1 //===--- FrontendAction.cpp -----------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "clang/Frontend/FrontendAction.h"
11 #include "clang/AST/ASTConsumer.h"
12 #include "clang/AST/ASTContext.h"
13 #include "clang/AST/DeclGroup.h"
14 #include "clang/Frontend/ASTUnit.h"
15 #include "clang/Frontend/CompilerInstance.h"
16 #include "clang/Frontend/FrontendDiagnostic.h"
17 #include "clang/Frontend/FrontendPluginRegistry.h"
18 #include "clang/Frontend/LayoutOverrideSource.h"
19 #include "clang/Frontend/MultiplexConsumer.h"
20 #include "clang/Frontend/Utils.h"
21 #include "clang/Lex/HeaderSearch.h"
22 #include "clang/Lex/LiteralSupport.h"
23 #include "clang/Lex/Preprocessor.h"
24 #include "clang/Lex/PreprocessorOptions.h"
25 #include "clang/Parse/ParseAST.h"
26 #include "clang/Serialization/ASTDeserializationListener.h"
27 #include "clang/Serialization/ASTReader.h"
28 #include "clang/Serialization/GlobalModuleIndex.h"
29 #include "llvm/Support/ErrorHandling.h"
30 #include "llvm/Support/FileSystem.h"
31 #include "llvm/Support/Path.h"
32 #include "llvm/Support/Timer.h"
33 #include "llvm/Support/raw_ostream.h"
34 #include <system_error>
35 using namespace clang;
36 
37 LLVM_INSTANTIATE_REGISTRY(FrontendPluginRegistry)
38 
39 namespace {
40 
41 class DelegatingDeserializationListener : public ASTDeserializationListener {
42   ASTDeserializationListener *Previous;
43   bool DeletePrevious;
44 
45 public:
46   explicit DelegatingDeserializationListener(
47       ASTDeserializationListener *Previous, bool DeletePrevious)
48       : Previous(Previous), DeletePrevious(DeletePrevious) {}
49   ~DelegatingDeserializationListener() override {
50     if (DeletePrevious)
51       delete Previous;
52   }
53 
54   void ReaderInitialized(ASTReader *Reader) override {
55     if (Previous)
56       Previous->ReaderInitialized(Reader);
57   }
58   void IdentifierRead(serialization::IdentID ID,
59                       IdentifierInfo *II) override {
60     if (Previous)
61       Previous->IdentifierRead(ID, II);
62   }
63   void TypeRead(serialization::TypeIdx Idx, QualType T) override {
64     if (Previous)
65       Previous->TypeRead(Idx, T);
66   }
67   void DeclRead(serialization::DeclID ID, const Decl *D) override {
68     if (Previous)
69       Previous->DeclRead(ID, D);
70   }
71   void SelectorRead(serialization::SelectorID ID, Selector Sel) override {
72     if (Previous)
73       Previous->SelectorRead(ID, Sel);
74   }
75   void MacroDefinitionRead(serialization::PreprocessedEntityID PPID,
76                            MacroDefinitionRecord *MD) override {
77     if (Previous)
78       Previous->MacroDefinitionRead(PPID, MD);
79   }
80 };
81 
82 /// \brief Dumps deserialized declarations.
83 class DeserializedDeclsDumper : public DelegatingDeserializationListener {
84 public:
85   explicit DeserializedDeclsDumper(ASTDeserializationListener *Previous,
86                                    bool DeletePrevious)
87       : DelegatingDeserializationListener(Previous, DeletePrevious) {}
88 
89   void DeclRead(serialization::DeclID ID, const Decl *D) override {
90     llvm::outs() << "PCH DECL: " << D->getDeclKindName();
91     if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
92       llvm::outs() << " - " << *ND;
93     llvm::outs() << "\n";
94 
95     DelegatingDeserializationListener::DeclRead(ID, D);
96   }
97 };
98 
99 /// \brief Checks deserialized declarations and emits error if a name
100 /// matches one given in command-line using -error-on-deserialized-decl.
101 class DeserializedDeclsChecker : public DelegatingDeserializationListener {
102   ASTContext &Ctx;
103   std::set<std::string> NamesToCheck;
104 
105 public:
106   DeserializedDeclsChecker(ASTContext &Ctx,
107                            const std::set<std::string> &NamesToCheck,
108                            ASTDeserializationListener *Previous,
109                            bool DeletePrevious)
110       : DelegatingDeserializationListener(Previous, DeletePrevious), Ctx(Ctx),
111         NamesToCheck(NamesToCheck) {}
112 
113   void DeclRead(serialization::DeclID ID, const Decl *D) override {
114     if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
115       if (NamesToCheck.find(ND->getNameAsString()) != NamesToCheck.end()) {
116         unsigned DiagID
117           = Ctx.getDiagnostics().getCustomDiagID(DiagnosticsEngine::Error,
118                                                  "%0 was deserialized");
119         Ctx.getDiagnostics().Report(Ctx.getFullLoc(D->getLocation()), DiagID)
120             << ND->getNameAsString();
121       }
122 
123     DelegatingDeserializationListener::DeclRead(ID, D);
124   }
125 };
126 
127 } // end anonymous namespace
128 
129 FrontendAction::FrontendAction() : Instance(nullptr) {}
130 
131 FrontendAction::~FrontendAction() {}
132 
133 void FrontendAction::setCurrentInput(const FrontendInputFile &CurrentInput,
134                                      std::unique_ptr<ASTUnit> AST) {
135   this->CurrentInput = CurrentInput;
136   CurrentASTUnit = std::move(AST);
137 }
138 
139 std::unique_ptr<ASTConsumer>
140 FrontendAction::CreateWrappedASTConsumer(CompilerInstance &CI,
141                                          StringRef InFile) {
142   std::unique_ptr<ASTConsumer> Consumer = CreateASTConsumer(CI, InFile);
143   if (!Consumer)
144     return nullptr;
145 
146   // If there are no registered plugins we don't need to wrap the consumer
147   if (FrontendPluginRegistry::begin() == FrontendPluginRegistry::end())
148     return Consumer;
149 
150   // Collect the list of plugins that go before the main action (in Consumers)
151   // or after it (in AfterConsumers)
152   std::vector<std::unique_ptr<ASTConsumer>> Consumers;
153   std::vector<std::unique_ptr<ASTConsumer>> AfterConsumers;
154   for (FrontendPluginRegistry::iterator it = FrontendPluginRegistry::begin(),
155                                         ie = FrontendPluginRegistry::end();
156        it != ie; ++it) {
157     std::unique_ptr<PluginASTAction> P = it->instantiate();
158     PluginASTAction::ActionType ActionType = P->getActionType();
159     if (ActionType == PluginASTAction::Cmdline) {
160       // This is O(|plugins| * |add_plugins|), but since both numbers are
161       // way below 50 in practice, that's ok.
162       for (size_t i = 0, e = CI.getFrontendOpts().AddPluginActions.size();
163            i != e; ++i) {
164         if (it->getName() == CI.getFrontendOpts().AddPluginActions[i]) {
165           ActionType = PluginASTAction::AddAfterMainAction;
166           break;
167         }
168       }
169     }
170     if ((ActionType == PluginASTAction::AddBeforeMainAction ||
171          ActionType == PluginASTAction::AddAfterMainAction) &&
172         P->ParseArgs(CI, CI.getFrontendOpts().PluginArgs[it->getName()])) {
173       std::unique_ptr<ASTConsumer> PluginConsumer = P->CreateASTConsumer(CI, InFile);
174       if (ActionType == PluginASTAction::AddBeforeMainAction) {
175         Consumers.push_back(std::move(PluginConsumer));
176       } else {
177         AfterConsumers.push_back(std::move(PluginConsumer));
178       }
179     }
180   }
181 
182   // Add to Consumers the main consumer, then all the plugins that go after it
183   Consumers.push_back(std::move(Consumer));
184   for (auto &C : AfterConsumers) {
185     Consumers.push_back(std::move(C));
186   }
187 
188   return llvm::make_unique<MultiplexConsumer>(std::move(Consumers));
189 }
190 
191 // For preprocessed files, if the first line is the linemarker and specifies
192 // the original source file name, use that name as the input file name.
193 static bool ReadOriginalFileName(CompilerInstance &CI, std::string &InputFile)
194 {
195   bool Invalid = false;
196   auto &SourceMgr = CI.getSourceManager();
197   auto MainFileID = SourceMgr.getMainFileID();
198   const auto *MainFileBuf = SourceMgr.getBuffer(MainFileID, &Invalid);
199   if (Invalid)
200     return false;
201 
202   std::unique_ptr<Lexer> RawLexer(
203       new Lexer(MainFileID, MainFileBuf, SourceMgr, CI.getLangOpts()));
204 
205   // If the first line has the syntax of
206   //
207   // # NUM "FILENAME"
208   //
209   // we use FILENAME as the input file name.
210   Token T;
211   if (RawLexer->LexFromRawLexer(T) || T.getKind() != tok::hash)
212     return false;
213   if (RawLexer->LexFromRawLexer(T) || T.isAtStartOfLine() ||
214       T.getKind() != tok::numeric_constant)
215     return false;
216   RawLexer->LexFromRawLexer(T);
217   if (T.isAtStartOfLine() || T.getKind() != tok::string_literal)
218     return false;
219 
220   StringLiteralParser Literal(T, CI.getPreprocessor());
221   if (Literal.hadError)
222     return false;
223   InputFile = Literal.GetString().str();
224   return true;
225 }
226 
227 bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
228                                      const FrontendInputFile &Input) {
229   assert(!Instance && "Already processing a source file!");
230   assert(!Input.isEmpty() && "Unexpected empty filename!");
231   setCurrentInput(Input);
232   setCompilerInstance(&CI);
233 
234   StringRef InputFile = Input.getFile();
235   bool HasBegunSourceFile = false;
236   if (!BeginInvocation(CI))
237     goto failure;
238 
239   // AST files follow a very different path, since they share objects via the
240   // AST unit.
241   if (Input.getKind() == IK_AST) {
242     assert(!usesPreprocessorOnly() &&
243            "Attempt to pass AST file to preprocessor only action!");
244     assert(hasASTFileSupport() &&
245            "This action does not have AST file support!");
246 
247     IntrusiveRefCntPtr<DiagnosticsEngine> Diags(&CI.getDiagnostics());
248 
249     std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromASTFile(
250         InputFile, CI.getPCHContainerReader(), Diags, CI.getFileSystemOpts(),
251         CI.getCodeGenOpts().DebugTypeExtRefs);
252 
253     if (!AST)
254       goto failure;
255 
256     // Inform the diagnostic client we are processing a source file.
257     CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(), nullptr);
258     HasBegunSourceFile = true;
259 
260     // Set the shared objects, these are reset when we finish processing the
261     // file, otherwise the CompilerInstance will happily destroy them.
262     CI.setFileManager(&AST->getFileManager());
263     CI.setSourceManager(&AST->getSourceManager());
264     CI.setPreprocessor(AST->getPreprocessorPtr());
265     Preprocessor &PP = CI.getPreprocessor();
266     PP.getBuiltinInfo().initializeBuiltins(PP.getIdentifierTable(),
267                                            PP.getLangOpts());
268     CI.setASTContext(&AST->getASTContext());
269 
270     setCurrentInput(Input, std::move(AST));
271 
272     // Initialize the action.
273     if (!BeginSourceFileAction(CI, InputFile))
274       goto failure;
275 
276     // Create the AST consumer.
277     CI.setASTConsumer(CreateWrappedASTConsumer(CI, InputFile));
278     if (!CI.hasASTConsumer())
279       goto failure;
280 
281     return true;
282   }
283 
284   if (!CI.hasVirtualFileSystem()) {
285     if (IntrusiveRefCntPtr<vfs::FileSystem> VFS =
286           createVFSFromCompilerInvocation(CI.getInvocation(),
287                                           CI.getDiagnostics()))
288       CI.setVirtualFileSystem(VFS);
289     else
290       goto failure;
291   }
292 
293   // Set up the file and source managers, if needed.
294   if (!CI.hasFileManager())
295     CI.createFileManager();
296   if (!CI.hasSourceManager())
297     CI.createSourceManager(CI.getFileManager());
298 
299   // IR files bypass the rest of initialization.
300   if (Input.getKind() == IK_LLVM_IR) {
301     assert(hasIRSupport() &&
302            "This action does not have IR file support!");
303 
304     // Inform the diagnostic client we are processing a source file.
305     CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(), nullptr);
306     HasBegunSourceFile = true;
307 
308     // Initialize the action.
309     if (!BeginSourceFileAction(CI, InputFile))
310       goto failure;
311 
312     // Initialize the main file entry.
313     if (!CI.InitializeSourceManager(CurrentInput))
314       goto failure;
315 
316     return true;
317   }
318 
319   // If the implicit PCH include is actually a directory, rather than
320   // a single file, search for a suitable PCH file in that directory.
321   if (!CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
322     FileManager &FileMgr = CI.getFileManager();
323     PreprocessorOptions &PPOpts = CI.getPreprocessorOpts();
324     StringRef PCHInclude = PPOpts.ImplicitPCHInclude;
325     std::string SpecificModuleCachePath = CI.getSpecificModuleCachePath();
326     if (const DirectoryEntry *PCHDir = FileMgr.getDirectory(PCHInclude)) {
327       std::error_code EC;
328       SmallString<128> DirNative;
329       llvm::sys::path::native(PCHDir->getName(), DirNative);
330       bool Found = false;
331       vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
332       for (vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC), DirEnd;
333            Dir != DirEnd && !EC; Dir.increment(EC)) {
334         // Check whether this is an acceptable AST file.
335         if (ASTReader::isAcceptableASTFile(
336                 Dir->getName(), FileMgr, CI.getPCHContainerReader(),
337                 CI.getLangOpts(), CI.getTargetOpts(), CI.getPreprocessorOpts(),
338                 SpecificModuleCachePath)) {
339           PPOpts.ImplicitPCHInclude = Dir->getName();
340           Found = true;
341           break;
342         }
343       }
344 
345       if (!Found) {
346         CI.getDiagnostics().Report(diag::err_fe_no_pch_in_dir) << PCHInclude;
347         goto failure;
348       }
349     }
350   }
351 
352   // Set up the preprocessor if needed. When parsing model files the
353   // preprocessor of the original source is reused.
354   if (!isModelParsingAction())
355     CI.createPreprocessor(getTranslationUnitKind());
356 
357   // Inform the diagnostic client we are processing a source file.
358   CI.getDiagnosticClient().BeginSourceFile(CI.getLangOpts(),
359                                            &CI.getPreprocessor());
360   HasBegunSourceFile = true;
361 
362   // Initialize the action.
363   if (!BeginSourceFileAction(CI, InputFile))
364     goto failure;
365 
366   // Initialize the main file entry. It is important that this occurs after
367   // BeginSourceFileAction, which may change CurrentInput during module builds.
368   if (!CI.InitializeSourceManager(CurrentInput))
369     goto failure;
370 
371   // Create the AST context and consumer unless this is a preprocessor only
372   // action.
373   if (!usesPreprocessorOnly()) {
374     // Parsing a model file should reuse the existing ASTContext.
375     if (!isModelParsingAction())
376       CI.createASTContext();
377 
378     // For preprocessed files, check if the first line specifies the original
379     // source file name with a linemarker.
380     std::string OrigFile;
381     if (Input.isPreprocessed())
382       if (ReadOriginalFileName(CI, OrigFile))
383         InputFile = OrigFile;
384 
385     std::unique_ptr<ASTConsumer> Consumer =
386         CreateWrappedASTConsumer(CI, InputFile);
387     if (!Consumer)
388       goto failure;
389 
390     // FIXME: should not overwrite ASTMutationListener when parsing model files?
391     if (!isModelParsingAction())
392       CI.getASTContext().setASTMutationListener(Consumer->GetASTMutationListener());
393 
394     if (!CI.getPreprocessorOpts().ChainedIncludes.empty()) {
395       // Convert headers to PCH and chain them.
396       IntrusiveRefCntPtr<ExternalSemaSource> source, FinalReader;
397       source = createChainedIncludesSource(CI, FinalReader);
398       if (!source)
399         goto failure;
400       CI.setModuleManager(static_cast<ASTReader *>(FinalReader.get()));
401       CI.getASTContext().setExternalSource(source);
402     } else if (CI.getLangOpts().Modules ||
403                !CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
404       // Use PCM or PCH.
405       assert(hasPCHSupport() && "This action does not have PCH support!");
406       ASTDeserializationListener *DeserialListener =
407           Consumer->GetASTDeserializationListener();
408       bool DeleteDeserialListener = false;
409       if (CI.getPreprocessorOpts().DumpDeserializedPCHDecls) {
410         DeserialListener = new DeserializedDeclsDumper(DeserialListener,
411                                                        DeleteDeserialListener);
412         DeleteDeserialListener = true;
413       }
414       if (!CI.getPreprocessorOpts().DeserializedPCHDeclsToErrorOn.empty()) {
415         DeserialListener = new DeserializedDeclsChecker(
416             CI.getASTContext(),
417             CI.getPreprocessorOpts().DeserializedPCHDeclsToErrorOn,
418             DeserialListener, DeleteDeserialListener);
419         DeleteDeserialListener = true;
420       }
421       if (!CI.getPreprocessorOpts().ImplicitPCHInclude.empty()) {
422         CI.createPCHExternalASTSource(
423             CI.getPreprocessorOpts().ImplicitPCHInclude,
424             CI.getPreprocessorOpts().DisablePCHValidation,
425           CI.getPreprocessorOpts().AllowPCHWithCompilerErrors, DeserialListener,
426             DeleteDeserialListener);
427         if (!CI.getASTContext().getExternalSource())
428           goto failure;
429       }
430       // If modules are enabled, create the module manager before creating
431       // any builtins, so that all declarations know that they might be
432       // extended by an external source.
433       if (CI.getLangOpts().Modules || !CI.hasASTContext() ||
434           !CI.getASTContext().getExternalSource()) {
435         CI.createModuleManager();
436         CI.getModuleManager()->setDeserializationListener(DeserialListener,
437                                                         DeleteDeserialListener);
438       }
439     }
440 
441     CI.setASTConsumer(std::move(Consumer));
442     if (!CI.hasASTConsumer())
443       goto failure;
444   }
445 
446   // Initialize built-in info as long as we aren't using an external AST
447   // source.
448   if (CI.getLangOpts().Modules || !CI.hasASTContext() ||
449       !CI.getASTContext().getExternalSource()) {
450     Preprocessor &PP = CI.getPreprocessor();
451     PP.getBuiltinInfo().initializeBuiltins(PP.getIdentifierTable(),
452                                            PP.getLangOpts());
453   } else {
454     // FIXME: If this is a problem, recover from it by creating a multiplex
455     // source.
456     assert((!CI.getLangOpts().Modules || CI.getModuleManager()) &&
457            "modules enabled but created an external source that "
458            "doesn't support modules");
459   }
460 
461   // If we were asked to load any module map files, do so now.
462   for (const auto &Filename : CI.getFrontendOpts().ModuleMapFiles) {
463     if (auto *File = CI.getFileManager().getFile(Filename))
464       CI.getPreprocessor().getHeaderSearchInfo().loadModuleMapFile(
465           File, /*IsSystem*/false);
466     else
467       CI.getDiagnostics().Report(diag::err_module_map_not_found) << Filename;
468   }
469 
470   // If we were asked to load any module files, do so now.
471   for (const auto &ModuleFile : CI.getFrontendOpts().ModuleFiles)
472     if (!CI.loadModuleFile(ModuleFile))
473       goto failure;
474 
475   // If there is a layout overrides file, attach an external AST source that
476   // provides the layouts from that file.
477   if (!CI.getFrontendOpts().OverrideRecordLayoutsFile.empty() &&
478       CI.hasASTContext() && !CI.getASTContext().getExternalSource()) {
479     IntrusiveRefCntPtr<ExternalASTSource>
480       Override(new LayoutOverrideSource(
481                      CI.getFrontendOpts().OverrideRecordLayoutsFile));
482     CI.getASTContext().setExternalSource(Override);
483   }
484 
485   return true;
486 
487   // If we failed, reset state since the client will not end up calling the
488   // matching EndSourceFile().
489   failure:
490   if (isCurrentFileAST()) {
491     CI.setASTContext(nullptr);
492     CI.setPreprocessor(nullptr);
493     CI.setSourceManager(nullptr);
494     CI.setFileManager(nullptr);
495   }
496 
497   if (HasBegunSourceFile)
498     CI.getDiagnosticClient().EndSourceFile();
499   CI.clearOutputFiles(/*EraseFiles=*/true);
500   setCurrentInput(FrontendInputFile());
501   setCompilerInstance(nullptr);
502   return false;
503 }
504 
505 bool FrontendAction::Execute() {
506   CompilerInstance &CI = getCompilerInstance();
507 
508   if (CI.hasFrontendTimer()) {
509     llvm::TimeRegion Timer(CI.getFrontendTimer());
510     ExecuteAction();
511   }
512   else ExecuteAction();
513 
514   // If we are supposed to rebuild the global module index, do so now unless
515   // there were any module-build failures.
516   if (CI.shouldBuildGlobalModuleIndex() && CI.hasFileManager() &&
517       CI.hasPreprocessor()) {
518     StringRef Cache =
519         CI.getPreprocessor().getHeaderSearchInfo().getModuleCachePath();
520     if (!Cache.empty())
521       GlobalModuleIndex::writeIndex(CI.getFileManager(),
522                                     CI.getPCHContainerReader(), Cache);
523   }
524 
525   return true;
526 }
527 
528 void FrontendAction::EndSourceFile() {
529   CompilerInstance &CI = getCompilerInstance();
530 
531   // Inform the diagnostic client we are done with this source file.
532   CI.getDiagnosticClient().EndSourceFile();
533 
534   // Inform the preprocessor we are done.
535   if (CI.hasPreprocessor())
536     CI.getPreprocessor().EndSourceFile();
537 
538   // Finalize the action.
539   EndSourceFileAction();
540 
541   // Sema references the ast consumer, so reset sema first.
542   //
543   // FIXME: There is more per-file stuff we could just drop here?
544   bool DisableFree = CI.getFrontendOpts().DisableFree;
545   if (DisableFree) {
546     CI.resetAndLeakSema();
547     CI.resetAndLeakASTContext();
548     BuryPointer(CI.takeASTConsumer().get());
549   } else {
550     CI.setSema(nullptr);
551     CI.setASTContext(nullptr);
552     CI.setASTConsumer(nullptr);
553   }
554 
555   if (CI.getFrontendOpts().ShowStats) {
556     llvm::errs() << "\nSTATISTICS FOR '" << getCurrentFile() << "':\n";
557     CI.getPreprocessor().PrintStats();
558     CI.getPreprocessor().getIdentifierTable().PrintStats();
559     CI.getPreprocessor().getHeaderSearchInfo().PrintStats();
560     CI.getSourceManager().PrintStats();
561     llvm::errs() << "\n";
562   }
563 
564   // Cleanup the output streams, and erase the output files if instructed by the
565   // FrontendAction.
566   CI.clearOutputFiles(/*EraseFiles=*/shouldEraseOutputFiles());
567 
568   if (isCurrentFileAST()) {
569     if (DisableFree) {
570       CI.resetAndLeakPreprocessor();
571       CI.resetAndLeakSourceManager();
572       CI.resetAndLeakFileManager();
573     } else {
574       CI.setPreprocessor(nullptr);
575       CI.setSourceManager(nullptr);
576       CI.setFileManager(nullptr);
577     }
578   }
579 
580   setCompilerInstance(nullptr);
581   setCurrentInput(FrontendInputFile());
582 }
583 
584 bool FrontendAction::shouldEraseOutputFiles() {
585   return getCompilerInstance().getDiagnostics().hasErrorOccurred();
586 }
587 
588 //===----------------------------------------------------------------------===//
589 // Utility Actions
590 //===----------------------------------------------------------------------===//
591 
592 void ASTFrontendAction::ExecuteAction() {
593   CompilerInstance &CI = getCompilerInstance();
594   if (!CI.hasPreprocessor())
595     return;
596 
597   // FIXME: Move the truncation aspect of this into Sema, we delayed this till
598   // here so the source manager would be initialized.
599   if (hasCodeCompletionSupport() &&
600       !CI.getFrontendOpts().CodeCompletionAt.FileName.empty())
601     CI.createCodeCompletionConsumer();
602 
603   // Use a code completion consumer?
604   CodeCompleteConsumer *CompletionConsumer = nullptr;
605   if (CI.hasCodeCompletionConsumer())
606     CompletionConsumer = &CI.getCodeCompletionConsumer();
607 
608   if (!CI.hasSema())
609     CI.createSema(getTranslationUnitKind(), CompletionConsumer);
610 
611   ParseAST(CI.getSema(), CI.getFrontendOpts().ShowStats,
612            CI.getFrontendOpts().SkipFunctionBodies);
613 }
614 
615 void PluginASTAction::anchor() { }
616 
617 std::unique_ptr<ASTConsumer>
618 PreprocessorFrontendAction::CreateASTConsumer(CompilerInstance &CI,
619                                               StringRef InFile) {
620   llvm_unreachable("Invalid CreateASTConsumer on preprocessor action!");
621 }
622 
623 std::unique_ptr<ASTConsumer>
624 WrapperFrontendAction::CreateASTConsumer(CompilerInstance &CI,
625                                          StringRef InFile) {
626   return WrappedAction->CreateASTConsumer(CI, InFile);
627 }
628 bool WrapperFrontendAction::BeginInvocation(CompilerInstance &CI) {
629   return WrappedAction->BeginInvocation(CI);
630 }
631 bool WrapperFrontendAction::BeginSourceFileAction(CompilerInstance &CI,
632                                                   StringRef Filename) {
633   WrappedAction->setCurrentInput(getCurrentInput());
634   WrappedAction->setCompilerInstance(&CI);
635   auto Ret = WrappedAction->BeginSourceFileAction(CI, Filename);
636   // BeginSourceFileAction may change CurrentInput, e.g. during module builds.
637   setCurrentInput(WrappedAction->getCurrentInput());
638   return Ret;
639 }
640 void WrapperFrontendAction::ExecuteAction() {
641   WrappedAction->ExecuteAction();
642 }
643 void WrapperFrontendAction::EndSourceFileAction() {
644   WrappedAction->EndSourceFileAction();
645 }
646 
647 bool WrapperFrontendAction::usesPreprocessorOnly() const {
648   return WrappedAction->usesPreprocessorOnly();
649 }
650 TranslationUnitKind WrapperFrontendAction::getTranslationUnitKind() {
651   return WrappedAction->getTranslationUnitKind();
652 }
653 bool WrapperFrontendAction::hasPCHSupport() const {
654   return WrappedAction->hasPCHSupport();
655 }
656 bool WrapperFrontendAction::hasASTFileSupport() const {
657   return WrappedAction->hasASTFileSupport();
658 }
659 bool WrapperFrontendAction::hasIRSupport() const {
660   return WrappedAction->hasIRSupport();
661 }
662 bool WrapperFrontendAction::hasCodeCompletionSupport() const {
663   return WrappedAction->hasCodeCompletionSupport();
664 }
665 
666 WrapperFrontendAction::WrapperFrontendAction(
667     std::unique_ptr<FrontendAction> WrappedAction)
668   : WrappedAction(std::move(WrappedAction)) {}
669 
670