IdentifierInfo *II = &getContext().Idents.get(".cxx_construct"); 6662 Selector cxxSelector = getContext().Selectors.getSelector(0, &II); 6663 // The constructor returns 'self'. 6664 ObjCMethodDecl *CTORMethod = ObjCMethodDecl::Create( 6665 getContext(), D->getLocation(), D->getLocation(), cxxSelector, 6666 getContext().getObjCIdType(), nullptr, D, /*isInstance=*/true, 6667 /*isVariadic=*/false, 6668 /*isPropertyAccessor=*/true, /*isSynthesizedAccessorStub=*/false, 6669 /*isImplicitlyDeclared=*/true, 6670 /*isDefined=*/false, ObjCImplementationControl::Required); 6671 D->addInstanceMethod(CTORMethod); 6672 CodeGenFunction(*this).GenerateObjCCtorDtorMethod(D, CTORMethod, true); 6673 D->setHasNonZeroConstructors(true); 6674 } 6675 6676 // EmitLinkageSpec - Emit all declarations in a linkage spec. 6677 void CodeGenModule::EmitLinkageSpec(const LinkageSpecDecl *LSD) { 6678 if (LSD->getLanguage() != LinkageSpecLanguageIDs::C && 6679 LSD->getLanguage() != LinkageSpecLanguageIDs::CXX) { 6680 ErrorUnsupported(LSD, "linkage spec"); 6681 return; 6682 } 6683 6684 EmitDeclContext(LSD); 6685 } 6686 6687 void CodeGenModule::EmitTopLevelStmt(const TopLevelStmtDecl *D) { 6688 // Device code should not be at top level. 6689 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) 6690 return; 6691 6692 std::unique_ptr<CodeGenFunction> &CurCGF = 6693 GlobalTopLevelStmtBlockInFlight.first; 6694 6695 // We emitted a top-level stmt but after it there is initialization. 6696 // Stop squashing the top-level stmts into a single function. 6697 if (CurCGF && CXXGlobalInits.back() != CurCGF->CurFn) { 6698 CurCGF->FinishFunction(D->getEndLoc()); 6699 CurCGF = nullptr; 6700 } 6701 6702 if (!CurCGF) { 6703 // void __stmts__N(void) 6704 // FIXME: Ask the ABI name mangler to pick a name. 6705 std::string Name = "__stmts__" + llvm::utostr(CXXGlobalInits.size()); 6706 FunctionArgList Args; 6707 QualType RetTy = getContext().VoidTy; 6708 const CGFunctionInfo &FnInfo = 6709 getTypes().arrangeBuiltinFunctionDeclaration(RetTy, Args); 6710 llvm::FunctionType *FnTy = getTypes().GetFunctionType(FnInfo); 6711 llvm::Function *Fn = llvm::Function::Create( 6712 FnTy, llvm::GlobalValue::InternalLinkage, Name, &getModule()); 6713 6714 CurCGF.reset(new CodeGenFunction(*this)); 6715 GlobalTopLevelStmtBlockInFlight.second = D; 6716 CurCGF->StartFunction(GlobalDecl(), RetTy, Fn, FnInfo, Args, 6717 D->getBeginLoc(), D->getBeginLoc()); 6718 CXXGlobalInits.push_back(Fn); 6719 } 6720 6721 CurCGF->EmitStmt(D->getStmt()); 6722 } 6723 6724 void CodeGenModule::EmitDeclContext(const DeclContext *DC) { 6725 for (auto *I : DC->decls()) { 6726 // Unlike other DeclContexts, the contents of an ObjCImplDecl at TU scope 6727 // are themselves considered "top-level", so EmitTopLevelDecl on an 6728 // ObjCImplDecl does not recursively visit them. We need to do that in 6729 // case they're nested inside another construct (LinkageSpecDecl / 6730 // ExportDecl) that does stop them from being considered "top-level". 6731 if (auto *OID = dyn_cast<ObjCImplDecl>(I)) { 6732 for (auto *M : OID->methods()) 6733 EmitTopLevelDecl(M); 6734 } 6735 6736 EmitTopLevelDecl(I); 6737 } 6738 } 6739 6740 /// EmitTopLevelDecl - Emit code for a single top level declaration. 6741 void CodeGenModule::EmitTopLevelDecl(Decl *D) { 6742 // Ignore dependent declarations. 6743 if (D->isTemplated()) 6744 return; 6745 6746 // Consteval function shouldn't be emitted. 6747 if (auto *FD = dyn_cast<FunctionDecl>(D); FD && FD->isImmediateFunction()) 6748 return; 6749 6750 switch (D->getKind()) { 6751 case Decl::CXXConversion: 6752 case Decl::CXXMethod: 6753 case Decl::Function: 6754 EmitGlobal(cast<FunctionDecl>(D)); 6755 // Always provide some coverage mapping 6756 // even for the functions that aren't emitted. 6757 AddDeferredUnusedCoverageMapping(D); 6758 break; 6759 6760 case Decl::CXXDeductionGuide: 6761 // Function-like, but does not result in code emission. 6762 break; 6763 6764 case Decl::Var: 6765 case Decl::Decomposition: 6766 case Decl::VarTemplateSpecialization: 6767 EmitGlobal(cast<VarDecl>(D)); 6768 if (auto *DD = dyn_cast<DecompositionDecl>(D)) 6769 for (auto *B : DD->bindings()) 6770 if (auto *HD = B->getHoldingVar()) 6771 EmitGlobal(HD); 6772 break; 6773 6774 // Indirect fields from global anonymous structs and unions can be 6775 // ignored; only the actual variable requires IR gen support. 6776 case Decl::IndirectField: 6777 break; 6778 6779 // C++ Decls 6780 case Decl::Namespace: 6781 EmitDeclContext(cast<NamespaceDecl>(D)); 6782 break; 6783 case Decl::ClassTemplateSpecialization: { 6784 const auto *Spec = cast<ClassTemplateSpecializationDecl>(D); 6785 if (CGDebugInfo *DI = getModuleDebugInfo()) 6786 if (Spec->getSpecializationKind() == 6787 TSK_ExplicitInstantiationDefinition && 6788 Spec->hasDefinition()) 6789 DI->completeTemplateDefinition(*Spec); 6790 } [[fallthrough]]; 6791 case Decl::CXXRecord: { 6792 CXXRecordDecl *CRD = cast<CXXRecordDecl>(D); 6793 if (CGDebugInfo *DI = getModuleDebugInfo()) { 6794 if (CRD->hasDefinition()) 6795 DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D))); 6796 if (auto *ES = D->getASTContext().getExternalSource()) 6797 if (ES->hasExternalDefinitions(D) == ExternalASTSource::EK_Never) 6798 DI->completeUnusedClass(*CRD); 6799 } 6800 // Emit any static data members, they may be definitions. 6801 for (auto *I : CRD->decls()) 6802 if (isa<VarDecl>(I) || isa<CXXRecordDecl>(I)) 6803 EmitTopLevelDecl(I); 6804 break; 6805 } 6806 // No code generation needed. 6807 case Decl::UsingShadow: 6808 case Decl::ClassTemplate: 6809 case Decl::VarTemplate: 6810 case Decl::Concept: 6811 case Decl::VarTemplatePartialSpecialization: 6812 case Decl::FunctionTemplate: 6813 case Decl::TypeAliasTemplate: 6814 case Decl::Block: 6815 case Decl::Empty: 6816 case Decl::Binding: 6817 break; 6818 case Decl::Using: // using X; [C++] 6819 if (CGDebugInfo *DI = getModuleDebugInfo()) 6820 DI->EmitUsingDecl(cast<UsingDecl>(*D)); 6821 break; 6822 case Decl::UsingEnum: // using enum X; [C++] 6823 if (CGDebugInfo *DI = getModuleDebugInfo()) 6824 DI->EmitUsingEnumDecl(cast<UsingEnumDecl>(*D)); 6825 break; 6826 case Decl::NamespaceAlias: 6827 if (CGDebugInfo *DI = getModuleDebugInfo()) 6828 DI->EmitNamespaceAlias(cast<NamespaceAliasDecl>(*D)); 6829 break; 6830 case Decl::UsingDirective: // using namespace X; [C++] 6831 if (CGDebugInfo *DI = getModuleDebugInfo()) 6832 DI->EmitUsingDirective(cast<UsingDirectiveDecl>(*D)); 6833 break; 6834 case Decl::CXXConstructor: 6835 getCXXABI().EmitCXXConstructors(cast<CXXConstructorDecl>(D)); 6836 break; 6837 case Decl::CXXDestructor: 6838 getCXXABI().EmitCXXDestructors(cast<CXXDestructorDecl>(D)); 6839 break; 6840 6841 case Decl::StaticAssert: 6842 // Nothing to do. 6843 break; 6844 6845 // Objective-C Decls 6846 6847 // Forward declarations, no (immediate) code generation. 6848 case Decl::ObjCInterface: 6849 case Decl::ObjCCategory: 6850 break; 6851 6852 case Decl::ObjCProtocol: { 6853 auto *Proto = cast<ObjCProtocolDecl>(D); 6854 if (Proto->isThisDeclarationADefinition()) 6855 ObjCRuntime->GenerateProtocol(Proto); 6856 break; 6857 } 6858 6859 case Decl::ObjCCategoryImpl: 6860 // Categories have properties but don't support synthesize so we 6861 // can ignore them here. 6862 ObjCRuntime->GenerateCategory(cast<ObjCCategoryImplDecl>(D)); 6863 break; 6864 6865 case Decl::ObjCImplementation: { 6866 auto *OMD = cast<ObjCImplementationDecl>(D); 6867 EmitObjCPropertyImplementations(OMD); 6868 EmitObjCIvarInitializations(OMD); 6869 ObjCRuntime->GenerateClass(OMD); 6870 // Emit global variable debug information. 6871 if (CGDebugInfo *DI = getModuleDebugInfo()) 6872 if (getCodeGenOpts().hasReducedDebugInfo()) 6873 DI->getOrCreateInterfaceType(getContext().getObjCInterfaceType( 6874 OMD->getClassInterface()), OMD->getLocation()); 6875 break; 6876 } 6877 case Decl::ObjCMethod: { 6878 auto *OMD = cast<ObjCMethodDecl>(D); 6879 // If this is not a prototype, emit the body. 6880 if (OMD->getBody()) 6881 CodeGenFunction(*this).GenerateObjCMethod(OMD); 6882 break; 6883 } 6884 case Decl::ObjCCompatibleAlias: 6885 ObjCRuntime->RegisterAlias(cast<ObjCCompatibleAliasDecl>(D)); 6886 break; 6887 6888 case Decl::PragmaComment: { 6889 const auto *PCD = cast<PragmaCommentDecl>(D); 6890 switch (PCD->getCommentKind()) { 6891 case PCK_Unknown: 6892 llvm_unreachable("unexpected pragma comment kind"); 6893 case PCK_Linker: 6894 AppendLinkerOptions(PCD->getArg()); 6895 break; 6896 case PCK_Lib: 6897 AddDependentLib(PCD->getArg()); 6898 break; 6899 case PCK_Compiler: 6900 case PCK_ExeStr: 6901 case PCK_User: 6902 break; // We ignore all of these. 6903 } 6904 break; 6905 } 6906 6907 case Decl::PragmaDetectMismatch: { 6908 const auto *PDMD = cast<PragmaDetectMismatchDecl>(D); 6909 AddDetectMismatch(PDMD->getName(), PDMD->getValue()); 6910 break; 6911 } 6912 6913 case Decl::LinkageSpec: 6914 EmitLinkageSpec(cast<LinkageSpecDecl>(D)); 6915 break; 6916 6917 case Decl::FileScopeAsm: { 6918 // File-scope asm is ignored during device-side CUDA compilation. 6919 if (LangOpts.CUDA && LangOpts.CUDAIsDevice) 6920 break; 6921 // File-scope asm is ignored during device-side OpenMP compilation. 6922 if (LangOpts.OpenMPIsTargetDevice) 6923 break; 6924 // File-scope asm is ignored during device-side SYCL compilation. 6925 if (LangOpts.SYCLIsDevice) 6926 break; 6927 auto *AD = cast<FileScopeAsmDecl>(D); 6928 getModule().appendModuleInlineAsm(AD->getAsmString()->getString()); 6929 break; 6930 } 6931 6932 case Decl::TopLevelStmt: 6933 EmitTopLevelStmt(cast<TopLevelStmtDecl>(D)); 6934 break; 6935 6936 case Decl::Import: { 6937 auto *Import = cast<ImportDecl>(D); 6938 6939 // If we've already imported this module, we're done. 6940 if (!ImportedModules.insert(Import->getImportedModule())) 6941 break; 6942 6943 // Emit debug information for direct imports. 6944 if (!Import->getImportedOwningModule()) { 6945 if (CGDebugInfo *DI = getModuleDebugInfo()) 6946 DI->EmitImportDecl(*Import); 6947 } 6948 6949 // For C++ standard modules we are done - we will call the module 6950 // initializer for imported modules, and that will likewise call those for 6951 // any imports it has. 6952 if (CXX20ModuleInits && Import->getImportedOwningModule() && 6953 !Import->getImportedOwningModule()->isModuleMapModule()) 6954 break; 6955 6956 // For clang C++ module map modules the initializers for sub-modules are 6957 // emitted here. 6958 6959 // Find all of the submodules and emit the module initializers. 6960 llvm::SmallPtrSet<clang::Module *, 16> Visited; 6961 SmallVector<clang::Module *, 16> Stack; 6962 Visited.insert(Import->getImportedModule()); 6963 Stack.push_back(Import->getImportedModule()); 6964 6965 while (!Stack.empty()) { 6966 clang::Module *Mod = Stack.pop_back_val(); 6967 if (!EmittedModuleInitializers.insert(Mod).second) 6968 continue; 6969 6970 for (auto *D : Context.getModuleInitializers(Mod)) 6971 EmitTopLevelDecl(D); 6972 6973 // Visit the submodules of this module. 6974 for (auto *Submodule : Mod->submodules()) { 6975 // Skip explicit children; they need to be explicitly imported to emit 6976 // the initializers. 6977 if (Submodule->IsExplicit) 6978 continue; 6979 6980 if (Visited.insert(Submodule).second) 6981 Stack.push_back(Submodule); 6982 } 6983 } 6984 break; 6985 } 6986 6987 case Decl::Export: 6988 EmitDeclContext(cast<ExportDecl>(D)); 6989 break; 6990 6991 case Decl::OMPThreadPrivate: 6992 EmitOMPThreadPrivateDecl(cast<OMPThreadPrivateDecl>(D)); 6993 break; 6994 6995 case Decl::OMPAllocate: 6996 EmitOMPAllocateDecl(cast<OMPAllocateDecl>(D)); 6997 break; 6998 6999 case Decl::OMPDeclareReduction: 7000 EmitOMPDeclareReduction(cast<OMPDeclareReductionDecl>(D)); 7001 break; 7002 7003 case Decl::OMPDeclareMapper: 7004 EmitOMPDeclareMapper(cast<OMPDeclareMapperDecl>(D)); 7005 break; 7006 7007 case Decl::OMPRequires: 7008 EmitOMPRequiresDecl(cast<OMPRequiresDecl>(D)); 7009 break; 7010 7011 case Decl::Typedef: 7012 case Decl::TypeAlias: // using foo = bar; [C++11] 7013 if (CGDebugInfo *DI = getModuleDebugInfo()) 7014 DI->EmitAndRetainType( 7015 getContext().getTypedefType(cast<TypedefNameDecl>(D))); 7016 break; 7017 7018 case Decl::Record: 7019 if (CGDebugInfo *DI = getModuleDebugInfo()) 7020 if (cast<RecordDecl>(D)->getDefinition()) 7021 DI->EmitAndRetainType(getContext().getRecordType(cast<RecordDecl>(D))); 7022 break; 7023 7024 case Decl::Enum: 7025 if (CGDebugInfo *DI = getModuleDebugInfo()) 7026 if (cast<EnumDecl>(D)->getDefinition()) 7027 DI->EmitAndRetainType(getContext().getEnumType(cast<EnumDecl>(D))); 7028 break; 7029 7030 case Decl::HLSLBuffer: 7031 getHLSLRuntime().addBuffer(cast<HLSLBufferDecl>(D)); 7032 break; 7033 7034 default: 7035 // Make sure we handled everything we should, every other kind is a 7036 // non-top-level decl. FIXME: Would be nice to have an isTopLevelDeclKind 7037 // function. Need to recode Decl::Kind to do that easily. 7038 assert(isa<TypeDecl>(D) && "Unsupported decl kind"); 7039 break; 7040 } 7041 } 7042 7043 void CodeGenModule::AddDeferredUnusedCoverageMapping(Decl *D) { 7044 // Do we need to generate coverage mapping? 7045 if (!CodeGenOpts.CoverageMapping) 7046 return; 7047 switch (D->getKind()) { 7048 case Decl::CXXConversion: 7049 case Decl::CXXMethod: 7050 case Decl::Function: 7051 case Decl::ObjCMethod: 7052 case Decl::CXXConstructor: 7053 case Decl::CXXDestructor: { 7054 if (!cast<FunctionDecl>(D)->doesThisDeclarationHaveABody()) 7055 break; 7056 SourceManager &SM = getContext().getSourceManager(); 7057 if (LimitedCoverage && SM.getMainFileID() != SM.getFileID(D->getBeginLoc())) 7058 break; 7059 DeferredEmptyCoverageMappingDecls.try_emplace(D, true); 7060 break; 7061 } 7062 default: 7063 break; 7064 }; 7065 } 7066 7067 void CodeGenModule::ClearUnusedCoverageMapping(const Decl *D) { 7068 // Do we need to generate coverage mapping? 7069 if (!CodeGenOpts.CoverageMapping) 7070 return; 7071 if (const auto *Fn = dyn_cast<FunctionDecl>(D)) { 7072 if (Fn->isTemplateInstantiation()) 7073 ClearUnusedCoverageMapping(Fn->getTemplateInstantiationPattern()); 7074 } 7075 DeferredEmptyCoverageMappingDecls.insert_or_assign(D, false); 7076 } 7077 7078 void CodeGenModule::EmitDeferredUnusedCoverageMappings() { 7079 // We call takeVector() here to avoid use-after-free. 7080 // FIXME: DeferredEmptyCoverageMappingDecls is getting mutated because 7081 // we deserialize function bodies to emit coverage info for them, and that 7082 // deserializes more declarations. How should we handle that case? 7083 for (const auto &Entry : DeferredEmptyCoverageMappingDecls.takeVector()) { 7084 if (!Entry.second) 7085 continue; 7086 const Decl *D = Entry.first; 7087 switch (D->getKind()) { 7088 case Decl::CXXConversion: 7089 case Decl::CXXMethod: 7090 case Decl::Function: 7091 case Decl::ObjCMethod: { 7092 CodeGenPGO PGO(*this); 7093 GlobalDecl GD(cast<FunctionDecl>(D)); 7094 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 7095 getFunctionLinkage(GD)); 7096 break; 7097 } 7098 case Decl::CXXConstructor: { 7099 CodeGenPGO PGO(*this); 7100 GlobalDecl GD(cast<CXXConstructorDecl>(D), Ctor_Base); 7101 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 7102 getFunctionLinkage(GD)); 7103 break; 7104 } 7105 case Decl::CXXDestructor: { 7106 CodeGenPGO PGO(*this); 7107 GlobalDecl GD(cast<CXXDestructorDecl>(D), Dtor_Base); 7108 PGO.emitEmptyCounterMapping(D, getMangledName(GD), 7109 getFunctionLinkage(GD)); 7110 break; 7111 } 7112 default: 7113 break; 7114 }; 7115 } 7116 } 7117 7118 void CodeGenModule::EmitMainVoidAlias() { 7119 // In order to transition away from "__original_main" gracefully, emit an 7120 // alias for "main" in the no-argument case so that libc can detect when 7121 // new-style no-argument main is in used. 7122 if (llvm::Function *F = getModule().getFunction("main")) { 7123 if (!F->isDeclaration() && F->arg_size() == 0 && !F->isVarArg() && 7124 F->getReturnType()->isIntegerTy(Context.getTargetInfo().getIntWidth())) { 7125 auto *GA = llvm::GlobalAlias::create("__main_void", F); 7126 GA->setVisibility(llvm::GlobalValue::HiddenVisibility); 7127 } 7128 } 7129 } 7130 7131 /// Turns the given pointer into a constant. 7132 static llvm::Constant *GetPointerConstant(llvm::LLVMContext &Context, 7133 const void *Ptr) { 7134 uintptr_t PtrInt = reinterpret_cast<uintptr_t>(Ptr); 7135 llvm::Type *i64 = llvm::Type::getInt64Ty(Context); 7136 return llvm::ConstantInt::get(i64, PtrInt); 7137 } 7138 7139 static void EmitGlobalDeclMetadata(CodeGenModule &CGM, 7140 llvm::NamedMDNode *&GlobalMetadata, 7141 GlobalDecl D, 7142 llvm::GlobalValue *Addr) { 7143 if (!GlobalMetadata) 7144 GlobalMetadata = 7145 CGM.getModule().getOrInsertNamedMetadata("clang.global.decl.ptrs"); 7146 7147 // TODO: should we report variant information for ctors/dtors? 7148 llvm::Metadata *Ops[] = {llvm::ConstantAsMetadata::get(Addr), 7149 llvm::ConstantAsMetadata::get(GetPointerConstant( 7150 CGM.getLLVMContext(), D.getDecl()))}; 7151 GlobalMetadata->addOperand(llvm::MDNode::get(CGM.getLLVMContext(), Ops)); 7152 } 7153 7154 bool CodeGenModule::CheckAndReplaceExternCIFuncs(llvm::GlobalValue *Elem, 7155 llvm::GlobalValue *CppFunc) { 7156 // Store the list of ifuncs we need to replace uses in. 7157 llvm::SmallVector<llvm::GlobalIFunc *> IFuncs; 7158 // List of ConstantExprs that we should be able to delete when we're done 7159 // here. 7160 llvm::SmallVector<llvm::ConstantExpr *> CEs; 7161 7162 // It isn't valid to replace the extern-C ifuncs if all we find is itself! 7163 if (Elem == CppFunc) 7164 return false; 7165 7166 // First make sure that all users of this are ifuncs (or ifuncs via a 7167 // bitcast), and collect the list of ifuncs and CEs so we can work on them 7168 // later. 7169 for (llvm::User *User : Elem->users()) { 7170 // Users can either be a bitcast ConstExpr that is used by the ifuncs, OR an 7171 // ifunc directly. In any other case, just give up, as we don't know what we 7172 // could break by changing those. 7173 if (auto *ConstExpr = dyn_cast<llvm::ConstantExpr>(User)) { 7174 if (ConstExpr->getOpcode() != llvm::Instruction::BitCast) 7175 return false; 7176 7177 for (llvm::User *CEUser : ConstExpr->users()) { 7178 if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(CEUser)) { 7179 IFuncs.push_back(IFunc); 7180 } else { 7181 return false; 7182 } 7183 } 7184 CEs.push_back(ConstExpr); 7185 } else if (auto *IFunc = dyn_cast<llvm::GlobalIFunc>(User)) { 7186 IFuncs.push_back(IFunc); 7187 } else { 7188 // This user is one we don't know how to handle, so fail redirection. This 7189 // will result in an ifunc retaining a resolver name that will ultimately 7190 // fail to be resolved to a defined function. 7191 return false; 7192 } 7193 } 7194 7195 // Now we know this is a valid case where we can do this alias replacement, we 7196 // need to remove all of the references to Elem (and the bitcasts!) so we can 7197 // delete it. 7198 for (llvm::GlobalIFunc *IFunc : IFuncs) 7199 IFunc->setResolver(nullptr); 7200 for (llvm::ConstantExpr *ConstExpr : CEs) 7201 ConstExpr->destroyConstant(); 7202 7203 // We should now be out of uses for the 'old' version of this function, so we 7204 // can erase it as well. 7205 Elem->eraseFromParent(); 7206 7207 for (llvm::GlobalIFunc *IFunc : IFuncs) { 7208 // The type of the resolver is always just a function-type that returns the 7209 // type of the IFunc, so create that here. If the type of the actual 7210 // resolver doesn't match, it just gets bitcast to the right thing. 7211 auto *ResolverTy = 7212 llvm::FunctionType::get(IFunc->getType(), /*isVarArg*/ false); 7213 llvm::Constant *Resolver = GetOrCreateLLVMFunction( 7214 CppFunc->getName(), ResolverTy, {}, /*ForVTable*/ false); 7215 IFunc->setResolver(Resolver); 7216 } 7217 return true; 7218 } 7219 7220 /// For each function which is declared within an extern "C" region and marked 7221 /// as 'used', but has internal linkage, create an alias from the unmangled 7222 /// name to the mangled name if possible. People expect to be able to refer 7223 /// to such functions with an unmangled name from inline assembly within the 7224 /// same translation unit. 7225 void CodeGenModule::EmitStaticExternCAliases() { 7226 if (!getTargetCodeGenInfo().shouldEmitStaticExternCAliases()) 7227 return; 7228 for (auto &I : StaticExternCValues) { 7229 const IdentifierInfo *Name = I.first; 7230 llvm::GlobalValue *Val = I.second; 7231 7232 // If Val is null, that implies there were multiple declarations that each 7233 // had a claim to the unmangled name. In this case, generation of the alias 7234 // is suppressed. See CodeGenModule::MaybeHandleStaticInExternC. 7235 if (!Val) 7236 break; 7237 7238 llvm::GlobalValue *ExistingElem = 7239 getModule().getNamedValue(Name->getName()); 7240 7241 // If there is either not something already by this name, or we were able to 7242 // replace all uses from IFuncs, create the alias. 7243 if (!ExistingElem || CheckAndReplaceExternCIFuncs(ExistingElem, Val)) 7244 addCompilerUsedGlobal(llvm::GlobalAlias::create(Name->getName(), Val)); 7245 } 7246 } 7247 7248 bool CodeGenModule::lookupRepresentativeDecl(StringRef MangledName, 7249 GlobalDecl &Result) const { 7250 auto Res = Manglings.find(MangledName); 7251 if (Res == Manglings.end()) 7252 return false; 7253 Result = Res->getValue(); 7254 return true; 7255 } 7256 7257 /// Emits metadata nodes associating all the global values in the 7258 /// current module with the Decls they came from. This is useful for 7259 /// projects using IR gen as a subroutine. 7260 /// 7261 /// Since there's currently no way to associate an MDNode directly 7262 /// with an llvm::GlobalValue, we create a global named metadata 7263 /// with the name 'clang.global.decl.ptrs'. 7264 void CodeGenModule::EmitDeclMetadata() { 7265 llvm::NamedMDNode *GlobalMetadata = nullptr; 7266 7267 for (auto &I : MangledDeclNames) { 7268 llvm::GlobalValue *Addr = getModule().getNamedValue(I.second); 7269 // Some mangled names don't necessarily have an associated GlobalValue 7270 // in this module, e.g. if we mangled it for DebugInfo. 7271 if (Addr) 7272 EmitGlobalDeclMetadata(*this, GlobalMetadata, I.first, Addr); 7273 } 7274 } 7275 7276 /// Emits metadata nodes for all the local variables in the current 7277 /// function. 7278 void CodeGenFunction::EmitDeclMetadata() { 7279 if (LocalDeclMap.empty()) return; 7280 7281 llvm::LLVMContext &Context = getLLVMContext(); 7282 7283 // Find the unique metadata ID for this name. 7284 unsigned DeclPtrKind = Context.getMDKindID("clang.decl.ptr"); 7285 7286 llvm::NamedMDNode *GlobalMetadata = nullptr; 7287 7288 for (auto &I : LocalDeclMap) { 7289 const Decl *D = I.first; 7290 llvm::Value *Addr = I.second.emitRawPointer(*this); 7291 if (auto *Alloca = dyn_cast<llvm::AllocaInst>(Addr)) { 7292 llvm::Value *DAddr = GetPointerConstant(getLLVMContext(), D); 7293 Alloca->setMetadata( 7294 DeclPtrKind, llvm::MDNode::get( 7295 Context, llvm::ValueAsMetadata::getConstant(DAddr))); 7296 } else if (auto *GV = dyn_cast<llvm::GlobalValue>(Addr)) { 7297 GlobalDecl GD = GlobalDecl(cast<VarDecl>(D)); 7298 EmitGlobalDeclMetadata(CGM, GlobalMetadata, GD, GV); 7299 } 7300 } 7301 } 7302 7303 void CodeGenModule::EmitVersionIdentMetadata() { 7304 llvm::NamedMDNode *IdentMetadata = 7305 TheModule.getOrInsertNamedMetadata("llvm.ident"); 7306 std::string Version = getClangFullVersion(); 7307 llvm::LLVMContext &Ctx = TheModule.getContext(); 7308 7309 llvm::Metadata *IdentNode[] = {llvm::MDString::get(Ctx, Version)}; 7310 IdentMetadata->addOperand(llvm::MDNode::get(Ctx, IdentNode)); 7311 } 7312 7313 void CodeGenModule::EmitCommandLineMetadata() { 7314 llvm::NamedMDNode *CommandLineMetadata = 7315 TheModule.getOrInsertNamedMetadata("llvm.commandline"); 7316 std::string CommandLine = getCodeGenOpts().RecordCommandLine; 7317 llvm::LLVMContext &Ctx = TheModule.getContext(); 7318 7319 llvm::Metadata *CommandLineNode[] = {llvm::MDString::get(Ctx, CommandLine)}; 7320 CommandLineMetadata->addOperand(llvm::MDNode::get(Ctx, CommandLineNode)); 7321 } 7322 7323 void CodeGenModule::EmitCoverageFile() { 7324 llvm::NamedMDNode *CUNode = TheModule.getNamedMetadata("llvm.dbg.cu"); 7325 if (!CUNode) 7326 return; 7327 7328 llvm::NamedMDNode *GCov = TheModule.getOrInsertNamedMetadata("llvm.gcov"); 7329 llvm::LLVMContext &Ctx = TheModule.getContext(); 7330 auto *CoverageDataFile = 7331 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageDataFile); 7332 auto *CoverageNotesFile = 7333 llvm::MDString::get(Ctx, getCodeGenOpts().CoverageNotesFile); 7334 for (int i = 0, e = CUNode->getNumOperands(); i != e; ++i) { 7335 llvm::MDNode *CU = CUNode->getOperand(i); 7336 llvm::Metadata *Elts[] = {CoverageNotesFile, CoverageDataFile, CU}; 7337 GCov->addOperand(llvm::MDNode::get(Ctx, Elts)); 7338 } 7339 } 7340 7341 llvm::Constant *CodeGenModule::GetAddrOfRTTIDescriptor(QualType Ty, 7342 bool ForEH) { 7343 // Return a bogus pointer if RTTI is disabled, unless it's for EH. 7344 // FIXME: should we even be calling this method if RTTI is disabled 7345 // and it's not for EH? 7346 if (!shouldEmitRTTI(ForEH)) 7347 return llvm::Constant::getNullValue(GlobalsInt8PtrTy); 7348 7349 if (ForEH && Ty->isObjCObjectPointerType() && 7350 LangOpts.ObjCRuntime.isGNUFamily()) 7351 return ObjCRuntime->GetEHType(Ty); 7352 7353 return getCXXABI().getAddrOfRTTIDescriptor(Ty); 7354 } 7355 7356 void CodeGenModule::EmitOMPThreadPrivateDecl(const OMPThreadPrivateDecl *D) { 7357 // Do not emit threadprivates in simd-only mode. 7358 if (LangOpts.OpenMP && LangOpts.OpenMPSimd) 7359 return; 7360 for (auto RefExpr : D->varlists()) { 7361 auto *VD = cast<VarDecl>(cast<DeclRefExpr>(RefExpr)->getDecl()); 7362 bool PerformInit = 7363 VD->getAnyInitializer() && 7364 !VD->getAnyInitializer()->isConstantInitializer(getContext(), 7365 /*ForRef=*/false); 7366 7367 Address Addr(GetAddrOfGlobalVar(VD), 7368 getTypes().ConvertTypeForMem(VD->getType()), 7369 getContext().getDeclAlign(VD)); 7370 if (auto InitFunction = getOpenMPRuntime().emitThreadPrivateVarDefinition( 7371 VD, Addr, RefExpr->getBeginLoc(), PerformInit)) 7372 CXXGlobalInits.push_back(InitFunction); 7373 } 7374 } 7375 7376 llvm::Metadata * 7377 CodeGenModule::CreateMetadataIdentifierImpl(QualType T, MetadataTypeMap &Map, 7378 StringRef Suffix) { 7379 if (auto *FnType = T->getAs<FunctionProtoType>()) 7380 T = getContext().getFunctionType( 7381 FnType->getReturnType(), FnType->getParamTypes(), 7382 FnType->getExtProtoInfo().withExceptionSpec(EST_None)); 7383 7384 llvm::Metadata *&InternalId = Map[T.getCanonicalType()]; 7385 if (InternalId) 7386 return InternalId; 7387 7388 if (isExternallyVisible(T->getLinkage())) { 7389 std::string OutName; 7390 llvm::raw_string_ostream Out(OutName); 7391 getCXXABI().getMangleContext().mangleCanonicalTypeName( 7392 T, Out, getCodeGenOpts().SanitizeCfiICallNormalizeIntegers); 7393 7394 if (getCodeGenOpts().SanitizeCfiICallNormalizeIntegers) 7395 Out << ".normalized"; 7396 7397 Out << Suffix; 7398 7399 InternalId = llvm::MDString::get(getLLVMContext(), Out.str()); 7400 } else { 7401 InternalId = llvm::MDNode::getDistinct(getLLVMContext(), 7402 llvm::ArrayRef<llvm::Metadata *>()); 7403 } 7404 7405 return InternalId; 7406 } 7407 7408 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierForType(QualType T) { 7409 return CreateMetadataIdentifierImpl(T, MetadataIdMap, ""); 7410 } 7411 7412 llvm::Metadata * 7413 CodeGenModule::CreateMetadataIdentifierForVirtualMemPtrType(QualType T) { 7414 return CreateMetadataIdentifierImpl(T, VirtualMetadataIdMap, ".virtual"); 7415 } 7416 7417 // Generalize pointer types to a void pointer with the qualifiers of the 7418 // originally pointed-to type, e.g. 'const char *' and 'char * const *' 7419 // generalize to 'const void *' while 'char *' and 'const char **' generalize to 7420 // 'void *'. 7421 static QualType GeneralizeType(ASTContext &Ctx, QualType Ty) { 7422 if (!Ty->isPointerType()) 7423 return Ty; 7424 7425 return Ctx.getPointerType( 7426 QualType(Ctx.VoidTy).withCVRQualifiers( 7427 Ty->getPointeeType().getCVRQualifiers())); 7428 } 7429 7430 // Apply type generalization to a FunctionType's return and argument types 7431 static QualType GeneralizeFunctionType(ASTContext &Ctx, QualType Ty) { 7432 if (auto *FnType = Ty->getAs<FunctionProtoType>()) { 7433 SmallVector<QualType, 8> GeneralizedParams; 7434 for (auto &Param : FnType->param_types()) 7435 GeneralizedParams.push_back(GeneralizeType(Ctx, Param)); 7436 7437 return Ctx.getFunctionType( 7438 GeneralizeType(Ctx, FnType->getReturnType()), 7439 GeneralizedParams, FnType->getExtProtoInfo()); 7440 } 7441 7442 if (auto *FnType = Ty->getAs<FunctionNoProtoType>()) 7443 return Ctx.getFunctionNoProtoType( 7444 GeneralizeType(Ctx, FnType->getReturnType())); 7445 7446 llvm_unreachable("Encountered unknown FunctionType"); 7447 } 7448 7449 llvm::Metadata *CodeGenModule::CreateMetadataIdentifierGeneralized(QualType T) { 7450 return CreateMetadataIdentifierImpl(GeneralizeFunctionType(getContext(), T), 7451 GeneralizedMetadataIdMap, ".generalized"); 7452 } 7453 7454 /// Returns whether this module needs the "all-vtables" type identifier. 7455 bool CodeGenModule::NeedAllVtablesTypeId() const { 7456 // Returns true if at least one of vtable-based CFI checkers is enabled and 7457 // is not in the trapping mode. 7458 return ((LangOpts.Sanitize.has(SanitizerKind::CFIVCall) && 7459 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIVCall)) || 7460 (LangOpts.Sanitize.has(SanitizerKind::CFINVCall) && 7461 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFINVCall)) || 7462 (LangOpts.Sanitize.has(SanitizerKind::CFIDerivedCast) && 7463 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIDerivedCast)) || 7464 (LangOpts.Sanitize.has(SanitizerKind::CFIUnrelatedCast) && 7465 !CodeGenOpts.SanitizeTrap.has(SanitizerKind::CFIUnrelatedCast))); 7466 } 7467 7468 void CodeGenModule::AddVTableTypeMetadata(llvm::GlobalVariable *VTable, 7469 CharUnits Offset, 7470 const CXXRecordDecl *RD) { 7471 llvm::Metadata *MD = 7472 CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0)); 7473 VTable->addTypeMetadata(Offset.getQuantity(), MD); 7474 7475 if (CodeGenOpts.SanitizeCfiCrossDso) 7476 if (auto CrossDsoTypeId = CreateCrossDsoCfiTypeId(MD)) 7477 VTable->addTypeMetadata(Offset.getQuantity(), 7478 llvm::ConstantAsMetadata::get(CrossDsoTypeId)); 7479 7480 if (NeedAllVtablesTypeId()) { 7481 llvm::Metadata *MD = llvm::MDString::get(getLLVMContext(), "all-vtables"); 7482 VTable->addTypeMetadata(Offset.getQuantity(), MD); 7483 } 7484 } 7485 7486 llvm::SanitizerStatReport &CodeGenModule::getSanStats() { 7487 if (!SanStats) 7488 SanStats = std::make_unique<llvm::SanitizerStatReport>(&getModule()); 7489 7490 return *SanStats; 7491 } 7492 7493 llvm::Value * 7494 CodeGenModule::createOpenCLIntToSamplerConversion(const Expr *E, 7495 CodeGenFunction &CGF) { 7496 llvm::Constant *C = ConstantEmitter(CGF).emitAbstract(E, E->getType()); 7497 auto *SamplerT = getOpenCLRuntime().getSamplerType(E->getType().getTypePtr()); 7498 auto *FTy = llvm::FunctionType::get(SamplerT, {C->getType()}, false); 7499 auto *Call = CGF.EmitRuntimeCall( 7500 CreateRuntimeFunction(FTy, "__translate_sampler_initializer"), {C}); 7501 return Call; 7502 } 7503 7504 CharUnits CodeGenModule::getNaturalPointeeTypeAlignment( 7505 QualType T, LValueBaseInfo *BaseInfo, TBAAAccessInfo *TBAAInfo) { 7506 return getNaturalTypeAlignment(T->getPointeeType(), BaseInfo, TBAAInfo, 7507 /* forPointeeType= */ true); 7508 } 7509 7510 CharUnits CodeGenModule::getNaturalTypeAlignment(QualType T, 7511 LValueBaseInfo *BaseInfo, 7512 TBAAAccessInfo *TBAAInfo, 7513 bool forPointeeType) { 7514 if (TBAAInfo) 7515 *TBAAInfo = getTBAAAccessInfo(T); 7516 7517 // FIXME: This duplicates logic in ASTContext::getTypeAlignIfKnown. But 7518 // that doesn't return the information we need to compute BaseInfo. 7519 7520 // Honor alignment typedef attributes even on incomplete types. 7521 // We also honor them straight for C++ class types, even as pointees; 7522 // there's an expressivity gap here. 7523 if (auto TT = T->getAs<TypedefType>()) { 7524 if (auto Align = TT->getDecl()->getMaxAlignment()) { 7525 if (BaseInfo) 7526 *BaseInfo = LValueBaseInfo(AlignmentSource::AttributedType); 7527 return getContext().toCharUnitsFromBits(Align); 7528 } 7529 } 7530 7531 bool AlignForArray = T->isArrayType(); 7532 7533 // Analyze the base element type, so we don't get confused by incomplete 7534 // array types. 7535 T = getContext().getBaseElementType(T); 7536 7537 if (T->isIncompleteType()) { 7538 // We could try to replicate the logic from 7539 // ASTContext::getTypeAlignIfKnown, but nothing uses the alignment if the 7540 // type is incomplete, so it's impossible to test. We could try to reuse 7541 // getTypeAlignIfKnown, but that doesn't return the information we need 7542 // to set BaseInfo. So just ignore the possibility that the alignment is 7543 // greater than one. 7544 if (BaseInfo) 7545 *BaseInfo = LValueBaseInfo(AlignmentSource::Type); 7546 return CharUnits::One(); 7547 } 7548 7549 if (BaseInfo) 7550 *BaseInfo = LValueBaseInfo(AlignmentSource::Type); 7551 7552 CharUnits Alignment; 7553 const CXXRecordDecl *RD; 7554 if (T.getQualifiers().hasUnaligned()) { 7555 Alignment = CharUnits::One(); 7556 } else if (forPointeeType && !AlignForArray && 7557 (RD = T->getAsCXXRecordDecl())) { 7558 // For C++ class pointees, we don't know whether we're pointing at a 7559 // base or a complete object, so we generally need to use the 7560 // non-virtual alignment. 7561 Alignment = getClassPointerAlignment(RD); 7562 } else { 7563 Alignment = getContext().getTypeAlignInChars(T); 7564 } 7565 7566 // Cap to the global maximum type alignment unless the alignment 7567 // was somehow explicit on the type. 7568 if (unsigned MaxAlign = getLangOpts().MaxTypeAlign) { 7569 if (Alignment.getQuantity() > MaxAlign && 7570 !getContext().isAlignmentRequired(T)) 7571 Alignment = CharUnits::fromQuantity(MaxAlign); 7572 } 7573 return Alignment; 7574 } 7575 7576 bool CodeGenModule::stopAutoInit() { 7577 unsigned StopAfter = getContext().getLangOpts().TrivialAutoVarInitStopAfter; 7578 if (StopAfter) { 7579 // This number is positive only when -ftrivial-auto-var-init-stop-after=* is 7580 // used 7581 if (NumAutoVarInit >= StopAfter) { 7582 return true; 7583 } 7584 if (!NumAutoVarInit) { 7585 unsigned DiagID = getDiags().getCustomDiagID( 7586 DiagnosticsEngine::Warning, 7587 "-ftrivial-auto-var-init-stop-after=%0 has been enabled to limit the " 7588 "number of times ftrivial-auto-var-init=%1 gets applied."); 7589 getDiags().Report(DiagID) 7590 << StopAfter 7591 << (getContext().getLangOpts().getTrivialAutoVarInit() == 7592 LangOptions::TrivialAutoVarInitKind::Zero 7593 ? "zero" 7594 : "pattern"); 7595 } 7596 ++NumAutoVarInit; 7597 } 7598 return false; 7599 } 7600 7601 void CodeGenModule::printPostfixForExternalizedDecl(llvm::raw_ostream &OS, 7602 const Decl *D) const { 7603 // ptxas does not allow '.' in symbol names. On the other hand, HIP prefers 7604 // postfix beginning with '.' since the symbol name can be demangled. 7605 if (LangOpts.HIP) 7606 OS << (isa<VarDecl>(D) ? ".static." : ".intern."); 7607 else 7608 OS << (isa<VarDecl>(D) ? "__static__" : "__intern__"); 7609 7610 // If the CUID is not specified we try to generate a unique postfix. 7611 if (getLangOpts().CUID.empty()) { 7612 SourceManager &SM = getContext().getSourceManager(); 7613 PresumedLoc PLoc = SM.getPresumedLoc(D->getLocation()); 7614 assert(PLoc.isValid() && "Source location is expected to be valid."); 7615 7616 // Get the hash of the user defined macros. 7617 llvm::MD5 Hash; 7618 llvm::MD5::MD5Result Result; 7619 for (const auto &Arg : PreprocessorOpts.Macros) 7620 Hash.update(Arg.first); 7621 Hash.final(Result); 7622 7623 // Get the UniqueID for the file containing the decl. 7624 llvm::sys::fs::UniqueID ID; 7625 if (llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID)) { 7626 PLoc = SM.getPresumedLoc(D->getLocation(), /*UseLineDirectives=*/false); 7627 assert(PLoc.isValid() && "Source location is expected to be valid."); 7628 if (auto EC = llvm::sys::fs::getUniqueID(PLoc.getFilename(), ID)) 7629 SM.getDiagnostics().Report(diag::err_cannot_open_file) 7630 << PLoc.getFilename() << EC.message(); 7631 } 7632 OS << llvm::format("%x", ID.getFile()) << llvm::format("%x", ID.getDevice()) 7633 << "_" << llvm::utohexstr(Result.low(), /*LowerCase=*/true, /*Width=*/8); 7634 } else { 7635 OS << getContext().getCUIDHash(); 7636 } 7637 } 7638 7639 void CodeGenModule::moveLazyEmissionStates(CodeGenModule *NewBuilder) { 7640 assert(DeferredDeclsToEmit.empty() && 7641 "Should have emitted all decls deferred to emit."); 7642 assert(NewBuilder->DeferredDecls.empty() && 7643 "Newly created module should not have deferred decls"); 7644 NewBuilder->DeferredDecls = std::move(DeferredDecls); 7645 assert(EmittedDeferredDecls.empty() && 7646 "Still have (unmerged) EmittedDeferredDecls deferred decls"); 7647 7648 assert(NewBuilder->DeferredVTables.empty() && 7649 "Newly created module should not have deferred vtables"); 7650 NewBuilder->DeferredVTables = std::move(DeferredVTables); 7651 7652 assert(NewBuilder->MangledDeclNames.empty() && 7653 "Newly created module should not have mangled decl names"); 7654 assert(NewBuilder->Manglings.empty() && 7655 "Newly created module should not have manglings"); 7656 NewBuilder->Manglings = std::move(Manglings); 7657 7658 NewBuilder->WeakRefReferences = std::move(WeakRefReferences); 7659 7660 NewBuilder->TBAA = std::move(TBAA); 7661 7662 NewBuilder->ABI->MangleCtx = std::move(ABI->MangleCtx); 7663 } 7664