xref: /llvm-project/clang/lib/Frontend/CompilerInstance.cpp (revision 335c5a42e9cfa70436bce30a6867cb722cac339c)
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   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   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 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   IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
186   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 
262   InitializePreprocessor(*PP, PPOpts, getHeaderSearchOpts(), getFrontendOpts());
263 
264   // Set up the module path, including the hash for the
265   // module-creation options.
266   SmallString<256> SpecificModuleCache(
267                            getHeaderSearchOpts().ModuleCachePath);
268   if (!getHeaderSearchOpts().DisableModuleHash)
269     llvm::sys::path::append(SpecificModuleCache,
270                             getInvocation().getModuleHash());
271   PP->getHeaderSearchInfo().setModuleCachePath(SpecificModuleCache);
272 
273   // Handle generating dependencies, if requested.
274   const DependencyOutputOptions &DepOpts = getDependencyOutputOpts();
275   if (!DepOpts.OutputFile.empty())
276     AttachDependencyFileGen(*PP, DepOpts);
277   if (!DepOpts.DOTOutputFile.empty())
278     AttachDependencyGraphGen(*PP, DepOpts.DOTOutputFile,
279                              getHeaderSearchOpts().Sysroot);
280 
281 
282   // Handle generating header include information, if requested.
283   if (DepOpts.ShowHeaderIncludes)
284     AttachHeaderIncludeGen(*PP);
285   if (!DepOpts.HeaderIncludeOutputFile.empty()) {
286     StringRef OutputPath = DepOpts.HeaderIncludeOutputFile;
287     if (OutputPath == "-")
288       OutputPath = "";
289     AttachHeaderIncludeGen(*PP, /*ShowAllHeaders=*/true, OutputPath,
290                            /*ShowDepth=*/false);
291   }
292 }
293 
294 // ASTContext
295 
296 void CompilerInstance::createASTContext() {
297   Preprocessor &PP = getPreprocessor();
298   Context = new ASTContext(getLangOpts(), PP.getSourceManager(),
299                            &getTarget(), PP.getIdentifierTable(),
300                            PP.getSelectorTable(), PP.getBuiltinInfo(),
301                            /*size_reserve=*/ 0);
302 }
303 
304 // ExternalASTSource
305 
306 void CompilerInstance::createPCHExternalASTSource(StringRef Path,
307                                                   bool DisablePCHValidation,
308                                                   bool DisableStatCache,
309                                                  void *DeserializationListener){
310   OwningPtr<ExternalASTSource> Source;
311   bool Preamble = getPreprocessorOpts().PrecompiledPreambleBytes.first != 0;
312   Source.reset(createPCHExternalASTSource(Path, getHeaderSearchOpts().Sysroot,
313                                           DisablePCHValidation,
314                                           DisableStatCache,
315                                           getPreprocessor(), getASTContext(),
316                                           DeserializationListener,
317                                           Preamble));
318   ModuleManager = static_cast<ASTReader*>(Source.get());
319   getASTContext().setExternalSource(Source);
320 }
321 
322 ExternalASTSource *
323 CompilerInstance::createPCHExternalASTSource(StringRef Path,
324                                              const std::string &Sysroot,
325                                              bool DisablePCHValidation,
326                                              bool DisableStatCache,
327                                              Preprocessor &PP,
328                                              ASTContext &Context,
329                                              void *DeserializationListener,
330                                              bool Preamble) {
331   OwningPtr<ASTReader> Reader;
332   Reader.reset(new ASTReader(PP, Context,
333                              Sysroot.empty() ? "" : Sysroot.c_str(),
334                              DisablePCHValidation, DisableStatCache));
335 
336   Reader->setDeserializationListener(
337             static_cast<ASTDeserializationListener *>(DeserializationListener));
338   switch (Reader->ReadAST(Path,
339                           Preamble ? serialization::MK_Preamble
340                                    : serialization::MK_PCH)) {
341   case ASTReader::Success:
342     // Set the predefines buffer as suggested by the PCH reader. Typically, the
343     // predefines buffer will be empty.
344     PP.setPredefines(Reader->getSuggestedPredefines());
345     return Reader.take();
346 
347   case ASTReader::Failure:
348     // Unrecoverable failure: don't even try to process the input file.
349     break;
350 
351   case ASTReader::IgnorePCH:
352     // No suitable PCH file could be found. Return an error.
353     break;
354   }
355 
356   return 0;
357 }
358 
359 // Code Completion
360 
361 static bool EnableCodeCompletion(Preprocessor &PP,
362                                  const std::string &Filename,
363                                  unsigned Line,
364                                  unsigned Column) {
365   // Tell the source manager to chop off the given file at a specific
366   // line and column.
367   const FileEntry *Entry = PP.getFileManager().getFile(Filename);
368   if (!Entry) {
369     PP.getDiagnostics().Report(diag::err_fe_invalid_code_complete_file)
370       << Filename;
371     return true;
372   }
373 
374   // Truncate the named file at the given line/column.
375   PP.SetCodeCompletionPoint(Entry, Line, Column);
376   return false;
377 }
378 
379 void CompilerInstance::createCodeCompletionConsumer() {
380   const ParsedSourceLocation &Loc = getFrontendOpts().CodeCompletionAt;
381   if (!CompletionConsumer) {
382     CompletionConsumer.reset(
383       createCodeCompletionConsumer(getPreprocessor(),
384                                    Loc.FileName, Loc.Line, Loc.Column,
385                                    getFrontendOpts().ShowMacrosInCodeCompletion,
386                              getFrontendOpts().ShowCodePatternsInCodeCompletion,
387                            getFrontendOpts().ShowGlobalSymbolsInCodeCompletion,
388                                    llvm::outs()));
389     if (!CompletionConsumer)
390       return;
391   } else if (EnableCodeCompletion(getPreprocessor(), Loc.FileName,
392                                   Loc.Line, Loc.Column)) {
393     CompletionConsumer.reset();
394     return;
395   }
396 
397   if (CompletionConsumer->isOutputBinary() &&
398       llvm::sys::Program::ChangeStdoutToBinary()) {
399     getPreprocessor().getDiagnostics().Report(diag::err_fe_stdout_binary);
400     CompletionConsumer.reset();
401   }
402 }
403 
404 void CompilerInstance::createFrontendTimer() {
405   FrontendTimer.reset(new llvm::Timer("Clang front-end timer"));
406 }
407 
408 CodeCompleteConsumer *
409 CompilerInstance::createCodeCompletionConsumer(Preprocessor &PP,
410                                                const std::string &Filename,
411                                                unsigned Line,
412                                                unsigned Column,
413                                                bool ShowMacros,
414                                                bool ShowCodePatterns,
415                                                bool ShowGlobals,
416                                                raw_ostream &OS) {
417   if (EnableCodeCompletion(PP, Filename, Line, Column))
418     return 0;
419 
420   // Set up the creation routine for code-completion.
421   return new PrintingCodeCompleteConsumer(ShowMacros, ShowCodePatterns,
422                                           ShowGlobals, OS);
423 }
424 
425 void CompilerInstance::createSema(TranslationUnitKind TUKind,
426                                   CodeCompleteConsumer *CompletionConsumer) {
427   TheSema.reset(new Sema(getPreprocessor(), getASTContext(), getASTConsumer(),
428                          TUKind, CompletionConsumer));
429 }
430 
431 // Output Files
432 
433 void CompilerInstance::addOutputFile(const OutputFile &OutFile) {
434   assert(OutFile.OS && "Attempt to add empty stream to output list!");
435   OutputFiles.push_back(OutFile);
436 }
437 
438 void CompilerInstance::clearOutputFiles(bool EraseFiles) {
439   for (std::list<OutputFile>::iterator
440          it = OutputFiles.begin(), ie = OutputFiles.end(); it != ie; ++it) {
441     delete it->OS;
442     if (!it->TempFilename.empty()) {
443       if (EraseFiles) {
444         bool existed;
445         llvm::sys::fs::remove(it->TempFilename, existed);
446       } else {
447         SmallString<128> NewOutFile(it->Filename);
448 
449         // If '-working-directory' was passed, the output filename should be
450         // relative to that.
451         FileMgr->FixupRelativePath(NewOutFile);
452         if (llvm::error_code ec = llvm::sys::fs::rename(it->TempFilename,
453                                                         NewOutFile.str())) {
454           getDiagnostics().Report(diag::err_fe_unable_to_rename_temp)
455             << it->TempFilename << it->Filename << ec.message();
456 
457           bool existed;
458           llvm::sys::fs::remove(it->TempFilename, existed);
459         }
460       }
461     } else if (!it->Filename.empty() && EraseFiles)
462       llvm::sys::Path(it->Filename).eraseFromDisk();
463 
464   }
465   OutputFiles.clear();
466 }
467 
468 llvm::raw_fd_ostream *
469 CompilerInstance::createDefaultOutputFile(bool Binary,
470                                           StringRef InFile,
471                                           StringRef Extension) {
472   return createOutputFile(getFrontendOpts().OutputFile, Binary,
473                           /*RemoveFileOnSignal=*/true, InFile, Extension);
474 }
475 
476 llvm::raw_fd_ostream *
477 CompilerInstance::createOutputFile(StringRef OutputPath,
478                                    bool Binary, bool RemoveFileOnSignal,
479                                    StringRef InFile,
480                                    StringRef Extension,
481                                    bool UseTemporary) {
482   std::string Error, OutputPathName, TempPathName;
483   llvm::raw_fd_ostream *OS = createOutputFile(OutputPath, Error, Binary,
484                                               RemoveFileOnSignal,
485                                               InFile, Extension,
486                                               UseTemporary,
487                                               &OutputPathName,
488                                               &TempPathName);
489   if (!OS) {
490     getDiagnostics().Report(diag::err_fe_unable_to_open_output)
491       << OutputPath << Error;
492     return 0;
493   }
494 
495   // Add the output file -- but don't try to remove "-", since this means we are
496   // using stdin.
497   addOutputFile(OutputFile((OutputPathName != "-") ? OutputPathName : "",
498                 TempPathName, OS));
499 
500   return OS;
501 }
502 
503 llvm::raw_fd_ostream *
504 CompilerInstance::createOutputFile(StringRef OutputPath,
505                                    std::string &Error,
506                                    bool Binary,
507                                    bool RemoveFileOnSignal,
508                                    StringRef InFile,
509                                    StringRef Extension,
510                                    bool UseTemporary,
511                                    std::string *ResultPathName,
512                                    std::string *TempPathName) {
513   std::string OutFile, TempFile;
514   if (!OutputPath.empty()) {
515     OutFile = OutputPath;
516   } else if (InFile == "-") {
517     OutFile = "-";
518   } else if (!Extension.empty()) {
519     llvm::sys::Path Path(InFile);
520     Path.eraseSuffix();
521     Path.appendSuffix(Extension);
522     OutFile = Path.str();
523   } else {
524     OutFile = "-";
525   }
526 
527   OwningPtr<llvm::raw_fd_ostream> OS;
528   std::string OSFile;
529 
530   if (UseTemporary && OutFile != "-") {
531     llvm::sys::Path OutPath(OutFile);
532     // Only create the temporary if we can actually write to OutPath, otherwise
533     // we want to fail early.
534     bool Exists;
535     if ((llvm::sys::fs::exists(OutPath.str(), Exists) || !Exists) ||
536         (OutPath.isRegularFile() && OutPath.canWrite())) {
537       // Create a temporary file.
538       SmallString<128> TempPath;
539       TempPath = OutFile;
540       TempPath += "-%%%%%%%%";
541       int fd;
542       if (llvm::sys::fs::unique_file(TempPath.str(), fd, TempPath,
543                                /*makeAbsolute=*/false) == llvm::errc::success) {
544         OS.reset(new llvm::raw_fd_ostream(fd, /*shouldClose=*/true));
545         OSFile = TempFile = TempPath.str();
546       }
547     }
548   }
549 
550   if (!OS) {
551     OSFile = OutFile;
552     OS.reset(
553       new llvm::raw_fd_ostream(OSFile.c_str(), Error,
554                                (Binary ? llvm::raw_fd_ostream::F_Binary : 0)));
555     if (!Error.empty())
556       return 0;
557   }
558 
559   // Make sure the out stream file gets removed if we crash.
560   if (RemoveFileOnSignal)
561     llvm::sys::RemoveFileOnSignal(llvm::sys::Path(OSFile));
562 
563   if (ResultPathName)
564     *ResultPathName = OutFile;
565   if (TempPathName)
566     *TempPathName = TempFile;
567 
568   return OS.take();
569 }
570 
571 // Initialization Utilities
572 
573 bool CompilerInstance::InitializeSourceManager(StringRef InputFile,
574                                                SrcMgr::CharacteristicKind Kind){
575   return InitializeSourceManager(InputFile, Kind, getDiagnostics(),
576                                  getFileManager(), getSourceManager(),
577                                  getFrontendOpts());
578 }
579 
580 bool CompilerInstance::InitializeSourceManager(StringRef InputFile,
581                                                SrcMgr::CharacteristicKind Kind,
582                                                DiagnosticsEngine &Diags,
583                                                FileManager &FileMgr,
584                                                SourceManager &SourceMgr,
585                                                const FrontendOptions &Opts) {
586   // Figure out where to get and map in the main file.
587   if (InputFile != "-") {
588     const FileEntry *File = FileMgr.getFile(InputFile);
589     if (!File) {
590       Diags.Report(diag::err_fe_error_reading) << InputFile;
591       return false;
592     }
593     SourceMgr.createMainFileID(File, Kind);
594   } else {
595     OwningPtr<llvm::MemoryBuffer> SB;
596     if (llvm::MemoryBuffer::getSTDIN(SB)) {
597       // FIXME: Give ec.message() in this diag.
598       Diags.Report(diag::err_fe_error_reading_stdin);
599       return false;
600     }
601     const FileEntry *File = FileMgr.getVirtualFile(SB->getBufferIdentifier(),
602                                                    SB->getBufferSize(), 0);
603     SourceMgr.createMainFileID(File, Kind);
604     SourceMgr.overrideFileContents(File, SB.take());
605   }
606 
607   assert(!SourceMgr.getMainFileID().isInvalid() &&
608          "Couldn't establish MainFileID!");
609   return true;
610 }
611 
612 // High-Level Operations
613 
614 bool CompilerInstance::ExecuteAction(FrontendAction &Act) {
615   assert(hasDiagnostics() && "Diagnostics engine is not initialized!");
616   assert(!getFrontendOpts().ShowHelp && "Client must handle '-help'!");
617   assert(!getFrontendOpts().ShowVersion && "Client must handle '-version'!");
618 
619   // FIXME: Take this as an argument, once all the APIs we used have moved to
620   // taking it as an input instead of hard-coding llvm::errs.
621   raw_ostream &OS = llvm::errs();
622 
623   // Create the target instance.
624   setTarget(TargetInfo::CreateTargetInfo(getDiagnostics(), getTargetOpts()));
625   if (!hasTarget())
626     return false;
627 
628   // Inform the target of the language options.
629   //
630   // FIXME: We shouldn't need to do this, the target should be immutable once
631   // created. This complexity should be lifted elsewhere.
632   getTarget().setForcedLangOptions(getLangOpts());
633 
634   // Validate/process some options.
635   if (getHeaderSearchOpts().Verbose)
636     OS << "clang -cc1 version " CLANG_VERSION_STRING
637        << " based upon " << PACKAGE_STRING
638        << " default target " << llvm::sys::getDefaultTargetTriple() << "\n";
639 
640   if (getFrontendOpts().ShowTimers)
641     createFrontendTimer();
642 
643   if (getFrontendOpts().ShowStats)
644     llvm::EnableStatistics();
645 
646   for (unsigned i = 0, e = getFrontendOpts().Inputs.size(); i != e; ++i) {
647     // Reset the ID tables if we are reusing the SourceManager.
648     if (hasSourceManager())
649       getSourceManager().clearIDTables();
650 
651     if (Act.BeginSourceFile(*this, getFrontendOpts().Inputs[i])) {
652       Act.Execute();
653       Act.EndSourceFile();
654     }
655   }
656 
657   // Notify the diagnostic client that all files were processed.
658   getDiagnostics().getClient()->finish();
659 
660   if (getDiagnosticOpts().ShowCarets) {
661     // We can have multiple diagnostics sharing one diagnostic client.
662     // Get the total number of warnings/errors from the client.
663     unsigned NumWarnings = getDiagnostics().getClient()->getNumWarnings();
664     unsigned NumErrors = getDiagnostics().getClient()->getNumErrors();
665 
666     if (NumWarnings)
667       OS << NumWarnings << " warning" << (NumWarnings == 1 ? "" : "s");
668     if (NumWarnings && NumErrors)
669       OS << " and ";
670     if (NumErrors)
671       OS << NumErrors << " error" << (NumErrors == 1 ? "" : "s");
672     if (NumWarnings || NumErrors)
673       OS << " generated.\n";
674   }
675 
676   if (getFrontendOpts().ShowStats && hasFileManager()) {
677     getFileManager().PrintStats();
678     OS << "\n";
679   }
680 
681   return !getDiagnostics().getClient()->getNumErrors();
682 }
683 
684 /// \brief Determine the appropriate source input kind based on language
685 /// options.
686 static InputKind getSourceInputKindFromOptions(const LangOptions &LangOpts) {
687   if (LangOpts.OpenCL)
688     return IK_OpenCL;
689   if (LangOpts.CUDA)
690     return IK_CUDA;
691   if (LangOpts.ObjC1)
692     return LangOpts.CPlusPlus? IK_ObjCXX : IK_ObjC;
693   return LangOpts.CPlusPlus? IK_CXX : IK_C;
694 }
695 
696 namespace {
697   struct CompileModuleMapData {
698     CompilerInstance &Instance;
699     GenerateModuleAction &CreateModuleAction;
700   };
701 }
702 
703 /// \brief Helper function that executes the module-generating action under
704 /// a crash recovery context.
705 static void doCompileMapModule(void *UserData) {
706   CompileModuleMapData &Data
707     = *reinterpret_cast<CompileModuleMapData *>(UserData);
708   Data.Instance.ExecuteAction(Data.CreateModuleAction);
709 }
710 
711 /// \brief Compile a module file for the given module, using the options
712 /// provided by the importing compiler instance.
713 static void compileModule(CompilerInstance &ImportingInstance,
714                           Module *Module,
715                           StringRef ModuleFileName) {
716   llvm::LockFileManager Locked(ModuleFileName);
717   switch (Locked) {
718   case llvm::LockFileManager::LFS_Error:
719     return;
720 
721   case llvm::LockFileManager::LFS_Owned:
722     // We're responsible for building the module ourselves. Do so below.
723     break;
724 
725   case llvm::LockFileManager::LFS_Shared:
726     // Someone else is responsible for building the module. Wait for them to
727     // finish.
728     Locked.waitForUnlock();
729     break;
730   }
731 
732   ModuleMap &ModMap
733     = ImportingInstance.getPreprocessor().getHeaderSearchInfo().getModuleMap();
734 
735   // Construct a compiler invocation for creating this module.
736   IntrusiveRefCntPtr<CompilerInvocation> Invocation
737     (new CompilerInvocation(ImportingInstance.getInvocation()));
738 
739   PreprocessorOptions &PPOpts = Invocation->getPreprocessorOpts();
740 
741   // For any options that aren't intended to affect how a module is built,
742   // reset them to their default values.
743   Invocation->getLangOpts()->resetNonModularOptions();
744   PPOpts.resetNonModularOptions();
745 
746   // Note the name of the module we're building.
747   Invocation->getLangOpts()->CurrentModule = Module->getTopLevelModuleName();
748 
749   // Note that this module is part of the module build path, so that we
750   // can detect cycles in the module graph.
751   PPOpts.ModuleBuildPath.push_back(Module->getTopLevelModuleName());
752 
753   // If there is a module map file, build the module using the module map.
754   // Set up the inputs/outputs so that we build the module from its umbrella
755   // header.
756   FrontendOptions &FrontendOpts = Invocation->getFrontendOpts();
757   FrontendOpts.OutputFile = ModuleFileName.str();
758   FrontendOpts.DisableFree = false;
759   FrontendOpts.Inputs.clear();
760   InputKind IK = getSourceInputKindFromOptions(*Invocation->getLangOpts());
761 
762   // Get or create the module map that we'll use to build this module.
763   SmallString<128> TempModuleMapFileName;
764   if (const FileEntry *ModuleMapFile
765                                   = ModMap.getContainingModuleMapFile(Module)) {
766     // Use the module map where this module resides.
767     FrontendOpts.Inputs.push_back(FrontendInputFile(ModuleMapFile->getName(),
768                                                     IK));
769   } else {
770     // Create a temporary module map file.
771     TempModuleMapFileName = Module->Name;
772     TempModuleMapFileName += "-%%%%%%%%.map";
773     int FD;
774     if (llvm::sys::fs::unique_file(TempModuleMapFileName.str(), FD,
775                                    TempModuleMapFileName,
776                                    /*makeAbsolute=*/true)
777           != llvm::errc::success) {
778       ImportingInstance.getDiagnostics().Report(diag::err_module_map_temp_file)
779         << TempModuleMapFileName;
780       return;
781     }
782     // Print the module map to this file.
783     llvm::raw_fd_ostream OS(FD, /*shouldClose=*/true);
784     Module->print(OS);
785     FrontendOpts.Inputs.push_back(
786       FrontendInputFile(TempModuleMapFileName.str().str(), IK));
787   }
788 
789   // Don't free the remapped file buffers; they are owned by our caller.
790   PPOpts.RetainRemappedFileBuffers = true;
791 
792   Invocation->getDiagnosticOpts().VerifyDiagnostics = 0;
793   assert(ImportingInstance.getInvocation().getModuleHash() ==
794          Invocation->getModuleHash() && "Module hash mismatch!");
795 
796   // Construct a compiler instance that will be used to actually create the
797   // module.
798   CompilerInstance Instance;
799   Instance.setInvocation(&*Invocation);
800   Instance.createDiagnostics(/*argc=*/0, /*argv=*/0,
801                              &ImportingInstance.getDiagnosticClient(),
802                              /*ShouldOwnClient=*/true,
803                              /*ShouldCloneClient=*/true);
804 
805   // Construct a module-generating action.
806   GenerateModuleAction CreateModuleAction;
807 
808   // Execute the action to actually build the module in-place. Use a separate
809   // thread so that we get a stack large enough.
810   const unsigned ThreadStackSize = 8 << 20;
811   llvm::CrashRecoveryContext CRC;
812   CompileModuleMapData Data = { Instance, CreateModuleAction };
813   CRC.RunSafelyOnThread(&doCompileMapModule, &Data, ThreadStackSize);
814 
815   // Delete the temporary module map file.
816   // FIXME: Even though we're executing under crash protection, it would still
817   // be nice to do this with RemoveFileOnSignal when we can. However, that
818   // doesn't make sense for all clients, so clean this up manually.
819   if (!TempModuleMapFileName.empty())
820     llvm::sys::Path(TempModuleMapFileName).eraseFromDisk();
821 }
822 
823 Module *CompilerInstance::loadModule(SourceLocation ImportLoc,
824                                      ModuleIdPath Path,
825                                      Module::NameVisibilityKind Visibility,
826                                      bool IsInclusionDirective) {
827   // If we've already handled this import, just return the cached result.
828   // This one-element cache is important to eliminate redundant diagnostics
829   // when both the preprocessor and parser see the same import declaration.
830   if (!ImportLoc.isInvalid() && LastModuleImportLoc == ImportLoc) {
831     // Make the named module visible.
832     if (LastModuleImportResult)
833       ModuleManager->makeModuleVisible(LastModuleImportResult, Visibility);
834     return LastModuleImportResult;
835   }
836 
837   // Determine what file we're searching from.
838   SourceManager &SourceMgr = getSourceManager();
839   SourceLocation ExpandedImportLoc = SourceMgr.getExpansionLoc(ImportLoc);
840   const FileEntry *CurFile
841     = SourceMgr.getFileEntryForID(SourceMgr.getFileID(ExpandedImportLoc));
842   if (!CurFile)
843     CurFile = SourceMgr.getFileEntryForID(SourceMgr.getMainFileID());
844 
845   StringRef ModuleName = Path[0].first->getName();
846   SourceLocation ModuleNameLoc = Path[0].second;
847 
848   clang::Module *Module = 0;
849 
850   // If we don't already have information on this module, load the module now.
851   llvm::DenseMap<const IdentifierInfo *, clang::Module *>::iterator Known
852     = KnownModules.find(Path[0].first);
853   if (Known != KnownModules.end()) {
854     // Retrieve the cached top-level module.
855     Module = Known->second;
856   } else if (ModuleName == getLangOpts().CurrentModule) {
857     // This is the module we're building.
858     Module = PP->getHeaderSearchInfo().getModuleMap().findModule(ModuleName);
859     Known = KnownModules.insert(std::make_pair(Path[0].first, Module)).first;
860   } else {
861     // Search for a module with the given name.
862     Module = PP->getHeaderSearchInfo().lookupModule(ModuleName);
863     std::string ModuleFileName;
864     if (Module)
865       ModuleFileName = PP->getHeaderSearchInfo().getModuleFileName(Module);
866     else
867       ModuleFileName = PP->getHeaderSearchInfo().getModuleFileName(ModuleName);
868 
869     if (ModuleFileName.empty()) {
870       getDiagnostics().Report(ModuleNameLoc, diag::err_module_not_found)
871         << ModuleName
872         << SourceRange(ImportLoc, ModuleNameLoc);
873       LastModuleImportLoc = ImportLoc;
874       LastModuleImportResult = 0;
875       return 0;
876     }
877 
878     const FileEntry *ModuleFile
879       = getFileManager().getFile(ModuleFileName, /*OpenFile=*/false,
880                                  /*CacheFailure=*/false);
881     bool BuildingModule = false;
882     if (!ModuleFile && Module) {
883       // The module is not cached, but we have a module map from which we can
884       // build the module.
885 
886       // Check whether there is a cycle in the module graph.
887       SmallVectorImpl<std::string> &ModuleBuildPath
888         = getPreprocessorOpts().ModuleBuildPath;
889       SmallVectorImpl<std::string>::iterator Pos
890         = std::find(ModuleBuildPath.begin(), ModuleBuildPath.end(), ModuleName);
891       if (Pos != ModuleBuildPath.end()) {
892         SmallString<256> CyclePath;
893         for (; Pos != ModuleBuildPath.end(); ++Pos) {
894           CyclePath += *Pos;
895           CyclePath += " -> ";
896         }
897         CyclePath += ModuleName;
898 
899         getDiagnostics().Report(ModuleNameLoc, diag::err_module_cycle)
900           << ModuleName << CyclePath;
901         return 0;
902       }
903 
904       getDiagnostics().Report(ModuleNameLoc, diag::warn_module_build)
905         << ModuleName;
906       BuildingModule = true;
907       compileModule(*this, Module, ModuleFileName);
908       ModuleFile = FileMgr->getFile(ModuleFileName);
909     }
910 
911     if (!ModuleFile) {
912       getDiagnostics().Report(ModuleNameLoc,
913                               BuildingModule? diag::err_module_not_built
914                                             : diag::err_module_not_found)
915         << ModuleName
916         << SourceRange(ImportLoc, ModuleNameLoc);
917       return 0;
918     }
919 
920     // If we don't already have an ASTReader, create one now.
921     if (!ModuleManager) {
922       if (!hasASTContext())
923         createASTContext();
924 
925       std::string Sysroot = getHeaderSearchOpts().Sysroot;
926       const PreprocessorOptions &PPOpts = getPreprocessorOpts();
927       ModuleManager = new ASTReader(getPreprocessor(), *Context,
928                                     Sysroot.empty() ? "" : Sysroot.c_str(),
929                                     PPOpts.DisablePCHValidation,
930                                     PPOpts.DisableStatCache);
931       if (hasASTConsumer()) {
932         ModuleManager->setDeserializationListener(
933           getASTConsumer().GetASTDeserializationListener());
934         getASTContext().setASTMutationListener(
935           getASTConsumer().GetASTMutationListener());
936       }
937       OwningPtr<ExternalASTSource> Source;
938       Source.reset(ModuleManager);
939       getASTContext().setExternalSource(Source);
940       if (hasSema())
941         ModuleManager->InitializeSema(getSema());
942       if (hasASTConsumer())
943         ModuleManager->StartTranslationUnit(&getASTConsumer());
944     }
945 
946     // Try to load the module we found.
947     switch (ModuleManager->ReadAST(ModuleFile->getName(),
948                                    serialization::MK_Module)) {
949     case ASTReader::Success:
950       break;
951 
952     case ASTReader::IgnorePCH:
953       // FIXME: The ASTReader will already have complained, but can we showhorn
954       // that diagnostic information into a more useful form?
955       KnownModules[Path[0].first] = 0;
956       return 0;
957 
958     case ASTReader::Failure:
959       // Already complained, but note now that we failed.
960       KnownModules[Path[0].first] = 0;
961       return 0;
962     }
963 
964     if (!Module) {
965       // If we loaded the module directly, without finding a module map first,
966       // we'll have loaded the module's information from the module itself.
967       Module = PP->getHeaderSearchInfo().getModuleMap()
968                  .findModule((Path[0].first->getName()));
969     }
970 
971     // Cache the result of this top-level module lookup for later.
972     Known = KnownModules.insert(std::make_pair(Path[0].first, Module)).first;
973   }
974 
975   // If we never found the module, fail.
976   if (!Module)
977     return 0;
978 
979   // Verify that the rest of the module path actually corresponds to
980   // a submodule.
981   if (Path.size() > 1) {
982     for (unsigned I = 1, N = Path.size(); I != N; ++I) {
983       StringRef Name = Path[I].first->getName();
984       clang::Module *Sub = Module->findSubmodule(Name);
985 
986       if (!Sub) {
987         // Attempt to perform typo correction to find a module name that works.
988         llvm::SmallVector<StringRef, 2> Best;
989         unsigned BestEditDistance = (std::numeric_limits<unsigned>::max)();
990 
991         for (clang::Module::submodule_iterator J = Module->submodule_begin(),
992                                             JEnd = Module->submodule_end();
993              J != JEnd; ++J) {
994           unsigned ED = Name.edit_distance((*J)->Name,
995                                            /*AllowReplacements=*/true,
996                                            BestEditDistance);
997           if (ED <= BestEditDistance) {
998             if (ED < BestEditDistance) {
999               Best.clear();
1000               BestEditDistance = ED;
1001             }
1002 
1003             Best.push_back((*J)->Name);
1004           }
1005         }
1006 
1007         // If there was a clear winner, user it.
1008         if (Best.size() == 1) {
1009           getDiagnostics().Report(Path[I].second,
1010                                   diag::err_no_submodule_suggest)
1011             << Path[I].first << Module->getFullModuleName() << Best[0]
1012             << SourceRange(Path[0].second, Path[I-1].second)
1013             << FixItHint::CreateReplacement(SourceRange(Path[I].second),
1014                                             Best[0]);
1015 
1016           Sub = Module->findSubmodule(Best[0]);
1017         }
1018       }
1019 
1020       if (!Sub) {
1021         // No submodule by this name. Complain, and don't look for further
1022         // submodules.
1023         getDiagnostics().Report(Path[I].second, diag::err_no_submodule)
1024           << Path[I].first << Module->getFullModuleName()
1025           << SourceRange(Path[0].second, Path[I-1].second);
1026         break;
1027       }
1028 
1029       Module = Sub;
1030     }
1031   }
1032 
1033   // Make the named module visible, if it's not already part of the module
1034   // we are parsing.
1035   if (ModuleName != getLangOpts().CurrentModule) {
1036     if (!Module->IsFromModuleFile) {
1037       // We have an umbrella header or directory that doesn't actually include
1038       // all of the headers within the directory it covers. Complain about
1039       // this missing submodule and recover by forgetting that we ever saw
1040       // this submodule.
1041       // FIXME: Should we detect this at module load time? It seems fairly
1042       // expensive (and rare).
1043       getDiagnostics().Report(ImportLoc, diag::warn_missing_submodule)
1044         << Module->getFullModuleName()
1045         << SourceRange(Path.front().second, Path.back().second);
1046 
1047       return 0;
1048     }
1049 
1050     // Check whether this module is available.
1051     StringRef Feature;
1052     if (!Module->isAvailable(getLangOpts(), getTarget(), Feature)) {
1053       getDiagnostics().Report(ImportLoc, diag::err_module_unavailable)
1054         << Module->getFullModuleName()
1055         << Feature
1056         << SourceRange(Path.front().second, Path.back().second);
1057       LastModuleImportLoc = ImportLoc;
1058       LastModuleImportResult = 0;
1059       return 0;
1060     }
1061 
1062     ModuleManager->makeModuleVisible(Module, Visibility);
1063   }
1064 
1065   // If this module import was due to an inclusion directive, create an
1066   // implicit import declaration to capture it in the AST.
1067   if (IsInclusionDirective && hasASTContext()) {
1068     TranslationUnitDecl *TU = getASTContext().getTranslationUnitDecl();
1069     TU->addDecl(ImportDecl::CreateImplicit(getASTContext(), TU,
1070                                            ImportLoc, Module,
1071                                            Path.back().second));
1072   }
1073 
1074   LastModuleImportLoc = ImportLoc;
1075   LastModuleImportResult = Module;
1076   return Module;
1077 }
1078