contrib/llvm-project/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/ADT/Triple.h"
  21 #include "llvm/Analysis/TargetLibraryInfo.h"
  22 #include "llvm/Analysis/TargetTransformInfo.h"
  23 #include "llvm/Bitcode/BitcodeReader.h"
  24 #include "llvm/Bitcode/BitcodeWriter.h"
  25 #include "llvm/Bitcode/BitcodeWriterPass.h"
  26 #include "llvm/CodeGen/RegAllocRegistry.h"
  27 #include "llvm/CodeGen/SchedulerRegistry.h"
  28 #include "llvm/CodeGen/TargetSubtargetInfo.h"
  29 #include "llvm/IR/DataLayout.h"
  30 #include "llvm/IR/IRPrintingPasses.h"
  31 #include "llvm/IR/LegacyPassManager.h"
  32 #include "llvm/IR/Module.h"
  33 #include "llvm/IR/ModuleSummaryIndex.h"
  34 #include "llvm/IR/Verifier.h"
  35 #include "llvm/LTO/LTOBackend.h"
  36 #include "llvm/MC/MCAsmInfo.h"
  37 #include "llvm/MC/SubtargetFeature.h"
  38 #include "llvm/Passes/PassBuilder.h"
  39 #include "llvm/Passes/PassPlugin.h"
  40 #include "llvm/Passes/StandardInstrumentations.h"
  41 #include "llvm/Support/BuryPointer.h"
  42 #include "llvm/Support/CommandLine.h"
  43 #include "llvm/Support/MemoryBuffer.h"
  44 #include "llvm/Support/PrettyStackTrace.h"
  45 #include "llvm/Support/TargetRegistry.h"
  46 #include "llvm/Support/TimeProfiler.h"
  47 #include "llvm/Support/Timer.h"
  48 #include "llvm/Support/raw_ostream.h"
  49 #include "llvm/Target/TargetMachine.h"
  50 #include "llvm/Target/TargetOptions.h"
  51 #include "llvm/Transforms/Coroutines.h"
  52 #include "llvm/Transforms/IPO.h"
  53 #include "llvm/Transforms/IPO/AlwaysInliner.h"
  54 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
  55 #include "llvm/Transforms/IPO/ThinLTOBitcodeWriter.h"
  56 #include "llvm/Transforms/InstCombine/InstCombine.h"
  57 #include "llvm/Transforms/Instrumentation.h"
  58 #include "llvm/Transforms/Instrumentation/AddressSanitizer.h"
  59 #include "llvm/Transforms/Instrumentation/BoundsChecking.h"
  60 #include "llvm/Transforms/Instrumentation/GCOVProfiler.h"
  61 #include "llvm/Transforms/Instrumentation/HWAddressSanitizer.h"
  62 #include "llvm/Transforms/Instrumentation/InstrProfiling.h"
  63 #include "llvm/Transforms/Instrumentation/MemorySanitizer.h"
  64 #include "llvm/Transforms/Instrumentation/SanitizerCoverage.h"
  65 #include "llvm/Transforms/Instrumentation/ThreadSanitizer.h"
  66 #include "llvm/Transforms/ObjCARC.h"
  67 #include "llvm/Transforms/Scalar.h"
  68 #include "llvm/Transforms/Scalar/GVN.h"
  69 #include "llvm/Transforms/Utils.h"
  70 #include "llvm/Transforms/Utils/CanonicalizeAliases.h"
  71 #include "llvm/Transforms/Utils/EntryExitInstrumenter.h"
  72 #include "llvm/Transforms/Utils/NameAnonGlobals.h"
  73 #include "llvm/Transforms/Utils/SymbolRewriter.h"
  74 #include <memory>
  75 using namespace clang;
  76 using namespace llvm;
  77
  78 #define HANDLE_EXTENSION(Ext)                                                  \
  79   llvm::PassPluginLibraryInfo get##Ext##PluginInfo();
  80 #include "llvm/Support/Extension.def"
  81
  82 namespace {
  83
  84 // Default filename used for profile generation.
  85 static constexpr StringLiteral DefaultProfileGenName = "default_%m.profraw";
  86
  87 class EmitAssemblyHelper {
  88   DiagnosticsEngine &Diags;
  89   const HeaderSearchOptions &HSOpts;
  90   const CodeGenOptions &CodeGenOpts;
  91   const clang::TargetOptions &TargetOpts;
  92   const LangOptions &LangOpts;
  93   Module *TheModule;
  94
  95   Timer CodeGenerationTime;
  96
  97   std::unique_ptr<raw_pwrite_stream> OS;
  98
  99   TargetIRAnalysis getTargetIRAnalysis() const {
 100     if (TM)
 101       return TM->getTargetIRAnalysis();
 102
 103     return TargetIRAnalysis();
 104   }
 105
 106   void CreatePasses(legacy::PassManager &MPM, legacy::FunctionPassManager &FPM);
 107
 108   /// Generates the TargetMachine.
 109   /// Leaves TM unchanged if it is unable to create the target machine.
 110   /// Some of our clang tests specify triples which are not built
 111   /// into clang. This is okay because these tests check the generated
 112   /// IR, and they require DataLayout which depends on the triple.
 113   /// In this case, we allow this method to fail and not report an error.
 114   /// When MustCreateTM is used, we print an error if we are unable to load
 115   /// the requested target.
 116   void CreateTargetMachine(bool MustCreateTM);
 117
 118   /// Add passes necessary to emit assembly or LLVM IR.
 119   ///
 120   /// \return True on success.
 121   bool AddEmitPasses(legacy::PassManager &CodeGenPasses, BackendAction Action,
 122                      raw_pwrite_stream &OS, raw_pwrite_stream *DwoOS);
 123
 124   std::unique_ptr<llvm::ToolOutputFile> openOutputFile(StringRef Path) {
 125     std::error_code EC;
 126     auto F = std::make_unique<llvm::ToolOutputFile>(Path, EC,
 127                                                      llvm::sys::fs::OF_None);
 128     if (EC) {
 129       Diags.Report(diag::err_fe_unable_to_open_output) << Path << EC.message();
 130       F.reset();
 131     }
 132     return F;
 133   }
 134
 135 public:
 136   EmitAssemblyHelper(DiagnosticsEngine &_Diags,
 137                      const HeaderSearchOptions &HeaderSearchOpts,
 138                      const CodeGenOptions &CGOpts,
 139                      const clang::TargetOptions &TOpts,
 140                      const LangOptions &LOpts, Module *M)
 141       : Diags(_Diags), HSOpts(HeaderSearchOpts), CodeGenOpts(CGOpts),
 142         TargetOpts(TOpts), LangOpts(LOpts), TheModule(M),
 143         CodeGenerationTime("codegen", "Code Generation Time") {}
 144
 145   ~EmitAssemblyHelper() {
 146     if (CodeGenOpts.DisableFree)
 147       BuryPointer(std::move(TM));
 148   }
 149
 150   std::unique_ptr<TargetMachine> TM;
 151
 152   void EmitAssembly(BackendAction Action,
 153                     std::unique_ptr<raw_pwrite_stream> OS);
 154
 155   void EmitAssemblyWithNewPassManager(BackendAction Action,
 156                                       std::unique_ptr<raw_pwrite_stream> OS);
 157 };
 158
 159 // We need this wrapper to access LangOpts and CGOpts from extension functions
 160 // that we add to the PassManagerBuilder.
 161 class PassManagerBuilderWrapper : public PassManagerBuilder {
 162 public:
 163   PassManagerBuilderWrapper(const Triple &TargetTriple,
 164                             const CodeGenOptions &CGOpts,
 165                             const LangOptions &LangOpts)
 166       : PassManagerBuilder(), TargetTriple(TargetTriple), CGOpts(CGOpts),
 167         LangOpts(LangOpts) {}
 168   const Triple &getTargetTriple() const { return TargetTriple; }
 169   const CodeGenOptions &getCGOpts() const { return CGOpts; }
 170   const LangOptions &getLangOpts() const { return LangOpts; }
 171
 172 private:
 173   const Triple &TargetTriple;
 174   const CodeGenOptions &CGOpts;
 175   const LangOptions &LangOpts;
 176 };
 177 }
 178
 179 static void addObjCARCAPElimPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
 180   if (Builder.OptLevel > 0)
 181     PM.add(createObjCARCAPElimPass());
 182 }
 183
 184 static void addObjCARCExpandPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
 185   if (Builder.OptLevel > 0)
 186     PM.add(createObjCARCExpandPass());
 187 }
 188
 189 static void addObjCARCOptPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
 190   if (Builder.OptLevel > 0)
 191     PM.add(createObjCARCOptPass());
 192 }
 193
 194 static void addAddDiscriminatorsPass(const PassManagerBuilder &Builder,
 195                                      legacy::PassManagerBase &PM) {
 196   PM.add(createAddDiscriminatorsPass());
 197 }
 198
 199 static void addBoundsCheckingPass(const PassManagerBuilder &Builder,
 200                                   legacy::PassManagerBase &PM) {
 201   PM.add(createBoundsCheckingLegacyPass());
 202 }
 203
 204 static SanitizerCoverageOptions
 205 getSancovOptsFromCGOpts(const CodeGenOptions &CGOpts) {
 206   SanitizerCoverageOptions Opts;
 207   Opts.CoverageType =
 208       static_cast<SanitizerCoverageOptions::Type>(CGOpts.SanitizeCoverageType);
 209   Opts.IndirectCalls = CGOpts.SanitizeCoverageIndirectCalls;
 210   Opts.TraceBB = CGOpts.SanitizeCoverageTraceBB;
 211   Opts.TraceCmp = CGOpts.SanitizeCoverageTraceCmp;
 212   Opts.TraceDiv = CGOpts.SanitizeCoverageTraceDiv;
 213   Opts.TraceGep = CGOpts.SanitizeCoverageTraceGep;
 214   Opts.Use8bitCounters = CGOpts.SanitizeCoverage8bitCounters;
 215   Opts.TracePC = CGOpts.SanitizeCoverageTracePC;
 216   Opts.TracePCGuard = CGOpts.SanitizeCoverageTracePCGuard;
 217   Opts.NoPrune = CGOpts.SanitizeCoverageNoPrune;
 218   Opts.Inline8bitCounters = CGOpts.SanitizeCoverageInline8bitCounters;
 219   Opts.PCTable = CGOpts.SanitizeCoveragePCTable;
 220   Opts.StackDepth = CGOpts.SanitizeCoverageStackDepth;
 221   return Opts;
 222 }
 223
 224 static void addSanitizerCoveragePass(const PassManagerBuilder &Builder,
 225                                      legacy::PassManagerBase &PM) {
 226   const PassManagerBuilderWrapper &BuilderWrapper =
 227       static_cast<const PassManagerBuilderWrapper &>(Builder);
 228   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
 229   auto Opts = getSancovOptsFromCGOpts(CGOpts);
 230   PM.add(createModuleSanitizerCoverageLegacyPassPass(Opts));
 231 }
 232
 233 // Check if ASan should use GC-friendly instrumentation for globals.
 234 // First of all, there is no point if -fdata-sections is off (expect for MachO,
 235 // where this is not a factor). Also, on ELF this feature requires an assembler
 236 // extension that only works with -integrated-as at the moment.
 237 static bool asanUseGlobalsGC(const Triple &T, const CodeGenOptions &CGOpts) {
 238   if (!CGOpts.SanitizeAddressGlobalsDeadStripping)
 239     return false;
 240   switch (T.getObjectFormat()) {
 241   case Triple::MachO:
 242   case Triple::COFF:
 243     return true;
 244   case Triple::ELF:
 245     return CGOpts.DataSections && !CGOpts.DisableIntegratedAS;
 246   case Triple::XCOFF:
 247     llvm::report_fatal_error("ASan not implemented for XCOFF.");
 248   case Triple::Wasm:
 249   case Triple::UnknownObjectFormat:
 250     break;
 251   }
 252   return false;
 253 }
 254
 255 static void addAddressSanitizerPasses(const PassManagerBuilder &Builder,
 256                                       legacy::PassManagerBase &PM) {
 257   const PassManagerBuilderWrapper &BuilderWrapper =
 258       static_cast<const PassManagerBuilderWrapper&>(Builder);
 259   const Triple &T = BuilderWrapper.getTargetTriple();
 260   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
 261   bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Address);
 262   bool UseAfterScope = CGOpts.SanitizeAddressUseAfterScope;
 263   bool UseOdrIndicator = CGOpts.SanitizeAddressUseOdrIndicator;
 264   bool UseGlobalsGC = asanUseGlobalsGC(T, CGOpts);
 265   PM.add(createAddressSanitizerFunctionPass(/*CompileKernel*/ false, Recover,
 266                                             UseAfterScope));
 267   PM.add(createModuleAddressSanitizerLegacyPassPass(
 268       /*CompileKernel*/ false, Recover, UseGlobalsGC, UseOdrIndicator));
 269 }
 270
 271 static void addKernelAddressSanitizerPasses(const PassManagerBuilder &Builder,
 272                                             legacy::PassManagerBase &PM) {
 273   PM.add(createAddressSanitizerFunctionPass(
 274       /*CompileKernel*/ true, /*Recover*/ true, /*UseAfterScope*/ false));
 275   PM.add(createModuleAddressSanitizerLegacyPassPass(
 276       /*CompileKernel*/ true, /*Recover*/ true, /*UseGlobalsGC*/ true,
 277       /*UseOdrIndicator*/ false));
 278 }
 279
 280 static void addHWAddressSanitizerPasses(const PassManagerBuilder &Builder,
 281                                             legacy::PassManagerBase &PM) {
 282   const PassManagerBuilderWrapper &BuilderWrapper =
 283       static_cast<const PassManagerBuilderWrapper &>(Builder);
 284   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
 285   bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::HWAddress);
 286   PM.add(
 287       createHWAddressSanitizerLegacyPassPass(/*CompileKernel*/ false, Recover));
 288 }
 289
 290 static void addKernelHWAddressSanitizerPasses(const PassManagerBuilder &Builder,
 291                                             legacy::PassManagerBase &PM) {
 292   PM.add(createHWAddressSanitizerLegacyPassPass(
 293       /*CompileKernel*/ true, /*Recover*/ true));
 294 }
 295
 296 static void addGeneralOptsForMemorySanitizer(const PassManagerBuilder &Builder,
 297                                              legacy::PassManagerBase &PM,
 298                                              bool CompileKernel) {
 299   const PassManagerBuilderWrapper &BuilderWrapper =
 300       static_cast<const PassManagerBuilderWrapper&>(Builder);
 301   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
 302   int TrackOrigins = CGOpts.SanitizeMemoryTrackOrigins;
 303   bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Memory);
 304   PM.add(createMemorySanitizerLegacyPassPass(
 305       MemorySanitizerOptions{TrackOrigins, Recover, CompileKernel}));
 306
 307   // MemorySanitizer inserts complex instrumentation that mostly follows
 308   // the logic of the original code, but operates on "shadow" values.
 309   // It can benefit from re-running some general purpose optimization passes.
 310   if (Builder.OptLevel > 0) {
 311     PM.add(createEarlyCSEPass());
 312     PM.add(createReassociatePass());
 313     PM.add(createLICMPass());
 314     PM.add(createGVNPass());
 315     PM.add(createInstructionCombiningPass());
 316     PM.add(createDeadStoreEliminationPass());
 317   }
 318 }
 319
 320 static void addMemorySanitizerPass(const PassManagerBuilder &Builder,
 321                                    legacy::PassManagerBase &PM) {
 322   addGeneralOptsForMemorySanitizer(Builder, PM, /*CompileKernel*/ false);
 323 }
 324
 325 static void addKernelMemorySanitizerPass(const PassManagerBuilder &Builder,
 326                                          legacy::PassManagerBase &PM) {
 327   addGeneralOptsForMemorySanitizer(Builder, PM, /*CompileKernel*/ true);
 328 }
 329
 330 static void addThreadSanitizerPass(const PassManagerBuilder &Builder,
 331                                    legacy::PassManagerBase &PM) {
 332   PM.add(createThreadSanitizerLegacyPassPass());
 333 }
 334
 335 static void addDataFlowSanitizerPass(const PassManagerBuilder &Builder,
 336                                      legacy::PassManagerBase &PM) {
 337   const PassManagerBuilderWrapper &BuilderWrapper =
 338       static_cast<const PassManagerBuilderWrapper&>(Builder);
 339   const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
 340   PM.add(createDataFlowSanitizerPass(LangOpts.SanitizerBlacklistFiles));
 341 }
 342
 343 static TargetLibraryInfoImpl *createTLII(llvm::Triple &TargetTriple,
 344                                          const CodeGenOptions &CodeGenOpts) {
 345   TargetLibraryInfoImpl *TLII = new TargetLibraryInfoImpl(TargetTriple);
 346
 347   switch (CodeGenOpts.getVecLib()) {
 348   case CodeGenOptions::Accelerate:
 349     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::Accelerate);
 350     break;
 351   case CodeGenOptions::MASSV:
 352     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::MASSV);
 353     break;
 354   case CodeGenOptions::SVML:
 355     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::SVML);
 356     break;
 357   default:
 358     break;
 359   }
 360   return TLII;
 361 }
 362
 363 static void addSymbolRewriterPass(const CodeGenOptions &Opts,
 364                                   legacy::PassManager *MPM) {
 365   llvm::SymbolRewriter::RewriteDescriptorList DL;
 366
 367   llvm::SymbolRewriter::RewriteMapParser MapParser;
 368   for (const auto &MapFile : Opts.RewriteMapFiles)
 369     MapParser.parse(MapFile, &DL);
 370
 371   MPM->add(createRewriteSymbolsPass(DL));
 372 }
 373
 374 static CodeGenOpt::Level getCGOptLevel(const CodeGenOptions &CodeGenOpts) {
 375   switch (CodeGenOpts.OptimizationLevel) {
 376   default:
 377     llvm_unreachable("Invalid optimization level!");
 378   case 0:
 379     return CodeGenOpt::None;
 380   case 1:
 381     return CodeGenOpt::Less;
 382   case 2:
 383     return CodeGenOpt::Default; // O2/Os/Oz
 384   case 3:
 385     return CodeGenOpt::Aggressive;
 386   }
 387 }
 388
 389 static Optional<llvm::CodeModel::Model>
 390 getCodeModel(const CodeGenOptions &CodeGenOpts) {
 391   unsigned CodeModel = llvm::StringSwitch<unsigned>(CodeGenOpts.CodeModel)
 392                            .Case("tiny", llvm::CodeModel::Tiny)
 393                            .Case("small", llvm::CodeModel::Small)
 394                            .Case("kernel", llvm::CodeModel::Kernel)
 395                            .Case("medium", llvm::CodeModel::Medium)
 396                            .Case("large", llvm::CodeModel::Large)
 397                            .Case("default", ~1u)
 398                            .Default(~0u);
 399   assert(CodeModel != ~0u && "invalid code model!");
 400   if (CodeModel == ~1u)
 401     return None;
 402   return static_cast<llvm::CodeModel::Model>(CodeModel);
 403 }
 404
 405 static CodeGenFileType getCodeGenFileType(BackendAction Action) {
 406   if (Action == Backend_EmitObj)
 407     return CGFT_ObjectFile;
 408   else if (Action == Backend_EmitMCNull)
 409     return CGFT_Null;
 410   else {
 411     assert(Action == Backend_EmitAssembly && "Invalid action!");
 412     return CGFT_AssemblyFile;
 413   }
 414 }
 415
 416 static void initTargetOptions(llvm::TargetOptions &Options,
 417                               const CodeGenOptions &CodeGenOpts,
 418                               const clang::TargetOptions &TargetOpts,
 419                               const LangOptions &LangOpts,
 420                               const HeaderSearchOptions &HSOpts) {
 421   Options.ThreadModel =
 422       llvm::StringSwitch<llvm::ThreadModel::Model>(CodeGenOpts.ThreadModel)
 423           .Case("posix", llvm::ThreadModel::POSIX)
 424           .Case("single", llvm::ThreadModel::Single);
 425
 426   // Set float ABI type.
 427   assert((CodeGenOpts.FloatABI == "soft" || CodeGenOpts.FloatABI == "softfp" ||
 428           CodeGenOpts.FloatABI == "hard" || CodeGenOpts.FloatABI.empty()) &&
 429          "Invalid Floating Point ABI!");
 430   Options.FloatABIType =
 431       llvm::StringSwitch<llvm::FloatABI::ABIType>(CodeGenOpts.FloatABI)
 432           .Case("soft", llvm::FloatABI::Soft)
 433           .Case("softfp", llvm::FloatABI::Soft)
 434           .Case("hard", llvm::FloatABI::Hard)
 435           .Default(llvm::FloatABI::Default);
 436
 437   // Set FP fusion mode.
 438   switch (LangOpts.getDefaultFPContractMode()) {
 439   case LangOptions::FPC_Off:
 440     // Preserve any contraction performed by the front-end.  (Strict performs
 441     // splitting of the muladd intrinsic in the backend.)
 442     Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
 443     break;
 444   case LangOptions::FPC_On:
 445     Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
 446     break;
 447   case LangOptions::FPC_Fast:
 448     Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
 449     break;
 450   }
 451
 452   Options.UseInitArray = CodeGenOpts.UseInitArray;
 453   Options.DisableIntegratedAS = CodeGenOpts.DisableIntegratedAS;
 454   Options.CompressDebugSections = CodeGenOpts.getCompressDebugSections();
 455   Options.RelaxELFRelocations = CodeGenOpts.RelaxELFRelocations;
 456
 457   // Set EABI version.
 458   Options.EABIVersion = TargetOpts.EABIVersion;
 459
 460   if (LangOpts.SjLjExceptions)
 461     Options.ExceptionModel = llvm::ExceptionHandling::SjLj;
 462   if (LangOpts.SEHExceptions)
 463     Options.ExceptionModel = llvm::ExceptionHandling::WinEH;
 464   if (LangOpts.DWARFExceptions)
 465     Options.ExceptionModel = llvm::ExceptionHandling::DwarfCFI;
 466   if (LangOpts.WasmExceptions)
 467     Options.ExceptionModel = llvm::ExceptionHandling::Wasm;
 468
 469   Options.NoInfsFPMath = CodeGenOpts.NoInfsFPMath;
 470   Options.NoNaNsFPMath = CodeGenOpts.NoNaNsFPMath;
 471   Options.NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS;
 472   Options.UnsafeFPMath = CodeGenOpts.UnsafeFPMath;
 473   Options.StackAlignmentOverride = CodeGenOpts.StackAlignment;
 474   Options.FunctionSections = CodeGenOpts.FunctionSections;
 475   Options.DataSections = CodeGenOpts.DataSections;
 476   Options.UniqueSectionNames = CodeGenOpts.UniqueSectionNames;
 477   Options.TLSSize = CodeGenOpts.TLSSize;
 478   Options.EmulatedTLS = CodeGenOpts.EmulatedTLS;
 479   Options.ExplicitEmulatedTLS = CodeGenOpts.ExplicitEmulatedTLS;
 480   Options.DebuggerTuning = CodeGenOpts.getDebuggerTuning();
 481   Options.EmitStackSizeSection = CodeGenOpts.StackSizeSection;
 482   Options.EmitAddrsig = CodeGenOpts.Addrsig;
 483   Options.EnableDebugEntryValues = CodeGenOpts.EnableDebugEntryValues;
 484   Options.ForceDwarfFrameSection = CodeGenOpts.ForceDwarfFrameSection;
 485
 486   Options.MCOptions.SplitDwarfFile = CodeGenOpts.SplitDwarfFile;
 487   Options.MCOptions.MCRelaxAll = CodeGenOpts.RelaxAll;
 488   Options.MCOptions.MCSaveTempLabels = CodeGenOpts.SaveTempLabels;
 489   Options.MCOptions.MCUseDwarfDirectory = !CodeGenOpts.NoDwarfDirectoryAsm;
 490   Options.MCOptions.MCNoExecStack = CodeGenOpts.NoExecStack;
 491   Options.MCOptions.MCIncrementalLinkerCompatible =
 492       CodeGenOpts.IncrementalLinkerCompatible;
 493   Options.MCOptions.MCFatalWarnings = CodeGenOpts.FatalWarnings;
 494   Options.MCOptions.MCNoWarn = CodeGenOpts.NoWarn;
 495   Options.MCOptions.AsmVerbose = CodeGenOpts.AsmVerbose;
 496   Options.MCOptions.PreserveAsmComments = CodeGenOpts.PreserveAsmComments;
 497   Options.MCOptions.ABIName = TargetOpts.ABI;
 498   for (const auto &Entry : HSOpts.UserEntries)
 499     if (!Entry.IsFramework &&
 500         (Entry.Group == frontend::IncludeDirGroup::Quoted ||
 501          Entry.Group == frontend::IncludeDirGroup::Angled ||
 502          Entry.Group == frontend::IncludeDirGroup::System))
 503       Options.MCOptions.IASSearchPaths.push_back(
 504           Entry.IgnoreSysRoot ? Entry.Path : HSOpts.Sysroot + Entry.Path);
 505 }
 506 static Optional<GCOVOptions> getGCOVOptions(const CodeGenOptions &CodeGenOpts) {
 507   if (CodeGenOpts.DisableGCov)
 508     return None;
 509   if (!CodeGenOpts.EmitGcovArcs && !CodeGenOpts.EmitGcovNotes)
 510     return None;
 511   // Not using 'GCOVOptions::getDefault' allows us to avoid exiting if
 512   // LLVM's -default-gcov-version flag is set to something invalid.
 513   GCOVOptions Options;
 514   Options.EmitNotes = CodeGenOpts.EmitGcovNotes;
 515   Options.EmitData = CodeGenOpts.EmitGcovArcs;
 516   llvm::copy(CodeGenOpts.CoverageVersion, std::begin(Options.Version));
 517   Options.UseCfgChecksum = CodeGenOpts.CoverageExtraChecksum;
 518   Options.NoRedZone = CodeGenOpts.DisableRedZone;
 519   Options.FunctionNamesInData = !CodeGenOpts.CoverageNoFunctionNamesInData;
 520   Options.Filter = CodeGenOpts.ProfileFilterFiles;
 521   Options.Exclude = CodeGenOpts.ProfileExcludeFiles;
 522   Options.ExitBlockBeforeBody = CodeGenOpts.CoverageExitBlockBeforeBody;
 523   return Options;
 524 }
 525
 526 static Optional<InstrProfOptions>
 527 getInstrProfOptions(const CodeGenOptions &CodeGenOpts,
 528                     const LangOptions &LangOpts) {
 529   if (!CodeGenOpts.hasProfileClangInstr())
 530     return None;
 531   InstrProfOptions Options;
 532   Options.NoRedZone = CodeGenOpts.DisableRedZone;
 533   Options.InstrProfileOutput = CodeGenOpts.InstrProfileOutput;
 534
 535   // TODO: Surface the option to emit atomic profile counter increments at
 536   // the driver level.
 537   Options.Atomic = LangOpts.Sanitize.has(SanitizerKind::Thread);
 538   return Options;
 539 }
 540
 541 void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
 542                                       legacy::FunctionPassManager &FPM) {
 543   // Handle disabling of all LLVM passes, where we want to preserve the
 544   // internal module before any optimization.
 545   if (CodeGenOpts.DisableLLVMPasses)
 546     return;
 547
 548   // Figure out TargetLibraryInfo.  This needs to be added to MPM and FPM
 549   // manually (and not via PMBuilder), since some passes (eg. InstrProfiling)
 550   // are inserted before PMBuilder ones - they'd get the default-constructed
 551   // TLI with an unknown target otherwise.
 552   Triple TargetTriple(TheModule->getTargetTriple());
 553   std::unique_ptr<TargetLibraryInfoImpl> TLII(
 554       createTLII(TargetTriple, CodeGenOpts));
 555
 556   PassManagerBuilderWrapper PMBuilder(TargetTriple, CodeGenOpts, LangOpts);
 557
 558   // At O0 and O1 we only run the always inliner which is more efficient. At
 559   // higher optimization levels we run the normal inliner.
 560   if (CodeGenOpts.OptimizationLevel <= 1) {
 561     bool InsertLifetimeIntrinsics = (CodeGenOpts.OptimizationLevel != 0 &&
 562                                      !CodeGenOpts.DisableLifetimeMarkers);
 563     PMBuilder.Inliner = createAlwaysInlinerLegacyPass(InsertLifetimeIntrinsics);
 564   } else {
 565     // We do not want to inline hot callsites for SamplePGO module-summary build
 566     // because profile annotation will happen again in ThinLTO backend, and we
 567     // want the IR of the hot path to match the profile.
 568     PMBuilder.Inliner = createFunctionInliningPass(
 569         CodeGenOpts.OptimizationLevel, CodeGenOpts.OptimizeSize,
 570         (!CodeGenOpts.SampleProfileFile.empty() &&
 571          CodeGenOpts.PrepareForThinLTO));
 572   }
 573
 574   PMBuilder.OptLevel = CodeGenOpts.OptimizationLevel;
 575   PMBuilder.SizeLevel = CodeGenOpts.OptimizeSize;
 576   PMBuilder.SLPVectorize = CodeGenOpts.VectorizeSLP;
 577   PMBuilder.LoopVectorize = CodeGenOpts.VectorizeLoop;
 578
 579   PMBuilder.DisableUnrollLoops = !CodeGenOpts.UnrollLoops;
 580   // Loop interleaving in the loop vectorizer has historically been set to be
 581   // enabled when loop unrolling is enabled.
 582   PMBuilder.LoopsInterleaved = CodeGenOpts.UnrollLoops;
 583   PMBuilder.MergeFunctions = CodeGenOpts.MergeFunctions;
 584   PMBuilder.PrepareForThinLTO = CodeGenOpts.PrepareForThinLTO;
 585   PMBuilder.PrepareForLTO = CodeGenOpts.PrepareForLTO;
 586   PMBuilder.RerollLoops = CodeGenOpts.RerollLoops;
 587
 588   MPM.add(new TargetLibraryInfoWrapperPass(*TLII));
 589
 590   if (TM)
 591     TM->adjustPassManager(PMBuilder);
 592
 593   if (CodeGenOpts.DebugInfoForProfiling ||
 594       !CodeGenOpts.SampleProfileFile.empty())
 595     PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
 596                            addAddDiscriminatorsPass);
 597
 598   // In ObjC ARC mode, add the main ARC optimization passes.
 599   if (LangOpts.ObjCAutoRefCount) {
 600     PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
 601                            addObjCARCExpandPass);
 602     PMBuilder.addExtension(PassManagerBuilder::EP_ModuleOptimizerEarly,
 603                            addObjCARCAPElimPass);
 604     PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
 605                            addObjCARCOptPass);
 606   }
 607
 608   if (LangOpts.Coroutines)
 609     addCoroutinePassesToExtensionPoints(PMBuilder);
 610
 611   if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds)) {
 612     PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
 613                            addBoundsCheckingPass);
 614     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 615                            addBoundsCheckingPass);
 616   }
 617
 618   if (CodeGenOpts.SanitizeCoverageType ||
 619       CodeGenOpts.SanitizeCoverageIndirectCalls ||
 620       CodeGenOpts.SanitizeCoverageTraceCmp) {
 621     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 622                            addSanitizerCoveragePass);
 623     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 624                            addSanitizerCoveragePass);
 625   }
 626
 627   if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
 628     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 629                            addAddressSanitizerPasses);
 630     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 631                            addAddressSanitizerPasses);
 632   }
 633
 634   if (LangOpts.Sanitize.has(SanitizerKind::KernelAddress)) {
 635     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 636                            addKernelAddressSanitizerPasses);
 637     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 638                            addKernelAddressSanitizerPasses);
 639   }
 640
 641   if (LangOpts.Sanitize.has(SanitizerKind::HWAddress)) {
 642     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 643                            addHWAddressSanitizerPasses);
 644     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 645                            addHWAddressSanitizerPasses);
 646   }
 647
 648   if (LangOpts.Sanitize.has(SanitizerKind::KernelHWAddress)) {
 649     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 650                            addKernelHWAddressSanitizerPasses);
 651     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 652                            addKernelHWAddressSanitizerPasses);
 653   }
 654
 655   if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
 656     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 657                            addMemorySanitizerPass);
 658     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 659                            addMemorySanitizerPass);
 660   }
 661
 662   if (LangOpts.Sanitize.has(SanitizerKind::KernelMemory)) {
 663     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 664                            addKernelMemorySanitizerPass);
 665     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 666                            addKernelMemorySanitizerPass);
 667   }
 668
 669   if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
 670     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 671                            addThreadSanitizerPass);
 672     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 673                            addThreadSanitizerPass);
 674   }
 675
 676   if (LangOpts.Sanitize.has(SanitizerKind::DataFlow)) {
 677     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 678                            addDataFlowSanitizerPass);
 679     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 680                            addDataFlowSanitizerPass);
 681   }
 682
 683   // Set up the per-function pass manager.
 684   FPM.add(new TargetLibraryInfoWrapperPass(*TLII));
 685   if (CodeGenOpts.VerifyModule)
 686     FPM.add(createVerifierPass());
 687
 688   // Set up the per-module pass manager.
 689   if (!CodeGenOpts.RewriteMapFiles.empty())
 690     addSymbolRewriterPass(CodeGenOpts, &MPM);
 691
 692   if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts)) {
 693     MPM.add(createGCOVProfilerPass(*Options));
 694     if (CodeGenOpts.getDebugInfo() == codegenoptions::NoDebugInfo)
 695       MPM.add(createStripSymbolsPass(true));
 696   }
 697
 698   if (Optional<InstrProfOptions> Options =
 699           getInstrProfOptions(CodeGenOpts, LangOpts))
 700     MPM.add(createInstrProfilingLegacyPass(*Options, false));
 701
 702   bool hasIRInstr = false;
 703   if (CodeGenOpts.hasProfileIRInstr()) {
 704     PMBuilder.EnablePGOInstrGen = true;
 705     hasIRInstr = true;
 706   }
 707   if (CodeGenOpts.hasProfileCSIRInstr()) {
 708     assert(!CodeGenOpts.hasProfileCSIRUse() &&
 709            "Cannot have both CSProfileUse pass and CSProfileGen pass at the "
 710            "same time");
 711     assert(!hasIRInstr &&
 712            "Cannot have both ProfileGen pass and CSProfileGen pass at the "
 713            "same time");
 714     PMBuilder.EnablePGOCSInstrGen = true;
 715     hasIRInstr = true;
 716   }
 717   if (hasIRInstr) {
 718     if (!CodeGenOpts.InstrProfileOutput.empty())
 719       PMBuilder.PGOInstrGen = CodeGenOpts.InstrProfileOutput;
 720     else
 721       PMBuilder.PGOInstrGen = DefaultProfileGenName;
 722   }
 723   if (CodeGenOpts.hasProfileIRUse()) {
 724     PMBuilder.PGOInstrUse = CodeGenOpts.ProfileInstrumentUsePath;
 725     PMBuilder.EnablePGOCSInstrUse = CodeGenOpts.hasProfileCSIRUse();
 726   }
 727
 728   if (!CodeGenOpts.SampleProfileFile.empty())
 729     PMBuilder.PGOSampleUse = CodeGenOpts.SampleProfileFile;
 730
 731   PMBuilder.populateFunctionPassManager(FPM);
 732   PMBuilder.populateModulePassManager(MPM);
 733 }
 734
 735 static void setCommandLineOpts(const CodeGenOptions &CodeGenOpts) {
 736   SmallVector<const char *, 16> BackendArgs;
 737   BackendArgs.push_back("clang"); // Fake program name.
 738   if (!CodeGenOpts.DebugPass.empty()) {
 739     BackendArgs.push_back("-debug-pass");
 740     BackendArgs.push_back(CodeGenOpts.DebugPass.c_str());
 741   }
 742   if (!CodeGenOpts.LimitFloatPrecision.empty()) {
 743     BackendArgs.push_back("-limit-float-precision");
 744     BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
 745   }
 746   BackendArgs.push_back(nullptr);
 747   llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
 748                                     BackendArgs.data());
 749 }
 750
 751 void EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
 752   // Create the TargetMachine for generating code.
 753   std::string Error;
 754   std::string Triple = TheModule->getTargetTriple();
 755   const llvm::Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error);
 756   if (!TheTarget) {
 757     if (MustCreateTM)
 758       Diags.Report(diag::err_fe_unable_to_create_target) << Error;
 759     return;
 760   }
 761
 762   Optional<llvm::CodeModel::Model> CM = getCodeModel(CodeGenOpts);
 763   std::string FeaturesStr =
 764       llvm::join(TargetOpts.Features.begin(), TargetOpts.Features.end(), ",");
 765   llvm::Reloc::Model RM = CodeGenOpts.RelocationModel;
 766   CodeGenOpt::Level OptLevel = getCGOptLevel(CodeGenOpts);
 767
 768   llvm::TargetOptions Options;
 769   initTargetOptions(Options, CodeGenOpts, TargetOpts, LangOpts, HSOpts);
 770   TM.reset(TheTarget->createTargetMachine(Triple, TargetOpts.CPU, FeaturesStr,
 771                                           Options, RM, CM, OptLevel));
 772 }
 773
 774 bool EmitAssemblyHelper::AddEmitPasses(legacy::PassManager &CodeGenPasses,
 775                                        BackendAction Action,
 776                                        raw_pwrite_stream &OS,
 777                                        raw_pwrite_stream *DwoOS) {
 778   // Add LibraryInfo.
 779   llvm::Triple TargetTriple(TheModule->getTargetTriple());
 780   std::unique_ptr<TargetLibraryInfoImpl> TLII(
 781       createTLII(TargetTriple, CodeGenOpts));
 782   CodeGenPasses.add(new TargetLibraryInfoWrapperPass(*TLII));
 783
 784   // Normal mode, emit a .s or .o file by running the code generator. Note,
 785   // this also adds codegenerator level optimization passes.
 786   CodeGenFileType CGFT = getCodeGenFileType(Action);
 787
 788   // Add ObjC ARC final-cleanup optimizations. This is done as part of the
 789   // "codegen" passes so that it isn't run multiple times when there is
 790   // inlining happening.
 791   if (CodeGenOpts.OptimizationLevel > 0)
 792     CodeGenPasses.add(createObjCARCContractPass());
 793
 794   if (TM->addPassesToEmitFile(CodeGenPasses, OS, DwoOS, CGFT,
 795                               /*DisableVerify=*/!CodeGenOpts.VerifyModule)) {
 796     Diags.Report(diag::err_fe_unable_to_interface_with_target);
 797     return false;
 798   }
 799
 800   return true;
 801 }
 802
 803 void EmitAssemblyHelper::EmitAssembly(BackendAction Action,
 804                                       std::unique_ptr<raw_pwrite_stream> OS) {
 805   TimeRegion Region(FrontendTimesIsEnabled ? &CodeGenerationTime : nullptr);
 806
 807   setCommandLineOpts(CodeGenOpts);
 808
 809   bool UsesCodeGen = (Action != Backend_EmitNothing &&
 810                       Action != Backend_EmitBC &&
 811                       Action != Backend_EmitLL);
 812   CreateTargetMachine(UsesCodeGen);
 813
 814   if (UsesCodeGen && !TM)
 815     return;
 816   if (TM)
 817     TheModule->setDataLayout(TM->createDataLayout());
 818
 819   legacy::PassManager PerModulePasses;
 820   PerModulePasses.add(
 821       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
 822
 823   legacy::FunctionPassManager PerFunctionPasses(TheModule);
 824   PerFunctionPasses.add(
 825       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
 826
 827   CreatePasses(PerModulePasses, PerFunctionPasses);
 828
 829   legacy::PassManager CodeGenPasses;
 830   CodeGenPasses.add(
 831       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
 832
 833   std::unique_ptr<llvm::ToolOutputFile> ThinLinkOS, DwoOS;
 834
 835   switch (Action) {
 836   case Backend_EmitNothing:
 837     break;
 838
 839   case Backend_EmitBC:
 840     if (CodeGenOpts.PrepareForThinLTO && !CodeGenOpts.DisableLLVMPasses) {
 841       if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
 842         ThinLinkOS = openOutputFile(CodeGenOpts.ThinLinkBitcodeFile);
 843         if (!ThinLinkOS)
 844           return;
 845       }
 846       TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
 847                                CodeGenOpts.EnableSplitLTOUnit);
 848       PerModulePasses.add(createWriteThinLTOBitcodePass(
 849           *OS, ThinLinkOS ? &ThinLinkOS->os() : nullptr));
 850     } else {
 851       // Emit a module summary by default for Regular LTO except for ld64
 852       // targets
 853       bool EmitLTOSummary =
 854           (CodeGenOpts.PrepareForLTO &&
 855            !CodeGenOpts.DisableLLVMPasses &&
 856            llvm::Triple(TheModule->getTargetTriple()).getVendor() !=
 857                llvm::Triple::Apple);
 858       if (EmitLTOSummary) {
 859         if (!TheModule->getModuleFlag("ThinLTO"))
 860           TheModule->addModuleFlag(Module::Error, "ThinLTO", uint32_t(0));
 861         TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
 862                                  uint32_t(1));
 863       }
 864
 865       PerModulePasses.add(createBitcodeWriterPass(
 866           *OS, CodeGenOpts.EmitLLVMUseLists, EmitLTOSummary));
 867     }
 868     break;
 869
 870   case Backend_EmitLL:
 871     PerModulePasses.add(
 872         createPrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
 873     break;
 874
 875   default:
 876     if (!CodeGenOpts.SplitDwarfOutput.empty()) {
 877       DwoOS = openOutputFile(CodeGenOpts.SplitDwarfOutput);
 878       if (!DwoOS)
 879         return;
 880     }
 881     if (!AddEmitPasses(CodeGenPasses, Action, *OS,
 882                        DwoOS ? &DwoOS->os() : nullptr))
 883       return;
 884   }
 885
 886   // Before executing passes, print the final values of the LLVM options.
 887   cl::PrintOptionValues();
 888
 889   // Run passes. For now we do all passes at once, but eventually we
 890   // would like to have the option of streaming code generation.
 891
 892   {
 893     PrettyStackTraceString CrashInfo("Per-function optimization");
 894     llvm::TimeTraceScope TimeScope("PerFunctionPasses");
 895
 896     PerFunctionPasses.doInitialization();
 897     for (Function &F : *TheModule)
 898       if (!F.isDeclaration())
 899         PerFunctionPasses.run(F);
 900     PerFunctionPasses.doFinalization();
 901   }
 902
 903   {
 904     PrettyStackTraceString CrashInfo("Per-module optimization passes");
 905     llvm::TimeTraceScope TimeScope("PerModulePasses");
 906     PerModulePasses.run(*TheModule);
 907   }
 908
 909   {
 910     PrettyStackTraceString CrashInfo("Code generation");
 911     llvm::TimeTraceScope TimeScope("CodeGenPasses");
 912     CodeGenPasses.run(*TheModule);
 913   }
 914
 915   if (ThinLinkOS)
 916     ThinLinkOS->keep();
 917   if (DwoOS)
 918     DwoOS->keep();
 919 }
 920
 921 static PassBuilder::OptimizationLevel mapToLevel(const CodeGenOptions &Opts) {
 922   switch (Opts.OptimizationLevel) {
 923   default:
 924     llvm_unreachable("Invalid optimization level!");
 925
 926   case 1:
 927     return PassBuilder::O1;
 928
 929   case 2:
 930     switch (Opts.OptimizeSize) {
 931     default:
 932       llvm_unreachable("Invalid optimization level for size!");
 933
 934     case 0:
 935       return PassBuilder::O2;
 936
 937     case 1:
 938       return PassBuilder::Os;
 939
 940     case 2:
 941       return PassBuilder::Oz;
 942     }
 943
 944   case 3:
 945     return PassBuilder::O3;
 946   }
 947 }
 948
 949 static void addSanitizersAtO0(ModulePassManager &MPM,
 950                               const Triple &TargetTriple,
 951                               const LangOptions &LangOpts,
 952                               const CodeGenOptions &CodeGenOpts) {
 953   auto ASanPass = [&](SanitizerMask Mask, bool CompileKernel) {
 954     MPM.addPass(RequireAnalysisPass<ASanGlobalsMetadataAnalysis, Module>());
 955     bool Recover = CodeGenOpts.SanitizeRecover.has(Mask);
 956     MPM.addPass(createModuleToFunctionPassAdaptor(AddressSanitizerPass(
 957         CompileKernel, Recover, CodeGenOpts.SanitizeAddressUseAfterScope)));
 958     bool ModuleUseAfterScope = asanUseGlobalsGC(TargetTriple, CodeGenOpts);
 959     MPM.addPass(
 960         ModuleAddressSanitizerPass(CompileKernel, Recover, ModuleUseAfterScope,
 961                                    CodeGenOpts.SanitizeAddressUseOdrIndicator));
 962   };
 963
 964   if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
 965     ASanPass(SanitizerKind::Address, /*CompileKernel=*/false);
 966   }
 967
 968   if (LangOpts.Sanitize.has(SanitizerKind::KernelAddress)) {
 969     ASanPass(SanitizerKind::KernelAddress, /*CompileKernel=*/true);
 970   }
 971
 972   if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
 973     MPM.addPass(MemorySanitizerPass({}));
 974     MPM.addPass(createModuleToFunctionPassAdaptor(MemorySanitizerPass({})));
 975   }
 976
 977   if (LangOpts.Sanitize.has(SanitizerKind::KernelMemory)) {
 978     MPM.addPass(createModuleToFunctionPassAdaptor(
 979         MemorySanitizerPass({0, false, /*Kernel=*/true})));
 980   }
 981
 982   if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
 983     MPM.addPass(ThreadSanitizerPass());
 984     MPM.addPass(createModuleToFunctionPassAdaptor(ThreadSanitizerPass()));
 985   }
 986 }
 987
 988 /// A clean version of `EmitAssembly` that uses the new pass manager.
 989 ///
 990 /// Not all features are currently supported in this system, but where
 991 /// necessary it falls back to the legacy pass manager to at least provide
 992 /// basic functionality.
 993 ///
 994 /// This API is planned to have its functionality finished and then to replace
 995 /// `EmitAssembly` at some point in the future when the default switches.
 996 void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
 997     BackendAction Action, std::unique_ptr<raw_pwrite_stream> OS) {
 998   TimeRegion Region(FrontendTimesIsEnabled ? &CodeGenerationTime : nullptr);
 999   setCommandLineOpts(CodeGenOpts);
1000
1001   bool RequiresCodeGen = (Action != Backend_EmitNothing &&
1002                           Action != Backend_EmitBC &&
1003                           Action != Backend_EmitLL);
1004   CreateTargetMachine(RequiresCodeGen);
1005
1006   if (RequiresCodeGen && !TM)
1007     return;
1008   if (TM)
1009     TheModule->setDataLayout(TM->createDataLayout());
1010
1011   Optional<PGOOptions> PGOOpt;
1012
1013   if (CodeGenOpts.hasProfileIRInstr())
1014     // -fprofile-generate.
1015     PGOOpt = PGOOptions(CodeGenOpts.InstrProfileOutput.empty()
1016                             ? DefaultProfileGenName
1017                             : CodeGenOpts.InstrProfileOutput,
1018                         "", "", PGOOptions::IRInstr, PGOOptions::NoCSAction,
1019                         CodeGenOpts.DebugInfoForProfiling);
1020   else if (CodeGenOpts.hasProfileIRUse()) {
1021     // -fprofile-use.
1022     auto CSAction = CodeGenOpts.hasProfileCSIRUse() ? PGOOptions::CSIRUse
1023                                                     : PGOOptions::NoCSAction;
1024     PGOOpt = PGOOptions(CodeGenOpts.ProfileInstrumentUsePath, "",
1025                         CodeGenOpts.ProfileRemappingFile, PGOOptions::IRUse,
1026                         CSAction, CodeGenOpts.DebugInfoForProfiling);
1027   } else if (!CodeGenOpts.SampleProfileFile.empty())
1028     // -fprofile-sample-use
1029     PGOOpt =
1030         PGOOptions(CodeGenOpts.SampleProfileFile, "",
1031                    CodeGenOpts.ProfileRemappingFile, PGOOptions::SampleUse,
1032                    PGOOptions::NoCSAction, CodeGenOpts.DebugInfoForProfiling);
1033   else if (CodeGenOpts.DebugInfoForProfiling)
1034     // -fdebug-info-for-profiling
1035     PGOOpt = PGOOptions("", "", "", PGOOptions::NoAction,
1036                         PGOOptions::NoCSAction, true);
1037
1038   // Check to see if we want to generate a CS profile.
1039   if (CodeGenOpts.hasProfileCSIRInstr()) {
1040     assert(!CodeGenOpts.hasProfileCSIRUse() &&
1041            "Cannot have both CSProfileUse pass and CSProfileGen pass at "
1042            "the same time");
1043     if (PGOOpt.hasValue()) {
1044       assert(PGOOpt->Action != PGOOptions::IRInstr &&
1045              PGOOpt->Action != PGOOptions::SampleUse &&
1046              "Cannot run CSProfileGen pass with ProfileGen or SampleUse "
1047              " pass");
1048       PGOOpt->CSProfileGenFile = CodeGenOpts.InstrProfileOutput.empty()
1049                                      ? DefaultProfileGenName
1050                                      : CodeGenOpts.InstrProfileOutput;
1051       PGOOpt->CSAction = PGOOptions::CSIRInstr;
1052     } else
1053       PGOOpt = PGOOptions("",
1054                           CodeGenOpts.InstrProfileOutput.empty()
1055                               ? DefaultProfileGenName
1056                               : CodeGenOpts.InstrProfileOutput,
1057                           "", PGOOptions::NoAction, PGOOptions::CSIRInstr,
1058                           CodeGenOpts.DebugInfoForProfiling);
1059   }
1060
1061   PipelineTuningOptions PTO;
1062   PTO.LoopUnrolling = CodeGenOpts.UnrollLoops;
1063   // For historical reasons, loop interleaving is set to mirror setting for loop
1064   // unrolling.
1065   PTO.LoopInterleaving = CodeGenOpts.UnrollLoops;
1066   PTO.LoopVectorization = CodeGenOpts.VectorizeLoop;
1067   PTO.SLPVectorization = CodeGenOpts.VectorizeSLP;
1068
1069   PassInstrumentationCallbacks PIC;
1070   StandardInstrumentations SI;
1071   SI.registerCallbacks(PIC);
1072   PassBuilder PB(TM.get(), PTO, PGOOpt, &PIC);
1073
1074   // Attempt to load pass plugins and register their callbacks with PB.
1075   for (auto &PluginFN : CodeGenOpts.PassPlugins) {
1076     auto PassPlugin = PassPlugin::Load(PluginFN);
1077     if (PassPlugin) {
1078       PassPlugin->registerPassBuilderCallbacks(PB);
1079     } else {
1080       Diags.Report(diag::err_fe_unable_to_load_plugin)
1081           << PluginFN << toString(PassPlugin.takeError());
1082     }
1083   }
1084 #define HANDLE_EXTENSION(Ext)                                                  \
1085   get##Ext##PluginInfo().RegisterPassBuilderCallbacks(PB);
1086 #include "llvm/Support/Extension.def"
1087
1088   LoopAnalysisManager LAM(CodeGenOpts.DebugPassManager);
1089   FunctionAnalysisManager FAM(CodeGenOpts.DebugPassManager);
1090   CGSCCAnalysisManager CGAM(CodeGenOpts.DebugPassManager);
1091   ModuleAnalysisManager MAM(CodeGenOpts.DebugPassManager);
1092
1093   // Register the AA manager first so that our version is the one used.
1094   FAM.registerPass([&] { return PB.buildDefaultAAPipeline(); });
1095
1096   // Register the target library analysis directly and give it a customized
1097   // preset TLI.
1098   Triple TargetTriple(TheModule->getTargetTriple());
1099   std::unique_ptr<TargetLibraryInfoImpl> TLII(
1100       createTLII(TargetTriple, CodeGenOpts));
1101   FAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
1102
1103   // Register all the basic analyses with the managers.
1104   PB.registerModuleAnalyses(MAM);
1105   PB.registerCGSCCAnalyses(CGAM);
1106   PB.registerFunctionAnalyses(FAM);
1107   PB.registerLoopAnalyses(LAM);
1108   PB.crossRegisterProxies(LAM, FAM, CGAM, MAM);
1109
1110   ModulePassManager MPM(CodeGenOpts.DebugPassManager);
1111
1112   if (!CodeGenOpts.DisableLLVMPasses) {
1113     bool IsThinLTO = CodeGenOpts.PrepareForThinLTO;
1114     bool IsLTO = CodeGenOpts.PrepareForLTO;
1115
1116     if (CodeGenOpts.OptimizationLevel == 0) {
1117       if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts))
1118         MPM.addPass(GCOVProfilerPass(*Options));
1119       if (Optional<InstrProfOptions> Options =
1120               getInstrProfOptions(CodeGenOpts, LangOpts))
1121         MPM.addPass(InstrProfiling(*Options, false));
1122
1123       // Build a minimal pipeline based on the semantics required by Clang,
1124       // which is just that always inlining occurs. Further, disable generating
1125       // lifetime intrinsics to avoid enabling further optimizations during
1126       // code generation.
1127       MPM.addPass(AlwaysInlinerPass(/*InsertLifetimeIntrinsics=*/false));
1128
1129       // At -O0, we can still do PGO. Add all the requested passes for
1130       // instrumentation PGO, if requested.
1131       if (PGOOpt && (PGOOpt->Action == PGOOptions::IRInstr ||
1132                      PGOOpt->Action == PGOOptions::IRUse))
1133         PB.addPGOInstrPassesForO0(
1134             MPM, CodeGenOpts.DebugPassManager,
1135             /* RunProfileGen */ (PGOOpt->Action == PGOOptions::IRInstr),
1136             /* IsCS */ false, PGOOpt->ProfileFile,
1137             PGOOpt->ProfileRemappingFile);
1138
1139       // At -O0 we directly run necessary sanitizer passes.
1140       if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
1141         MPM.addPass(createModuleToFunctionPassAdaptor(BoundsCheckingPass()));
1142
1143       // Lastly, add semantically necessary passes for LTO.
1144       if (IsLTO || IsThinLTO) {
1145         MPM.addPass(CanonicalizeAliasesPass());
1146         MPM.addPass(NameAnonGlobalPass());
1147       }
1148     } else {
1149       // Map our optimization levels into one of the distinct levels used to
1150       // configure the pipeline.
1151       PassBuilder::OptimizationLevel Level = mapToLevel(CodeGenOpts);
1152
1153       PB.registerPipelineStartEPCallback([](ModulePassManager &MPM) {
1154         MPM.addPass(createModuleToFunctionPassAdaptor(
1155             EntryExitInstrumenterPass(/*PostInlining=*/false)));
1156       });
1157
1158       // Register callbacks to schedule sanitizer passes at the appropriate part of
1159       // the pipeline.
1160       // FIXME: either handle asan/the remaining sanitizers or error out
1161       if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
1162         PB.registerScalarOptimizerLateEPCallback(
1163             [](FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
1164               FPM.addPass(BoundsCheckingPass());
1165             });
1166       if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
1167         PB.registerPipelineStartEPCallback([](ModulePassManager &MPM) {
1168           MPM.addPass(MemorySanitizerPass({}));
1169         });
1170         PB.registerOptimizerLastEPCallback(
1171             [](FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
1172               FPM.addPass(MemorySanitizerPass({}));
1173             });
1174       }
1175       if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
1176         PB.registerPipelineStartEPCallback(
1177             [](ModulePassManager &MPM) { MPM.addPass(ThreadSanitizerPass()); });
1178         PB.registerOptimizerLastEPCallback(
1179             [](FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
1180               FPM.addPass(ThreadSanitizerPass());
1181             });
1182       }
1183       if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
1184         PB.registerPipelineStartEPCallback([&](ModulePassManager &MPM) {
1185           MPM.addPass(
1186               RequireAnalysisPass<ASanGlobalsMetadataAnalysis, Module>());
1187         });
1188         bool Recover = CodeGenOpts.SanitizeRecover.has(SanitizerKind::Address);
1189         bool UseAfterScope = CodeGenOpts.SanitizeAddressUseAfterScope;
1190         PB.registerOptimizerLastEPCallback(
1191             [Recover, UseAfterScope](FunctionPassManager &FPM,
1192                                      PassBuilder::OptimizationLevel Level) {
1193               FPM.addPass(AddressSanitizerPass(
1194                   /*CompileKernel=*/false, Recover, UseAfterScope));
1195             });
1196         bool ModuleUseAfterScope = asanUseGlobalsGC(TargetTriple, CodeGenOpts);
1197         bool UseOdrIndicator = CodeGenOpts.SanitizeAddressUseOdrIndicator;
1198         PB.registerPipelineStartEPCallback(
1199             [Recover, ModuleUseAfterScope,
1200              UseOdrIndicator](ModulePassManager &MPM) {
1201               MPM.addPass(ModuleAddressSanitizerPass(
1202                   /*CompileKernel=*/false, Recover, ModuleUseAfterScope,
1203                   UseOdrIndicator));
1204             });
1205       }
1206       if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts))
1207         PB.registerPipelineStartEPCallback([Options](ModulePassManager &MPM) {
1208           MPM.addPass(GCOVProfilerPass(*Options));
1209         });
1210       if (Optional<InstrProfOptions> Options =
1211               getInstrProfOptions(CodeGenOpts, LangOpts))
1212         PB.registerPipelineStartEPCallback([Options](ModulePassManager &MPM) {
1213           MPM.addPass(InstrProfiling(*Options, false));
1214         });
1215
1216       if (IsThinLTO) {
1217         MPM = PB.buildThinLTOPreLinkDefaultPipeline(
1218             Level, CodeGenOpts.DebugPassManager);
1219         MPM.addPass(CanonicalizeAliasesPass());
1220         MPM.addPass(NameAnonGlobalPass());
1221       } else if (IsLTO) {
1222         MPM = PB.buildLTOPreLinkDefaultPipeline(Level,
1223                                                 CodeGenOpts.DebugPassManager);
1224         MPM.addPass(CanonicalizeAliasesPass());
1225         MPM.addPass(NameAnonGlobalPass());
1226       } else {
1227         MPM = PB.buildPerModuleDefaultPipeline(Level,
1228                                                CodeGenOpts.DebugPassManager);
1229       }
1230     }
1231
1232     if (CodeGenOpts.SanitizeCoverageType ||
1233         CodeGenOpts.SanitizeCoverageIndirectCalls ||
1234         CodeGenOpts.SanitizeCoverageTraceCmp) {
1235       auto SancovOpts = getSancovOptsFromCGOpts(CodeGenOpts);
1236       MPM.addPass(ModuleSanitizerCoveragePass(SancovOpts));
1237     }
1238
1239     if (LangOpts.Sanitize.has(SanitizerKind::HWAddress)) {
1240       bool Recover = CodeGenOpts.SanitizeRecover.has(SanitizerKind::HWAddress);
1241       MPM.addPass(HWAddressSanitizerPass(
1242           /*CompileKernel=*/false, Recover));
1243     }
1244     if (LangOpts.Sanitize.has(SanitizerKind::KernelHWAddress)) {
1245       MPM.addPass(HWAddressSanitizerPass(
1246           /*CompileKernel=*/true, /*Recover=*/true));
1247     }
1248
1249     if (CodeGenOpts.OptimizationLevel == 0) {
1250       addSanitizersAtO0(MPM, TargetTriple, LangOpts, CodeGenOpts);
1251     }
1252   }
1253
1254   // FIXME: We still use the legacy pass manager to do code generation. We
1255   // create that pass manager here and use it as needed below.
1256   legacy::PassManager CodeGenPasses;
1257   bool NeedCodeGen = false;
1258   std::unique_ptr<llvm::ToolOutputFile> ThinLinkOS, DwoOS;
1259
1260   // Append any output we need to the pass manager.
1261   switch (Action) {
1262   case Backend_EmitNothing:
1263     break;
1264
1265   case Backend_EmitBC:
1266     if (CodeGenOpts.PrepareForThinLTO && !CodeGenOpts.DisableLLVMPasses) {
1267       if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
1268         ThinLinkOS = openOutputFile(CodeGenOpts.ThinLinkBitcodeFile);
1269         if (!ThinLinkOS)
1270           return;
1271       }
1272       TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
1273                                CodeGenOpts.EnableSplitLTOUnit);
1274       MPM.addPass(ThinLTOBitcodeWriterPass(*OS, ThinLinkOS ? &ThinLinkOS->os()
1275                                                            : nullptr));
1276     } else {
1277       // Emit a module summary by default for Regular LTO except for ld64
1278       // targets
1279       bool EmitLTOSummary =
1280           (CodeGenOpts.PrepareForLTO &&
1281            !CodeGenOpts.DisableLLVMPasses &&
1282            llvm::Triple(TheModule->getTargetTriple()).getVendor() !=
1283                llvm::Triple::Apple);
1284       if (EmitLTOSummary) {
1285         if (!TheModule->getModuleFlag("ThinLTO"))
1286           TheModule->addModuleFlag(Module::Error, "ThinLTO", uint32_t(0));
1287         TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
1288                                  uint32_t(1));
1289       }
1290       MPM.addPass(
1291           BitcodeWriterPass(*OS, CodeGenOpts.EmitLLVMUseLists, EmitLTOSummary));
1292     }
1293     break;
1294
1295   case Backend_EmitLL:
1296     MPM.addPass(PrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
1297     break;
1298
1299   case Backend_EmitAssembly:
1300   case Backend_EmitMCNull:
1301   case Backend_EmitObj:
1302     NeedCodeGen = true;
1303     CodeGenPasses.add(
1304         createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
1305     if (!CodeGenOpts.SplitDwarfOutput.empty()) {
1306       DwoOS = openOutputFile(CodeGenOpts.SplitDwarfOutput);
1307       if (!DwoOS)
1308         return;
1309     }
1310     if (!AddEmitPasses(CodeGenPasses, Action, *OS,
1311                        DwoOS ? &DwoOS->os() : nullptr))
1312       // FIXME: Should we handle this error differently?
1313       return;
1314     break;
1315   }
1316
1317   // Before executing passes, print the final values of the LLVM options.
1318   cl::PrintOptionValues();
1319
1320   // Now that we have all of the passes ready, run them.
1321   {
1322     PrettyStackTraceString CrashInfo("Optimizer");
1323     MPM.run(*TheModule, MAM);
1324   }
1325
1326   // Now if needed, run the legacy PM for codegen.
1327   if (NeedCodeGen) {
1328     PrettyStackTraceString CrashInfo("Code generation");
1329     CodeGenPasses.run(*TheModule);
1330   }
1331
1332   if (ThinLinkOS)
1333     ThinLinkOS->keep();
1334   if (DwoOS)
1335     DwoOS->keep();
1336 }
1337
1338 Expected<BitcodeModule> clang::FindThinLTOModule(MemoryBufferRef MBRef) {
1339   Expected<std::vector<BitcodeModule>> BMsOrErr = getBitcodeModuleList(MBRef);
1340   if (!BMsOrErr)
1341     return BMsOrErr.takeError();
1342
1343   // The bitcode file may contain multiple modules, we want the one that is
1344   // marked as being the ThinLTO module.
1345   if (const BitcodeModule *Bm = FindThinLTOModule(*BMsOrErr))
1346     return *Bm;
1347
1348   return make_error<StringError>("Could not find module summary",
1349                                  inconvertibleErrorCode());
1350 }
1351
1352 BitcodeModule *clang::FindThinLTOModule(MutableArrayRef<BitcodeModule> BMs) {
1353   for (BitcodeModule &BM : BMs) {
1354     Expected<BitcodeLTOInfo> LTOInfo = BM.getLTOInfo();
1355     if (LTOInfo && LTOInfo->IsThinLTO)
1356       return &BM;
1357   }
1358   return nullptr;
1359 }
1360
1361 static void runThinLTOBackend(ModuleSummaryIndex *CombinedIndex, Module *M,
1362                               const HeaderSearchOptions &HeaderOpts,
1363                               const CodeGenOptions &CGOpts,
1364                               const clang::TargetOptions &TOpts,
1365                               const LangOptions &LOpts,
1366                               std::unique_ptr<raw_pwrite_stream> OS,
1367                               std::string SampleProfile,
1368                               std::string ProfileRemapping,
1369                               BackendAction Action) {
1370   StringMap<DenseMap<GlobalValue::GUID, GlobalValueSummary *>>
1371       ModuleToDefinedGVSummaries;
1372   CombinedIndex->collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
1373
1374   setCommandLineOpts(CGOpts);
1375
1376   // We can simply import the values mentioned in the combined index, since
1377   // we should only invoke this using the individual indexes written out
1378   // via a WriteIndexesThinBackend.
1379   FunctionImporter::ImportMapTy ImportList;
1380   for (auto &GlobalList : *CombinedIndex) {
1381     // Ignore entries for undefined references.
1382     if (GlobalList.second.SummaryList.empty())
1383       continue;
1384
1385     auto GUID = GlobalList.first;
1386     for (auto &Summary : GlobalList.second.SummaryList) {
1387       // Skip the summaries for the importing module. These are included to
1388       // e.g. record required linkage changes.
1389       if (Summary->modulePath() == M->getModuleIdentifier())
1390         continue;
1391       // Add an entry to provoke importing by thinBackend.
1392       ImportList[Summary->modulePath()].insert(GUID);
1393     }
1394   }
1395
1396   std::vector<std::unique_ptr<llvm::MemoryBuffer>> OwnedImports;
1397   MapVector<llvm::StringRef, llvm::BitcodeModule> ModuleMap;
1398
1399   for (auto &I : ImportList) {
1400     ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> MBOrErr =
1401         llvm::MemoryBuffer::getFile(I.first());
1402     if (!MBOrErr) {
1403       errs() << "Error loading imported file '" << I.first()
1404              << "': " << MBOrErr.getError().message() << "\n";
1405       return;
1406     }
1407
1408     Expected<BitcodeModule> BMOrErr = FindThinLTOModule(**MBOrErr);
1409     if (!BMOrErr) {
1410       handleAllErrors(BMOrErr.takeError(), [&](ErrorInfoBase &EIB) {
1411         errs() << "Error loading imported file '" << I.first()
1412                << "': " << EIB.message() << '\n';
1413       });
1414       return;
1415     }
1416     ModuleMap.insert({I.first(), *BMOrErr});
1417
1418     OwnedImports.push_back(std::move(*MBOrErr));
1419   }
1420   auto AddStream = [&](size_t Task) {
1421     return std::make_unique<lto::NativeObjectStream>(std::move(OS));
1422   };
1423   lto::Config Conf;
1424   if (CGOpts.SaveTempsFilePrefix != "") {
1425     if (Error E = Conf.addSaveTemps(CGOpts.SaveTempsFilePrefix + ".",
1426                                     /* UseInputModulePath */ false)) {
1427       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1428         errs() << "Error setting up ThinLTO save-temps: " << EIB.message()
1429                << '\n';
1430       });
1431     }
1432   }
1433   Conf.CPU = TOpts.CPU;
1434   Conf.CodeModel = getCodeModel(CGOpts);
1435   Conf.MAttrs = TOpts.Features;
1436   Conf.RelocModel = CGOpts.RelocationModel;
1437   Conf.CGOptLevel = getCGOptLevel(CGOpts);
1438   Conf.OptLevel = CGOpts.OptimizationLevel;
1439   initTargetOptions(Conf.Options, CGOpts, TOpts, LOpts, HeaderOpts);
1440   Conf.SampleProfile = std::move(SampleProfile);
1441   Conf.PTO.LoopUnrolling = CGOpts.UnrollLoops;
1442   // For historical reasons, loop interleaving is set to mirror setting for loop
1443   // unrolling.
1444   Conf.PTO.LoopInterleaving = CGOpts.UnrollLoops;
1445   Conf.PTO.LoopVectorization = CGOpts.VectorizeLoop;
1446   Conf.PTO.SLPVectorization = CGOpts.VectorizeSLP;
1447
1448   // Context sensitive profile.
1449   if (CGOpts.hasProfileCSIRInstr()) {
1450     Conf.RunCSIRInstr = true;
1451     Conf.CSIRProfile = std::move(CGOpts.InstrProfileOutput);
1452   } else if (CGOpts.hasProfileCSIRUse()) {
1453     Conf.RunCSIRInstr = false;
1454     Conf.CSIRProfile = std::move(CGOpts.ProfileInstrumentUsePath);
1455   }
1456
1457   Conf.ProfileRemapping = std::move(ProfileRemapping);
1458   Conf.UseNewPM = CGOpts.ExperimentalNewPassManager;
1459   Conf.DebugPassManager = CGOpts.DebugPassManager;
1460   Conf.RemarksWithHotness = CGOpts.DiagnosticsWithHotness;
1461   Conf.RemarksFilename = CGOpts.OptRecordFile;
1462   Conf.RemarksPasses = CGOpts.OptRecordPasses;
1463   Conf.RemarksFormat = CGOpts.OptRecordFormat;
1464   Conf.SplitDwarfFile = CGOpts.SplitDwarfFile;
1465   Conf.SplitDwarfOutput = CGOpts.SplitDwarfOutput;
1466   switch (Action) {
1467   case Backend_EmitNothing:
1468     Conf.PreCodeGenModuleHook = [](size_t Task, const Module &Mod) {
1469       return false;
1470     };
1471     break;
1472   case Backend_EmitLL:
1473     Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1474       M->print(*OS, nullptr, CGOpts.EmitLLVMUseLists);
1475       return false;
1476     };
1477     break;
1478   case Backend_EmitBC:
1479     Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1480       WriteBitcodeToFile(*M, *OS, CGOpts.EmitLLVMUseLists);
1481       return false;
1482     };
1483     break;
1484   default:
1485     Conf.CGFileType = getCodeGenFileType(Action);
1486     break;
1487   }
1488   if (Error E = thinBackend(
1489           Conf, -1, AddStream, *M, *CombinedIndex, ImportList,
1490           ModuleToDefinedGVSummaries[M->getModuleIdentifier()], ModuleMap)) {
1491     handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1492       errs() << "Error running ThinLTO backend: " << EIB.message() << '\n';
1493     });
1494   }
1495 }
1496
1497 void clang::EmitBackendOutput(DiagnosticsEngine &Diags,
1498                               const HeaderSearchOptions &HeaderOpts,
1499                               const CodeGenOptions &CGOpts,
1500                               const clang::TargetOptions &TOpts,
1501                               const LangOptions &LOpts,
1502                               const llvm::DataLayout &TDesc, Module *M,
1503                               BackendAction Action,
1504                               std::unique_ptr<raw_pwrite_stream> OS) {
1505
1506   llvm::TimeTraceScope TimeScope("Backend");
1507
1508   std::unique_ptr<llvm::Module> EmptyModule;
1509   if (!CGOpts.ThinLTOIndexFile.empty()) {
1510     // If we are performing a ThinLTO importing compile, load the function index
1511     // into memory and pass it into runThinLTOBackend, which will run the
1512     // function importer and invoke LTO passes.
1513     Expected<std::unique_ptr<ModuleSummaryIndex>> IndexOrErr =
1514         llvm::getModuleSummaryIndexForFile(CGOpts.ThinLTOIndexFile,
1515                                            /*IgnoreEmptyThinLTOIndexFile*/true);
1516     if (!IndexOrErr) {
1517       logAllUnhandledErrors(IndexOrErr.takeError(), errs(),
1518                             "Error loading index file '" +
1519                             CGOpts.ThinLTOIndexFile + "': ");
1520       return;
1521     }
1522     std::unique_ptr<ModuleSummaryIndex> CombinedIndex = std::move(*IndexOrErr);
1523     // A null CombinedIndex means we should skip ThinLTO compilation
1524     // (LLVM will optionally ignore empty index files, returning null instead
1525     // of an error).
1526     if (CombinedIndex) {
1527       if (!CombinedIndex->skipModuleByDistributedBackend()) {
1528         runThinLTOBackend(CombinedIndex.get(), M, HeaderOpts, CGOpts, TOpts,
1529                           LOpts, std::move(OS), CGOpts.SampleProfileFile,
1530                           CGOpts.ProfileRemappingFile, Action);
1531         return;
1532       }
1533       // Distributed indexing detected that nothing from the module is needed
1534       // for the final linking. So we can skip the compilation. We sill need to
1535       // output an empty object file to make sure that a linker does not fail
1536       // trying to read it. Also for some features, like CFI, we must skip
1537       // the compilation as CombinedIndex does not contain all required
1538       // information.
1539       EmptyModule = std::make_unique<llvm::Module>("empty", M->getContext());
1540       EmptyModule->setTargetTriple(M->getTargetTriple());
1541       M = EmptyModule.get();
1542     }
1543   }
1544
1545   EmitAssemblyHelper AsmHelper(Diags, HeaderOpts, CGOpts, TOpts, LOpts, M);
1546
1547   if (CGOpts.ExperimentalNewPassManager)
1548     AsmHelper.EmitAssemblyWithNewPassManager(Action, std::move(OS));
1549   else
1550     AsmHelper.EmitAssembly(Action, std::move(OS));
1551
1552   // Verify clang's TargetInfo DataLayout against the LLVM TargetMachine's
1553   // DataLayout.
1554   if (AsmHelper.TM) {
1555     std::string DLDesc = M->getDataLayout().getStringRepresentation();
1556     if (DLDesc != TDesc.getStringRepresentation()) {
1557       unsigned DiagID = Diags.getCustomDiagID(
1558           DiagnosticsEngine::Error, "backend data layout '%0' does not match "
1559                                     "expected target description '%1'");
1560       Diags.Report(DiagID) << DLDesc << TDesc.getStringRepresentation();
1561     }
1562   }
1563 }
1564
1565 // With -fembed-bitcode, save a copy of the llvm IR as data in the
1566 // __LLVM,__bitcode section.
1567 void clang::EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts,
1568                          llvm::MemoryBufferRef Buf) {
1569   if (CGOpts.getEmbedBitcode() == CodeGenOptions::Embed_Off)
1570     return;
1571   llvm::EmbedBitcodeInModule(
1572       *M, Buf, CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Marker,
1573       CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Bitcode,
1574       &CGOpts.CmdArgs);
1575 }