xref: /freebsd/contrib/llvm-project/clang/lib/Frontend/FrontendAction.cpp (revision 47e073941f4e7ca6e9bde3fa65abbfcfed6bfa2b)
1  //===--- FrontendAction.cpp -----------------------------------------------===//
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/Frontend/FrontendAction.h"
10  #include "clang/AST/ASTConsumer.h"
11  #include "clang/AST/ASTContext.h"
12  #include "clang/AST/DeclGroup.h"
13  #include "clang/Basic/Builtins.h"
14  #include "clang/Basic/DiagnosticOptions.h"
15  #include "clang/Basic/FileEntry.h"
16  #include "clang/Basic/LangStandard.h"
17  #include "clang/Basic/Sarif.h"
18  #include "clang/Basic/Stack.h"
19  #include "clang/Frontend/ASTUnit.h"
20  #include "clang/Frontend/CompilerInstance.h"
21  #include "clang/Frontend/FrontendDiagnostic.h"
22  #include "clang/Frontend/FrontendPluginRegistry.h"
23  #include "clang/Frontend/LayoutOverrideSource.h"
24  #include "clang/Frontend/MultiplexConsumer.h"
25  #include "clang/Frontend/SARIFDiagnosticPrinter.h"
26  #include "clang/Frontend/Utils.h"
27  #include "clang/Lex/HeaderSearch.h"
28  #include "clang/Lex/LiteralSupport.h"
29  #include "clang/Lex/Preprocessor.h"
30  #include "clang/Lex/PreprocessorOptions.h"
31  #include "clang/Parse/ParseAST.h"
32  #include "clang/Sema/HLSLExternalSemaSource.h"
33  #include "clang/Sema/MultiplexExternalSemaSource.h"
34  #include "clang/Serialization/ASTDeserializationListener.h"
35  #include "clang/Serialization/ASTReader.h"
36  #include "clang/Serialization/GlobalModuleIndex.h"
37  #include "llvm/ADT/ScopeExit.h"
38  #include "llvm/Support/BuryPointer.h"
39  #include "llvm/Support/ErrorHandling.h"
40  #include "llvm/Support/FileSystem.h"
41  #include "llvm/Support/Path.h"
42  #include "llvm/Support/Timer.h"
43  #include "llvm/Support/raw_ostream.h"
44  #include <memory>
45  #include <system_error>
46  using namespace clang;
47  
48  LLVM_INSTANTIATE_REGISTRY(FrontendPluginRegistry)
49  
50  namespace {
51  
52  class DelegatingDeserializationListener : public ASTDeserializationListener {
53    ASTDeserializationListener *Previous;
54    bool DeletePrevious;
55  
56  public:
57    explicit DelegatingDeserializationListener(
58        ASTDeserializationListener *Previous, bool DeletePrevious)
59        : Previous(Previous), DeletePrevious(DeletePrevious) {}
60    ~DelegatingDeserializationListener() override {
61      if (DeletePrevious)
62        delete Previous;
63    }
64  
65    void ReaderInitialized(ASTReader *Reader) override {
66      if (Previous)
67        Previous->ReaderInitialized(Reader);
68    }
69    void IdentifierRead(serialization::IdentID ID,
70                        IdentifierInfo *II) override {
71      if (Previous)
72        Previous->IdentifierRead(ID, II);
73    }
74    void TypeRead(serialization::TypeIdx Idx, QualType T) override {
75      if (Previous)
76        Previous->TypeRead(Idx, T);
77    }
78    void DeclRead(serialization::DeclID ID, const Decl *D) override {
79      if (Previous)
80        Previous->DeclRead(ID, D);
81    }
82    void SelectorRead(serialization::SelectorID ID, Selector Sel) override {
83      if (Previous)
84        Previous->SelectorRead(ID, Sel);
85    }
86    void MacroDefinitionRead(serialization::PreprocessedEntityID PPID,
87                             MacroDefinitionRecord *MD) override {
88      if (Previous)
89        Previous->MacroDefinitionRead(PPID, MD);
90    }
91  };
92  
93  /// Dumps deserialized declarations.
94  class DeserializedDeclsDumper : public DelegatingDeserializationListener {
95  public:
96    explicit DeserializedDeclsDumper(ASTDeserializationListener *Previous,
97                                     bool DeletePrevious)
98        : DelegatingDeserializationListener(Previous, DeletePrevious) {}
99  
100    void DeclRead(serialization::DeclID ID, const Decl *D) override {
101      llvm::outs() << "PCH DECL: " << D->getDeclKindName();
102      if (const NamedDecl *ND = dyn_cast<NamedDecl>(D)) {
103        llvm::outs() << " - ";
104        ND->printQualifiedName(llvm::outs());
105      }
106      llvm::outs() << "\n";
107  
108      DelegatingDeserializationListener::DeclRead(ID, D);
109    }
110  };
111  
112  /// Checks deserialized declarations and emits error if a name
113  /// matches one given in command-line using -error-on-deserialized-decl.
114  class DeserializedDeclsChecker : public DelegatingDeserializationListener {
115    ASTContext &Ctx;
116    std::set<std::string> NamesToCheck;
117  
118  public:
119    DeserializedDeclsChecker(ASTContext &Ctx,
120                             const std::set<std::string> &NamesToCheck,
121                             ASTDeserializationListener *Previous,
122                             bool DeletePrevious)
123        : DelegatingDeserializationListener(Previous, DeletePrevious), Ctx(Ctx),
124          NamesToCheck(NamesToCheck) {}
125  
126    void DeclRead(serialization::DeclID ID, const Decl *D) override {
127      if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
128        if (NamesToCheck.find(ND->getNameAsString()) != NamesToCheck.end()) {
129          unsigned DiagID
130            = Ctx.getDiagnostics().getCustomDiagID(DiagnosticsEngine::Error,
131                                                   "%0 was deserialized");
132          Ctx.getDiagnostics().Report(Ctx.getFullLoc(D->getLocation()), DiagID)
133              << ND;
134        }
135  
136      DelegatingDeserializationListener::DeclRead(ID, D);
137    }
138  };
139  
140  } // end anonymous namespace
141  
142  FrontendAction::FrontendAction() : Instance(nullptr) {}
143  
144  FrontendAction::~FrontendAction() {}
145  
146  void FrontendAction::setCurrentInput(const FrontendInputFile &CurrentInput,
147                                       std::unique_ptr<ASTUnit> AST) {
148    this->CurrentInput = CurrentInput;
149    CurrentASTUnit = std::move(AST);
150  }
151  
152  Module *FrontendAction::getCurrentModule() const {
153    CompilerInstance &CI = getCompilerInstance();
154    return CI.getPreprocessor().getHeaderSearchInfo().lookupModule(
155        CI.getLangOpts().CurrentModule, SourceLocation(), /*AllowSearch*/false);
156  }
157  
158  std::unique_ptr<ASTConsumer>
159  FrontendAction::CreateWrappedASTConsumer(CompilerInstance &CI,
160                                           StringRef InFile) {
161    std::unique_ptr<ASTConsumer> Consumer = CreateASTConsumer(CI, InFile);
162    if (!Consumer)
163      return nullptr;
164  
165    // Validate -add-plugin args.
166    bool FoundAllPlugins = true;
167    for (const std::string &Arg : CI.getFrontendOpts().AddPluginActions) {
168      bool Found = false;
169      for (const FrontendPluginRegistry::entry &Plugin :
170           FrontendPluginRegistry::entries()) {
171        if (Plugin.getName() == Arg)
172          Found = true;
173      }
174      if (!Found) {
175        CI.getDiagnostics().Report(diag::err_fe_invalid_plugin_name) << Arg;
176        FoundAllPlugins = false;
177      }
178    }
179    if (!FoundAllPlugins)
180      return nullptr;
181  
182    // If there are no registered plugins we don't need to wrap the consumer
183    if (FrontendPluginRegistry::begin() == FrontendPluginRegistry::end())
184      return Consumer;
185  
186    // If this is a code completion run, avoid invoking the plugin consumers
187    if (CI.hasCodeCompletionConsumer())
188      return Consumer;
189  
190    // Collect the list of plugins that go before the main action (in Consumers)
191    // or after it (in AfterConsumers)
192    std::vector<std::unique_ptr<ASTConsumer>> Consumers;
193    std::vector<std::unique_ptr<ASTConsumer>> AfterConsumers;
194    for (const FrontendPluginRegistry::entry &Plugin :
195         FrontendPluginRegistry::entries()) {
196      std::unique_ptr<PluginASTAction> P = Plugin.instantiate();
197      PluginASTAction::ActionType ActionType = P->getActionType();
198      if (ActionType == PluginASTAction::CmdlineAfterMainAction ||
199          ActionType == PluginASTAction::CmdlineBeforeMainAction) {
200        // This is O(|plugins| * |add_plugins|), but since both numbers are
201        // way below 50 in practice, that's ok.
202        if (llvm::is_contained(CI.getFrontendOpts().AddPluginActions,
203                               Plugin.getName())) {
204          if (ActionType == PluginASTAction::CmdlineBeforeMainAction)
205            ActionType = PluginASTAction::AddBeforeMainAction;
206          else
207            ActionType = PluginASTAction::AddAfterMainAction;
208        }
209      }
210      if ((ActionType == PluginASTAction::AddBeforeMainAction ||
211           ActionType == PluginASTAction::AddAfterMainAction) &&
212          P->ParseArgs(
213              CI,
214              CI.getFrontendOpts().PluginArgs[std::string(Plugin.getName())])) {
215        std::unique_ptr<ASTConsumer> PluginConsumer = P->CreateASTConsumer(CI, InFile);
216        if (ActionType == PluginASTAction::AddBeforeMainAction) {
217          Consumers.push_back(std::move(PluginConsumer));
218        } else {
219          AfterConsumers.push_back(std::move(PluginConsumer));
220        }
221      }
222    }
223  
224    // Add to Consumers the main consumer, then all the plugins that go after it
225    Consumers.push_back(std::move(Consumer));
226    if (!AfterConsumers.empty()) {
227      // If we have plugins after the main consumer, which may be the codegen
228      // action, they likely will need the ASTContext, so don't clear it in the
229      // codegen action.
230      CI.getCodeGenOpts().ClearASTBeforeBackend = false;
231      for (auto &C : AfterConsumers)
232        Consumers.push_back(std::move(C));
233    }
234  
235    return std::make_unique<MultiplexConsumer>(std::move(Consumers));
236  }
237  
238  /// For preprocessed files, if the first line is the linemarker and specifies
239  /// the original source file name, use that name as the input file name.
240  /// Returns the location of the first token after the line marker directive.
241  ///
242  /// \param CI The compiler instance.
243  /// \param InputFile Populated with the filename from the line marker.
244  /// \param IsModuleMap If \c true, add a line note corresponding to this line
245  ///        directive. (We need to do this because the directive will not be
246  ///        visited by the preprocessor.)
247  static SourceLocation ReadOriginalFileName(CompilerInstance &CI,
248                                             std::string &InputFile,
249                                             bool IsModuleMap = false) {
250    auto &SourceMgr = CI.getSourceManager();
251    auto MainFileID = SourceMgr.getMainFileID();
252  
253    auto MainFileBuf = SourceMgr.getBufferOrNone(MainFileID);
254    if (!MainFileBuf)
255      return SourceLocation();
256  
257    std::unique_ptr<Lexer> RawLexer(
258        new Lexer(MainFileID, *MainFileBuf, SourceMgr, CI.getLangOpts()));
259  
260    // If the first line has the syntax of
261    //
262    // # NUM "FILENAME"
263    //
264    // we use FILENAME as the input file name.
265    Token T;
266    if (RawLexer->LexFromRawLexer(T) || T.getKind() != tok::hash)
267      return SourceLocation();
268    if (RawLexer->LexFromRawLexer(T) || T.isAtStartOfLine() ||
269        T.getKind() != tok::numeric_constant)
270      return SourceLocation();
271  
272    unsigned LineNo;
273    SourceLocation LineNoLoc = T.getLocation();
274    if (IsModuleMap) {
275      llvm::SmallString<16> Buffer;
276      if (Lexer::getSpelling(LineNoLoc, Buffer, SourceMgr, CI.getLangOpts())
277              .getAsInteger(10, LineNo))
278        return SourceLocation();
279    }
280  
281    RawLexer->LexFromRawLexer(T);
282    if (T.isAtStartOfLine() || T.getKind() != tok::string_literal)
283      return SourceLocation();
284  
285    StringLiteralParser Literal(T, CI.getPreprocessor());
286    if (Literal.hadError)
287      return SourceLocation();
288    RawLexer->LexFromRawLexer(T);
289    if (T.isNot(tok::eof) && !T.isAtStartOfLine())
290      return SourceLocation();
291    InputFile = Literal.GetString().str();
292  
293    if (IsModuleMap)
294      CI.getSourceManager().AddLineNote(
295          LineNoLoc, LineNo, SourceMgr.getLineTableFilenameID(InputFile), false,
296          false, SrcMgr::C_User_ModuleMap);
297  
298    return T.getLocation();
299  }
300  
301  static SmallVectorImpl<char> &
302  operator+=(SmallVectorImpl<char> &Includes, StringRef RHS) {
303    Includes.append(RHS.begin(), RHS.end());
304    return Includes;
305  }
306  
307  static void addHeaderInclude(StringRef HeaderName,
308                               SmallVectorImpl<char> &Includes,
309                               const LangOptions &LangOpts,
310                               bool IsExternC) {
311    if (IsExternC && LangOpts.CPlusPlus)
312      Includes += "extern \"C\" {\n";
313    if (LangOpts.ObjC)
314      Includes += "#import \"";
315    else
316      Includes += "#include \"";
317  
318    Includes += HeaderName;
319  
320    Includes += "\"\n";
321    if (IsExternC && LangOpts.CPlusPlus)
322      Includes += "}\n";
323  }
324  
325  /// Collect the set of header includes needed to construct the given
326  /// module and update the TopHeaders file set of the module.
327  ///
328  /// \param Module The module we're collecting includes from.
329  ///
330  /// \param Includes Will be augmented with the set of \#includes or \#imports
331  /// needed to load all of the named headers.
332  static std::error_code collectModuleHeaderIncludes(
333      const LangOptions &LangOpts, FileManager &FileMgr, DiagnosticsEngine &Diag,
334      ModuleMap &ModMap, clang::Module *Module, SmallVectorImpl<char> &Includes) {
335    // Don't collect any headers for unavailable modules.
336    if (!Module->isAvailable())
337      return std::error_code();
338  
339    // Resolve all lazy header directives to header files.
340    ModMap.resolveHeaderDirectives(Module, /*File=*/std::nullopt);
341  
342    // If any headers are missing, we can't build this module. In most cases,
343    // diagnostics for this should have already been produced; we only get here
344    // if explicit stat information was provided.
345    // FIXME: If the name resolves to a file with different stat information,
346    // produce a better diagnostic.
347    if (!Module->MissingHeaders.empty()) {
348      auto &MissingHeader = Module->MissingHeaders.front();
349      Diag.Report(MissingHeader.FileNameLoc, diag::err_module_header_missing)
350        << MissingHeader.IsUmbrella << MissingHeader.FileName;
351      return std::error_code();
352    }
353  
354    // Add includes for each of these headers.
355    for (auto HK : {Module::HK_Normal, Module::HK_Private}) {
356      for (Module::Header &H : Module->Headers[HK]) {
357        Module->addTopHeader(H.Entry);
358        // Use the path as specified in the module map file. We'll look for this
359        // file relative to the module build directory (the directory containing
360        // the module map file) so this will find the same file that we found
361        // while parsing the module map.
362        addHeaderInclude(H.PathRelativeToRootModuleDirectory, Includes, LangOpts,
363                         Module->IsExternC);
364      }
365    }
366    // Note that Module->PrivateHeaders will not be a TopHeader.
367  
368    if (std::optional<Module::Header> UmbrellaHeader =
369            Module->getUmbrellaHeaderAsWritten()) {
370      Module->addTopHeader(UmbrellaHeader->Entry);
371      if (Module->Parent)
372        // Include the umbrella header for submodules.
373        addHeaderInclude(UmbrellaHeader->PathRelativeToRootModuleDirectory,
374                         Includes, LangOpts, Module->IsExternC);
375    } else if (std::optional<Module::DirectoryName> UmbrellaDir =
376                   Module->getUmbrellaDirAsWritten()) {
377      // Add all of the headers we find in this subdirectory.
378      std::error_code EC;
379      SmallString<128> DirNative;
380      llvm::sys::path::native(UmbrellaDir->Entry.getName(), DirNative);
381  
382      llvm::vfs::FileSystem &FS = FileMgr.getVirtualFileSystem();
383      SmallVector<std::pair<std::string, FileEntryRef>, 8> Headers;
384      for (llvm::vfs::recursive_directory_iterator Dir(FS, DirNative, EC), End;
385           Dir != End && !EC; Dir.increment(EC)) {
386        // Check whether this entry has an extension typically associated with
387        // headers.
388        if (!llvm::StringSwitch<bool>(llvm::sys::path::extension(Dir->path()))
389                 .Cases(".h", ".H", ".hh", ".hpp", true)
390                 .Default(false))
391          continue;
392  
393        auto Header = FileMgr.getOptionalFileRef(Dir->path());
394        // FIXME: This shouldn't happen unless there is a file system race. Is
395        // that worth diagnosing?
396        if (!Header)
397          continue;
398  
399        // If this header is marked 'unavailable' in this module, don't include
400        // it.
401        if (ModMap.isHeaderUnavailableInModule(*Header, Module))
402          continue;
403  
404        // Compute the relative path from the directory to this file.
405        SmallVector<StringRef, 16> Components;
406        auto PathIt = llvm::sys::path::rbegin(Dir->path());
407        for (int I = 0; I != Dir.level() + 1; ++I, ++PathIt)
408          Components.push_back(*PathIt);
409        SmallString<128> RelativeHeader(
410            UmbrellaDir->PathRelativeToRootModuleDirectory);
411        for (auto It = Components.rbegin(), End = Components.rend(); It != End;
412             ++It)
413          llvm::sys::path::append(RelativeHeader, *It);
414  
415        std::string RelName = RelativeHeader.c_str();
416        Headers.push_back(std::make_pair(RelName, *Header));
417      }
418  
419      if (EC)
420        return EC;
421  
422      // Sort header paths and make the header inclusion order deterministic
423      // across different OSs and filesystems.
424      llvm::sort(Headers, llvm::less_first());
425      for (auto &H : Headers) {
426        // Include this header as part of the umbrella directory.
427        Module->addTopHeader(H.second);
428        addHeaderInclude(H.first, Includes, LangOpts, Module->IsExternC);
429      }
430    }
431  
432    // Recurse into submodules.
433    for (auto *Submodule : Module->submodules())
434      if (std::error_code Err = collectModuleHeaderIncludes(
435              LangOpts, FileMgr, Diag, ModMap, Submodule, Includes))
436        return Err;
437  
438    return std::error_code();
439  }
440  
441  static bool loadModuleMapForModuleBuild(CompilerInstance &CI, bool IsSystem,
442                                          bool IsPreprocessed,
443                                          std::string &PresumedModuleMapFile,
444                                          unsigned &Offset) {
445    auto &SrcMgr = CI.getSourceManager();
446    HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
447  
448    // Map the current input to a file.
449    FileID ModuleMapID = SrcMgr.getMainFileID();
450    OptionalFileEntryRef ModuleMap = SrcMgr.getFileEntryRefForID(ModuleMapID);
451    assert(ModuleMap && "MainFileID without FileEntry");
452  
453    // If the module map is preprocessed, handle the initial line marker;
454    // line directives are not part of the module map syntax in general.
455    Offset = 0;
456    if (IsPreprocessed) {
457      SourceLocation EndOfLineMarker =
458          ReadOriginalFileName(CI, PresumedModuleMapFile, /*IsModuleMap*/ true);
459      if (EndOfLineMarker.isValid())
460        Offset = CI.getSourceManager().getDecomposedLoc(EndOfLineMarker).second;
461    }
462  
463    // Load the module map file.
464    if (HS.loadModuleMapFile(*ModuleMap, IsSystem, ModuleMapID, &Offset,
465                             PresumedModuleMapFile))
466      return true;
467  
468    if (SrcMgr.getBufferOrFake(ModuleMapID).getBufferSize() == Offset)
469      Offset = 0;
470  
471    // Infer framework module if possible.
472    if (HS.getModuleMap().canInferFrameworkModule(ModuleMap->getDir())) {
473      SmallString<128> InferredFrameworkPath = ModuleMap->getDir().getName();
474      llvm::sys::path::append(InferredFrameworkPath,
475                              CI.getLangOpts().ModuleName + ".framework");
476      if (auto Dir =
477              CI.getFileManager().getOptionalDirectoryRef(InferredFrameworkPath))
478        (void)HS.getModuleMap().inferFrameworkModule(*Dir, IsSystem, nullptr);
479    }
480  
481    return false;
482  }
483  
484  static Module *prepareToBuildModule(CompilerInstance &CI,
485                                      StringRef ModuleMapFilename) {
486    if (CI.getLangOpts().CurrentModule.empty()) {
487      CI.getDiagnostics().Report(diag::err_missing_module_name);
488  
489      // FIXME: Eventually, we could consider asking whether there was just
490      // a single module described in the module map, and use that as a
491      // default. Then it would be fairly trivial to just "compile" a module
492      // map with a single module (the common case).
493      return nullptr;
494    }
495  
496    // Dig out the module definition.
497    HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
498    Module *M = HS.lookupModule(CI.getLangOpts().CurrentModule, SourceLocation(),
499                                /*AllowSearch=*/true);
500    if (!M) {
501      CI.getDiagnostics().Report(diag::err_missing_module)
502        << CI.getLangOpts().CurrentModule << ModuleMapFilename;
503  
504      return nullptr;
505    }
506  
507    // Check whether we can build this module at all.
508    if (Preprocessor::checkModuleIsAvailable(CI.getLangOpts(), CI.getTarget(),
509                                             CI.getDiagnostics(), M))
510      return nullptr;
511  
512    // Inform the preprocessor that includes from within the input buffer should
513    // be resolved relative to the build directory of the module map file.
514    CI.getPreprocessor().setMainFileDir(*M->Directory);
515  
516    // If the module was inferred from a different module map (via an expanded
517    // umbrella module definition), track that fact.
518    // FIXME: It would be preferable to fill this in as part of processing
519    // the module map, rather than adding it after the fact.
520    StringRef OriginalModuleMapName = CI.getFrontendOpts().OriginalModuleMap;
521    if (!OriginalModuleMapName.empty()) {
522      auto OriginalModuleMap =
523          CI.getFileManager().getFile(OriginalModuleMapName,
524                                      /*openFile*/ true);
525      if (!OriginalModuleMap) {
526        CI.getDiagnostics().Report(diag::err_module_map_not_found)
527          << OriginalModuleMapName;
528        return nullptr;
529      }
530      if (*OriginalModuleMap != CI.getSourceManager().getFileEntryForID(
531                                   CI.getSourceManager().getMainFileID())) {
532        M->IsInferred = true;
533        CI.getPreprocessor().getHeaderSearchInfo().getModuleMap()
534          .setInferredModuleAllowedBy(M, *OriginalModuleMap);
535      }
536    }
537  
538    // If we're being run from the command-line, the module build stack will not
539    // have been filled in yet, so complete it now in order to allow us to detect
540    // module cycles.
541    SourceManager &SourceMgr = CI.getSourceManager();
542    if (SourceMgr.getModuleBuildStack().empty())
543      SourceMgr.pushModuleBuildStack(CI.getLangOpts().CurrentModule,
544                                     FullSourceLoc(SourceLocation(), SourceMgr));
545    return M;
546  }
547  
548  /// Compute the input buffer that should be used to build the specified module.
549  static std::unique_ptr<llvm::MemoryBuffer>
550  getInputBufferForModule(CompilerInstance &CI, Module *M) {
551    FileManager &FileMgr = CI.getFileManager();
552  
553    // Collect the set of #includes we need to build the module.
554    SmallString<256> HeaderContents;
555    std::error_code Err = std::error_code();
556    if (std::optional<Module::Header> UmbrellaHeader =
557            M->getUmbrellaHeaderAsWritten())
558      addHeaderInclude(UmbrellaHeader->PathRelativeToRootModuleDirectory,
559                       HeaderContents, CI.getLangOpts(), M->IsExternC);
560    Err = collectModuleHeaderIncludes(
561        CI.getLangOpts(), FileMgr, CI.getDiagnostics(),
562        CI.getPreprocessor().getHeaderSearchInfo().getModuleMap(), M,
563        HeaderContents);
564  
565    if (Err) {
566      CI.getDiagnostics().Report(diag::err_module_cannot_create_includes)
567        << M->getFullModuleName() << Err.message();
568      return nullptr;
569    }
570  
571    return llvm::MemoryBuffer::getMemBufferCopy(
572        HeaderContents, Module::getModuleInputBufferName());
573  }
574  
575  bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
576                                       const FrontendInputFile &RealInput) {
577    FrontendInputFile Input(RealInput);
578    assert(!Instance && "Already processing a source file!");
579    assert(!Input.isEmpty() && "Unexpected empty filename!");
580    setCurrentInput(Input);
581    setCompilerInstance(&CI);
582  
583    bool HasBegunSourceFile = false;
584    bool ReplayASTFile = Input.getKind().getFormat() == InputKind::Precompiled &&
585                         usesPreprocessorOnly();
586  
587    // If we fail, reset state since the client will not end up calling the
588    // matching EndSourceFile(). All paths that return true should release this.
589    auto FailureCleanup = llvm::make_scope_exit([&]() {
590      if (HasBegunSourceFile)
591        CI.getDiagnosticClient().EndSourceFile();
592      CI.setASTConsumer(nullptr);
593      CI.clearOutputFiles(/*EraseFiles=*/true);
594      CI.getLangOpts().setCompilingModule(LangOptions::CMK_None);
595      setCurrentInput(FrontendInputFile());
596      setCompilerInstance(nullptr);
597    });
598  
599    if (!BeginInvocation(CI))
600      return false;
601  
602    // If we're replaying the build of an AST file, import it and set up
603    // the initial state from its build.
604    if (ReplayASTFile) {
605      IntrusiveRefCntPtr<DiagnosticsEngine> Diags(&CI.getDiagnostics());
606  
607      // The AST unit populates its own diagnostics engine rather than ours.
608      IntrusiveRefCntPtr<DiagnosticsEngine> ASTDiags(
609          new DiagnosticsEngine(Diags->getDiagnosticIDs(),
610                                &Diags->getDiagnosticOptions()));
611      ASTDiags->setClient(Diags->getClient(), /*OwnsClient*/false);
612  
613      // FIXME: What if the input is a memory buffer?
614      StringRef InputFile = Input.getFile();
615  
616      std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromASTFile(
617          std::string(InputFile), CI.getPCHContainerReader(),
618          ASTUnit::LoadPreprocessorOnly, ASTDiags, CI.getFileSystemOpts(),
619          /*HeaderSearchOptions=*/nullptr, CI.getCodeGenOpts().DebugTypeExtRefs);
620      if (!AST)
621        return false;
622  
623      // Options relating to how we treat the input (but not what we do with it)
624      // are inherited from the AST unit.
625      CI.getHeaderSearchOpts() = AST->getHeaderSearchOpts();
626      CI.getPreprocessorOpts() = AST->getPreprocessorOpts();
627      CI.getLangOpts() = AST->getLangOpts();
628  
629      // Set the shared objects, these are reset when we finish processing the
630      // file, otherwise the CompilerInstance will happily destroy them.
631      CI.setFileManager(&AST->getFileManager());
632      CI.createSourceManager(CI.getFileManager());
633      CI.getSourceManager().initializeForReplay(AST->getSourceManager());
634  
635      // Preload all the module files loaded transitively by the AST unit. Also
636      // load all module map files that were parsed as part of building the AST
637      // unit.
638      if (auto ASTReader = AST->getASTReader()) {
639        auto &MM = ASTReader->getModuleManager();
640        auto &PrimaryModule = MM.getPrimaryModule();
641  
642        for (serialization::ModuleFile &MF : MM)
643          if (&MF != &PrimaryModule)
644            CI.getFrontendOpts().ModuleFiles.push_back(MF.FileName);
645  
646        ASTReader->visitTopLevelModuleMaps(PrimaryModule, [&](FileEntryRef FE) {
647          CI.getFrontendOpts().ModuleMapFiles.push_back(
648              std::string(FE.getName()));
649        });
650      }
651  
652      // Set up the input file for replay purposes.
653      auto Kind = AST->getInputKind();
654      if (Kind.getFormat() == InputKind::ModuleMap) {
655        Module *ASTModule =
656            AST->getPreprocessor().getHeaderSearchInfo().lookupModule(
657                AST->getLangOpts().CurrentModule, SourceLocation(),
658                /*AllowSearch*/ false);
659        assert(ASTModule && "module file does not define its own module");
660        Input = FrontendInputFile(ASTModule->PresumedModuleMapFile, Kind);
661      } else {
662        auto &OldSM = AST->getSourceManager();
663        FileID ID = OldSM.getMainFileID();
664        if (auto *File = OldSM.getFileEntryForID(ID))
665          Input = FrontendInputFile(File->getName(), Kind);
666        else
667          Input = FrontendInputFile(OldSM.getBufferOrFake(ID), Kind);
668      }
669      setCurrentInput(Input, std::move(AST));
670    }
671  
672    // AST files follow a very different path, since they share objects via the
673    // AST unit.
674    if (Input.getKind().getFormat() == InputKind::Precompiled) {
675      assert(!usesPreprocessorOnly() && "this case was handled above");
676      assert(hasASTFileSupport() &&
677             "This action does not have AST file support!");
678  
679      IntrusiveRefCntPtr<DiagnosticsEngine> Diags(&CI.getDiagnostics());
680  
681      // FIXME: What if the input is a memory buffer?
682      StringRef InputFile = Input.getFile();
683  
684      std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromASTFile(
685          std::string(InputFile), CI.getPCHContainerReader(),
686          ASTUnit::LoadEverything, Diags, CI.getFileSystemOpts(),
687          CI.getHeaderSearchOptsPtr(),
688          CI.getCodeGenOpts().DebugTypeExtRefs);
689  
690      if (!AST)
691        return false;
692  
693      // Inform the diagnostic client we are processing a source file.
694      CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(), nullptr);
695      HasBegunSourceFile = true;
696  
697      // Set the shared objects, these are reset when we finish processing the
698      // file, otherwise the CompilerInstance will happily destroy them.
699      CI.setFileManager(&AST->getFileManager());
700      CI.setSourceManager(&AST->getSourceManager());
701      CI.setPreprocessor(AST->getPreprocessorPtr());
702      Preprocessor &PP = CI.getPreprocessor();
703      PP.getBuiltinInfo().initializeBuiltins(PP.getIdentifierTable(),
704                                             PP.getLangOpts());
705      CI.setASTContext(&AST->getASTContext());
706  
707      setCurrentInput(Input, std::move(AST));
708  
709      // Initialize the action.
710      if (!BeginSourceFileAction(CI))
711        return false;
712  
713      // Create the AST consumer.
714      CI.setASTConsumer(CreateWrappedASTConsumer(CI, InputFile));
715      if (!CI.hasASTConsumer())
716        return false;
717  
718      FailureCleanup.release();
719      return true;
720    }
721  
722    // Set up the file and source managers, if needed.
723    if (!CI.hasFileManager()) {
724      if (!CI.createFileManager()) {
725        return false;
726      }
727    }
728    if (!CI.hasSourceManager()) {
729      CI.createSourceManager(CI.getFileManager());
730      if (CI.getDiagnosticOpts().getFormat() == DiagnosticOptions::SARIF) {
731        static_cast<SARIFDiagnosticPrinter *>(&CI.getDiagnosticClient())
732            ->setSarifWriter(
733                std::make_unique<SarifDocumentWriter>(CI.getSourceManager()));
734      }
735    }
736  
737    // Set up embedding for any specified files. Do this before we load any
738    // source files, including the primary module map for the compilation.
739    for (const auto &F : CI.getFrontendOpts().ModulesEmbedFiles) {
740      if (auto FE = CI.getFileManager().getFile(F, /*openFile*/true))
741        CI.getSourceManager().setFileIsTransient(*FE);
742      else
743        CI.getDiagnostics().Report(diag::err_modules_embed_file_not_found) << F;
744    }
745    if (CI.getFrontendOpts().ModulesEmbedAllFiles)
746      CI.getSourceManager().setAllFilesAreTransient(true);
747  
748    // IR files bypass the rest of initialization.
749    if (Input.getKind().getLanguage() == Language::LLVM_IR) {
750      assert(hasIRSupport() &&
751             "This action does not have IR file support!");
752  
753      // Inform the diagnostic client we are processing a source file.
754      CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(), nullptr);
755      HasBegunSourceFile = true;
756  
757      // Initialize the action.
758      if (!BeginSourceFileAction(CI))
759        return false;
760  
761      // Initialize the main file entry.
762      if (!CI.InitializeSourceManager(CurrentInput))
763        return false;
764  
765      FailureCleanup.release();
766      return true;
767    }
768  
769    // If the implicit PCH include is actually a directory, rather than
770    // a single file, search for a suitable PCH file in that directory.
771    if (!CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
772      FileManager &FileMgr = CI.getFileManager();
773      PreprocessorOptions &PPOpts = CI.getPreprocessorOpts();
774      StringRef PCHInclude = PPOpts.ImplicitPCHInclude;
775      std::string SpecificModuleCachePath = CI.getSpecificModuleCachePath();
776      if (auto PCHDir = FileMgr.getOptionalDirectoryRef(PCHInclude)) {
777        std::error_code EC;
778        SmallString<128> DirNative;
779        llvm::sys::path::native(PCHDir->getName(), DirNative);
780        bool Found = false;
781        llvm::vfs::FileSystem &FS = FileMgr.getVirtualFileSystem();
782        for (llvm::vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC),
783                                           DirEnd;
784             Dir != DirEnd && !EC; Dir.increment(EC)) {
785          // Check whether this is an acceptable AST file.
786          if (ASTReader::isAcceptableASTFile(
787                  Dir->path(), FileMgr, CI.getModuleCache(),
788                  CI.getPCHContainerReader(), CI.getLangOpts(),
789                  CI.getTargetOpts(), CI.getPreprocessorOpts(),
790                  SpecificModuleCachePath, /*RequireStrictOptionMatches=*/true)) {
791            PPOpts.ImplicitPCHInclude = std::string(Dir->path());
792            Found = true;
793            break;
794          }
795        }
796  
797        if (!Found) {
798          CI.getDiagnostics().Report(diag::err_fe_no_pch_in_dir) << PCHInclude;
799          return false;
800        }
801      }
802    }
803  
804    // Set up the preprocessor if needed. When parsing model files the
805    // preprocessor of the original source is reused.
806    if (!isModelParsingAction())
807      CI.createPreprocessor(getTranslationUnitKind());
808  
809    // Inform the diagnostic client we are processing a source file.
810    CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(),
811                                             &CI.getPreprocessor());
812    HasBegunSourceFile = true;
813  
814    // Handle C++20 header units.
815    // Here, the user has the option to specify that the header name should be
816    // looked up in the pre-processor search paths (and the main filename as
817    // passed by the driver might therefore be incomplete until that look-up).
818    if (CI.getLangOpts().CPlusPlusModules && Input.getKind().isHeaderUnit() &&
819        !Input.getKind().isPreprocessed()) {
820      StringRef FileName = Input.getFile();
821      InputKind Kind = Input.getKind();
822      if (Kind.getHeaderUnitKind() != InputKind::HeaderUnit_Abs) {
823        assert(CI.hasPreprocessor() &&
824               "trying to build a header unit without a Pre-processor?");
825        HeaderSearch &HS = CI.getPreprocessor().getHeaderSearchInfo();
826        // Relative searches begin from CWD.
827        auto Dir = CI.getFileManager().getOptionalDirectoryRef(".");
828        SmallVector<std::pair<const FileEntry *, DirectoryEntryRef>, 1> CWD;
829        CWD.push_back({nullptr, *Dir});
830        OptionalFileEntryRef FE =
831            HS.LookupFile(FileName, SourceLocation(),
832                          /*Angled*/ Input.getKind().getHeaderUnitKind() ==
833                              InputKind::HeaderUnit_System,
834                          nullptr, nullptr, CWD, nullptr, nullptr, nullptr,
835                          nullptr, nullptr, nullptr);
836        if (!FE) {
837          CI.getDiagnostics().Report(diag::err_module_header_file_not_found)
838              << FileName;
839          return false;
840        }
841        // We now have the filename...
842        FileName = FE->getFileEntry().getName();
843        // ... still a header unit, but now use the path as written.
844        Kind = Input.getKind().withHeaderUnit(InputKind::HeaderUnit_Abs);
845        Input = FrontendInputFile(FileName, Kind, Input.isSystem());
846      }
847      // Unless the user has overridden the name, the header unit module name is
848      // the pathname for the file.
849      if (CI.getLangOpts().ModuleName.empty())
850        CI.getLangOpts().ModuleName = std::string(FileName);
851      CI.getLangOpts().CurrentModule = CI.getLangOpts().ModuleName;
852    }
853  
854    if (!CI.InitializeSourceManager(Input))
855      return false;
856  
857    if (CI.getLangOpts().CPlusPlusModules && Input.getKind().isHeaderUnit() &&
858        Input.getKind().isPreprocessed() && !usesPreprocessorOnly()) {
859      // We have an input filename like foo.iih, but we want to find the right
860      // module name (and original file, to build the map entry).
861      // Check if the first line specifies the original source file name with a
862      // linemarker.
863      std::string PresumedInputFile = std::string(getCurrentFileOrBufferName());
864      ReadOriginalFileName(CI, PresumedInputFile);
865      // Unless the user overrides this, the module name is the name by which the
866      // original file was known.
867      if (CI.getLangOpts().ModuleName.empty())
868        CI.getLangOpts().ModuleName = std::string(PresumedInputFile);
869      CI.getLangOpts().CurrentModule = CI.getLangOpts().ModuleName;
870    }
871  
872    // For module map files, we first parse the module map and synthesize a
873    // "<module-includes>" buffer before more conventional processing.
874    if (Input.getKind().getFormat() == InputKind::ModuleMap) {
875      CI.getLangOpts().setCompilingModule(LangOptions::CMK_ModuleMap);
876  
877      std::string PresumedModuleMapFile;
878      unsigned OffsetToContents;
879      if (loadModuleMapForModuleBuild(CI, Input.isSystem(),
880                                      Input.isPreprocessed(),
881                                      PresumedModuleMapFile, OffsetToContents))
882        return false;
883  
884      auto *CurrentModule = prepareToBuildModule(CI, Input.getFile());
885      if (!CurrentModule)
886        return false;
887  
888      CurrentModule->PresumedModuleMapFile = PresumedModuleMapFile;
889  
890      if (OffsetToContents)
891        // If the module contents are in the same file, skip to them.
892        CI.getPreprocessor().setSkipMainFilePreamble(OffsetToContents, true);
893      else {
894        // Otherwise, convert the module description to a suitable input buffer.
895        auto Buffer = getInputBufferForModule(CI, CurrentModule);
896        if (!Buffer)
897          return false;
898  
899        // Reinitialize the main file entry to refer to the new input.
900        auto Kind = CurrentModule->IsSystem ? SrcMgr::C_System : SrcMgr::C_User;
901        auto &SourceMgr = CI.getSourceManager();
902        auto BufferID = SourceMgr.createFileID(std::move(Buffer), Kind);
903        assert(BufferID.isValid() && "couldn't create module buffer ID");
904        SourceMgr.setMainFileID(BufferID);
905      }
906    }
907  
908    // Initialize the action.
909    if (!BeginSourceFileAction(CI))
910      return false;
911  
912    // If we were asked to load any module map files, do so now.
913    for (const auto &Filename : CI.getFrontendOpts().ModuleMapFiles) {
914      if (auto File = CI.getFileManager().getOptionalFileRef(Filename))
915        CI.getPreprocessor().getHeaderSearchInfo().loadModuleMapFile(
916            *File, /*IsSystem*/false);
917      else
918        CI.getDiagnostics().Report(diag::err_module_map_not_found) << Filename;
919    }
920  
921    // If compiling implementation of a module, load its module map file now.
922    (void)CI.getPreprocessor().getCurrentModuleImplementation();
923  
924    // Add a module declaration scope so that modules from -fmodule-map-file
925    // arguments may shadow modules found implicitly in search paths.
926    CI.getPreprocessor()
927        .getHeaderSearchInfo()
928        .getModuleMap()
929        .finishModuleDeclarationScope();
930  
931    // Create the AST context and consumer unless this is a preprocessor only
932    // action.
933    if (!usesPreprocessorOnly()) {
934      // Parsing a model file should reuse the existing ASTContext.
935      if (!isModelParsingAction())
936        CI.createASTContext();
937  
938      // For preprocessed files, check if the first line specifies the original
939      // source file name with a linemarker.
940      std::string PresumedInputFile = std::string(getCurrentFileOrBufferName());
941      if (Input.isPreprocessed())
942        ReadOriginalFileName(CI, PresumedInputFile);
943  
944      std::unique_ptr<ASTConsumer> Consumer =
945          CreateWrappedASTConsumer(CI, PresumedInputFile);
946      if (!Consumer)
947        return false;
948  
949      // FIXME: should not overwrite ASTMutationListener when parsing model files?
950      if (!isModelParsingAction())
951        CI.getASTContext().setASTMutationListener(Consumer->GetASTMutationListener());
952  
953      if (!CI.getPreprocessorOpts().ChainedIncludes.empty()) {
954        // Convert headers to PCH and chain them.
955        IntrusiveRefCntPtr<ExternalSemaSource> source, FinalReader;
956        source = createChainedIncludesSource(CI, FinalReader);
957        if (!source)
958          return false;
959        CI.setASTReader(static_cast<ASTReader *>(FinalReader.get()));
960        CI.getASTContext().setExternalSource(source);
961      } else if (CI.getLangOpts().Modules ||
962                 !CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
963        // Use PCM or PCH.
964        assert(hasPCHSupport() && "This action does not have PCH support!");
965        ASTDeserializationListener *DeserialListener =
966            Consumer->GetASTDeserializationListener();
967        bool DeleteDeserialListener = false;
968        if (CI.getPreprocessorOpts().DumpDeserializedPCHDecls) {
969          DeserialListener = new DeserializedDeclsDumper(DeserialListener,
970                                                         DeleteDeserialListener);
971          DeleteDeserialListener = true;
972        }
973        if (!CI.getPreprocessorOpts().DeserializedPCHDeclsToErrorOn.empty()) {
974          DeserialListener = new DeserializedDeclsChecker(
975              CI.getASTContext(),
976              CI.getPreprocessorOpts().DeserializedPCHDeclsToErrorOn,
977              DeserialListener, DeleteDeserialListener);
978          DeleteDeserialListener = true;
979        }
980        if (!CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
981          CI.createPCHExternalASTSource(
982              CI.getPreprocessorOpts().ImplicitPCHInclude,
983              CI.getPreprocessorOpts().DisablePCHOrModuleValidation,
984              CI.getPreprocessorOpts().AllowPCHWithCompilerErrors,
985              DeserialListener, DeleteDeserialListener);
986          if (!CI.getASTContext().getExternalSource())
987            return false;
988        }
989        // If modules are enabled, create the AST reader before creating
990        // any builtins, so that all declarations know that they might be
991        // extended by an external source.
992        if (CI.getLangOpts().Modules || !CI.hasASTContext() ||
993            !CI.getASTContext().getExternalSource()) {
994          CI.createASTReader();
995          CI.getASTReader()->setDeserializationListener(DeserialListener,
996                                                        DeleteDeserialListener);
997        }
998      }
999  
1000      CI.setASTConsumer(std::move(Consumer));
1001      if (!CI.hasASTConsumer())
1002        return false;
1003    }
1004  
1005    // Initialize built-in info as long as we aren't using an external AST
1006    // source.
1007    if (CI.getLangOpts().Modules || !CI.hasASTContext() ||
1008        !CI.getASTContext().getExternalSource()) {
1009      Preprocessor &PP = CI.getPreprocessor();
1010      PP.getBuiltinInfo().initializeBuiltins(PP.getIdentifierTable(),
1011                                             PP.getLangOpts());
1012    } else {
1013      // FIXME: If this is a problem, recover from it by creating a multiplex
1014      // source.
1015      assert((!CI.getLangOpts().Modules || CI.getASTReader()) &&
1016             "modules enabled but created an external source that "
1017             "doesn't support modules");
1018    }
1019  
1020    // If we were asked to load any module files, do so now.
1021    for (const auto &ModuleFile : CI.getFrontendOpts().ModuleFiles)
1022      if (!CI.loadModuleFile(ModuleFile))
1023        return false;
1024  
1025    // If there is a layout overrides file, attach an external AST source that
1026    // provides the layouts from that file.
1027    if (!CI.getFrontendOpts().OverrideRecordLayoutsFile.empty() &&
1028        CI.hasASTContext() && !CI.getASTContext().getExternalSource()) {
1029      IntrusiveRefCntPtr<ExternalASTSource>
1030        Override(new LayoutOverrideSource(
1031                       CI.getFrontendOpts().OverrideRecordLayoutsFile));
1032      CI.getASTContext().setExternalSource(Override);
1033    }
1034  
1035    // Setup HLSL External Sema Source
1036    if (CI.getLangOpts().HLSL && CI.hasASTContext()) {
1037      IntrusiveRefCntPtr<ExternalSemaSource> HLSLSema(
1038          new HLSLExternalSemaSource());
1039      if (auto *SemaSource = dyn_cast_if_present<ExternalSemaSource>(
1040              CI.getASTContext().getExternalSource())) {
1041        IntrusiveRefCntPtr<ExternalSemaSource> MultiSema(
1042            new MultiplexExternalSemaSource(SemaSource, HLSLSema.get()));
1043        CI.getASTContext().setExternalSource(MultiSema);
1044      } else
1045        CI.getASTContext().setExternalSource(HLSLSema);
1046    }
1047  
1048    FailureCleanup.release();
1049    return true;
1050  }
1051  
1052  llvm::Error FrontendAction::Execute() {
1053    CompilerInstance &CI = getCompilerInstance();
1054  
1055    if (CI.hasFrontendTimer()) {
1056      llvm::TimeRegion Timer(CI.getFrontendTimer());
1057      ExecuteAction();
1058    }
1059    else ExecuteAction();
1060  
1061    // If we are supposed to rebuild the global module index, do so now unless
1062    // there were any module-build failures.
1063    if (CI.shouldBuildGlobalModuleIndex() && CI.hasFileManager() &&
1064        CI.hasPreprocessor()) {
1065      StringRef Cache =
1066          CI.getPreprocessor().getHeaderSearchInfo().getModuleCachePath();
1067      if (!Cache.empty()) {
1068        if (llvm::Error Err = GlobalModuleIndex::writeIndex(
1069                CI.getFileManager(), CI.getPCHContainerReader(), Cache)) {
1070          // FIXME this drops the error on the floor, but
1071          // Index/pch-from-libclang.c seems to rely on dropping at least some of
1072          // the error conditions!
1073          consumeError(std::move(Err));
1074        }
1075      }
1076    }
1077  
1078    return llvm::Error::success();
1079  }
1080  
1081  void FrontendAction::EndSourceFile() {
1082    CompilerInstance &CI = getCompilerInstance();
1083  
1084    // Inform the diagnostic client we are done with this source file.
1085    CI.getDiagnosticClient().EndSourceFile();
1086  
1087    // Inform the preprocessor we are done.
1088    if (CI.hasPreprocessor())
1089      CI.getPreprocessor().EndSourceFile();
1090  
1091    // Finalize the action.
1092    EndSourceFileAction();
1093  
1094    // Sema references the ast consumer, so reset sema first.
1095    //
1096    // FIXME: There is more per-file stuff we could just drop here?
1097    bool DisableFree = CI.getFrontendOpts().DisableFree;
1098    if (DisableFree) {
1099      CI.resetAndLeakSema();
1100      CI.resetAndLeakASTContext();
1101      llvm::BuryPointer(CI.takeASTConsumer().get());
1102    } else {
1103      CI.setSema(nullptr);
1104      CI.setASTContext(nullptr);
1105      CI.setASTConsumer(nullptr);
1106    }
1107  
1108    if (CI.getFrontendOpts().ShowStats) {
1109      llvm::errs() << "\nSTATISTICS FOR '" << getCurrentFileOrBufferName() << "':\n";
1110      CI.getPreprocessor().PrintStats();
1111      CI.getPreprocessor().getIdentifierTable().PrintStats();
1112      CI.getPreprocessor().getHeaderSearchInfo().PrintStats();
1113      CI.getSourceManager().PrintStats();
1114      llvm::errs() << "\n";
1115    }
1116  
1117    // Cleanup the output streams, and erase the output files if instructed by the
1118    // FrontendAction.
1119    CI.clearOutputFiles(/*EraseFiles=*/shouldEraseOutputFiles());
1120  
1121    // The resources are owned by AST when the current file is AST.
1122    // So we reset the resources here to avoid users accessing it
1123    // accidently.
1124    if (isCurrentFileAST()) {
1125      if (DisableFree) {
1126        CI.resetAndLeakPreprocessor();
1127        CI.resetAndLeakSourceManager();
1128        CI.resetAndLeakFileManager();
1129        llvm::BuryPointer(std::move(CurrentASTUnit));
1130      } else {
1131        CI.setPreprocessor(nullptr);
1132        CI.setSourceManager(nullptr);
1133        CI.setFileManager(nullptr);
1134      }
1135    }
1136  
1137    setCompilerInstance(nullptr);
1138    setCurrentInput(FrontendInputFile());
1139    CI.getLangOpts().setCompilingModule(LangOptions::CMK_None);
1140  }
1141  
1142  bool FrontendAction::shouldEraseOutputFiles() {
1143    return getCompilerInstance().getDiagnostics().hasErrorOccurred();
1144  }
1145  
1146  //===----------------------------------------------------------------------===//
1147  // Utility Actions
1148  //===----------------------------------------------------------------------===//
1149  
1150  void ASTFrontendAction::ExecuteAction() {
1151    CompilerInstance &CI = getCompilerInstance();
1152    if (!CI.hasPreprocessor())
1153      return;
1154    // This is a fallback: If the client forgets to invoke this, we mark the
1155    // current stack as the bottom. Though not optimal, this could help prevent
1156    // stack overflow during deep recursion.
1157    clang::noteBottomOfStack();
1158  
1159    // FIXME: Move the truncation aspect of this into Sema, we delayed this till
1160    // here so the source manager would be initialized.
1161    if (hasCodeCompletionSupport() &&
1162        !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
1163      CI.createCodeCompletionConsumer();
1164  
1165    // Use a code completion consumer?
1166    CodeCompleteConsumer *CompletionConsumer = nullptr;
1167    if (CI.hasCodeCompletionConsumer())
1168      CompletionConsumer = &CI.getCodeCompletionConsumer();
1169  
1170    if (!CI.hasSema())
1171      CI.createSema(getTranslationUnitKind(), CompletionConsumer);
1172  
1173    ParseAST(CI.getSema(), CI.getFrontendOpts().ShowStats,
1174             CI.getFrontendOpts().SkipFunctionBodies);
1175  }
1176  
1177  void PluginASTAction::anchor() { }
1178  
1179  std::unique_ptr<ASTConsumer>
1180  PreprocessorFrontendAction::CreateASTConsumer(CompilerInstance &CI,
1181                                                StringRef InFile) {
1182    llvm_unreachable("Invalid CreateASTConsumer on preprocessor action!");
1183  }
1184  
1185  bool WrapperFrontendAction::PrepareToExecuteAction(CompilerInstance &CI) {
1186    return WrappedAction->PrepareToExecuteAction(CI);
1187  }
1188  std::unique_ptr<ASTConsumer>
1189  WrapperFrontendAction::CreateASTConsumer(CompilerInstance &CI,
1190                                           StringRef InFile) {
1191    return WrappedAction->CreateASTConsumer(CI, InFile);
1192  }
1193  bool WrapperFrontendAction::BeginInvocation(CompilerInstance &CI) {
1194    return WrappedAction->BeginInvocation(CI);
1195  }
1196  bool WrapperFrontendAction::BeginSourceFileAction(CompilerInstance &CI) {
1197    WrappedAction->setCurrentInput(getCurrentInput());
1198    WrappedAction->setCompilerInstance(&CI);
1199    auto Ret = WrappedAction->BeginSourceFileAction(CI);
1200    // BeginSourceFileAction may change CurrentInput, e.g. during module builds.
1201    setCurrentInput(WrappedAction->getCurrentInput());
1202    return Ret;
1203  }
1204  void WrapperFrontendAction::ExecuteAction() {
1205    WrappedAction->ExecuteAction();
1206  }
1207  void WrapperFrontendAction::EndSourceFile() { WrappedAction->EndSourceFile(); }
1208  void WrapperFrontendAction::EndSourceFileAction() {
1209    WrappedAction->EndSourceFileAction();
1210  }
1211  bool WrapperFrontendAction::shouldEraseOutputFiles() {
1212    return WrappedAction->shouldEraseOutputFiles();
1213  }
1214  
1215  bool WrapperFrontendAction::usesPreprocessorOnly() const {
1216    return WrappedAction->usesPreprocessorOnly();
1217  }
1218  TranslationUnitKind WrapperFrontendAction::getTranslationUnitKind() {
1219    return WrappedAction->getTranslationUnitKind();
1220  }
1221  bool WrapperFrontendAction::hasPCHSupport() const {
1222    return WrappedAction->hasPCHSupport();
1223  }
1224  bool WrapperFrontendAction::hasASTFileSupport() const {
1225    return WrappedAction->hasASTFileSupport();
1226  }
1227  bool WrapperFrontendAction::hasIRSupport() const {
1228    return WrappedAction->hasIRSupport();
1229  }
1230  bool WrapperFrontendAction::hasCodeCompletionSupport() const {
1231    return WrappedAction->hasCodeCompletionSupport();
1232  }
1233  
1234  WrapperFrontendAction::WrapperFrontendAction(
1235      std::unique_ptr<FrontendAction> WrappedAction)
1236    : WrappedAction(std::move(WrappedAction)) {}
1237