clang  6.0.0svn
BackendUtil.cpp
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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 
11 #include "clang/Basic/Diagnostic.h"
16 #include "clang/Frontend/Utils.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/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/Support/CommandLine.h"
40 #include "llvm/Support/MemoryBuffer.h"
41 #include "llvm/Support/PrettyStackTrace.h"
42 #include "llvm/Support/TargetRegistry.h"
43 #include "llvm/Support/Timer.h"
44 #include "llvm/Support/raw_ostream.h"
45 #include "llvm/Target/TargetMachine.h"
46 #include "llvm/Target/TargetOptions.h"
47 #include "llvm/CodeGen/TargetSubtargetInfo.h"
48 #include "llvm/Transforms/Coroutines.h"
49 #include "llvm/Transforms/IPO.h"
50 #include "llvm/Transforms/IPO/AlwaysInliner.h"
51 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
52 #include "llvm/Transforms/IPO/ThinLTOBitcodeWriter.h"
53 #include "llvm/Transforms/Instrumentation.h"
54 #include "llvm/Transforms/Instrumentation/BoundsChecking.h"
55 #include "llvm/Transforms/ObjCARC.h"
56 #include "llvm/Transforms/Scalar.h"
57 #include "llvm/Transforms/Scalar/GVN.h"
58 #include "llvm/Transforms/Utils/NameAnonGlobals.h"
59 #include "llvm/Transforms/Utils/SymbolRewriter.h"
60 #include <memory>
61 using namespace clang;
62 using namespace llvm;
63 
64 namespace {
65 
66 // Default filename used for profile generation.
67 static constexpr StringLiteral DefaultProfileGenName = "default_%m.profraw";
68 
69 class EmitAssemblyHelper {
70  DiagnosticsEngine &Diags;
71  const HeaderSearchOptions &HSOpts;
72  const CodeGenOptions &CodeGenOpts;
73  const clang::TargetOptions &TargetOpts;
74  const LangOptions &LangOpts;
75  Module *TheModule;
76 
77  Timer CodeGenerationTime;
78 
79  std::unique_ptr<raw_pwrite_stream> OS;
80 
81  TargetIRAnalysis getTargetIRAnalysis() const {
82  if (TM)
83  return TM->getTargetIRAnalysis();
84 
85  return TargetIRAnalysis();
86  }
87 
88  void CreatePasses(legacy::PassManager &MPM, legacy::FunctionPassManager &FPM);
89 
90  /// Generates the TargetMachine.
91  /// Leaves TM unchanged if it is unable to create the target machine.
92  /// Some of our clang tests specify triples which are not built
93  /// into clang. This is okay because these tests check the generated
94  /// IR, and they require DataLayout which depends on the triple.
95  /// In this case, we allow this method to fail and not report an error.
96  /// When MustCreateTM is used, we print an error if we are unable to load
97  /// the requested target.
98  void CreateTargetMachine(bool MustCreateTM);
99 
100  /// Add passes necessary to emit assembly or LLVM IR.
101  ///
102  /// \return True on success.
103  bool AddEmitPasses(legacy::PassManager &CodeGenPasses, BackendAction Action,
104  raw_pwrite_stream &OS);
105 
106 public:
107  EmitAssemblyHelper(DiagnosticsEngine &_Diags,
108  const HeaderSearchOptions &HeaderSearchOpts,
109  const CodeGenOptions &CGOpts,
110  const clang::TargetOptions &TOpts,
111  const LangOptions &LOpts, Module *M)
112  : Diags(_Diags), HSOpts(HeaderSearchOpts), CodeGenOpts(CGOpts),
113  TargetOpts(TOpts), LangOpts(LOpts), TheModule(M),
114  CodeGenerationTime("codegen", "Code Generation Time") {}
115 
116  ~EmitAssemblyHelper() {
117  if (CodeGenOpts.DisableFree)
118  BuryPointer(std::move(TM));
119  }
120 
121  std::unique_ptr<TargetMachine> TM;
122 
123  void EmitAssembly(BackendAction Action,
124  std::unique_ptr<raw_pwrite_stream> OS);
125 
126  void EmitAssemblyWithNewPassManager(BackendAction Action,
127  std::unique_ptr<raw_pwrite_stream> OS);
128 };
129 
130 // We need this wrapper to access LangOpts and CGOpts from extension functions
131 // that we add to the PassManagerBuilder.
132 class PassManagerBuilderWrapper : public PassManagerBuilder {
133 public:
134  PassManagerBuilderWrapper(const Triple &TargetTriple,
135  const CodeGenOptions &CGOpts,
136  const LangOptions &LangOpts)
137  : PassManagerBuilder(), TargetTriple(TargetTriple), CGOpts(CGOpts),
138  LangOpts(LangOpts) {}
139  const Triple &getTargetTriple() const { return TargetTriple; }
140  const CodeGenOptions &getCGOpts() const { return CGOpts; }
141  const LangOptions &getLangOpts() const { return LangOpts; }
142 
143 private:
144  const Triple &TargetTriple;
145  const CodeGenOptions &CGOpts;
146  const LangOptions &LangOpts;
147 };
148 }
149 
150 static void addObjCARCAPElimPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
151  if (Builder.OptLevel > 0)
152  PM.add(createObjCARCAPElimPass());
153 }
154 
155 static void addObjCARCExpandPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
156  if (Builder.OptLevel > 0)
157  PM.add(createObjCARCExpandPass());
158 }
159 
160 static void addObjCARCOptPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
161  if (Builder.OptLevel > 0)
162  PM.add(createObjCARCOptPass());
163 }
164 
165 static void addAddDiscriminatorsPass(const PassManagerBuilder &Builder,
166  legacy::PassManagerBase &PM) {
167  PM.add(createAddDiscriminatorsPass());
168 }
169 
170 static void addBoundsCheckingPass(const PassManagerBuilder &Builder,
171  legacy::PassManagerBase &PM) {
172  PM.add(createBoundsCheckingLegacyPass());
173 }
174 
175 static void addSanitizerCoveragePass(const PassManagerBuilder &Builder,
176  legacy::PassManagerBase &PM) {
177  const PassManagerBuilderWrapper &BuilderWrapper =
178  static_cast<const PassManagerBuilderWrapper&>(Builder);
179  const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
180  SanitizerCoverageOptions Opts;
181  Opts.CoverageType =
182  static_cast<SanitizerCoverageOptions::Type>(CGOpts.SanitizeCoverageType);
183  Opts.IndirectCalls = CGOpts.SanitizeCoverageIndirectCalls;
184  Opts.TraceBB = CGOpts.SanitizeCoverageTraceBB;
185  Opts.TraceCmp = CGOpts.SanitizeCoverageTraceCmp;
186  Opts.TraceDiv = CGOpts.SanitizeCoverageTraceDiv;
187  Opts.TraceGep = CGOpts.SanitizeCoverageTraceGep;
188  Opts.Use8bitCounters = CGOpts.SanitizeCoverage8bitCounters;
189  Opts.TracePC = CGOpts.SanitizeCoverageTracePC;
190  Opts.TracePCGuard = CGOpts.SanitizeCoverageTracePCGuard;
191  Opts.NoPrune = CGOpts.SanitizeCoverageNoPrune;
192  Opts.Inline8bitCounters = CGOpts.SanitizeCoverageInline8bitCounters;
193  Opts.PCTable = CGOpts.SanitizeCoveragePCTable;
194  Opts.StackDepth = CGOpts.SanitizeCoverageStackDepth;
195  PM.add(createSanitizerCoverageModulePass(Opts));
196 }
197 
198 // Check if ASan should use GC-friendly instrumentation for globals.
199 // First of all, there is no point if -fdata-sections is off (expect for MachO,
200 // where this is not a factor). Also, on ELF this feature requires an assembler
201 // extension that only works with -integrated-as at the moment.
202 static bool asanUseGlobalsGC(const Triple &T, const CodeGenOptions &CGOpts) {
203  if (!CGOpts.SanitizeAddressGlobalsDeadStripping)
204  return false;
205  switch (T.getObjectFormat()) {
206  case Triple::MachO:
207  case Triple::COFF:
208  return true;
209  case Triple::ELF:
210  return CGOpts.DataSections && !CGOpts.DisableIntegratedAS;
211  default:
212  return false;
213  }
214 }
215 
216 static void addAddressSanitizerPasses(const PassManagerBuilder &Builder,
217  legacy::PassManagerBase &PM) {
218  const PassManagerBuilderWrapper &BuilderWrapper =
219  static_cast<const PassManagerBuilderWrapper&>(Builder);
220  const Triple &T = BuilderWrapper.getTargetTriple();
221  const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
222  bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Address);
223  bool UseAfterScope = CGOpts.SanitizeAddressUseAfterScope;
224  bool UseGlobalsGC = asanUseGlobalsGC(T, CGOpts);
225  PM.add(createAddressSanitizerFunctionPass(/*CompileKernel*/ false, Recover,
226  UseAfterScope));
227  PM.add(createAddressSanitizerModulePass(/*CompileKernel*/ false, Recover,
228  UseGlobalsGC));
229 }
230 
231 static void addKernelAddressSanitizerPasses(const PassManagerBuilder &Builder,
232  legacy::PassManagerBase &PM) {
233  PM.add(createAddressSanitizerFunctionPass(
234  /*CompileKernel*/ true,
235  /*Recover*/ true, /*UseAfterScope*/ false));
236  PM.add(createAddressSanitizerModulePass(/*CompileKernel*/true,
237  /*Recover*/true));
238 }
239 
240 static void addHWAddressSanitizerPasses(const PassManagerBuilder &Builder,
241  legacy::PassManagerBase &PM) {
242  PM.add(createHWAddressSanitizerPass());
243 }
244 
245 static void addMemorySanitizerPass(const PassManagerBuilder &Builder,
246  legacy::PassManagerBase &PM) {
247  const PassManagerBuilderWrapper &BuilderWrapper =
248  static_cast<const PassManagerBuilderWrapper&>(Builder);
249  const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
250  int TrackOrigins = CGOpts.SanitizeMemoryTrackOrigins;
251  bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Memory);
252  PM.add(createMemorySanitizerPass(TrackOrigins, Recover));
253 
254  // MemorySanitizer inserts complex instrumentation that mostly follows
255  // the logic of the original code, but operates on "shadow" values.
256  // It can benefit from re-running some general purpose optimization passes.
257  if (Builder.OptLevel > 0) {
258  PM.add(createEarlyCSEPass());
259  PM.add(createReassociatePass());
260  PM.add(createLICMPass());
261  PM.add(createGVNPass());
262  PM.add(createInstructionCombiningPass());
263  PM.add(createDeadStoreEliminationPass());
264  }
265 }
266 
267 static void addThreadSanitizerPass(const PassManagerBuilder &Builder,
268  legacy::PassManagerBase &PM) {
269  PM.add(createThreadSanitizerPass());
270 }
271 
272 static void addDataFlowSanitizerPass(const PassManagerBuilder &Builder,
273  legacy::PassManagerBase &PM) {
274  const PassManagerBuilderWrapper &BuilderWrapper =
275  static_cast<const PassManagerBuilderWrapper&>(Builder);
276  const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
277  PM.add(createDataFlowSanitizerPass(LangOpts.SanitizerBlacklistFiles));
278 }
279 
280 static void addEfficiencySanitizerPass(const PassManagerBuilder &Builder,
281  legacy::PassManagerBase &PM) {
282  const PassManagerBuilderWrapper &BuilderWrapper =
283  static_cast<const PassManagerBuilderWrapper&>(Builder);
284  const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
285  EfficiencySanitizerOptions Opts;
286  if (LangOpts.Sanitize.has(SanitizerKind::EfficiencyCacheFrag))
287  Opts.ToolType = EfficiencySanitizerOptions::ESAN_CacheFrag;
288  else if (LangOpts.Sanitize.has(SanitizerKind::EfficiencyWorkingSet))
289  Opts.ToolType = EfficiencySanitizerOptions::ESAN_WorkingSet;
290  PM.add(createEfficiencySanitizerPass(Opts));
291 }
292 
293 static TargetLibraryInfoImpl *createTLII(llvm::Triple &TargetTriple,
294  const CodeGenOptions &CodeGenOpts) {
295  TargetLibraryInfoImpl *TLII = new TargetLibraryInfoImpl(TargetTriple);
296  if (!CodeGenOpts.SimplifyLibCalls)
297  TLII->disableAllFunctions();
298  else {
299  // Disable individual libc/libm calls in TargetLibraryInfo.
300  LibFunc F;
301  for (auto &FuncName : CodeGenOpts.getNoBuiltinFuncs())
302  if (TLII->getLibFunc(FuncName, F))
303  TLII->setUnavailable(F);
304  }
305 
306  switch (CodeGenOpts.getVecLib()) {
308  TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::Accelerate);
309  break;
311  TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::SVML);
312  break;
313  default:
314  break;
315  }
316  return TLII;
317 }
318 
319 static void addSymbolRewriterPass(const CodeGenOptions &Opts,
320  legacy::PassManager *MPM) {
321  llvm::SymbolRewriter::RewriteDescriptorList DL;
322 
323  llvm::SymbolRewriter::RewriteMapParser MapParser;
324  for (const auto &MapFile : Opts.RewriteMapFiles)
325  MapParser.parse(MapFile, &DL);
326 
327  MPM->add(createRewriteSymbolsPass(DL));
328 }
329 
330 static CodeGenOpt::Level getCGOptLevel(const CodeGenOptions &CodeGenOpts) {
331  switch (CodeGenOpts.OptimizationLevel) {
332  default:
333  llvm_unreachable("Invalid optimization level!");
334  case 0:
335  return CodeGenOpt::None;
336  case 1:
337  return CodeGenOpt::Less;
338  case 2:
339  return CodeGenOpt::Default; // O2/Os/Oz
340  case 3:
341  return CodeGenOpt::Aggressive;
342  }
343 }
344 
346 getCodeModel(const CodeGenOptions &CodeGenOpts) {
347  unsigned CodeModel = llvm::StringSwitch<unsigned>(CodeGenOpts.CodeModel)
348  .Case("small", llvm::CodeModel::Small)
349  .Case("kernel", llvm::CodeModel::Kernel)
350  .Case("medium", llvm::CodeModel::Medium)
351  .Case("large", llvm::CodeModel::Large)
352  .Case("default", ~1u)
353  .Default(~0u);
354  assert(CodeModel != ~0u && "invalid code model!");
355  if (CodeModel == ~1u)
356  return None;
357  return static_cast<llvm::CodeModel::Model>(CodeModel);
358 }
359 
360 static llvm::Reloc::Model getRelocModel(const CodeGenOptions &CodeGenOpts) {
361  // Keep this synced with the equivalent code in
362  // lib/Frontend/CompilerInvocation.cpp
364  RM = llvm::StringSwitch<llvm::Reloc::Model>(CodeGenOpts.RelocationModel)
365  .Case("static", llvm::Reloc::Static)
366  .Case("pic", llvm::Reloc::PIC_)
367  .Case("ropi", llvm::Reloc::ROPI)
368  .Case("rwpi", llvm::Reloc::RWPI)
369  .Case("ropi-rwpi", llvm::Reloc::ROPI_RWPI)
370  .Case("dynamic-no-pic", llvm::Reloc::DynamicNoPIC);
371  assert(RM.hasValue() && "invalid PIC model!");
372  return *RM;
373 }
374 
375 static TargetMachine::CodeGenFileType getCodeGenFileType(BackendAction Action) {
376  if (Action == Backend_EmitObj)
377  return TargetMachine::CGFT_ObjectFile;
378  else if (Action == Backend_EmitMCNull)
379  return TargetMachine::CGFT_Null;
380  else {
381  assert(Action == Backend_EmitAssembly && "Invalid action!");
382  return TargetMachine::CGFT_AssemblyFile;
383  }
384 }
385 
386 static void initTargetOptions(llvm::TargetOptions &Options,
387  const CodeGenOptions &CodeGenOpts,
388  const clang::TargetOptions &TargetOpts,
389  const LangOptions &LangOpts,
390  const HeaderSearchOptions &HSOpts) {
391  Options.ThreadModel =
392  llvm::StringSwitch<llvm::ThreadModel::Model>(CodeGenOpts.ThreadModel)
393  .Case("posix", llvm::ThreadModel::POSIX)
394  .Case("single", llvm::ThreadModel::Single);
395 
396  // Set float ABI type.
397  assert((CodeGenOpts.FloatABI == "soft" || CodeGenOpts.FloatABI == "softfp" ||
398  CodeGenOpts.FloatABI == "hard" || CodeGenOpts.FloatABI.empty()) &&
399  "Invalid Floating Point ABI!");
400  Options.FloatABIType =
401  llvm::StringSwitch<llvm::FloatABI::ABIType>(CodeGenOpts.FloatABI)
402  .Case("soft", llvm::FloatABI::Soft)
403  .Case("softfp", llvm::FloatABI::Soft)
404  .Case("hard", llvm::FloatABI::Hard)
405  .Default(llvm::FloatABI::Default);
406 
407  // Set FP fusion mode.
408  switch (LangOpts.getDefaultFPContractMode()) {
410  // Preserve any contraction performed by the front-end. (Strict performs
411  // splitting of the muladd instrinsic in the backend.)
412  Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
413  break;
414  case LangOptions::FPC_On:
415  Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
416  break;
418  Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
419  break;
420  }
421 
422  Options.UseInitArray = CodeGenOpts.UseInitArray;
423  Options.DisableIntegratedAS = CodeGenOpts.DisableIntegratedAS;
424  Options.CompressDebugSections = CodeGenOpts.getCompressDebugSections();
425  Options.RelaxELFRelocations = CodeGenOpts.RelaxELFRelocations;
426 
427  // Set EABI version.
428  Options.EABIVersion = TargetOpts.EABIVersion;
429 
430  if (LangOpts.SjLjExceptions)
431  Options.ExceptionModel = llvm::ExceptionHandling::SjLj;
432  if (LangOpts.SEHExceptions)
433  Options.ExceptionModel = llvm::ExceptionHandling::WinEH;
434  if (LangOpts.DWARFExceptions)
435  Options.ExceptionModel = llvm::ExceptionHandling::DwarfCFI;
436 
437  Options.NoInfsFPMath = CodeGenOpts.NoInfsFPMath;
438  Options.NoNaNsFPMath = CodeGenOpts.NoNaNsFPMath;
439  Options.NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS;
440  Options.UnsafeFPMath = CodeGenOpts.UnsafeFPMath;
441  Options.StackAlignmentOverride = CodeGenOpts.StackAlignment;
442  Options.FunctionSections = CodeGenOpts.FunctionSections;
443  Options.DataSections = CodeGenOpts.DataSections;
444  Options.UniqueSectionNames = CodeGenOpts.UniqueSectionNames;
445  Options.EmulatedTLS = CodeGenOpts.EmulatedTLS;
446  Options.DebuggerTuning = CodeGenOpts.getDebuggerTuning();
447 
448  if (CodeGenOpts.EnableSplitDwarf)
449  Options.MCOptions.SplitDwarfFile = CodeGenOpts.SplitDwarfFile;
450  Options.MCOptions.MCRelaxAll = CodeGenOpts.RelaxAll;
451  Options.MCOptions.MCSaveTempLabels = CodeGenOpts.SaveTempLabels;
452  Options.MCOptions.MCUseDwarfDirectory = !CodeGenOpts.NoDwarfDirectoryAsm;
453  Options.MCOptions.MCNoExecStack = CodeGenOpts.NoExecStack;
454  Options.MCOptions.MCIncrementalLinkerCompatible =
455  CodeGenOpts.IncrementalLinkerCompatible;
456  Options.MCOptions.MCPIECopyRelocations = CodeGenOpts.PIECopyRelocations;
457  Options.MCOptions.MCFatalWarnings = CodeGenOpts.FatalWarnings;
458  Options.MCOptions.AsmVerbose = CodeGenOpts.AsmVerbose;
459  Options.MCOptions.PreserveAsmComments = CodeGenOpts.PreserveAsmComments;
460  Options.MCOptions.ABIName = TargetOpts.ABI;
461  for (const auto &Entry : HSOpts.UserEntries)
462  if (!Entry.IsFramework &&
463  (Entry.Group == frontend::IncludeDirGroup::Quoted ||
464  Entry.Group == frontend::IncludeDirGroup::Angled ||
465  Entry.Group == frontend::IncludeDirGroup::System))
466  Options.MCOptions.IASSearchPaths.push_back(
467  Entry.IgnoreSysRoot ? Entry.Path : HSOpts.Sysroot + Entry.Path);
468 }
469 
470 void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
471  legacy::FunctionPassManager &FPM) {
472  // Handle disabling of all LLVM passes, where we want to preserve the
473  // internal module before any optimization.
474  if (CodeGenOpts.DisableLLVMPasses)
475  return;
476 
477  // Figure out TargetLibraryInfo. This needs to be added to MPM and FPM
478  // manually (and not via PMBuilder), since some passes (eg. InstrProfiling)
479  // are inserted before PMBuilder ones - they'd get the default-constructed
480  // TLI with an unknown target otherwise.
481  Triple TargetTriple(TheModule->getTargetTriple());
482  std::unique_ptr<TargetLibraryInfoImpl> TLII(
483  createTLII(TargetTriple, CodeGenOpts));
484 
485  PassManagerBuilderWrapper PMBuilder(TargetTriple, CodeGenOpts, LangOpts);
486 
487  // At O0 and O1 we only run the always inliner which is more efficient. At
488  // higher optimization levels we run the normal inliner.
489  if (CodeGenOpts.OptimizationLevel <= 1) {
490  bool InsertLifetimeIntrinsics = (CodeGenOpts.OptimizationLevel != 0 &&
491  !CodeGenOpts.DisableLifetimeMarkers);
492  PMBuilder.Inliner = createAlwaysInlinerLegacyPass(InsertLifetimeIntrinsics);
493  } else {
494  // We do not want to inline hot callsites for SamplePGO module-summary build
495  // because profile annotation will happen again in ThinLTO backend, and we
496  // want the IR of the hot path to match the profile.
497  PMBuilder.Inliner = createFunctionInliningPass(
498  CodeGenOpts.OptimizationLevel, CodeGenOpts.OptimizeSize,
499  (!CodeGenOpts.SampleProfileFile.empty() &&
500  CodeGenOpts.EmitSummaryIndex));
501  }
502 
503  PMBuilder.OptLevel = CodeGenOpts.OptimizationLevel;
504  PMBuilder.SizeLevel = CodeGenOpts.OptimizeSize;
505  PMBuilder.SLPVectorize = CodeGenOpts.VectorizeSLP;
506  PMBuilder.LoopVectorize = CodeGenOpts.VectorizeLoop;
507 
508  PMBuilder.DisableUnrollLoops = !CodeGenOpts.UnrollLoops;
509  PMBuilder.MergeFunctions = CodeGenOpts.MergeFunctions;
510  PMBuilder.PrepareForThinLTO = CodeGenOpts.EmitSummaryIndex;
511  PMBuilder.PrepareForLTO = CodeGenOpts.PrepareForLTO;
512  PMBuilder.RerollLoops = CodeGenOpts.RerollLoops;
513 
514  MPM.add(new TargetLibraryInfoWrapperPass(*TLII));
515 
516  if (TM)
517  TM->adjustPassManager(PMBuilder);
518 
519  if (CodeGenOpts.DebugInfoForProfiling ||
520  !CodeGenOpts.SampleProfileFile.empty())
521  PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
523 
524  // In ObjC ARC mode, add the main ARC optimization passes.
525  if (LangOpts.ObjCAutoRefCount) {
526  PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
528  PMBuilder.addExtension(PassManagerBuilder::EP_ModuleOptimizerEarly,
530  PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
532  }
533 
534  if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds)) {
535  PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
537  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
539  }
540 
541  if (CodeGenOpts.SanitizeCoverageType ||
542  CodeGenOpts.SanitizeCoverageIndirectCalls ||
543  CodeGenOpts.SanitizeCoverageTraceCmp) {
544  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
546  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
548  }
549 
550  if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
551  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
553  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
555  }
556 
557  if (LangOpts.Sanitize.has(SanitizerKind::KernelAddress)) {
558  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
560  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
562  }
563 
564  if (LangOpts.Sanitize.has(SanitizerKind::HWAddress)) {
565  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
567  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
569  }
570 
571  if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
572  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
574  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
576  }
577 
578  if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
579  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
581  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
583  }
584 
585  if (LangOpts.Sanitize.has(SanitizerKind::DataFlow)) {
586  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
588  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
590  }
591 
592  if (LangOpts.CoroutinesTS)
593  addCoroutinePassesToExtensionPoints(PMBuilder);
594 
595  if (LangOpts.Sanitize.hasOneOf(SanitizerKind::Efficiency)) {
596  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
598  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
600  }
601 
602  // Set up the per-function pass manager.
603  FPM.add(new TargetLibraryInfoWrapperPass(*TLII));
604  if (CodeGenOpts.VerifyModule)
605  FPM.add(createVerifierPass());
606 
607  // Set up the per-module pass manager.
608  if (!CodeGenOpts.RewriteMapFiles.empty())
609  addSymbolRewriterPass(CodeGenOpts, &MPM);
610 
611  if (!CodeGenOpts.DisableGCov &&
612  (CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes)) {
613  // Not using 'GCOVOptions::getDefault' allows us to avoid exiting if
614  // LLVM's -default-gcov-version flag is set to something invalid.
615  GCOVOptions Options;
616  Options.EmitNotes = CodeGenOpts.EmitGcovNotes;
617  Options.EmitData = CodeGenOpts.EmitGcovArcs;
618  memcpy(Options.Version, CodeGenOpts.CoverageVersion, 4);
619  Options.UseCfgChecksum = CodeGenOpts.CoverageExtraChecksum;
620  Options.NoRedZone = CodeGenOpts.DisableRedZone;
621  Options.FunctionNamesInData =
622  !CodeGenOpts.CoverageNoFunctionNamesInData;
623  Options.ExitBlockBeforeBody = CodeGenOpts.CoverageExitBlockBeforeBody;
624  MPM.add(createGCOVProfilerPass(Options));
625  if (CodeGenOpts.getDebugInfo() == codegenoptions::NoDebugInfo)
626  MPM.add(createStripSymbolsPass(true));
627  }
628 
629  if (CodeGenOpts.hasProfileClangInstr()) {
630  InstrProfOptions Options;
631  Options.NoRedZone = CodeGenOpts.DisableRedZone;
632  Options.InstrProfileOutput = CodeGenOpts.InstrProfileOutput;
633  MPM.add(createInstrProfilingLegacyPass(Options));
634  }
635  if (CodeGenOpts.hasProfileIRInstr()) {
636  PMBuilder.EnablePGOInstrGen = true;
637  if (!CodeGenOpts.InstrProfileOutput.empty())
638  PMBuilder.PGOInstrGen = CodeGenOpts.InstrProfileOutput;
639  else
640  PMBuilder.PGOInstrGen = DefaultProfileGenName;
641  }
642  if (CodeGenOpts.hasProfileIRUse())
643  PMBuilder.PGOInstrUse = CodeGenOpts.ProfileInstrumentUsePath;
644 
645  if (!CodeGenOpts.SampleProfileFile.empty())
646  PMBuilder.PGOSampleUse = CodeGenOpts.SampleProfileFile;
647 
648  PMBuilder.populateFunctionPassManager(FPM);
649  PMBuilder.populateModulePassManager(MPM);
650 }
651 
652 static void setCommandLineOpts(const CodeGenOptions &CodeGenOpts) {
653  SmallVector<const char *, 16> BackendArgs;
654  BackendArgs.push_back("clang"); // Fake program name.
655  if (!CodeGenOpts.DebugPass.empty()) {
656  BackendArgs.push_back("-debug-pass");
657  BackendArgs.push_back(CodeGenOpts.DebugPass.c_str());
658  }
659  if (!CodeGenOpts.LimitFloatPrecision.empty()) {
660  BackendArgs.push_back("-limit-float-precision");
661  BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
662  }
663  for (const std::string &BackendOption : CodeGenOpts.BackendOptions)
664  BackendArgs.push_back(BackendOption.c_str());
665  BackendArgs.push_back(nullptr);
666  llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
667  BackendArgs.data());
668 }
669 
670 void EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
671  // Create the TargetMachine for generating code.
672  std::string Error;
673  std::string Triple = TheModule->getTargetTriple();
674  const llvm::Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error);
675  if (!TheTarget) {
676  if (MustCreateTM)
677  Diags.Report(diag::err_fe_unable_to_create_target) << Error;
678  return;
679  }
680 
682  std::string FeaturesStr =
683  llvm::join(TargetOpts.Features.begin(), TargetOpts.Features.end(), ",");
684  llvm::Reloc::Model RM = getRelocModel(CodeGenOpts);
685  CodeGenOpt::Level OptLevel = getCGOptLevel(CodeGenOpts);
686 
687  llvm::TargetOptions Options;
688  initTargetOptions(Options, CodeGenOpts, TargetOpts, LangOpts, HSOpts);
689  TM.reset(TheTarget->createTargetMachine(Triple, TargetOpts.CPU, FeaturesStr,
690  Options, RM, CM, OptLevel));
691 }
692 
693 bool EmitAssemblyHelper::AddEmitPasses(legacy::PassManager &CodeGenPasses,
694  BackendAction Action,
695  raw_pwrite_stream &OS) {
696  // Add LibraryInfo.
697  llvm::Triple TargetTriple(TheModule->getTargetTriple());
698  std::unique_ptr<TargetLibraryInfoImpl> TLII(
699  createTLII(TargetTriple, CodeGenOpts));
700  CodeGenPasses.add(new TargetLibraryInfoWrapperPass(*TLII));
701 
702  // Normal mode, emit a .s or .o file by running the code generator. Note,
703  // this also adds codegenerator level optimization passes.
704  TargetMachine::CodeGenFileType CGFT = getCodeGenFileType(Action);
705 
706  // Add ObjC ARC final-cleanup optimizations. This is done as part of the
707  // "codegen" passes so that it isn't run multiple times when there is
708  // inlining happening.
709  if (CodeGenOpts.OptimizationLevel > 0)
710  CodeGenPasses.add(createObjCARCContractPass());
711 
712  if (TM->addPassesToEmitFile(CodeGenPasses, OS, CGFT,
713  /*DisableVerify=*/!CodeGenOpts.VerifyModule)) {
714  Diags.Report(diag::err_fe_unable_to_interface_with_target);
715  return false;
716  }
717 
718  return true;
719 }
720 
722  std::unique_ptr<raw_pwrite_stream> OS) {
723  TimeRegion Region(llvm::TimePassesIsEnabled ? &CodeGenerationTime : nullptr);
724 
725  setCommandLineOpts(CodeGenOpts);
726 
727  bool UsesCodeGen = (Action != Backend_EmitNothing &&
728  Action != Backend_EmitBC &&
729  Action != Backend_EmitLL);
730  CreateTargetMachine(UsesCodeGen);
731 
732  if (UsesCodeGen && !TM)
733  return;
734  if (TM)
735  TheModule->setDataLayout(TM->createDataLayout());
736 
737  legacy::PassManager PerModulePasses;
738  PerModulePasses.add(
739  createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
740 
741  legacy::FunctionPassManager PerFunctionPasses(TheModule);
742  PerFunctionPasses.add(
743  createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
744 
745  CreatePasses(PerModulePasses, PerFunctionPasses);
746 
747  legacy::PassManager CodeGenPasses;
748  CodeGenPasses.add(
749  createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
750 
751  std::unique_ptr<raw_fd_ostream> ThinLinkOS;
752 
753  switch (Action) {
754  case Backend_EmitNothing:
755  break;
756 
757  case Backend_EmitBC:
758  if (CodeGenOpts.EmitSummaryIndex) {
759  if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
760  std::error_code EC;
761  ThinLinkOS.reset(new llvm::raw_fd_ostream(
762  CodeGenOpts.ThinLinkBitcodeFile, EC,
763  llvm::sys::fs::F_None));
764  if (EC) {
765  Diags.Report(diag::err_fe_unable_to_open_output) << CodeGenOpts.ThinLinkBitcodeFile
766  << EC.message();
767  return;
768  }
769  }
770  PerModulePasses.add(
771  createWriteThinLTOBitcodePass(*OS, ThinLinkOS.get()));
772  }
773  else
774  PerModulePasses.add(
775  createBitcodeWriterPass(*OS, CodeGenOpts.EmitLLVMUseLists));
776  break;
777 
778  case Backend_EmitLL:
779  PerModulePasses.add(
780  createPrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
781  break;
782 
783  default:
784  if (!AddEmitPasses(CodeGenPasses, Action, *OS))
785  return;
786  }
787 
788  // Before executing passes, print the final values of the LLVM options.
789  cl::PrintOptionValues();
790 
791  // Run passes. For now we do all passes at once, but eventually we
792  // would like to have the option of streaming code generation.
793 
794  {
795  PrettyStackTraceString CrashInfo("Per-function optimization");
796 
797  PerFunctionPasses.doInitialization();
798  for (Function &F : *TheModule)
799  if (!F.isDeclaration())
800  PerFunctionPasses.run(F);
801  PerFunctionPasses.doFinalization();
802  }
803 
804  {
805  PrettyStackTraceString CrashInfo("Per-module optimization passes");
806  PerModulePasses.run(*TheModule);
807  }
808 
809  {
810  PrettyStackTraceString CrashInfo("Code generation");
811  CodeGenPasses.run(*TheModule);
812  }
813 }
814 
815 static PassBuilder::OptimizationLevel mapToLevel(const CodeGenOptions &Opts) {
816  switch (Opts.OptimizationLevel) {
817  default:
818  llvm_unreachable("Invalid optimization level!");
819 
820  case 1:
821  return PassBuilder::O1;
822 
823  case 2:
824  switch (Opts.OptimizeSize) {
825  default:
826  llvm_unreachable("Invalide optimization level for size!");
827 
828  case 0:
829  return PassBuilder::O2;
830 
831  case 1:
832  return PassBuilder::Os;
833 
834  case 2:
835  return PassBuilder::Oz;
836  }
837 
838  case 3:
839  return PassBuilder::O3;
840  }
841 }
842 
843 /// A clean version of `EmitAssembly` that uses the new pass manager.
844 ///
845 /// Not all features are currently supported in this system, but where
846 /// necessary it falls back to the legacy pass manager to at least provide
847 /// basic functionality.
848 ///
849 /// This API is planned to have its functionality finished and then to replace
850 /// `EmitAssembly` at some point in the future when the default switches.
851 void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
852  BackendAction Action, std::unique_ptr<raw_pwrite_stream> OS) {
853  TimeRegion Region(llvm::TimePassesIsEnabled ? &CodeGenerationTime : nullptr);
854  setCommandLineOpts(CodeGenOpts);
855 
856  // The new pass manager always makes a target machine available to passes
857  // during construction.
858  CreateTargetMachine(/*MustCreateTM*/ true);
859  if (!TM)
860  // This will already be diagnosed, just bail.
861  return;
862  TheModule->setDataLayout(TM->createDataLayout());
863 
864  Optional<PGOOptions> PGOOpt;
865 
866  if (CodeGenOpts.hasProfileIRInstr())
867  // -fprofile-generate.
868  PGOOpt = PGOOptions(CodeGenOpts.InstrProfileOutput.empty()
869  ? DefaultProfileGenName
870  : CodeGenOpts.InstrProfileOutput,
871  "", "", true, CodeGenOpts.DebugInfoForProfiling);
872  else if (CodeGenOpts.hasProfileIRUse())
873  // -fprofile-use.
874  PGOOpt = PGOOptions("", CodeGenOpts.ProfileInstrumentUsePath, "", false,
875  CodeGenOpts.DebugInfoForProfiling);
876  else if (!CodeGenOpts.SampleProfileFile.empty())
877  // -fprofile-sample-use
878  PGOOpt = PGOOptions("", "", CodeGenOpts.SampleProfileFile, false,
879  CodeGenOpts.DebugInfoForProfiling);
880  else if (CodeGenOpts.DebugInfoForProfiling)
881  // -fdebug-info-for-profiling
882  PGOOpt = PGOOptions("", "", "", false, true);
883 
884  PassBuilder PB(TM.get(), PGOOpt);
885 
886  LoopAnalysisManager LAM(CodeGenOpts.DebugPassManager);
887  FunctionAnalysisManager FAM(CodeGenOpts.DebugPassManager);
888  CGSCCAnalysisManager CGAM(CodeGenOpts.DebugPassManager);
889  ModuleAnalysisManager MAM(CodeGenOpts.DebugPassManager);
890 
891  // Register the AA manager first so that our version is the one used.
892  FAM.registerPass([&] { return PB.buildDefaultAAPipeline(); });
893 
894  // Register the target library analysis directly and give it a customized
895  // preset TLI.
896  Triple TargetTriple(TheModule->getTargetTriple());
897  std::unique_ptr<TargetLibraryInfoImpl> TLII(
898  createTLII(TargetTriple, CodeGenOpts));
899  FAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
900  MAM.registerPass([&] { return TargetLibraryAnalysis(*TLII); });
901 
902  // Register all the basic analyses with the managers.
903  PB.registerModuleAnalyses(MAM);
904  PB.registerCGSCCAnalyses(CGAM);
905  PB.registerFunctionAnalyses(FAM);
906  PB.registerLoopAnalyses(LAM);
907  PB.crossRegisterProxies(LAM, FAM, CGAM, MAM);
908 
909  ModulePassManager MPM(CodeGenOpts.DebugPassManager);
910 
911  if (!CodeGenOpts.DisableLLVMPasses) {
912  bool IsThinLTO = CodeGenOpts.EmitSummaryIndex;
913  bool IsLTO = CodeGenOpts.PrepareForLTO;
914 
915  if (CodeGenOpts.OptimizationLevel == 0) {
916  // Build a minimal pipeline based on the semantics required by Clang,
917  // which is just that always inlining occurs.
918  MPM.addPass(AlwaysInlinerPass());
919 
920  // At -O0 we directly run necessary sanitizer passes.
921  if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
922  MPM.addPass(createModuleToFunctionPassAdaptor(BoundsCheckingPass()));
923 
924  // Lastly, add a semantically necessary pass for ThinLTO.
925  if (IsThinLTO)
926  MPM.addPass(NameAnonGlobalPass());
927  } else {
928  // Map our optimization levels into one of the distinct levels used to
929  // configure the pipeline.
930  PassBuilder::OptimizationLevel Level = mapToLevel(CodeGenOpts);
931 
932  // Register callbacks to schedule sanitizer passes at the appropriate part of
933  // the pipeline.
934  if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
935  PB.registerScalarOptimizerLateEPCallback(
936  [](FunctionPassManager &FPM, PassBuilder::OptimizationLevel Level) {
937  FPM.addPass(BoundsCheckingPass());
938  });
939 
940  if (IsThinLTO) {
941  MPM = PB.buildThinLTOPreLinkDefaultPipeline(
942  Level, CodeGenOpts.DebugPassManager);
943  MPM.addPass(NameAnonGlobalPass());
944  } else if (IsLTO) {
945  MPM = PB.buildLTOPreLinkDefaultPipeline(Level,
946  CodeGenOpts.DebugPassManager);
947  } else {
948  MPM = PB.buildPerModuleDefaultPipeline(Level,
949  CodeGenOpts.DebugPassManager);
950  }
951  }
952  }
953 
954  // FIXME: We still use the legacy pass manager to do code generation. We
955  // create that pass manager here and use it as needed below.
956  legacy::PassManager CodeGenPasses;
957  bool NeedCodeGen = false;
958  Optional<raw_fd_ostream> ThinLinkOS;
959 
960  // Append any output we need to the pass manager.
961  switch (Action) {
962  case Backend_EmitNothing:
963  break;
964 
965  case Backend_EmitBC:
966  if (CodeGenOpts.EmitSummaryIndex) {
967  if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
968  std::error_code EC;
969  ThinLinkOS.emplace(CodeGenOpts.ThinLinkBitcodeFile, EC,
970  llvm::sys::fs::F_None);
971  if (EC) {
972  Diags.Report(diag::err_fe_unable_to_open_output)
973  << CodeGenOpts.ThinLinkBitcodeFile << EC.message();
974  return;
975  }
976  }
977  MPM.addPass(
978  ThinLTOBitcodeWriterPass(*OS, ThinLinkOS ? &*ThinLinkOS : nullptr));
979  } else {
980  MPM.addPass(BitcodeWriterPass(*OS, CodeGenOpts.EmitLLVMUseLists,
981  CodeGenOpts.EmitSummaryIndex,
982  CodeGenOpts.EmitSummaryIndex));
983  }
984  break;
985 
986  case Backend_EmitLL:
987  MPM.addPass(PrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
988  break;
989 
991  case Backend_EmitMCNull:
992  case Backend_EmitObj:
993  NeedCodeGen = true;
994  CodeGenPasses.add(
995  createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
996  if (!AddEmitPasses(CodeGenPasses, Action, *OS))
997  // FIXME: Should we handle this error differently?
998  return;
999  break;
1000  }
1001 
1002  // Before executing passes, print the final values of the LLVM options.
1003  cl::PrintOptionValues();
1004 
1005  // Now that we have all of the passes ready, run them.
1006  {
1007  PrettyStackTraceString CrashInfo("Optimizer");
1008  MPM.run(*TheModule, MAM);
1009  }
1010 
1011  // Now if needed, run the legacy PM for codegen.
1012  if (NeedCodeGen) {
1013  PrettyStackTraceString CrashInfo("Code generation");
1014  CodeGenPasses.run(*TheModule);
1015  }
1016 }
1017 
1018 Expected<BitcodeModule> clang::FindThinLTOModule(MemoryBufferRef MBRef) {
1019  Expected<std::vector<BitcodeModule>> BMsOrErr = getBitcodeModuleList(MBRef);
1020  if (!BMsOrErr)
1021  return BMsOrErr.takeError();
1022 
1023  // The bitcode file may contain multiple modules, we want the one that is
1024  // marked as being the ThinLTO module.
1025  for (BitcodeModule &BM : *BMsOrErr) {
1026  Expected<BitcodeLTOInfo> LTOInfo = BM.getLTOInfo();
1027  if (LTOInfo && LTOInfo->IsThinLTO)
1028  return BM;
1029  }
1030 
1031  return make_error<StringError>("Could not find module summary",
1032  inconvertibleErrorCode());
1033 }
1034 
1035 static void runThinLTOBackend(ModuleSummaryIndex *CombinedIndex, Module *M,
1036  const HeaderSearchOptions &HeaderOpts,
1037  const CodeGenOptions &CGOpts,
1038  const clang::TargetOptions &TOpts,
1039  const LangOptions &LOpts,
1040  std::unique_ptr<raw_pwrite_stream> OS,
1041  std::string SampleProfile,
1042  BackendAction Action) {
1043  StringMap<DenseMap<GlobalValue::GUID, GlobalValueSummary *>>
1044  ModuleToDefinedGVSummaries;
1045  CombinedIndex->collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
1046 
1047  setCommandLineOpts(CGOpts);
1048 
1049  // We can simply import the values mentioned in the combined index, since
1050  // we should only invoke this using the individual indexes written out
1051  // via a WriteIndexesThinBackend.
1052  FunctionImporter::ImportMapTy ImportList;
1053  for (auto &GlobalList : *CombinedIndex) {
1054  // Ignore entries for undefined references.
1055  if (GlobalList.second.SummaryList.empty())
1056  continue;
1057 
1058  auto GUID = GlobalList.first;
1059  assert(GlobalList.second.SummaryList.size() == 1 &&
1060  "Expected individual combined index to have one summary per GUID");
1061  auto &Summary = GlobalList.second.SummaryList[0];
1062  // Skip the summaries for the importing module. These are included to
1063  // e.g. record required linkage changes.
1064  if (Summary->modulePath() == M->getModuleIdentifier())
1065  continue;
1066  // Doesn't matter what value we plug in to the map, just needs an entry
1067  // to provoke importing by thinBackend.
1068  ImportList[Summary->modulePath()][GUID] = 1;
1069  }
1070 
1071  std::vector<std::unique_ptr<llvm::MemoryBuffer>> OwnedImports;
1072  MapVector<llvm::StringRef, llvm::BitcodeModule> ModuleMap;
1073 
1074  for (auto &I : ImportList) {
1075  ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> MBOrErr =
1076  llvm::MemoryBuffer::getFile(I.first());
1077  if (!MBOrErr) {
1078  errs() << "Error loading imported file '" << I.first()
1079  << "': " << MBOrErr.getError().message() << "\n";
1080  return;
1081  }
1082 
1083  Expected<BitcodeModule> BMOrErr = FindThinLTOModule(**MBOrErr);
1084  if (!BMOrErr) {
1085  handleAllErrors(BMOrErr.takeError(), [&](ErrorInfoBase &EIB) {
1086  errs() << "Error loading imported file '" << I.first()
1087  << "': " << EIB.message() << '\n';
1088  });
1089  return;
1090  }
1091  ModuleMap.insert({I.first(), *BMOrErr});
1092 
1093  OwnedImports.push_back(std::move(*MBOrErr));
1094  }
1095  auto AddStream = [&](size_t Task) {
1096  return llvm::make_unique<lto::NativeObjectStream>(std::move(OS));
1097  };
1098  lto::Config Conf;
1099  Conf.CPU = TOpts.CPU;
1100  Conf.CodeModel = getCodeModel(CGOpts);
1101  Conf.MAttrs = TOpts.Features;
1102  Conf.RelocModel = getRelocModel(CGOpts);
1103  Conf.CGOptLevel = getCGOptLevel(CGOpts);
1104  initTargetOptions(Conf.Options, CGOpts, TOpts, LOpts, HeaderOpts);
1105  Conf.SampleProfile = std::move(SampleProfile);
1106  Conf.UseNewPM = CGOpts.ExperimentalNewPassManager;
1107  Conf.DebugPassManager = CGOpts.DebugPassManager;
1108  switch (Action) {
1109  case Backend_EmitNothing:
1110  Conf.PreCodeGenModuleHook = [](size_t Task, const Module &Mod) {
1111  return false;
1112  };
1113  break;
1114  case Backend_EmitLL:
1115  Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1116  M->print(*OS, nullptr, CGOpts.EmitLLVMUseLists);
1117  return false;
1118  };
1119  break;
1120  case Backend_EmitBC:
1121  Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1122  WriteBitcodeToFile(M, *OS, CGOpts.EmitLLVMUseLists);
1123  return false;
1124  };
1125  break;
1126  default:
1127  Conf.CGFileType = getCodeGenFileType(Action);
1128  break;
1129  }
1130  if (Error E = thinBackend(
1131  Conf, 0, AddStream, *M, *CombinedIndex, ImportList,
1132  ModuleToDefinedGVSummaries[M->getModuleIdentifier()], ModuleMap)) {
1133  handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1134  errs() << "Error running ThinLTO backend: " << EIB.message() << '\n';
1135  });
1136  }
1137 }
1138 
1140  const HeaderSearchOptions &HeaderOpts,
1141  const CodeGenOptions &CGOpts,
1142  const clang::TargetOptions &TOpts,
1143  const LangOptions &LOpts,
1144  const llvm::DataLayout &TDesc, Module *M,
1145  BackendAction Action,
1146  std::unique_ptr<raw_pwrite_stream> OS) {
1147  if (!CGOpts.ThinLTOIndexFile.empty()) {
1148  // If we are performing a ThinLTO importing compile, load the function index
1149  // into memory and pass it into runThinLTOBackend, which will run the
1150  // function importer and invoke LTO passes.
1152  llvm::getModuleSummaryIndexForFile(CGOpts.ThinLTOIndexFile,
1153  /*IgnoreEmptyThinLTOIndexFile*/true);
1154  if (!IndexOrErr) {
1155  logAllUnhandledErrors(IndexOrErr.takeError(), errs(),
1156  "Error loading index file '" +
1157  CGOpts.ThinLTOIndexFile + "': ");
1158  return;
1159  }
1160  std::unique_ptr<ModuleSummaryIndex> CombinedIndex = std::move(*IndexOrErr);
1161  // A null CombinedIndex means we should skip ThinLTO compilation
1162  // (LLVM will optionally ignore empty index files, returning null instead
1163  // of an error).
1164  bool DoThinLTOBackend = CombinedIndex != nullptr;
1165  if (DoThinLTOBackend) {
1166  runThinLTOBackend(CombinedIndex.get(), M, HeaderOpts, CGOpts, TOpts,
1167  LOpts, std::move(OS), CGOpts.SampleProfileFile, Action);
1168  return;
1169  }
1170  }
1171 
1172  EmitAssemblyHelper AsmHelper(Diags, HeaderOpts, CGOpts, TOpts, LOpts, M);
1173 
1174  if (CGOpts.ExperimentalNewPassManager)
1175  AsmHelper.EmitAssemblyWithNewPassManager(Action, std::move(OS));
1176  else
1177  AsmHelper.EmitAssembly(Action, std::move(OS));
1178 
1179  // Verify clang's TargetInfo DataLayout against the LLVM TargetMachine's
1180  // DataLayout.
1181  if (AsmHelper.TM) {
1182  std::string DLDesc = M->getDataLayout().getStringRepresentation();
1183  if (DLDesc != TDesc.getStringRepresentation()) {
1184  unsigned DiagID = Diags.getCustomDiagID(
1185  DiagnosticsEngine::Error, "backend data layout '%0' does not match "
1186  "expected target description '%1'");
1187  Diags.Report(DiagID) << DLDesc << TDesc.getStringRepresentation();
1188  }
1189  }
1190 }
1191 
1192 static const char* getSectionNameForBitcode(const Triple &T) {
1193  switch (T.getObjectFormat()) {
1194  case Triple::MachO:
1195  return "__LLVM,__bitcode";
1196  case Triple::COFF:
1197  case Triple::ELF:
1198  case Triple::Wasm:
1199  case Triple::UnknownObjectFormat:
1200  return ".llvmbc";
1201  }
1202  llvm_unreachable("Unimplemented ObjectFormatType");
1203 }
1204 
1205 static const char* getSectionNameForCommandline(const Triple &T) {
1206  switch (T.getObjectFormat()) {
1207  case Triple::MachO:
1208  return "__LLVM,__cmdline";
1209  case Triple::COFF:
1210  case Triple::ELF:
1211  case Triple::Wasm:
1212  case Triple::UnknownObjectFormat:
1213  return ".llvmcmd";
1214  }
1215  llvm_unreachable("Unimplemented ObjectFormatType");
1216 }
1217 
1218 // With -fembed-bitcode, save a copy of the llvm IR as data in the
1219 // __LLVM,__bitcode section.
1220 void clang::EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts,
1221  llvm::MemoryBufferRef Buf) {
1222  if (CGOpts.getEmbedBitcode() == CodeGenOptions::Embed_Off)
1223  return;
1224 
1225  // Save llvm.compiler.used and remote it.
1226  SmallVector<Constant*, 2> UsedArray;
1227  SmallSet<GlobalValue*, 4> UsedGlobals;
1228  Type *UsedElementType = Type::getInt8Ty(M->getContext())->getPointerTo(0);
1229  GlobalVariable *Used = collectUsedGlobalVariables(*M, UsedGlobals, true);
1230  for (auto *GV : UsedGlobals) {
1231  if (GV->getName() != "llvm.embedded.module" &&
1232  GV->getName() != "llvm.cmdline")
1233  UsedArray.push_back(
1234  ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
1235  }
1236  if (Used)
1237  Used->eraseFromParent();
1238 
1239  // Embed the bitcode for the llvm module.
1240  std::string Data;
1241  ArrayRef<uint8_t> ModuleData;
1242  Triple T(M->getTargetTriple());
1243  // Create a constant that contains the bitcode.
1244  // In case of embedding a marker, ignore the input Buf and use the empty
1245  // ArrayRef. It is also legal to create a bitcode marker even Buf is empty.
1246  if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Marker) {
1247  if (!isBitcode((const unsigned char *)Buf.getBufferStart(),
1248  (const unsigned char *)Buf.getBufferEnd())) {
1249  // If the input is LLVM Assembly, bitcode is produced by serializing
1250  // the module. Use-lists order need to be perserved in this case.
1251  llvm::raw_string_ostream OS(Data);
1252  llvm::WriteBitcodeToFile(M, OS, /* ShouldPreserveUseListOrder */ true);
1253  ModuleData =
1254  ArrayRef<uint8_t>((const uint8_t *)OS.str().data(), OS.str().size());
1255  } else
1256  // If the input is LLVM bitcode, write the input byte stream directly.
1257  ModuleData = ArrayRef<uint8_t>((const uint8_t *)Buf.getBufferStart(),
1258  Buf.getBufferSize());
1259  }
1260  llvm::Constant *ModuleConstant =
1261  llvm::ConstantDataArray::get(M->getContext(), ModuleData);
1262  llvm::GlobalVariable *GV = new llvm::GlobalVariable(
1263  *M, ModuleConstant->getType(), true, llvm::GlobalValue::PrivateLinkage,
1264  ModuleConstant);
1265  GV->setSection(getSectionNameForBitcode(T));
1266  UsedArray.push_back(
1267  ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
1268  if (llvm::GlobalVariable *Old =
1269  M->getGlobalVariable("llvm.embedded.module", true)) {
1270  assert(Old->hasOneUse() &&
1271  "llvm.embedded.module can only be used once in llvm.compiler.used");
1272  GV->takeName(Old);
1273  Old->eraseFromParent();
1274  } else {
1275  GV->setName("llvm.embedded.module");
1276  }
1277 
1278  // Skip if only bitcode needs to be embedded.
1279  if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Bitcode) {
1280  // Embed command-line options.
1281  ArrayRef<uint8_t> CmdData(const_cast<uint8_t *>(CGOpts.CmdArgs.data()),
1282  CGOpts.CmdArgs.size());
1283  llvm::Constant *CmdConstant =
1284  llvm::ConstantDataArray::get(M->getContext(), CmdData);
1285  GV = new llvm::GlobalVariable(*M, CmdConstant->getType(), true,
1286  llvm::GlobalValue::PrivateLinkage,
1287  CmdConstant);
1288  GV->setSection(getSectionNameForCommandline(T));
1289  UsedArray.push_back(
1290  ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
1291  if (llvm::GlobalVariable *Old =
1292  M->getGlobalVariable("llvm.cmdline", true)) {
1293  assert(Old->hasOneUse() &&
1294  "llvm.cmdline can only be used once in llvm.compiler.used");
1295  GV->takeName(Old);
1296  Old->eraseFromParent();
1297  } else {
1298  GV->setName("llvm.cmdline");
1299  }
1300  }
1301 
1302  if (UsedArray.empty())
1303  return;
1304 
1305  // Recreate llvm.compiler.used.
1306  ArrayType *ATy = ArrayType::get(UsedElementType, UsedArray.size());
1307  auto *NewUsed = new GlobalVariable(
1308  *M, ATy, false, llvm::GlobalValue::AppendingLinkage,
1309  llvm::ConstantArray::get(ATy, UsedArray), "llvm.compiler.used");
1310  NewUsed->setSection("llvm.metadata");
1311 }
std::string ProfileInstrumentUsePath
Name of the profile file to use as input for -fprofile-instr-use.
static void runThinLTOBackend(ModuleSummaryIndex *CombinedIndex, Module *M, const HeaderSearchOptions &HeaderOpts, const CodeGenOptions &CGOpts, const clang::TargetOptions &TOpts, const LangOptions &LOpts, std::unique_ptr< raw_pwrite_stream > OS, std::string SampleProfile, BackendAction Action)
Paths for &#39;#include <>&#39; added by &#39;-I&#39;.
static void addObjCARCExpandPass(const PassManagerBuilder &Builder, PassManagerBase &PM)
if(T->getSizeExpr()) TRY_TO(TraverseStmt(T -> getSizeExpr()))
Emit human-readable LLVM assembly.
Definition: BackendUtil.h:34
DominatorTree GraphTraits specialization so the DominatorTree can be iterable by generic graph iterat...
Definition: Dominators.h:26
Run CodeGen, but don&#39;t emit anything.
Definition: BackendUtil.h:36
SanitizerSet Sanitize
Set of enabled sanitizers.
Definition: LangOptions.h:101
The base class of the type hierarchy.
Definition: Type.h:1353
std::string SampleProfileFile
Name of the profile file to use with -fprofile-sample-use.
DiagnosticBuilder Report(SourceLocation Loc, unsigned DiagID)
Issue the message to the client.
Definition: Diagnostic.h:1207
Represents an array type, per C99 6.7.5.2 - Array Declarators.
Definition: Type.h:2560
static void addAddressSanitizerPasses(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
std::vector< std::string > RewriteMapFiles
Set of files defining the rules for the symbol rewriting.
Don&#39;t emit anything (benchmarking mode)
Definition: BackendUtil.h:35
Options for controlling the target.
Definition: TargetOptions.h:26
std::string SplitDwarfFile
The name for the split debug info file that we&#39;ll break out.
std::string DebugPass
Enable additional debugging information.
SanitizerSet SanitizeRecover
Set of sanitizer checks that are non-fatal (i.e.
bool hasOneOf(SanitizerMask K) const
Check if one or more sanitizers are enabled.
Definition: Sanitizers.h:56
Emit LLVM bitcode files.
Definition: BackendUtil.h:33
std::vector< Entry > UserEntries
User specified include entries.
std::vector< uint8_t > CmdArgs
List of backend command-line options for -fembed-bitcode.
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:48
std::string CodeModel
The code model to use (-mcmodel).
Describes a module or submodule.
Definition: Module.h:65
BackendAction
Definition: BackendUtil.h:31
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:147
static void addThreadSanitizerPass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
Defines the Diagnostic-related interfaces.
static CodeGenOpt::Level getCGOptLevel(const CodeGenOptions &CodeGenOpts)
static void setCommandLineOpts(const CodeGenOptions &CodeGenOpts)
static void addSanitizerCoveragePass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
std::string FloatABI
The ABI to use for passing floating point arguments.
std::string ThreadModel
The thread model to use.
char CoverageVersion[4]
The version string to put into coverage files.
std::string LimitFloatPrecision
The float precision limit to use, if non-empty.
Defines the clang::LangOptions interface.
const FunctionProtoType * T
static void addHWAddressSanitizerPasses(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
static void addObjCARCAPElimPass(const PassManagerBuilder &Builder, PassManagerBase &PM)
std::string RelocationModel
The name of the relocation model to use.
void print(raw_ostream &OS, unsigned Indent=0) const
Print the module map for this module to the given stream.
Definition: Module.cpp:360
static TargetLibraryInfoImpl * createTLII(llvm::Triple &TargetTriple, const CodeGenOptions &CodeGenOpts)
Emit native object files.
Definition: BackendUtil.h:37
Emit native assembly files.
Definition: BackendUtil.h:32
std::string CPU
If given, the name of the target CPU to generate code for.
Definition: TargetOptions.h:36
static llvm::Reloc::Model getRelocModel(const CodeGenOptions &CodeGenOpts)
std::string ABI
If given, the name of the target ABI to use.
Definition: TargetOptions.h:42
static void addKernelAddressSanitizerPasses(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
static void addSymbolRewriterPass(const CodeGenOptions &Opts, legacy::PassManager *MPM)
static void addDataFlowSanitizerPass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
Defines the clang::TargetOptions class.
std::vector< std::string > Features
The list of target specific features to enable or disable – this should be a list of strings startin...
Definition: TargetOptions.h:55
static void initTargetOptions(llvm::TargetOptions &Options, const CodeGenOptions &CodeGenOpts, const clang::TargetOptions &TargetOpts, const LangOptions &LangOpts, const HeaderSearchOptions &HSOpts)
static bool asanUseGlobalsGC(const Triple &T, const CodeGenOptions &CGOpts)
unsigned getCustomDiagID(Level L, const char(&FormatString)[N])
Return an ID for a diagnostic with the specified format string and level.
Definition: Diagnostic.h:691
llvm::EABI EABIVersion
The EABI version to use.
Definition: TargetOptions.h:45
&#39;#include ""&#39; paths, added by &#39;gcc -iquote&#39;.
std::string ThinLTOIndexFile
Name of the function summary index file to use for ThinLTO function importing.
Like Angled, but marks system directories.
static TargetMachine::CodeGenFileType getCodeGenFileType(BackendAction Action)
void EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts, llvm::MemoryBufferRef Buf)
Dataflow Directional Tag Classes.
bool hasProfileIRUse() const
Check if IR level profile use is on.
void EmitBackendOutput(DiagnosticsEngine &Diags, const HeaderSearchOptions &, const CodeGenOptions &CGOpts, const TargetOptions &TOpts, const LangOptions &LOpts, const llvm::DataLayout &TDesc, llvm::Module *M, BackendAction Action, std::unique_ptr< raw_pwrite_stream > OS)
bool hasProfileClangInstr() const
Check if Clang profile instrumenation is on.
llvm::Expected< llvm::BitcodeModule > FindThinLTOModule(llvm::MemoryBufferRef MBRef)
static const char * getSectionNameForBitcode(const Triple &T)
static const char * getSectionNameForCommandline(const Triple &T)
void BuryPointer(const void *Ptr)
static void addBoundsCheckingPass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
static void addEfficiencySanitizerPass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
static Optional< llvm::CodeModel::Model > getCodeModel(const CodeGenOptions &CodeGenOpts)
CodeGenOptions - Track various options which control how the code is optimized and passed to the back...
static void addObjCARCOptPass(const PassManagerBuilder &Builder, PassManagerBase &PM)
bool hasProfileIRInstr() const
Check if IR level profile instrumentation is on.
const std::vector< std::string > & getNoBuiltinFuncs() const
bool has(SanitizerMask K) const
Check if a certain (single) sanitizer is enabled.
Definition: Sanitizers.h:50
StringLiteral - This represents a string literal expression, e.g.
Definition: Expr.h:1509
static void addAddDiscriminatorsPass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
HeaderSearchOptions - Helper class for storing options related to the initialization of the HeaderSea...
std::string InstrProfileOutput
Name of the profile file to use as output for -fprofile-instr-generate and -fprofile-generate.
std::string ThinLinkBitcodeFile
Name of a file that can optionally be written with minimized bitcode to be used as input for the Thin...
std::vector< std::string > SanitizerBlacklistFiles
Paths to blacklist files specifying which objects (files, functions, variables) should not be instrum...
Definition: LangOptions.h:105
std::vector< std::string > BackendOptions
A list of command-line options to forward to the LLVM backend.
std::string Sysroot
If non-empty, the directory to use as a "virtual system root" for include paths.
static void addMemorySanitizerPass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
static PassBuilder::OptimizationLevel mapToLevel(const CodeGenOptions &Opts)