clang/lib/CodeGen/BackendUtil.cpp

   1 //===--- BackendUtil.cpp - LLVM Backend Utilities -------------------------===//
   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 #include "clang/CodeGen/BackendUtil.h"
  10 #include "clang/Basic/CodeGenOptions.h"
  11 #include "clang/Basic/Diagnostic.h"
  12 #include "clang/Basic/LangOptions.h"
  13 #include "clang/Basic/TargetOptions.h"
  14 #include "clang/Frontend/FrontendDiagnostic.h"
  15 #include "clang/Frontend/Utils.h"
  16 #include "clang/Lex/HeaderSearchOptions.h"
  17 #include "llvm/ADT/SmallSet.h"
  18 #include "llvm/ADT/StringExtras.h"
  19 #include "llvm/ADT/StringSwitch.h"
  20 #include "llvm/Analysis/AliasAnalysis.h"
  21 #include "llvm/Analysis/GlobalsModRef.h"
  22 #include "llvm/Analysis/TargetLibraryInfo.h"
  23 #include "llvm/Analysis/TargetTransformInfo.h"
  24 #include "llvm/Bitcode/BitcodeReader.h"
  25 #include "llvm/Bitcode/BitcodeWriter.h"
  26 #include "llvm/Bitcode/BitcodeWriterPass.h"
  27 #include "llvm/CodeGen/RegAllocRegistry.h"
  28 #include "llvm/CodeGen/SchedulerRegistry.h"
  29 #include "llvm/CodeGen/TargetSubtargetInfo.h"
  30 #include "llvm/IR/DataLayout.h"
  31 #include "llvm/IR/DebugInfo.h"
  32 #include "llvm/IR/LegacyPassManager.h"
  33 #include "llvm/IR/Module.h"
  34 #include "llvm/IR/ModuleSummaryIndex.h"
  35 #include "llvm/IR/PassManager.h"
  36 #include "llvm/IR/Verifier.h"
  37 #include "llvm/IRPrinter/IRPrintingPasses.h"
  38 #include "llvm/LTO/LTOBackend.h"
  39 #include "llvm/MC/MCAsmInfo.h"
  40 #include "llvm/MC/SubtargetFeature.h"
  41 #include "llvm/MC/TargetRegistry.h"
  42 #include "llvm/Object/OffloadBinary.h"
  43 #include "llvm/Passes/PassBuilder.h"
  44 #include "llvm/Passes/PassPlugin.h"
  45 #include "llvm/Passes/StandardInstrumentations.h"
  46 #include "llvm/Support/BuryPointer.h"
  47 #include "llvm/Support/CommandLine.h"
  48 #include "llvm/Support/MemoryBuffer.h"
  49 #include "llvm/Support/PrettyStackTrace.h"
  50 #include "llvm/Support/TimeProfiler.h"
  51 #include "llvm/Support/Timer.h"
  52 #include "llvm/Support/ToolOutputFile.h"
  53 #include "llvm/Support/VirtualFileSystem.h"
  54 #include "llvm/Support/raw_ostream.h"
  55 #include "llvm/Target/TargetMachine.h"
  56 #include "llvm/Target/TargetOptions.h"
  57 #include "llvm/TargetParser/Triple.h"
  58 #include "llvm/Transforms/IPO/LowerTypeTests.h"
  59 #include "llvm/Transforms/IPO/ThinLTOBitcodeWriter.h"
  60 #include "llvm/Transforms/InstCombine/InstCombine.h"
  61 #include "llvm/Transforms/Instrumentation.h"
  62 #include "llvm/Transforms/Instrumentation/AddressSanitizer.h"
  63 #include "llvm/Transforms/Instrumentation/AddressSanitizerOptions.h"
  64 #include "llvm/Transforms/Instrumentation/BoundsChecking.h"
  65 #include "llvm/Transforms/Instrumentation/DataFlowSanitizer.h"
  66 #include "llvm/Transforms/Instrumentation/GCOVProfiler.h"
  67 #include "llvm/Transforms/Instrumentation/HWAddressSanitizer.h"
  68 #include "llvm/Transforms/Instrumentation/InstrProfiling.h"
  69 #include "llvm/Transforms/Instrumentation/KCFI.h"
  70 #include "llvm/Transforms/Instrumentation/MemProfiler.h"
  71 #include "llvm/Transforms/Instrumentation/MemorySanitizer.h"
  72 #include "llvm/Transforms/Instrumentation/SanitizerBinaryMetadata.h"
  73 #include "llvm/Transforms/Instrumentation/SanitizerCoverage.h"
  74 #include "llvm/Transforms/Instrumentation/ThreadSanitizer.h"
  75 #include "llvm/Transforms/ObjCARC.h"
  76 #include "llvm/Transforms/Scalar/EarlyCSE.h"
  77 #include "llvm/Transforms/Scalar/GVN.h"
  78 #include "llvm/Transforms/Scalar/JumpThreading.h"
  79 #include "llvm/Transforms/Utils/Debugify.h"
  80 #include "llvm/Transforms/Utils/EntryExitInstrumenter.h"
  81 #include "llvm/Transforms/Utils/ModuleUtils.h"
  82 #include <memory>
  83 #include <optional>
  84 using namespace clang;
  85 using namespace llvm;
  86
  87 #define HANDLE_EXTENSION(Ext)                                                  \
  88   llvm::PassPluginLibraryInfo get##Ext##PluginInfo();
  89 #include "llvm/Support/Extension.def"
  90
  91 namespace llvm {
  92 extern cl::opt<bool> DebugInfoCorrelate;
  93
  94 // Experiment to move sanitizers earlier.
  95 static cl::opt<bool> ClSanitizeOnOptimizerEarlyEP(
  96     "sanitizer-early-opt-ep", cl::Optional,
  97     cl::desc("Insert sanitizers on OptimizerEarlyEP."), cl::init(false));
  98 }
  99
 100 namespace {
 101
 102 // Default filename used for profile generation.
 103 std::string getDefaultProfileGenName() {
 104   return DebugInfoCorrelate ? "default_%p.proflite" : "default_%m.profraw";
 105 }
 106
 107 class EmitAssemblyHelper {
 108   DiagnosticsEngine &Diags;
 109   const HeaderSearchOptions &HSOpts;
 110   const CodeGenOptions &CodeGenOpts;
 111   const clang::TargetOptions &TargetOpts;
 112   const LangOptions &LangOpts;
 113   Module *TheModule;
 114   IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS;
 115
 116   Timer CodeGenerationTime;
 117
 118   std::unique_ptr<raw_pwrite_stream> OS;
 119
 120   Triple TargetTriple;
 121
 122   TargetIRAnalysis getTargetIRAnalysis() const {
 123     if (TM)
 124       return TM->getTargetIRAnalysis();
 125
 126     return TargetIRAnalysis();
 127   }
 128
 129   /// Generates the TargetMachine.
 130   /// Leaves TM unchanged if it is unable to create the target machine.
 131   /// Some of our clang tests specify triples which are not built
 132   /// into clang. This is okay because these tests check the generated
 133   /// IR, and they require DataLayout which depends on the triple.
 134   /// In this case, we allow this method to fail and not report an error.
 135   /// When MustCreateTM is used, we print an error if we are unable to load
 136   /// the requested target.
 137   void CreateTargetMachine(bool MustCreateTM);
 138
 139   /// Add passes necessary to emit assembly or LLVM IR.
 140   ///
 141   /// \return True on success.
 142   bool AddEmitPasses(legacy::PassManager &CodeGenPasses, BackendAction Action,
 143                      raw_pwrite_stream &OS, raw_pwrite_stream *DwoOS);
 144
 145   std::unique_ptr<llvm::ToolOutputFile> openOutputFile(StringRef Path) {
 146     std::error_code EC;
 147     auto F = std::make_unique<llvm::ToolOutputFile>(Path, EC,
 148                                                      llvm::sys::fs::OF_None);
 149     if (EC) {
 150       Diags.Report(diag::err_fe_unable_to_open_output) << Path << EC.message();
 151       F.reset();
 152     }
 153     return F;
 154   }
 155
 156   void
 157   RunOptimizationPipeline(BackendAction Action,
 158                           std::unique_ptr<raw_pwrite_stream> &OS,
 159                           std::unique_ptr<llvm::ToolOutputFile> &ThinLinkOS);
 160   void RunCodegenPipeline(BackendAction Action,
 161                           std::unique_ptr<raw_pwrite_stream> &OS,
 162                           std::unique_ptr<llvm::ToolOutputFile> &DwoOS);
 163
 164   /// Check whether we should emit a module summary for regular LTO.
 165   /// The module summary should be emitted by default for regular LTO
 166   /// except for ld64 targets.
 167   ///
 168   /// \return True if the module summary should be emitted.
 169   bool shouldEmitRegularLTOSummary() const {
 170     return CodeGenOpts.PrepareForLTO && !CodeGenOpts.DisableLLVMPasses &&
 171            TargetTriple.getVendor() != llvm::Triple::Apple;
 172   }
 173
 174 public:
 175   EmitAssemblyHelper(DiagnosticsEngine &_Diags,
 176                      const HeaderSearchOptions &HeaderSearchOpts,
 177                      const CodeGenOptions &CGOpts,
 178                      const clang::TargetOptions &TOpts,
 179                      const LangOptions &LOpts, Module *M,
 180                      IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS)
 181       : Diags(_Diags), HSOpts(HeaderSearchOpts), CodeGenOpts(CGOpts),
 182         TargetOpts(TOpts), LangOpts(LOpts), TheModule(M), VFS(std::move(VFS)),
 183         CodeGenerationTime("codegen", "Code Generation Time"),
 184         TargetTriple(TheModule->getTargetTriple()) {}
 185
 186   ~EmitAssemblyHelper() {
 187     if (CodeGenOpts.DisableFree)
 188       BuryPointer(std::move(TM));
 189   }
 190
 191   std::unique_ptr<TargetMachine> TM;
 192
 193   // Emit output using the new pass manager for the optimization pipeline.
 194   void EmitAssembly(BackendAction Action,
 195                     std::unique_ptr<raw_pwrite_stream> OS);
 196 };
 197 }
 198
 199 static SanitizerCoverageOptions
 200 getSancovOptsFromCGOpts(const CodeGenOptions &CGOpts) {
 201   SanitizerCoverageOptions Opts;
 202   Opts.CoverageType =
 203       static_cast<SanitizerCoverageOptions::Type>(CGOpts.SanitizeCoverageType);
 204   Opts.IndirectCalls = CGOpts.SanitizeCoverageIndirectCalls;
 205   Opts.TraceBB = CGOpts.SanitizeCoverageTraceBB;
 206   Opts.TraceCmp = CGOpts.SanitizeCoverageTraceCmp;
 207   Opts.TraceDiv = CGOpts.SanitizeCoverageTraceDiv;
 208   Opts.TraceGep = CGOpts.SanitizeCoverageTraceGep;
 209   Opts.Use8bitCounters = CGOpts.SanitizeCoverage8bitCounters;
 210   Opts.TracePC = CGOpts.SanitizeCoverageTracePC;
 211   Opts.TracePCGuard = CGOpts.SanitizeCoverageTracePCGuard;
 212   Opts.NoPrune = CGOpts.SanitizeCoverageNoPrune;
 213   Opts.Inline8bitCounters = CGOpts.SanitizeCoverageInline8bitCounters;
 214   Opts.InlineBoolFlag = CGOpts.SanitizeCoverageInlineBoolFlag;
 215   Opts.PCTable = CGOpts.SanitizeCoveragePCTable;
 216   Opts.StackDepth = CGOpts.SanitizeCoverageStackDepth;
 217   Opts.TraceLoads = CGOpts.SanitizeCoverageTraceLoads;
 218   Opts.TraceStores = CGOpts.SanitizeCoverageTraceStores;
 219   Opts.CollectControlFlow = CGOpts.SanitizeCoverageControlFlow;
 220   return Opts;
 221 }
 222
 223 static SanitizerBinaryMetadataOptions
 224 getSanitizerBinaryMetadataOptions(const CodeGenOptions &CGOpts) {
 225   SanitizerBinaryMetadataOptions Opts;
 226   Opts.Covered = CGOpts.SanitizeBinaryMetadataCovered;
 227   Opts.Atomics = CGOpts.SanitizeBinaryMetadataAtomics;
 228   Opts.UAR = CGOpts.SanitizeBinaryMetadataUAR;
 229   return Opts;
 230 }
 231
 232 // Check if ASan should use GC-friendly instrumentation for globals.
 233 // First of all, there is no point if -fdata-sections is off (expect for MachO,
 234 // where this is not a factor). Also, on ELF this feature requires an assembler
 235 // extension that only works with -integrated-as at the moment.
 236 static bool asanUseGlobalsGC(const Triple &T, const CodeGenOptions &CGOpts) {
 237   if (!CGOpts.SanitizeAddressGlobalsDeadStripping)
 238     return false;
 239   switch (T.getObjectFormat()) {
 240   case Triple::MachO:
 241   case Triple::COFF:
 242     return true;
 243   case Triple::ELF:
 244     return !CGOpts.DisableIntegratedAS;
 245   case Triple::GOFF:
 246     llvm::report_fatal_error("ASan not implemented for GOFF");
 247   case Triple::XCOFF:
 248     llvm::report_fatal_error("ASan not implemented for XCOFF.");
 249   case Triple::Wasm:
 250   case Triple::DXContainer:
 251   case Triple::SPIRV:
 252   case Triple::UnknownObjectFormat:
 253     break;
 254   }
 255   return false;
 256 }
 257
 258 static TargetLibraryInfoImpl *createTLII(llvm::Triple &TargetTriple,
 259                                          const CodeGenOptions &CodeGenOpts) {
 260   TargetLibraryInfoImpl *TLII = new TargetLibraryInfoImpl(TargetTriple);
 261
 262   switch (CodeGenOpts.getVecLib()) {
 263   case CodeGenOptions::Accelerate:
 264     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::Accelerate,
 265                                              TargetTriple);
 266     break;
 267   case CodeGenOptions::LIBMVEC:
 268     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::LIBMVEC_X86,
 269                                              TargetTriple);
 270     break;
 271   case CodeGenOptions::MASSV:
 272     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::MASSV,
 273                                              TargetTriple);
 274     break;
 275   case CodeGenOptions::SVML:
 276     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::SVML,
 277                                              TargetTriple);
 278     break;
 279   case CodeGenOptions::SLEEF:
 280     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::SLEEFGNUABI,
 281                                              TargetTriple);
 282     break;
 283   case CodeGenOptions::Darwin_libsystem_m:
 284     TLII->addVectorizableFunctionsFromVecLib(
 285         TargetLibraryInfoImpl::DarwinLibSystemM, TargetTriple);
 286     break;
 287   default:
 288     break;
 289   }
 290   return TLII;
 291 }
 292
 293 static std::optional<llvm::CodeModel::Model>
 294 getCodeModel(const CodeGenOptions &CodeGenOpts) {
 295   unsigned CodeModel = llvm::StringSwitch<unsigned>(CodeGenOpts.CodeModel)
 296                            .Case("tiny", llvm::CodeModel::Tiny)
 297                            .Case("small", llvm::CodeModel::Small)
 298                            .Case("kernel", llvm::CodeModel::Kernel)
 299                            .Case("medium", llvm::CodeModel::Medium)
 300                            .Case("large", llvm::CodeModel::Large)
 301                            .Case("default", ~1u)
 302                            .Default(~0u);
 303   assert(CodeModel != ~0u && "invalid code model!");
 304   if (CodeModel == ~1u)
 305     return std::nullopt;
 306   return static_cast<llvm::CodeModel::Model>(CodeModel);
 307 }
 308
 309 static CodeGenFileType getCodeGenFileType(BackendAction Action) {
 310   if (Action == Backend_EmitObj)
 311     return CGFT_ObjectFile;
 312   else if (Action == Backend_EmitMCNull)
 313     return CGFT_Null;
 314   else {
 315     assert(Action == Backend_EmitAssembly && "Invalid action!");
 316     return CGFT_AssemblyFile;
 317   }
 318 }
 319
 320 static bool actionRequiresCodeGen(BackendAction Action) {
 321   return Action != Backend_EmitNothing && Action != Backend_EmitBC &&
 322          Action != Backend_EmitLL;
 323 }
 324
 325 static bool initTargetOptions(DiagnosticsEngine &Diags,
 326                               llvm::TargetOptions &Options,
 327                               const CodeGenOptions &CodeGenOpts,
 328                               const clang::TargetOptions &TargetOpts,
 329                               const LangOptions &LangOpts,
 330                               const HeaderSearchOptions &HSOpts) {
 331   switch (LangOpts.getThreadModel()) {
 332   case LangOptions::ThreadModelKind::POSIX:
 333     Options.ThreadModel = llvm::ThreadModel::POSIX;
 334     break;
 335   case LangOptions::ThreadModelKind::Single:
 336     Options.ThreadModel = llvm::ThreadModel::Single;
 337     break;
 338   }
 339
 340   // Set float ABI type.
 341   assert((CodeGenOpts.FloatABI == "soft" || CodeGenOpts.FloatABI == "softfp" ||
 342           CodeGenOpts.FloatABI == "hard" || CodeGenOpts.FloatABI.empty()) &&
 343          "Invalid Floating Point ABI!");
 344   Options.FloatABIType =
 345       llvm::StringSwitch<llvm::FloatABI::ABIType>(CodeGenOpts.FloatABI)
 346           .Case("soft", llvm::FloatABI::Soft)
 347           .Case("softfp", llvm::FloatABI::Soft)
 348           .Case("hard", llvm::FloatABI::Hard)
 349           .Default(llvm::FloatABI::Default);
 350
 351   // Set FP fusion mode.
 352   switch (LangOpts.getDefaultFPContractMode()) {
 353   case LangOptions::FPM_Off:
 354     // Preserve any contraction performed by the front-end.  (Strict performs
 355     // splitting of the muladd intrinsic in the backend.)
 356     Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
 357     break;
 358   case LangOptions::FPM_On:
 359   case LangOptions::FPM_FastHonorPragmas:
 360     Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
 361     break;
 362   case LangOptions::FPM_Fast:
 363     Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
 364     break;
 365   }
 366
 367   Options.BinutilsVersion =
 368       llvm::TargetMachine::parseBinutilsVersion(CodeGenOpts.BinutilsVersion);
 369   Options.UseInitArray = CodeGenOpts.UseInitArray;
 370   Options.DisableIntegratedAS = CodeGenOpts.DisableIntegratedAS;
 371   Options.CompressDebugSections = CodeGenOpts.getCompressDebugSections();
 372   Options.RelaxELFRelocations = CodeGenOpts.RelaxELFRelocations;
 373
 374   // Set EABI version.
 375   Options.EABIVersion = TargetOpts.EABIVersion;
 376
 377   if (LangOpts.hasSjLjExceptions())
 378     Options.ExceptionModel = llvm::ExceptionHandling::SjLj;
 379   if (LangOpts.hasSEHExceptions())
 380     Options.ExceptionModel = llvm::ExceptionHandling::WinEH;
 381   if (LangOpts.hasDWARFExceptions())
 382     Options.ExceptionModel = llvm::ExceptionHandling::DwarfCFI;
 383   if (LangOpts.hasWasmExceptions())
 384     Options.ExceptionModel = llvm::ExceptionHandling::Wasm;
 385
 386   Options.NoInfsFPMath = LangOpts.NoHonorInfs;
 387   Options.NoNaNsFPMath = LangOpts.NoHonorNaNs;
 388   Options.NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS;
 389   Options.UnsafeFPMath = LangOpts.AllowFPReassoc && LangOpts.AllowRecip &&
 390                          LangOpts.NoSignedZero && LangOpts.ApproxFunc &&
 391                          (LangOpts.getDefaultFPContractMode() ==
 392                               LangOptions::FPModeKind::FPM_Fast ||
 393                           LangOpts.getDefaultFPContractMode() ==
 394                               LangOptions::FPModeKind::FPM_FastHonorPragmas);
 395   Options.ApproxFuncFPMath = LangOpts.ApproxFunc;
 396
 397   Options.BBSections =
 398       llvm::StringSwitch<llvm::BasicBlockSection>(CodeGenOpts.BBSections)
 399           .Case("all", llvm::BasicBlockSection::All)
 400           .Case("labels", llvm::BasicBlockSection::Labels)
 401           .StartsWith("list=", llvm::BasicBlockSection::List)
 402           .Case("none", llvm::BasicBlockSection::None)
 403           .Default(llvm::BasicBlockSection::None);
 404
 405   if (Options.BBSections == llvm::BasicBlockSection::List) {
 406     ErrorOr<std::unique_ptr<MemoryBuffer>> MBOrErr =
 407         MemoryBuffer::getFile(CodeGenOpts.BBSections.substr(5));
 408     if (!MBOrErr) {
 409       Diags.Report(diag::err_fe_unable_to_load_basic_block_sections_file)
 410           << MBOrErr.getError().message();
 411       return false;
 412     }
 413     Options.BBSectionsFuncListBuf = std::move(*MBOrErr);
 414   }
 415
 416   Options.EnableMachineFunctionSplitter = CodeGenOpts.SplitMachineFunctions;
 417   Options.FunctionSections = CodeGenOpts.FunctionSections;
 418   Options.DataSections = CodeGenOpts.DataSections;
 419   Options.IgnoreXCOFFVisibility = LangOpts.IgnoreXCOFFVisibility;
 420   Options.UniqueSectionNames = CodeGenOpts.UniqueSectionNames;
 421   Options.UniqueBasicBlockSectionNames =
 422       CodeGenOpts.UniqueBasicBlockSectionNames;
 423   Options.TLSSize = CodeGenOpts.TLSSize;
 424   Options.EmulatedTLS = CodeGenOpts.EmulatedTLS;
 425   Options.DebuggerTuning = CodeGenOpts.getDebuggerTuning();
 426   Options.EmitStackSizeSection = CodeGenOpts.StackSizeSection;
 427   Options.StackUsageOutput = CodeGenOpts.StackUsageOutput;
 428   Options.EmitAddrsig = CodeGenOpts.Addrsig;
 429   Options.ForceDwarfFrameSection = CodeGenOpts.ForceDwarfFrameSection;
 430   Options.EmitCallSiteInfo = CodeGenOpts.EmitCallSiteInfo;
 431   Options.EnableAIXExtendedAltivecABI = LangOpts.EnableAIXExtendedAltivecABI;
 432   Options.XRayFunctionIndex = CodeGenOpts.XRayFunctionIndex;
 433   Options.LoopAlignment = CodeGenOpts.LoopAlignment;
 434   Options.DebugStrictDwarf = CodeGenOpts.DebugStrictDwarf;
 435   Options.ObjectFilenameForDebug = CodeGenOpts.ObjectFilenameForDebug;
 436   Options.Hotpatch = CodeGenOpts.HotPatch;
 437   Options.JMCInstrument = CodeGenOpts.JMCInstrument;
 438   Options.XCOFFReadOnlyPointers = CodeGenOpts.XCOFFReadOnlyPointers;
 439
 440   switch (CodeGenOpts.getSwiftAsyncFramePointer()) {
 441   case CodeGenOptions::SwiftAsyncFramePointerKind::Auto:
 442     Options.SwiftAsyncFramePointer =
 443         SwiftAsyncFramePointerMode::DeploymentBased;
 444     break;
 445
 446   case CodeGenOptions::SwiftAsyncFramePointerKind::Always:
 447     Options.SwiftAsyncFramePointer = SwiftAsyncFramePointerMode::Always;
 448     break;
 449
 450   case CodeGenOptions::SwiftAsyncFramePointerKind::Never:
 451     Options.SwiftAsyncFramePointer = SwiftAsyncFramePointerMode::Never;
 452     break;
 453   }
 454
 455   Options.MCOptions.SplitDwarfFile = CodeGenOpts.SplitDwarfFile;
 456   Options.MCOptions.EmitDwarfUnwind = CodeGenOpts.getEmitDwarfUnwind();
 457   Options.MCOptions.EmitCompactUnwindNonCanonical =
 458       CodeGenOpts.EmitCompactUnwindNonCanonical;
 459   Options.MCOptions.MCRelaxAll = CodeGenOpts.RelaxAll;
 460   Options.MCOptions.MCSaveTempLabels = CodeGenOpts.SaveTempLabels;
 461   Options.MCOptions.MCUseDwarfDirectory =
 462       CodeGenOpts.NoDwarfDirectoryAsm
 463           ? llvm::MCTargetOptions::DisableDwarfDirectory
 464           : llvm::MCTargetOptions::EnableDwarfDirectory;
 465   Options.MCOptions.MCNoExecStack = CodeGenOpts.NoExecStack;
 466   Options.MCOptions.MCIncrementalLinkerCompatible =
 467       CodeGenOpts.IncrementalLinkerCompatible;
 468   Options.MCOptions.MCFatalWarnings = CodeGenOpts.FatalWarnings;
 469   Options.MCOptions.MCNoWarn = CodeGenOpts.NoWarn;
 470   Options.MCOptions.AsmVerbose = CodeGenOpts.AsmVerbose;
 471   Options.MCOptions.Dwarf64 = CodeGenOpts.Dwarf64;
 472   Options.MCOptions.PreserveAsmComments = CodeGenOpts.PreserveAsmComments;
 473   Options.MCOptions.ABIName = TargetOpts.ABI;
 474   for (const auto &Entry : HSOpts.UserEntries)
 475     if (!Entry.IsFramework &&
 476         (Entry.Group == frontend::IncludeDirGroup::Quoted ||
 477          Entry.Group == frontend::IncludeDirGroup::Angled ||
 478          Entry.Group == frontend::IncludeDirGroup::System))
 479       Options.MCOptions.IASSearchPaths.push_back(
 480           Entry.IgnoreSysRoot ? Entry.Path : HSOpts.Sysroot + Entry.Path);
 481   Options.MCOptions.Argv0 = CodeGenOpts.Argv0;
 482   Options.MCOptions.CommandLineArgs = CodeGenOpts.CommandLineArgs;
 483   Options.MCOptions.AsSecureLogFile = CodeGenOpts.AsSecureLogFile;
 484   Options.MisExpect = CodeGenOpts.MisExpect;
 485
 486   return true;
 487 }
 488
 489 static std::optional<GCOVOptions>
 490 getGCOVOptions(const CodeGenOptions &CodeGenOpts, const LangOptions &LangOpts) {
 491   if (CodeGenOpts.CoverageNotesFile.empty() &&
 492       CodeGenOpts.CoverageDataFile.empty())
 493     return std::nullopt;
 494   // Not using 'GCOVOptions::getDefault' allows us to avoid exiting if
 495   // LLVM's -default-gcov-version flag is set to something invalid.
 496   GCOVOptions Options;
 497   Options.EmitNotes = !CodeGenOpts.CoverageNotesFile.empty();
 498   Options.EmitData = !CodeGenOpts.CoverageDataFile.empty();
 499   llvm::copy(CodeGenOpts.CoverageVersion, std::begin(Options.Version));
 500   Options.NoRedZone = CodeGenOpts.DisableRedZone;
 501   Options.Filter = CodeGenOpts.ProfileFilterFiles;
 502   Options.Exclude = CodeGenOpts.ProfileExcludeFiles;
 503   Options.Atomic = CodeGenOpts.AtomicProfileUpdate;
 504   return Options;
 505 }
 506
 507 static std::optional<InstrProfOptions>
 508 getInstrProfOptions(const CodeGenOptions &CodeGenOpts,
 509                     const LangOptions &LangOpts) {
 510   if (!CodeGenOpts.hasProfileClangInstr())
 511     return std::nullopt;
 512   InstrProfOptions Options;
 513   Options.NoRedZone = CodeGenOpts.DisableRedZone;
 514   Options.InstrProfileOutput = CodeGenOpts.InstrProfileOutput;
 515   Options.Atomic = CodeGenOpts.AtomicProfileUpdate;
 516   return Options;
 517 }
 518
 519 static void setCommandLineOpts(const CodeGenOptions &CodeGenOpts) {
 520   SmallVector<const char *, 16> BackendArgs;
 521   BackendArgs.push_back("clang"); // Fake program name.
 522   if (!CodeGenOpts.DebugPass.empty()) {
 523     BackendArgs.push_back("-debug-pass");
 524     BackendArgs.push_back(CodeGenOpts.DebugPass.c_str());
 525   }
 526   if (!CodeGenOpts.LimitFloatPrecision.empty()) {
 527     BackendArgs.push_back("-limit-float-precision");
 528     BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
 529   }
 530   // Check for the default "clang" invocation that won't set any cl::opt values.
 531   // Skip trying to parse the command line invocation to avoid the issues
 532   // described below.
 533   if (BackendArgs.size() == 1)
 534     return;
 535   BackendArgs.push_back(nullptr);
 536   // FIXME: The command line parser below is not thread-safe and shares a global
 537   // state, so this call might crash or overwrite the options of another Clang
 538   // instance in the same process.
 539   llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
 540                                     BackendArgs.data());
 541 }
 542
 543 void EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
 544   // Create the TargetMachine for generating code.
 545   std::string Error;
 546   std::string Triple = TheModule->getTargetTriple();
 547   const llvm::Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error);
 548   if (!TheTarget) {
 549     if (MustCreateTM)
 550       Diags.Report(diag::err_fe_unable_to_create_target) << Error;
 551     return;
 552   }
 553
 554   std::optional<llvm::CodeModel::Model> CM = getCodeModel(CodeGenOpts);
 555   std::string FeaturesStr =
 556       llvm::join(TargetOpts.Features.begin(), TargetOpts.Features.end(), ",");
 557   llvm::Reloc::Model RM = CodeGenOpts.RelocationModel;
 558   std::optional<CodeGenOpt::Level> OptLevelOrNone =
 559       CodeGenOpt::getLevel(CodeGenOpts.OptimizationLevel);
 560   assert(OptLevelOrNone && "Invalid optimization level!");
 561   CodeGenOpt::Level OptLevel = *OptLevelOrNone;
 562
 563   llvm::TargetOptions Options;
 564   if (!initTargetOptions(Diags, Options, CodeGenOpts, TargetOpts, LangOpts,
 565                          HSOpts))
 566     return;
 567   TM.reset(TheTarget->createTargetMachine(Triple, TargetOpts.CPU, FeaturesStr,
 568                                           Options, RM, CM, OptLevel));
 569 }
 570
 571 bool EmitAssemblyHelper::AddEmitPasses(legacy::PassManager &CodeGenPasses,
 572                                        BackendAction Action,
 573                                        raw_pwrite_stream &OS,
 574                                        raw_pwrite_stream *DwoOS) {
 575   // Add LibraryInfo.
 576   std::unique_ptr<TargetLibraryInfoImpl> TLII(
 577       createTLII(TargetTriple, CodeGenOpts));
 578   CodeGenPasses.add(new TargetLibraryInfoWrapperPass(*TLII));
 579
 580   // Normal mode, emit a .s or .o file by running the code generator. Note,
 581   // this also adds codegenerator level optimization passes.
 582   CodeGenFileType CGFT = getCodeGenFileType(Action);
 583
 584   // Add ObjC ARC final-cleanup optimizations. This is done as part of the
 585   // "codegen" passes so that it isn't run multiple times when there is
 586   // inlining happening.
 587   if (CodeGenOpts.OptimizationLevel > 0)
 588     CodeGenPasses.add(createObjCARCContractPass());
 589
 590   if (TM->addPassesToEmitFile(CodeGenPasses, OS, DwoOS, CGFT,
 591                               /*DisableVerify=*/!CodeGenOpts.VerifyModule)) {
 592     Diags.Report(diag::err_fe_unable_to_interface_with_target);
 593     return false;
 594   }
 595
 596   return true;
 597 }
 598
 599 static OptimizationLevel mapToLevel(const CodeGenOptions &Opts) {
 600   switch (Opts.OptimizationLevel) {
 601   default:
 602     llvm_unreachable("Invalid optimization level!");
 603
 604   case 0:
 605     return OptimizationLevel::O0;
 606
 607   case 1:
 608     return OptimizationLevel::O1;
 609
 610   case 2:
 611     switch (Opts.OptimizeSize) {
 612     default:
 613       llvm_unreachable("Invalid optimization level for size!");
 614
 615     case 0:
 616       return OptimizationLevel::O2;
 617
 618     case 1:
 619       return OptimizationLevel::Os;
 620
 621     case 2:
 622       return OptimizationLevel::Oz;
 623     }
 624
 625   case 3:
 626     return OptimizationLevel::O3;
 627   }
 628 }
 629
 630 static void addKCFIPass(const Triple &TargetTriple, const LangOptions &LangOpts,
 631                         PassBuilder &PB) {
 632   // If the back-end supports KCFI operand bundle lowering, skip KCFIPass.
 633   if (TargetTriple.getArch() == llvm::Triple::x86_64 ||
 634       TargetTriple.isAArch64(64))
 635     return;
 636
 637   // Ensure we lower KCFI operand bundles with -O0.
 638   PB.registerOptimizerLastEPCallback(
 639       [&](ModulePassManager &MPM, OptimizationLevel Level) {
 640         if (Level == OptimizationLevel::O0 &&
 641             LangOpts.Sanitize.has(SanitizerKind::KCFI))
 642           MPM.addPass(createModuleToFunctionPassAdaptor(KCFIPass()));
 643       });
 644
 645   // When optimizations are requested, run KCIFPass after InstCombine to
 646   // avoid unnecessary checks.
 647   PB.registerPeepholeEPCallback(
 648       [&](FunctionPassManager &FPM, OptimizationLevel Level) {
 649         if (Level != OptimizationLevel::O0 &&
 650             LangOpts.Sanitize.has(SanitizerKind::KCFI))
 651           FPM.addPass(KCFIPass());
 652       });
 653 }
 654
 655 static void addSanitizers(const Triple &TargetTriple,
 656                           const CodeGenOptions &CodeGenOpts,
 657                           const LangOptions &LangOpts, PassBuilder &PB) {
 658   auto SanitizersCallback = [&](ModulePassManager &MPM,
 659                                 OptimizationLevel Level) {
 660     if (CodeGenOpts.hasSanitizeCoverage()) {
 661       auto SancovOpts = getSancovOptsFromCGOpts(CodeGenOpts);
 662       MPM.addPass(SanitizerCoveragePass(
 663           SancovOpts, CodeGenOpts.SanitizeCoverageAllowlistFiles,
 664           CodeGenOpts.SanitizeCoverageIgnorelistFiles));
 665     }
 666
 667     if (CodeGenOpts.hasSanitizeBinaryMetadata()) {
 668       MPM.addPass(SanitizerBinaryMetadataPass(
 669           getSanitizerBinaryMetadataOptions(CodeGenOpts),
 670           CodeGenOpts.SanitizeMetadataIgnorelistFiles));
 671     }
 672
 673     auto MSanPass = [&](SanitizerMask Mask, bool CompileKernel) {
 674       if (LangOpts.Sanitize.has(Mask)) {
 675         int TrackOrigins = CodeGenOpts.SanitizeMemoryTrackOrigins;
 676         bool Recover = CodeGenOpts.SanitizeRecover.has(Mask);
 677
 678         MemorySanitizerOptions options(TrackOrigins, Recover, CompileKernel,
 679                                        CodeGenOpts.SanitizeMemoryParamRetval);
 680         MPM.addPass(MemorySanitizerPass(options));
 681         if (Level != OptimizationLevel::O0) {
 682           // MemorySanitizer inserts complex instrumentation that mostly follows
 683           // the logic of the original code, but operates on "shadow" values. It
 684           // can benefit from re-running some general purpose optimization
 685           // passes.
 686           MPM.addPass(RequireAnalysisPass<GlobalsAA, Module>());
 687           FunctionPassManager FPM;
 688           FPM.addPass(EarlyCSEPass(true /* Enable mem-ssa. */));
 689           FPM.addPass(InstCombinePass());
 690           FPM.addPass(JumpThreadingPass());
 691           FPM.addPass(GVNPass());
 692           FPM.addPass(InstCombinePass());
 693           MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
 694         }
 695       }
 696     };
 697     MSanPass(SanitizerKind::Memory, false);
 698     MSanPass(SanitizerKind::KernelMemory, true);
 699
 700     if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
 701       MPM.addPass(ModuleThreadSanitizerPass());
 702       MPM.addPass(createModuleToFunctionPassAdaptor(ThreadSanitizerPass()));
 703     }
 704
 705     auto ASanPass = [&](SanitizerMask Mask, bool CompileKernel) {
 706       if (LangOpts.Sanitize.has(Mask)) {
 707         bool UseGlobalGC = asanUseGlobalsGC(TargetTriple, CodeGenOpts);
 708         bool UseOdrIndicator = CodeGenOpts.SanitizeAddressUseOdrIndicator;
 709         llvm::AsanDtorKind DestructorKind =
 710             CodeGenOpts.getSanitizeAddressDtor();
 711         AddressSanitizerOptions Opts;
 712         Opts.CompileKernel = CompileKernel;
 713         Opts.Recover = CodeGenOpts.SanitizeRecover.has(Mask);
 714         Opts.UseAfterScope = CodeGenOpts.SanitizeAddressUseAfterScope;
 715         Opts.UseAfterReturn = CodeGenOpts.getSanitizeAddressUseAfterReturn();
 716         MPM.addPass(AddressSanitizerPass(Opts, UseGlobalGC, UseOdrIndicator,
 717                                          DestructorKind));
 718       }
 719     };
 720     ASanPass(SanitizerKind::Address, false);
 721     ASanPass(SanitizerKind::KernelAddress, true);
 722
 723     auto HWASanPass = [&](SanitizerMask Mask, bool CompileKernel) {
 724       if (LangOpts.Sanitize.has(Mask)) {
 725         bool Recover = CodeGenOpts.SanitizeRecover.has(Mask);
 726         MPM.addPass(HWAddressSanitizerPass(
 727             {CompileKernel, Recover,
 728              /*DisableOptimization=*/CodeGenOpts.OptimizationLevel == 0}));
 729       }
 730     };
 731     HWASanPass(SanitizerKind::HWAddress, false);
 732     HWASanPass(SanitizerKind::KernelHWAddress, true);
 733
 734     if (LangOpts.Sanitize.has(SanitizerKind::DataFlow)) {
 735       MPM.addPass(DataFlowSanitizerPass(LangOpts.NoSanitizeFiles));
 736     }
 737   };
 738   if (ClSanitizeOnOptimizerEarlyEP) {
 739     PB.registerOptimizerEarlyEPCallback(
 740         [SanitizersCallback](ModulePassManager &MPM, OptimizationLevel Level) {
 741           ModulePassManager NewMPM;
 742           SanitizersCallback(NewMPM, Level);
 743           if (!NewMPM.isEmpty()) {
 744             // Sanitizers can abandon<GlobalsAA>.
 745             NewMPM.addPass(RequireAnalysisPass<GlobalsAA, Module>());
 746             MPM.addPass(std::move(NewMPM));
 747           }
 748         });
 749   } else {
 750     // LastEP does not need GlobalsAA.
 751     PB.registerOptimizerLastEPCallback(SanitizersCallback);
 752   }
 753 }
 754
 755 void EmitAssemblyHelper::RunOptimizationPipeline(
 756     BackendAction Action, std::unique_ptr<raw_pwrite_stream> &OS,
 757     std::unique_ptr<llvm::ToolOutputFile> &ThinLinkOS) {
 758   std::optional<PGOOptions> PGOOpt;
 759
 760   if (CodeGenOpts.hasProfileIRInstr())
 761     // -fprofile-generate.
 762     PGOOpt = PGOOptions(
 763         CodeGenOpts.InstrProfileOutput.empty() ? getDefaultProfileGenName()
 764                                                : CodeGenOpts.InstrProfileOutput,
 765         "", "", nullptr, PGOOptions::IRInstr, PGOOptions::NoCSAction,
 766         CodeGenOpts.DebugInfoForProfiling);
 767   else if (CodeGenOpts.hasProfileIRUse()) {
 768     // -fprofile-use.
 769     auto CSAction = CodeGenOpts.hasProfileCSIRUse() ? PGOOptions::CSIRUse
 770                                                     : PGOOptions::NoCSAction;
 771     PGOOpt =
 772         PGOOptions(CodeGenOpts.ProfileInstrumentUsePath, "",
 773                    CodeGenOpts.ProfileRemappingFile, VFS, PGOOptions::IRUse,
 774                    CSAction, CodeGenOpts.DebugInfoForProfiling);
 775   } else if (!CodeGenOpts.SampleProfileFile.empty())
 776     // -fprofile-sample-use
 777     PGOOpt = PGOOptions(
 778         CodeGenOpts.SampleProfileFile, "", CodeGenOpts.ProfileRemappingFile,
 779         VFS, PGOOptions::SampleUse, PGOOptions::NoCSAction,
 780         CodeGenOpts.DebugInfoForProfiling, CodeGenOpts.PseudoProbeForProfiling);
 781   else if (CodeGenOpts.PseudoProbeForProfiling)
 782     // -fpseudo-probe-for-profiling
 783     PGOOpt = PGOOptions("", "", "", nullptr, PGOOptions::NoAction,
 784                         PGOOptions::NoCSAction,
 785                         CodeGenOpts.DebugInfoForProfiling, true);
 786   else if (CodeGenOpts.DebugInfoForProfiling)
 787     // -fdebug-info-for-profiling
 788     PGOOpt = PGOOptions("", "", "", nullptr, PGOOptions::NoAction,
 789                         PGOOptions::NoCSAction, true);
 790
 791   // Check to see if we want to generate a CS profile.
 792   if (CodeGenOpts.hasProfileCSIRInstr()) {
 793     assert(!CodeGenOpts.hasProfileCSIRUse() &&
 794            "Cannot have both CSProfileUse pass and CSProfileGen pass at "
 795            "the same time");
 796     if (PGOOpt) {
 797       assert(PGOOpt->Action != PGOOptions::IRInstr &&
 798              PGOOpt->Action != PGOOptions::SampleUse &&
 799              "Cannot run CSProfileGen pass with ProfileGen or SampleUse "
 800              " pass");
 801       PGOOpt->CSProfileGenFile = CodeGenOpts.InstrProfileOutput.empty()
 802                                      ? getDefaultProfileGenName()
 803                                      : CodeGenOpts.InstrProfileOutput;
 804       PGOOpt->CSAction = PGOOptions::CSIRInstr;
 805     } else
 806       PGOOpt =
 807           PGOOptions("",
 808                      CodeGenOpts.InstrProfileOutput.empty()
 809                          ? getDefaultProfileGenName()
 810                          : CodeGenOpts.InstrProfileOutput,
 811                      "", nullptr, PGOOptions::NoAction, PGOOptions::CSIRInstr,
 812                      CodeGenOpts.DebugInfoForProfiling);
 813   }
 814   if (TM)
 815     TM->setPGOOption(PGOOpt);
 816
 817   PipelineTuningOptions PTO;
 818   PTO.LoopUnrolling = CodeGenOpts.UnrollLoops;
 819   // For historical reasons, loop interleaving is set to mirror setting for loop
 820   // unrolling.
 821   PTO.LoopInterleaving = CodeGenOpts.UnrollLoops;
 822   PTO.LoopVectorization = CodeGenOpts.VectorizeLoop;
 823   PTO.SLPVectorization = CodeGenOpts.VectorizeSLP;
 824   PTO.MergeFunctions = CodeGenOpts.MergeFunctions;
 825   // Only enable CGProfilePass when using integrated assembler, since
 826   // non-integrated assemblers don't recognize .cgprofile section.
 827   PTO.CallGraphProfile = !CodeGenOpts.DisableIntegratedAS;
 828
 829   LoopAnalysisManager LAM;
 830   FunctionAnalysisManager FAM;
 831   CGSCCAnalysisManager CGAM;
 832   ModuleAnalysisManager MAM;
 833
 834   bool DebugPassStructure = CodeGenOpts.DebugPass == "Structure";
 835   PassInstrumentationCallbacks PIC;
 836   PrintPassOptions PrintPassOpts;
 837   PrintPassOpts.Indent = DebugPassStructure;
 838   PrintPassOpts.SkipAnalyses = DebugPassStructure;
 839   StandardInstrumentations SI(
 840       TheModule->getContext(),
 841       (CodeGenOpts.DebugPassManager || DebugPassStructure),
 842       /*VerifyEach*/ false, PrintPassOpts);
 843   SI.registerCallbacks(PIC, &MAM);
 844   PassBuilder PB(TM.get(), PTO, PGOOpt, &PIC);
 845
 846   // Handle the assignment tracking feature options.
 847   switch (CodeGenOpts.getAssignmentTrackingMode()) {
 848   case CodeGenOptions::AssignmentTrackingOpts::Forced:
 849     PB.registerPipelineStartEPCallback(
 850         [&](ModulePassManager &MPM, OptimizationLevel Level) {
 851           MPM.addPass(AssignmentTrackingPass());
 852         });
 853     break;
 854   case CodeGenOptions::AssignmentTrackingOpts::Enabled:
 855     // Disable assignment tracking in LTO builds for now as the performance
 856     // cost is too high. Disable for LLDB tuning due to llvm.org/PR43126.
 857     if (!CodeGenOpts.PrepareForThinLTO && !CodeGenOpts.PrepareForLTO &&
 858         CodeGenOpts.getDebuggerTuning() != llvm::DebuggerKind::LLDB) {
 859       PB.registerPipelineStartEPCallback(
 860           [&](ModulePassManager &MPM, OptimizationLevel Level) {
 861             // Only use assignment tracking if optimisations are enabled.
 862             if (Level != OptimizationLevel::O0)
 863               MPM.addPass(AssignmentTrackingPass());
 864           });
 865     }
 866     break;
 867   case CodeGenOptions::AssignmentTrackingOpts::Disabled:
 868     break;
 869   }
 870
 871   // Enable verify-debuginfo-preserve-each for new PM.
 872   DebugifyEachInstrumentation Debugify;
 873   DebugInfoPerPass DebugInfoBeforePass;
 874   if (CodeGenOpts.EnableDIPreservationVerify) {
 875     Debugify.setDebugifyMode(DebugifyMode::OriginalDebugInfo);
 876     Debugify.setDebugInfoBeforePass(DebugInfoBeforePass);
 877
 878     if (!CodeGenOpts.DIBugsReportFilePath.empty())
 879       Debugify.setOrigDIVerifyBugsReportFilePath(
 880           CodeGenOpts.DIBugsReportFilePath);
 881     Debugify.registerCallbacks(PIC, MAM);
 882   }
 883   // Attempt to load pass plugins and register their callbacks with PB.
 884   for (auto &PluginFN : CodeGenOpts.PassPlugins) {
 885     auto PassPlugin = PassPlugin::Load(PluginFN);
 886     if (PassPlugin) {
 887       PassPlugin->registerPassBuilderCallbacks(PB);
 888     } else {
 889       Diags.Report(diag::err_fe_unable_to_load_plugin)
 890           << PluginFN << toString(PassPlugin.takeError());
 891     }
 892   }
 893 #define HANDLE_EXTENSION(Ext)                                                  \
 894   get##Ext##PluginInfo().RegisterPassBuilderCallbacks(PB);
 895 #include "llvm/Support/Extension.def"
 896
 897   // Register the target library analysis directly and give it a customized
 898   // preset TLI.
 899   std::unique_ptr<TargetLibraryInfoImpl> TLII(
 900       createTLII(TargetTriple, CodeGenOpts));
 901   FAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
 902
 903   // Register all the basic analyses with the managers.
 904   PB.registerModuleAnalyses(MAM);
 905   PB.registerCGSCCAnalyses(CGAM);
 906   PB.registerFunctionAnalyses(FAM);
 907   PB.registerLoopAnalyses(LAM);
 908   PB.crossRegisterProxies(LAM, FAM, CGAM, MAM);
 909
 910   ModulePassManager MPM;
 911
 912   if (!CodeGenOpts.DisableLLVMPasses) {
 913     // Map our optimization levels into one of the distinct levels used to
 914     // configure the pipeline.
 915     OptimizationLevel Level = mapToLevel(CodeGenOpts);
 916
 917     bool IsThinLTO = CodeGenOpts.PrepareForThinLTO;
 918     bool IsLTO = CodeGenOpts.PrepareForLTO;
 919
 920     if (LangOpts.ObjCAutoRefCount) {
 921       PB.registerPipelineStartEPCallback(
 922           [](ModulePassManager &MPM, OptimizationLevel Level) {
 923             if (Level != OptimizationLevel::O0)
 924               MPM.addPass(
 925                   createModuleToFunctionPassAdaptor(ObjCARCExpandPass()));
 926           });
 927       PB.registerPipelineEarlySimplificationEPCallback(
 928           [](ModulePassManager &MPM, OptimizationLevel Level) {
 929             if (Level != OptimizationLevel::O0)
 930               MPM.addPass(ObjCARCAPElimPass());
 931           });
 932       PB.registerScalarOptimizerLateEPCallback(
 933           [](FunctionPassManager &FPM, OptimizationLevel Level) {
 934             if (Level != OptimizationLevel::O0)
 935               FPM.addPass(ObjCARCOptPass());
 936           });
 937     }
 938
 939     // If we reached here with a non-empty index file name, then the index
 940     // file was empty and we are not performing ThinLTO backend compilation
 941     // (used in testing in a distributed build environment).
 942     bool IsThinLTOPostLink = !CodeGenOpts.ThinLTOIndexFile.empty();
 943     // If so drop any the type test assume sequences inserted for whole program
 944     // vtables so that codegen doesn't complain.
 945     if (IsThinLTOPostLink)
 946       PB.registerPipelineStartEPCallback(
 947           [](ModulePassManager &MPM, OptimizationLevel Level) {
 948             MPM.addPass(LowerTypeTestsPass(/*ExportSummary=*/nullptr,
 949                                            /*ImportSummary=*/nullptr,
 950                                            /*DropTypeTests=*/true));
 951           });
 952
 953     if (CodeGenOpts.InstrumentFunctions ||
 954         CodeGenOpts.InstrumentFunctionEntryBare ||
 955         CodeGenOpts.InstrumentFunctionsAfterInlining ||
 956         CodeGenOpts.InstrumentForProfiling) {
 957       PB.registerPipelineStartEPCallback(
 958           [](ModulePassManager &MPM, OptimizationLevel Level) {
 959             MPM.addPass(createModuleToFunctionPassAdaptor(
 960                 EntryExitInstrumenterPass(/*PostInlining=*/false)));
 961           });
 962       PB.registerOptimizerLastEPCallback(
 963           [](ModulePassManager &MPM, OptimizationLevel Level) {
 964             MPM.addPass(createModuleToFunctionPassAdaptor(
 965                 EntryExitInstrumenterPass(/*PostInlining=*/true)));
 966           });
 967     }
 968
 969     // Register callbacks to schedule sanitizer passes at the appropriate part
 970     // of the pipeline.
 971     if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
 972       PB.registerScalarOptimizerLateEPCallback(
 973           [](FunctionPassManager &FPM, OptimizationLevel Level) {
 974             FPM.addPass(BoundsCheckingPass());
 975           });
 976
 977     // Don't add sanitizers if we are here from ThinLTO PostLink. That already
 978     // done on PreLink stage.
 979     if (!IsThinLTOPostLink) {
 980       addSanitizers(TargetTriple, CodeGenOpts, LangOpts, PB);
 981       addKCFIPass(TargetTriple, LangOpts, PB);
 982     }
 983
 984     if (std::optional<GCOVOptions> Options =
 985             getGCOVOptions(CodeGenOpts, LangOpts))
 986       PB.registerPipelineStartEPCallback(
 987           [Options](ModulePassManager &MPM, OptimizationLevel Level) {
 988             MPM.addPass(GCOVProfilerPass(*Options));
 989           });
 990     if (std::optional<InstrProfOptions> Options =
 991             getInstrProfOptions(CodeGenOpts, LangOpts))
 992       PB.registerPipelineStartEPCallback(
 993           [Options](ModulePassManager &MPM, OptimizationLevel Level) {
 994             MPM.addPass(InstrProfiling(*Options, false));
 995           });
 996
 997     // TODO: Consider passing the MemoryProfileOutput to the pass builder via
 998     // the PGOOptions, and set this up there.
 999     if (!CodeGenOpts.MemoryProfileOutput.empty()) {
1000       PB.registerOptimizerLastEPCallback(
1001           [](ModulePassManager &MPM, OptimizationLevel Level) {
1002             MPM.addPass(createModuleToFunctionPassAdaptor(MemProfilerPass()));
1003             MPM.addPass(ModuleMemProfilerPass());
1004           });
1005     }
1006
1007     if (IsThinLTO) {
1008       MPM = PB.buildThinLTOPreLinkDefaultPipeline(Level);
1009     } else if (IsLTO) {
1010       MPM = PB.buildLTOPreLinkDefaultPipeline(Level);
1011     } else {
1012       MPM = PB.buildPerModuleDefaultPipeline(Level);
1013     }
1014   }
1015
1016   // Add a verifier pass if requested. We don't have to do this if the action
1017   // requires code generation because there will already be a verifier pass in
1018   // the code-generation pipeline.
1019   if (!actionRequiresCodeGen(Action) && CodeGenOpts.VerifyModule)
1020     MPM.addPass(VerifierPass());
1021
1022   if (Action == Backend_EmitBC || Action == Backend_EmitLL) {
1023     if (CodeGenOpts.PrepareForThinLTO && !CodeGenOpts.DisableLLVMPasses) {
1024       if (!TheModule->getModuleFlag("EnableSplitLTOUnit"))
1025         TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
1026                                  CodeGenOpts.EnableSplitLTOUnit);
1027       if (Action == Backend_EmitBC) {
1028         if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
1029           ThinLinkOS = openOutputFile(CodeGenOpts.ThinLinkBitcodeFile);
1030           if (!ThinLinkOS)
1031             return;
1032         }
1033         MPM.addPass(ThinLTOBitcodeWriterPass(*OS, ThinLinkOS ? &ThinLinkOS->os()
1034                                                              : nullptr));
1035       } else {
1036         MPM.addPass(PrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists,
1037                                     /*EmitLTOSummary=*/true));
1038       }
1039
1040     } else {
1041       // Emit a module summary by default for Regular LTO except for ld64
1042       // targets
1043       bool EmitLTOSummary = shouldEmitRegularLTOSummary();
1044       if (EmitLTOSummary) {
1045         if (!TheModule->getModuleFlag("ThinLTO"))
1046           TheModule->addModuleFlag(Module::Error, "ThinLTO", uint32_t(0));
1047         if (!TheModule->getModuleFlag("EnableSplitLTOUnit"))
1048           TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
1049                                    uint32_t(1));
1050       }
1051       if (Action == Backend_EmitBC)
1052         MPM.addPass(BitcodeWriterPass(*OS, CodeGenOpts.EmitLLVMUseLists,
1053                                       EmitLTOSummary));
1054       else
1055         MPM.addPass(PrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists,
1056                                     EmitLTOSummary));
1057     }
1058   }
1059
1060   // Now that we have all of the passes ready, run them.
1061   {
1062     PrettyStackTraceString CrashInfo("Optimizer");
1063     llvm::TimeTraceScope TimeScope("Optimizer");
1064     MPM.run(*TheModule, MAM);
1065   }
1066 }
1067
1068 void EmitAssemblyHelper::RunCodegenPipeline(
1069     BackendAction Action, std::unique_ptr<raw_pwrite_stream> &OS,
1070     std::unique_ptr<llvm::ToolOutputFile> &DwoOS) {
1071   // We still use the legacy PM to run the codegen pipeline since the new PM
1072   // does not work with the codegen pipeline.
1073   // FIXME: make the new PM work with the codegen pipeline.
1074   legacy::PassManager CodeGenPasses;
1075
1076   // Append any output we need to the pass manager.
1077   switch (Action) {
1078   case Backend_EmitAssembly:
1079   case Backend_EmitMCNull:
1080   case Backend_EmitObj:
1081     CodeGenPasses.add(
1082         createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
1083     if (!CodeGenOpts.SplitDwarfOutput.empty()) {
1084       DwoOS = openOutputFile(CodeGenOpts.SplitDwarfOutput);
1085       if (!DwoOS)
1086         return;
1087     }
1088     if (!AddEmitPasses(CodeGenPasses, Action, *OS,
1089                        DwoOS ? &DwoOS->os() : nullptr))
1090       // FIXME: Should we handle this error differently?
1091       return;
1092     break;
1093   default:
1094     return;
1095   }
1096
1097   {
1098     PrettyStackTraceString CrashInfo("Code generation");
1099     llvm::TimeTraceScope TimeScope("CodeGenPasses");
1100     CodeGenPasses.run(*TheModule);
1101   }
1102 }
1103
1104 void EmitAssemblyHelper::EmitAssembly(BackendAction Action,
1105                                       std::unique_ptr<raw_pwrite_stream> OS) {
1106   TimeRegion Region(CodeGenOpts.TimePasses ? &CodeGenerationTime : nullptr);
1107   setCommandLineOpts(CodeGenOpts);
1108
1109   bool RequiresCodeGen = actionRequiresCodeGen(Action);
1110   CreateTargetMachine(RequiresCodeGen);
1111
1112   if (RequiresCodeGen && !TM)
1113     return;
1114   if (TM)
1115     TheModule->setDataLayout(TM->createDataLayout());
1116
1117   // Before executing passes, print the final values of the LLVM options.
1118   cl::PrintOptionValues();
1119
1120   std::unique_ptr<llvm::ToolOutputFile> ThinLinkOS, DwoOS;
1121   RunOptimizationPipeline(Action, OS, ThinLinkOS);
1122   RunCodegenPipeline(Action, OS, DwoOS);
1123
1124   if (ThinLinkOS)
1125     ThinLinkOS->keep();
1126   if (DwoOS)
1127     DwoOS->keep();
1128 }
1129
1130 static void runThinLTOBackend(
1131     DiagnosticsEngine &Diags, ModuleSummaryIndex *CombinedIndex, Module *M,
1132     const HeaderSearchOptions &HeaderOpts, const CodeGenOptions &CGOpts,
1133     const clang::TargetOptions &TOpts, const LangOptions &LOpts,
1134     std::unique_ptr<raw_pwrite_stream> OS, std::string SampleProfile,
1135     std::string ProfileRemapping, BackendAction Action) {
1136   StringMap<DenseMap<GlobalValue::GUID, GlobalValueSummary *>>
1137       ModuleToDefinedGVSummaries;
1138   CombinedIndex->collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
1139
1140   setCommandLineOpts(CGOpts);
1141
1142   // We can simply import the values mentioned in the combined index, since
1143   // we should only invoke this using the individual indexes written out
1144   // via a WriteIndexesThinBackend.
1145   FunctionImporter::ImportMapTy ImportList;
1146   if (!lto::initImportList(*M, *CombinedIndex, ImportList))
1147     return;
1148
1149   auto AddStream = [&](size_t Task, const Twine &ModuleName) {
1150     return std::make_unique<CachedFileStream>(std::move(OS),
1151                                               CGOpts.ObjectFilenameForDebug);
1152   };
1153   lto::Config Conf;
1154   if (CGOpts.SaveTempsFilePrefix != "") {
1155     if (Error E = Conf.addSaveTemps(CGOpts.SaveTempsFilePrefix + ".",
1156                                     /* UseInputModulePath */ false)) {
1157       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1158         errs() << "Error setting up ThinLTO save-temps: " << EIB.message()
1159                << '\n';
1160       });
1161     }
1162   }
1163   Conf.CPU = TOpts.CPU;
1164   Conf.CodeModel = getCodeModel(CGOpts);
1165   Conf.MAttrs = TOpts.Features;
1166   Conf.RelocModel = CGOpts.RelocationModel;
1167   std::optional<CodeGenOpt::Level> OptLevelOrNone =
1168       CodeGenOpt::getLevel(CGOpts.OptimizationLevel);
1169   assert(OptLevelOrNone && "Invalid optimization level!");
1170   Conf.CGOptLevel = *OptLevelOrNone;
1171   Conf.OptLevel = CGOpts.OptimizationLevel;
1172   initTargetOptions(Diags, Conf.Options, CGOpts, TOpts, LOpts, HeaderOpts);
1173   Conf.SampleProfile = std::move(SampleProfile);
1174   Conf.PTO.LoopUnrolling = CGOpts.UnrollLoops;
1175   // For historical reasons, loop interleaving is set to mirror setting for loop
1176   // unrolling.
1177   Conf.PTO.LoopInterleaving = CGOpts.UnrollLoops;
1178   Conf.PTO.LoopVectorization = CGOpts.VectorizeLoop;
1179   Conf.PTO.SLPVectorization = CGOpts.VectorizeSLP;
1180   // Only enable CGProfilePass when using integrated assembler, since
1181   // non-integrated assemblers don't recognize .cgprofile section.
1182   Conf.PTO.CallGraphProfile = !CGOpts.DisableIntegratedAS;
1183
1184   // Context sensitive profile.
1185   if (CGOpts.hasProfileCSIRInstr()) {
1186     Conf.RunCSIRInstr = true;
1187     Conf.CSIRProfile = std::move(CGOpts.InstrProfileOutput);
1188   } else if (CGOpts.hasProfileCSIRUse()) {
1189     Conf.RunCSIRInstr = false;
1190     Conf.CSIRProfile = std::move(CGOpts.ProfileInstrumentUsePath);
1191   }
1192
1193   Conf.ProfileRemapping = std::move(ProfileRemapping);
1194   Conf.DebugPassManager = CGOpts.DebugPassManager;
1195   Conf.RemarksWithHotness = CGOpts.DiagnosticsWithHotness;
1196   Conf.RemarksFilename = CGOpts.OptRecordFile;
1197   Conf.RemarksPasses = CGOpts.OptRecordPasses;
1198   Conf.RemarksFormat = CGOpts.OptRecordFormat;
1199   Conf.SplitDwarfFile = CGOpts.SplitDwarfFile;
1200   Conf.SplitDwarfOutput = CGOpts.SplitDwarfOutput;
1201   switch (Action) {
1202   case Backend_EmitNothing:
1203     Conf.PreCodeGenModuleHook = [](size_t Task, const Module &Mod) {
1204       return false;
1205     };
1206     break;
1207   case Backend_EmitLL:
1208     Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1209       M->print(*OS, nullptr, CGOpts.EmitLLVMUseLists);
1210       return false;
1211     };
1212     break;
1213   case Backend_EmitBC:
1214     Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1215       WriteBitcodeToFile(*M, *OS, CGOpts.EmitLLVMUseLists);
1216       return false;
1217     };
1218     break;
1219   default:
1220     Conf.CGFileType = getCodeGenFileType(Action);
1221     break;
1222   }
1223   if (Error E =
1224           thinBackend(Conf, -1, AddStream, *M, *CombinedIndex, ImportList,
1225                       ModuleToDefinedGVSummaries[M->getModuleIdentifier()],
1226                       /* ModuleMap */ nullptr, CGOpts.CmdArgs)) {
1227     handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1228       errs() << "Error running ThinLTO backend: " << EIB.message() << '\n';
1229     });
1230   }
1231 }
1232
1233 void clang::EmitBackendOutput(DiagnosticsEngine &Diags,
1234                               const HeaderSearchOptions &HeaderOpts,
1235                               const CodeGenOptions &CGOpts,
1236                               const clang::TargetOptions &TOpts,
1237                               const LangOptions &LOpts, StringRef TDesc,
1238                               Module *M, BackendAction Action,
1239                               IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS,
1240                               std::unique_ptr<raw_pwrite_stream> OS) {
1241
1242   llvm::TimeTraceScope TimeScope("Backend");
1243
1244   std::unique_ptr<llvm::Module> EmptyModule;
1245   if (!CGOpts.ThinLTOIndexFile.empty()) {
1246     // If we are performing a ThinLTO importing compile, load the function index
1247     // into memory and pass it into runThinLTOBackend, which will run the
1248     // function importer and invoke LTO passes.
1249     std::unique_ptr<ModuleSummaryIndex> CombinedIndex;
1250     if (Error E = llvm::getModuleSummaryIndexForFile(
1251                       CGOpts.ThinLTOIndexFile,
1252                       /*IgnoreEmptyThinLTOIndexFile*/ true)
1253                       .moveInto(CombinedIndex)) {
1254       logAllUnhandledErrors(std::move(E), errs(),
1255                             "Error loading index file '" +
1256                             CGOpts.ThinLTOIndexFile + "': ");
1257       return;
1258     }
1259
1260     // A null CombinedIndex means we should skip ThinLTO compilation
1261     // (LLVM will optionally ignore empty index files, returning null instead
1262     // of an error).
1263     if (CombinedIndex) {
1264       if (!CombinedIndex->skipModuleByDistributedBackend()) {
1265         runThinLTOBackend(Diags, CombinedIndex.get(), M, HeaderOpts, CGOpts,
1266                           TOpts, LOpts, std::move(OS), CGOpts.SampleProfileFile,
1267                           CGOpts.ProfileRemappingFile, Action);
1268         return;
1269       }
1270       // Distributed indexing detected that nothing from the module is needed
1271       // for the final linking. So we can skip the compilation. We sill need to
1272       // output an empty object file to make sure that a linker does not fail
1273       // trying to read it. Also for some features, like CFI, we must skip
1274       // the compilation as CombinedIndex does not contain all required
1275       // information.
1276       EmptyModule = std::make_unique<llvm::Module>("empty", M->getContext());
1277       EmptyModule->setTargetTriple(M->getTargetTriple());
1278       M = EmptyModule.get();
1279     }
1280   }
1281
1282   EmitAssemblyHelper AsmHelper(Diags, HeaderOpts, CGOpts, TOpts, LOpts, M, VFS);
1283   AsmHelper.EmitAssembly(Action, std::move(OS));
1284
1285   // Verify clang's TargetInfo DataLayout against the LLVM TargetMachine's
1286   // DataLayout.
1287   if (AsmHelper.TM) {
1288     std::string DLDesc = M->getDataLayout().getStringRepresentation();
1289     if (DLDesc != TDesc) {
1290       unsigned DiagID = Diags.getCustomDiagID(
1291           DiagnosticsEngine::Error, "backend data layout '%0' does not match "
1292                                     "expected target description '%1'");
1293       Diags.Report(DiagID) << DLDesc << TDesc;
1294     }
1295   }
1296 }
1297
1298 // With -fembed-bitcode, save a copy of the llvm IR as data in the
1299 // __LLVM,__bitcode section.
1300 void clang::EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts,
1301                          llvm::MemoryBufferRef Buf) {
1302   if (CGOpts.getEmbedBitcode() == CodeGenOptions::Embed_Off)
1303     return;
1304   llvm::embedBitcodeInModule(
1305       *M, Buf, CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Marker,
1306       CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Bitcode,
1307       CGOpts.CmdArgs);
1308 }
1309
1310 void clang::EmbedObject(llvm::Module *M, const CodeGenOptions &CGOpts,
1311                         DiagnosticsEngine &Diags) {
1312   if (CGOpts.OffloadObjects.empty())
1313     return;
1314
1315   for (StringRef OffloadObject : CGOpts.OffloadObjects) {
1316     llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> ObjectOrErr =
1317         llvm::MemoryBuffer::getFileOrSTDIN(OffloadObject);
1318     if (std::error_code EC = ObjectOrErr.getError()) {
1319       auto DiagID = Diags.getCustomDiagID(DiagnosticsEngine::Error,
1320                                           "could not open '%0' for embedding");
1321       Diags.Report(DiagID) << OffloadObject;
1322       return;
1323     }
1324
1325     llvm::embedBufferInModule(*M, **ObjectOrErr, ".llvm.offloading",
1326                               Align(object::OffloadBinary::getAlignment()));
1327   }
1328 }