contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp

   1 //===--- BackendUtil.cpp - LLVM Backend Utilities -------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "clang/CodeGen/BackendUtil.h"
  11 #include "clang/Basic/CodeGenOptions.h"
  12 #include "clang/Basic/Diagnostic.h"
  13 #include "clang/Basic/LangOptions.h"
  14 #include "clang/Basic/TargetOptions.h"
  15 #include "clang/Frontend/FrontendDiagnostic.h"
  16 #include "clang/Frontend/Utils.h"
  17 #include "clang/Lex/HeaderSearchOptions.h"
  18 #include "llvm/ADT/SmallSet.h"
  19 #include "llvm/ADT/StringExtras.h"
  20 #include "llvm/ADT/StringSwitch.h"
  21 #include "llvm/ADT/Triple.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/IRPrintingPasses.h"
  32 #include "llvm/IR/LegacyPassManager.h"
  33 #include "llvm/IR/Module.h"
  34 #include "llvm/IR/ModuleSummaryIndex.h"
  35 #include "llvm/IR/Verifier.h"
  36 #include "llvm/LTO/LTOBackend.h"
  37 #include "llvm/MC/MCAsmInfo.h"
  38 #include "llvm/MC/SubtargetFeature.h"
  39 #include "llvm/Passes/PassBuilder.h"
  40 #include "llvm/Support/BuryPointer.h"
  41 #include "llvm/Support/CommandLine.h"
  42 #include "llvm/Support/MemoryBuffer.h"
  43 #include "llvm/Support/PrettyStackTrace.h"
  44 #include "llvm/Support/TargetRegistry.h"
  45 #include "llvm/Support/Timer.h"
  46 #include "llvm/Support/raw_ostream.h"
  47 #include "llvm/Target/TargetMachine.h"
  48 #include "llvm/Target/TargetOptions.h"
  49 #include "llvm/Transforms/Coroutines.h"
  50 #include "llvm/Transforms/IPO.h"
  51 #include "llvm/Transforms/IPO/AlwaysInliner.h"
  52 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
  53 #include "llvm/Transforms/IPO/ThinLTOBitcodeWriter.h"
  54 #include "llvm/Transforms/InstCombine/InstCombine.h"
  55 #include "llvm/Transforms/Instrumentation.h"
  56 #include "llvm/Transforms/Instrumentation/BoundsChecking.h"
  57 #include "llvm/Transforms/Instrumentation/GCOVProfiler.h"
  58 #include "llvm/Transforms/Instrumentation/MemorySanitizer.h"
  59 #include "llvm/Transforms/Instrumentation/ThreadSanitizer.h"
  60 #include "llvm/Transforms/ObjCARC.h"
  61 #include "llvm/Transforms/Scalar.h"
  62 #include "llvm/Transforms/Scalar/GVN.h"
  63 #include "llvm/Transforms/Utils.h"
  64 #include "llvm/Transforms/Utils/CanonicalizeAliases.h"
  65 #include "llvm/Transforms/Utils/NameAnonGlobals.h"
  66 #include "llvm/Transforms/Utils/SymbolRewriter.h"
  67 #include <memory>
  68 using namespace clang;
  69 using namespace llvm;
  70
  71 namespace {
  72
  73 // Default filename used for profile generation.
  74 static constexpr StringLiteral DefaultProfileGenName = "default_%m.profraw";
  75
  76 class EmitAssemblyHelper {
  77   DiagnosticsEngine &Diags;
  78   const HeaderSearchOptions &HSOpts;
  79   const CodeGenOptions &CodeGenOpts;
  80   const clang::TargetOptions &TargetOpts;
  81   const LangOptions &LangOpts;
  82   Module *TheModule;
  83
  84   Timer CodeGenerationTime;
  85
  86   std::unique_ptr<raw_pwrite_stream> OS;
  87
  88   TargetIRAnalysis getTargetIRAnalysis() const {
  89     if (TM)
  90       return TM->getTargetIRAnalysis();
  91
  92     return TargetIRAnalysis();
  93   }
  94
  95   void CreatePasses(legacy::PassManager &MPM, legacy::FunctionPassManager &FPM);
  96
  97   /// Generates the TargetMachine.
  98   /// Leaves TM unchanged if it is unable to create the target machine.
  99   /// Some of our clang tests specify triples which are not built
 100   /// into clang. This is okay because these tests check the generated
 101   /// IR, and they require DataLayout which depends on the triple.
 102   /// In this case, we allow this method to fail and not report an error.
 103   /// When MustCreateTM is used, we print an error if we are unable to load
 104   /// the requested target.
 105   void CreateTargetMachine(bool MustCreateTM);
 106
 107   /// Add passes necessary to emit assembly or LLVM IR.
 108   ///
 109   /// \return True on success.
 110   bool AddEmitPasses(legacy::PassManager &CodeGenPasses, BackendAction Action,
 111                      raw_pwrite_stream &OS, raw_pwrite_stream *DwoOS);
 112
 113   std::unique_ptr<llvm::ToolOutputFile> openOutputFile(StringRef Path) {
 114     std::error_code EC;
 115     auto F = llvm::make_unique<llvm::ToolOutputFile>(Path, EC,
 116                                                      llvm::sys::fs::F_None);
 117     if (EC) {
 118       Diags.Report(diag::err_fe_unable_to_open_output) << Path << EC.message();
 119       F.reset();
 120     }
 121     return F;
 122   }
 123
 124 public:
 125   EmitAssemblyHelper(DiagnosticsEngine &_Diags,
 126                      const HeaderSearchOptions &HeaderSearchOpts,
 127                      const CodeGenOptions &CGOpts,
 128                      const clang::TargetOptions &TOpts,
 129                      const LangOptions &LOpts, Module *M)
 130       : Diags(_Diags), HSOpts(HeaderSearchOpts), CodeGenOpts(CGOpts),
 131         TargetOpts(TOpts), LangOpts(LOpts), TheModule(M),
 132         CodeGenerationTime("codegen", "Code Generation Time") {}
 133
 134   ~EmitAssemblyHelper() {
 135     if (CodeGenOpts.DisableFree)
 136       BuryPointer(std::move(TM));
 137   }
 138
 139   std::unique_ptr<TargetMachine> TM;
 140
 141   void EmitAssembly(BackendAction Action,
 142                     std::unique_ptr<raw_pwrite_stream> OS);
 143
 144   void EmitAssemblyWithNewPassManager(BackendAction Action,
 145                                       std::unique_ptr<raw_pwrite_stream> OS);
 146 };
 147
 148 // We need this wrapper to access LangOpts and CGOpts from extension functions
 149 // that we add to the PassManagerBuilder.
 150 class PassManagerBuilderWrapper : public PassManagerBuilder {
 151 public:
 152   PassManagerBuilderWrapper(const Triple &TargetTriple,
 153                             const CodeGenOptions &CGOpts,
 154                             const LangOptions &LangOpts)
 155       : PassManagerBuilder(), TargetTriple(TargetTriple), CGOpts(CGOpts),
 156         LangOpts(LangOpts) {}
 157   const Triple &getTargetTriple() const { return TargetTriple; }
 158   const CodeGenOptions &getCGOpts() const { return CGOpts; }
 159   const LangOptions &getLangOpts() const { return LangOpts; }
 160
 161 private:
 162   const Triple &TargetTriple;
 163   const CodeGenOptions &CGOpts;
 164   const LangOptions &LangOpts;
 165 };
 166 }
 167
 168 static void addObjCARCAPElimPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
 169   if (Builder.OptLevel > 0)
 170     PM.add(createObjCARCAPElimPass());
 171 }
 172
 173 static void addObjCARCExpandPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
 174   if (Builder.OptLevel > 0)
 175     PM.add(createObjCARCExpandPass());
 176 }
 177
 178 static void addObjCARCOptPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
 179   if (Builder.OptLevel > 0)
 180     PM.add(createObjCARCOptPass());
 181 }
 182
 183 static void addAddDiscriminatorsPass(const PassManagerBuilder &Builder,
 184                                      legacy::PassManagerBase &PM) {
 185   PM.add(createAddDiscriminatorsPass());
 186 }
 187
 188 static void addBoundsCheckingPass(const PassManagerBuilder &Builder,
 189                                   legacy::PassManagerBase &PM) {
 190   PM.add(createBoundsCheckingLegacyPass());
 191 }
 192
 193 static void addSanitizerCoveragePass(const PassManagerBuilder &Builder,
 194                                      legacy::PassManagerBase &PM) {
 195   const PassManagerBuilderWrapper &BuilderWrapper =
 196       static_cast<const PassManagerBuilderWrapper&>(Builder);
 197   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
 198   SanitizerCoverageOptions Opts;
 199   Opts.CoverageType =
 200       static_cast<SanitizerCoverageOptions::Type>(CGOpts.SanitizeCoverageType);
 201   Opts.IndirectCalls = CGOpts.SanitizeCoverageIndirectCalls;
 202   Opts.TraceBB = CGOpts.SanitizeCoverageTraceBB;
 203   Opts.TraceCmp = CGOpts.SanitizeCoverageTraceCmp;
 204   Opts.TraceDiv = CGOpts.SanitizeCoverageTraceDiv;
 205   Opts.TraceGep = CGOpts.SanitizeCoverageTraceGep;
 206   Opts.Use8bitCounters = CGOpts.SanitizeCoverage8bitCounters;
 207   Opts.TracePC = CGOpts.SanitizeCoverageTracePC;
 208   Opts.TracePCGuard = CGOpts.SanitizeCoverageTracePCGuard;
 209   Opts.NoPrune = CGOpts.SanitizeCoverageNoPrune;
 210   Opts.Inline8bitCounters = CGOpts.SanitizeCoverageInline8bitCounters;
 211   Opts.PCTable = CGOpts.SanitizeCoveragePCTable;
 212   Opts.StackDepth = CGOpts.SanitizeCoverageStackDepth;
 213   PM.add(createSanitizerCoverageModulePass(Opts));
 214 }
 215
 216 // Check if ASan should use GC-friendly instrumentation for globals.
 217 // First of all, there is no point if -fdata-sections is off (expect for MachO,
 218 // where this is not a factor). Also, on ELF this feature requires an assembler
 219 // extension that only works with -integrated-as at the moment.
 220 static bool asanUseGlobalsGC(const Triple &T, const CodeGenOptions &CGOpts) {
 221   if (!CGOpts.SanitizeAddressGlobalsDeadStripping)
 222     return false;
 223   switch (T.getObjectFormat()) {
 224   case Triple::MachO:
 225   case Triple::COFF:
 226     return true;
 227   case Triple::ELF:
 228     return CGOpts.DataSections && !CGOpts.DisableIntegratedAS;
 229   default:
 230     return false;
 231   }
 232 }
 233
 234 static void addAddressSanitizerPasses(const PassManagerBuilder &Builder,
 235                                       legacy::PassManagerBase &PM) {
 236   const PassManagerBuilderWrapper &BuilderWrapper =
 237       static_cast<const PassManagerBuilderWrapper&>(Builder);
 238   const Triple &T = BuilderWrapper.getTargetTriple();
 239   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
 240   bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Address);
 241   bool UseAfterScope = CGOpts.SanitizeAddressUseAfterScope;
 242   bool UseOdrIndicator = CGOpts.SanitizeAddressUseOdrIndicator;
 243   bool UseGlobalsGC = asanUseGlobalsGC(T, CGOpts);
 244   PM.add(createAddressSanitizerFunctionPass(/*CompileKernel*/ false, Recover,
 245                                             UseAfterScope));
 246   PM.add(createAddressSanitizerModulePass(/*CompileKernel*/ false, Recover,
 247                                           UseGlobalsGC, UseOdrIndicator));
 248 }
 249
 250 static void addKernelAddressSanitizerPasses(const PassManagerBuilder &Builder,
 251                                             legacy::PassManagerBase &PM) {
 252   PM.add(createAddressSanitizerFunctionPass(
 253       /*CompileKernel*/ true, /*Recover*/ true, /*UseAfterScope*/ false));
 254   PM.add(createAddressSanitizerModulePass(
 255       /*CompileKernel*/ true, /*Recover*/ true, /*UseGlobalsGC*/ true,
 256       /*UseOdrIndicator*/ false));
 257 }
 258
 259 static void addHWAddressSanitizerPasses(const PassManagerBuilder &Builder,
 260                                             legacy::PassManagerBase &PM) {
 261   const PassManagerBuilderWrapper &BuilderWrapper =
 262       static_cast<const PassManagerBuilderWrapper &>(Builder);
 263   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
 264   bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::HWAddress);
 265   PM.add(createHWAddressSanitizerPass(/*CompileKernel*/ false, Recover));
 266 }
 267
 268 static void addKernelHWAddressSanitizerPasses(const PassManagerBuilder &Builder,
 269                                             legacy::PassManagerBase &PM) {
 270   PM.add(createHWAddressSanitizerPass(
 271       /*CompileKernel*/ true, /*Recover*/ true));
 272 }
 273
 274 static void addGeneralOptsForMemorySanitizer(const PassManagerBuilder &Builder,
 275                                              legacy::PassManagerBase &PM,
 276                                              bool CompileKernel) {
 277   const PassManagerBuilderWrapper &BuilderWrapper =
 278       static_cast<const PassManagerBuilderWrapper&>(Builder);
 279   const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
 280   int TrackOrigins = CGOpts.SanitizeMemoryTrackOrigins;
 281   bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Memory);
 282   PM.add(createMemorySanitizerLegacyPassPass(TrackOrigins, Recover, CompileKernel));
 283
 284   // MemorySanitizer inserts complex instrumentation that mostly follows
 285   // the logic of the original code, but operates on "shadow" values.
 286   // It can benefit from re-running some general purpose optimization passes.
 287   if (Builder.OptLevel > 0) {
 288     PM.add(createEarlyCSEPass());
 289     PM.add(createReassociatePass());
 290     PM.add(createLICMPass());
 291     PM.add(createGVNPass());
 292     PM.add(createInstructionCombiningPass());
 293     PM.add(createDeadStoreEliminationPass());
 294   }
 295 }
 296
 297 static void addMemorySanitizerPass(const PassManagerBuilder &Builder,
 298                                    legacy::PassManagerBase &PM) {
 299   addGeneralOptsForMemorySanitizer(Builder, PM, /*CompileKernel*/ false);
 300 }
 301
 302 static void addKernelMemorySanitizerPass(const PassManagerBuilder &Builder,
 303                                          legacy::PassManagerBase &PM) {
 304   addGeneralOptsForMemorySanitizer(Builder, PM, /*CompileKernel*/ true);
 305 }
 306
 307 static void addThreadSanitizerPass(const PassManagerBuilder &Builder,
 308                                    legacy::PassManagerBase &PM) {
 309   PM.add(createThreadSanitizerLegacyPassPass());
 310 }
 311
 312 static void addDataFlowSanitizerPass(const PassManagerBuilder &Builder,
 313                                      legacy::PassManagerBase &PM) {
 314   const PassManagerBuilderWrapper &BuilderWrapper =
 315       static_cast<const PassManagerBuilderWrapper&>(Builder);
 316   const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
 317   PM.add(createDataFlowSanitizerPass(LangOpts.SanitizerBlacklistFiles));
 318 }
 319
 320 static void addEfficiencySanitizerPass(const PassManagerBuilder &Builder,
 321                                        legacy::PassManagerBase &PM) {
 322   const PassManagerBuilderWrapper &BuilderWrapper =
 323       static_cast<const PassManagerBuilderWrapper&>(Builder);
 324   const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
 325   EfficiencySanitizerOptions Opts;
 326   if (LangOpts.Sanitize.has(SanitizerKind::EfficiencyCacheFrag))
 327     Opts.ToolType = EfficiencySanitizerOptions::ESAN_CacheFrag;
 328   else if (LangOpts.Sanitize.has(SanitizerKind::EfficiencyWorkingSet))
 329     Opts.ToolType = EfficiencySanitizerOptions::ESAN_WorkingSet;
 330   PM.add(createEfficiencySanitizerPass(Opts));
 331 }
 332
 333 static TargetLibraryInfoImpl *createTLII(llvm::Triple &TargetTriple,
 334                                          const CodeGenOptions &CodeGenOpts) {
 335   TargetLibraryInfoImpl *TLII = new TargetLibraryInfoImpl(TargetTriple);
 336   if (!CodeGenOpts.SimplifyLibCalls)
 337     TLII->disableAllFunctions();
 338   else {
 339     // Disable individual libc/libm calls in TargetLibraryInfo.
 340     LibFunc F;
 341     for (auto &FuncName : CodeGenOpts.getNoBuiltinFuncs())
 342       if (TLII->getLibFunc(FuncName, F))
 343         TLII->setUnavailable(F);
 344   }
 345
 346   switch (CodeGenOpts.getVecLib()) {
 347   case CodeGenOptions::Accelerate:
 348     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::Accelerate);
 349     break;
 350   case CodeGenOptions::SVML:
 351     TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::SVML);
 352     break;
 353   default:
 354     break;
 355   }
 356   return TLII;
 357 }
 358
 359 static void addSymbolRewriterPass(const CodeGenOptions &Opts,
 360                                   legacy::PassManager *MPM) {
 361   llvm::SymbolRewriter::RewriteDescriptorList DL;
 362
 363   llvm::SymbolRewriter::RewriteMapParser MapParser;
 364   for (const auto &MapFile : Opts.RewriteMapFiles)
 365     MapParser.parse(MapFile, &DL);
 366
 367   MPM->add(createRewriteSymbolsPass(DL));
 368 }
 369
 370 static CodeGenOpt::Level getCGOptLevel(const CodeGenOptions &CodeGenOpts) {
 371   switch (CodeGenOpts.OptimizationLevel) {
 372   default:
 373     llvm_unreachable("Invalid optimization level!");
 374   case 0:
 375     return CodeGenOpt::None;
 376   case 1:
 377     return CodeGenOpt::Less;
 378   case 2:
 379     return CodeGenOpt::Default; // O2/Os/Oz
 380   case 3:
 381     return CodeGenOpt::Aggressive;
 382   }
 383 }
 384
 385 static Optional<llvm::CodeModel::Model>
 386 getCodeModel(const CodeGenOptions &CodeGenOpts) {
 387   unsigned CodeModel = llvm::StringSwitch<unsigned>(CodeGenOpts.CodeModel)
 388                            .Case("tiny", llvm::CodeModel::Tiny)
 389                            .Case("small", llvm::CodeModel::Small)
 390                            .Case("kernel", llvm::CodeModel::Kernel)
 391                            .Case("medium", llvm::CodeModel::Medium)
 392                            .Case("large", llvm::CodeModel::Large)
 393                            .Case("default", ~1u)
 394                            .Default(~0u);
 395   assert(CodeModel != ~0u && "invalid code model!");
 396   if (CodeModel == ~1u)
 397     return None;
 398   return static_cast<llvm::CodeModel::Model>(CodeModel);
 399 }
 400
 401 static TargetMachine::CodeGenFileType getCodeGenFileType(BackendAction Action) {
 402   if (Action == Backend_EmitObj)
 403     return TargetMachine::CGFT_ObjectFile;
 404   else if (Action == Backend_EmitMCNull)
 405     return TargetMachine::CGFT_Null;
 406   else {
 407     assert(Action == Backend_EmitAssembly && "Invalid action!");
 408     return TargetMachine::CGFT_AssemblyFile;
 409   }
 410 }
 411
 412 static void initTargetOptions(llvm::TargetOptions &Options,
 413                               const CodeGenOptions &CodeGenOpts,
 414                               const clang::TargetOptions &TargetOpts,
 415                               const LangOptions &LangOpts,
 416                               const HeaderSearchOptions &HSOpts) {
 417   Options.ThreadModel =
 418       llvm::StringSwitch<llvm::ThreadModel::Model>(CodeGenOpts.ThreadModel)
 419           .Case("posix", llvm::ThreadModel::POSIX)
 420           .Case("single", llvm::ThreadModel::Single);
 421
 422   // Set float ABI type.
 423   assert((CodeGenOpts.FloatABI == "soft" || CodeGenOpts.FloatABI == "softfp" ||
 424           CodeGenOpts.FloatABI == "hard" || CodeGenOpts.FloatABI.empty()) &&
 425          "Invalid Floating Point ABI!");
 426   Options.FloatABIType =
 427       llvm::StringSwitch<llvm::FloatABI::ABIType>(CodeGenOpts.FloatABI)
 428           .Case("soft", llvm::FloatABI::Soft)
 429           .Case("softfp", llvm::FloatABI::Soft)
 430           .Case("hard", llvm::FloatABI::Hard)
 431           .Default(llvm::FloatABI::Default);
 432
 433   // Set FP fusion mode.
 434   switch (LangOpts.getDefaultFPContractMode()) {
 435   case LangOptions::FPC_Off:
 436     // Preserve any contraction performed by the front-end.  (Strict performs
 437     // splitting of the muladd intrinsic in the backend.)
 438     Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
 439     break;
 440   case LangOptions::FPC_On:
 441     Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
 442     break;
 443   case LangOptions::FPC_Fast:
 444     Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
 445     break;
 446   }
 447
 448   Options.UseInitArray = CodeGenOpts.UseInitArray;
 449   Options.DisableIntegratedAS = CodeGenOpts.DisableIntegratedAS;
 450   Options.CompressDebugSections = CodeGenOpts.getCompressDebugSections();
 451   Options.RelaxELFRelocations = CodeGenOpts.RelaxELFRelocations;
 452
 453   // Set EABI version.
 454   Options.EABIVersion = TargetOpts.EABIVersion;
 455
 456   if (LangOpts.SjLjExceptions)
 457     Options.ExceptionModel = llvm::ExceptionHandling::SjLj;
 458   if (LangOpts.SEHExceptions)
 459     Options.ExceptionModel = llvm::ExceptionHandling::WinEH;
 460   if (LangOpts.DWARFExceptions)
 461     Options.ExceptionModel = llvm::ExceptionHandling::DwarfCFI;
 462
 463   Options.NoInfsFPMath = CodeGenOpts.NoInfsFPMath;
 464   Options.NoNaNsFPMath = CodeGenOpts.NoNaNsFPMath;
 465   Options.NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS;
 466   Options.UnsafeFPMath = CodeGenOpts.UnsafeFPMath;
 467   Options.StackAlignmentOverride = CodeGenOpts.StackAlignment;
 468   Options.FunctionSections = CodeGenOpts.FunctionSections;
 469   Options.DataSections = CodeGenOpts.DataSections;
 470   Options.UniqueSectionNames = CodeGenOpts.UniqueSectionNames;
 471   Options.EmulatedTLS = CodeGenOpts.EmulatedTLS;
 472   Options.ExplicitEmulatedTLS = CodeGenOpts.ExplicitEmulatedTLS;
 473   Options.DebuggerTuning = CodeGenOpts.getDebuggerTuning();
 474   Options.EmitStackSizeSection = CodeGenOpts.StackSizeSection;
 475   Options.EmitAddrsig = CodeGenOpts.Addrsig;
 476
 477   if (CodeGenOpts.getSplitDwarfMode() != CodeGenOptions::NoFission)
 478     Options.MCOptions.SplitDwarfFile = CodeGenOpts.SplitDwarfFile;
 479   Options.MCOptions.MCRelaxAll = CodeGenOpts.RelaxAll;
 480   Options.MCOptions.MCSaveTempLabels = CodeGenOpts.SaveTempLabels;
 481   Options.MCOptions.MCUseDwarfDirectory = !CodeGenOpts.NoDwarfDirectoryAsm;
 482   Options.MCOptions.MCNoExecStack = CodeGenOpts.NoExecStack;
 483   Options.MCOptions.MCIncrementalLinkerCompatible =
 484       CodeGenOpts.IncrementalLinkerCompatible;
 485   Options.MCOptions.MCPIECopyRelocations = CodeGenOpts.PIECopyRelocations;
 486   Options.MCOptions.MCFatalWarnings = CodeGenOpts.FatalWarnings;
 487   Options.MCOptions.AsmVerbose = CodeGenOpts.AsmVerbose;
 488   Options.MCOptions.PreserveAsmComments = CodeGenOpts.PreserveAsmComments;
 489   Options.MCOptions.ABIName = TargetOpts.ABI;
 490   for (const auto &Entry : HSOpts.UserEntries)
 491     if (!Entry.IsFramework &&
 492         (Entry.Group == frontend::IncludeDirGroup::Quoted ||
 493          Entry.Group == frontend::IncludeDirGroup::Angled ||
 494          Entry.Group == frontend::IncludeDirGroup::System))
 495       Options.MCOptions.IASSearchPaths.push_back(
 496           Entry.IgnoreSysRoot ? Entry.Path : HSOpts.Sysroot + Entry.Path);
 497 }
 498 static Optional<GCOVOptions> getGCOVOptions(const CodeGenOptions &CodeGenOpts) {
 499   if (CodeGenOpts.DisableGCov)
 500     return None;
 501   if (!CodeGenOpts.EmitGcovArcs && !CodeGenOpts.EmitGcovNotes)
 502     return None;
 503   // Not using 'GCOVOptions::getDefault' allows us to avoid exiting if
 504   // LLVM's -default-gcov-version flag is set to something invalid.
 505   GCOVOptions Options;
 506   Options.EmitNotes = CodeGenOpts.EmitGcovNotes;
 507   Options.EmitData = CodeGenOpts.EmitGcovArcs;
 508   llvm::copy(CodeGenOpts.CoverageVersion, std::begin(Options.Version));
 509   Options.UseCfgChecksum = CodeGenOpts.CoverageExtraChecksum;
 510   Options.NoRedZone = CodeGenOpts.DisableRedZone;
 511   Options.FunctionNamesInData = !CodeGenOpts.CoverageNoFunctionNamesInData;
 512   Options.Filter = CodeGenOpts.ProfileFilterFiles;
 513   Options.Exclude = CodeGenOpts.ProfileExcludeFiles;
 514   Options.ExitBlockBeforeBody = CodeGenOpts.CoverageExitBlockBeforeBody;
 515   return Options;
 516 }
 517
 518 void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
 519                                       legacy::FunctionPassManager &FPM) {
 520   // Handle disabling of all LLVM passes, where we want to preserve the
 521   // internal module before any optimization.
 522   if (CodeGenOpts.DisableLLVMPasses)
 523     return;
 524
 525   // Figure out TargetLibraryInfo.  This needs to be added to MPM and FPM
 526   // manually (and not via PMBuilder), since some passes (eg. InstrProfiling)
 527   // are inserted before PMBuilder ones - they'd get the default-constructed
 528   // TLI with an unknown target otherwise.
 529   Triple TargetTriple(TheModule->getTargetTriple());
 530   std::unique_ptr<TargetLibraryInfoImpl> TLII(
 531       createTLII(TargetTriple, CodeGenOpts));
 532
 533   PassManagerBuilderWrapper PMBuilder(TargetTriple, CodeGenOpts, LangOpts);
 534
 535   // At O0 and O1 we only run the always inliner which is more efficient. At
 536   // higher optimization levels we run the normal inliner.
 537   if (CodeGenOpts.OptimizationLevel <= 1) {
 538     bool InsertLifetimeIntrinsics = (CodeGenOpts.OptimizationLevel != 0 &&
 539                                      !CodeGenOpts.DisableLifetimeMarkers);
 540     PMBuilder.Inliner = createAlwaysInlinerLegacyPass(InsertLifetimeIntrinsics);
 541   } else {
 542     // We do not want to inline hot callsites for SamplePGO module-summary build
 543     // because profile annotation will happen again in ThinLTO backend, and we
 544     // want the IR of the hot path to match the profile.
 545     PMBuilder.Inliner = createFunctionInliningPass(
 546         CodeGenOpts.OptimizationLevel, CodeGenOpts.OptimizeSize,
 547         (!CodeGenOpts.SampleProfileFile.empty() &&
 548          CodeGenOpts.PrepareForThinLTO));
 549   }
 550
 551   PMBuilder.OptLevel = CodeGenOpts.OptimizationLevel;
 552   PMBuilder.SizeLevel = CodeGenOpts.OptimizeSize;
 553   PMBuilder.SLPVectorize = CodeGenOpts.VectorizeSLP;
 554   PMBuilder.LoopVectorize = CodeGenOpts.VectorizeLoop;
 555
 556   PMBuilder.DisableUnrollLoops = !CodeGenOpts.UnrollLoops;
 557   PMBuilder.MergeFunctions = CodeGenOpts.MergeFunctions;
 558   PMBuilder.PrepareForThinLTO = CodeGenOpts.PrepareForThinLTO;
 559   PMBuilder.PrepareForLTO = CodeGenOpts.PrepareForLTO;
 560   PMBuilder.RerollLoops = CodeGenOpts.RerollLoops;
 561
 562   MPM.add(new TargetLibraryInfoWrapperPass(*TLII));
 563
 564   if (TM)
 565     TM->adjustPassManager(PMBuilder);
 566
 567   if (CodeGenOpts.DebugInfoForProfiling ||
 568       !CodeGenOpts.SampleProfileFile.empty())
 569     PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
 570                            addAddDiscriminatorsPass);
 571
 572   // In ObjC ARC mode, add the main ARC optimization passes.
 573   if (LangOpts.ObjCAutoRefCount) {
 574     PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
 575                            addObjCARCExpandPass);
 576     PMBuilder.addExtension(PassManagerBuilder::EP_ModuleOptimizerEarly,
 577                            addObjCARCAPElimPass);
 578     PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
 579                            addObjCARCOptPass);
 580   }
 581
 582   if (LangOpts.CoroutinesTS)
 583     addCoroutinePassesToExtensionPoints(PMBuilder);
 584
 585   if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds)) {
 586     PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
 587                            addBoundsCheckingPass);
 588     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 589                            addBoundsCheckingPass);
 590   }
 591
 592   if (CodeGenOpts.SanitizeCoverageType ||
 593       CodeGenOpts.SanitizeCoverageIndirectCalls ||
 594       CodeGenOpts.SanitizeCoverageTraceCmp) {
 595     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 596                            addSanitizerCoveragePass);
 597     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 598                            addSanitizerCoveragePass);
 599   }
 600
 601   if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
 602     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 603                            addAddressSanitizerPasses);
 604     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 605                            addAddressSanitizerPasses);
 606   }
 607
 608   if (LangOpts.Sanitize.has(SanitizerKind::KernelAddress)) {
 609     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 610                            addKernelAddressSanitizerPasses);
 611     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 612                            addKernelAddressSanitizerPasses);
 613   }
 614
 615   if (LangOpts.Sanitize.has(SanitizerKind::HWAddress)) {
 616     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 617                            addHWAddressSanitizerPasses);
 618     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 619                            addHWAddressSanitizerPasses);
 620   }
 621
 622   if (LangOpts.Sanitize.has(SanitizerKind::KernelHWAddress)) {
 623     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 624                            addKernelHWAddressSanitizerPasses);
 625     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 626                            addKernelHWAddressSanitizerPasses);
 627   }
 628
 629   if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
 630     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 631                            addMemorySanitizerPass);
 632     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 633                            addMemorySanitizerPass);
 634   }
 635
 636   if (LangOpts.Sanitize.has(SanitizerKind::KernelMemory)) {
 637     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 638                            addKernelMemorySanitizerPass);
 639     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 640                            addKernelMemorySanitizerPass);
 641   }
 642
 643   if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
 644     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 645                            addThreadSanitizerPass);
 646     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 647                            addThreadSanitizerPass);
 648   }
 649
 650   if (LangOpts.Sanitize.has(SanitizerKind::DataFlow)) {
 651     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 652                            addDataFlowSanitizerPass);
 653     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 654                            addDataFlowSanitizerPass);
 655   }
 656
 657   if (LangOpts.Sanitize.hasOneOf(SanitizerKind::Efficiency)) {
 658     PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
 659                            addEfficiencySanitizerPass);
 660     PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
 661                            addEfficiencySanitizerPass);
 662   }
 663
 664   // Set up the per-function pass manager.
 665   FPM.add(new TargetLibraryInfoWrapperPass(*TLII));
 666   if (CodeGenOpts.VerifyModule)
 667     FPM.add(createVerifierPass());
 668
 669   // Set up the per-module pass manager.
 670   if (!CodeGenOpts.RewriteMapFiles.empty())
 671     addSymbolRewriterPass(CodeGenOpts, &MPM);
 672
 673   if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts)) {
 674     MPM.add(createGCOVProfilerPass(*Options));
 675     if (CodeGenOpts.getDebugInfo() == codegenoptions::NoDebugInfo)
 676       MPM.add(createStripSymbolsPass(true));
 677   }
 678
 679   if (CodeGenOpts.hasProfileClangInstr()) {
 680     InstrProfOptions Options;
 681     Options.NoRedZone = CodeGenOpts.DisableRedZone;
 682     Options.InstrProfileOutput = CodeGenOpts.InstrProfileOutput;
 683
 684     // TODO: Surface the option to emit atomic profile counter increments at
 685     // the driver level.
 686     Options.Atomic = LangOpts.Sanitize.has(SanitizerKind::Thread);
 687
 688     MPM.add(createInstrProfilingLegacyPass(Options));
 689   }
 690   if (CodeGenOpts.hasProfileIRInstr()) {
 691     PMBuilder.EnablePGOInstrGen = true;
 692     if (!CodeGenOpts.InstrProfileOutput.empty())
 693       PMBuilder.PGOInstrGen = CodeGenOpts.InstrProfileOutput;
 694     else
 695       PMBuilder.PGOInstrGen = DefaultProfileGenName;
 696   }
 697   if (CodeGenOpts.hasProfileIRUse())
 698     PMBuilder.PGOInstrUse = CodeGenOpts.ProfileInstrumentUsePath;
 699
 700   if (!CodeGenOpts.SampleProfileFile.empty())
 701     PMBuilder.PGOSampleUse = CodeGenOpts.SampleProfileFile;
 702
 703   PMBuilder.populateFunctionPassManager(FPM);
 704   PMBuilder.populateModulePassManager(MPM);
 705 }
 706
 707 static void setCommandLineOpts(const CodeGenOptions &CodeGenOpts) {
 708   SmallVector<const char *, 16> BackendArgs;
 709   BackendArgs.push_back("clang"); // Fake program name.
 710   if (!CodeGenOpts.DebugPass.empty()) {
 711     BackendArgs.push_back("-debug-pass");
 712     BackendArgs.push_back(CodeGenOpts.DebugPass.c_str());
 713   }
 714   if (!CodeGenOpts.LimitFloatPrecision.empty()) {
 715     BackendArgs.push_back("-limit-float-precision");
 716     BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
 717   }
 718   BackendArgs.push_back(nullptr);
 719   llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
 720                                     BackendArgs.data());
 721 }
 722
 723 void EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
 724   // Create the TargetMachine for generating code.
 725   std::string Error;
 726   std::string Triple = TheModule->getTargetTriple();
 727   const llvm::Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error);
 728   if (!TheTarget) {
 729     if (MustCreateTM)
 730       Diags.Report(diag::err_fe_unable_to_create_target) << Error;
 731     return;
 732   }
 733
 734   Optional<llvm::CodeModel::Model> CM = getCodeModel(CodeGenOpts);
 735   std::string FeaturesStr =
 736       llvm::join(TargetOpts.Features.begin(), TargetOpts.Features.end(), ",");
 737   llvm::Reloc::Model RM = CodeGenOpts.RelocationModel;
 738   CodeGenOpt::Level OptLevel = getCGOptLevel(CodeGenOpts);
 739
 740   llvm::TargetOptions Options;
 741   initTargetOptions(Options, CodeGenOpts, TargetOpts, LangOpts, HSOpts);
 742   TM.reset(TheTarget->createTargetMachine(Triple, TargetOpts.CPU, FeaturesStr,
 743                                           Options, RM, CM, OptLevel));
 744 }
 745
 746 bool EmitAssemblyHelper::AddEmitPasses(legacy::PassManager &CodeGenPasses,
 747                                        BackendAction Action,
 748                                        raw_pwrite_stream &OS,
 749                                        raw_pwrite_stream *DwoOS) {
 750   // Add LibraryInfo.
 751   llvm::Triple TargetTriple(TheModule->getTargetTriple());
 752   std::unique_ptr<TargetLibraryInfoImpl> TLII(
 753       createTLII(TargetTriple, CodeGenOpts));
 754   CodeGenPasses.add(new TargetLibraryInfoWrapperPass(*TLII));
 755
 756   // Normal mode, emit a .s or .o file by running the code generator. Note,
 757   // this also adds codegenerator level optimization passes.
 758   TargetMachine::CodeGenFileType CGFT = getCodeGenFileType(Action);
 759
 760   // Add ObjC ARC final-cleanup optimizations. This is done as part of the
 761   // "codegen" passes so that it isn't run multiple times when there is
 762   // inlining happening.
 763   if (CodeGenOpts.OptimizationLevel > 0)
 764     CodeGenPasses.add(createObjCARCContractPass());
 765
 766   if (TM->addPassesToEmitFile(CodeGenPasses, OS, DwoOS, CGFT,
 767                               /*DisableVerify=*/!CodeGenOpts.VerifyModule)) {
 768     Diags.Report(diag::err_fe_unable_to_interface_with_target);
 769     return false;
 770   }
 771
 772   return true;
 773 }
 774
 775 void EmitAssemblyHelper::EmitAssembly(BackendAction Action,
 776                                       std::unique_ptr<raw_pwrite_stream> OS) {
 777   TimeRegion Region(FrontendTimesIsEnabled ? &CodeGenerationTime : nullptr);
 778
 779   setCommandLineOpts(CodeGenOpts);
 780
 781   bool UsesCodeGen = (Action != Backend_EmitNothing &&
 782                       Action != Backend_EmitBC &&
 783                       Action != Backend_EmitLL);
 784   CreateTargetMachine(UsesCodeGen);
 785
 786   if (UsesCodeGen && !TM)
 787     return;
 788   if (TM)
 789     TheModule->setDataLayout(TM->createDataLayout());
 790
 791   legacy::PassManager PerModulePasses;
 792   PerModulePasses.add(
 793       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
 794
 795   legacy::FunctionPassManager PerFunctionPasses(TheModule);
 796   PerFunctionPasses.add(
 797       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
 798
 799   CreatePasses(PerModulePasses, PerFunctionPasses);
 800
 801   legacy::PassManager CodeGenPasses;
 802   CodeGenPasses.add(
 803       createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
 804
 805   std::unique_ptr<llvm::ToolOutputFile> ThinLinkOS, DwoOS;
 806
 807   switch (Action) {
 808   case Backend_EmitNothing:
 809     break;
 810
 811   case Backend_EmitBC:
 812     if (CodeGenOpts.PrepareForThinLTO && !CodeGenOpts.DisableLLVMPasses) {
 813       if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
 814         ThinLinkOS = openOutputFile(CodeGenOpts.ThinLinkBitcodeFile);
 815         if (!ThinLinkOS)
 816           return;
 817       }
 818       TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
 819                                CodeGenOpts.EnableSplitLTOUnit);
 820       PerModulePasses.add(createWriteThinLTOBitcodePass(
 821           *OS, ThinLinkOS ? &ThinLinkOS->os() : nullptr));
 822     } else {
 823       // Emit a module summary by default for Regular LTO except for ld64
 824       // targets
 825       bool EmitLTOSummary =
 826           (CodeGenOpts.PrepareForLTO &&
 827            !CodeGenOpts.DisableLLVMPasses &&
 828            llvm::Triple(TheModule->getTargetTriple()).getVendor() !=
 829                llvm::Triple::Apple);
 830       if (EmitLTOSummary) {
 831         if (!TheModule->getModuleFlag("ThinLTO"))
 832           TheModule->addModuleFlag(Module::Error, "ThinLTO", uint32_t(0));
 833         TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
 834                                  CodeGenOpts.EnableSplitLTOUnit);
 835       }
 836
 837       PerModulePasses.add(createBitcodeWriterPass(
 838           *OS, CodeGenOpts.EmitLLVMUseLists, EmitLTOSummary));
 839     }
 840     break;
 841
 842   case Backend_EmitLL:
 843     PerModulePasses.add(
 844         createPrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
 845     break;
 846
 847   default:
 848     if (!CodeGenOpts.SplitDwarfFile.empty() &&
 849         (CodeGenOpts.getSplitDwarfMode() == CodeGenOptions::SplitFileFission)) {
 850       DwoOS = openOutputFile(CodeGenOpts.SplitDwarfFile);
 851       if (!DwoOS)
 852         return;
 853     }
 854     if (!AddEmitPasses(CodeGenPasses, Action, *OS,
 855                        DwoOS ? &DwoOS->os() : nullptr))
 856       return;
 857   }
 858
 859   // Before executing passes, print the final values of the LLVM options.
 860   cl::PrintOptionValues();
 861
 862   // Run passes. For now we do all passes at once, but eventually we
 863   // would like to have the option of streaming code generation.
 864
 865   {
 866     PrettyStackTraceString CrashInfo("Per-function optimization");
 867
 868     PerFunctionPasses.doInitialization();
 869     for (Function &F : *TheModule)
 870       if (!F.isDeclaration())
 871         PerFunctionPasses.run(F);
 872     PerFunctionPasses.doFinalization();
 873   }
 874
 875   {
 876     PrettyStackTraceString CrashInfo("Per-module optimization passes");
 877     PerModulePasses.run(*TheModule);
 878   }
 879
 880   {
 881     PrettyStackTraceString CrashInfo("Code generation");
 882     CodeGenPasses.run(*TheModule);
 883   }
 884
 885   if (ThinLinkOS)
 886     ThinLinkOS->keep();
 887   if (DwoOS)
 888     DwoOS->keep();
 889 }
 890
 891 static PassBuilder::OptimizationLevel mapToLevel(const CodeGenOptions &Opts) {
 892   switch (Opts.OptimizationLevel) {
 893   default:
 894     llvm_unreachable("Invalid optimization level!");
 895
 896   case 1:
 897     return PassBuilder::O1;
 898
 899   case 2:
 900     switch (Opts.OptimizeSize) {
 901     default:
 902       llvm_unreachable("Invalid optimization level for size!");
 903
 904     case 0:
 905       return PassBuilder::O2;
 906
 907     case 1:
 908       return PassBuilder::Os;
 909
 910     case 2:
 911       return PassBuilder::Oz;
 912     }
 913
 914   case 3:
 915     return PassBuilder::O3;
 916   }
 917 }
 918
 919 /// A clean version of `EmitAssembly` that uses the new pass manager.
 920 ///
 921 /// Not all features are currently supported in this system, but where
 922 /// necessary it falls back to the legacy pass manager to at least provide
 923 /// basic functionality.
 924 ///
 925 /// This API is planned to have its functionality finished and then to replace
 926 /// `EmitAssembly` at some point in the future when the default switches.
 927 void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
 928     BackendAction Action, std::unique_ptr<raw_pwrite_stream> OS) {
 929   TimeRegion Region(FrontendTimesIsEnabled ? &CodeGenerationTime : nullptr);
 930   setCommandLineOpts(CodeGenOpts);
 931
 932   // The new pass manager always makes a target machine available to passes
 933   // during construction.
 934   CreateTargetMachine(/*MustCreateTM*/ true);
 935   if (!TM)
 936     // This will already be diagnosed, just bail.
 937     return;
 938   TheModule->setDataLayout(TM->createDataLayout());
 939
 940   Optional<PGOOptions> PGOOpt;
 941
 942   if (CodeGenOpts.hasProfileIRInstr())
 943     // -fprofile-generate.
 944     PGOOpt = PGOOptions(CodeGenOpts.InstrProfileOutput.empty()
 945                             ? DefaultProfileGenName
 946                             : CodeGenOpts.InstrProfileOutput,
 947                         "", "", "", true,
 948                         CodeGenOpts.DebugInfoForProfiling);
 949   else if (CodeGenOpts.hasProfileIRUse())
 950     // -fprofile-use.
 951     PGOOpt = PGOOptions("", CodeGenOpts.ProfileInstrumentUsePath, "",
 952                         CodeGenOpts.ProfileRemappingFile, false,
 953                         CodeGenOpts.DebugInfoForProfiling);
 954   else if (!CodeGenOpts.SampleProfileFile.empty())
 955     // -fprofile-sample-use
 956     PGOOpt = PGOOptions("", "", CodeGenOpts.SampleProfileFile,
 957                         CodeGenOpts.ProfileRemappingFile, false,
 958                         CodeGenOpts.DebugInfoForProfiling);
 959   else if (CodeGenOpts.DebugInfoForProfiling)
 960     // -fdebug-info-for-profiling
 961     PGOOpt = PGOOptions("", "", "", "", false, true);
 962
 963   PassBuilder PB(TM.get(), PGOOpt);
 964
 965   LoopAnalysisManager LAM(CodeGenOpts.DebugPassManager);
 966   FunctionAnalysisManager FAM(CodeGenOpts.DebugPassManager);
 967   CGSCCAnalysisManager CGAM(CodeGenOpts.DebugPassManager);
 968   ModuleAnalysisManager MAM(CodeGenOpts.DebugPassManager);
 969
 970   // Register the AA manager first so that our version is the one used.
 971   FAM.registerPass([&] { return PB.buildDefaultAAPipeline(); });
 972
 973   // Register the target library analysis directly and give it a customized
 974   // preset TLI.
 975   Triple TargetTriple(TheModule->getTargetTriple());
 976   std::unique_ptr<TargetLibraryInfoImpl> TLII(
 977       createTLII(TargetTriple, CodeGenOpts));
 978   FAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
 979   MAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
 980
 981   // Register all the basic analyses with the managers.
 982   PB.registerModuleAnalyses(MAM);
 983   PB.registerCGSCCAnalyses(CGAM);
 984   PB.registerFunctionAnalyses(FAM);
 985   PB.registerLoopAnalyses(LAM);
 986   PB.crossRegisterProxies(LAM, FAM, CGAM, MAM);
 987
 988   ModulePassManager MPM(CodeGenOpts.DebugPassManager);
 989
 990   if (!CodeGenOpts.DisableLLVMPasses) {
 991     bool IsThinLTO = CodeGenOpts.PrepareForThinLTO;
 992     bool IsLTO = CodeGenOpts.PrepareForLTO;
 993
 994     if (CodeGenOpts.OptimizationLevel == 0) {
 995       if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts))
 996         MPM.addPass(GCOVProfilerPass(*Options));
 997
 998       // Build a minimal pipeline based on the semantics required by Clang,
 999       // which is just that always inlining occurs.
1000       MPM.addPass(AlwaysInlinerPass());
1001
1002       // At -O0 we directly run necessary sanitizer passes.
1003       if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
1004         MPM.addPass(createModuleToFunctionPassAdaptor(BoundsCheckingPass()));
1005
1006       // Lastly, add semantically necessary passes for LTO.
1007       if (IsLTO || IsThinLTO) {
1008         MPM.addPass(CanonicalizeAliasesPass());
1009         MPM.addPass(NameAnonGlobalPass());
1010       }
1011     } else {
1012       // Map our optimization levels into one of the distinct levels used to
1013       // configure the pipeline.
1014       PassBuilder::OptimizationLevel Level = mapToLevel(CodeGenOpts);
1015
1016       // Register callbacks to schedule sanitizer passes at the appropriate part of
1017       // the pipeline.
1018       if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
1019         PB.registerScalarOptimizerLateEPCallback(
1020             [](FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
1021               FPM.addPass(BoundsCheckingPass());
1022             });
1023       if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts))
1024         PB.registerPipelineStartEPCallback([Options](ModulePassManager &MPM) {
1025           MPM.addPass(GCOVProfilerPass(*Options));
1026         });
1027
1028       if (IsThinLTO) {
1029         MPM = PB.buildThinLTOPreLinkDefaultPipeline(
1030             Level, CodeGenOpts.DebugPassManager);
1031         MPM.addPass(CanonicalizeAliasesPass());
1032         MPM.addPass(NameAnonGlobalPass());
1033       } else if (IsLTO) {
1034         MPM = PB.buildLTOPreLinkDefaultPipeline(Level,
1035                                                 CodeGenOpts.DebugPassManager);
1036         MPM.addPass(CanonicalizeAliasesPass());
1037         MPM.addPass(NameAnonGlobalPass());
1038       } else {
1039         MPM = PB.buildPerModuleDefaultPipeline(Level,
1040                                                CodeGenOpts.DebugPassManager);
1041       }
1042     }
1043   }
1044
1045   // FIXME: We still use the legacy pass manager to do code generation. We
1046   // create that pass manager here and use it as needed below.
1047   legacy::PassManager CodeGenPasses;
1048   bool NeedCodeGen = false;
1049   std::unique_ptr<llvm::ToolOutputFile> ThinLinkOS, DwoOS;
1050
1051   // Append any output we need to the pass manager.
1052   switch (Action) {
1053   case Backend_EmitNothing:
1054     break;
1055
1056   case Backend_EmitBC:
1057     if (CodeGenOpts.PrepareForThinLTO && !CodeGenOpts.DisableLLVMPasses) {
1058       if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
1059         ThinLinkOS = openOutputFile(CodeGenOpts.ThinLinkBitcodeFile);
1060         if (!ThinLinkOS)
1061           return;
1062       }
1063       TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
1064                                CodeGenOpts.EnableSplitLTOUnit);
1065       MPM.addPass(ThinLTOBitcodeWriterPass(*OS, ThinLinkOS ? &ThinLinkOS->os()
1066                                                            : nullptr));
1067     } else {
1068       // Emit a module summary by default for Regular LTO except for ld64
1069       // targets
1070       bool EmitLTOSummary =
1071           (CodeGenOpts.PrepareForLTO &&
1072            !CodeGenOpts.DisableLLVMPasses &&
1073            llvm::Triple(TheModule->getTargetTriple()).getVendor() !=
1074                llvm::Triple::Apple);
1075       if (EmitLTOSummary) {
1076         if (!TheModule->getModuleFlag("ThinLTO"))
1077           TheModule->addModuleFlag(Module::Error, "ThinLTO", uint32_t(0));
1078         TheModule->addModuleFlag(Module::Error, "EnableSplitLTOUnit",
1079                                  CodeGenOpts.EnableSplitLTOUnit);
1080       }
1081       MPM.addPass(
1082           BitcodeWriterPass(*OS, CodeGenOpts.EmitLLVMUseLists, EmitLTOSummary));
1083     }
1084     break;
1085
1086   case Backend_EmitLL:
1087     MPM.addPass(PrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
1088     break;
1089
1090   case Backend_EmitAssembly:
1091   case Backend_EmitMCNull:
1092   case Backend_EmitObj:
1093     NeedCodeGen = true;
1094     CodeGenPasses.add(
1095         createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
1096     if (!CodeGenOpts.SplitDwarfFile.empty()) {
1097       DwoOS = openOutputFile(CodeGenOpts.SplitDwarfFile);
1098       if (!DwoOS)
1099         return;
1100     }
1101     if (!AddEmitPasses(CodeGenPasses, Action, *OS,
1102                        DwoOS ? &DwoOS->os() : nullptr))
1103       // FIXME: Should we handle this error differently?
1104       return;
1105     break;
1106   }
1107
1108   // Before executing passes, print the final values of the LLVM options.
1109   cl::PrintOptionValues();
1110
1111   // Now that we have all of the passes ready, run them.
1112   {
1113     PrettyStackTraceString CrashInfo("Optimizer");
1114     MPM.run(*TheModule, MAM);
1115   }
1116
1117   // Now if needed, run the legacy PM for codegen.
1118   if (NeedCodeGen) {
1119     PrettyStackTraceString CrashInfo("Code generation");
1120     CodeGenPasses.run(*TheModule);
1121   }
1122
1123   if (ThinLinkOS)
1124     ThinLinkOS->keep();
1125   if (DwoOS)
1126     DwoOS->keep();
1127 }
1128
1129 Expected<BitcodeModule> clang::FindThinLTOModule(MemoryBufferRef MBRef) {
1130   Expected<std::vector<BitcodeModule>> BMsOrErr = getBitcodeModuleList(MBRef);
1131   if (!BMsOrErr)
1132     return BMsOrErr.takeError();
1133
1134   // The bitcode file may contain multiple modules, we want the one that is
1135   // marked as being the ThinLTO module.
1136   if (const BitcodeModule *Bm = FindThinLTOModule(*BMsOrErr))
1137     return *Bm;
1138
1139   return make_error<StringError>("Could not find module summary",
1140                                  inconvertibleErrorCode());
1141 }
1142
1143 BitcodeModule *clang::FindThinLTOModule(MutableArrayRef<BitcodeModule> BMs) {
1144   for (BitcodeModule &BM : BMs) {
1145     Expected<BitcodeLTOInfo> LTOInfo = BM.getLTOInfo();
1146     if (LTOInfo && LTOInfo->IsThinLTO)
1147       return &BM;
1148   }
1149   return nullptr;
1150 }
1151
1152 static void runThinLTOBackend(ModuleSummaryIndex *CombinedIndex, Module *M,
1153                               const HeaderSearchOptions &HeaderOpts,
1154                               const CodeGenOptions &CGOpts,
1155                               const clang::TargetOptions &TOpts,
1156                               const LangOptions &LOpts,
1157                               std::unique_ptr<raw_pwrite_stream> OS,
1158                               std::string SampleProfile,
1159                               std::string ProfileRemapping,
1160                               BackendAction Action) {
1161   StringMap<DenseMap<GlobalValue::GUID, GlobalValueSummary *>>
1162       ModuleToDefinedGVSummaries;
1163   CombinedIndex->collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
1164
1165   setCommandLineOpts(CGOpts);
1166
1167   // We can simply import the values mentioned in the combined index, since
1168   // we should only invoke this using the individual indexes written out
1169   // via a WriteIndexesThinBackend.
1170   FunctionImporter::ImportMapTy ImportList;
1171   for (auto &GlobalList : *CombinedIndex) {
1172     // Ignore entries for undefined references.
1173     if (GlobalList.second.SummaryList.empty())
1174       continue;
1175
1176     auto GUID = GlobalList.first;
1177     for (auto &Summary : GlobalList.second.SummaryList) {
1178       // Skip the summaries for the importing module. These are included to
1179       // e.g. record required linkage changes.
1180       if (Summary->modulePath() == M->getModuleIdentifier())
1181         continue;
1182       // Add an entry to provoke importing by thinBackend.
1183       ImportList[Summary->modulePath()].insert(GUID);
1184     }
1185   }
1186
1187   std::vector<std::unique_ptr<llvm::MemoryBuffer>> OwnedImports;
1188   MapVector<llvm::StringRef, llvm::BitcodeModule> ModuleMap;
1189
1190   for (auto &I : ImportList) {
1191     ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> MBOrErr =
1192         llvm::MemoryBuffer::getFile(I.first());
1193     if (!MBOrErr) {
1194       errs() << "Error loading imported file '" << I.first()
1195              << "': " << MBOrErr.getError().message() << "\n";
1196       return;
1197     }
1198
1199     Expected<BitcodeModule> BMOrErr = FindThinLTOModule(**MBOrErr);
1200     if (!BMOrErr) {
1201       handleAllErrors(BMOrErr.takeError(), [&](ErrorInfoBase &EIB) {
1202         errs() << "Error loading imported file '" << I.first()
1203                << "': " << EIB.message() << '\n';
1204       });
1205       return;
1206     }
1207     ModuleMap.insert({I.first(), *BMOrErr});
1208
1209     OwnedImports.push_back(std::move(*MBOrErr));
1210   }
1211   auto AddStream = [&](size_t Task) {
1212     return llvm::make_unique<lto::NativeObjectStream>(std::move(OS));
1213   };
1214   lto::Config Conf;
1215   if (CGOpts.SaveTempsFilePrefix != "") {
1216     if (Error E = Conf.addSaveTemps(CGOpts.SaveTempsFilePrefix + ".",
1217                                     /* UseInputModulePath */ false)) {
1218       handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1219         errs() << "Error setting up ThinLTO save-temps: " << EIB.message()
1220                << '\n';
1221       });
1222     }
1223   }
1224   Conf.CPU = TOpts.CPU;
1225   Conf.CodeModel = getCodeModel(CGOpts);
1226   Conf.MAttrs = TOpts.Features;
1227   Conf.RelocModel = CGOpts.RelocationModel;
1228   Conf.CGOptLevel = getCGOptLevel(CGOpts);
1229   initTargetOptions(Conf.Options, CGOpts, TOpts, LOpts, HeaderOpts);
1230   Conf.SampleProfile = std::move(SampleProfile);
1231   Conf.ProfileRemapping = std::move(ProfileRemapping);
1232   Conf.UseNewPM = CGOpts.ExperimentalNewPassManager;
1233   Conf.DebugPassManager = CGOpts.DebugPassManager;
1234   Conf.RemarksWithHotness = CGOpts.DiagnosticsWithHotness;
1235   Conf.RemarksFilename = CGOpts.OptRecordFile;
1236   Conf.DwoPath = CGOpts.SplitDwarfFile;
1237   switch (Action) {
1238   case Backend_EmitNothing:
1239     Conf.PreCodeGenModuleHook = [](size_t Task, const Module &Mod) {
1240       return false;
1241     };
1242     break;
1243   case Backend_EmitLL:
1244     Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1245       M->print(*OS, nullptr, CGOpts.EmitLLVMUseLists);
1246       return false;
1247     };
1248     break;
1249   case Backend_EmitBC:
1250     Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1251       WriteBitcodeToFile(*M, *OS, CGOpts.EmitLLVMUseLists);
1252       return false;
1253     };
1254     break;
1255   default:
1256     Conf.CGFileType = getCodeGenFileType(Action);
1257     break;
1258   }
1259   if (Error E = thinBackend(
1260           Conf, -1, AddStream, *M, *CombinedIndex, ImportList,
1261           ModuleToDefinedGVSummaries[M->getModuleIdentifier()], ModuleMap)) {
1262     handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1263       errs() << "Error running ThinLTO backend: " << EIB.message() << '\n';
1264     });
1265   }
1266 }
1267
1268 void clang::EmitBackendOutput(DiagnosticsEngine &Diags,
1269                               const HeaderSearchOptions &HeaderOpts,
1270                               const CodeGenOptions &CGOpts,
1271                               const clang::TargetOptions &TOpts,
1272                               const LangOptions &LOpts,
1273                               const llvm::DataLayout &TDesc, Module *M,
1274                               BackendAction Action,
1275                               std::unique_ptr<raw_pwrite_stream> OS) {
1276   std::unique_ptr<llvm::Module> EmptyModule;
1277   if (!CGOpts.ThinLTOIndexFile.empty()) {
1278     // If we are performing a ThinLTO importing compile, load the function index
1279     // into memory and pass it into runThinLTOBackend, which will run the
1280     // function importer and invoke LTO passes.
1281     Expected<std::unique_ptr<ModuleSummaryIndex>> IndexOrErr =
1282         llvm::getModuleSummaryIndexForFile(CGOpts.ThinLTOIndexFile,
1283                                            /*IgnoreEmptyThinLTOIndexFile*/true);
1284     if (!IndexOrErr) {
1285       logAllUnhandledErrors(IndexOrErr.takeError(), errs(),
1286                             "Error loading index file '" +
1287                             CGOpts.ThinLTOIndexFile + "': ");
1288       return;
1289     }
1290     std::unique_ptr<ModuleSummaryIndex> CombinedIndex = std::move(*IndexOrErr);
1291     // A null CombinedIndex means we should skip ThinLTO compilation
1292     // (LLVM will optionally ignore empty index files, returning null instead
1293     // of an error).
1294     if (CombinedIndex) {
1295       if (!CombinedIndex->skipModuleByDistributedBackend()) {
1296         runThinLTOBackend(CombinedIndex.get(), M, HeaderOpts, CGOpts, TOpts,
1297                           LOpts, std::move(OS), CGOpts.SampleProfileFile,
1298                           CGOpts.ProfileRemappingFile, Action);
1299         return;
1300       }
1301       // Distributed indexing detected that nothing from the module is needed
1302       // for the final linking. So we can skip the compilation. We sill need to
1303       // output an empty object file to make sure that a linker does not fail
1304       // trying to read it. Also for some features, like CFI, we must skip
1305       // the compilation as CombinedIndex does not contain all required
1306       // information.
1307       EmptyModule = llvm::make_unique<llvm::Module>("empty", M->getContext());
1308       EmptyModule->setTargetTriple(M->getTargetTriple());
1309       M = EmptyModule.get();
1310     }
1311   }
1312
1313   EmitAssemblyHelper AsmHelper(Diags, HeaderOpts, CGOpts, TOpts, LOpts, M);
1314
1315   if (CGOpts.ExperimentalNewPassManager)
1316     AsmHelper.EmitAssemblyWithNewPassManager(Action, std::move(OS));
1317   else
1318     AsmHelper.EmitAssembly(Action, std::move(OS));
1319
1320   // Verify clang's TargetInfo DataLayout against the LLVM TargetMachine's
1321   // DataLayout.
1322   if (AsmHelper.TM) {
1323     std::string DLDesc = M->getDataLayout().getStringRepresentation();
1324     if (DLDesc != TDesc.getStringRepresentation()) {
1325       unsigned DiagID = Diags.getCustomDiagID(
1326           DiagnosticsEngine::Error, "backend data layout '%0' does not match "
1327                                     "expected target description '%1'");
1328       Diags.Report(DiagID) << DLDesc << TDesc.getStringRepresentation();
1329     }
1330   }
1331 }
1332
1333 static const char* getSectionNameForBitcode(const Triple &T) {
1334   switch (T.getObjectFormat()) {
1335   case Triple::MachO:
1336     return "__LLVM,__bitcode";
1337   case Triple::COFF:
1338   case Triple::ELF:
1339   case Triple::Wasm:
1340   case Triple::UnknownObjectFormat:
1341     return ".llvmbc";
1342   }
1343   llvm_unreachable("Unimplemented ObjectFormatType");
1344 }
1345
1346 static const char* getSectionNameForCommandline(const Triple &T) {
1347   switch (T.getObjectFormat()) {
1348   case Triple::MachO:
1349     return "__LLVM,__cmdline";
1350   case Triple::COFF:
1351   case Triple::ELF:
1352   case Triple::Wasm:
1353   case Triple::UnknownObjectFormat:
1354     return ".llvmcmd";
1355   }
1356   llvm_unreachable("Unimplemented ObjectFormatType");
1357 }
1358
1359 // With -fembed-bitcode, save a copy of the llvm IR as data in the
1360 // __LLVM,__bitcode section.
1361 void clang::EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts,
1362                          llvm::MemoryBufferRef Buf) {
1363   if (CGOpts.getEmbedBitcode() == CodeGenOptions::Embed_Off)
1364     return;
1365
1366   // Save llvm.compiler.used and remote it.
1367   SmallVector<Constant*, 2> UsedArray;
1368   SmallPtrSet<GlobalValue*, 4> UsedGlobals;
1369   Type *UsedElementType = Type::getInt8Ty(M->getContext())->getPointerTo(0);
1370   GlobalVariable *Used = collectUsedGlobalVariables(*M, UsedGlobals, true);
1371   for (auto *GV : UsedGlobals) {
1372     if (GV->getName() != "llvm.embedded.module" &&
1373         GV->getName() != "llvm.cmdline")
1374       UsedArray.push_back(
1375           ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
1376   }
1377   if (Used)
1378     Used->eraseFromParent();
1379
1380   // Embed the bitcode for the llvm module.
1381   std::string Data;
1382   ArrayRef<uint8_t> ModuleData;
1383   Triple T(M->getTargetTriple());
1384   // Create a constant that contains the bitcode.
1385   // In case of embedding a marker, ignore the input Buf and use the empty
1386   // ArrayRef. It is also legal to create a bitcode marker even Buf is empty.
1387   if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Marker) {
1388     if (!isBitcode((const unsigned char *)Buf.getBufferStart(),
1389                    (const unsigned char *)Buf.getBufferEnd())) {
1390       // If the input is LLVM Assembly, bitcode is produced by serializing
1391       // the module. Use-lists order need to be perserved in this case.
1392       llvm::raw_string_ostream OS(Data);
1393       llvm::WriteBitcodeToFile(*M, OS, /* ShouldPreserveUseListOrder */ true);
1394       ModuleData =
1395           ArrayRef<uint8_t>((const uint8_t *)OS.str().data(), OS.str().size());
1396     } else
1397       // If the input is LLVM bitcode, write the input byte stream directly.
1398       ModuleData = ArrayRef<uint8_t>((const uint8_t *)Buf.getBufferStart(),
1399                                      Buf.getBufferSize());
1400   }
1401   llvm::Constant *ModuleConstant =
1402       llvm::ConstantDataArray::get(M->getContext(), ModuleData);
1403   llvm::GlobalVariable *GV = new llvm::GlobalVariable(
1404       *M, ModuleConstant->getType(), true, llvm::GlobalValue::PrivateLinkage,
1405       ModuleConstant);
1406   GV->setSection(getSectionNameForBitcode(T));
1407   UsedArray.push_back(
1408       ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
1409   if (llvm::GlobalVariable *Old =
1410           M->getGlobalVariable("llvm.embedded.module", true)) {
1411     assert(Old->hasOneUse() &&
1412            "llvm.embedded.module can only be used once in llvm.compiler.used");
1413     GV->takeName(Old);
1414     Old->eraseFromParent();
1415   } else {
1416     GV->setName("llvm.embedded.module");
1417   }
1418
1419   // Skip if only bitcode needs to be embedded.
1420   if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Bitcode) {
1421     // Embed command-line options.
1422     ArrayRef<uint8_t> CmdData(const_cast<uint8_t *>(CGOpts.CmdArgs.data()),
1423                               CGOpts.CmdArgs.size());
1424     llvm::Constant *CmdConstant =
1425       llvm::ConstantDataArray::get(M->getContext(), CmdData);
1426     GV = new llvm::GlobalVariable(*M, CmdConstant->getType(), true,
1427                                   llvm::GlobalValue::PrivateLinkage,
1428                                   CmdConstant);
1429     GV->setSection(getSectionNameForCommandline(T));
1430     UsedArray.push_back(
1431         ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
1432     if (llvm::GlobalVariable *Old =
1433             M->getGlobalVariable("llvm.cmdline", true)) {
1434       assert(Old->hasOneUse() &&
1435              "llvm.cmdline can only be used once in llvm.compiler.used");
1436       GV->takeName(Old);
1437       Old->eraseFromParent();
1438     } else {
1439       GV->setName("llvm.cmdline");
1440     }
1441   }
1442
1443   if (UsedArray.empty())
1444     return;
1445
1446   // Recreate llvm.compiler.used.
1447   ArrayType *ATy = ArrayType::get(UsedElementType, UsedArray.size());
1448   auto *NewUsed = new GlobalVariable(
1449       *M, ATy, false, llvm::GlobalValue::AppendingLinkage,
1450       llvm::ConstantArray::get(ATy, UsedArray), "llvm.compiler.used");
1451   NewUsed->setSection("llvm.metadata");
1452 }