1//===--- CodeGenAction.cpp - LLVM Code Generation Frontend Action ---------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "clang/CodeGen/CodeGenAction.h"
10#include "CodeGenModule.h"
11#include "CoverageMappingGen.h"
12#include "MacroPPCallbacks.h"
13#include "clang/AST/ASTConsumer.h"
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/DeclCXX.h"
16#include "clang/AST/DeclGroup.h"
17#include "clang/Basic/DiagnosticFrontend.h"
18#include "clang/Basic/FileManager.h"
19#include "clang/Basic/LangStandard.h"
20#include "clang/Basic/SourceManager.h"
21#include "clang/Basic/TargetInfo.h"
22#include "clang/CodeGen/BackendUtil.h"
23#include "clang/CodeGen/ModuleBuilder.h"
24#include "clang/Driver/DriverDiagnostic.h"
25#include "clang/Frontend/CompilerInstance.h"
26#include "clang/Frontend/FrontendDiagnostic.h"
27#include "clang/Lex/Preprocessor.h"
28#include "llvm/Bitcode/BitcodeReader.h"
29#include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
30#include "llvm/IR/DebugInfo.h"
31#include "llvm/IR/DiagnosticInfo.h"
32#include "llvm/IR/DiagnosticPrinter.h"
33#include "llvm/IR/GlobalValue.h"
34#include "llvm/IR/LLVMContext.h"
35#include "llvm/IR/LLVMRemarkStreamer.h"
36#include "llvm/IR/Module.h"
37#include "llvm/IRReader/IRReader.h"
38#include "llvm/Linker/Linker.h"
39#include "llvm/Pass.h"
40#include "llvm/Support/MemoryBuffer.h"
41#include "llvm/Support/SourceMgr.h"
42#include "llvm/Support/TimeProfiler.h"
43#include "llvm/Support/Timer.h"
44#include "llvm/Support/ToolOutputFile.h"
45#include "llvm/Support/YAMLTraits.h"
46#include "llvm/Transforms/IPO/Internalize.h"
47
48#include <memory>
49using namespace clang;
50using namespace llvm;
51
52namespace clang {
53  class BackendConsumer;
54  class ClangDiagnosticHandler final : public DiagnosticHandler {
55  public:
56    ClangDiagnosticHandler(const CodeGenOptions &CGOpts, BackendConsumer *BCon)
57        : CodeGenOpts(CGOpts), BackendCon(BCon) {}
58
59    bool handleDiagnostics(const DiagnosticInfo &DI) override;
60
61    bool isAnalysisRemarkEnabled(StringRef PassName) const override {
62      return (CodeGenOpts.OptimizationRemarkAnalysisPattern &&
63              CodeGenOpts.OptimizationRemarkAnalysisPattern->match(PassName));
64    }
65    bool isMissedOptRemarkEnabled(StringRef PassName) const override {
66      return (CodeGenOpts.OptimizationRemarkMissedPattern &&
67              CodeGenOpts.OptimizationRemarkMissedPattern->match(PassName));
68    }
69    bool isPassedOptRemarkEnabled(StringRef PassName) const override {
70      return (CodeGenOpts.OptimizationRemarkPattern &&
71              CodeGenOpts.OptimizationRemarkPattern->match(PassName));
72    }
73
74    bool isAnyRemarkEnabled() const override {
75      return (CodeGenOpts.OptimizationRemarkAnalysisPattern ||
76              CodeGenOpts.OptimizationRemarkMissedPattern ||
77              CodeGenOpts.OptimizationRemarkPattern);
78    }
79
80  private:
81    const CodeGenOptions &CodeGenOpts;
82    BackendConsumer *BackendCon;
83  };
84
85  static void reportOptRecordError(Error E, DiagnosticsEngine &Diags,
86                                   const CodeGenOptions CodeGenOpts) {
87    handleAllErrors(
88        std::move(E),
89      [&](const LLVMRemarkSetupFileError &E) {
90          Diags.Report(diag::err_cannot_open_file)
91              << CodeGenOpts.OptRecordFile << E.message();
92        },
93      [&](const LLVMRemarkSetupPatternError &E) {
94          Diags.Report(diag::err_drv_optimization_remark_pattern)
95              << E.message() << CodeGenOpts.OptRecordPasses;
96        },
97      [&](const LLVMRemarkSetupFormatError &E) {
98          Diags.Report(diag::err_drv_optimization_remark_format)
99              << CodeGenOpts.OptRecordFormat;
100        });
101    }
102
103  class BackendConsumer : public ASTConsumer {
104    using LinkModule = CodeGenAction::LinkModule;
105
106    virtual void anchor();
107    DiagnosticsEngine &Diags;
108    BackendAction Action;
109    const HeaderSearchOptions &HeaderSearchOpts;
110    const CodeGenOptions &CodeGenOpts;
111    const TargetOptions &TargetOpts;
112    const LangOptions &LangOpts;
113    std::unique_ptr<raw_pwrite_stream> AsmOutStream;
114    ASTContext *Context;
115
116    Timer LLVMIRGeneration;
117    unsigned LLVMIRGenerationRefCount;
118
119    /// True if we've finished generating IR. This prevents us from generating
120    /// additional LLVM IR after emitting output in HandleTranslationUnit. This
121    /// can happen when Clang plugins trigger additional AST deserialization.
122    bool IRGenFinished = false;
123
124    std::unique_ptr<CodeGenerator> Gen;
125
126    SmallVector<LinkModule, 4> LinkModules;
127
128    // This is here so that the diagnostic printer knows the module a diagnostic
129    // refers to.
130    llvm::Module *CurLinkModule = nullptr;
131
132  public:
133    BackendConsumer(BackendAction Action, DiagnosticsEngine &Diags,
134                    const HeaderSearchOptions &HeaderSearchOpts,
135                    const PreprocessorOptions &PPOpts,
136                    const CodeGenOptions &CodeGenOpts,
137                    const TargetOptions &TargetOpts,
138                    const LangOptions &LangOpts, bool TimePasses,
139                    const std::string &InFile,
140                    SmallVector<LinkModule, 4> LinkModules,
141                    std::unique_ptr<raw_pwrite_stream> OS, LLVMContext &C,
142                    CoverageSourceInfo *CoverageInfo = nullptr)
143        : Diags(Diags), Action(Action), HeaderSearchOpts(HeaderSearchOpts),
144          CodeGenOpts(CodeGenOpts), TargetOpts(TargetOpts), LangOpts(LangOpts),
145          AsmOutStream(std::move(OS)), Context(nullptr),
146          LLVMIRGeneration("irgen", "LLVM IR Generation Time"),
147          LLVMIRGenerationRefCount(0),
148          Gen(CreateLLVMCodeGen(Diags, InFile, HeaderSearchOpts, PPOpts,
149                                CodeGenOpts, C, CoverageInfo)),
150          LinkModules(std::move(LinkModules)) {
151      FrontendTimesIsEnabled = TimePasses;
152      llvm::TimePassesIsEnabled = TimePasses;
153    }
154
155    // This constructor is used in installing an empty BackendConsumer
156    // to use the clang diagnostic handler for IR input files. It avoids
157    // initializing the OS field.
158    BackendConsumer(BackendAction Action, DiagnosticsEngine &Diags,
159                    const HeaderSearchOptions &HeaderSearchOpts,
160                    const PreprocessorOptions &PPOpts,
161                    const CodeGenOptions &CodeGenOpts,
162                    const TargetOptions &TargetOpts,
163                    const LangOptions &LangOpts, bool TimePasses,
164                    SmallVector<LinkModule, 4> LinkModules, LLVMContext &C,
165                    CoverageSourceInfo *CoverageInfo = nullptr)
166        : Diags(Diags), Action(Action), HeaderSearchOpts(HeaderSearchOpts),
167          CodeGenOpts(CodeGenOpts), TargetOpts(TargetOpts), LangOpts(LangOpts),
168          Context(nullptr),
169          LLVMIRGeneration("irgen", "LLVM IR Generation Time"),
170          LLVMIRGenerationRefCount(0),
171          Gen(CreateLLVMCodeGen(Diags, "", HeaderSearchOpts, PPOpts,
172                                CodeGenOpts, C, CoverageInfo)),
173          LinkModules(std::move(LinkModules)) {
174      FrontendTimesIsEnabled = TimePasses;
175      llvm::TimePassesIsEnabled = TimePasses;
176    }
177    llvm::Module *getModule() const { return Gen->GetModule(); }
178    std::unique_ptr<llvm::Module> takeModule() {
179      return std::unique_ptr<llvm::Module>(Gen->ReleaseModule());
180    }
181
182    CodeGenerator *getCodeGenerator() { return Gen.get(); }
183
184    void HandleCXXStaticMemberVarInstantiation(VarDecl *VD) override {
185      Gen->HandleCXXStaticMemberVarInstantiation(VD);
186    }
187
188    void Initialize(ASTContext &Ctx) override {
189      assert(!Context && "initialized multiple times");
190
191      Context = &Ctx;
192
193      if (FrontendTimesIsEnabled)
194        LLVMIRGeneration.startTimer();
195
196      Gen->Initialize(Ctx);
197
198      if (FrontendTimesIsEnabled)
199        LLVMIRGeneration.stopTimer();
200    }
201
202    bool HandleTopLevelDecl(DeclGroupRef D) override {
203      PrettyStackTraceDecl CrashInfo(*D.begin(), SourceLocation(),
204                                     Context->getSourceManager(),
205                                     "LLVM IR generation of declaration");
206
207      // Recurse.
208      if (FrontendTimesIsEnabled) {
209        LLVMIRGenerationRefCount += 1;
210        if (LLVMIRGenerationRefCount == 1)
211          LLVMIRGeneration.startTimer();
212      }
213
214      Gen->HandleTopLevelDecl(D);
215
216      if (FrontendTimesIsEnabled) {
217        LLVMIRGenerationRefCount -= 1;
218        if (LLVMIRGenerationRefCount == 0)
219          LLVMIRGeneration.stopTimer();
220      }
221
222      return true;
223    }
224
225    void HandleInlineFunctionDefinition(FunctionDecl *D) override {
226      PrettyStackTraceDecl CrashInfo(D, SourceLocation(),
227                                     Context->getSourceManager(),
228                                     "LLVM IR generation of inline function");
229      if (FrontendTimesIsEnabled)
230        LLVMIRGeneration.startTimer();
231
232      Gen->HandleInlineFunctionDefinition(D);
233
234      if (FrontendTimesIsEnabled)
235        LLVMIRGeneration.stopTimer();
236    }
237
238    void HandleInterestingDecl(DeclGroupRef D) override {
239      // Ignore interesting decls from the AST reader after IRGen is finished.
240      if (!IRGenFinished)
241        HandleTopLevelDecl(D);
242    }
243
244    // Links each entry in LinkModules into our module.  Returns true on error.
245    bool LinkInModules() {
246      for (auto &LM : LinkModules) {
247        if (LM.PropagateAttrs)
248          for (Function &F : *LM.Module)
249            Gen->CGM().addDefaultFunctionDefinitionAttributes(F);
250
251        CurLinkModule = LM.Module.get();
252
253        bool Err;
254        if (LM.Internalize) {
255          Err = Linker::linkModules(
256              *getModule(), std::move(LM.Module), LM.LinkFlags,
257              [](llvm::Module &M, const llvm::StringSet<> &GVS) {
258                internalizeModule(M, [&GVS](const llvm::GlobalValue &GV) {
259                  return !GV.hasName() || (GVS.count(GV.getName()) == 0);
260                });
261              });
262        } else {
263          Err = Linker::linkModules(*getModule(), std::move(LM.Module),
264                                    LM.LinkFlags);
265        }
266
267        if (Err)
268          return true;
269      }
270      return false; // success
271    }
272
273    void HandleTranslationUnit(ASTContext &C) override {
274      {
275        llvm::TimeTraceScope TimeScope("Frontend");
276        PrettyStackTraceString CrashInfo("Per-file LLVM IR generation");
277        if (FrontendTimesIsEnabled) {
278          LLVMIRGenerationRefCount += 1;
279          if (LLVMIRGenerationRefCount == 1)
280            LLVMIRGeneration.startTimer();
281        }
282
283        Gen->HandleTranslationUnit(C);
284
285        if (FrontendTimesIsEnabled) {
286          LLVMIRGenerationRefCount -= 1;
287          if (LLVMIRGenerationRefCount == 0)
288            LLVMIRGeneration.stopTimer();
289        }
290
291        IRGenFinished = true;
292      }
293
294      // Silently ignore if we weren't initialized for some reason.
295      if (!getModule())
296        return;
297
298      // Install an inline asm handler so that diagnostics get printed through
299      // our diagnostics hooks.
300      LLVMContext &Ctx = getModule()->getContext();
301      LLVMContext::InlineAsmDiagHandlerTy OldHandler =
302        Ctx.getInlineAsmDiagnosticHandler();
303      void *OldContext = Ctx.getInlineAsmDiagnosticContext();
304      Ctx.setInlineAsmDiagnosticHandler(InlineAsmDiagHandler, this);
305
306      std::unique_ptr<DiagnosticHandler> OldDiagnosticHandler =
307          Ctx.getDiagnosticHandler();
308      Ctx.setDiagnosticHandler(std::make_unique<ClangDiagnosticHandler>(
309        CodeGenOpts, this));
310
311      Expected<std::unique_ptr<llvm::ToolOutputFile>> OptRecordFileOrErr =
312          setupLLVMOptimizationRemarks(
313              Ctx, CodeGenOpts.OptRecordFile, CodeGenOpts.OptRecordPasses,
314              CodeGenOpts.OptRecordFormat, CodeGenOpts.DiagnosticsWithHotness,
315              CodeGenOpts.DiagnosticsHotnessThreshold);
316
317      if (Error E = OptRecordFileOrErr.takeError()) {
318        reportOptRecordError(std::move(E), Diags, CodeGenOpts);
319        return;
320      }
321
322      std::unique_ptr<llvm::ToolOutputFile> OptRecordFile =
323          std::move(*OptRecordFileOrErr);
324
325      if (OptRecordFile &&
326          CodeGenOpts.getProfileUse() != CodeGenOptions::ProfileNone)
327        Ctx.setDiagnosticsHotnessRequested(true);
328
329      // Link each LinkModule into our module.
330      if (LinkInModules())
331        return;
332
333      EmbedBitcode(getModule(), CodeGenOpts, llvm::MemoryBufferRef());
334
335      EmitBackendOutput(Diags, HeaderSearchOpts, CodeGenOpts, TargetOpts,
336                        LangOpts, C.getTargetInfo().getDataLayout(),
337                        getModule(), Action, std::move(AsmOutStream));
338
339      Ctx.setInlineAsmDiagnosticHandler(OldHandler, OldContext);
340
341      Ctx.setDiagnosticHandler(std::move(OldDiagnosticHandler));
342
343      if (OptRecordFile)
344        OptRecordFile->keep();
345    }
346
347    void HandleTagDeclDefinition(TagDecl *D) override {
348      PrettyStackTraceDecl CrashInfo(D, SourceLocation(),
349                                     Context->getSourceManager(),
350                                     "LLVM IR generation of declaration");
351      Gen->HandleTagDeclDefinition(D);
352    }
353
354    void HandleTagDeclRequiredDefinition(const TagDecl *D) override {
355      Gen->HandleTagDeclRequiredDefinition(D);
356    }
357
358    void CompleteTentativeDefinition(VarDecl *D) override {
359      Gen->CompleteTentativeDefinition(D);
360    }
361
362    void CompleteExternalDeclaration(VarDecl *D) override {
363      Gen->CompleteExternalDeclaration(D);
364    }
365
366    void AssignInheritanceModel(CXXRecordDecl *RD) override {
367      Gen->AssignInheritanceModel(RD);
368    }
369
370    void HandleVTable(CXXRecordDecl *RD) override {
371      Gen->HandleVTable(RD);
372    }
373
374    static void InlineAsmDiagHandler(const llvm::SMDiagnostic &SM,void *Context,
375                                     unsigned LocCookie) {
376      SourceLocation Loc = SourceLocation::getFromRawEncoding(LocCookie);
377      ((BackendConsumer*)Context)->InlineAsmDiagHandler2(SM, Loc);
378    }
379
380    /// Get the best possible source location to represent a diagnostic that
381    /// may have associated debug info.
382    const FullSourceLoc
383    getBestLocationFromDebugLoc(const llvm::DiagnosticInfoWithLocationBase &D,
384                                bool &BadDebugInfo, StringRef &Filename,
385                                unsigned &Line, unsigned &Column) const;
386
387    void InlineAsmDiagHandler2(const llvm::SMDiagnostic &,
388                               SourceLocation LocCookie);
389
390    void DiagnosticHandlerImpl(const llvm::DiagnosticInfo &DI);
391    /// Specialized handler for InlineAsm diagnostic.
392    /// \return True if the diagnostic has been successfully reported, false
393    /// otherwise.
394    bool InlineAsmDiagHandler(const llvm::DiagnosticInfoInlineAsm &D);
395    /// Specialized handler for StackSize diagnostic.
396    /// \return True if the diagnostic has been successfully reported, false
397    /// otherwise.
398    bool StackSizeDiagHandler(const llvm::DiagnosticInfoStackSize &D);
399    /// Specialized handler for unsupported backend feature diagnostic.
400    void UnsupportedDiagHandler(const llvm::DiagnosticInfoUnsupported &D);
401    /// Specialized handler for misexpect warnings.
402    /// Note that misexpect remarks are emitted through ORE
403    void MisExpectDiagHandler(const llvm::DiagnosticInfoMisExpect &D);
404    /// Specialized handlers for optimization remarks.
405    /// Note that these handlers only accept remarks and they always handle
406    /// them.
407    void EmitOptimizationMessage(const llvm::DiagnosticInfoOptimizationBase &D,
408                                 unsigned DiagID);
409    void
410    OptimizationRemarkHandler(const llvm::DiagnosticInfoOptimizationBase &D);
411    void OptimizationRemarkHandler(
412        const llvm::OptimizationRemarkAnalysisFPCommute &D);
413    void OptimizationRemarkHandler(
414        const llvm::OptimizationRemarkAnalysisAliasing &D);
415    void OptimizationFailureHandler(
416        const llvm::DiagnosticInfoOptimizationFailure &D);
417  };
418
419  void BackendConsumer::anchor() {}
420}
421
422bool ClangDiagnosticHandler::handleDiagnostics(const DiagnosticInfo &DI) {
423  BackendCon->DiagnosticHandlerImpl(DI);
424  return true;
425}
426
427/// ConvertBackendLocation - Convert a location in a temporary llvm::SourceMgr
428/// buffer to be a valid FullSourceLoc.
429static FullSourceLoc ConvertBackendLocation(const llvm::SMDiagnostic &D,
430                                            SourceManager &CSM) {
431  // Get both the clang and llvm source managers.  The location is relative to
432  // a memory buffer that the LLVM Source Manager is handling, we need to add
433  // a copy to the Clang source manager.
434  const llvm::SourceMgr &LSM = *D.getSourceMgr();
435
436  // We need to copy the underlying LLVM memory buffer because llvm::SourceMgr
437  // already owns its one and clang::SourceManager wants to own its one.
438  const MemoryBuffer *LBuf =
439  LSM.getMemoryBuffer(LSM.FindBufferContainingLoc(D.getLoc()));
440
441  // Create the copy and transfer ownership to clang::SourceManager.
442  // TODO: Avoid copying files into memory.
443  std::unique_ptr<llvm::MemoryBuffer> CBuf =
444      llvm::MemoryBuffer::getMemBufferCopy(LBuf->getBuffer(),
445                                           LBuf->getBufferIdentifier());
446  // FIXME: Keep a file ID map instead of creating new IDs for each location.
447  FileID FID = CSM.createFileID(std::move(CBuf));
448
449  // Translate the offset into the file.
450  unsigned Offset = D.getLoc().getPointer() - LBuf->getBufferStart();
451  SourceLocation NewLoc =
452  CSM.getLocForStartOfFile(FID).getLocWithOffset(Offset);
453  return FullSourceLoc(NewLoc, CSM);
454}
455
456
457/// InlineAsmDiagHandler2 - This function is invoked when the backend hits an
458/// error parsing inline asm.  The SMDiagnostic indicates the error relative to
459/// the temporary memory buffer that the inline asm parser has set up.
460void BackendConsumer::InlineAsmDiagHandler2(const llvm::SMDiagnostic &D,
461                                            SourceLocation LocCookie) {
462  // There are a couple of different kinds of errors we could get here.  First,
463  // we re-format the SMDiagnostic in terms of a clang diagnostic.
464
465  // Strip "error: " off the start of the message string.
466  StringRef Message = D.getMessage();
467  if (Message.startswith("error: "))
468    Message = Message.substr(7);
469
470  // If the SMDiagnostic has an inline asm source location, translate it.
471  FullSourceLoc Loc;
472  if (D.getLoc() != SMLoc())
473    Loc = ConvertBackendLocation(D, Context->getSourceManager());
474
475  unsigned DiagID;
476  switch (D.getKind()) {
477  case llvm::SourceMgr::DK_Error:
478    DiagID = diag::err_fe_inline_asm;
479    break;
480  case llvm::SourceMgr::DK_Warning:
481    DiagID = diag::warn_fe_inline_asm;
482    break;
483  case llvm::SourceMgr::DK_Note:
484    DiagID = diag::note_fe_inline_asm;
485    break;
486  case llvm::SourceMgr::DK_Remark:
487    llvm_unreachable("remarks unexpected");
488  }
489  // If this problem has clang-level source location information, report the
490  // issue in the source with a note showing the instantiated
491  // code.
492  if (LocCookie.isValid()) {
493    Diags.Report(LocCookie, DiagID).AddString(Message);
494
495    if (D.getLoc().isValid()) {
496      DiagnosticBuilder B = Diags.Report(Loc, diag::note_fe_inline_asm_here);
497      // Convert the SMDiagnostic ranges into SourceRange and attach them
498      // to the diagnostic.
499      for (const std::pair<unsigned, unsigned> &Range : D.getRanges()) {
500        unsigned Column = D.getColumnNo();
501        B << SourceRange(Loc.getLocWithOffset(Range.first - Column),
502                         Loc.getLocWithOffset(Range.second - Column));
503      }
504    }
505    return;
506  }
507
508  // Otherwise, report the backend issue as occurring in the generated .s file.
509  // If Loc is invalid, we still need to report the issue, it just gets no
510  // location info.
511  Diags.Report(Loc, DiagID).AddString(Message);
512}
513
514#define ComputeDiagID(Severity, GroupName, DiagID)                             \
515  do {                                                                         \
516    switch (Severity) {                                                        \
517    case llvm::DS_Error:                                                       \
518      DiagID = diag::err_fe_##GroupName;                                       \
519      break;                                                                   \
520    case llvm::DS_Warning:                                                     \
521      DiagID = diag::warn_fe_##GroupName;                                      \
522      break;                                                                   \
523    case llvm::DS_Remark:                                                      \
524      llvm_unreachable("'remark' severity not expected");                      \
525      break;                                                                   \
526    case llvm::DS_Note:                                                        \
527      DiagID = diag::note_fe_##GroupName;                                      \
528      break;                                                                   \
529    }                                                                          \
530  } while (false)
531
532#define ComputeDiagRemarkID(Severity, GroupName, DiagID)                       \
533  do {                                                                         \
534    switch (Severity) {                                                        \
535    case llvm::DS_Error:                                                       \
536      DiagID = diag::err_fe_##GroupName;                                       \
537      break;                                                                   \
538    case llvm::DS_Warning:                                                     \
539      DiagID = diag::warn_fe_##GroupName;                                      \
540      break;                                                                   \
541    case llvm::DS_Remark:                                                      \
542      DiagID = diag::remark_fe_##GroupName;                                    \
543      break;                                                                   \
544    case llvm::DS_Note:                                                        \
545      DiagID = diag::note_fe_##GroupName;                                      \
546      break;                                                                   \
547    }                                                                          \
548  } while (false)
549
550bool
551BackendConsumer::InlineAsmDiagHandler(const llvm::DiagnosticInfoInlineAsm &D) {
552  unsigned DiagID;
553  ComputeDiagID(D.getSeverity(), inline_asm, DiagID);
554  std::string Message = D.getMsgStr().str();
555
556  // If this problem has clang-level source location information, report the
557  // issue as being a problem in the source with a note showing the instantiated
558  // code.
559  SourceLocation LocCookie =
560      SourceLocation::getFromRawEncoding(D.getLocCookie());
561  if (LocCookie.isValid())
562    Diags.Report(LocCookie, DiagID).AddString(Message);
563  else {
564    // Otherwise, report the backend diagnostic as occurring in the generated
565    // .s file.
566    // If Loc is invalid, we still need to report the diagnostic, it just gets
567    // no location info.
568    FullSourceLoc Loc;
569    Diags.Report(Loc, DiagID).AddString(Message);
570  }
571  // We handled all the possible severities.
572  return true;
573}
574
575bool
576BackendConsumer::StackSizeDiagHandler(const llvm::DiagnosticInfoStackSize &D) {
577  if (D.getSeverity() != llvm::DS_Warning)
578    // For now, the only support we have for StackSize diagnostic is warning.
579    // We do not know how to format other severities.
580    return false;
581
582  if (const Decl *ND = Gen->GetDeclForMangledName(D.getFunction().getName())) {
583    // FIXME: Shouldn't need to truncate to uint32_t
584    Diags.Report(ND->getASTContext().getFullLoc(ND->getLocation()),
585                 diag::warn_fe_frame_larger_than)
586      << static_cast<uint32_t>(D.getStackSize()) << Decl::castToDeclContext(ND);
587    return true;
588  }
589
590  return false;
591}
592
593const FullSourceLoc BackendConsumer::getBestLocationFromDebugLoc(
594    const llvm::DiagnosticInfoWithLocationBase &D, bool &BadDebugInfo,
595    StringRef &Filename, unsigned &Line, unsigned &Column) const {
596  SourceManager &SourceMgr = Context->getSourceManager();
597  FileManager &FileMgr = SourceMgr.getFileManager();
598  SourceLocation DILoc;
599
600  if (D.isLocationAvailable()) {
601    D.getLocation(Filename, Line, Column);
602    if (Line > 0) {
603      auto FE = FileMgr.getFile(Filename);
604      if (!FE)
605        FE = FileMgr.getFile(D.getAbsolutePath());
606      if (FE) {
607        // If -gcolumn-info was not used, Column will be 0. This upsets the
608        // source manager, so pass 1 if Column is not set.
609        DILoc = SourceMgr.translateFileLineCol(*FE, Line, Column ? Column : 1);
610      }
611    }
612    BadDebugInfo = DILoc.isInvalid();
613  }
614
615  // If a location isn't available, try to approximate it using the associated
616  // function definition. We use the definition's right brace to differentiate
617  // from diagnostics that genuinely relate to the function itself.
618  FullSourceLoc Loc(DILoc, SourceMgr);
619  if (Loc.isInvalid())
620    if (const Decl *FD = Gen->GetDeclForMangledName(D.getFunction().getName()))
621      Loc = FD->getASTContext().getFullLoc(FD->getLocation());
622
623  if (DILoc.isInvalid() && D.isLocationAvailable())
624    // If we were not able to translate the file:line:col information
625    // back to a SourceLocation, at least emit a note stating that
626    // we could not translate this location. This can happen in the
627    // case of #line directives.
628    Diags.Report(Loc, diag::note_fe_backend_invalid_loc)
629        << Filename << Line << Column;
630
631  return Loc;
632}
633
634void BackendConsumer::UnsupportedDiagHandler(
635    const llvm::DiagnosticInfoUnsupported &D) {
636  // We only support warnings or errors.
637  assert(D.getSeverity() == llvm::DS_Error ||
638         D.getSeverity() == llvm::DS_Warning);
639
640  StringRef Filename;
641  unsigned Line, Column;
642  bool BadDebugInfo = false;
643  FullSourceLoc Loc;
644  std::string Msg;
645  raw_string_ostream MsgStream(Msg);
646
647  // Context will be nullptr for IR input files, we will construct the diag
648  // message from llvm::DiagnosticInfoUnsupported.
649  if (Context != nullptr) {
650    Loc = getBestLocationFromDebugLoc(D, BadDebugInfo, Filename, Line, Column);
651    MsgStream << D.getMessage();
652  } else {
653    DiagnosticPrinterRawOStream DP(MsgStream);
654    D.print(DP);
655  }
656
657  auto DiagType = D.getSeverity() == llvm::DS_Error
658                      ? diag::err_fe_backend_unsupported
659                      : diag::warn_fe_backend_unsupported;
660  Diags.Report(Loc, DiagType) << MsgStream.str();
661
662  if (BadDebugInfo)
663    // If we were not able to translate the file:line:col information
664    // back to a SourceLocation, at least emit a note stating that
665    // we could not translate this location. This can happen in the
666    // case of #line directives.
667    Diags.Report(Loc, diag::note_fe_backend_invalid_loc)
668        << Filename << Line << Column;
669}
670
671void BackendConsumer::MisExpectDiagHandler(
672    const llvm::DiagnosticInfoMisExpect &D) {
673  StringRef Filename;
674  unsigned Line, Column;
675  bool BadDebugInfo = false;
676  FullSourceLoc Loc;
677  std::string Msg;
678  raw_string_ostream MsgStream(Msg);
679  DiagnosticPrinterRawOStream DP(MsgStream);
680
681  // Context will be nullptr for IR input files, we will construct the diag
682  // message from llvm::DiagnosticInfoMisExpect.
683  if (Context != nullptr) {
684    Loc = getBestLocationFromDebugLoc(D, BadDebugInfo, Filename, Line, Column);
685    MsgStream << D.getMsg();
686  } else {
687    DiagnosticPrinterRawOStream DP(MsgStream);
688    D.print(DP);
689  }
690  Diags.Report(Loc, diag::warn_profile_data_misexpect) << MsgStream.str();
691
692  if (BadDebugInfo)
693    // If we were not able to translate the file:line:col information
694    // back to a SourceLocation, at least emit a note stating that
695    // we could not translate this location. This can happen in the
696    // case of #line directives.
697    Diags.Report(Loc, diag::note_fe_backend_invalid_loc)
698        << Filename << Line << Column;
699}
700
701void BackendConsumer::EmitOptimizationMessage(
702    const llvm::DiagnosticInfoOptimizationBase &D, unsigned DiagID) {
703  // We only support warnings and remarks.
704  assert(D.getSeverity() == llvm::DS_Remark ||
705         D.getSeverity() == llvm::DS_Warning);
706
707  StringRef Filename;
708  unsigned Line, Column;
709  bool BadDebugInfo = false;
710  FullSourceLoc Loc;
711  std::string Msg;
712  raw_string_ostream MsgStream(Msg);
713
714  // Context will be nullptr for IR input files, we will construct the remark
715  // message from llvm::DiagnosticInfoOptimizationBase.
716  if (Context != nullptr) {
717    Loc = getBestLocationFromDebugLoc(D, BadDebugInfo, Filename, Line, Column);
718    MsgStream << D.getMsg();
719  } else {
720    DiagnosticPrinterRawOStream DP(MsgStream);
721    D.print(DP);
722  }
723
724  if (D.getHotness())
725    MsgStream << " (hotness: " << *D.getHotness() << ")";
726
727  Diags.Report(Loc, DiagID)
728      << AddFlagValue(D.getPassName())
729      << MsgStream.str();
730
731  if (BadDebugInfo)
732    // If we were not able to translate the file:line:col information
733    // back to a SourceLocation, at least emit a note stating that
734    // we could not translate this location. This can happen in the
735    // case of #line directives.
736    Diags.Report(Loc, diag::note_fe_backend_invalid_loc)
737        << Filename << Line << Column;
738}
739
740void BackendConsumer::OptimizationRemarkHandler(
741    const llvm::DiagnosticInfoOptimizationBase &D) {
742  // Without hotness information, don't show noisy remarks.
743  if (D.isVerbose() && !D.getHotness())
744    return;
745
746  if (D.isPassed()) {
747    // Optimization remarks are active only if the -Rpass flag has a regular
748    // expression that matches the name of the pass name in \p D.
749    if (CodeGenOpts.OptimizationRemarkPattern &&
750        CodeGenOpts.OptimizationRemarkPattern->match(D.getPassName()))
751      EmitOptimizationMessage(D, diag::remark_fe_backend_optimization_remark);
752  } else if (D.isMissed()) {
753    // Missed optimization remarks are active only if the -Rpass-missed
754    // flag has a regular expression that matches the name of the pass
755    // name in \p D.
756    if (CodeGenOpts.OptimizationRemarkMissedPattern &&
757        CodeGenOpts.OptimizationRemarkMissedPattern->match(D.getPassName()))
758      EmitOptimizationMessage(
759          D, diag::remark_fe_backend_optimization_remark_missed);
760  } else {
761    assert(D.isAnalysis() && "Unknown remark type");
762
763    bool ShouldAlwaysPrint = false;
764    if (auto *ORA = dyn_cast<llvm::OptimizationRemarkAnalysis>(&D))
765      ShouldAlwaysPrint = ORA->shouldAlwaysPrint();
766
767    if (ShouldAlwaysPrint ||
768        (CodeGenOpts.OptimizationRemarkAnalysisPattern &&
769         CodeGenOpts.OptimizationRemarkAnalysisPattern->match(D.getPassName())))
770      EmitOptimizationMessage(
771          D, diag::remark_fe_backend_optimization_remark_analysis);
772  }
773}
774
775void BackendConsumer::OptimizationRemarkHandler(
776    const llvm::OptimizationRemarkAnalysisFPCommute &D) {
777  // Optimization analysis remarks are active if the pass name is set to
778  // llvm::DiagnosticInfo::AlwasyPrint or if the -Rpass-analysis flag has a
779  // regular expression that matches the name of the pass name in \p D.
780
781  if (D.shouldAlwaysPrint() ||
782      (CodeGenOpts.OptimizationRemarkAnalysisPattern &&
783       CodeGenOpts.OptimizationRemarkAnalysisPattern->match(D.getPassName())))
784    EmitOptimizationMessage(
785        D, diag::remark_fe_backend_optimization_remark_analysis_fpcommute);
786}
787
788void BackendConsumer::OptimizationRemarkHandler(
789    const llvm::OptimizationRemarkAnalysisAliasing &D) {
790  // Optimization analysis remarks are active if the pass name is set to
791  // llvm::DiagnosticInfo::AlwasyPrint or if the -Rpass-analysis flag has a
792  // regular expression that matches the name of the pass name in \p D.
793
794  if (D.shouldAlwaysPrint() ||
795      (CodeGenOpts.OptimizationRemarkAnalysisPattern &&
796       CodeGenOpts.OptimizationRemarkAnalysisPattern->match(D.getPassName())))
797    EmitOptimizationMessage(
798        D, diag::remark_fe_backend_optimization_remark_analysis_aliasing);
799}
800
801void BackendConsumer::OptimizationFailureHandler(
802    const llvm::DiagnosticInfoOptimizationFailure &D) {
803  EmitOptimizationMessage(D, diag::warn_fe_backend_optimization_failure);
804}
805
806/// This function is invoked when the backend needs
807/// to report something to the user.
808void BackendConsumer::DiagnosticHandlerImpl(const DiagnosticInfo &DI) {
809  unsigned DiagID = diag::err_fe_inline_asm;
810  llvm::DiagnosticSeverity Severity = DI.getSeverity();
811  // Get the diagnostic ID based.
812  switch (DI.getKind()) {
813  case llvm::DK_InlineAsm:
814    if (InlineAsmDiagHandler(cast<DiagnosticInfoInlineAsm>(DI)))
815      return;
816    ComputeDiagID(Severity, inline_asm, DiagID);
817    break;
818  case llvm::DK_StackSize:
819    if (StackSizeDiagHandler(cast<DiagnosticInfoStackSize>(DI)))
820      return;
821    ComputeDiagID(Severity, backend_frame_larger_than, DiagID);
822    break;
823  case DK_Linker:
824    assert(CurLinkModule);
825    // FIXME: stop eating the warnings and notes.
826    if (Severity != DS_Error)
827      return;
828    DiagID = diag::err_fe_cannot_link_module;
829    break;
830  case llvm::DK_OptimizationRemark:
831    // Optimization remarks are always handled completely by this
832    // handler. There is no generic way of emitting them.
833    OptimizationRemarkHandler(cast<OptimizationRemark>(DI));
834    return;
835  case llvm::DK_OptimizationRemarkMissed:
836    // Optimization remarks are always handled completely by this
837    // handler. There is no generic way of emitting them.
838    OptimizationRemarkHandler(cast<OptimizationRemarkMissed>(DI));
839    return;
840  case llvm::DK_OptimizationRemarkAnalysis:
841    // Optimization remarks are always handled completely by this
842    // handler. There is no generic way of emitting them.
843    OptimizationRemarkHandler(cast<OptimizationRemarkAnalysis>(DI));
844    return;
845  case llvm::DK_OptimizationRemarkAnalysisFPCommute:
846    // Optimization remarks are always handled completely by this
847    // handler. There is no generic way of emitting them.
848    OptimizationRemarkHandler(cast<OptimizationRemarkAnalysisFPCommute>(DI));
849    return;
850  case llvm::DK_OptimizationRemarkAnalysisAliasing:
851    // Optimization remarks are always handled completely by this
852    // handler. There is no generic way of emitting them.
853    OptimizationRemarkHandler(cast<OptimizationRemarkAnalysisAliasing>(DI));
854    return;
855  case llvm::DK_MachineOptimizationRemark:
856    // Optimization remarks are always handled completely by this
857    // handler. There is no generic way of emitting them.
858    OptimizationRemarkHandler(cast<MachineOptimizationRemark>(DI));
859    return;
860  case llvm::DK_MachineOptimizationRemarkMissed:
861    // Optimization remarks are always handled completely by this
862    // handler. There is no generic way of emitting them.
863    OptimizationRemarkHandler(cast<MachineOptimizationRemarkMissed>(DI));
864    return;
865  case llvm::DK_MachineOptimizationRemarkAnalysis:
866    // Optimization remarks are always handled completely by this
867    // handler. There is no generic way of emitting them.
868    OptimizationRemarkHandler(cast<MachineOptimizationRemarkAnalysis>(DI));
869    return;
870  case llvm::DK_OptimizationFailure:
871    // Optimization failures are always handled completely by this
872    // handler.
873    OptimizationFailureHandler(cast<DiagnosticInfoOptimizationFailure>(DI));
874    return;
875  case llvm::DK_Unsupported:
876    UnsupportedDiagHandler(cast<DiagnosticInfoUnsupported>(DI));
877    return;
878  case llvm::DK_MisExpect:
879    MisExpectDiagHandler(cast<DiagnosticInfoMisExpect>(DI));
880    return;
881  default:
882    // Plugin IDs are not bound to any value as they are set dynamically.
883    ComputeDiagRemarkID(Severity, backend_plugin, DiagID);
884    break;
885  }
886  std::string MsgStorage;
887  {
888    raw_string_ostream Stream(MsgStorage);
889    DiagnosticPrinterRawOStream DP(Stream);
890    DI.print(DP);
891  }
892
893  if (DiagID == diag::err_fe_cannot_link_module) {
894    Diags.Report(diag::err_fe_cannot_link_module)
895        << CurLinkModule->getModuleIdentifier() << MsgStorage;
896    return;
897  }
898
899  // Report the backend message using the usual diagnostic mechanism.
900  FullSourceLoc Loc;
901  Diags.Report(Loc, DiagID).AddString(MsgStorage);
902}
903#undef ComputeDiagID
904
905CodeGenAction::CodeGenAction(unsigned _Act, LLVMContext *_VMContext)
906    : Act(_Act), VMContext(_VMContext ? _VMContext : new LLVMContext),
907      OwnsVMContext(!_VMContext) {}
908
909CodeGenAction::~CodeGenAction() {
910  TheModule.reset();
911  if (OwnsVMContext)
912    delete VMContext;
913}
914
915bool CodeGenAction::hasIRSupport() const { return true; }
916
917void CodeGenAction::EndSourceFileAction() {
918  // If the consumer creation failed, do nothing.
919  if (!getCompilerInstance().hasASTConsumer())
920    return;
921
922  // Steal the module from the consumer.
923  TheModule = BEConsumer->takeModule();
924}
925
926std::unique_ptr<llvm::Module> CodeGenAction::takeModule() {
927  return std::move(TheModule);
928}
929
930llvm::LLVMContext *CodeGenAction::takeLLVMContext() {
931  OwnsVMContext = false;
932  return VMContext;
933}
934
935static std::unique_ptr<raw_pwrite_stream>
936GetOutputStream(CompilerInstance &CI, StringRef InFile, BackendAction Action) {
937  switch (Action) {
938  case Backend_EmitAssembly:
939    return CI.createDefaultOutputFile(false, InFile, "s");
940  case Backend_EmitLL:
941    return CI.createDefaultOutputFile(false, InFile, "ll");
942  case Backend_EmitBC:
943    return CI.createDefaultOutputFile(true, InFile, "bc");
944  case Backend_EmitNothing:
945    return nullptr;
946  case Backend_EmitMCNull:
947    return CI.createNullOutputFile();
948  case Backend_EmitObj:
949    return CI.createDefaultOutputFile(true, InFile, "o");
950  }
951
952  llvm_unreachable("Invalid action!");
953}
954
955std::unique_ptr<ASTConsumer>
956CodeGenAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
957  BackendAction BA = static_cast<BackendAction>(Act);
958  std::unique_ptr<raw_pwrite_stream> OS = CI.takeOutputStream();
959  if (!OS)
960    OS = GetOutputStream(CI, InFile, BA);
961
962  if (BA != Backend_EmitNothing && !OS)
963    return nullptr;
964
965  // Load bitcode modules to link with, if we need to.
966  if (LinkModules.empty())
967    for (const CodeGenOptions::BitcodeFileToLink &F :
968         CI.getCodeGenOpts().LinkBitcodeFiles) {
969      auto BCBuf = CI.getFileManager().getBufferForFile(F.Filename);
970      if (!BCBuf) {
971        CI.getDiagnostics().Report(diag::err_cannot_open_file)
972            << F.Filename << BCBuf.getError().message();
973        LinkModules.clear();
974        return nullptr;
975      }
976
977      Expected<std::unique_ptr<llvm::Module>> ModuleOrErr =
978          getOwningLazyBitcodeModule(std::move(*BCBuf), *VMContext);
979      if (!ModuleOrErr) {
980        handleAllErrors(ModuleOrErr.takeError(), [&](ErrorInfoBase &EIB) {
981          CI.getDiagnostics().Report(diag::err_cannot_open_file)
982              << F.Filename << EIB.message();
983        });
984        LinkModules.clear();
985        return nullptr;
986      }
987      LinkModules.push_back({std::move(ModuleOrErr.get()), F.PropagateAttrs,
988                             F.Internalize, F.LinkFlags});
989    }
990
991  CoverageSourceInfo *CoverageInfo = nullptr;
992  // Add the preprocessor callback only when the coverage mapping is generated.
993  if (CI.getCodeGenOpts().CoverageMapping) {
994    CoverageInfo = new CoverageSourceInfo;
995    CI.getPreprocessor().addPPCallbacks(
996                                    std::unique_ptr<PPCallbacks>(CoverageInfo));
997  }
998
999  std::unique_ptr<BackendConsumer> Result(new BackendConsumer(
1000      BA, CI.getDiagnostics(), CI.getHeaderSearchOpts(),
1001      CI.getPreprocessorOpts(), CI.getCodeGenOpts(), CI.getTargetOpts(),
1002      CI.getLangOpts(), CI.getFrontendOpts().ShowTimers, std::string(InFile),
1003      std::move(LinkModules), std::move(OS), *VMContext, CoverageInfo));
1004  BEConsumer = Result.get();
1005
1006  // Enable generating macro debug info only when debug info is not disabled and
1007  // also macro debug info is enabled.
1008  if (CI.getCodeGenOpts().getDebugInfo() != codegenoptions::NoDebugInfo &&
1009      CI.getCodeGenOpts().MacroDebugInfo) {
1010    std::unique_ptr<PPCallbacks> Callbacks =
1011        std::make_unique<MacroPPCallbacks>(BEConsumer->getCodeGenerator(),
1012                                            CI.getPreprocessor());
1013    CI.getPreprocessor().addPPCallbacks(std::move(Callbacks));
1014  }
1015
1016  return std::move(Result);
1017}
1018
1019static void BitcodeInlineAsmDiagHandler(const llvm::SMDiagnostic &SM,
1020                                         void *Context,
1021                                         unsigned LocCookie) {
1022  SM.print(nullptr, llvm::errs());
1023
1024  auto Diags = static_cast<DiagnosticsEngine *>(Context);
1025  unsigned DiagID;
1026  switch (SM.getKind()) {
1027  case llvm::SourceMgr::DK_Error:
1028    DiagID = diag::err_fe_inline_asm;
1029    break;
1030  case llvm::SourceMgr::DK_Warning:
1031    DiagID = diag::warn_fe_inline_asm;
1032    break;
1033  case llvm::SourceMgr::DK_Note:
1034    DiagID = diag::note_fe_inline_asm;
1035    break;
1036  case llvm::SourceMgr::DK_Remark:
1037    llvm_unreachable("remarks unexpected");
1038  }
1039
1040  Diags->Report(DiagID).AddString("cannot compile inline asm");
1041}
1042
1043std::unique_ptr<llvm::Module>
1044CodeGenAction::loadModule(MemoryBufferRef MBRef) {
1045  CompilerInstance &CI = getCompilerInstance();
1046  SourceManager &SM = CI.getSourceManager();
1047
1048  // For ThinLTO backend invocations, ensure that the context
1049  // merges types based on ODR identifiers. We also need to read
1050  // the correct module out of a multi-module bitcode file.
1051  if (!CI.getCodeGenOpts().ThinLTOIndexFile.empty()) {
1052    VMContext->enableDebugTypeODRUniquing();
1053
1054    auto DiagErrors = [&](Error E) -> std::unique_ptr<llvm::Module> {
1055      unsigned DiagID =
1056          CI.getDiagnostics().getCustomDiagID(DiagnosticsEngine::Error, "%0");
1057      handleAllErrors(std::move(E), [&](ErrorInfoBase &EIB) {
1058        CI.getDiagnostics().Report(DiagID) << EIB.message();
1059      });
1060      return {};
1061    };
1062
1063    Expected<std::vector<BitcodeModule>> BMsOrErr = getBitcodeModuleList(MBRef);
1064    if (!BMsOrErr)
1065      return DiagErrors(BMsOrErr.takeError());
1066    BitcodeModule *Bm = FindThinLTOModule(*BMsOrErr);
1067    // We have nothing to do if the file contains no ThinLTO module. This is
1068    // possible if ThinLTO compilation was not able to split module. Content of
1069    // the file was already processed by indexing and will be passed to the
1070    // linker using merged object file.
1071    if (!Bm) {
1072      auto M = std::make_unique<llvm::Module>("empty", *VMContext);
1073      M->setTargetTriple(CI.getTargetOpts().Triple);
1074      return M;
1075    }
1076    Expected<std::unique_ptr<llvm::Module>> MOrErr =
1077        Bm->parseModule(*VMContext);
1078    if (!MOrErr)
1079      return DiagErrors(MOrErr.takeError());
1080    return std::move(*MOrErr);
1081  }
1082
1083  llvm::SMDiagnostic Err;
1084  if (std::unique_ptr<llvm::Module> M = parseIR(MBRef, Err, *VMContext))
1085    return M;
1086
1087  // Translate from the diagnostic info to the SourceManager location if
1088  // available.
1089  // TODO: Unify this with ConvertBackendLocation()
1090  SourceLocation Loc;
1091  if (Err.getLineNo() > 0) {
1092    assert(Err.getColumnNo() >= 0);
1093    Loc = SM.translateFileLineCol(SM.getFileEntryForID(SM.getMainFileID()),
1094                                  Err.getLineNo(), Err.getColumnNo() + 1);
1095  }
1096
1097  // Strip off a leading diagnostic code if there is one.
1098  StringRef Msg = Err.getMessage();
1099  if (Msg.startswith("error: "))
1100    Msg = Msg.substr(7);
1101
1102  unsigned DiagID =
1103      CI.getDiagnostics().getCustomDiagID(DiagnosticsEngine::Error, "%0");
1104
1105  CI.getDiagnostics().Report(Loc, DiagID) << Msg;
1106  return {};
1107}
1108
1109void CodeGenAction::ExecuteAction() {
1110  // If this is an IR file, we have to treat it specially.
1111  if (getCurrentFileKind().getLanguage() == Language::LLVM_IR) {
1112    BackendAction BA = static_cast<BackendAction>(Act);
1113    CompilerInstance &CI = getCompilerInstance();
1114    auto &CodeGenOpts = CI.getCodeGenOpts();
1115    auto &Diagnostics = CI.getDiagnostics();
1116    std::unique_ptr<raw_pwrite_stream> OS =
1117        GetOutputStream(CI, getCurrentFile(), BA);
1118    if (BA != Backend_EmitNothing && !OS)
1119      return;
1120
1121    bool Invalid;
1122    SourceManager &SM = CI.getSourceManager();
1123    FileID FID = SM.getMainFileID();
1124    const llvm::MemoryBuffer *MainFile = SM.getBuffer(FID, &Invalid);
1125    if (Invalid)
1126      return;
1127
1128    TheModule = loadModule(*MainFile);
1129    if (!TheModule)
1130      return;
1131
1132    const TargetOptions &TargetOpts = CI.getTargetOpts();
1133    if (TheModule->getTargetTriple() != TargetOpts.Triple) {
1134      Diagnostics.Report(SourceLocation(),
1135                         diag::warn_fe_override_module)
1136          << TargetOpts.Triple;
1137      TheModule->setTargetTriple(TargetOpts.Triple);
1138    }
1139
1140    EmbedBitcode(TheModule.get(), CodeGenOpts,
1141                 MainFile->getMemBufferRef());
1142
1143    LLVMContext &Ctx = TheModule->getContext();
1144    Ctx.setInlineAsmDiagnosticHandler(BitcodeInlineAsmDiagHandler,
1145                                      &Diagnostics);
1146
1147    // Set clang diagnostic handler. To do this we need to create a fake
1148    // BackendConsumer.
1149    BackendConsumer Result(BA, CI.getDiagnostics(), CI.getHeaderSearchOpts(),
1150                           CI.getPreprocessorOpts(), CI.getCodeGenOpts(),
1151                           CI.getTargetOpts(), CI.getLangOpts(),
1152                           CI.getFrontendOpts().ShowTimers,
1153                           std::move(LinkModules), *VMContext, nullptr);
1154    // PR44896: Force DiscardValueNames as false. DiscardValueNames cannot be
1155    // true here because the valued names are needed for reading textual IR.
1156    Ctx.setDiscardValueNames(false);
1157    Ctx.setDiagnosticHandler(
1158        std::make_unique<ClangDiagnosticHandler>(CodeGenOpts, &Result));
1159
1160    Expected<std::unique_ptr<llvm::ToolOutputFile>> OptRecordFileOrErr =
1161        setupLLVMOptimizationRemarks(
1162            Ctx, CodeGenOpts.OptRecordFile, CodeGenOpts.OptRecordPasses,
1163            CodeGenOpts.OptRecordFormat, CodeGenOpts.DiagnosticsWithHotness,
1164            CodeGenOpts.DiagnosticsHotnessThreshold);
1165
1166    if (Error E = OptRecordFileOrErr.takeError()) {
1167      reportOptRecordError(std::move(E), Diagnostics, CodeGenOpts);
1168      return;
1169    }
1170    std::unique_ptr<llvm::ToolOutputFile> OptRecordFile =
1171        std::move(*OptRecordFileOrErr);
1172
1173    EmitBackendOutput(Diagnostics, CI.getHeaderSearchOpts(), CodeGenOpts,
1174                      TargetOpts, CI.getLangOpts(),
1175                      CI.getTarget().getDataLayout(), TheModule.get(), BA,
1176                      std::move(OS));
1177
1178    if (OptRecordFile)
1179      OptRecordFile->keep();
1180    return;
1181  }
1182
1183  // Otherwise follow the normal AST path.
1184  this->ASTFrontendAction::ExecuteAction();
1185}
1186
1187//
1188
1189void EmitAssemblyAction::anchor() { }
1190EmitAssemblyAction::EmitAssemblyAction(llvm::LLVMContext *_VMContext)
1191  : CodeGenAction(Backend_EmitAssembly, _VMContext) {}
1192
1193void EmitBCAction::anchor() { }
1194EmitBCAction::EmitBCAction(llvm::LLVMContext *_VMContext)
1195  : CodeGenAction(Backend_EmitBC, _VMContext) {}
1196
1197void EmitLLVMAction::anchor() { }
1198EmitLLVMAction::EmitLLVMAction(llvm::LLVMContext *_VMContext)
1199  : CodeGenAction(Backend_EmitLL, _VMContext) {}
1200
1201void EmitLLVMOnlyAction::anchor() { }
1202EmitLLVMOnlyAction::EmitLLVMOnlyAction(llvm::LLVMContext *_VMContext)
1203  : CodeGenAction(Backend_EmitNothing, _VMContext) {}
1204
1205void EmitCodeGenOnlyAction::anchor() { }
1206EmitCodeGenOnlyAction::EmitCodeGenOnlyAction(llvm::LLVMContext *_VMContext)
1207  : CodeGenAction(Backend_EmitMCNull, _VMContext) {}
1208
1209void EmitObjAction::anchor() { }
1210EmitObjAction::EmitObjAction(llvm::LLVMContext *_VMContext)
1211  : CodeGenAction(Backend_EmitObj, _VMContext) {}
1212