clang  5.0.0
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/Target/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/ObjCARC.h"
55 #include "llvm/Transforms/Scalar.h"
56 #include "llvm/Transforms/Scalar/GVN.h"
57 #include "llvm/Transforms/Utils/NameAnonGlobals.h"
58 #include "llvm/Transforms/Utils/SymbolRewriter.h"
59 #include <memory>
60 using namespace clang;
61 using namespace llvm;
62 
63 namespace {
64 
65 // Default filename used for profile generation.
66 static constexpr StringLiteral DefaultProfileGenName = "default_%m.profraw";
67 
68 class EmitAssemblyHelper {
69  DiagnosticsEngine &Diags;
70  const HeaderSearchOptions &HSOpts;
71  const CodeGenOptions &CodeGenOpts;
72  const clang::TargetOptions &TargetOpts;
73  const LangOptions &LangOpts;
74  Module *TheModule;
75 
76  Timer CodeGenerationTime;
77 
78  std::unique_ptr<raw_pwrite_stream> OS;
79 
80  TargetIRAnalysis getTargetIRAnalysis() const {
81  if (TM)
82  return TM->getTargetIRAnalysis();
83 
84  return TargetIRAnalysis();
85  }
86 
87  void CreatePasses(legacy::PassManager &MPM, legacy::FunctionPassManager &FPM);
88 
89  /// Generates the TargetMachine.
90  /// Leaves TM unchanged if it is unable to create the target machine.
91  /// Some of our clang tests specify triples which are not built
92  /// into clang. This is okay because these tests check the generated
93  /// IR, and they require DataLayout which depends on the triple.
94  /// In this case, we allow this method to fail and not report an error.
95  /// When MustCreateTM is used, we print an error if we are unable to load
96  /// the requested target.
97  void CreateTargetMachine(bool MustCreateTM);
98 
99  /// Add passes necessary to emit assembly or LLVM IR.
100  ///
101  /// \return True on success.
102  bool AddEmitPasses(legacy::PassManager &CodeGenPasses, BackendAction Action,
103  raw_pwrite_stream &OS);
104 
105 public:
106  EmitAssemblyHelper(DiagnosticsEngine &_Diags,
107  const HeaderSearchOptions &HeaderSearchOpts,
108  const CodeGenOptions &CGOpts,
109  const clang::TargetOptions &TOpts,
110  const LangOptions &LOpts, Module *M)
111  : Diags(_Diags), HSOpts(HeaderSearchOpts), CodeGenOpts(CGOpts),
112  TargetOpts(TOpts), LangOpts(LOpts), TheModule(M),
113  CodeGenerationTime("codegen", "Code Generation Time") {}
114 
115  ~EmitAssemblyHelper() {
116  if (CodeGenOpts.DisableFree)
117  BuryPointer(std::move(TM));
118  }
119 
120  std::unique_ptr<TargetMachine> TM;
121 
123  std::unique_ptr<raw_pwrite_stream> OS);
124 
125  void EmitAssemblyWithNewPassManager(BackendAction Action,
126  std::unique_ptr<raw_pwrite_stream> OS);
127 };
128 
129 // We need this wrapper to access LangOpts and CGOpts from extension functions
130 // that we add to the PassManagerBuilder.
131 class PassManagerBuilderWrapper : public PassManagerBuilder {
132 public:
133  PassManagerBuilderWrapper(const Triple &TargetTriple,
134  const CodeGenOptions &CGOpts,
135  const LangOptions &LangOpts)
136  : PassManagerBuilder(), TargetTriple(TargetTriple), CGOpts(CGOpts),
137  LangOpts(LangOpts) {}
138  const Triple &getTargetTriple() const { return TargetTriple; }
139  const CodeGenOptions &getCGOpts() const { return CGOpts; }
140  const LangOptions &getLangOpts() const { return LangOpts; }
141 
142 private:
143  const Triple &TargetTriple;
144  const CodeGenOptions &CGOpts;
145  const LangOptions &LangOpts;
146 };
147 }
148 
149 static void addObjCARCAPElimPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
150  if (Builder.OptLevel > 0)
151  PM.add(createObjCARCAPElimPass());
152 }
153 
154 static void addObjCARCExpandPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
155  if (Builder.OptLevel > 0)
156  PM.add(createObjCARCExpandPass());
157 }
158 
159 static void addObjCARCOptPass(const PassManagerBuilder &Builder, PassManagerBase &PM) {
160  if (Builder.OptLevel > 0)
161  PM.add(createObjCARCOptPass());
162 }
163 
164 static void addAddDiscriminatorsPass(const PassManagerBuilder &Builder,
165  legacy::PassManagerBase &PM) {
166  PM.add(createAddDiscriminatorsPass());
167 }
168 
169 static void addBoundsCheckingPass(const PassManagerBuilder &Builder,
170  legacy::PassManagerBase &PM) {
171  PM.add(createBoundsCheckingPass());
172 }
173 
174 static void addSanitizerCoveragePass(const PassManagerBuilder &Builder,
175  legacy::PassManagerBase &PM) {
176  const PassManagerBuilderWrapper &BuilderWrapper =
177  static_cast<const PassManagerBuilderWrapper&>(Builder);
178  const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
179  SanitizerCoverageOptions Opts;
180  Opts.CoverageType =
181  static_cast<SanitizerCoverageOptions::Type>(CGOpts.SanitizeCoverageType);
182  Opts.IndirectCalls = CGOpts.SanitizeCoverageIndirectCalls;
183  Opts.TraceBB = CGOpts.SanitizeCoverageTraceBB;
184  Opts.TraceCmp = CGOpts.SanitizeCoverageTraceCmp;
185  Opts.TraceDiv = CGOpts.SanitizeCoverageTraceDiv;
186  Opts.TraceGep = CGOpts.SanitizeCoverageTraceGep;
187  Opts.Use8bitCounters = CGOpts.SanitizeCoverage8bitCounters;
188  Opts.TracePC = CGOpts.SanitizeCoverageTracePC;
189  Opts.TracePCGuard = CGOpts.SanitizeCoverageTracePCGuard;
190  Opts.NoPrune = CGOpts.SanitizeCoverageNoPrune;
191  Opts.Inline8bitCounters = CGOpts.SanitizeCoverageInline8bitCounters;
192  PM.add(createSanitizerCoverageModulePass(Opts));
193 }
194 
195 // Check if ASan should use GC-friendly instrumentation for globals.
196 // First of all, there is no point if -fdata-sections is off (expect for MachO,
197 // where this is not a factor). Also, on ELF this feature requires an assembler
198 // extension that only works with -integrated-as at the moment.
199 static bool asanUseGlobalsGC(const Triple &T, const CodeGenOptions &CGOpts) {
200  if (!CGOpts.SanitizeAddressGlobalsDeadStripping)
201  return false;
202  switch (T.getObjectFormat()) {
203  case Triple::MachO:
204  case Triple::COFF:
205  return true;
206  case Triple::ELF:
207  return CGOpts.DataSections && !CGOpts.DisableIntegratedAS;
208  default:
209  return false;
210  }
211 }
212 
213 static void addAddressSanitizerPasses(const PassManagerBuilder &Builder,
214  legacy::PassManagerBase &PM) {
215  const PassManagerBuilderWrapper &BuilderWrapper =
216  static_cast<const PassManagerBuilderWrapper&>(Builder);
217  const Triple &T = BuilderWrapper.getTargetTriple();
218  const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
219  bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Address);
220  bool UseAfterScope = CGOpts.SanitizeAddressUseAfterScope;
221  bool UseGlobalsGC = asanUseGlobalsGC(T, CGOpts);
222  PM.add(createAddressSanitizerFunctionPass(/*CompileKernel*/ false, Recover,
223  UseAfterScope));
224  PM.add(createAddressSanitizerModulePass(/*CompileKernel*/ false, Recover,
225  UseGlobalsGC));
226 }
227 
228 static void addKernelAddressSanitizerPasses(const PassManagerBuilder &Builder,
229  legacy::PassManagerBase &PM) {
230  PM.add(createAddressSanitizerFunctionPass(
231  /*CompileKernel*/ true,
232  /*Recover*/ true, /*UseAfterScope*/ false));
233  PM.add(createAddressSanitizerModulePass(/*CompileKernel*/true,
234  /*Recover*/true));
235 }
236 
237 static void addMemorySanitizerPass(const PassManagerBuilder &Builder,
238  legacy::PassManagerBase &PM) {
239  const PassManagerBuilderWrapper &BuilderWrapper =
240  static_cast<const PassManagerBuilderWrapper&>(Builder);
241  const CodeGenOptions &CGOpts = BuilderWrapper.getCGOpts();
242  int TrackOrigins = CGOpts.SanitizeMemoryTrackOrigins;
243  bool Recover = CGOpts.SanitizeRecover.has(SanitizerKind::Memory);
244  PM.add(createMemorySanitizerPass(TrackOrigins, Recover));
245 
246  // MemorySanitizer inserts complex instrumentation that mostly follows
247  // the logic of the original code, but operates on "shadow" values.
248  // It can benefit from re-running some general purpose optimization passes.
249  if (Builder.OptLevel > 0) {
250  PM.add(createEarlyCSEPass());
251  PM.add(createReassociatePass());
252  PM.add(createLICMPass());
253  PM.add(createGVNPass());
254  PM.add(createInstructionCombiningPass());
255  PM.add(createDeadStoreEliminationPass());
256  }
257 }
258 
259 static void addThreadSanitizerPass(const PassManagerBuilder &Builder,
260  legacy::PassManagerBase &PM) {
261  PM.add(createThreadSanitizerPass());
262 }
263 
264 static void addDataFlowSanitizerPass(const PassManagerBuilder &Builder,
265  legacy::PassManagerBase &PM) {
266  const PassManagerBuilderWrapper &BuilderWrapper =
267  static_cast<const PassManagerBuilderWrapper&>(Builder);
268  const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
269  PM.add(createDataFlowSanitizerPass(LangOpts.SanitizerBlacklistFiles));
270 }
271 
272 static void addEfficiencySanitizerPass(const PassManagerBuilder &Builder,
273  legacy::PassManagerBase &PM) {
274  const PassManagerBuilderWrapper &BuilderWrapper =
275  static_cast<const PassManagerBuilderWrapper&>(Builder);
276  const LangOptions &LangOpts = BuilderWrapper.getLangOpts();
277  EfficiencySanitizerOptions Opts;
278  if (LangOpts.Sanitize.has(SanitizerKind::EfficiencyCacheFrag))
279  Opts.ToolType = EfficiencySanitizerOptions::ESAN_CacheFrag;
280  else if (LangOpts.Sanitize.has(SanitizerKind::EfficiencyWorkingSet))
281  Opts.ToolType = EfficiencySanitizerOptions::ESAN_WorkingSet;
282  PM.add(createEfficiencySanitizerPass(Opts));
283 }
284 
285 static TargetLibraryInfoImpl *createTLII(llvm::Triple &TargetTriple,
286  const CodeGenOptions &CodeGenOpts) {
287  TargetLibraryInfoImpl *TLII = new TargetLibraryInfoImpl(TargetTriple);
288  if (!CodeGenOpts.SimplifyLibCalls)
289  TLII->disableAllFunctions();
290  else {
291  // Disable individual libc/libm calls in TargetLibraryInfo.
292  LibFunc F;
293  for (auto &FuncName : CodeGenOpts.getNoBuiltinFuncs())
294  if (TLII->getLibFunc(FuncName, F))
295  TLII->setUnavailable(F);
296  }
297 
298  switch (CodeGenOpts.getVecLib()) {
300  TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::Accelerate);
301  break;
303  TLII->addVectorizableFunctionsFromVecLib(TargetLibraryInfoImpl::SVML);
304  break;
305  default:
306  break;
307  }
308  return TLII;
309 }
310 
311 static void addSymbolRewriterPass(const CodeGenOptions &Opts,
312  legacy::PassManager *MPM) {
313  llvm::SymbolRewriter::RewriteDescriptorList DL;
314 
315  llvm::SymbolRewriter::RewriteMapParser MapParser;
316  for (const auto &MapFile : Opts.RewriteMapFiles)
317  MapParser.parse(MapFile, &DL);
318 
319  MPM->add(createRewriteSymbolsPass(DL));
320 }
321 
322 static CodeGenOpt::Level getCGOptLevel(const CodeGenOptions &CodeGenOpts) {
323  switch (CodeGenOpts.OptimizationLevel) {
324  default:
325  llvm_unreachable("Invalid optimization level!");
326  case 0:
327  return CodeGenOpt::None;
328  case 1:
329  return CodeGenOpt::Less;
330  case 2:
331  return CodeGenOpt::Default; // O2/Os/Oz
332  case 3:
333  return CodeGenOpt::Aggressive;
334  }
335 }
336 
337 static llvm::CodeModel::Model getCodeModel(const CodeGenOptions &CodeGenOpts) {
338  unsigned CodeModel =
339  llvm::StringSwitch<unsigned>(CodeGenOpts.CodeModel)
340  .Case("small", llvm::CodeModel::Small)
341  .Case("kernel", llvm::CodeModel::Kernel)
342  .Case("medium", llvm::CodeModel::Medium)
343  .Case("large", llvm::CodeModel::Large)
344  .Case("default", llvm::CodeModel::Default)
345  .Default(~0u);
346  assert(CodeModel != ~0u && "invalid code model!");
347  return static_cast<llvm::CodeModel::Model>(CodeModel);
348 }
349 
350 static llvm::Reloc::Model getRelocModel(const CodeGenOptions &CodeGenOpts) {
351  // Keep this synced with the equivalent code in
352  // lib/Frontend/CompilerInvocation.cpp
354  RM = llvm::StringSwitch<llvm::Reloc::Model>(CodeGenOpts.RelocationModel)
355  .Case("static", llvm::Reloc::Static)
356  .Case("pic", llvm::Reloc::PIC_)
357  .Case("ropi", llvm::Reloc::ROPI)
358  .Case("rwpi", llvm::Reloc::RWPI)
359  .Case("ropi-rwpi", llvm::Reloc::ROPI_RWPI)
360  .Case("dynamic-no-pic", llvm::Reloc::DynamicNoPIC);
361  assert(RM.hasValue() && "invalid PIC model!");
362  return *RM;
363 }
364 
365 static TargetMachine::CodeGenFileType getCodeGenFileType(BackendAction Action) {
366  if (Action == Backend_EmitObj)
367  return TargetMachine::CGFT_ObjectFile;
368  else if (Action == Backend_EmitMCNull)
369  return TargetMachine::CGFT_Null;
370  else {
371  assert(Action == Backend_EmitAssembly && "Invalid action!");
372  return TargetMachine::CGFT_AssemblyFile;
373  }
374 }
375 
376 static void initTargetOptions(llvm::TargetOptions &Options,
377  const CodeGenOptions &CodeGenOpts,
378  const clang::TargetOptions &TargetOpts,
379  const LangOptions &LangOpts,
380  const HeaderSearchOptions &HSOpts) {
381  Options.ThreadModel =
382  llvm::StringSwitch<llvm::ThreadModel::Model>(CodeGenOpts.ThreadModel)
383  .Case("posix", llvm::ThreadModel::POSIX)
384  .Case("single", llvm::ThreadModel::Single);
385 
386  // Set float ABI type.
387  assert((CodeGenOpts.FloatABI == "soft" || CodeGenOpts.FloatABI == "softfp" ||
388  CodeGenOpts.FloatABI == "hard" || CodeGenOpts.FloatABI.empty()) &&
389  "Invalid Floating Point ABI!");
390  Options.FloatABIType =
391  llvm::StringSwitch<llvm::FloatABI::ABIType>(CodeGenOpts.FloatABI)
392  .Case("soft", llvm::FloatABI::Soft)
393  .Case("softfp", llvm::FloatABI::Soft)
394  .Case("hard", llvm::FloatABI::Hard)
395  .Default(llvm::FloatABI::Default);
396 
397  // Set FP fusion mode.
398  switch (LangOpts.getDefaultFPContractMode()) {
400  // Preserve any contraction performed by the front-end. (Strict performs
401  // splitting of the muladd instrinsic in the backend.)
402  Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
403  break;
404  case LangOptions::FPC_On:
405  Options.AllowFPOpFusion = llvm::FPOpFusion::Standard;
406  break;
408  Options.AllowFPOpFusion = llvm::FPOpFusion::Fast;
409  break;
410  }
411 
412  Options.UseInitArray = CodeGenOpts.UseInitArray;
413  Options.DisableIntegratedAS = CodeGenOpts.DisableIntegratedAS;
414  Options.CompressDebugSections = CodeGenOpts.getCompressDebugSections();
415  Options.RelaxELFRelocations = CodeGenOpts.RelaxELFRelocations;
416 
417  // Set EABI version.
418  Options.EABIVersion = TargetOpts.EABIVersion;
419 
420  if (LangOpts.SjLjExceptions)
421  Options.ExceptionModel = llvm::ExceptionHandling::SjLj;
422 
423  Options.NoInfsFPMath = CodeGenOpts.NoInfsFPMath;
424  Options.NoNaNsFPMath = CodeGenOpts.NoNaNsFPMath;
425  Options.NoZerosInBSS = CodeGenOpts.NoZeroInitializedInBSS;
426  Options.UnsafeFPMath = CodeGenOpts.UnsafeFPMath;
427  Options.StackAlignmentOverride = CodeGenOpts.StackAlignment;
428  Options.FunctionSections = CodeGenOpts.FunctionSections;
429  Options.DataSections = CodeGenOpts.DataSections;
430  Options.UniqueSectionNames = CodeGenOpts.UniqueSectionNames;
431  Options.EmulatedTLS = CodeGenOpts.EmulatedTLS;
432  Options.DebuggerTuning = CodeGenOpts.getDebuggerTuning();
433 
434  if (CodeGenOpts.EnableSplitDwarf)
435  Options.MCOptions.SplitDwarfFile = CodeGenOpts.SplitDwarfFile;
436  Options.MCOptions.MCRelaxAll = CodeGenOpts.RelaxAll;
437  Options.MCOptions.MCSaveTempLabels = CodeGenOpts.SaveTempLabels;
438  Options.MCOptions.MCUseDwarfDirectory = !CodeGenOpts.NoDwarfDirectoryAsm;
439  Options.MCOptions.MCNoExecStack = CodeGenOpts.NoExecStack;
440  Options.MCOptions.MCIncrementalLinkerCompatible =
441  CodeGenOpts.IncrementalLinkerCompatible;
442  Options.MCOptions.MCPIECopyRelocations = CodeGenOpts.PIECopyRelocations;
443  Options.MCOptions.MCFatalWarnings = CodeGenOpts.FatalWarnings;
444  Options.MCOptions.AsmVerbose = CodeGenOpts.AsmVerbose;
445  Options.MCOptions.PreserveAsmComments = CodeGenOpts.PreserveAsmComments;
446  Options.MCOptions.ABIName = TargetOpts.ABI;
447  for (const auto &Entry : HSOpts.UserEntries)
448  if (!Entry.IsFramework &&
449  (Entry.Group == frontend::IncludeDirGroup::Quoted ||
450  Entry.Group == frontend::IncludeDirGroup::Angled ||
451  Entry.Group == frontend::IncludeDirGroup::System))
452  Options.MCOptions.IASSearchPaths.push_back(
453  Entry.IgnoreSysRoot ? Entry.Path : HSOpts.Sysroot + Entry.Path);
454 }
455 
456 void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM,
457  legacy::FunctionPassManager &FPM) {
458  // Handle disabling of all LLVM passes, where we want to preserve the
459  // internal module before any optimization.
460  if (CodeGenOpts.DisableLLVMPasses)
461  return;
462 
463  // Figure out TargetLibraryInfo. This needs to be added to MPM and FPM
464  // manually (and not via PMBuilder), since some passes (eg. InstrProfiling)
465  // are inserted before PMBuilder ones - they'd get the default-constructed
466  // TLI with an unknown target otherwise.
467  Triple TargetTriple(TheModule->getTargetTriple());
468  std::unique_ptr<TargetLibraryInfoImpl> TLII(
469  createTLII(TargetTriple, CodeGenOpts));
470 
471  PassManagerBuilderWrapper PMBuilder(TargetTriple, CodeGenOpts, LangOpts);
472 
473  // At O0 and O1 we only run the always inliner which is more efficient. At
474  // higher optimization levels we run the normal inliner.
475  if (CodeGenOpts.OptimizationLevel <= 1) {
476  bool InsertLifetimeIntrinsics = (CodeGenOpts.OptimizationLevel != 0 &&
477  !CodeGenOpts.DisableLifetimeMarkers);
478  PMBuilder.Inliner = createAlwaysInlinerLegacyPass(InsertLifetimeIntrinsics);
479  } else {
480  // We do not want to inline hot callsites for SamplePGO module-summary build
481  // because profile annotation will happen again in ThinLTO backend, and we
482  // want the IR of the hot path to match the profile.
483  PMBuilder.Inliner = createFunctionInliningPass(
484  CodeGenOpts.OptimizationLevel, CodeGenOpts.OptimizeSize,
485  (!CodeGenOpts.SampleProfileFile.empty() &&
486  CodeGenOpts.EmitSummaryIndex));
487  }
488 
489  PMBuilder.OptLevel = CodeGenOpts.OptimizationLevel;
490  PMBuilder.SizeLevel = CodeGenOpts.OptimizeSize;
491  PMBuilder.SLPVectorize = CodeGenOpts.VectorizeSLP;
492  PMBuilder.LoopVectorize = CodeGenOpts.VectorizeLoop;
493 
494  PMBuilder.DisableUnrollLoops = !CodeGenOpts.UnrollLoops;
495  PMBuilder.MergeFunctions = CodeGenOpts.MergeFunctions;
496  PMBuilder.PrepareForThinLTO = CodeGenOpts.EmitSummaryIndex;
497  PMBuilder.PrepareForLTO = CodeGenOpts.PrepareForLTO;
498  PMBuilder.RerollLoops = CodeGenOpts.RerollLoops;
499 
500  MPM.add(new TargetLibraryInfoWrapperPass(*TLII));
501 
502  if (TM)
503  TM->adjustPassManager(PMBuilder);
504 
505  if (CodeGenOpts.DebugInfoForProfiling ||
506  !CodeGenOpts.SampleProfileFile.empty())
507  PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
509 
510  // In ObjC ARC mode, add the main ARC optimization passes.
511  if (LangOpts.ObjCAutoRefCount) {
512  PMBuilder.addExtension(PassManagerBuilder::EP_EarlyAsPossible,
514  PMBuilder.addExtension(PassManagerBuilder::EP_ModuleOptimizerEarly,
516  PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
518  }
519 
520  if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds)) {
521  PMBuilder.addExtension(PassManagerBuilder::EP_ScalarOptimizerLate,
523  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
525  }
526 
527  if (CodeGenOpts.SanitizeCoverageType ||
528  CodeGenOpts.SanitizeCoverageIndirectCalls ||
529  CodeGenOpts.SanitizeCoverageTraceCmp) {
530  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
532  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
534  }
535 
536  if (LangOpts.Sanitize.has(SanitizerKind::Address)) {
537  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
539  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
541  }
542 
543  if (LangOpts.Sanitize.has(SanitizerKind::KernelAddress)) {
544  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
546  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
548  }
549 
550  if (LangOpts.Sanitize.has(SanitizerKind::Memory)) {
551  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
553  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
555  }
556 
557  if (LangOpts.Sanitize.has(SanitizerKind::Thread)) {
558  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
560  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
562  }
563 
564  if (LangOpts.Sanitize.has(SanitizerKind::DataFlow)) {
565  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
567  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
569  }
570 
571  if (LangOpts.CoroutinesTS)
572  addCoroutinePassesToExtensionPoints(PMBuilder);
573 
574  if (LangOpts.Sanitize.hasOneOf(SanitizerKind::Efficiency)) {
575  PMBuilder.addExtension(PassManagerBuilder::EP_OptimizerLast,
577  PMBuilder.addExtension(PassManagerBuilder::EP_EnabledOnOptLevel0,
579  }
580 
581  // Set up the per-function pass manager.
582  FPM.add(new TargetLibraryInfoWrapperPass(*TLII));
583  if (CodeGenOpts.VerifyModule)
584  FPM.add(createVerifierPass());
585 
586  // Set up the per-module pass manager.
587  if (!CodeGenOpts.RewriteMapFiles.empty())
588  addSymbolRewriterPass(CodeGenOpts, &MPM);
589 
590  if (!CodeGenOpts.DisableGCov &&
591  (CodeGenOpts.EmitGcovArcs || CodeGenOpts.EmitGcovNotes)) {
592  // Not using 'GCOVOptions::getDefault' allows us to avoid exiting if
593  // LLVM's -default-gcov-version flag is set to something invalid.
594  GCOVOptions Options;
595  Options.EmitNotes = CodeGenOpts.EmitGcovNotes;
596  Options.EmitData = CodeGenOpts.EmitGcovArcs;
597  memcpy(Options.Version, CodeGenOpts.CoverageVersion, 4);
598  Options.UseCfgChecksum = CodeGenOpts.CoverageExtraChecksum;
599  Options.NoRedZone = CodeGenOpts.DisableRedZone;
600  Options.FunctionNamesInData =
601  !CodeGenOpts.CoverageNoFunctionNamesInData;
602  Options.ExitBlockBeforeBody = CodeGenOpts.CoverageExitBlockBeforeBody;
603  MPM.add(createGCOVProfilerPass(Options));
604  if (CodeGenOpts.getDebugInfo() == codegenoptions::NoDebugInfo)
605  MPM.add(createStripSymbolsPass(true));
606  }
607 
608  if (CodeGenOpts.hasProfileClangInstr()) {
609  InstrProfOptions Options;
610  Options.NoRedZone = CodeGenOpts.DisableRedZone;
611  Options.InstrProfileOutput = CodeGenOpts.InstrProfileOutput;
612  MPM.add(createInstrProfilingLegacyPass(Options));
613  }
614  if (CodeGenOpts.hasProfileIRInstr()) {
615  PMBuilder.EnablePGOInstrGen = true;
616  if (!CodeGenOpts.InstrProfileOutput.empty())
617  PMBuilder.PGOInstrGen = CodeGenOpts.InstrProfileOutput;
618  else
619  PMBuilder.PGOInstrGen = DefaultProfileGenName;
620  }
621  if (CodeGenOpts.hasProfileIRUse())
622  PMBuilder.PGOInstrUse = CodeGenOpts.ProfileInstrumentUsePath;
623 
624  if (!CodeGenOpts.SampleProfileFile.empty())
625  PMBuilder.PGOSampleUse = CodeGenOpts.SampleProfileFile;
626 
627  PMBuilder.populateFunctionPassManager(FPM);
628  PMBuilder.populateModulePassManager(MPM);
629 }
630 
631 static void setCommandLineOpts(const CodeGenOptions &CodeGenOpts) {
632  SmallVector<const char *, 16> BackendArgs;
633  BackendArgs.push_back("clang"); // Fake program name.
634  if (!CodeGenOpts.DebugPass.empty()) {
635  BackendArgs.push_back("-debug-pass");
636  BackendArgs.push_back(CodeGenOpts.DebugPass.c_str());
637  }
638  if (!CodeGenOpts.LimitFloatPrecision.empty()) {
639  BackendArgs.push_back("-limit-float-precision");
640  BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
641  }
642  for (const std::string &BackendOption : CodeGenOpts.BackendOptions)
643  BackendArgs.push_back(BackendOption.c_str());
644  BackendArgs.push_back(nullptr);
645  llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
646  BackendArgs.data());
647 }
648 
649 void EmitAssemblyHelper::CreateTargetMachine(bool MustCreateTM) {
650  // Create the TargetMachine for generating code.
651  std::string Error;
652  std::string Triple = TheModule->getTargetTriple();
653  const llvm::Target *TheTarget = TargetRegistry::lookupTarget(Triple, Error);
654  if (!TheTarget) {
655  if (MustCreateTM)
656  Diags.Report(diag::err_fe_unable_to_create_target) << Error;
657  return;
658  }
659 
660  llvm::CodeModel::Model CM = getCodeModel(CodeGenOpts);
661  std::string FeaturesStr =
662  llvm::join(TargetOpts.Features.begin(), TargetOpts.Features.end(), ",");
663  llvm::Reloc::Model RM = getRelocModel(CodeGenOpts);
664  CodeGenOpt::Level OptLevel = getCGOptLevel(CodeGenOpts);
665 
666  llvm::TargetOptions Options;
667  initTargetOptions(Options, CodeGenOpts, TargetOpts, LangOpts, HSOpts);
668  TM.reset(TheTarget->createTargetMachine(Triple, TargetOpts.CPU, FeaturesStr,
669  Options, RM, CM, OptLevel));
670 }
671 
672 bool EmitAssemblyHelper::AddEmitPasses(legacy::PassManager &CodeGenPasses,
674  raw_pwrite_stream &OS) {
675  // Add LibraryInfo.
676  llvm::Triple TargetTriple(TheModule->getTargetTriple());
677  std::unique_ptr<TargetLibraryInfoImpl> TLII(
678  createTLII(TargetTriple, CodeGenOpts));
679  CodeGenPasses.add(new TargetLibraryInfoWrapperPass(*TLII));
680 
681  // Normal mode, emit a .s or .o file by running the code generator. Note,
682  // this also adds codegenerator level optimization passes.
683  TargetMachine::CodeGenFileType CGFT = getCodeGenFileType(Action);
684 
685  // Add ObjC ARC final-cleanup optimizations. This is done as part of the
686  // "codegen" passes so that it isn't run multiple times when there is
687  // inlining happening.
688  if (CodeGenOpts.OptimizationLevel > 0)
689  CodeGenPasses.add(createObjCARCContractPass());
690 
691  if (TM->addPassesToEmitFile(CodeGenPasses, OS, CGFT,
692  /*DisableVerify=*/!CodeGenOpts.VerifyModule)) {
693  Diags.Report(diag::err_fe_unable_to_interface_with_target);
694  return false;
695  }
696 
697  return true;
698 }
699 
701  std::unique_ptr<raw_pwrite_stream> OS) {
702  TimeRegion Region(llvm::TimePassesIsEnabled ? &CodeGenerationTime : nullptr);
703 
704  setCommandLineOpts(CodeGenOpts);
705 
706  bool UsesCodeGen = (Action != Backend_EmitNothing &&
707  Action != Backend_EmitBC &&
708  Action != Backend_EmitLL);
709  CreateTargetMachine(UsesCodeGen);
710 
711  if (UsesCodeGen && !TM)
712  return;
713  if (TM)
714  TheModule->setDataLayout(TM->createDataLayout());
715 
716  legacy::PassManager PerModulePasses;
717  PerModulePasses.add(
718  createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
719 
720  legacy::FunctionPassManager PerFunctionPasses(TheModule);
721  PerFunctionPasses.add(
722  createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
723 
724  CreatePasses(PerModulePasses, PerFunctionPasses);
725 
726  legacy::PassManager CodeGenPasses;
727  CodeGenPasses.add(
728  createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
729 
730  std::unique_ptr<raw_fd_ostream> ThinLinkOS;
731 
732  switch (Action) {
733  case Backend_EmitNothing:
734  break;
735 
736  case Backend_EmitBC:
737  if (CodeGenOpts.EmitSummaryIndex) {
738  if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
739  std::error_code EC;
740  ThinLinkOS.reset(new llvm::raw_fd_ostream(
741  CodeGenOpts.ThinLinkBitcodeFile, EC,
742  llvm::sys::fs::F_None));
743  if (EC) {
744  Diags.Report(diag::err_fe_unable_to_open_output) << CodeGenOpts.ThinLinkBitcodeFile
745  << EC.message();
746  return;
747  }
748  }
749  PerModulePasses.add(
750  createWriteThinLTOBitcodePass(*OS, ThinLinkOS.get()));
751  }
752  else
753  PerModulePasses.add(
754  createBitcodeWriterPass(*OS, CodeGenOpts.EmitLLVMUseLists));
755  break;
756 
757  case Backend_EmitLL:
758  PerModulePasses.add(
759  createPrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
760  break;
761 
762  default:
763  if (!AddEmitPasses(CodeGenPasses, Action, *OS))
764  return;
765  }
766 
767  // Before executing passes, print the final values of the LLVM options.
768  cl::PrintOptionValues();
769 
770  // Run passes. For now we do all passes at once, but eventually we
771  // would like to have the option of streaming code generation.
772 
773  {
774  PrettyStackTraceString CrashInfo("Per-function optimization");
775 
776  PerFunctionPasses.doInitialization();
777  for (Function &F : *TheModule)
778  if (!F.isDeclaration())
779  PerFunctionPasses.run(F);
780  PerFunctionPasses.doFinalization();
781  }
782 
783  {
784  PrettyStackTraceString CrashInfo("Per-module optimization passes");
785  PerModulePasses.run(*TheModule);
786  }
787 
788  {
789  PrettyStackTraceString CrashInfo("Code generation");
790  CodeGenPasses.run(*TheModule);
791  }
792 }
793 
794 static PassBuilder::OptimizationLevel mapToLevel(const CodeGenOptions &Opts) {
795  switch (Opts.OptimizationLevel) {
796  default:
797  llvm_unreachable("Invalid optimization level!");
798 
799  case 1:
800  return PassBuilder::O1;
801 
802  case 2:
803  switch (Opts.OptimizeSize) {
804  default:
805  llvm_unreachable("Invalide optimization level for size!");
806 
807  case 0:
808  return PassBuilder::O2;
809 
810  case 1:
811  return PassBuilder::Os;
812 
813  case 2:
814  return PassBuilder::Oz;
815  }
816 
817  case 3:
818  return PassBuilder::O3;
819  }
820 }
821 
822 /// A clean version of `EmitAssembly` that uses the new pass manager.
823 ///
824 /// Not all features are currently supported in this system, but where
825 /// necessary it falls back to the legacy pass manager to at least provide
826 /// basic functionality.
827 ///
828 /// This API is planned to have its functionality finished and then to replace
829 /// `EmitAssembly` at some point in the future when the default switches.
830 void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
831  BackendAction Action, std::unique_ptr<raw_pwrite_stream> OS) {
832  TimeRegion Region(llvm::TimePassesIsEnabled ? &CodeGenerationTime : nullptr);
833  setCommandLineOpts(CodeGenOpts);
834 
835  // The new pass manager always makes a target machine available to passes
836  // during construction.
837  CreateTargetMachine(/*MustCreateTM*/ true);
838  if (!TM)
839  // This will already be diagnosed, just bail.
840  return;
841  TheModule->setDataLayout(TM->createDataLayout());
842 
843  PGOOptions PGOOpt;
844 
845  // -fprofile-generate.
846  PGOOpt.RunProfileGen = CodeGenOpts.hasProfileIRInstr();
847  if (PGOOpt.RunProfileGen)
848  PGOOpt.ProfileGenFile = CodeGenOpts.InstrProfileOutput.empty() ?
849  DefaultProfileGenName : CodeGenOpts.InstrProfileOutput;
850 
851  // -fprofile-use.
852  if (CodeGenOpts.hasProfileIRUse())
853  PGOOpt.ProfileUseFile = CodeGenOpts.ProfileInstrumentUsePath;
854 
855  if (!CodeGenOpts.SampleProfileFile.empty())
856  PGOOpt.SampleProfileFile = CodeGenOpts.SampleProfileFile;
857 
858  // Only pass a PGO options struct if -fprofile-generate or
859  // -fprofile-use were passed on the cmdline.
860  PassBuilder PB(TM.get(),
861  (PGOOpt.RunProfileGen ||
862  !PGOOpt.ProfileUseFile.empty() ||
863  !PGOOpt.SampleProfileFile.empty()) ?
864  Optional<PGOOptions>(PGOOpt) : None);
865 
866  LoopAnalysisManager LAM;
867  FunctionAnalysisManager FAM;
868  CGSCCAnalysisManager CGAM;
869  ModuleAnalysisManager MAM;
870 
871  // Register the AA manager first so that our version is the one used.
872  FAM.registerPass([&] { return PB.buildDefaultAAPipeline(); });
873 
874  // Register all the basic analyses with the managers.
875  PB.registerModuleAnalyses(MAM);
876  PB.registerCGSCCAnalyses(CGAM);
877  PB.registerFunctionAnalyses(FAM);
878  PB.registerLoopAnalyses(LAM);
879  PB.crossRegisterProxies(LAM, FAM, CGAM, MAM);
880 
881  ModulePassManager MPM(CodeGenOpts.DebugPassManager);
882 
883  if (!CodeGenOpts.DisableLLVMPasses) {
884  bool IsThinLTO = CodeGenOpts.EmitSummaryIndex;
885  bool IsLTO = CodeGenOpts.PrepareForLTO;
886 
887  if (CodeGenOpts.OptimizationLevel == 0) {
888  // Build a minimal pipeline based on the semantics required by Clang,
889  // which is just that always inlining occurs.
890  MPM.addPass(AlwaysInlinerPass());
891  if (IsThinLTO)
892  MPM.addPass(NameAnonGlobalPass());
893  } else {
894  // Map our optimization levels into one of the distinct levels used to
895  // configure the pipeline.
896  PassBuilder::OptimizationLevel Level = mapToLevel(CodeGenOpts);
897 
898  if (IsThinLTO) {
899  MPM = PB.buildThinLTOPreLinkDefaultPipeline(
900  Level, CodeGenOpts.DebugPassManager);
901  MPM.addPass(NameAnonGlobalPass());
902  } else if (IsLTO) {
903  MPM = PB.buildLTOPreLinkDefaultPipeline(Level,
904  CodeGenOpts.DebugPassManager);
905  } else {
906  MPM = PB.buildPerModuleDefaultPipeline(Level,
907  CodeGenOpts.DebugPassManager);
908  }
909  }
910  }
911 
912  // FIXME: We still use the legacy pass manager to do code generation. We
913  // create that pass manager here and use it as needed below.
914  legacy::PassManager CodeGenPasses;
915  bool NeedCodeGen = false;
916  Optional<raw_fd_ostream> ThinLinkOS;
917 
918  // Append any output we need to the pass manager.
919  switch (Action) {
920  case Backend_EmitNothing:
921  break;
922 
923  case Backend_EmitBC:
924  if (CodeGenOpts.EmitSummaryIndex) {
925  if (!CodeGenOpts.ThinLinkBitcodeFile.empty()) {
926  std::error_code EC;
927  ThinLinkOS.emplace(CodeGenOpts.ThinLinkBitcodeFile, EC,
928  llvm::sys::fs::F_None);
929  if (EC) {
930  Diags.Report(diag::err_fe_unable_to_open_output)
931  << CodeGenOpts.ThinLinkBitcodeFile << EC.message();
932  return;
933  }
934  }
935  MPM.addPass(
936  ThinLTOBitcodeWriterPass(*OS, ThinLinkOS ? &*ThinLinkOS : nullptr));
937  } else {
938  MPM.addPass(BitcodeWriterPass(*OS, CodeGenOpts.EmitLLVMUseLists,
939  CodeGenOpts.EmitSummaryIndex,
940  CodeGenOpts.EmitSummaryIndex));
941  }
942  break;
943 
944  case Backend_EmitLL:
945  MPM.addPass(PrintModulePass(*OS, "", CodeGenOpts.EmitLLVMUseLists));
946  break;
947 
949  case Backend_EmitMCNull:
950  case Backend_EmitObj:
951  NeedCodeGen = true;
952  CodeGenPasses.add(
953  createTargetTransformInfoWrapperPass(getTargetIRAnalysis()));
954  if (!AddEmitPasses(CodeGenPasses, Action, *OS))
955  // FIXME: Should we handle this error differently?
956  return;
957  break;
958  }
959 
960  // Before executing passes, print the final values of the LLVM options.
961  cl::PrintOptionValues();
962 
963  // Now that we have all of the passes ready, run them.
964  {
965  PrettyStackTraceString CrashInfo("Optimizer");
966  MPM.run(*TheModule, MAM);
967  }
968 
969  // Now if needed, run the legacy PM for codegen.
970  if (NeedCodeGen) {
971  PrettyStackTraceString CrashInfo("Code generation");
972  CodeGenPasses.run(*TheModule);
973  }
974 }
975 
976 Expected<BitcodeModule> clang::FindThinLTOModule(MemoryBufferRef MBRef) {
977  Expected<std::vector<BitcodeModule>> BMsOrErr = getBitcodeModuleList(MBRef);
978  if (!BMsOrErr)
979  return BMsOrErr.takeError();
980 
981  // The bitcode file may contain multiple modules, we want the one that is
982  // marked as being the ThinLTO module.
983  for (BitcodeModule &BM : *BMsOrErr) {
984  Expected<BitcodeLTOInfo> LTOInfo = BM.getLTOInfo();
985  if (LTOInfo && LTOInfo->IsThinLTO)
986  return BM;
987  }
988 
989  return make_error<StringError>("Could not find module summary",
990  inconvertibleErrorCode());
991 }
992 
993 static void runThinLTOBackend(ModuleSummaryIndex *CombinedIndex, Module *M,
994  const HeaderSearchOptions &HeaderOpts,
995  const CodeGenOptions &CGOpts,
996  const clang::TargetOptions &TOpts,
997  const LangOptions &LOpts,
998  std::unique_ptr<raw_pwrite_stream> OS,
999  std::string SampleProfile,
1000  BackendAction Action) {
1001  StringMap<DenseMap<GlobalValue::GUID, GlobalValueSummary *>>
1002  ModuleToDefinedGVSummaries;
1003  CombinedIndex->collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
1004 
1005  setCommandLineOpts(CGOpts);
1006 
1007  // We can simply import the values mentioned in the combined index, since
1008  // we should only invoke this using the individual indexes written out
1009  // via a WriteIndexesThinBackend.
1010  FunctionImporter::ImportMapTy ImportList;
1011  for (auto &GlobalList : *CombinedIndex) {
1012  // Ignore entries for undefined references.
1013  if (GlobalList.second.SummaryList.empty())
1014  continue;
1015 
1016  auto GUID = GlobalList.first;
1017  assert(GlobalList.second.SummaryList.size() == 1 &&
1018  "Expected individual combined index to have one summary per GUID");
1019  auto &Summary = GlobalList.second.SummaryList[0];
1020  // Skip the summaries for the importing module. These are included to
1021  // e.g. record required linkage changes.
1022  if (Summary->modulePath() == M->getModuleIdentifier())
1023  continue;
1024  // Doesn't matter what value we plug in to the map, just needs an entry
1025  // to provoke importing by thinBackend.
1026  ImportList[Summary->modulePath()][GUID] = 1;
1027  }
1028 
1029  std::vector<std::unique_ptr<llvm::MemoryBuffer>> OwnedImports;
1030  MapVector<llvm::StringRef, llvm::BitcodeModule> ModuleMap;
1031 
1032  for (auto &I : ImportList) {
1033  ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> MBOrErr =
1034  llvm::MemoryBuffer::getFile(I.first());
1035  if (!MBOrErr) {
1036  errs() << "Error loading imported file '" << I.first()
1037  << "': " << MBOrErr.getError().message() << "\n";
1038  return;
1039  }
1040 
1041  Expected<BitcodeModule> BMOrErr = FindThinLTOModule(**MBOrErr);
1042  if (!BMOrErr) {
1043  handleAllErrors(BMOrErr.takeError(), [&](ErrorInfoBase &EIB) {
1044  errs() << "Error loading imported file '" << I.first()
1045  << "': " << EIB.message() << '\n';
1046  });
1047  return;
1048  }
1049  ModuleMap.insert({I.first(), *BMOrErr});
1050 
1051  OwnedImports.push_back(std::move(*MBOrErr));
1052  }
1053  auto AddStream = [&](size_t Task) {
1054  return llvm::make_unique<lto::NativeObjectStream>(std::move(OS));
1055  };
1056  lto::Config Conf;
1057  Conf.CPU = TOpts.CPU;
1058  Conf.CodeModel = getCodeModel(CGOpts);
1059  Conf.MAttrs = TOpts.Features;
1060  Conf.RelocModel = getRelocModel(CGOpts);
1061  Conf.CGOptLevel = getCGOptLevel(CGOpts);
1062  initTargetOptions(Conf.Options, CGOpts, TOpts, LOpts, HeaderOpts);
1063  Conf.SampleProfile = std::move(SampleProfile);
1064  Conf.UseNewPM = CGOpts.ExperimentalNewPassManager;
1065  switch (Action) {
1066  case Backend_EmitNothing:
1067  Conf.PreCodeGenModuleHook = [](size_t Task, const Module &Mod) {
1068  return false;
1069  };
1070  break;
1071  case Backend_EmitLL:
1072  Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1073  M->print(*OS, nullptr, CGOpts.EmitLLVMUseLists);
1074  return false;
1075  };
1076  break;
1077  case Backend_EmitBC:
1078  Conf.PreCodeGenModuleHook = [&](size_t Task, const Module &Mod) {
1079  WriteBitcodeToFile(M, *OS, CGOpts.EmitLLVMUseLists);
1080  return false;
1081  };
1082  break;
1083  default:
1084  Conf.CGFileType = getCodeGenFileType(Action);
1085  break;
1086  }
1087  if (Error E = thinBackend(
1088  Conf, 0, AddStream, *M, *CombinedIndex, ImportList,
1089  ModuleToDefinedGVSummaries[M->getModuleIdentifier()], ModuleMap)) {
1090  handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1091  errs() << "Error running ThinLTO backend: " << EIB.message() << '\n';
1092  });
1093  }
1094 }
1095 
1097  const HeaderSearchOptions &HeaderOpts,
1098  const CodeGenOptions &CGOpts,
1099  const clang::TargetOptions &TOpts,
1100  const LangOptions &LOpts,
1101  const llvm::DataLayout &TDesc, Module *M,
1102  BackendAction Action,
1103  std::unique_ptr<raw_pwrite_stream> OS) {
1104  if (!CGOpts.ThinLTOIndexFile.empty()) {
1105  // If we are performing a ThinLTO importing compile, load the function index
1106  // into memory and pass it into runThinLTOBackend, which will run the
1107  // function importer and invoke LTO passes.
1109  llvm::getModuleSummaryIndexForFile(CGOpts.ThinLTOIndexFile,
1110  /*IgnoreEmptyThinLTOIndexFile*/true);
1111  if (!IndexOrErr) {
1112  logAllUnhandledErrors(IndexOrErr.takeError(), errs(),
1113  "Error loading index file '" +
1114  CGOpts.ThinLTOIndexFile + "': ");
1115  return;
1116  }
1117  std::unique_ptr<ModuleSummaryIndex> CombinedIndex = std::move(*IndexOrErr);
1118  // A null CombinedIndex means we should skip ThinLTO compilation
1119  // (LLVM will optionally ignore empty index files, returning null instead
1120  // of an error).
1121  bool DoThinLTOBackend = CombinedIndex != nullptr;
1122  if (DoThinLTOBackend) {
1123  runThinLTOBackend(CombinedIndex.get(), M, HeaderOpts, CGOpts, TOpts,
1124  LOpts, std::move(OS), CGOpts.SampleProfileFile, Action);
1125  return;
1126  }
1127  }
1128 
1129  EmitAssemblyHelper AsmHelper(Diags, HeaderOpts, CGOpts, TOpts, LOpts, M);
1130 
1131  if (CGOpts.ExperimentalNewPassManager)
1132  AsmHelper.EmitAssemblyWithNewPassManager(Action, std::move(OS));
1133  else
1134  AsmHelper.EmitAssembly(Action, std::move(OS));
1135 
1136  // Verify clang's TargetInfo DataLayout against the LLVM TargetMachine's
1137  // DataLayout.
1138  if (AsmHelper.TM) {
1139  std::string DLDesc = M->getDataLayout().getStringRepresentation();
1140  if (DLDesc != TDesc.getStringRepresentation()) {
1141  unsigned DiagID = Diags.getCustomDiagID(
1142  DiagnosticsEngine::Error, "backend data layout '%0' does not match "
1143  "expected target description '%1'");
1144  Diags.Report(DiagID) << DLDesc << TDesc.getStringRepresentation();
1145  }
1146  }
1147 }
1148 
1149 static const char* getSectionNameForBitcode(const Triple &T) {
1150  switch (T.getObjectFormat()) {
1151  case Triple::MachO:
1152  return "__LLVM,__bitcode";
1153  case Triple::COFF:
1154  case Triple::ELF:
1155  case Triple::Wasm:
1156  case Triple::UnknownObjectFormat:
1157  return ".llvmbc";
1158  }
1159  llvm_unreachable("Unimplemented ObjectFormatType");
1160 }
1161 
1162 static const char* getSectionNameForCommandline(const Triple &T) {
1163  switch (T.getObjectFormat()) {
1164  case Triple::MachO:
1165  return "__LLVM,__cmdline";
1166  case Triple::COFF:
1167  case Triple::ELF:
1168  case Triple::Wasm:
1169  case Triple::UnknownObjectFormat:
1170  return ".llvmcmd";
1171  }
1172  llvm_unreachable("Unimplemented ObjectFormatType");
1173 }
1174 
1175 // With -fembed-bitcode, save a copy of the llvm IR as data in the
1176 // __LLVM,__bitcode section.
1177 void clang::EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts,
1178  llvm::MemoryBufferRef Buf) {
1179  if (CGOpts.getEmbedBitcode() == CodeGenOptions::Embed_Off)
1180  return;
1181 
1182  // Save llvm.compiler.used and remote it.
1183  SmallVector<Constant*, 2> UsedArray;
1184  SmallSet<GlobalValue*, 4> UsedGlobals;
1185  Type *UsedElementType = Type::getInt8Ty(M->getContext())->getPointerTo(0);
1186  GlobalVariable *Used = collectUsedGlobalVariables(*M, UsedGlobals, true);
1187  for (auto *GV : UsedGlobals) {
1188  if (GV->getName() != "llvm.embedded.module" &&
1189  GV->getName() != "llvm.cmdline")
1190  UsedArray.push_back(
1191  ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
1192  }
1193  if (Used)
1194  Used->eraseFromParent();
1195 
1196  // Embed the bitcode for the llvm module.
1197  std::string Data;
1198  ArrayRef<uint8_t> ModuleData;
1199  Triple T(M->getTargetTriple());
1200  // Create a constant that contains the bitcode.
1201  // In case of embedding a marker, ignore the input Buf and use the empty
1202  // ArrayRef. It is also legal to create a bitcode marker even Buf is empty.
1203  if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Marker) {
1204  if (!isBitcode((const unsigned char *)Buf.getBufferStart(),
1205  (const unsigned char *)Buf.getBufferEnd())) {
1206  // If the input is LLVM Assembly, bitcode is produced by serializing
1207  // the module. Use-lists order need to be perserved in this case.
1208  llvm::raw_string_ostream OS(Data);
1209  llvm::WriteBitcodeToFile(M, OS, /* ShouldPreserveUseListOrder */ true);
1210  ModuleData =
1211  ArrayRef<uint8_t>((const uint8_t *)OS.str().data(), OS.str().size());
1212  } else
1213  // If the input is LLVM bitcode, write the input byte stream directly.
1214  ModuleData = ArrayRef<uint8_t>((const uint8_t *)Buf.getBufferStart(),
1215  Buf.getBufferSize());
1216  }
1217  llvm::Constant *ModuleConstant =
1218  llvm::ConstantDataArray::get(M->getContext(), ModuleData);
1219  llvm::GlobalVariable *GV = new llvm::GlobalVariable(
1220  *M, ModuleConstant->getType(), true, llvm::GlobalValue::PrivateLinkage,
1221  ModuleConstant);
1222  GV->setSection(getSectionNameForBitcode(T));
1223  UsedArray.push_back(
1224  ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
1225  if (llvm::GlobalVariable *Old =
1226  M->getGlobalVariable("llvm.embedded.module", true)) {
1227  assert(Old->hasOneUse() &&
1228  "llvm.embedded.module can only be used once in llvm.compiler.used");
1229  GV->takeName(Old);
1230  Old->eraseFromParent();
1231  } else {
1232  GV->setName("llvm.embedded.module");
1233  }
1234 
1235  // Skip if only bitcode needs to be embedded.
1236  if (CGOpts.getEmbedBitcode() != CodeGenOptions::Embed_Bitcode) {
1237  // Embed command-line options.
1238  ArrayRef<uint8_t> CmdData(const_cast<uint8_t *>(CGOpts.CmdArgs.data()),
1239  CGOpts.CmdArgs.size());
1240  llvm::Constant *CmdConstant =
1241  llvm::ConstantDataArray::get(M->getContext(), CmdData);
1242  GV = new llvm::GlobalVariable(*M, CmdConstant->getType(), true,
1243  llvm::GlobalValue::PrivateLinkage,
1244  CmdConstant);
1245  GV->setSection(getSectionNameForCommandline(T));
1246  UsedArray.push_back(
1247  ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, UsedElementType));
1248  if (llvm::GlobalVariable *Old =
1249  M->getGlobalVariable("llvm.cmdline", true)) {
1250  assert(Old->hasOneUse() &&
1251  "llvm.cmdline can only be used once in llvm.compiler.used");
1252  GV->takeName(Old);
1253  Old->eraseFromParent();
1254  } else {
1255  GV->setName("llvm.cmdline");
1256  }
1257  }
1258 
1259  if (UsedArray.empty())
1260  return;
1261 
1262  // Recreate llvm.compiler.used.
1263  ArrayType *ATy = ArrayType::get(UsedElementType, UsedArray.size());
1264  auto *NewUsed = new GlobalVariable(
1265  *M, ATy, false, llvm::GlobalValue::AppendingLinkage,
1266  llvm::ConstantArray::get(ATy, UsedArray), "llvm.compiler.used");
1267  NewUsed->setSection("llvm.metadata");
1268 }
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 '#include <>' added by '-I'.
static void addObjCARCExpandPass(const PassManagerBuilder &Builder, PassManagerBase &PM)
Emit human-readable LLVM assembly.
Definition: BackendUtil.h:34
Run CodeGen, but don't emit anything.
Definition: BackendUtil.h:36
SanitizerSet Sanitize
Set of enabled sanitizers.
Definition: LangOptions.h:100
The base class of the type hierarchy.
Definition: Type.h:1303
DiagnosticBuilder Report(SourceLocation Loc, unsigned DiagID)
Issue the message to the client.
Definition: Diagnostic.h:1205
Represents an array type, per C99 6.7.5.2 - Array Declarators.
Definition: Type.h:2497
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'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'll break out.
std::string DebugPass
Enable additional debugging information.
SanitizerSet SanitizeRecover
Set of sanitizer checks that are non-fatal (i.e.
Emit LLVM bitcode files.
Definition: BackendUtil.h:33
std::vector< Entry > UserEntries
User specified include entries.
FrontendAction * Action
Definition: Tooling.cpp:205
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:57
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)
detail::InMemoryDirectory::const_iterator I
std::string FloatABI
The ABI to use for passing floating point arguments.
std::string ThreadModel
The thread model to use.
std::string LimitFloatPrecision
The float precision limit to use, if non-empty.
Defines the clang::LangOptions interface.
static void addObjCARCAPElimPass(const PassManagerBuilder &Builder, PassManagerBase &PM)
std::string RelocationModel
The name of the relocation model to use.
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
const MatchFinder::MatchFinderOptions & Options
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
void print(raw_ostream &OS, unsigned Indent=0) const
Print the module map for this module to the given stream.
Definition: Module.cpp:349
static void addKernelAddressSanitizerPasses(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
static void addSymbolRewriterPass(const CodeGenOptions &Opts, legacy::PassManager *MPM)
const std::vector< std::string > & getNoBuiltinFuncs() const
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 starting...
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:689
llvm::EABI EABIVersion
The EABI version to use.
Definition: TargetOptions.h:45
'#include ""' paths, added by 'gcc -iquote'.
std::string ThinLTOIndexFile
Name of the function summary index file to use for ThinLTO function importing.
building frameworks.
if(T->getSizeExpr()) TRY_TO(TraverseStmt(T-> getSizeExpr()))
static TargetMachine::CodeGenFileType getCodeGenFileType(BackendAction Action)
void EmbedBitcode(llvm::Module *M, const CodeGenOptions &CGOpts, llvm::MemoryBufferRef Buf)
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)
detail::InMemoryDirectory::const_iterator E
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)
bool has(SanitizerMask K) const
Check if a certain (single) sanitizer is enabled.
Definition: Sanitizers.h:50
static void addEfficiencySanitizerPass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
CodeGenOptions - Track various options which control how the code is optimized and passed to the back...
static llvm::CodeModel::Model getCodeModel(const CodeGenOptions &CodeGenOpts)
static void addObjCARCOptPass(const PassManagerBuilder &Builder, PassManagerBase &PM)
BoundNodesTreeBuilder *const Builder
StringLiteral - This represents a string literal expression, e.g.
Definition: Expr.h:1506
static void addAddDiscriminatorsPass(const PassManagerBuilder &Builder, legacy::PassManagerBase &PM)
HeaderSearchOptions - Helper class for storing options related to the initialization of the HeaderSea...
std::vector< std::string > SanitizerBlacklistFiles
Paths to blacklist files specifying which objects (files, functions, variables) should not be instrum...
Definition: LangOptions.h:104
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)