xref: /llvm-project/clang/lib/Frontend/CompilerInstance.cpp (revision 899292827456532bc66219f9d778595c57614f77)
1 //===--- CompilerInstance.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/CompilerInstance.h"
11 #include "clang/Sema/Sema.h"
12 #include "clang/AST/ASTConsumer.h"
13 #include "clang/AST/ASTContext.h"
14 #include "clang/AST/Decl.h"
15 #include "clang/Basic/Diagnostic.h"
16 #include "clang/Basic/FileManager.h"
17 #include "clang/Basic/SourceManager.h"
18 #include "clang/Basic/TargetInfo.h"
19 #include "clang/Basic/Version.h"
20 #include "clang/Lex/HeaderSearch.h"
21 #include "clang/Lex/Preprocessor.h"
22 #include "clang/Lex/PTHManager.h"
23 #include "clang/Frontend/ChainedDiagnosticConsumer.h"
24 #include "clang/Frontend/FrontendAction.h"
25 #include "clang/Frontend/FrontendActions.h"
26 #include "clang/Frontend/FrontendDiagnostic.h"
27 #include "clang/Frontend/LogDiagnosticPrinter.h"
28 #include "clang/Frontend/SerializedDiagnosticPrinter.h"
29 #include "clang/Frontend/TextDiagnosticPrinter.h"
30 #include "clang/Frontend/VerifyDiagnosticConsumer.h"
31 #include "clang/Frontend/Utils.h"
32 #include "clang/Serialization/ASTReader.h"
33 #include "clang/Sema/CodeCompleteConsumer.h"
34 #include "llvm/Support/FileSystem.h"
35 #include "llvm/Support/MemoryBuffer.h"
36 #include "llvm/Support/raw_ostream.h"
37 #include "llvm/ADT/Statistic.h"
38 #include "llvm/Support/Timer.h"
39 #include "llvm/Support/Host.h"
40 #include "llvm/Support/LockFileManager.h"
41 #include "llvm/Support/Path.h"
42 #include "llvm/Support/Program.h"
43 #include "llvm/Support/Signals.h"
44 #include "llvm/Support/system_error.h"
45 #include "llvm/Support/CrashRecoveryContext.h"
46 #include "llvm/Config/config.h"
47 
48 using namespace clang;
49 
50 CompilerInstance::CompilerInstance()
51   : Invocation(new CompilerInvocation()), ModuleManager(0) {
52 }
53 
54 CompilerInstance::~CompilerInstance() {
55 }
56 
57 void CompilerInstance::setInvocation(CompilerInvocation *Value) {
58   Invocation = Value;
59 }
60 
61 void CompilerInstance::setDiagnostics(DiagnosticsEngine *Value) {
62   Diagnostics = Value;
63 }
64 
65 void CompilerInstance::setTarget(TargetInfo *Value) {
66   Target = Value;
67 }
68 
69 void CompilerInstance::setFileManager(FileManager *Value) {
70   FileMgr = Value;
71 }
72 
73 void CompilerInstance::setSourceManager(SourceManager *Value) {
74   SourceMgr = Value;
75 }
76 
77 void CompilerInstance::setPreprocessor(Preprocessor *Value) { PP = Value; }
78 
79 void CompilerInstance::setASTContext(ASTContext *Value) { Context = Value; }
80 
81 void CompilerInstance::setSema(Sema *S) {
82   TheSema.reset(S);
83 }
84 
85 void CompilerInstance::setASTConsumer(ASTConsumer *Value) {
86   Consumer.reset(Value);
87 }
88 
89 void CompilerInstance::setCodeCompletionConsumer(CodeCompleteConsumer *Value) {
90   CompletionConsumer.reset(Value);
91 }
92 
93 // Diagnostics
94 static void SetUpBuildDumpLog(const DiagnosticOptions &DiagOpts,
95                               unsigned argc, const char* const *argv,
96                               DiagnosticsEngine &Diags) {
97   std::string ErrorInfo;
98   llvm::OwningPtr<raw_ostream> OS(
99     new llvm::raw_fd_ostream(DiagOpts.DumpBuildInformation.c_str(), ErrorInfo));
100   if (!ErrorInfo.empty()) {
101     Diags.Report(diag::err_fe_unable_to_open_logfile)
102                  << DiagOpts.DumpBuildInformation << ErrorInfo;
103     return;
104   }
105 
106   (*OS) << "clang -cc1 command line arguments: ";
107   for (unsigned i = 0; i != argc; ++i)
108     (*OS) << argv[i] << ' ';
109   (*OS) << '\n';
110 
111   // Chain in a diagnostic client which will log the diagnostics.
112   DiagnosticConsumer *Logger =
113     new TextDiagnosticPrinter(*OS.take(), DiagOpts, /*OwnsOutputStream=*/true);
114   Diags.setClient(new ChainedDiagnosticConsumer(Diags.takeClient(), Logger));
115 }
116 
117 static void SetUpDiagnosticLog(const DiagnosticOptions &DiagOpts,
118                                const CodeGenOptions *CodeGenOpts,
119                                DiagnosticsEngine &Diags) {
120   std::string ErrorInfo;
121   bool OwnsStream = false;
122   raw_ostream *OS = &llvm::errs();
123   if (DiagOpts.DiagnosticLogFile != "-") {
124     // Create the output stream.
125     llvm::raw_fd_ostream *FileOS(
126       new llvm::raw_fd_ostream(DiagOpts.DiagnosticLogFile.c_str(),
127                                ErrorInfo, llvm::raw_fd_ostream::F_Append));
128     if (!ErrorInfo.empty()) {
129       Diags.Report(diag::warn_fe_cc_log_diagnostics_failure)
130         << DiagOpts.DumpBuildInformation << ErrorInfo;
131     } else {
132       FileOS->SetUnbuffered();
133       FileOS->SetUseAtomicWrites(true);
134       OS = FileOS;
135       OwnsStream = true;
136     }
137   }
138 
139   // Chain in the diagnostic client which will log the diagnostics.
140   LogDiagnosticPrinter *Logger = new LogDiagnosticPrinter(*OS, DiagOpts,
141                                                           OwnsStream);
142   if (CodeGenOpts)
143     Logger->setDwarfDebugFlags(CodeGenOpts->DwarfDebugFlags);
144   Diags.setClient(new ChainedDiagnosticConsumer(Diags.takeClient(), Logger));
145 }
146 
147 static void SetupSerializedDiagnostics(const DiagnosticOptions &DiagOpts,
148                                        DiagnosticsEngine &Diags,
149                                        StringRef OutputFile) {
150   std::string ErrorInfo;
151   llvm::OwningPtr<llvm::raw_fd_ostream> OS;
152   OS.reset(new llvm::raw_fd_ostream(OutputFile.str().c_str(), ErrorInfo,
153                                     llvm::raw_fd_ostream::F_Binary));
154 
155   if (!ErrorInfo.empty()) {
156     Diags.Report(diag::warn_fe_serialized_diag_failure)
157       << OutputFile << ErrorInfo;
158     return;
159   }
160 
161   DiagnosticConsumer *SerializedConsumer =
162     clang::serialized_diags::create(OS.take(), DiagOpts);
163 
164 
165   Diags.setClient(new ChainedDiagnosticConsumer(Diags.takeClient(),
166                                                 SerializedConsumer));
167 }
168 
169 void CompilerInstance::createDiagnostics(int Argc, const char* const *Argv,
170                                          DiagnosticConsumer *Client,
171                                          bool ShouldOwnClient,
172                                          bool ShouldCloneClient) {
173   Diagnostics = createDiagnostics(getDiagnosticOpts(), Argc, Argv, Client,
174                                   ShouldOwnClient, ShouldCloneClient,
175                                   &getCodeGenOpts());
176 }
177 
178 llvm::IntrusiveRefCntPtr<DiagnosticsEngine>
179 CompilerInstance::createDiagnostics(const DiagnosticOptions &Opts,
180                                     int Argc, const char* const *Argv,
181                                     DiagnosticConsumer *Client,
182                                     bool ShouldOwnClient,
183                                     bool ShouldCloneClient,
184                                     const CodeGenOptions *CodeGenOpts) {
185   llvm::IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
186   llvm::IntrusiveRefCntPtr<DiagnosticsEngine>
187       Diags(new DiagnosticsEngine(DiagID));
188 
189   // Create the diagnostic client for reporting errors or for
190   // implementing -verify.
191   if (Client) {
192     if (ShouldCloneClient)
193       Diags->setClient(Client->clone(*Diags), ShouldOwnClient);
194     else
195       Diags->setClient(Client, ShouldOwnClient);
196   } else
197     Diags->setClient(new TextDiagnosticPrinter(llvm::errs(), Opts));
198 
199   // Chain in -verify checker, if requested.
200   if (Opts.VerifyDiagnostics)
201     Diags->setClient(new VerifyDiagnosticConsumer(*Diags));
202 
203   // Chain in -diagnostic-log-file dumper, if requested.
204   if (!Opts.DiagnosticLogFile.empty())
205     SetUpDiagnosticLog(Opts, CodeGenOpts, *Diags);
206 
207   if (!Opts.DumpBuildInformation.empty())
208     SetUpBuildDumpLog(Opts, Argc, Argv, *Diags);
209 
210   if (!Opts.DiagnosticSerializationFile.empty())
211     SetupSerializedDiagnostics(Opts, *Diags,
212                                Opts.DiagnosticSerializationFile);
213 
214   // Configure our handling of diagnostics.
215   ProcessWarningOptions(*Diags, Opts);
216 
217   return Diags;
218 }
219 
220 // File Manager
221 
222 void CompilerInstance::createFileManager() {
223   FileMgr = new FileManager(getFileSystemOpts());
224 }
225 
226 // Source Manager
227 
228 void CompilerInstance::createSourceManager(FileManager &FileMgr) {
229   SourceMgr = new SourceManager(getDiagnostics(), FileMgr);
230 }
231 
232 // Preprocessor
233 
234 void CompilerInstance::createPreprocessor() {
235   const PreprocessorOptions &PPOpts = getPreprocessorOpts();
236 
237   // Create a PTH manager if we are using some form of a token cache.
238   PTHManager *PTHMgr = 0;
239   if (!PPOpts.TokenCache.empty())
240     PTHMgr = PTHManager::Create(PPOpts.TokenCache, getDiagnostics());
241 
242   // Create the Preprocessor.
243   HeaderSearch *HeaderInfo = new HeaderSearch(getFileManager(),
244                                               getDiagnostics(),
245                                               getLangOpts(),
246                                               &getTarget());
247   PP = new Preprocessor(getDiagnostics(), getLangOpts(), &getTarget(),
248                         getSourceManager(), *HeaderInfo, *this, PTHMgr,
249                         /*OwnsHeaderSearch=*/true);
250 
251   // Note that this is different then passing PTHMgr to Preprocessor's ctor.
252   // That argument is used as the IdentifierInfoLookup argument to
253   // IdentifierTable's ctor.
254   if (PTHMgr) {
255     PTHMgr->setPreprocessor(&*PP);
256     PP->setPTHManager(PTHMgr);
257   }
258 
259   if (PPOpts.DetailedRecord)
260     PP->createPreprocessingRecord(
261                                   PPOpts.DetailedRecordIncludesNestedMacroExpansions);
262 
263   InitializePreprocessor(*PP, PPOpts, getHeaderSearchOpts(), getFrontendOpts());
264 
265   // Set up the module path, including the hash for the
266   // module-creation options.
267   llvm::SmallString<256> SpecificModuleCache(
268                            getHeaderSearchOpts().ModuleCachePath);
269   if (!getHeaderSearchOpts().DisableModuleHash)
270     llvm::sys::path::append(SpecificModuleCache,
271                             getInvocation().getModuleHash());
272   PP->getHeaderSearchInfo().setModuleCachePath(SpecificModuleCache);
273 
274   // Handle generating dependencies, if requested.
275   const DependencyOutputOptions &DepOpts = getDependencyOutputOpts();
276   if (!DepOpts.OutputFile.empty())
277     AttachDependencyFileGen(*PP, DepOpts);
278 
279   // Handle generating header include information, if requested.
280   if (DepOpts.ShowHeaderIncludes)
281     AttachHeaderIncludeGen(*PP);
282   if (!DepOpts.HeaderIncludeOutputFile.empty()) {
283     StringRef OutputPath = DepOpts.HeaderIncludeOutputFile;
284     if (OutputPath == "-")
285       OutputPath = "";
286     AttachHeaderIncludeGen(*PP, /*ShowAllHeaders=*/true, OutputPath,
287                            /*ShowDepth=*/false);
288   }
289 }
290 
291 // ASTContext
292 
293 void CompilerInstance::createASTContext() {
294   Preprocessor &PP = getPreprocessor();
295   Context = new ASTContext(getLangOpts(), PP.getSourceManager(),
296                            &getTarget(), PP.getIdentifierTable(),
297                            PP.getSelectorTable(), PP.getBuiltinInfo(),
298                            /*size_reserve=*/ 0);
299 }
300 
301 // ExternalASTSource
302 
303 void CompilerInstance::createPCHExternalASTSource(StringRef Path,
304                                                   bool DisablePCHValidation,
305                                                   bool DisableStatCache,
306                                                  void *DeserializationListener){
307   llvm::OwningPtr<ExternalASTSource> Source;
308   bool Preamble = getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
309   Source.reset(createPCHExternalASTSource(Path, getHeaderSearchOpts().Sysroot,
310                                           DisablePCHValidation,
311                                           DisableStatCache,
312                                           getPreprocessor(), getASTContext(),
313                                           DeserializationListener,
314                                           Preamble));
315   ModuleManager = static_cast<ASTReader*>(Source.get());
316   getASTContext().setExternalSource(Source);
317 }
318 
319 ExternalASTSource *
320 CompilerInstance::createPCHExternalASTSource(StringRef Path,
321                                              const std::string &Sysroot,
322                                              bool DisablePCHValidation,
323                                              bool DisableStatCache,
324                                              Preprocessor &PP,
325                                              ASTContext &Context,
326                                              void *DeserializationListener,
327                                              bool Preamble) {
328   llvm::OwningPtr<ASTReader> Reader;
329   Reader.reset(new ASTReader(PP, Context,
330                              Sysroot.empty() ? "" : Sysroot.c_str(),
331                              DisablePCHValidation, DisableStatCache));
332 
333   Reader->setDeserializationListener(
334             static_cast<ASTDeserializationListener *>(DeserializationListener));
335   switch (Reader->ReadAST(Path,
336                           Preamble ? serialization::MK_Preamble
337                                    : serialization::MK_PCH)) {
338   case ASTReader::Success:
339     // Set the predefines buffer as suggested by the PCH reader. Typically, the
340     // predefines buffer will be empty.
341     PP.setPredefines(Reader->getSuggestedPredefines());
342     return Reader.take();
343 
344   case ASTReader::Failure:
345     // Unrecoverable failure: don't even try to process the input file.
346     break;
347 
348   case ASTReader::IgnorePCH:
349     // No suitable PCH file could be found. Return an error.
350     break;
351   }
352 
353   return 0;
354 }
355 
356 // Code Completion
357 
358 static bool EnableCodeCompletion(Preprocessor &PP,
359                                  const std::string &Filename,
360                                  unsigned Line,
361                                  unsigned Column) {
362   // Tell the source manager to chop off the given file at a specific
363   // line and column.
364   const FileEntry *Entry = PP.getFileManager().getFile(Filename);
365   if (!Entry) {
366     PP.getDiagnostics().Report(diag::err_fe_invalid_code_complete_file)
367       << Filename;
368     return true;
369   }
370 
371   // Truncate the named file at the given line/column.
372   PP.SetCodeCompletionPoint(Entry, Line, Column);
373   return false;
374 }
375 
376 void CompilerInstance::createCodeCompletionConsumer() {
377   const ParsedSourceLocation &Loc = getFrontendOpts().CodeCompletionAt;
378   if (!CompletionConsumer) {
379     CompletionConsumer.reset(
380       createCodeCompletionConsumer(getPreprocessor(),
381                                    Loc.FileName, Loc.Line, Loc.Column,
382                                    getFrontendOpts().ShowMacrosInCodeCompletion,
383                              getFrontendOpts().ShowCodePatternsInCodeCompletion,
384                            getFrontendOpts().ShowGlobalSymbolsInCodeCompletion,
385                                    llvm::outs()));
386     if (!CompletionConsumer)
387       return;
388   } else if (EnableCodeCompletion(getPreprocessor(), Loc.FileName,
389                                   Loc.Line, Loc.Column)) {
390     CompletionConsumer.reset();
391     return;
392   }
393 
394   if (CompletionConsumer->isOutputBinary() &&
395       llvm::sys::Program::ChangeStdoutToBinary()) {
396     getPreprocessor().getDiagnostics().Report(diag::err_fe_stdout_binary);
397     CompletionConsumer.reset();
398   }
399 }
400 
401 void CompilerInstance::createFrontendTimer() {
402   FrontendTimer.reset(new llvm::Timer("Clang front-end timer"));
403 }
404 
405 CodeCompleteConsumer *
406 CompilerInstance::createCodeCompletionConsumer(Preprocessor &PP,
407                                                const std::string &Filename,
408                                                unsigned Line,
409                                                unsigned Column,
410                                                bool ShowMacros,
411                                                bool ShowCodePatterns,
412                                                bool ShowGlobals,
413                                                raw_ostream &OS) {
414   if (EnableCodeCompletion(PP, Filename, Line, Column))
415     return 0;
416 
417   // Set up the creation routine for code-completion.
418   return new PrintingCodeCompleteConsumer(ShowMacros, ShowCodePatterns,
419                                           ShowGlobals, OS);
420 }
421 
422 void CompilerInstance::createSema(TranslationUnitKind TUKind,
423                                   CodeCompleteConsumer *CompletionConsumer) {
424   TheSema.reset(new Sema(getPreprocessor(), getASTContext(), getASTConsumer(),
425                          TUKind, CompletionConsumer));
426 }
427 
428 // Output Files
429 
430 void CompilerInstance::addOutputFile(const OutputFile &OutFile) {
431   assert(OutFile.OS && "Attempt to add empty stream to output list!");
432   OutputFiles.push_back(OutFile);
433 }
434 
435 void CompilerInstance::clearOutputFiles(bool EraseFiles) {
436   for (std::list<OutputFile>::iterator
437          it = OutputFiles.begin(), ie = OutputFiles.end(); it != ie; ++it) {
438     delete it->OS;
439     if (!it->TempFilename.empty()) {
440       if (EraseFiles) {
441         bool existed;
442         llvm::sys::fs::remove(it->TempFilename, existed);
443       } else {
444         llvm::SmallString<128> NewOutFile(it->Filename);
445 
446         // If '-working-directory' was passed, the output filename should be
447         // relative to that.
448         FileMgr->FixupRelativePath(NewOutFile);
449         if (llvm::error_code ec = llvm::sys::fs::rename(it->TempFilename,
450                                                         NewOutFile.str())) {
451           getDiagnostics().Report(diag::err_fe_unable_to_rename_temp)
452             << it->TempFilename << it->Filename << ec.message();
453 
454           bool existed;
455           llvm::sys::fs::remove(it->TempFilename, existed);
456         }
457       }
458     } else if (!it->Filename.empty() && EraseFiles)
459       llvm::sys::Path(it->Filename).eraseFromDisk();
460 
461   }
462   OutputFiles.clear();
463 }
464 
465 llvm::raw_fd_ostream *
466 CompilerInstance::createDefaultOutputFile(bool Binary,
467                                           StringRef InFile,
468                                           StringRef Extension) {
469   return createOutputFile(getFrontendOpts().OutputFile, Binary,
470                           /*RemoveFileOnSignal=*/true, InFile, Extension);
471 }
472 
473 llvm::raw_fd_ostream *
474 CompilerInstance::createOutputFile(StringRef OutputPath,
475                                    bool Binary, bool RemoveFileOnSignal,
476                                    StringRef InFile,
477                                    StringRef Extension,
478                                    bool UseTemporary) {
479   std::string Error, OutputPathName, TempPathName;
480   llvm::raw_fd_ostream *OS = createOutputFile(OutputPath, Error, Binary,
481                                               RemoveFileOnSignal,
482                                               InFile, Extension,
483                                               UseTemporary,
484                                               &OutputPathName,
485                                               &TempPathName);
486   if (!OS) {
487     getDiagnostics().Report(diag::err_fe_unable_to_open_output)
488       << OutputPath << Error;
489     return 0;
490   }
491 
492   // Add the output file -- but don't try to remove "-", since this means we are
493   // using stdin.
494   addOutputFile(OutputFile((OutputPathName != "-") ? OutputPathName : "",
495                 TempPathName, OS));
496 
497   return OS;
498 }
499 
500 llvm::raw_fd_ostream *
501 CompilerInstance::createOutputFile(StringRef OutputPath,
502                                    std::string &Error,
503                                    bool Binary,
504                                    bool RemoveFileOnSignal,
505                                    StringRef InFile,
506                                    StringRef Extension,
507                                    bool UseTemporary,
508                                    std::string *ResultPathName,
509                                    std::string *TempPathName) {
510   std::string OutFile, TempFile;
511   if (!OutputPath.empty()) {
512     OutFile = OutputPath;
513   } else if (InFile == "-") {
514     OutFile = "-";
515   } else if (!Extension.empty()) {
516     llvm::sys::Path Path(InFile);
517     Path.eraseSuffix();
518     Path.appendSuffix(Extension);
519     OutFile = Path.str();
520   } else {
521     OutFile = "-";
522   }
523 
524   llvm::OwningPtr<llvm::raw_fd_ostream> OS;
525   std::string OSFile;
526 
527   if (UseTemporary && OutFile != "-") {
528     llvm::sys::Path OutPath(OutFile);
529     // Only create the temporary if we can actually write to OutPath, otherwise
530     // we want to fail early.
531     bool Exists;
532     if ((llvm::sys::fs::exists(OutPath.str(), Exists) || !Exists) ||
533         (OutPath.isRegularFile() && OutPath.canWrite())) {
534       // Create a temporary file.
535       llvm::SmallString<128> TempPath;
536       TempPath = OutFile;
537       TempPath += "-%%%%%%%%";
538       int fd;
539       if (llvm::sys::fs::unique_file(TempPath.str(), fd, TempPath,
540                                /*makeAbsolute=*/false) == llvm::errc::success) {
541         OS.reset(new llvm::raw_fd_ostream(fd, /*shouldClose=*/true));
542         OSFile = TempFile = TempPath.str();
543       }
544     }
545   }
546 
547   if (!OS) {
548     OSFile = OutFile;
549     OS.reset(
550       new llvm::raw_fd_ostream(OSFile.c_str(), Error,
551                                (Binary ? llvm::raw_fd_ostream::F_Binary : 0)));
552     if (!Error.empty())
553       return 0;
554   }
555 
556   // Make sure the out stream file gets removed if we crash.
557   if (RemoveFileOnSignal)
558     llvm::sys::RemoveFileOnSignal(llvm::sys::Path(OSFile));
559 
560   if (ResultPathName)
561     *ResultPathName = OutFile;
562   if (TempPathName)
563     *TempPathName = TempFile;
564 
565   return OS.take();
566 }
567 
568 // Initialization Utilities
569 
570 bool CompilerInstance::InitializeSourceManager(StringRef InputFile,
571                                                SrcMgr::CharacteristicKind Kind){
572   return InitializeSourceManager(InputFile, Kind, getDiagnostics(),
573                                  getFileManager(), getSourceManager(),
574                                  getFrontendOpts());
575 }
576 
577 bool CompilerInstance::InitializeSourceManager(StringRef InputFile,
578                                                SrcMgr::CharacteristicKind Kind,
579                                                DiagnosticsEngine &Diags,
580                                                FileManager &FileMgr,
581                                                SourceManager &SourceMgr,
582                                                const FrontendOptions &Opts) {
583   // Figure out where to get and map in the main file.
584   if (InputFile != "-") {
585     const FileEntry *File = FileMgr.getFile(InputFile);
586     if (!File) {
587       Diags.Report(diag::err_fe_error_reading) << InputFile;
588       return false;
589     }
590     SourceMgr.createMainFileID(File, Kind);
591   } else {
592     llvm::OwningPtr<llvm::MemoryBuffer> SB;
593     if (llvm::MemoryBuffer::getSTDIN(SB)) {
594       // FIXME: Give ec.message() in this diag.
595       Diags.Report(diag::err_fe_error_reading_stdin);
596       return false;
597     }
598     const FileEntry *File = FileMgr.getVirtualFile(SB->getBufferIdentifier(),
599                                                    SB->getBufferSize(), 0);
600     SourceMgr.createMainFileID(File, Kind);
601     SourceMgr.overrideFileContents(File, SB.take());
602   }
603 
604   assert(!SourceMgr.getMainFileID().isInvalid() &&
605          "Couldn't establish MainFileID!");
606   return true;
607 }
608 
609 // High-Level Operations
610 
611 bool CompilerInstance::ExecuteAction(FrontendAction &Act) {
612   assert(hasDiagnostics() && "Diagnostics engine is not initialized!");
613   assert(!getFrontendOpts().ShowHelp && "Client must handle '-help'!");
614   assert(!getFrontendOpts().ShowVersion && "Client must handle '-version'!");
615 
616   // FIXME: Take this as an argument, once all the APIs we used have moved to
617   // taking it as an input instead of hard-coding llvm::errs.
618   raw_ostream &OS = llvm::errs();
619 
620   // Create the target instance.
621   setTarget(TargetInfo::CreateTargetInfo(getDiagnostics(), getTargetOpts()));
622   if (!hasTarget())
623     return false;
624 
625   // Inform the target of the language options.
626   //
627   // FIXME: We shouldn't need to do this, the target should be immutable once
628   // created. This complexity should be lifted elsewhere.
629   getTarget().setForcedLangOptions(getLangOpts());
630 
631   // Validate/process some options.
632   if (getHeaderSearchOpts().Verbose)
633     OS << "clang -cc1 version " CLANG_VERSION_STRING
634        << " based upon " << PACKAGE_STRING
635        << " default target " << llvm::sys::getDefaultTargetTriple() << "\n";
636 
637   if (getFrontendOpts().ShowTimers)
638     createFrontendTimer();
639 
640   if (getFrontendOpts().ShowStats)
641     llvm::EnableStatistics();
642 
643   for (unsigned i = 0, e = getFrontendOpts().Inputs.size(); i != e; ++i) {
644     // Reset the ID tables if we are reusing the SourceManager.
645     if (hasSourceManager())
646       getSourceManager().clearIDTables();
647 
648     if (Act.BeginSourceFile(*this, getFrontendOpts().Inputs[i])) {
649       Act.Execute();
650       Act.EndSourceFile();
651     }
652   }
653 
654   // Notify the diagnostic client that all files were processed.
655   getDiagnostics().getClient()->finish();
656 
657   if (getDiagnosticOpts().ShowCarets) {
658     // We can have multiple diagnostics sharing one diagnostic client.
659     // Get the total number of warnings/errors from the client.
660     unsigned NumWarnings = getDiagnostics().getClient()->getNumWarnings();
661     unsigned NumErrors = getDiagnostics().getClient()->getNumErrors();
662 
663     if (NumWarnings)
664       OS << NumWarnings << " warning" << (NumWarnings == 1 ? "" : "s");
665     if (NumWarnings && NumErrors)
666       OS << " and ";
667     if (NumErrors)
668       OS << NumErrors << " error" << (NumErrors == 1 ? "" : "s");
669     if (NumWarnings || NumErrors)
670       OS << " generated.\n";
671   }
672 
673   if (getFrontendOpts().ShowStats && hasFileManager()) {
674     getFileManager().PrintStats();
675     OS << "\n";
676   }
677 
678   return !getDiagnostics().getClient()->getNumErrors();
679 }
680 
681 /// \brief Determine the appropriate source input kind based on language
682 /// options.
683 static InputKind getSourceInputKindFromOptions(const LangOptions &LangOpts) {
684   if (LangOpts.OpenCL)
685     return IK_OpenCL;
686   if (LangOpts.CUDA)
687     return IK_CUDA;
688   if (LangOpts.ObjC1)
689     return LangOpts.CPlusPlus? IK_ObjCXX : IK_ObjC;
690   return LangOpts.CPlusPlus? IK_CXX : IK_C;
691 }
692 
693 namespace {
694   struct CompileModuleMapData {
695     CompilerInstance &Instance;
696     GenerateModuleAction &CreateModuleAction;
697   };
698 }
699 
700 /// \brief Helper function that executes the module-generating action under
701 /// a crash recovery context.
702 static void doCompileMapModule(void *UserData) {
703   CompileModuleMapData &Data
704     = *reinterpret_cast<CompileModuleMapData *>(UserData);
705   Data.Instance.ExecuteAction(Data.CreateModuleAction);
706 }
707 
708 /// \brief Compile a module file for the given module, using the options
709 /// provided by the importing compiler instance.
710 static void compileModule(CompilerInstance &ImportingInstance,
711                           Module *Module,
712                           StringRef ModuleFileName) {
713   llvm::LockFileManager Locked(ModuleFileName);
714   switch (Locked) {
715   case llvm::LockFileManager::LFS_Error:
716     return;
717 
718   case llvm::LockFileManager::LFS_Owned:
719     // We're responsible for building the module ourselves. Do so below.
720     break;
721 
722   case llvm::LockFileManager::LFS_Shared:
723     // Someone else is responsible for building the module. Wait for them to
724     // finish.
725     Locked.waitForUnlock();
726     break;
727   }
728 
729   ModuleMap &ModMap
730     = ImportingInstance.getPreprocessor().getHeaderSearchInfo().getModuleMap();
731 
732   // Construct a compiler invocation for creating this module.
733   llvm::IntrusiveRefCntPtr<CompilerInvocation> Invocation
734     (new CompilerInvocation(ImportingInstance.getInvocation()));
735 
736   PreprocessorOptions &PPOpts = Invocation->getPreprocessorOpts();
737 
738   // For any options that aren't intended to affect how a module is built,
739   // reset them to their default values.
740   Invocation->getLangOpts()->resetNonModularOptions();
741   PPOpts.resetNonModularOptions();
742 
743   // Note the name of the module we're building.
744   Invocation->getLangOpts()->CurrentModule = Module->getTopLevelModuleName();
745 
746   // Note that this module is part of the module build path, so that we
747   // can detect cycles in the module graph.
748   PPOpts.ModuleBuildPath.push_back(Module->getTopLevelModuleName());
749 
750   // If there is a module map file, build the module using the module map.
751   // Set up the inputs/outputs so that we build the module from its umbrella
752   // header.
753   FrontendOptions &FrontendOpts = Invocation->getFrontendOpts();
754   FrontendOpts.OutputFile = ModuleFileName.str();
755   FrontendOpts.DisableFree = false;
756   FrontendOpts.Inputs.clear();
757   InputKind IK = getSourceInputKindFromOptions(*Invocation->getLangOpts());
758 
759   // Get or create the module map that we'll use to build this module.
760   llvm::SmallString<128> TempModuleMapFileName;
761   if (const FileEntry *ModuleMapFile
762                                   = ModMap.getContainingModuleMapFile(Module)) {
763     // Use the module map where this module resides.
764     FrontendOpts.Inputs.push_back(FrontendInputFile(ModuleMapFile->getName(),
765                                                     IK));
766   } else {
767     // Create a temporary module map file.
768     TempModuleMapFileName = Module->Name;
769     TempModuleMapFileName += "-%%%%%%%%.map";
770     int FD;
771     if (llvm::sys::fs::unique_file(TempModuleMapFileName.str(), FD,
772                                    TempModuleMapFileName,
773                                    /*makeAbsolute=*/true)
774           != llvm::errc::success) {
775       ImportingInstance.getDiagnostics().Report(diag::err_module_map_temp_file)
776         << TempModuleMapFileName;
777       return;
778     }
779     // Print the module map to this file.
780     llvm::raw_fd_ostream OS(FD, /*shouldClose=*/true);
781     Module->print(OS);
782     FrontendOpts.Inputs.push_back(
783       FrontendInputFile(TempModuleMapFileName.str().str(), IK));
784   }
785 
786   // Don't free the remapped file buffers; they are owned by our caller.
787   PPOpts.RetainRemappedFileBuffers = true;
788 
789   Invocation->getDiagnosticOpts().VerifyDiagnostics = 0;
790   assert(ImportingInstance.getInvocation().getModuleHash() ==
791          Invocation->getModuleHash() && "Module hash mismatch!");
792 
793   // Construct a compiler instance that will be used to actually create the
794   // module.
795   CompilerInstance Instance;
796   Instance.setInvocation(&*Invocation);
797   Instance.createDiagnostics(/*argc=*/0, /*argv=*/0,
798                              &ImportingInstance.getDiagnosticClient(),
799                              /*ShouldOwnClient=*/true,
800                              /*ShouldCloneClient=*/true);
801 
802   // Construct a module-generating action.
803   GenerateModuleAction CreateModuleAction;
804 
805   // Execute the action to actually build the module in-place. Use a separate
806   // thread so that we get a stack large enough.
807   const unsigned ThreadStackSize = 8 << 20;
808   llvm::CrashRecoveryContext CRC;
809   CompileModuleMapData Data = { Instance, CreateModuleAction };
810   CRC.RunSafelyOnThread(&doCompileMapModule, &Data, ThreadStackSize);
811 
812   // Delete the temporary module map file.
813   // FIXME: Even though we're executing under crash protection, it would still
814   // be nice to do this with RemoveFileOnSignal when we can. However, that
815   // doesn't make sense for all clients, so clean this up manually.
816   if (!TempModuleMapFileName.empty())
817     llvm::sys::Path(TempModuleMapFileName).eraseFromDisk();
818 }
819 
820 Module *CompilerInstance::loadModule(SourceLocation ImportLoc,
821                                      ModuleIdPath Path,
822                                      Module::NameVisibilityKind Visibility,
823                                      bool IsInclusionDirective) {
824   // If we've already handled this import, just return the cached result.
825   // This one-element cache is important to eliminate redundant diagnostics
826   // when both the preprocessor and parser see the same import declaration.
827   if (!ImportLoc.isInvalid() && LastModuleImportLoc == ImportLoc) {
828     // Make the named module visible.
829     if (LastModuleImportResult)
830       ModuleManager->makeModuleVisible(LastModuleImportResult, Visibility);
831     return LastModuleImportResult;
832   }
833 
834   // Determine what file we're searching from.
835   SourceManager &SourceMgr = getSourceManager();
836   SourceLocation ExpandedImportLoc = SourceMgr.getExpansionLoc(ImportLoc);
837   const FileEntry *CurFile
838     = SourceMgr.getFileEntryForID(SourceMgr.getFileID(ExpandedImportLoc));
839   if (!CurFile)
840     CurFile = SourceMgr.getFileEntryForID(SourceMgr.getMainFileID());
841 
842   StringRef ModuleName = Path[0].first->getName();
843   SourceLocation ModuleNameLoc = Path[0].second;
844 
845   clang::Module *Module = 0;
846 
847   // If we don't already have information on this module, load the module now.
848   llvm::DenseMap<const IdentifierInfo *, clang::Module *>::iterator Known
849     = KnownModules.find(Path[0].first);
850   if (Known != KnownModules.end()) {
851     // Retrieve the cached top-level module.
852     Module = Known->second;
853   } else if (ModuleName == getLangOpts().CurrentModule) {
854     // This is the module we're building.
855     Module = PP->getHeaderSearchInfo().getModuleMap().findModule(ModuleName);
856     Known = KnownModules.insert(std::make_pair(Path[0].first, Module)).first;
857   } else {
858     // Search for a module with the given name.
859     Module = PP->getHeaderSearchInfo().lookupModule(ModuleName);
860     std::string ModuleFileName;
861     if (Module)
862       ModuleFileName = PP->getHeaderSearchInfo().getModuleFileName(Module);
863     else
864       ModuleFileName = PP->getHeaderSearchInfo().getModuleFileName(ModuleName);
865 
866     if (ModuleFileName.empty()) {
867       getDiagnostics().Report(ModuleNameLoc, diag::err_module_not_found)
868         << ModuleName
869         << SourceRange(ImportLoc, ModuleNameLoc);
870       LastModuleImportLoc = ImportLoc;
871       LastModuleImportResult = 0;
872       return 0;
873     }
874 
875     const FileEntry *ModuleFile
876       = getFileManager().getFile(ModuleFileName, /*OpenFile=*/false,
877                                  /*CacheFailure=*/false);
878     bool BuildingModule = false;
879     if (!ModuleFile && Module) {
880       // The module is not cached, but we have a module map from which we can
881       // build the module.
882 
883       // Check whether there is a cycle in the module graph.
884       SmallVectorImpl<std::string> &ModuleBuildPath
885         = getPreprocessorOpts().ModuleBuildPath;
886       SmallVectorImpl<std::string>::iterator Pos
887         = std::find(ModuleBuildPath.begin(), ModuleBuildPath.end(), ModuleName);
888       if (Pos != ModuleBuildPath.end()) {
889         llvm::SmallString<256> CyclePath;
890         for (; Pos != ModuleBuildPath.end(); ++Pos) {
891           CyclePath += *Pos;
892           CyclePath += " -> ";
893         }
894         CyclePath += ModuleName;
895 
896         getDiagnostics().Report(ModuleNameLoc, diag::err_module_cycle)
897           << ModuleName << CyclePath;
898         return 0;
899       }
900 
901       getDiagnostics().Report(ModuleNameLoc, diag::warn_module_build)
902         << ModuleName;
903       BuildingModule = true;
904       compileModule(*this, Module, ModuleFileName);
905       ModuleFile = FileMgr->getFile(ModuleFileName);
906     }
907 
908     if (!ModuleFile) {
909       getDiagnostics().Report(ModuleNameLoc,
910                               BuildingModule? diag::err_module_not_built
911                                             : diag::err_module_not_found)
912         << ModuleName
913         << SourceRange(ImportLoc, ModuleNameLoc);
914       return 0;
915     }
916 
917     // If we don't already have an ASTReader, create one now.
918     if (!ModuleManager) {
919       if (!hasASTContext())
920         createASTContext();
921 
922       std::string Sysroot = getHeaderSearchOpts().Sysroot;
923       const PreprocessorOptions &PPOpts = getPreprocessorOpts();
924       ModuleManager = new ASTReader(getPreprocessor(), *Context,
925                                     Sysroot.empty() ? "" : Sysroot.c_str(),
926                                     PPOpts.DisablePCHValidation,
927                                     PPOpts.DisableStatCache);
928       if (hasASTConsumer()) {
929         ModuleManager->setDeserializationListener(
930           getASTConsumer().GetASTDeserializationListener());
931         getASTContext().setASTMutationListener(
932           getASTConsumer().GetASTMutationListener());
933       }
934       llvm::OwningPtr<ExternalASTSource> Source;
935       Source.reset(ModuleManager);
936       getASTContext().setExternalSource(Source);
937       if (hasSema())
938         ModuleManager->InitializeSema(getSema());
939       if (hasASTConsumer())
940         ModuleManager->StartTranslationUnit(&getASTConsumer());
941     }
942 
943     // Try to load the module we found.
944     switch (ModuleManager->ReadAST(ModuleFile->getName(),
945                                    serialization::MK_Module)) {
946     case ASTReader::Success:
947       break;
948 
949     case ASTReader::IgnorePCH:
950       // FIXME: The ASTReader will already have complained, but can we showhorn
951       // that diagnostic information into a more useful form?
952       KnownModules[Path[0].first] = 0;
953       return 0;
954 
955     case ASTReader::Failure:
956       // Already complained, but note now that we failed.
957       KnownModules[Path[0].first] = 0;
958       return 0;
959     }
960 
961     if (!Module) {
962       // If we loaded the module directly, without finding a module map first,
963       // we'll have loaded the module's information from the module itself.
964       Module = PP->getHeaderSearchInfo().getModuleMap()
965                  .findModule((Path[0].first->getName()));
966     }
967 
968     // Cache the result of this top-level module lookup for later.
969     Known = KnownModules.insert(std::make_pair(Path[0].first, Module)).first;
970   }
971 
972   // If we never found the module, fail.
973   if (!Module)
974     return 0;
975 
976   // Verify that the rest of the module path actually corresponds to
977   // a submodule.
978   if (Path.size() > 1) {
979     for (unsigned I = 1, N = Path.size(); I != N; ++I) {
980       StringRef Name = Path[I].first->getName();
981       clang::Module *Sub = Module->findSubmodule(Name);
982 
983       if (!Sub) {
984         // Attempt to perform typo correction to find a module name that works.
985         llvm::SmallVector<StringRef, 2> Best;
986         unsigned BestEditDistance = (std::numeric_limits<unsigned>::max)();
987 
988         for (clang::Module::submodule_iterator J = Module->submodule_begin(),
989                                             JEnd = Module->submodule_end();
990              J != JEnd; ++J) {
991           unsigned ED = Name.edit_distance((*J)->Name,
992                                            /*AllowReplacements=*/true,
993                                            BestEditDistance);
994           if (ED <= BestEditDistance) {
995             if (ED < BestEditDistance) {
996               Best.clear();
997               BestEditDistance = ED;
998             }
999 
1000             Best.push_back((*J)->Name);
1001           }
1002         }
1003 
1004         // If there was a clear winner, user it.
1005         if (Best.size() == 1) {
1006           getDiagnostics().Report(Path[I].second,
1007                                   diag::err_no_submodule_suggest)
1008             << Path[I].first << Module->getFullModuleName() << Best[0]
1009             << SourceRange(Path[0].second, Path[I-1].second)
1010             << FixItHint::CreateReplacement(SourceRange(Path[I].second),
1011                                             Best[0]);
1012 
1013           Sub = Module->findSubmodule(Best[0]);
1014         }
1015       }
1016 
1017       if (!Sub) {
1018         // No submodule by this name. Complain, and don't look for further
1019         // submodules.
1020         getDiagnostics().Report(Path[I].second, diag::err_no_submodule)
1021           << Path[I].first << Module->getFullModuleName()
1022           << SourceRange(Path[0].second, Path[I-1].second);
1023         break;
1024       }
1025 
1026       Module = Sub;
1027     }
1028   }
1029 
1030   // Make the named module visible, if it's not already part of the module
1031   // we are parsing.
1032   if (ModuleName != getLangOpts().CurrentModule) {
1033     if (!Module->IsFromModuleFile) {
1034       // We have an umbrella header or directory that doesn't actually include
1035       // all of the headers within the directory it covers. Complain about
1036       // this missing submodule and recover by forgetting that we ever saw
1037       // this submodule.
1038       // FIXME: Should we detect this at module load time? It seems fairly
1039       // expensive (and rare).
1040       getDiagnostics().Report(ImportLoc, diag::warn_missing_submodule)
1041         << Module->getFullModuleName()
1042         << SourceRange(Path.front().second, Path.back().second);
1043 
1044       return 0;
1045     }
1046 
1047     // Check whether this module is available.
1048     StringRef Feature;
1049     if (!Module->isAvailable(getLangOpts(), getTarget(), Feature)) {
1050       getDiagnostics().Report(ImportLoc, diag::err_module_unavailable)
1051         << Module->getFullModuleName()
1052         << Feature
1053         << SourceRange(Path.front().second, Path.back().second);
1054       LastModuleImportLoc = ImportLoc;
1055       LastModuleImportResult = 0;
1056       return 0;
1057     }
1058 
1059     ModuleManager->makeModuleVisible(Module, Visibility);
1060   }
1061 
1062   // If this module import was due to an inclusion directive, create an
1063   // implicit import declaration to capture it in the AST.
1064   if (IsInclusionDirective && hasASTContext()) {
1065     TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
1066     TU->addDecl(ImportDecl::CreateImplicit(getASTContext(), TU,
1067                                            ImportLoc, Module,
1068                                            Path.back().second));
1069   }
1070 
1071   LastModuleImportLoc = ImportLoc;
1072   LastModuleImportResult = Module;
1073   return Module;
1074 }
1075