ASTUnit.cpp revision 03201fbbdeb3eb7f465610b09c281ee6aa84e3ca 
1//===--- ASTUnit.cpp - ASTUnit utility ------------------------------------===//
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// ASTUnit Implementation.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Frontend/ASTUnit.h"
15#include "clang/AST/ASTContext.h"
16#include "clang/AST/ASTConsumer.h"
17#include "clang/AST/DeclVisitor.h"
18#include "clang/AST/TypeOrdering.h"
19#include "clang/AST/StmtVisitor.h"
20#include "clang/Driver/Compilation.h"
21#include "clang/Driver/Driver.h"
22#include "clang/Driver/Job.h"
23#include "clang/Driver/ArgList.h"
24#include "clang/Driver/Options.h"
25#include "clang/Driver/Tool.h"
26#include "clang/Frontend/CompilerInstance.h"
27#include "clang/Frontend/FrontendActions.h"
28#include "clang/Frontend/FrontendDiagnostic.h"
29#include "clang/Frontend/FrontendOptions.h"
30#include "clang/Frontend/Utils.h"
31#include "clang/Serialization/ASTReader.h"
32#include "clang/Serialization/ASTSerializationListener.h"
33#include "clang/Serialization/ASTWriter.h"
34#include "clang/Lex/HeaderSearch.h"
35#include "clang/Lex/Preprocessor.h"
36#include "clang/Basic/TargetOptions.h"
37#include "clang/Basic/TargetInfo.h"
38#include "clang/Basic/Diagnostic.h"
39#include "llvm/ADT/StringExtras.h"
40#include "llvm/ADT/StringSet.h"
41#include "llvm/Support/Atomic.h"
42#include "llvm/Support/MemoryBuffer.h"
43#include "llvm/Support/Host.h"
44#include "llvm/Support/Path.h"
45#include "llvm/Support/raw_ostream.h"
46#include "llvm/Support/Timer.h"
47#include "llvm/Support/CrashRecoveryContext.h"
48#include <cstdlib>
49#include <cstdio>
50#include <sys/stat.h>
51using namespace clang;
52
53using llvm::TimeRecord;
54
55namespace {
56  class SimpleTimer {
57    bool WantTiming;
58    TimeRecord Start;
59    std::string Output;
60
61  public:
62    explicit SimpleTimer(bool WantTiming) : WantTiming(WantTiming) {
63      if (WantTiming)
64        Start = TimeRecord::getCurrentTime();
65    }
66
67    void setOutput(const llvm::Twine &Output) {
68      if (WantTiming)
69        this->Output = Output.str();
70    }
71
72    ~SimpleTimer() {
73      if (WantTiming) {
74        TimeRecord Elapsed = TimeRecord::getCurrentTime();
75        Elapsed -= Start;
76        llvm::errs() << Output << ':';
77        Elapsed.print(Elapsed, llvm::errs());
78        llvm::errs() << '\n';
79      }
80    }
81  };
82}
83
84/// \brief After failing to build a precompiled preamble (due to
85/// errors in the source that occurs in the preamble), the number of
86/// reparses during which we'll skip even trying to precompile the
87/// preamble.
88const unsigned DefaultPreambleRebuildInterval = 5;
89
90/// \brief Tracks the number of ASTUnit objects that are currently active.
91///
92/// Used for debugging purposes only.
93static llvm::sys::cas_flag ActiveASTUnitObjects;
94
95ASTUnit::ASTUnit(bool _MainFileIsAST)
96  : OnlyLocalDecls(false), CaptureDiagnostics(false),
97    MainFileIsAST(_MainFileIsAST),
98    CompleteTranslationUnit(true), WantTiming(getenv("LIBCLANG_TIMING")),
99    OwnsRemappedFileBuffers(true),
100    NumStoredDiagnosticsFromDriver(0),
101    ConcurrencyCheckValue(CheckUnlocked),
102    PreambleRebuildCounter(0), SavedMainFileBuffer(0), PreambleBuffer(0),
103    ShouldCacheCodeCompletionResults(false),
104    CompletionCacheTopLevelHashValue(0),
105    PreambleTopLevelHashValue(0),
106    CurrentTopLevelHashValue(0),
107    UnsafeToFree(false) {
108  if (getenv("LIBCLANG_OBJTRACKING")) {
109    llvm::sys::AtomicIncrement(&ActiveASTUnitObjects);
110    fprintf(stderr, "+++ %d translation units\n", ActiveASTUnitObjects);
111  }
112}
113
114ASTUnit::~ASTUnit() {
115  ConcurrencyCheckValue = CheckLocked;
116  CleanTemporaryFiles();
117  if (!PreambleFile.empty())
118    llvm::sys::Path(PreambleFile).eraseFromDisk();
119
120  // Free the buffers associated with remapped files. We are required to
121  // perform this operation here because we explicitly request that the
122  // compiler instance *not* free these buffers for each invocation of the
123  // parser.
124  if (Invocation.get() && OwnsRemappedFileBuffers) {
125    PreprocessorOptions &PPOpts = Invocation->getPreprocessorOpts();
126    for (PreprocessorOptions::remapped_file_buffer_iterator
127           FB = PPOpts.remapped_file_buffer_begin(),
128           FBEnd = PPOpts.remapped_file_buffer_end();
129         FB != FBEnd;
130         ++FB)
131      delete FB->second;
132  }
133
134  delete SavedMainFileBuffer;
135  delete PreambleBuffer;
136
137  ClearCachedCompletionResults();
138
139  if (getenv("LIBCLANG_OBJTRACKING")) {
140    llvm::sys::AtomicDecrement(&ActiveASTUnitObjects);
141    fprintf(stderr, "--- %d translation units\n", ActiveASTUnitObjects);
142  }
143}
144
145void ASTUnit::CleanTemporaryFiles() {
146  for (unsigned I = 0, N = TemporaryFiles.size(); I != N; ++I)
147    TemporaryFiles[I].eraseFromDisk();
148  TemporaryFiles.clear();
149}
150
151/// \brief Determine the set of code-completion contexts in which this
152/// declaration should be shown.
153static unsigned getDeclShowContexts(NamedDecl *ND,
154                                    const LangOptions &LangOpts,
155                                    bool &IsNestedNameSpecifier) {
156  IsNestedNameSpecifier = false;
157
158  if (isa<UsingShadowDecl>(ND))
159    ND = dyn_cast<NamedDecl>(ND->getUnderlyingDecl());
160  if (!ND)
161    return 0;
162
163  unsigned Contexts = 0;
164  if (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND) ||
165      isa<ClassTemplateDecl>(ND) || isa<TemplateTemplateParmDecl>(ND)) {
166    // Types can appear in these contexts.
167    if (LangOpts.CPlusPlus || !isa<TagDecl>(ND))
168      Contexts |= (1 << (CodeCompletionContext::CCC_TopLevel - 1))
169                | (1 << (CodeCompletionContext::CCC_ObjCIvarList - 1))
170                | (1 << (CodeCompletionContext::CCC_ClassStructUnion - 1))
171                | (1 << (CodeCompletionContext::CCC_Statement - 1))
172                | (1 << (CodeCompletionContext::CCC_Type - 1))
173              | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1));
174
175    // In C++, types can appear in expressions contexts (for functional casts).
176    if (LangOpts.CPlusPlus)
177      Contexts |= (1 << (CodeCompletionContext::CCC_Expression - 1));
178
179    // In Objective-C, message sends can send interfaces. In Objective-C++,
180    // all types are available due to functional casts.
181    if (LangOpts.CPlusPlus || isa<ObjCInterfaceDecl>(ND))
182      Contexts |= (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1));
183
184    // Deal with tag names.
185    if (isa<EnumDecl>(ND)) {
186      Contexts |= (1 << (CodeCompletionContext::CCC_EnumTag - 1));
187
188      // Part of the nested-name-specifier in C++0x.
189      if (LangOpts.CPlusPlus0x)
190        IsNestedNameSpecifier = true;
191    } else if (RecordDecl *Record = dyn_cast<RecordDecl>(ND)) {
192      if (Record->isUnion())
193        Contexts |= (1 << (CodeCompletionContext::CCC_UnionTag - 1));
194      else
195        Contexts |= (1 << (CodeCompletionContext::CCC_ClassOrStructTag - 1));
196
197      if (LangOpts.CPlusPlus)
198        IsNestedNameSpecifier = true;
199    } else if (isa<ClassTemplateDecl>(ND))
200      IsNestedNameSpecifier = true;
201  } else if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) {
202    // Values can appear in these contexts.
203    Contexts = (1 << (CodeCompletionContext::CCC_Statement - 1))
204             | (1 << (CodeCompletionContext::CCC_Expression - 1))
205             | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1))
206             | (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1));
207  } else if (isa<ObjCProtocolDecl>(ND)) {
208    Contexts = (1 << (CodeCompletionContext::CCC_ObjCProtocolName - 1));
209  } else if (isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND)) {
210    Contexts = (1 << (CodeCompletionContext::CCC_Namespace - 1));
211
212    // Part of the nested-name-specifier.
213    IsNestedNameSpecifier = true;
214  }
215
216  return Contexts;
217}
218
219void ASTUnit::CacheCodeCompletionResults() {
220  if (!TheSema)
221    return;
222
223  SimpleTimer Timer(WantTiming);
224  Timer.setOutput("Cache global code completions for " + getMainFileName());
225
226  // Clear out the previous results.
227  ClearCachedCompletionResults();
228
229  // Gather the set of global code completions.
230  typedef CodeCompletionResult Result;
231  llvm::SmallVector<Result, 8> Results;
232  CachedCompletionAllocator = new GlobalCodeCompletionAllocator;
233  TheSema->GatherGlobalCodeCompletions(*CachedCompletionAllocator, Results);
234
235  // Translate global code completions into cached completions.
236  llvm::DenseMap<CanQualType, unsigned> CompletionTypes;
237
238  for (unsigned I = 0, N = Results.size(); I != N; ++I) {
239    switch (Results[I].Kind) {
240    case Result::RK_Declaration: {
241      bool IsNestedNameSpecifier = false;
242      CachedCodeCompletionResult CachedResult;
243      CachedResult.Completion = Results[I].CreateCodeCompletionString(*TheSema,
244                                                    *CachedCompletionAllocator);
245      CachedResult.ShowInContexts = getDeclShowContexts(Results[I].Declaration,
246                                                        Ctx->getLangOptions(),
247                                                        IsNestedNameSpecifier);
248      CachedResult.Priority = Results[I].Priority;
249      CachedResult.Kind = Results[I].CursorKind;
250      CachedResult.Availability = Results[I].Availability;
251
252      // Keep track of the type of this completion in an ASTContext-agnostic
253      // way.
254      QualType UsageType = getDeclUsageType(*Ctx, Results[I].Declaration);
255      if (UsageType.isNull()) {
256        CachedResult.TypeClass = STC_Void;
257        CachedResult.Type = 0;
258      } else {
259        CanQualType CanUsageType
260          = Ctx->getCanonicalType(UsageType.getUnqualifiedType());
261        CachedResult.TypeClass = getSimplifiedTypeClass(CanUsageType);
262
263        // Determine whether we have already seen this type. If so, we save
264        // ourselves the work of formatting the type string by using the
265        // temporary, CanQualType-based hash table to find the associated value.
266        unsigned &TypeValue = CompletionTypes[CanUsageType];
267        if (TypeValue == 0) {
268          TypeValue = CompletionTypes.size();
269          CachedCompletionTypes[QualType(CanUsageType).getAsString()]
270            = TypeValue;
271        }
272
273        CachedResult.Type = TypeValue;
274      }
275
276      CachedCompletionResults.push_back(CachedResult);
277
278      /// Handle nested-name-specifiers in C++.
279      if (TheSema->Context.getLangOptions().CPlusPlus &&
280          IsNestedNameSpecifier && !Results[I].StartsNestedNameSpecifier) {
281        // The contexts in which a nested-name-specifier can appear in C++.
282        unsigned NNSContexts
283          = (1 << (CodeCompletionContext::CCC_TopLevel - 1))
284          | (1 << (CodeCompletionContext::CCC_ObjCIvarList - 1))
285          | (1 << (CodeCompletionContext::CCC_ClassStructUnion - 1))
286          | (1 << (CodeCompletionContext::CCC_Statement - 1))
287          | (1 << (CodeCompletionContext::CCC_Expression - 1))
288          | (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1))
289          | (1 << (CodeCompletionContext::CCC_EnumTag - 1))
290          | (1 << (CodeCompletionContext::CCC_UnionTag - 1))
291          | (1 << (CodeCompletionContext::CCC_ClassOrStructTag - 1))
292          | (1 << (CodeCompletionContext::CCC_Type - 1))
293          | (1 << (CodeCompletionContext::CCC_PotentiallyQualifiedName - 1))
294          | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1));
295
296        if (isa<NamespaceDecl>(Results[I].Declaration) ||
297            isa<NamespaceAliasDecl>(Results[I].Declaration))
298          NNSContexts |= (1 << (CodeCompletionContext::CCC_Namespace - 1));
299
300        if (unsigned RemainingContexts
301                                = NNSContexts & ~CachedResult.ShowInContexts) {
302          // If there any contexts where this completion can be a
303          // nested-name-specifier but isn't already an option, create a
304          // nested-name-specifier completion.
305          Results[I].StartsNestedNameSpecifier = true;
306          CachedResult.Completion
307            = Results[I].CreateCodeCompletionString(*TheSema,
308                                                    *CachedCompletionAllocator);
309          CachedResult.ShowInContexts = RemainingContexts;
310          CachedResult.Priority = CCP_NestedNameSpecifier;
311          CachedResult.TypeClass = STC_Void;
312          CachedResult.Type = 0;
313          CachedCompletionResults.push_back(CachedResult);
314        }
315      }
316      break;
317    }
318
319    case Result::RK_Keyword:
320    case Result::RK_Pattern:
321      // Ignore keywords and patterns; we don't care, since they are so
322      // easily regenerated.
323      break;
324
325    case Result::RK_Macro: {
326      CachedCodeCompletionResult CachedResult;
327      CachedResult.Completion
328        = Results[I].CreateCodeCompletionString(*TheSema,
329                                                *CachedCompletionAllocator);
330      CachedResult.ShowInContexts
331        = (1 << (CodeCompletionContext::CCC_TopLevel - 1))
332        | (1 << (CodeCompletionContext::CCC_ObjCInterface - 1))
333        | (1 << (CodeCompletionContext::CCC_ObjCImplementation - 1))
334        | (1 << (CodeCompletionContext::CCC_ObjCIvarList - 1))
335        | (1 << (CodeCompletionContext::CCC_ClassStructUnion - 1))
336        | (1 << (CodeCompletionContext::CCC_Statement - 1))
337        | (1 << (CodeCompletionContext::CCC_Expression - 1))
338        | (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1))
339        | (1 << (CodeCompletionContext::CCC_MacroNameUse - 1))
340        | (1 << (CodeCompletionContext::CCC_PreprocessorExpression - 1))
341        | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1))
342        | (1 << (CodeCompletionContext::CCC_OtherWithMacros - 1));
343
344      CachedResult.Priority = Results[I].Priority;
345      CachedResult.Kind = Results[I].CursorKind;
346      CachedResult.Availability = Results[I].Availability;
347      CachedResult.TypeClass = STC_Void;
348      CachedResult.Type = 0;
349      CachedCompletionResults.push_back(CachedResult);
350      break;
351    }
352    }
353  }
354
355  // Save the current top-level hash value.
356  CompletionCacheTopLevelHashValue = CurrentTopLevelHashValue;
357}
358
359void ASTUnit::ClearCachedCompletionResults() {
360  CachedCompletionResults.clear();
361  CachedCompletionTypes.clear();
362  CachedCompletionAllocator = 0;
363}
364
365namespace {
366
367/// \brief Gathers information from ASTReader that will be used to initialize
368/// a Preprocessor.
369class ASTInfoCollector : public ASTReaderListener {
370  LangOptions &LangOpt;
371  HeaderSearch &HSI;
372  std::string &TargetTriple;
373  std::string &Predefines;
374  unsigned &Counter;
375
376  unsigned NumHeaderInfos;
377
378public:
379  ASTInfoCollector(LangOptions &LangOpt, HeaderSearch &HSI,
380                   std::string &TargetTriple, std::string &Predefines,
381                   unsigned &Counter)
382    : LangOpt(LangOpt), HSI(HSI), TargetTriple(TargetTriple),
383      Predefines(Predefines), Counter(Counter), NumHeaderInfos(0) {}
384
385  virtual bool ReadLanguageOptions(const LangOptions &LangOpts) {
386    LangOpt = LangOpts;
387    return false;
388  }
389
390  virtual bool ReadTargetTriple(llvm::StringRef Triple) {
391    TargetTriple = Triple;
392    return false;
393  }
394
395  virtual bool ReadPredefinesBuffer(const PCHPredefinesBlocks &Buffers,
396                                    llvm::StringRef OriginalFileName,
397                                    std::string &SuggestedPredefines,
398                                    FileManager &FileMgr) {
399    Predefines = Buffers[0].Data;
400    for (unsigned I = 1, N = Buffers.size(); I != N; ++I) {
401      Predefines += Buffers[I].Data;
402    }
403    return false;
404  }
405
406  virtual void ReadHeaderFileInfo(const HeaderFileInfo &HFI, unsigned ID) {
407    HSI.setHeaderFileInfoForUID(HFI, NumHeaderInfos++);
408  }
409
410  virtual void ReadCounter(unsigned Value) {
411    Counter = Value;
412  }
413};
414
415class StoredDiagnosticClient : public DiagnosticClient {
416  llvm::SmallVectorImpl<StoredDiagnostic> &StoredDiags;
417
418public:
419  explicit StoredDiagnosticClient(
420                          llvm::SmallVectorImpl<StoredDiagnostic> &StoredDiags)
421    : StoredDiags(StoredDiags) { }
422
423  virtual void HandleDiagnostic(Diagnostic::Level Level,
424                                const DiagnosticInfo &Info);
425};
426
427/// \brief RAII object that optionally captures diagnostics, if
428/// there is no diagnostic client to capture them already.
429class CaptureDroppedDiagnostics {
430  Diagnostic &Diags;
431  StoredDiagnosticClient Client;
432  DiagnosticClient *PreviousClient;
433
434public:
435  CaptureDroppedDiagnostics(bool RequestCapture, Diagnostic &Diags,
436                          llvm::SmallVectorImpl<StoredDiagnostic> &StoredDiags)
437    : Diags(Diags), Client(StoredDiags), PreviousClient(0)
438  {
439    if (RequestCapture || Diags.getClient() == 0) {
440      PreviousClient = Diags.takeClient();
441      Diags.setClient(&Client);
442    }
443  }
444
445  ~CaptureDroppedDiagnostics() {
446    if (Diags.getClient() == &Client) {
447      Diags.takeClient();
448      Diags.setClient(PreviousClient);
449    }
450  }
451};
452
453} // anonymous namespace
454
455void StoredDiagnosticClient::HandleDiagnostic(Diagnostic::Level Level,
456                                              const DiagnosticInfo &Info) {
457  // Default implementation (Warnings/errors count).
458  DiagnosticClient::HandleDiagnostic(Level, Info);
459
460  StoredDiags.push_back(StoredDiagnostic(Level, Info));
461}
462
463const std::string &ASTUnit::getOriginalSourceFileName() {
464  return OriginalSourceFile;
465}
466
467const std::string &ASTUnit::getASTFileName() {
468  assert(isMainFileAST() && "Not an ASTUnit from an AST file!");
469  return static_cast<ASTReader *>(Ctx->getExternalSource())->getFileName();
470}
471
472llvm::MemoryBuffer *ASTUnit::getBufferForFile(llvm::StringRef Filename,
473                                              std::string *ErrorStr) {
474  assert(FileMgr);
475  return FileMgr->getBufferForFile(Filename, ErrorStr);
476}
477
478/// \brief Configure the diagnostics object for use with ASTUnit.
479void ASTUnit::ConfigureDiags(llvm::IntrusiveRefCntPtr<Diagnostic> &Diags,
480                             const char **ArgBegin, const char **ArgEnd,
481                             ASTUnit &AST, bool CaptureDiagnostics) {
482  if (!Diags.getPtr()) {
483    // No diagnostics engine was provided, so create our own diagnostics object
484    // with the default options.
485    DiagnosticOptions DiagOpts;
486    DiagnosticClient *Client = 0;
487    if (CaptureDiagnostics)
488      Client = new StoredDiagnosticClient(AST.StoredDiagnostics);
489    Diags = CompilerInstance::createDiagnostics(DiagOpts, ArgEnd- ArgBegin,
490                                                ArgBegin, Client);
491  } else if (CaptureDiagnostics) {
492    Diags->setClient(new StoredDiagnosticClient(AST.StoredDiagnostics));
493  }
494}
495
496ASTUnit *ASTUnit::LoadFromASTFile(const std::string &Filename,
497                                  llvm::IntrusiveRefCntPtr<Diagnostic> Diags,
498                                  const FileSystemOptions &FileSystemOpts,
499                                  bool OnlyLocalDecls,
500                                  RemappedFile *RemappedFiles,
501                                  unsigned NumRemappedFiles,
502                                  bool CaptureDiagnostics) {
503  llvm::OwningPtr<ASTUnit> AST(new ASTUnit(true));
504
505  // Recover resources if we crash before exiting this method.
506  llvm::CrashRecoveryContextCleanupRegistrar
507    ASTUnitCleanup(llvm::CrashRecoveryContextCleanup::
508                    create<ASTUnit>(AST.get()));
509
510  ConfigureDiags(Diags, 0, 0, *AST, CaptureDiagnostics);
511
512  AST->OnlyLocalDecls = OnlyLocalDecls;
513  AST->CaptureDiagnostics = CaptureDiagnostics;
514  AST->Diagnostics = Diags;
515  AST->FileMgr.reset(new FileManager(FileSystemOpts));
516  AST->SourceMgr.reset(new SourceManager(AST->getDiagnostics(),
517                                         AST->getFileManager()));
518  AST->HeaderInfo.reset(new HeaderSearch(AST->getFileManager()));
519
520  for (unsigned I = 0; I != NumRemappedFiles; ++I) {
521    FilenameOrMemBuf fileOrBuf = RemappedFiles[I].second;
522    if (const llvm::MemoryBuffer *
523          memBuf = fileOrBuf.dyn_cast<const llvm::MemoryBuffer *>()) {
524      // Create the file entry for the file that we're mapping from.
525      const FileEntry *FromFile
526        = AST->getFileManager().getVirtualFile(RemappedFiles[I].first,
527                                               memBuf->getBufferSize(),
528                                               0);
529      if (!FromFile) {
530        AST->getDiagnostics().Report(diag::err_fe_remap_missing_from_file)
531          << RemappedFiles[I].first;
532        delete memBuf;
533        continue;
534      }
535
536      // Override the contents of the "from" file with the contents of
537      // the "to" file.
538      AST->getSourceManager().overrideFileContents(FromFile, memBuf);
539
540    } else {
541      const char *fname = fileOrBuf.get<const char *>();
542      const FileEntry *ToFile = AST->FileMgr->getFile(fname);
543      if (!ToFile) {
544        AST->getDiagnostics().Report(diag::err_fe_remap_missing_to_file)
545        << RemappedFiles[I].first << fname;
546        continue;
547      }
548
549      // Create the file entry for the file that we're mapping from.
550      const FileEntry *FromFile
551        = AST->getFileManager().getVirtualFile(RemappedFiles[I].first,
552                                               ToFile->getSize(),
553                                               0);
554      if (!FromFile) {
555        AST->getDiagnostics().Report(diag::err_fe_remap_missing_from_file)
556          << RemappedFiles[I].first;
557        delete memBuf;
558        continue;
559      }
560
561      // Override the contents of the "from" file with the contents of
562      // the "to" file.
563      AST->getSourceManager().overrideFileContents(FromFile, ToFile);
564    }
565  }
566
567  // Gather Info for preprocessor construction later on.
568
569  LangOptions LangInfo;
570  HeaderSearch &HeaderInfo = *AST->HeaderInfo.get();
571  std::string TargetTriple;
572  std::string Predefines;
573  unsigned Counter;
574
575  llvm::OwningPtr<ASTReader> Reader;
576
577  Reader.reset(new ASTReader(AST->getSourceManager(), AST->getFileManager(),
578                             AST->getDiagnostics()));
579  Reader->setListener(new ASTInfoCollector(LangInfo, HeaderInfo, TargetTriple,
580                                           Predefines, Counter));
581
582  switch (Reader->ReadAST(Filename, ASTReader::MainFile)) {
583  case ASTReader::Success:
584    break;
585
586  case ASTReader::Failure:
587  case ASTReader::IgnorePCH:
588    AST->getDiagnostics().Report(diag::err_fe_unable_to_load_pch);
589    return NULL;
590  }
591
592  AST->OriginalSourceFile = Reader->getOriginalSourceFile();
593
594  // AST file loaded successfully. Now create the preprocessor.
595
596  // Get information about the target being compiled for.
597  //
598  // FIXME: This is broken, we should store the TargetOptions in the AST file.
599  TargetOptions TargetOpts;
600  TargetOpts.ABI = "";
601  TargetOpts.CXXABI = "";
602  TargetOpts.CPU = "";
603  TargetOpts.Features.clear();
604  TargetOpts.Triple = TargetTriple;
605  AST->Target.reset(TargetInfo::CreateTargetInfo(AST->getDiagnostics(),
606                                                 TargetOpts));
607  AST->PP.reset(new Preprocessor(AST->getDiagnostics(), LangInfo,
608                                 *AST->Target.get(),
609                                 AST->getSourceManager(), HeaderInfo));
610  Preprocessor &PP = *AST->PP.get();
611
612  PP.setPredefines(Reader->getSuggestedPredefines());
613  PP.setCounterValue(Counter);
614  Reader->setPreprocessor(PP);
615
616  // Create and initialize the ASTContext.
617
618  AST->Ctx.reset(new ASTContext(LangInfo,
619                                AST->getSourceManager(),
620                                *AST->Target.get(),
621                                PP.getIdentifierTable(),
622                                PP.getSelectorTable(),
623                                PP.getBuiltinInfo(),
624                                /* size_reserve = */0));
625  ASTContext &Context = *AST->Ctx.get();
626
627  Reader->InitializeContext(Context);
628
629  // Attach the AST reader to the AST context as an external AST
630  // source, so that declarations will be deserialized from the
631  // AST file as needed.
632  ASTReader *ReaderPtr = Reader.get();
633  llvm::OwningPtr<ExternalASTSource> Source(Reader.take());
634  Context.setExternalSource(Source);
635
636  // Create an AST consumer, even though it isn't used.
637  AST->Consumer.reset(new ASTConsumer);
638
639  // Create a semantic analysis object and tell the AST reader about it.
640  AST->TheSema.reset(new Sema(PP, Context, *AST->Consumer));
641  AST->TheSema->Initialize();
642  ReaderPtr->InitializeSema(*AST->TheSema);
643
644  return AST.take();
645}
646
647namespace {
648
649/// \brief Preprocessor callback class that updates a hash value with the names
650/// of all macros that have been defined by the translation unit.
651class MacroDefinitionTrackerPPCallbacks : public PPCallbacks {
652  unsigned &Hash;
653
654public:
655  explicit MacroDefinitionTrackerPPCallbacks(unsigned &Hash) : Hash(Hash) { }
656
657  virtual void MacroDefined(const Token &MacroNameTok, const MacroInfo *MI) {
658    Hash = llvm::HashString(MacroNameTok.getIdentifierInfo()->getName(), Hash);
659  }
660};
661
662/// \brief Add the given declaration to the hash of all top-level entities.
663void AddTopLevelDeclarationToHash(Decl *D, unsigned &Hash) {
664  if (!D)
665    return;
666
667  DeclContext *DC = D->getDeclContext();
668  if (!DC)
669    return;
670
671  if (!(DC->isTranslationUnit() || DC->getLookupParent()->isTranslationUnit()))
672    return;
673
674  if (NamedDecl *ND = dyn_cast<NamedDecl>(D)) {
675    if (ND->getIdentifier())
676      Hash = llvm::HashString(ND->getIdentifier()->getName(), Hash);
677    else if (DeclarationName Name = ND->getDeclName()) {
678      std::string NameStr = Name.getAsString();
679      Hash = llvm::HashString(NameStr, Hash);
680    }
681    return;
682  }
683
684  if (ObjCForwardProtocolDecl *Forward
685      = dyn_cast<ObjCForwardProtocolDecl>(D)) {
686    for (ObjCForwardProtocolDecl::protocol_iterator
687         P = Forward->protocol_begin(),
688         PEnd = Forward->protocol_end();
689         P != PEnd; ++P)
690      AddTopLevelDeclarationToHash(*P, Hash);
691    return;
692  }
693
694  if (ObjCClassDecl *Class = llvm::dyn_cast<ObjCClassDecl>(D)) {
695    for (ObjCClassDecl::iterator I = Class->begin(), IEnd = Class->end();
696         I != IEnd; ++I)
697      AddTopLevelDeclarationToHash(I->getInterface(), Hash);
698    return;
699  }
700}
701
702class TopLevelDeclTrackerConsumer : public ASTConsumer {
703  ASTUnit &Unit;
704  unsigned &Hash;
705
706public:
707  TopLevelDeclTrackerConsumer(ASTUnit &_Unit, unsigned &Hash)
708    : Unit(_Unit), Hash(Hash) {
709    Hash = 0;
710  }
711
712  void HandleTopLevelDecl(DeclGroupRef D) {
713    for (DeclGroupRef::iterator it = D.begin(), ie = D.end(); it != ie; ++it) {
714      Decl *D = *it;
715      // FIXME: Currently ObjC method declarations are incorrectly being
716      // reported as top-level declarations, even though their DeclContext
717      // is the containing ObjC @interface/@implementation.  This is a
718      // fundamental problem in the parser right now.
719      if (isa<ObjCMethodDecl>(D))
720        continue;
721
722      AddTopLevelDeclarationToHash(D, Hash);
723      Unit.addTopLevelDecl(D);
724    }
725  }
726
727  // We're not interested in "interesting" decls.
728  void HandleInterestingDecl(DeclGroupRef) {}
729};
730
731class TopLevelDeclTrackerAction : public ASTFrontendAction {
732public:
733  ASTUnit &Unit;
734
735  virtual ASTConsumer *CreateASTConsumer(CompilerInstance &CI,
736                                         llvm::StringRef InFile) {
737    CI.getPreprocessor().addPPCallbacks(
738     new MacroDefinitionTrackerPPCallbacks(Unit.getCurrentTopLevelHashValue()));
739    return new TopLevelDeclTrackerConsumer(Unit,
740                                           Unit.getCurrentTopLevelHashValue());
741  }
742
743public:
744  TopLevelDeclTrackerAction(ASTUnit &_Unit) : Unit(_Unit) {}
745
746  virtual bool hasCodeCompletionSupport() const { return false; }
747  virtual bool usesCompleteTranslationUnit()  {
748    return Unit.isCompleteTranslationUnit();
749  }
750};
751
752class PrecompilePreambleConsumer : public PCHGenerator,
753                                   public ASTSerializationListener {
754  ASTUnit &Unit;
755  unsigned &Hash;
756  std::vector<Decl *> TopLevelDecls;
757
758public:
759  PrecompilePreambleConsumer(ASTUnit &Unit,
760                             const Preprocessor &PP, bool Chaining,
761                             const char *isysroot, llvm::raw_ostream *Out)
762    : PCHGenerator(PP, "", Chaining, isysroot, Out), Unit(Unit),
763      Hash(Unit.getCurrentTopLevelHashValue()) {
764    Hash = 0;
765  }
766
767  virtual void HandleTopLevelDecl(DeclGroupRef D) {
768    for (DeclGroupRef::iterator it = D.begin(), ie = D.end(); it != ie; ++it) {
769      Decl *D = *it;
770      // FIXME: Currently ObjC method declarations are incorrectly being
771      // reported as top-level declarations, even though their DeclContext
772      // is the containing ObjC @interface/@implementation.  This is a
773      // fundamental problem in the parser right now.
774      if (isa<ObjCMethodDecl>(D))
775        continue;
776      AddTopLevelDeclarationToHash(D, Hash);
777      TopLevelDecls.push_back(D);
778    }
779  }
780
781  virtual void HandleTranslationUnit(ASTContext &Ctx) {
782    PCHGenerator::HandleTranslationUnit(Ctx);
783    if (!Unit.getDiagnostics().hasErrorOccurred()) {
784      // Translate the top-level declarations we captured during
785      // parsing into declaration IDs in the precompiled
786      // preamble. This will allow us to deserialize those top-level
787      // declarations when requested.
788      for (unsigned I = 0, N = TopLevelDecls.size(); I != N; ++I)
789        Unit.addTopLevelDeclFromPreamble(
790                                      getWriter().getDeclID(TopLevelDecls[I]));
791    }
792  }
793
794  virtual void SerializedPreprocessedEntity(PreprocessedEntity *Entity,
795                                            uint64_t Offset) {
796    Unit.addPreprocessedEntityFromPreamble(Offset);
797  }
798
799  virtual ASTSerializationListener *GetASTSerializationListener() {
800    return this;
801  }
802};
803
804class PrecompilePreambleAction : public ASTFrontendAction {
805  ASTUnit &Unit;
806
807public:
808  explicit PrecompilePreambleAction(ASTUnit &Unit) : Unit(Unit) {}
809
810  virtual ASTConsumer *CreateASTConsumer(CompilerInstance &CI,
811                                         llvm::StringRef InFile) {
812    std::string Sysroot;
813    std::string OutputFile;
814    llvm::raw_ostream *OS = 0;
815    bool Chaining;
816    if (GeneratePCHAction::ComputeASTConsumerArguments(CI, InFile, Sysroot,
817                                                       OutputFile,
818                                                       OS, Chaining))
819      return 0;
820
821    const char *isysroot = CI.getFrontendOpts().RelocatablePCH ?
822                             Sysroot.c_str() : 0;
823    CI.getPreprocessor().addPPCallbacks(
824     new MacroDefinitionTrackerPPCallbacks(Unit.getCurrentTopLevelHashValue()));
825    return new PrecompilePreambleConsumer(Unit, CI.getPreprocessor(), Chaining,
826                                          isysroot, OS);
827  }
828
829  virtual bool hasCodeCompletionSupport() const { return false; }
830  virtual bool hasASTFileSupport() const { return false; }
831  virtual bool usesCompleteTranslationUnit() { return false; }
832};
833
834}
835
836/// Parse the source file into a translation unit using the given compiler
837/// invocation, replacing the current translation unit.
838///
839/// \returns True if a failure occurred that causes the ASTUnit not to
840/// contain any translation-unit information, false otherwise.
841bool ASTUnit::Parse(llvm::MemoryBuffer *OverrideMainBuffer) {
842  delete SavedMainFileBuffer;
843  SavedMainFileBuffer = 0;
844
845  if (!Invocation.get()) {
846    delete OverrideMainBuffer;
847    return true;
848  }
849
850  // Create the compiler instance to use for building the AST.
851  llvm::OwningPtr<CompilerInstance> Clang(new CompilerInstance());
852
853  // Recover resources if we crash before exiting this method.
854  llvm::CrashRecoveryContextCleanupRegistrar
855    CICleanup(llvm::CrashRecoveryContextCleanup::
856                    create<CompilerInstance>(Clang.get()));
857
858  Clang->setInvocation(Invocation.take());
859  OriginalSourceFile = Clang->getFrontendOpts().Inputs[0].second;
860
861  // Set up diagnostics, capturing any diagnostics that would
862  // otherwise be dropped.
863  Clang->setDiagnostics(&getDiagnostics());
864
865  // Create the target instance.
866  Clang->getTargetOpts().Features = TargetFeatures;
867  Clang->setTarget(TargetInfo::CreateTargetInfo(Clang->getDiagnostics(),
868						Clang->getTargetOpts()));
869  if (!Clang->hasTarget()) {
870    delete OverrideMainBuffer;
871    return true;
872  }
873
874  // Inform the target of the language options.
875  //
876  // FIXME: We shouldn't need to do this, the target should be immutable once
877  // created. This complexity should be lifted elsewhere.
878  Clang->getTarget().setForcedLangOptions(Clang->getLangOpts());
879
880  assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
881         "Invocation must have exactly one source file!");
882  assert(Clang->getFrontendOpts().Inputs[0].first != IK_AST &&
883         "FIXME: AST inputs not yet supported here!");
884  assert(Clang->getFrontendOpts().Inputs[0].first != IK_LLVM_IR &&
885         "IR inputs not support here!");
886
887  // Configure the various subsystems.
888  // FIXME: Should we retain the previous file manager?
889  FileSystemOpts = Clang->getFileSystemOpts();
890  FileMgr.reset(new FileManager(FileSystemOpts));
891  SourceMgr.reset(new SourceManager(getDiagnostics(), *FileMgr));
892  TheSema.reset();
893  Ctx.reset();
894  PP.reset();
895
896  // Clear out old caches and data.
897  TopLevelDecls.clear();
898  PreprocessedEntities.clear();
899  CleanTemporaryFiles();
900  PreprocessedEntitiesByFile.clear();
901
902  if (!OverrideMainBuffer) {
903    StoredDiagnostics.erase(
904                    StoredDiagnostics.begin() + NumStoredDiagnosticsFromDriver,
905                            StoredDiagnostics.end());
906    TopLevelDeclsInPreamble.clear();
907    PreprocessedEntitiesInPreamble.clear();
908  }
909
910  // Create a file manager object to provide access to and cache the filesystem.
911  Clang->setFileManager(&getFileManager());
912
913  // Create the source manager.
914  Clang->setSourceManager(&getSourceManager());
915
916  // If the main file has been overridden due to the use of a preamble,
917  // make that override happen and introduce the preamble.
918  PreprocessorOptions &PreprocessorOpts = Clang->getPreprocessorOpts();
919  std::string PriorImplicitPCHInclude;
920  if (OverrideMainBuffer) {
921    PreprocessorOpts.addRemappedFile(OriginalSourceFile, OverrideMainBuffer);
922    PreprocessorOpts.PrecompiledPreambleBytes.first = Preamble.size();
923    PreprocessorOpts.PrecompiledPreambleBytes.second
924                                                    = PreambleEndsAtStartOfLine;
925    PriorImplicitPCHInclude = PreprocessorOpts.ImplicitPCHInclude;
926    PreprocessorOpts.ImplicitPCHInclude = PreambleFile;
927    PreprocessorOpts.DisablePCHValidation = true;
928
929    // The stored diagnostic has the old source manager in it; update
930    // the locations to refer into the new source manager. Since we've
931    // been careful to make sure that the source manager's state
932    // before and after are identical, so that we can reuse the source
933    // location itself.
934    for (unsigned I = NumStoredDiagnosticsFromDriver,
935                  N = StoredDiagnostics.size();
936         I < N; ++I) {
937      FullSourceLoc Loc(StoredDiagnostics[I].getLocation(),
938                        getSourceManager());
939      StoredDiagnostics[I].setLocation(Loc);
940    }
941
942    // Keep track of the override buffer;
943    SavedMainFileBuffer = OverrideMainBuffer;
944  } else {
945    PreprocessorOpts.PrecompiledPreambleBytes.first = 0;
946    PreprocessorOpts.PrecompiledPreambleBytes.second = false;
947  }
948
949  llvm::OwningPtr<TopLevelDeclTrackerAction> Act;
950  Act.reset(new TopLevelDeclTrackerAction(*this));
951  if (!Act->BeginSourceFile(*Clang.get(), Clang->getFrontendOpts().Inputs[0].second,
952                            Clang->getFrontendOpts().Inputs[0].first))
953    goto error;
954
955  Act->Execute();
956
957  // Steal the created target, context, and preprocessor, and take back the
958  // source and file managers.
959  TheSema.reset(Clang->takeSema());
960  Consumer.reset(Clang->takeASTConsumer());
961  Ctx.reset(Clang->takeASTContext());
962  PP.reset(Clang->takePreprocessor());
963  Clang->takeSourceManager();
964  Clang->takeFileManager();
965  Target.reset(Clang->takeTarget());
966
967  Act->EndSourceFile();
968
969  // Remove the overridden buffer we used for the preamble.
970  if (OverrideMainBuffer) {
971    PreprocessorOpts.eraseRemappedFile(
972                               PreprocessorOpts.remapped_file_buffer_end() - 1);
973    PreprocessorOpts.ImplicitPCHInclude = PriorImplicitPCHInclude;
974  }
975
976  Invocation.reset(Clang->takeInvocation());
977  return false;
978
979error:
980  // Remove the overridden buffer we used for the preamble.
981  if (OverrideMainBuffer) {
982    PreprocessorOpts.eraseRemappedFile(
983                               PreprocessorOpts.remapped_file_buffer_end() - 1);
984    PreprocessorOpts.ImplicitPCHInclude = PriorImplicitPCHInclude;
985    delete OverrideMainBuffer;
986    SavedMainFileBuffer = 0;
987  }
988
989  StoredDiagnostics.clear();
990  Clang->takeSourceManager();
991  Clang->takeFileManager();
992  Invocation.reset(Clang->takeInvocation());
993  return true;
994}
995
996/// \brief Simple function to retrieve a path for a preamble precompiled header.
997static std::string GetPreamblePCHPath() {
998  // FIXME: This is lame; sys::Path should provide this function (in particular,
999  // it should know how to find the temporary files dir).
1000  // FIXME: This is really lame. I copied this code from the Driver!
1001  // FIXME: This is a hack so that we can override the preamble file during
1002  // crash-recovery testing, which is the only case where the preamble files
1003  // are not necessarily cleaned up.
1004  const char *TmpFile = ::getenv("CINDEXTEST_PREAMBLE_FILE");
1005  if (TmpFile)
1006    return TmpFile;
1007
1008  std::string Error;
1009  const char *TmpDir = ::getenv("TMPDIR");
1010  if (!TmpDir)
1011    TmpDir = ::getenv("TEMP");
1012  if (!TmpDir)
1013    TmpDir = ::getenv("TMP");
1014#ifdef LLVM_ON_WIN32
1015  if (!TmpDir)
1016    TmpDir = ::getenv("USERPROFILE");
1017#endif
1018  if (!TmpDir)
1019    TmpDir = "/tmp";
1020  llvm::sys::Path P(TmpDir);
1021  P.createDirectoryOnDisk(true);
1022  P.appendComponent("preamble");
1023  P.appendSuffix("pch");
1024  if (P.createTemporaryFileOnDisk())
1025    return std::string();
1026
1027  return P.str();
1028}
1029
1030/// \brief Compute the preamble for the main file, providing the source buffer
1031/// that corresponds to the main file along with a pair (bytes, start-of-line)
1032/// that describes the preamble.
1033std::pair<llvm::MemoryBuffer *, std::pair<unsigned, bool> >
1034ASTUnit::ComputePreamble(CompilerInvocation &Invocation,
1035                         unsigned MaxLines, bool &CreatedBuffer) {
1036  FrontendOptions &FrontendOpts = Invocation.getFrontendOpts();
1037  PreprocessorOptions &PreprocessorOpts = Invocation.getPreprocessorOpts();
1038  CreatedBuffer = false;
1039
1040  // Try to determine if the main file has been remapped, either from the
1041  // command line (to another file) or directly through the compiler invocation
1042  // (to a memory buffer).
1043  llvm::MemoryBuffer *Buffer = 0;
1044  llvm::sys::PathWithStatus MainFilePath(FrontendOpts.Inputs[0].second);
1045  if (const llvm::sys::FileStatus *MainFileStatus = MainFilePath.getFileStatus()) {
1046    // Check whether there is a file-file remapping of the main file
1047    for (PreprocessorOptions::remapped_file_iterator
1048          M = PreprocessorOpts.remapped_file_begin(),
1049          E = PreprocessorOpts.remapped_file_end();
1050         M != E;
1051         ++M) {
1052      llvm::sys::PathWithStatus MPath(M->first);
1053      if (const llvm::sys::FileStatus *MStatus = MPath.getFileStatus()) {
1054        if (MainFileStatus->uniqueID == MStatus->uniqueID) {
1055          // We found a remapping. Try to load the resulting, remapped source.
1056          if (CreatedBuffer) {
1057            delete Buffer;
1058            CreatedBuffer = false;
1059          }
1060
1061          Buffer = getBufferForFile(M->second);
1062          if (!Buffer)
1063            return std::make_pair((llvm::MemoryBuffer*)0,
1064                                  std::make_pair(0, true));
1065          CreatedBuffer = true;
1066        }
1067      }
1068    }
1069
1070    // Check whether there is a file-buffer remapping. It supercedes the
1071    // file-file remapping.
1072    for (PreprocessorOptions::remapped_file_buffer_iterator
1073           M = PreprocessorOpts.remapped_file_buffer_begin(),
1074           E = PreprocessorOpts.remapped_file_buffer_end();
1075         M != E;
1076         ++M) {
1077      llvm::sys::PathWithStatus MPath(M->first);
1078      if (const llvm::sys::FileStatus *MStatus = MPath.getFileStatus()) {
1079        if (MainFileStatus->uniqueID == MStatus->uniqueID) {
1080          // We found a remapping.
1081          if (CreatedBuffer) {
1082            delete Buffer;
1083            CreatedBuffer = false;
1084          }
1085
1086          Buffer = const_cast<llvm::MemoryBuffer *>(M->second);
1087        }
1088      }
1089    }
1090  }
1091
1092  // If the main source file was not remapped, load it now.
1093  if (!Buffer) {
1094    Buffer = getBufferForFile(FrontendOpts.Inputs[0].second);
1095    if (!Buffer)
1096      return std::make_pair((llvm::MemoryBuffer*)0, std::make_pair(0, true));
1097
1098    CreatedBuffer = true;
1099  }
1100
1101  return std::make_pair(Buffer, Lexer::ComputePreamble(Buffer, MaxLines));
1102}
1103
1104static llvm::MemoryBuffer *CreatePaddedMainFileBuffer(llvm::MemoryBuffer *Old,
1105                                                      unsigned NewSize,
1106                                                      llvm::StringRef NewName) {
1107  llvm::MemoryBuffer *Result
1108    = llvm::MemoryBuffer::getNewUninitMemBuffer(NewSize, NewName);
1109  memcpy(const_cast<char*>(Result->getBufferStart()),
1110         Old->getBufferStart(), Old->getBufferSize());
1111  memset(const_cast<char*>(Result->getBufferStart()) + Old->getBufferSize(),
1112         ' ', NewSize - Old->getBufferSize() - 1);
1113  const_cast<char*>(Result->getBufferEnd())[-1] = '\n';
1114
1115  return Result;
1116}
1117
1118/// \brief Attempt to build or re-use a precompiled preamble when (re-)parsing
1119/// the source file.
1120///
1121/// This routine will compute the preamble of the main source file. If a
1122/// non-trivial preamble is found, it will precompile that preamble into a
1123/// precompiled header so that the precompiled preamble can be used to reduce
1124/// reparsing time. If a precompiled preamble has already been constructed,
1125/// this routine will determine if it is still valid and, if so, avoid
1126/// rebuilding the precompiled preamble.
1127///
1128/// \param AllowRebuild When true (the default), this routine is
1129/// allowed to rebuild the precompiled preamble if it is found to be
1130/// out-of-date.
1131///
1132/// \param MaxLines When non-zero, the maximum number of lines that
1133/// can occur within the preamble.
1134///
1135/// \returns If the precompiled preamble can be used, returns a newly-allocated
1136/// buffer that should be used in place of the main file when doing so.
1137/// Otherwise, returns a NULL pointer.
1138llvm::MemoryBuffer *ASTUnit::getMainBufferWithPrecompiledPreamble(
1139                                          CompilerInvocation PreambleInvocation,
1140                                                           bool AllowRebuild,
1141                                                           unsigned MaxLines) {
1142  FrontendOptions &FrontendOpts = PreambleInvocation.getFrontendOpts();
1143  PreprocessorOptions &PreprocessorOpts
1144    = PreambleInvocation.getPreprocessorOpts();
1145
1146  bool CreatedPreambleBuffer = false;
1147  std::pair<llvm::MemoryBuffer *, std::pair<unsigned, bool> > NewPreamble
1148    = ComputePreamble(PreambleInvocation, MaxLines, CreatedPreambleBuffer);
1149
1150  // If ComputePreamble() Take ownership of the
1151  llvm::OwningPtr<llvm::MemoryBuffer> OwnedPreambleBuffer;
1152  if (CreatedPreambleBuffer)
1153    OwnedPreambleBuffer.reset(NewPreamble.first);
1154
1155  if (!NewPreamble.second.first) {
1156    // We couldn't find a preamble in the main source. Clear out the current
1157    // preamble, if we have one. It's obviously no good any more.
1158    Preamble.clear();
1159    if (!PreambleFile.empty()) {
1160      llvm::sys::Path(PreambleFile).eraseFromDisk();
1161      PreambleFile.clear();
1162    }
1163
1164    // The next time we actually see a preamble, precompile it.
1165    PreambleRebuildCounter = 1;
1166    return 0;
1167  }
1168
1169  if (!Preamble.empty()) {
1170    // We've previously computed a preamble. Check whether we have the same
1171    // preamble now that we did before, and that there's enough space in
1172    // the main-file buffer within the precompiled preamble to fit the
1173    // new main file.
1174    if (Preamble.size() == NewPreamble.second.first &&
1175        PreambleEndsAtStartOfLine == NewPreamble.second.second &&
1176        NewPreamble.first->getBufferSize() < PreambleReservedSize-2 &&
1177        memcmp(&Preamble[0], NewPreamble.first->getBufferStart(),
1178               NewPreamble.second.first) == 0) {
1179      // The preamble has not changed. We may be able to re-use the precompiled
1180      // preamble.
1181
1182      // Check that none of the files used by the preamble have changed.
1183      bool AnyFileChanged = false;
1184
1185      // First, make a record of those files that have been overridden via
1186      // remapping or unsaved_files.
1187      llvm::StringMap<std::pair<off_t, time_t> > OverriddenFiles;
1188      for (PreprocessorOptions::remapped_file_iterator
1189                R = PreprocessorOpts.remapped_file_begin(),
1190             REnd = PreprocessorOpts.remapped_file_end();
1191           !AnyFileChanged && R != REnd;
1192           ++R) {
1193        struct stat StatBuf;
1194        if (FileMgr->getNoncachedStatValue(R->second, StatBuf)) {
1195          // If we can't stat the file we're remapping to, assume that something
1196          // horrible happened.
1197          AnyFileChanged = true;
1198          break;
1199        }
1200
1201        OverriddenFiles[R->first] = std::make_pair(StatBuf.st_size,
1202                                                   StatBuf.st_mtime);
1203      }
1204      for (PreprocessorOptions::remapped_file_buffer_iterator
1205                R = PreprocessorOpts.remapped_file_buffer_begin(),
1206             REnd = PreprocessorOpts.remapped_file_buffer_end();
1207           !AnyFileChanged && R != REnd;
1208           ++R) {
1209        // FIXME: Should we actually compare the contents of file->buffer
1210        // remappings?
1211        OverriddenFiles[R->first] = std::make_pair(R->second->getBufferSize(),
1212                                                   0);
1213      }
1214
1215      // Check whether anything has changed.
1216      for (llvm::StringMap<std::pair<off_t, time_t> >::iterator
1217             F = FilesInPreamble.begin(), FEnd = FilesInPreamble.end();
1218           !AnyFileChanged && F != FEnd;
1219           ++F) {
1220        llvm::StringMap<std::pair<off_t, time_t> >::iterator Overridden
1221          = OverriddenFiles.find(F->first());
1222        if (Overridden != OverriddenFiles.end()) {
1223          // This file was remapped; check whether the newly-mapped file
1224          // matches up with the previous mapping.
1225          if (Overridden->second != F->second)
1226            AnyFileChanged = true;
1227          continue;
1228        }
1229
1230        // The file was not remapped; check whether it has changed on disk.
1231        struct stat StatBuf;
1232        if (FileMgr->getNoncachedStatValue(F->first(), StatBuf)) {
1233          // If we can't stat the file, assume that something horrible happened.
1234          AnyFileChanged = true;
1235        } else if (StatBuf.st_size != F->second.first ||
1236                   StatBuf.st_mtime != F->second.second)
1237          AnyFileChanged = true;
1238      }
1239
1240      if (!AnyFileChanged) {
1241        // Okay! We can re-use the precompiled preamble.
1242
1243        // Set the state of the diagnostic object to mimic its state
1244        // after parsing the preamble.
1245        // FIXME: This won't catch any #pragma push warning changes that
1246        // have occurred in the preamble.
1247        getDiagnostics().Reset();
1248        ProcessWarningOptions(getDiagnostics(),
1249                              PreambleInvocation.getDiagnosticOpts());
1250        getDiagnostics().setNumWarnings(NumWarningsInPreamble);
1251        if (StoredDiagnostics.size() > NumStoredDiagnosticsInPreamble)
1252          StoredDiagnostics.erase(
1253            StoredDiagnostics.begin() + NumStoredDiagnosticsInPreamble,
1254                                  StoredDiagnostics.end());
1255
1256        // Create a version of the main file buffer that is padded to
1257        // buffer size we reserved when creating the preamble.
1258        return CreatePaddedMainFileBuffer(NewPreamble.first,
1259                                          PreambleReservedSize,
1260                                          FrontendOpts.Inputs[0].second);
1261      }
1262    }
1263
1264    // If we aren't allowed to rebuild the precompiled preamble, just
1265    // return now.
1266    if (!AllowRebuild)
1267      return 0;
1268
1269    // We can't reuse the previously-computed preamble. Build a new one.
1270    Preamble.clear();
1271    llvm::sys::Path(PreambleFile).eraseFromDisk();
1272    PreambleRebuildCounter = 1;
1273  } else if (!AllowRebuild) {
1274    // We aren't allowed to rebuild the precompiled preamble; just
1275    // return now.
1276    return 0;
1277  }
1278
1279  // If the preamble rebuild counter > 1, it's because we previously
1280  // failed to build a preamble and we're not yet ready to try
1281  // again. Decrement the counter and return a failure.
1282  if (PreambleRebuildCounter > 1) {
1283    --PreambleRebuildCounter;
1284    return 0;
1285  }
1286
1287  // Create a temporary file for the precompiled preamble. In rare
1288  // circumstances, this can fail.
1289  std::string PreamblePCHPath = GetPreamblePCHPath();
1290  if (PreamblePCHPath.empty()) {
1291    // Try again next time.
1292    PreambleRebuildCounter = 1;
1293    return 0;
1294  }
1295
1296  // We did not previously compute a preamble, or it can't be reused anyway.
1297  SimpleTimer PreambleTimer(WantTiming);
1298  PreambleTimer.setOutput("Precompiling preamble");
1299
1300  // Create a new buffer that stores the preamble. The buffer also contains
1301  // extra space for the original contents of the file (which will be present
1302  // when we actually parse the file) along with more room in case the file
1303  // grows.
1304  PreambleReservedSize = NewPreamble.first->getBufferSize();
1305  if (PreambleReservedSize < 4096)
1306    PreambleReservedSize = 8191;
1307  else
1308    PreambleReservedSize *= 2;
1309
1310  // Save the preamble text for later; we'll need to compare against it for
1311  // subsequent reparses.
1312  Preamble.assign(NewPreamble.first->getBufferStart(),
1313                  NewPreamble.first->getBufferStart()
1314                                                  + NewPreamble.second.first);
1315  PreambleEndsAtStartOfLine = NewPreamble.second.second;
1316
1317  delete PreambleBuffer;
1318  PreambleBuffer
1319    = llvm::MemoryBuffer::getNewUninitMemBuffer(PreambleReservedSize,
1320                                                FrontendOpts.Inputs[0].second);
1321  memcpy(const_cast<char*>(PreambleBuffer->getBufferStart()),
1322         NewPreamble.first->getBufferStart(), Preamble.size());
1323  memset(const_cast<char*>(PreambleBuffer->getBufferStart()) + Preamble.size(),
1324         ' ', PreambleReservedSize - Preamble.size() - 1);
1325  const_cast<char*>(PreambleBuffer->getBufferEnd())[-1] = '\n';
1326
1327  // Remap the main source file to the preamble buffer.
1328  llvm::sys::PathWithStatus MainFilePath(FrontendOpts.Inputs[0].second);
1329  PreprocessorOpts.addRemappedFile(MainFilePath.str(), PreambleBuffer);
1330
1331  // Tell the compiler invocation to generate a temporary precompiled header.
1332  FrontendOpts.ProgramAction = frontend::GeneratePCH;
1333  FrontendOpts.ChainedPCH = true;
1334  // FIXME: Generate the precompiled header into memory?
1335  FrontendOpts.OutputFile = PreamblePCHPath;
1336  PreprocessorOpts.PrecompiledPreambleBytes.first = 0;
1337  PreprocessorOpts.PrecompiledPreambleBytes.second = false;
1338
1339  // Create the compiler instance to use for building the precompiled preamble.
1340  llvm::OwningPtr<CompilerInstance> Clang(new CompilerInstance());
1341
1342  // Recover resources if we crash before exiting this method.
1343  llvm::CrashRecoveryContextCleanupRegistrar
1344    CICleanup(llvm::CrashRecoveryContextCleanup::
1345                    create<CompilerInstance>(Clang.get()));
1346
1347  Clang->setInvocation(&PreambleInvocation);
1348  OriginalSourceFile = Clang->getFrontendOpts().Inputs[0].second;
1349
1350  // Set up diagnostics, capturing all of the diagnostics produced.
1351  Clang->setDiagnostics(&getDiagnostics());
1352
1353  // Create the target instance.
1354  Clang->getTargetOpts().Features = TargetFeatures;
1355  Clang->setTarget(TargetInfo::CreateTargetInfo(Clang->getDiagnostics(),
1356                                               Clang->getTargetOpts()));
1357  if (!Clang->hasTarget()) {
1358    llvm::sys::Path(FrontendOpts.OutputFile).eraseFromDisk();
1359    Preamble.clear();
1360    PreambleRebuildCounter = DefaultPreambleRebuildInterval;
1361    PreprocessorOpts.eraseRemappedFile(
1362                               PreprocessorOpts.remapped_file_buffer_end() - 1);
1363    return 0;
1364  }
1365
1366  // Inform the target of the language options.
1367  //
1368  // FIXME: We shouldn't need to do this, the target should be immutable once
1369  // created. This complexity should be lifted elsewhere.
1370  Clang->getTarget().setForcedLangOptions(Clang->getLangOpts());
1371
1372  assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
1373         "Invocation must have exactly one source file!");
1374  assert(Clang->getFrontendOpts().Inputs[0].first != IK_AST &&
1375         "FIXME: AST inputs not yet supported here!");
1376  assert(Clang->getFrontendOpts().Inputs[0].first != IK_LLVM_IR &&
1377         "IR inputs not support here!");
1378
1379  // Clear out old caches and data.
1380  getDiagnostics().Reset();
1381  ProcessWarningOptions(getDiagnostics(), Clang->getDiagnosticOpts());
1382  StoredDiagnostics.erase(
1383                    StoredDiagnostics.begin() + NumStoredDiagnosticsFromDriver,
1384                          StoredDiagnostics.end());
1385  TopLevelDecls.clear();
1386  TopLevelDeclsInPreamble.clear();
1387  PreprocessedEntities.clear();
1388  PreprocessedEntitiesInPreamble.clear();
1389
1390  // Create a file manager object to provide access to and cache the filesystem.
1391  Clang->setFileManager(new FileManager(Clang->getFileSystemOpts()));
1392
1393  // Create the source manager.
1394  Clang->setSourceManager(new SourceManager(getDiagnostics(),
1395                                           Clang->getFileManager()));
1396
1397  llvm::OwningPtr<PrecompilePreambleAction> Act;
1398  Act.reset(new PrecompilePreambleAction(*this));
1399  if (!Act->BeginSourceFile(*Clang.get(), Clang->getFrontendOpts().Inputs[0].second,
1400                            Clang->getFrontendOpts().Inputs[0].first)) {
1401    Clang->takeInvocation();
1402    llvm::sys::Path(FrontendOpts.OutputFile).eraseFromDisk();
1403    Preamble.clear();
1404    PreambleRebuildCounter = DefaultPreambleRebuildInterval;
1405    PreprocessorOpts.eraseRemappedFile(
1406                               PreprocessorOpts.remapped_file_buffer_end() - 1);
1407    return 0;
1408  }
1409
1410  Act->Execute();
1411  Act->EndSourceFile();
1412  Clang->takeInvocation();
1413
1414  if (Diagnostics->hasErrorOccurred()) {
1415    // There were errors parsing the preamble, so no precompiled header was
1416    // generated. Forget that we even tried.
1417    // FIXME: Should we leave a note for ourselves to try again?
1418    llvm::sys::Path(FrontendOpts.OutputFile).eraseFromDisk();
1419    Preamble.clear();
1420    TopLevelDeclsInPreamble.clear();
1421    PreprocessedEntities.clear();
1422    PreprocessedEntitiesInPreamble.clear();
1423    PreambleRebuildCounter = DefaultPreambleRebuildInterval;
1424    PreprocessorOpts.eraseRemappedFile(
1425                               PreprocessorOpts.remapped_file_buffer_end() - 1);
1426    return 0;
1427  }
1428
1429  // Keep track of the preamble we precompiled.
1430  PreambleFile = FrontendOpts.OutputFile;
1431  NumStoredDiagnosticsInPreamble = StoredDiagnostics.size();
1432  NumWarningsInPreamble = getDiagnostics().getNumWarnings();
1433
1434  // Keep track of all of the files that the source manager knows about,
1435  // so we can verify whether they have changed or not.
1436  FilesInPreamble.clear();
1437  SourceManager &SourceMgr = Clang->getSourceManager();
1438  const llvm::MemoryBuffer *MainFileBuffer
1439    = SourceMgr.getBuffer(SourceMgr.getMainFileID());
1440  for (SourceManager::fileinfo_iterator F = SourceMgr.fileinfo_begin(),
1441                                     FEnd = SourceMgr.fileinfo_end();
1442       F != FEnd;
1443       ++F) {
1444    const FileEntry *File = F->second->OrigEntry;
1445    if (!File || F->second->getRawBuffer() == MainFileBuffer)
1446      continue;
1447
1448    FilesInPreamble[File->getName()]
1449      = std::make_pair(F->second->getSize(), File->getModificationTime());
1450  }
1451
1452  PreambleRebuildCounter = 1;
1453  PreprocessorOpts.eraseRemappedFile(
1454                               PreprocessorOpts.remapped_file_buffer_end() - 1);
1455
1456  // If the hash of top-level entities differs from the hash of the top-level
1457  // entities the last time we rebuilt the preamble, clear out the completion
1458  // cache.
1459  if (CurrentTopLevelHashValue != PreambleTopLevelHashValue) {
1460    CompletionCacheTopLevelHashValue = 0;
1461    PreambleTopLevelHashValue = CurrentTopLevelHashValue;
1462  }
1463
1464  return CreatePaddedMainFileBuffer(NewPreamble.first,
1465                                    PreambleReservedSize,
1466                                    FrontendOpts.Inputs[0].second);
1467}
1468
1469void ASTUnit::RealizeTopLevelDeclsFromPreamble() {
1470  std::vector<Decl *> Resolved;
1471  Resolved.reserve(TopLevelDeclsInPreamble.size());
1472  ExternalASTSource &Source = *getASTContext().getExternalSource();
1473  for (unsigned I = 0, N = TopLevelDeclsInPreamble.size(); I != N; ++I) {
1474    // Resolve the declaration ID to an actual declaration, possibly
1475    // deserializing the declaration in the process.
1476    Decl *D = Source.GetExternalDecl(TopLevelDeclsInPreamble[I]);
1477    if (D)
1478      Resolved.push_back(D);
1479  }
1480  TopLevelDeclsInPreamble.clear();
1481  TopLevelDecls.insert(TopLevelDecls.begin(), Resolved.begin(), Resolved.end());
1482}
1483
1484void ASTUnit::RealizePreprocessedEntitiesFromPreamble() {
1485  if (!PP)
1486    return;
1487
1488  PreprocessingRecord *PPRec = PP->getPreprocessingRecord();
1489  if (!PPRec)
1490    return;
1491
1492  ExternalPreprocessingRecordSource *External = PPRec->getExternalSource();
1493  if (!External)
1494    return;
1495
1496  for (unsigned I = 0, N = PreprocessedEntitiesInPreamble.size(); I != N; ++I) {
1497    if (PreprocessedEntity *PE
1498          = External->ReadPreprocessedEntityAtOffset(
1499                                            PreprocessedEntitiesInPreamble[I]))
1500      PreprocessedEntities.push_back(PE);
1501  }
1502
1503  if (PreprocessedEntities.empty())
1504    return;
1505
1506  PreprocessedEntities.insert(PreprocessedEntities.end(),
1507                              PPRec->begin(true), PPRec->end(true));
1508}
1509
1510ASTUnit::pp_entity_iterator ASTUnit::pp_entity_begin() {
1511  if (!PreprocessedEntitiesInPreamble.empty() &&
1512      PreprocessedEntities.empty())
1513    RealizePreprocessedEntitiesFromPreamble();
1514
1515  if (PreprocessedEntities.empty())
1516    if (PreprocessingRecord *PPRec = PP->getPreprocessingRecord())
1517      return PPRec->begin(true);
1518
1519  return PreprocessedEntities.begin();
1520}
1521
1522ASTUnit::pp_entity_iterator ASTUnit::pp_entity_end() {
1523  if (!PreprocessedEntitiesInPreamble.empty() &&
1524      PreprocessedEntities.empty())
1525    RealizePreprocessedEntitiesFromPreamble();
1526
1527  if (PreprocessedEntities.empty())
1528    if (PreprocessingRecord *PPRec = PP->getPreprocessingRecord())
1529      return PPRec->end(true);
1530
1531  return PreprocessedEntities.end();
1532}
1533
1534unsigned ASTUnit::getMaxPCHLevel() const {
1535  if (!getOnlyLocalDecls())
1536    return Decl::MaxPCHLevel;
1537
1538  return 0;
1539}
1540
1541llvm::StringRef ASTUnit::getMainFileName() const {
1542  return Invocation->getFrontendOpts().Inputs[0].second;
1543}
1544
1545ASTUnit *ASTUnit::create(CompilerInvocation *CI,
1546                         llvm::IntrusiveRefCntPtr<Diagnostic> Diags) {
1547  llvm::OwningPtr<ASTUnit> AST;
1548  AST.reset(new ASTUnit(false));
1549  ConfigureDiags(Diags, 0, 0, *AST, /*CaptureDiagnostics=*/false);
1550  AST->Diagnostics = Diags;
1551  AST->Invocation.reset(CI);
1552  AST->FileSystemOpts = CI->getFileSystemOpts();
1553  AST->FileMgr.reset(new FileManager(AST->FileSystemOpts));
1554  AST->SourceMgr.reset(new SourceManager(*Diags, *AST->FileMgr));
1555
1556  return AST.take();
1557}
1558
1559bool ASTUnit::LoadFromCompilerInvocation(bool PrecompilePreamble) {
1560  if (!Invocation)
1561    return true;
1562
1563  // We'll manage file buffers ourselves.
1564  Invocation->getPreprocessorOpts().RetainRemappedFileBuffers = true;
1565  Invocation->getFrontendOpts().DisableFree = false;
1566  ProcessWarningOptions(getDiagnostics(), Invocation->getDiagnosticOpts());
1567
1568  // Save the target features.
1569  TargetFeatures = Invocation->getTargetOpts().Features;
1570
1571  llvm::MemoryBuffer *OverrideMainBuffer = 0;
1572  if (PrecompilePreamble) {
1573    PreambleRebuildCounter = 2;
1574    OverrideMainBuffer
1575      = getMainBufferWithPrecompiledPreamble(*Invocation);
1576  }
1577
1578  SimpleTimer ParsingTimer(WantTiming);
1579  ParsingTimer.setOutput("Parsing " + getMainFileName());
1580
1581  return Parse(OverrideMainBuffer);
1582}
1583
1584ASTUnit *ASTUnit::LoadFromCompilerInvocation(CompilerInvocation *CI,
1585                                   llvm::IntrusiveRefCntPtr<Diagnostic> Diags,
1586                                             bool OnlyLocalDecls,
1587                                             bool CaptureDiagnostics,
1588                                             bool PrecompilePreamble,
1589                                             bool CompleteTranslationUnit,
1590                                             bool CacheCodeCompletionResults) {
1591  // Create the AST unit.
1592  llvm::OwningPtr<ASTUnit> AST;
1593  AST.reset(new ASTUnit(false));
1594  ConfigureDiags(Diags, 0, 0, *AST, CaptureDiagnostics);
1595  AST->Diagnostics = Diags;
1596  AST->OnlyLocalDecls = OnlyLocalDecls;
1597  AST->CaptureDiagnostics = CaptureDiagnostics;
1598  AST->CompleteTranslationUnit = CompleteTranslationUnit;
1599  AST->ShouldCacheCodeCompletionResults = CacheCodeCompletionResults;
1600  AST->Invocation.reset(CI);
1601
1602  // Recover resources if we crash before exiting this method.
1603  llvm::CrashRecoveryContextCleanupRegistrar
1604    ASTUnitCleanup(llvm::CrashRecoveryContextCleanup::
1605                   create<ASTUnit>(AST.get()));
1606
1607  return AST->LoadFromCompilerInvocation(PrecompilePreamble)? 0 : AST.take();
1608}
1609
1610ASTUnit *ASTUnit::LoadFromCommandLine(const char **ArgBegin,
1611                                      const char **ArgEnd,
1612                                    llvm::IntrusiveRefCntPtr<Diagnostic> Diags,
1613                                      llvm::StringRef ResourceFilesPath,
1614                                      bool OnlyLocalDecls,
1615                                      bool CaptureDiagnostics,
1616                                      RemappedFile *RemappedFiles,
1617                                      unsigned NumRemappedFiles,
1618                                      bool RemappedFilesKeepOriginalName,
1619                                      bool PrecompilePreamble,
1620                                      bool CompleteTranslationUnit,
1621                                      bool CacheCodeCompletionResults,
1622                                      bool CXXPrecompilePreamble,
1623                                      bool CXXChainedPCH) {
1624  if (!Diags.getPtr()) {
1625    // No diagnostics engine was provided, so create our own diagnostics object
1626    // with the default options.
1627    DiagnosticOptions DiagOpts;
1628    Diags = CompilerInstance::createDiagnostics(DiagOpts, ArgEnd - ArgBegin,
1629                                                ArgBegin);
1630  }
1631
1632  llvm::SmallVector<const char *, 16> Args;
1633  Args.push_back("<clang>"); // FIXME: Remove dummy argument.
1634  Args.insert(Args.end(), ArgBegin, ArgEnd);
1635
1636  // FIXME: Find a cleaner way to force the driver into restricted modes. We
1637  // also want to force it to use clang.
1638  Args.push_back("-fsyntax-only");
1639
1640  llvm::SmallVector<StoredDiagnostic, 4> StoredDiagnostics;
1641
1642  llvm::OwningPtr<CompilerInvocation> CI;
1643
1644  {
1645    CaptureDroppedDiagnostics Capture(CaptureDiagnostics, *Diags,
1646                                      StoredDiagnostics);
1647
1648    // FIXME: We shouldn't have to pass in the path info.
1649    driver::Driver TheDriver("clang", llvm::sys::getHostTriple(),
1650                             "a.out", false, false, *Diags);
1651
1652    // Don't check that inputs exist, they have been remapped.
1653    TheDriver.setCheckInputsExist(false);
1654
1655    llvm::OwningPtr<driver::Compilation> C(
1656      TheDriver.BuildCompilation(Args.size(), Args.data()));
1657
1658    // Just print the cc1 options if -### was present.
1659    if (C->getArgs().hasArg(driver::options::OPT__HASH_HASH_HASH)) {
1660      C->PrintJob(llvm::errs(), C->getJobs(), "\n", true);
1661      return 0;
1662    }
1663
1664    // We expect to get back exactly one command job, if we didn't something
1665    // failed.
1666    const driver::JobList &Jobs = C->getJobs();
1667    if (Jobs.size() != 1 || !isa<driver::Command>(Jobs.begin())) {
1668      llvm::SmallString<256> Msg;
1669      llvm::raw_svector_ostream OS(Msg);
1670      C->PrintJob(OS, C->getJobs(), "; ", true);
1671      Diags->Report(diag::err_fe_expected_compiler_job) << OS.str();
1672      return 0;
1673    }
1674
1675    const driver::Command *Cmd = cast<driver::Command>(*Jobs.begin());
1676    if (llvm::StringRef(Cmd->getCreator().getName()) != "clang") {
1677      Diags->Report(diag::err_fe_expected_clang_command);
1678      return 0;
1679    }
1680
1681    const driver::ArgStringList &CCArgs = Cmd->getArguments();
1682    CI.reset(new CompilerInvocation);
1683    CompilerInvocation::CreateFromArgs(*CI,
1684                                     const_cast<const char **>(CCArgs.data()),
1685                                     const_cast<const char **>(CCArgs.data()) +
1686                                       CCArgs.size(),
1687                                       *Diags);
1688  }
1689
1690  // Override any files that need remapping
1691  for (unsigned I = 0; I != NumRemappedFiles; ++I) {
1692    FilenameOrMemBuf fileOrBuf = RemappedFiles[I].second;
1693    if (const llvm::MemoryBuffer *
1694            memBuf = fileOrBuf.dyn_cast<const llvm::MemoryBuffer *>()) {
1695      CI->getPreprocessorOpts().addRemappedFile(RemappedFiles[I].first, memBuf);
1696    } else {
1697      const char *fname = fileOrBuf.get<const char *>();
1698      CI->getPreprocessorOpts().addRemappedFile(RemappedFiles[I].first, fname);
1699    }
1700  }
1701  CI->getPreprocessorOpts().RemappedFilesKeepOriginalName =
1702                                                  RemappedFilesKeepOriginalName;
1703
1704  // Override the resources path.
1705  CI->getHeaderSearchOpts().ResourceDir = ResourceFilesPath;
1706
1707  // Check whether we should precompile the preamble and/or use chained PCH.
1708  // FIXME: This is a temporary hack while we debug C++ chained PCH.
1709  if (CI->getLangOpts().CPlusPlus) {
1710    PrecompilePreamble = PrecompilePreamble && CXXPrecompilePreamble;
1711
1712    if (PrecompilePreamble && !CXXChainedPCH &&
1713        !CI->getPreprocessorOpts().ImplicitPCHInclude.empty())
1714      PrecompilePreamble = false;
1715  }
1716
1717  // Create the AST unit.
1718  llvm::OwningPtr<ASTUnit> AST;
1719  AST.reset(new ASTUnit(false));
1720  ConfigureDiags(Diags, ArgBegin, ArgEnd, *AST, CaptureDiagnostics);
1721  AST->Diagnostics = Diags;
1722
1723  AST->FileSystemOpts = CI->getFileSystemOpts();
1724  AST->FileMgr.reset(new FileManager(AST->FileSystemOpts));
1725  AST->OnlyLocalDecls = OnlyLocalDecls;
1726  AST->CaptureDiagnostics = CaptureDiagnostics;
1727  AST->CompleteTranslationUnit = CompleteTranslationUnit;
1728  AST->ShouldCacheCodeCompletionResults = CacheCodeCompletionResults;
1729  AST->NumStoredDiagnosticsFromDriver = StoredDiagnostics.size();
1730  AST->NumStoredDiagnosticsInPreamble = StoredDiagnostics.size();
1731  AST->StoredDiagnostics.swap(StoredDiagnostics);
1732  AST->Invocation.reset(CI.take());
1733
1734  // Recover resources if we crash before exiting this method.
1735  llvm::CrashRecoveryContextCleanupRegistrar
1736    ASTUnitCleanup(llvm::CrashRecoveryContextCleanup::
1737                    create<ASTUnit>(AST.get()));
1738
1739  return AST->LoadFromCompilerInvocation(PrecompilePreamble) ? 0 : AST.take();
1740}
1741
1742bool ASTUnit::Reparse(RemappedFile *RemappedFiles, unsigned NumRemappedFiles) {
1743  if (!Invocation.get())
1744    return true;
1745
1746  SimpleTimer ParsingTimer(WantTiming);
1747  ParsingTimer.setOutput("Reparsing " + getMainFileName());
1748
1749  // Remap files.
1750  PreprocessorOptions &PPOpts = Invocation->getPreprocessorOpts();
1751  PPOpts.DisableStatCache = true;
1752  for (PreprocessorOptions::remapped_file_buffer_iterator
1753         R = PPOpts.remapped_file_buffer_begin(),
1754         REnd = PPOpts.remapped_file_buffer_end();
1755       R != REnd;
1756       ++R) {
1757    delete R->second;
1758  }
1759  Invocation->getPreprocessorOpts().clearRemappedFiles();
1760  for (unsigned I = 0; I != NumRemappedFiles; ++I) {
1761    FilenameOrMemBuf fileOrBuf = RemappedFiles[I].second;
1762    if (const llvm::MemoryBuffer *
1763            memBuf = fileOrBuf.dyn_cast<const llvm::MemoryBuffer *>()) {
1764      Invocation->getPreprocessorOpts().addRemappedFile(RemappedFiles[I].first,
1765                                                        memBuf);
1766    } else {
1767      const char *fname = fileOrBuf.get<const char *>();
1768      Invocation->getPreprocessorOpts().addRemappedFile(RemappedFiles[I].first,
1769                                                        fname);
1770    }
1771  }
1772
1773  // If we have a preamble file lying around, or if we might try to
1774  // build a precompiled preamble, do so now.
1775  llvm::MemoryBuffer *OverrideMainBuffer = 0;
1776  if (!PreambleFile.empty() || PreambleRebuildCounter > 0)
1777    OverrideMainBuffer = getMainBufferWithPrecompiledPreamble(*Invocation);
1778
1779  // Clear out the diagnostics state.
1780  if (!OverrideMainBuffer) {
1781    getDiagnostics().Reset();
1782    ProcessWarningOptions(getDiagnostics(), Invocation->getDiagnosticOpts());
1783  }
1784
1785  // Parse the sources
1786  bool Result = Parse(OverrideMainBuffer);
1787
1788  // If we're caching global code-completion results, and the top-level
1789  // declarations have changed, clear out the code-completion cache.
1790  if (!Result && ShouldCacheCodeCompletionResults &&
1791      CurrentTopLevelHashValue != CompletionCacheTopLevelHashValue)
1792    CacheCodeCompletionResults();
1793
1794  return Result;
1795}
1796
1797//----------------------------------------------------------------------------//
1798// Code completion
1799//----------------------------------------------------------------------------//
1800
1801namespace {
1802  /// \brief Code completion consumer that combines the cached code-completion
1803  /// results from an ASTUnit with the code-completion results provided to it,
1804  /// then passes the result on to
1805  class AugmentedCodeCompleteConsumer : public CodeCompleteConsumer {
1806    unsigned NormalContexts;
1807    ASTUnit &AST;
1808    CodeCompleteConsumer &Next;
1809
1810  public:
1811    AugmentedCodeCompleteConsumer(ASTUnit &AST, CodeCompleteConsumer &Next,
1812                                  bool IncludeMacros, bool IncludeCodePatterns,
1813                                  bool IncludeGlobals)
1814      : CodeCompleteConsumer(IncludeMacros, IncludeCodePatterns, IncludeGlobals,
1815                             Next.isOutputBinary()), AST(AST), Next(Next)
1816    {
1817      // Compute the set of contexts in which we will look when we don't have
1818      // any information about the specific context.
1819      NormalContexts
1820        = (1 << (CodeCompletionContext::CCC_TopLevel - 1))
1821        | (1 << (CodeCompletionContext::CCC_ObjCInterface - 1))
1822        | (1 << (CodeCompletionContext::CCC_ObjCImplementation - 1))
1823        | (1 << (CodeCompletionContext::CCC_ObjCIvarList - 1))
1824        | (1 << (CodeCompletionContext::CCC_Statement - 1))
1825        | (1 << (CodeCompletionContext::CCC_Expression - 1))
1826        | (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1))
1827        | (1 << (CodeCompletionContext::CCC_MemberAccess - 1))
1828        | (1 << (CodeCompletionContext::CCC_ObjCProtocolName - 1))
1829        | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1))
1830        | (1 << (CodeCompletionContext::CCC_Recovery - 1));
1831
1832      if (AST.getASTContext().getLangOptions().CPlusPlus)
1833        NormalContexts |= (1 << (CodeCompletionContext::CCC_EnumTag - 1))
1834                    | (1 << (CodeCompletionContext::CCC_UnionTag - 1))
1835                    | (1 << (CodeCompletionContext::CCC_ClassOrStructTag - 1));
1836    }
1837
1838    virtual void ProcessCodeCompleteResults(Sema &S,
1839                                            CodeCompletionContext Context,
1840                                            CodeCompletionResult *Results,
1841                                            unsigned NumResults);
1842
1843    virtual void ProcessOverloadCandidates(Sema &S, unsigned CurrentArg,
1844                                           OverloadCandidate *Candidates,
1845                                           unsigned NumCandidates) {
1846      Next.ProcessOverloadCandidates(S, CurrentArg, Candidates, NumCandidates);
1847    }
1848
1849    virtual CodeCompletionAllocator &getAllocator() {
1850      return Next.getAllocator();
1851    }
1852  };
1853}
1854
1855/// \brief Helper function that computes which global names are hidden by the
1856/// local code-completion results.
1857static void CalculateHiddenNames(const CodeCompletionContext &Context,
1858                                 CodeCompletionResult *Results,
1859                                 unsigned NumResults,
1860                                 ASTContext &Ctx,
1861                          llvm::StringSet<llvm::BumpPtrAllocator> &HiddenNames){
1862  bool OnlyTagNames = false;
1863  switch (Context.getKind()) {
1864  case CodeCompletionContext::CCC_Recovery:
1865  case CodeCompletionContext::CCC_TopLevel:
1866  case CodeCompletionContext::CCC_ObjCInterface:
1867  case CodeCompletionContext::CCC_ObjCImplementation:
1868  case CodeCompletionContext::CCC_ObjCIvarList:
1869  case CodeCompletionContext::CCC_ClassStructUnion:
1870  case CodeCompletionContext::CCC_Statement:
1871  case CodeCompletionContext::CCC_Expression:
1872  case CodeCompletionContext::CCC_ObjCMessageReceiver:
1873  case CodeCompletionContext::CCC_MemberAccess:
1874  case CodeCompletionContext::CCC_Namespace:
1875  case CodeCompletionContext::CCC_Type:
1876  case CodeCompletionContext::CCC_Name:
1877  case CodeCompletionContext::CCC_PotentiallyQualifiedName:
1878  case CodeCompletionContext::CCC_ParenthesizedExpression:
1879    break;
1880
1881  case CodeCompletionContext::CCC_EnumTag:
1882  case CodeCompletionContext::CCC_UnionTag:
1883  case CodeCompletionContext::CCC_ClassOrStructTag:
1884    OnlyTagNames = true;
1885    break;
1886
1887  case CodeCompletionContext::CCC_ObjCProtocolName:
1888  case CodeCompletionContext::CCC_MacroName:
1889  case CodeCompletionContext::CCC_MacroNameUse:
1890  case CodeCompletionContext::CCC_PreprocessorExpression:
1891  case CodeCompletionContext::CCC_PreprocessorDirective:
1892  case CodeCompletionContext::CCC_NaturalLanguage:
1893  case CodeCompletionContext::CCC_SelectorName:
1894  case CodeCompletionContext::CCC_TypeQualifiers:
1895  case CodeCompletionContext::CCC_Other:
1896  case CodeCompletionContext::CCC_OtherWithMacros:
1897    // We're looking for nothing, or we're looking for names that cannot
1898    // be hidden.
1899    return;
1900  }
1901
1902  typedef CodeCompletionResult Result;
1903  for (unsigned I = 0; I != NumResults; ++I) {
1904    if (Results[I].Kind != Result::RK_Declaration)
1905      continue;
1906
1907    unsigned IDNS
1908      = Results[I].Declaration->getUnderlyingDecl()->getIdentifierNamespace();
1909
1910    bool Hiding = false;
1911    if (OnlyTagNames)
1912      Hiding = (IDNS & Decl::IDNS_Tag);
1913    else {
1914      unsigned HiddenIDNS = (Decl::IDNS_Type | Decl::IDNS_Member |
1915                             Decl::IDNS_Namespace | Decl::IDNS_Ordinary |
1916                             Decl::IDNS_NonMemberOperator);
1917      if (Ctx.getLangOptions().CPlusPlus)
1918        HiddenIDNS |= Decl::IDNS_Tag;
1919      Hiding = (IDNS & HiddenIDNS);
1920    }
1921
1922    if (!Hiding)
1923      continue;
1924
1925    DeclarationName Name = Results[I].Declaration->getDeclName();
1926    if (IdentifierInfo *Identifier = Name.getAsIdentifierInfo())
1927      HiddenNames.insert(Identifier->getName());
1928    else
1929      HiddenNames.insert(Name.getAsString());
1930  }
1931}
1932
1933
1934void AugmentedCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &S,
1935                                            CodeCompletionContext Context,
1936                                            CodeCompletionResult *Results,
1937                                            unsigned NumResults) {
1938  // Merge the results we were given with the results we cached.
1939  bool AddedResult = false;
1940  unsigned InContexts
1941    = (Context.getKind() == CodeCompletionContext::CCC_Recovery? NormalContexts
1942                                            : (1 << (Context.getKind() - 1)));
1943
1944  // Contains the set of names that are hidden by "local" completion results.
1945  llvm::StringSet<llvm::BumpPtrAllocator> HiddenNames;
1946  typedef CodeCompletionResult Result;
1947  llvm::SmallVector<Result, 8> AllResults;
1948  for (ASTUnit::cached_completion_iterator
1949            C = AST.cached_completion_begin(),
1950         CEnd = AST.cached_completion_end();
1951       C != CEnd; ++C) {
1952    // If the context we are in matches any of the contexts we are
1953    // interested in, we'll add this result.
1954    if ((C->ShowInContexts & InContexts) == 0)
1955      continue;
1956
1957    // If we haven't added any results previously, do so now.
1958    if (!AddedResult) {
1959      CalculateHiddenNames(Context, Results, NumResults, S.Context,
1960                           HiddenNames);
1961      AllResults.insert(AllResults.end(), Results, Results + NumResults);
1962      AddedResult = true;
1963    }
1964
1965    // Determine whether this global completion result is hidden by a local
1966    // completion result. If so, skip it.
1967    if (C->Kind != CXCursor_MacroDefinition &&
1968        HiddenNames.count(C->Completion->getTypedText()))
1969      continue;
1970
1971    // Adjust priority based on similar type classes.
1972    unsigned Priority = C->Priority;
1973    CXCursorKind CursorKind = C->Kind;
1974    CodeCompletionString *Completion = C->Completion;
1975    if (!Context.getPreferredType().isNull()) {
1976      if (C->Kind == CXCursor_MacroDefinition) {
1977        Priority = getMacroUsagePriority(C->Completion->getTypedText(),
1978                                         S.getLangOptions(),
1979                               Context.getPreferredType()->isAnyPointerType());
1980      } else if (C->Type) {
1981        CanQualType Expected
1982          = S.Context.getCanonicalType(
1983                               Context.getPreferredType().getUnqualifiedType());
1984        SimplifiedTypeClass ExpectedSTC = getSimplifiedTypeClass(Expected);
1985        if (ExpectedSTC == C->TypeClass) {
1986          // We know this type is similar; check for an exact match.
1987          llvm::StringMap<unsigned> &CachedCompletionTypes
1988            = AST.getCachedCompletionTypes();
1989          llvm::StringMap<unsigned>::iterator Pos
1990            = CachedCompletionTypes.find(QualType(Expected).getAsString());
1991          if (Pos != CachedCompletionTypes.end() && Pos->second == C->Type)
1992            Priority /= CCF_ExactTypeMatch;
1993          else
1994            Priority /= CCF_SimilarTypeMatch;
1995        }
1996      }
1997    }
1998
1999    // Adjust the completion string, if required.
2000    if (C->Kind == CXCursor_MacroDefinition &&
2001        Context.getKind() == CodeCompletionContext::CCC_MacroNameUse) {
2002      // Create a new code-completion string that just contains the
2003      // macro name, without its arguments.
2004      CodeCompletionBuilder Builder(getAllocator(), CCP_CodePattern,
2005                                    C->Availability);
2006      Builder.AddTypedTextChunk(C->Completion->getTypedText());
2007      CursorKind = CXCursor_NotImplemented;
2008      Priority = CCP_CodePattern;
2009      Completion = Builder.TakeString();
2010    }
2011
2012    AllResults.push_back(Result(Completion, Priority, CursorKind,
2013                                C->Availability));
2014  }
2015
2016  // If we did not add any cached completion results, just forward the
2017  // results we were given to the next consumer.
2018  if (!AddedResult) {
2019    Next.ProcessCodeCompleteResults(S, Context, Results, NumResults);
2020    return;
2021  }
2022
2023  Next.ProcessCodeCompleteResults(S, Context, AllResults.data(),
2024                                  AllResults.size());
2025}
2026
2027
2028
2029void ASTUnit::CodeComplete(llvm::StringRef File, unsigned Line, unsigned Column,
2030                           RemappedFile *RemappedFiles,
2031                           unsigned NumRemappedFiles,
2032                           bool IncludeMacros,
2033                           bool IncludeCodePatterns,
2034                           CodeCompleteConsumer &Consumer,
2035                           Diagnostic &Diag, LangOptions &LangOpts,
2036                           SourceManager &SourceMgr, FileManager &FileMgr,
2037                   llvm::SmallVectorImpl<StoredDiagnostic> &StoredDiagnostics,
2038             llvm::SmallVectorImpl<const llvm::MemoryBuffer *> &OwnedBuffers) {
2039  if (!Invocation.get())
2040    return;
2041
2042  SimpleTimer CompletionTimer(WantTiming);
2043  CompletionTimer.setOutput("Code completion @ " + File + ":" +
2044                            llvm::Twine(Line) + ":" + llvm::Twine(Column));
2045
2046  CompilerInvocation CCInvocation(*Invocation);
2047  FrontendOptions &FrontendOpts = CCInvocation.getFrontendOpts();
2048  PreprocessorOptions &PreprocessorOpts = CCInvocation.getPreprocessorOpts();
2049
2050  FrontendOpts.ShowMacrosInCodeCompletion
2051    = IncludeMacros && CachedCompletionResults.empty();
2052  FrontendOpts.ShowCodePatternsInCodeCompletion = IncludeCodePatterns;
2053  FrontendOpts.ShowGlobalSymbolsInCodeCompletion
2054    = CachedCompletionResults.empty();
2055  FrontendOpts.CodeCompletionAt.FileName = File;
2056  FrontendOpts.CodeCompletionAt.Line = Line;
2057  FrontendOpts.CodeCompletionAt.Column = Column;
2058
2059  // Set the language options appropriately.
2060  LangOpts = CCInvocation.getLangOpts();
2061
2062  llvm::OwningPtr<CompilerInstance> Clang(new CompilerInstance());
2063
2064  // Recover resources if we crash before exiting this method.
2065  llvm::CrashRecoveryContextCleanupRegistrar
2066    CICleanup(llvm::CrashRecoveryContextCleanup::
2067                    create<CompilerInstance>(Clang.get()));
2068
2069  Clang->setInvocation(&CCInvocation);
2070  OriginalSourceFile = Clang->getFrontendOpts().Inputs[0].second;
2071
2072  // Set up diagnostics, capturing any diagnostics produced.
2073  Clang->setDiagnostics(&Diag);
2074  ProcessWarningOptions(Diag, CCInvocation.getDiagnosticOpts());
2075  CaptureDroppedDiagnostics Capture(true,
2076                                    Clang->getDiagnostics(),
2077                                    StoredDiagnostics);
2078
2079  // Create the target instance.
2080  Clang->getTargetOpts().Features = TargetFeatures;
2081  Clang->setTarget(TargetInfo::CreateTargetInfo(Clang->getDiagnostics(),
2082                                               Clang->getTargetOpts()));
2083  if (!Clang->hasTarget()) {
2084    Clang->takeInvocation();
2085    return;
2086  }
2087
2088  // Inform the target of the language options.
2089  //
2090  // FIXME: We shouldn't need to do this, the target should be immutable once
2091  // created. This complexity should be lifted elsewhere.
2092  Clang->getTarget().setForcedLangOptions(Clang->getLangOpts());
2093
2094  assert(Clang->getFrontendOpts().Inputs.size() == 1 &&
2095         "Invocation must have exactly one source file!");
2096  assert(Clang->getFrontendOpts().Inputs[0].first != IK_AST &&
2097         "FIXME: AST inputs not yet supported here!");
2098  assert(Clang->getFrontendOpts().Inputs[0].first != IK_LLVM_IR &&
2099         "IR inputs not support here!");
2100
2101
2102  // Use the source and file managers that we were given.
2103  Clang->setFileManager(&FileMgr);
2104  Clang->setSourceManager(&SourceMgr);
2105
2106  // Remap files.
2107  PreprocessorOpts.clearRemappedFiles();
2108  PreprocessorOpts.RetainRemappedFileBuffers = true;
2109  for (unsigned I = 0; I != NumRemappedFiles; ++I) {
2110    FilenameOrMemBuf fileOrBuf = RemappedFiles[I].second;
2111    if (const llvm::MemoryBuffer *
2112            memBuf = fileOrBuf.dyn_cast<const llvm::MemoryBuffer *>()) {
2113      PreprocessorOpts.addRemappedFile(RemappedFiles[I].first, memBuf);
2114      OwnedBuffers.push_back(memBuf);
2115    } else {
2116      const char *fname = fileOrBuf.get<const char *>();
2117      PreprocessorOpts.addRemappedFile(RemappedFiles[I].first, fname);
2118    }
2119  }
2120
2121  // Use the code completion consumer we were given, but adding any cached
2122  // code-completion results.
2123  AugmentedCodeCompleteConsumer *AugmentedConsumer
2124    = new AugmentedCodeCompleteConsumer(*this, Consumer,
2125                                        FrontendOpts.ShowMacrosInCodeCompletion,
2126                                FrontendOpts.ShowCodePatternsInCodeCompletion,
2127                                FrontendOpts.ShowGlobalSymbolsInCodeCompletion);
2128  Clang->setCodeCompletionConsumer(AugmentedConsumer);
2129
2130  // If we have a precompiled preamble, try to use it. We only allow
2131  // the use of the precompiled preamble if we're if the completion
2132  // point is within the main file, after the end of the precompiled
2133  // preamble.
2134  llvm::MemoryBuffer *OverrideMainBuffer = 0;
2135  if (!PreambleFile.empty()) {
2136    using llvm::sys::FileStatus;
2137    llvm::sys::PathWithStatus CompleteFilePath(File);
2138    llvm::sys::PathWithStatus MainPath(OriginalSourceFile);
2139    if (const FileStatus *CompleteFileStatus = CompleteFilePath.getFileStatus())
2140      if (const FileStatus *MainStatus = MainPath.getFileStatus())
2141        if (CompleteFileStatus->getUniqueID() == MainStatus->getUniqueID())
2142          OverrideMainBuffer
2143            = getMainBufferWithPrecompiledPreamble(CCInvocation, false,
2144                                                   Line - 1);
2145  }
2146
2147  // If the main file has been overridden due to the use of a preamble,
2148  // make that override happen and introduce the preamble.
2149  PreprocessorOpts.DisableStatCache = true;
2150  StoredDiagnostics.insert(StoredDiagnostics.end(),
2151                           this->StoredDiagnostics.begin(),
2152             this->StoredDiagnostics.begin() + NumStoredDiagnosticsFromDriver);
2153  if (OverrideMainBuffer) {
2154    PreprocessorOpts.addRemappedFile(OriginalSourceFile, OverrideMainBuffer);
2155    PreprocessorOpts.PrecompiledPreambleBytes.first = Preamble.size();
2156    PreprocessorOpts.PrecompiledPreambleBytes.second
2157                                                    = PreambleEndsAtStartOfLine;
2158    PreprocessorOpts.ImplicitPCHInclude = PreambleFile;
2159    PreprocessorOpts.DisablePCHValidation = true;
2160
2161    // The stored diagnostics have the old source manager. Copy them
2162    // to our output set of stored diagnostics, updating the source
2163    // manager to the one we were given.
2164    for (unsigned I = NumStoredDiagnosticsFromDriver,
2165                  N = this->StoredDiagnostics.size();
2166         I < N; ++I) {
2167      StoredDiagnostics.push_back(this->StoredDiagnostics[I]);
2168      FullSourceLoc Loc(StoredDiagnostics[I].getLocation(), SourceMgr);
2169      StoredDiagnostics[I].setLocation(Loc);
2170    }
2171
2172    OwnedBuffers.push_back(OverrideMainBuffer);
2173  } else {
2174    PreprocessorOpts.PrecompiledPreambleBytes.first = 0;
2175    PreprocessorOpts.PrecompiledPreambleBytes.second = false;
2176  }
2177
2178  llvm::OwningPtr<SyntaxOnlyAction> Act;
2179  Act.reset(new SyntaxOnlyAction);
2180  if (Act->BeginSourceFile(*Clang.get(), Clang->getFrontendOpts().Inputs[0].second,
2181                           Clang->getFrontendOpts().Inputs[0].first)) {
2182    Act->Execute();
2183    Act->EndSourceFile();
2184  }
2185
2186  // Steal back our resources.
2187  Clang->takeFileManager();
2188  Clang->takeSourceManager();
2189  Clang->takeInvocation();
2190}
2191
2192bool ASTUnit::Save(llvm::StringRef File) {
2193  if (getDiagnostics().hasErrorOccurred())
2194    return true;
2195
2196  // FIXME: Can we somehow regenerate the stat cache here, or do we need to
2197  // unconditionally create a stat cache when we parse the file?
2198  std::string ErrorInfo;
2199  llvm::raw_fd_ostream Out(File.str().c_str(), ErrorInfo,
2200                           llvm::raw_fd_ostream::F_Binary);
2201  if (!ErrorInfo.empty() || Out.has_error())
2202    return true;
2203
2204  serialize(Out);
2205  Out.close();
2206  return Out.has_error();
2207}
2208
2209bool ASTUnit::serialize(llvm::raw_ostream &OS) {
2210  if (getDiagnostics().hasErrorOccurred())
2211    return true;
2212
2213  std::vector<unsigned char> Buffer;
2214  llvm::BitstreamWriter Stream(Buffer);
2215  ASTWriter Writer(Stream);
2216  Writer.WriteAST(getSema(), 0, std::string(), 0);
2217
2218  // Write the generated bitstream to "Out".
2219  if (!Buffer.empty())
2220    OS.write((char *)&Buffer.front(), Buffer.size());
2221
2222  return false;
2223}
2224