ASTUnit.cpp revision 32be4a588fbb87d0d163ead49c42f5438bf0b2b7 
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/Tool.h"
24#include "clang/Frontend/CompilerInstance.h"
25#include "clang/Frontend/FrontendActions.h"
26#include "clang/Frontend/FrontendDiagnostic.h"
27#include "clang/Frontend/FrontendOptions.h"
28#include "clang/Frontend/Utils.h"
29#include "clang/Serialization/ASTReader.h"
30#include "clang/Serialization/ASTWriter.h"
31#include "clang/Lex/HeaderSearch.h"
32#include "clang/Lex/Preprocessor.h"
33#include "clang/Basic/TargetOptions.h"
34#include "clang/Basic/TargetInfo.h"
35#include "clang/Basic/Diagnostic.h"
36#include "llvm/ADT/StringSet.h"
37#include "llvm/Support/MemoryBuffer.h"
38#include "llvm/System/Host.h"
39#include "llvm/System/Path.h"
40#include "llvm/Support/raw_ostream.h"
41#include "llvm/Support/Timer.h"
42#include <cstdlib>
43#include <cstdio>
44#include <sys/stat.h>
45using namespace clang;
46
47/// \brief After failing to build a precompiled preamble (due to
48/// errors in the source that occurs in the preamble), the number of
49/// reparses during which we'll skip even trying to precompile the
50/// preamble.
51const unsigned DefaultPreambleRebuildInterval = 5;
52
53ASTUnit::ASTUnit(bool _MainFileIsAST)
54  : CaptureDiagnostics(false), MainFileIsAST(_MainFileIsAST),
55    CompleteTranslationUnit(true), ConcurrencyCheckValue(CheckUnlocked),
56    PreambleRebuildCounter(0), SavedMainFileBuffer(0), PreambleBuffer(0),
57    ShouldCacheCodeCompletionResults(false),
58    NumTopLevelDeclsAtLastCompletionCache(0),
59    CacheCodeCompletionCoolDown(0),
60    UnsafeToFree(false) {
61}
62
63ASTUnit::~ASTUnit() {
64  ConcurrencyCheckValue = CheckLocked;
65  CleanTemporaryFiles();
66  if (!PreambleFile.empty())
67    llvm::sys::Path(PreambleFile).eraseFromDisk();
68
69  // Free the buffers associated with remapped files. We are required to
70  // perform this operation here because we explicitly request that the
71  // compiler instance *not* free these buffers for each invocation of the
72  // parser.
73  if (Invocation.get()) {
74    PreprocessorOptions &PPOpts = Invocation->getPreprocessorOpts();
75    for (PreprocessorOptions::remapped_file_buffer_iterator
76           FB = PPOpts.remapped_file_buffer_begin(),
77           FBEnd = PPOpts.remapped_file_buffer_end();
78         FB != FBEnd;
79         ++FB)
80      delete FB->second;
81  }
82
83  delete SavedMainFileBuffer;
84  delete PreambleBuffer;
85
86  ClearCachedCompletionResults();
87
88  if (TimerGroup)
89    TimerGroup->printAll(llvm::errs());
90
91  for (unsigned I = 0, N = Timers.size(); I != N; ++I)
92    delete Timers[I];
93}
94
95void ASTUnit::CleanTemporaryFiles() {
96  for (unsigned I = 0, N = TemporaryFiles.size(); I != N; ++I)
97    TemporaryFiles[I].eraseFromDisk();
98  TemporaryFiles.clear();
99}
100
101/// \brief Determine the set of code-completion contexts in which this
102/// declaration should be shown.
103static unsigned getDeclShowContexts(NamedDecl *ND,
104                                    const LangOptions &LangOpts,
105                                    bool &IsNestedNameSpecifier) {
106  IsNestedNameSpecifier = false;
107
108  if (isa<UsingShadowDecl>(ND))
109    ND = dyn_cast<NamedDecl>(ND->getUnderlyingDecl());
110  if (!ND)
111    return 0;
112
113  unsigned Contexts = 0;
114  if (isa<TypeDecl>(ND) || isa<ObjCInterfaceDecl>(ND) ||
115      isa<ClassTemplateDecl>(ND) || isa<TemplateTemplateParmDecl>(ND)) {
116    // Types can appear in these contexts.
117    if (LangOpts.CPlusPlus || !isa<TagDecl>(ND))
118      Contexts |= (1 << (CodeCompletionContext::CCC_TopLevel - 1))
119                | (1 << (CodeCompletionContext::CCC_ObjCIvarList - 1))
120                | (1 << (CodeCompletionContext::CCC_ClassStructUnion - 1))
121                | (1 << (CodeCompletionContext::CCC_Statement - 1))
122                | (1 << (CodeCompletionContext::CCC_Type - 1))
123              | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1));
124
125    // In C++, types can appear in expressions contexts (for functional casts).
126    if (LangOpts.CPlusPlus)
127      Contexts |= (1 << (CodeCompletionContext::CCC_Expression - 1));
128
129    // In Objective-C, message sends can send interfaces. In Objective-C++,
130    // all types are available due to functional casts.
131    if (LangOpts.CPlusPlus || isa<ObjCInterfaceDecl>(ND))
132      Contexts |= (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1));
133
134    // Deal with tag names.
135    if (isa<EnumDecl>(ND)) {
136      Contexts |= (1 << (CodeCompletionContext::CCC_EnumTag - 1));
137
138      // Part of the nested-name-specifier in C++0x.
139      if (LangOpts.CPlusPlus0x)
140        IsNestedNameSpecifier = true;
141    } else if (RecordDecl *Record = dyn_cast<RecordDecl>(ND)) {
142      if (Record->isUnion())
143        Contexts |= (1 << (CodeCompletionContext::CCC_UnionTag - 1));
144      else
145        Contexts |= (1 << (CodeCompletionContext::CCC_ClassOrStructTag - 1));
146
147      if (LangOpts.CPlusPlus)
148        IsNestedNameSpecifier = true;
149    } else if (isa<ClassTemplateDecl>(ND))
150      IsNestedNameSpecifier = true;
151  } else if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND)) {
152    // Values can appear in these contexts.
153    Contexts = (1 << (CodeCompletionContext::CCC_Statement - 1))
154             | (1 << (CodeCompletionContext::CCC_Expression - 1))
155             | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1))
156             | (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1));
157  } else if (isa<ObjCProtocolDecl>(ND)) {
158    Contexts = (1 << (CodeCompletionContext::CCC_ObjCProtocolName - 1));
159  } else if (isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND)) {
160    Contexts = (1 << (CodeCompletionContext::CCC_Namespace - 1));
161
162    // Part of the nested-name-specifier.
163    IsNestedNameSpecifier = true;
164  }
165
166  return Contexts;
167}
168
169void ASTUnit::CacheCodeCompletionResults() {
170  if (!TheSema)
171    return;
172
173  llvm::Timer *CachingTimer = 0;
174  if (TimerGroup.get()) {
175    CachingTimer = new llvm::Timer("Cache global code completions",
176                                   *TimerGroup);
177    CachingTimer->startTimer();
178    Timers.push_back(CachingTimer);
179  }
180
181  // Clear out the previous results.
182  ClearCachedCompletionResults();
183
184  // Gather the set of global code completions.
185  typedef CodeCompletionResult Result;
186  llvm::SmallVector<Result, 8> Results;
187  TheSema->GatherGlobalCodeCompletions(Results);
188
189  // Translate global code completions into cached completions.
190  llvm::DenseMap<CanQualType, unsigned> CompletionTypes;
191
192  for (unsigned I = 0, N = Results.size(); I != N; ++I) {
193    switch (Results[I].Kind) {
194    case Result::RK_Declaration: {
195      bool IsNestedNameSpecifier = false;
196      CachedCodeCompletionResult CachedResult;
197      CachedResult.Completion = Results[I].CreateCodeCompletionString(*TheSema);
198      CachedResult.ShowInContexts = getDeclShowContexts(Results[I].Declaration,
199                                                        Ctx->getLangOptions(),
200                                                        IsNestedNameSpecifier);
201      CachedResult.Priority = Results[I].Priority;
202      CachedResult.Kind = Results[I].CursorKind;
203      CachedResult.Availability = Results[I].Availability;
204
205      // Keep track of the type of this completion in an ASTContext-agnostic
206      // way.
207      QualType UsageType = getDeclUsageType(*Ctx, Results[I].Declaration);
208      if (UsageType.isNull()) {
209        CachedResult.TypeClass = STC_Void;
210        CachedResult.Type = 0;
211      } else {
212        CanQualType CanUsageType
213          = Ctx->getCanonicalType(UsageType.getUnqualifiedType());
214        CachedResult.TypeClass = getSimplifiedTypeClass(CanUsageType);
215
216        // Determine whether we have already seen this type. If so, we save
217        // ourselves the work of formatting the type string by using the
218        // temporary, CanQualType-based hash table to find the associated value.
219        unsigned &TypeValue = CompletionTypes[CanUsageType];
220        if (TypeValue == 0) {
221          TypeValue = CompletionTypes.size();
222          CachedCompletionTypes[QualType(CanUsageType).getAsString()]
223            = TypeValue;
224        }
225
226        CachedResult.Type = TypeValue;
227      }
228
229      CachedCompletionResults.push_back(CachedResult);
230
231      /// Handle nested-name-specifiers in C++.
232      if (TheSema->Context.getLangOptions().CPlusPlus &&
233          IsNestedNameSpecifier && !Results[I].StartsNestedNameSpecifier) {
234        // The contexts in which a nested-name-specifier can appear in C++.
235        unsigned NNSContexts
236          = (1 << (CodeCompletionContext::CCC_TopLevel - 1))
237          | (1 << (CodeCompletionContext::CCC_ObjCIvarList - 1))
238          | (1 << (CodeCompletionContext::CCC_ClassStructUnion - 1))
239          | (1 << (CodeCompletionContext::CCC_Statement - 1))
240          | (1 << (CodeCompletionContext::CCC_Expression - 1))
241          | (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1))
242          | (1 << (CodeCompletionContext::CCC_EnumTag - 1))
243          | (1 << (CodeCompletionContext::CCC_UnionTag - 1))
244          | (1 << (CodeCompletionContext::CCC_ClassOrStructTag - 1))
245          | (1 << (CodeCompletionContext::CCC_Type - 1))
246          | (1 << (CodeCompletionContext::CCC_PotentiallyQualifiedName - 1))
247          | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1));
248
249        if (isa<NamespaceDecl>(Results[I].Declaration) ||
250            isa<NamespaceAliasDecl>(Results[I].Declaration))
251          NNSContexts |= (1 << (CodeCompletionContext::CCC_Namespace - 1));
252
253        if (unsigned RemainingContexts
254                                = NNSContexts & ~CachedResult.ShowInContexts) {
255          // If there any contexts where this completion can be a
256          // nested-name-specifier but isn't already an option, create a
257          // nested-name-specifier completion.
258          Results[I].StartsNestedNameSpecifier = true;
259          CachedResult.Completion = Results[I].CreateCodeCompletionString(*TheSema);
260          CachedResult.ShowInContexts = RemainingContexts;
261          CachedResult.Priority = CCP_NestedNameSpecifier;
262          CachedResult.TypeClass = STC_Void;
263          CachedResult.Type = 0;
264          CachedCompletionResults.push_back(CachedResult);
265        }
266      }
267      break;
268    }
269
270    case Result::RK_Keyword:
271    case Result::RK_Pattern:
272      // Ignore keywords and patterns; we don't care, since they are so
273      // easily regenerated.
274      break;
275
276    case Result::RK_Macro: {
277      CachedCodeCompletionResult CachedResult;
278      CachedResult.Completion = Results[I].CreateCodeCompletionString(*TheSema);
279      CachedResult.ShowInContexts
280        = (1 << (CodeCompletionContext::CCC_TopLevel - 1))
281        | (1 << (CodeCompletionContext::CCC_ObjCInterface - 1))
282        | (1 << (CodeCompletionContext::CCC_ObjCImplementation - 1))
283        | (1 << (CodeCompletionContext::CCC_ObjCIvarList - 1))
284        | (1 << (CodeCompletionContext::CCC_ClassStructUnion - 1))
285        | (1 << (CodeCompletionContext::CCC_Statement - 1))
286        | (1 << (CodeCompletionContext::CCC_Expression - 1))
287        | (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1))
288        | (1 << (CodeCompletionContext::CCC_MacroNameUse - 1))
289        | (1 << (CodeCompletionContext::CCC_PreprocessorExpression - 1))
290        | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1));
291
292
293      CachedResult.Priority = Results[I].Priority;
294      CachedResult.Kind = Results[I].CursorKind;
295      CachedResult.Availability = Results[I].Availability;
296      CachedResult.TypeClass = STC_Void;
297      CachedResult.Type = 0;
298      CachedCompletionResults.push_back(CachedResult);
299      break;
300    }
301    }
302    Results[I].Destroy();
303  }
304
305  if (CachingTimer)
306    CachingTimer->stopTimer();
307
308  // Make a note of the state when we performed this caching.
309  NumTopLevelDeclsAtLastCompletionCache = top_level_size();
310  CacheCodeCompletionCoolDown = 15;
311}
312
313void ASTUnit::ClearCachedCompletionResults() {
314  for (unsigned I = 0, N = CachedCompletionResults.size(); I != N; ++I)
315    delete CachedCompletionResults[I].Completion;
316  CachedCompletionResults.clear();
317  CachedCompletionTypes.clear();
318}
319
320namespace {
321
322/// \brief Gathers information from ASTReader that will be used to initialize
323/// a Preprocessor.
324class ASTInfoCollector : public ASTReaderListener {
325  LangOptions &LangOpt;
326  HeaderSearch &HSI;
327  std::string &TargetTriple;
328  std::string &Predefines;
329  unsigned &Counter;
330
331  unsigned NumHeaderInfos;
332
333public:
334  ASTInfoCollector(LangOptions &LangOpt, HeaderSearch &HSI,
335                   std::string &TargetTriple, std::string &Predefines,
336                   unsigned &Counter)
337    : LangOpt(LangOpt), HSI(HSI), TargetTriple(TargetTriple),
338      Predefines(Predefines), Counter(Counter), NumHeaderInfos(0) {}
339
340  virtual bool ReadLanguageOptions(const LangOptions &LangOpts) {
341    LangOpt = LangOpts;
342    return false;
343  }
344
345  virtual bool ReadTargetTriple(llvm::StringRef Triple) {
346    TargetTriple = Triple;
347    return false;
348  }
349
350  virtual bool ReadPredefinesBuffer(const PCHPredefinesBlocks &Buffers,
351                                    llvm::StringRef OriginalFileName,
352                                    std::string &SuggestedPredefines) {
353    Predefines = Buffers[0].Data;
354    for (unsigned I = 1, N = Buffers.size(); I != N; ++I) {
355      Predefines += Buffers[I].Data;
356    }
357    return false;
358  }
359
360  virtual void ReadHeaderFileInfo(const HeaderFileInfo &HFI, unsigned ID) {
361    HSI.setHeaderFileInfoForUID(HFI, NumHeaderInfos++);
362  }
363
364  virtual void ReadCounter(unsigned Value) {
365    Counter = Value;
366  }
367};
368
369class StoredDiagnosticClient : public DiagnosticClient {
370  llvm::SmallVectorImpl<StoredDiagnostic> &StoredDiags;
371
372public:
373  explicit StoredDiagnosticClient(
374                          llvm::SmallVectorImpl<StoredDiagnostic> &StoredDiags)
375    : StoredDiags(StoredDiags) { }
376
377  virtual void HandleDiagnostic(Diagnostic::Level Level,
378                                const DiagnosticInfo &Info);
379};
380
381/// \brief RAII object that optionally captures diagnostics, if
382/// there is no diagnostic client to capture them already.
383class CaptureDroppedDiagnostics {
384  Diagnostic &Diags;
385  StoredDiagnosticClient Client;
386  DiagnosticClient *PreviousClient;
387
388public:
389  CaptureDroppedDiagnostics(bool RequestCapture, Diagnostic &Diags,
390                           llvm::SmallVectorImpl<StoredDiagnostic> &StoredDiags)
391    : Diags(Diags), Client(StoredDiags), PreviousClient(0)
392  {
393    if (RequestCapture || Diags.getClient() == 0) {
394      PreviousClient = Diags.takeClient();
395      Diags.setClient(&Client);
396    }
397  }
398
399  ~CaptureDroppedDiagnostics() {
400    if (Diags.getClient() == &Client) {
401      Diags.takeClient();
402      Diags.setClient(PreviousClient);
403    }
404  }
405};
406
407} // anonymous namespace
408
409void StoredDiagnosticClient::HandleDiagnostic(Diagnostic::Level Level,
410                                              const DiagnosticInfo &Info) {
411  StoredDiags.push_back(StoredDiagnostic(Level, Info));
412}
413
414const std::string &ASTUnit::getOriginalSourceFileName() {
415  return OriginalSourceFile;
416}
417
418const std::string &ASTUnit::getASTFileName() {
419  assert(isMainFileAST() && "Not an ASTUnit from an AST file!");
420  return static_cast<ASTReader *>(Ctx->getExternalSource())->getFileName();
421}
422
423ASTUnit *ASTUnit::LoadFromASTFile(const std::string &Filename,
424                                  llvm::IntrusiveRefCntPtr<Diagnostic> Diags,
425                                  bool OnlyLocalDecls,
426                                  RemappedFile *RemappedFiles,
427                                  unsigned NumRemappedFiles,
428                                  bool CaptureDiagnostics) {
429  llvm::OwningPtr<ASTUnit> AST(new ASTUnit(true));
430
431  if (!Diags.getPtr()) {
432    // No diagnostics engine was provided, so create our own diagnostics object
433    // with the default options.
434    DiagnosticOptions DiagOpts;
435    Diags = CompilerInstance::createDiagnostics(DiagOpts, 0, 0);
436  }
437
438  AST->CaptureDiagnostics = CaptureDiagnostics;
439  AST->OnlyLocalDecls = OnlyLocalDecls;
440  AST->Diagnostics = Diags;
441  AST->FileMgr.reset(new FileManager);
442  AST->SourceMgr.reset(new SourceManager(AST->getDiagnostics()));
443  AST->HeaderInfo.reset(new HeaderSearch(AST->getFileManager()));
444
445  // If requested, capture diagnostics in the ASTUnit.
446  CaptureDroppedDiagnostics Capture(CaptureDiagnostics, AST->getDiagnostics(),
447                                    AST->StoredDiagnostics);
448
449  for (unsigned I = 0; I != NumRemappedFiles; ++I) {
450    // Create the file entry for the file that we're mapping from.
451    const FileEntry *FromFile
452      = AST->getFileManager().getVirtualFile(RemappedFiles[I].first,
453                                    RemappedFiles[I].second->getBufferSize(),
454                                             0);
455    if (!FromFile) {
456      AST->getDiagnostics().Report(diag::err_fe_remap_missing_from_file)
457        << RemappedFiles[I].first;
458      delete RemappedFiles[I].second;
459      continue;
460    }
461
462    // Override the contents of the "from" file with the contents of
463    // the "to" file.
464    AST->getSourceManager().overrideFileContents(FromFile,
465                                                 RemappedFiles[I].second);
466  }
467
468  // Gather Info for preprocessor construction later on.
469
470  LangOptions LangInfo;
471  HeaderSearch &HeaderInfo = *AST->HeaderInfo.get();
472  std::string TargetTriple;
473  std::string Predefines;
474  unsigned Counter;
475
476  llvm::OwningPtr<ASTReader> Reader;
477
478  Reader.reset(new ASTReader(AST->getSourceManager(), AST->getFileManager(),
479                             AST->getDiagnostics()));
480  Reader->setListener(new ASTInfoCollector(LangInfo, HeaderInfo, TargetTriple,
481                                           Predefines, Counter));
482
483  switch (Reader->ReadAST(Filename, ASTReader::MainFile)) {
484  case ASTReader::Success:
485    break;
486
487  case ASTReader::Failure:
488  case ASTReader::IgnorePCH:
489    AST->getDiagnostics().Report(diag::err_fe_unable_to_load_pch);
490    return NULL;
491  }
492
493  AST->OriginalSourceFile = Reader->getOriginalSourceFile();
494
495  // AST file loaded successfully. Now create the preprocessor.
496
497  // Get information about the target being compiled for.
498  //
499  // FIXME: This is broken, we should store the TargetOptions in the AST file.
500  TargetOptions TargetOpts;
501  TargetOpts.ABI = "";
502  TargetOpts.CXXABI = "";
503  TargetOpts.CPU = "";
504  TargetOpts.Features.clear();
505  TargetOpts.Triple = TargetTriple;
506  AST->Target.reset(TargetInfo::CreateTargetInfo(AST->getDiagnostics(),
507                                                 TargetOpts));
508  AST->PP.reset(new Preprocessor(AST->getDiagnostics(), LangInfo,
509                                 *AST->Target.get(),
510                                 AST->getSourceManager(), HeaderInfo));
511  Preprocessor &PP = *AST->PP.get();
512
513  PP.setPredefines(Reader->getSuggestedPredefines());
514  PP.setCounterValue(Counter);
515  Reader->setPreprocessor(PP);
516
517  // Create and initialize the ASTContext.
518
519  AST->Ctx.reset(new ASTContext(LangInfo,
520                                AST->getSourceManager(),
521                                *AST->Target.get(),
522                                PP.getIdentifierTable(),
523                                PP.getSelectorTable(),
524                                PP.getBuiltinInfo(),
525                                /* size_reserve = */0));
526  ASTContext &Context = *AST->Ctx.get();
527
528  Reader->InitializeContext(Context);
529
530  // Attach the AST reader to the AST context as an external AST
531  // source, so that declarations will be deserialized from the
532  // AST file as needed.
533  ASTReader *ReaderPtr = Reader.get();
534  llvm::OwningPtr<ExternalASTSource> Source(Reader.take());
535  Context.setExternalSource(Source);
536
537  // Create an AST consumer, even though it isn't used.
538  AST->Consumer.reset(new ASTConsumer);
539
540  // Create a semantic analysis object and tell the AST reader about it.
541  AST->TheSema.reset(new Sema(PP, Context, *AST->Consumer));
542  AST->TheSema->Initialize();
543  ReaderPtr->InitializeSema(*AST->TheSema);
544
545  return AST.take();
546}
547
548namespace {
549
550class TopLevelDeclTrackerConsumer : public ASTConsumer {
551  ASTUnit &Unit;
552
553public:
554  TopLevelDeclTrackerConsumer(ASTUnit &_Unit) : Unit(_Unit) {}
555
556  void HandleTopLevelDecl(DeclGroupRef D) {
557    for (DeclGroupRef::iterator it = D.begin(), ie = D.end(); it != ie; ++it) {
558      Decl *D = *it;
559      // FIXME: Currently ObjC method declarations are incorrectly being
560      // reported as top-level declarations, even though their DeclContext
561      // is the containing ObjC @interface/@implementation.  This is a
562      // fundamental problem in the parser right now.
563      if (isa<ObjCMethodDecl>(D))
564        continue;
565      Unit.addTopLevelDecl(D);
566    }
567  }
568
569  // We're not interested in "interesting" decls.
570  void HandleInterestingDecl(DeclGroupRef) {}
571};
572
573class TopLevelDeclTrackerAction : public ASTFrontendAction {
574public:
575  ASTUnit &Unit;
576
577  virtual ASTConsumer *CreateASTConsumer(CompilerInstance &CI,
578                                         llvm::StringRef InFile) {
579    return new TopLevelDeclTrackerConsumer(Unit);
580  }
581
582public:
583  TopLevelDeclTrackerAction(ASTUnit &_Unit) : Unit(_Unit) {}
584
585  virtual bool hasCodeCompletionSupport() const { return false; }
586  virtual bool usesCompleteTranslationUnit()  {
587    return Unit.isCompleteTranslationUnit();
588  }
589};
590
591class PrecompilePreambleConsumer : public PCHGenerator {
592  ASTUnit &Unit;
593  std::vector<Decl *> TopLevelDecls;
594
595public:
596  PrecompilePreambleConsumer(ASTUnit &Unit,
597                             const Preprocessor &PP, bool Chaining,
598                             const char *isysroot, llvm::raw_ostream *Out)
599    : PCHGenerator(PP, Chaining, isysroot, Out), Unit(Unit) { }
600
601  virtual void HandleTopLevelDecl(DeclGroupRef D) {
602    for (DeclGroupRef::iterator it = D.begin(), ie = D.end(); it != ie; ++it) {
603      Decl *D = *it;
604      // FIXME: Currently ObjC method declarations are incorrectly being
605      // reported as top-level declarations, even though their DeclContext
606      // is the containing ObjC @interface/@implementation.  This is a
607      // fundamental problem in the parser right now.
608      if (isa<ObjCMethodDecl>(D))
609        continue;
610      TopLevelDecls.push_back(D);
611    }
612  }
613
614  virtual void HandleTranslationUnit(ASTContext &Ctx) {
615    PCHGenerator::HandleTranslationUnit(Ctx);
616    if (!Unit.getDiagnostics().hasErrorOccurred()) {
617      // Translate the top-level declarations we captured during
618      // parsing into declaration IDs in the precompiled
619      // preamble. This will allow us to deserialize those top-level
620      // declarations when requested.
621      for (unsigned I = 0, N = TopLevelDecls.size(); I != N; ++I)
622        Unit.addTopLevelDeclFromPreamble(
623                                      getWriter().getDeclID(TopLevelDecls[I]));
624    }
625  }
626};
627
628class PrecompilePreambleAction : public ASTFrontendAction {
629  ASTUnit &Unit;
630
631public:
632  explicit PrecompilePreambleAction(ASTUnit &Unit) : Unit(Unit) {}
633
634  virtual ASTConsumer *CreateASTConsumer(CompilerInstance &CI,
635                                         llvm::StringRef InFile) {
636    std::string Sysroot;
637    llvm::raw_ostream *OS = 0;
638    bool Chaining;
639    if (GeneratePCHAction::ComputeASTConsumerArguments(CI, InFile, Sysroot,
640                                                       OS, Chaining))
641      return 0;
642
643    const char *isysroot = CI.getFrontendOpts().RelocatablePCH ?
644                             Sysroot.c_str() : 0;
645    return new PrecompilePreambleConsumer(Unit, CI.getPreprocessor(), Chaining,
646                                          isysroot, OS);
647  }
648
649  virtual bool hasCodeCompletionSupport() const { return false; }
650  virtual bool hasASTFileSupport() const { return false; }
651  virtual bool usesCompleteTranslationUnit() { return false; }
652};
653
654}
655
656/// Parse the source file into a translation unit using the given compiler
657/// invocation, replacing the current translation unit.
658///
659/// \returns True if a failure occurred that causes the ASTUnit not to
660/// contain any translation-unit information, false otherwise.
661bool ASTUnit::Parse(llvm::MemoryBuffer *OverrideMainBuffer) {
662  delete SavedMainFileBuffer;
663  SavedMainFileBuffer = 0;
664
665  if (!Invocation.get()) {
666    delete OverrideMainBuffer;
667    return true;
668  }
669
670  // Create the compiler instance to use for building the AST.
671  CompilerInstance Clang;
672  Clang.setInvocation(Invocation.take());
673  OriginalSourceFile = Clang.getFrontendOpts().Inputs[0].second;
674
675  // Set up diagnostics, capturing any diagnostics that would
676  // otherwise be dropped.
677  Clang.setDiagnostics(&getDiagnostics());
678  CaptureDroppedDiagnostics Capture(CaptureDiagnostics,
679                                    getDiagnostics(),
680                                    StoredDiagnostics);
681
682  // Create the target instance.
683  Clang.setTarget(TargetInfo::CreateTargetInfo(Clang.getDiagnostics(),
684                                               Clang.getTargetOpts()));
685  if (!Clang.hasTarget()) {
686    delete OverrideMainBuffer;
687    return true;
688  }
689
690  // Inform the target of the language options.
691  //
692  // FIXME: We shouldn't need to do this, the target should be immutable once
693  // created. This complexity should be lifted elsewhere.
694  Clang.getTarget().setForcedLangOptions(Clang.getLangOpts());
695
696  assert(Clang.getFrontendOpts().Inputs.size() == 1 &&
697         "Invocation must have exactly one source file!");
698  assert(Clang.getFrontendOpts().Inputs[0].first != IK_AST &&
699         "FIXME: AST inputs not yet supported here!");
700  assert(Clang.getFrontendOpts().Inputs[0].first != IK_LLVM_IR &&
701         "IR inputs not support here!");
702
703  // Configure the various subsystems.
704  // FIXME: Should we retain the previous file manager?
705  FileMgr.reset(new FileManager);
706  SourceMgr.reset(new SourceManager(getDiagnostics()));
707  TheSema.reset();
708  Ctx.reset();
709  PP.reset();
710
711  // Clear out old caches and data.
712  TopLevelDecls.clear();
713  CleanTemporaryFiles();
714  PreprocessedEntitiesByFile.clear();
715
716  if (!OverrideMainBuffer) {
717    StoredDiagnostics.clear();
718    TopLevelDeclsInPreamble.clear();
719  }
720
721  // Create a file manager object to provide access to and cache the filesystem.
722  Clang.setFileManager(&getFileManager());
723
724  // Create the source manager.
725  Clang.setSourceManager(&getSourceManager());
726
727  // If the main file has been overridden due to the use of a preamble,
728  // make that override happen and introduce the preamble.
729  PreprocessorOptions &PreprocessorOpts = Clang.getPreprocessorOpts();
730  std::string PriorImplicitPCHInclude;
731  if (OverrideMainBuffer) {
732    PreprocessorOpts.addRemappedFile(OriginalSourceFile, OverrideMainBuffer);
733    PreprocessorOpts.PrecompiledPreambleBytes.first = Preamble.size();
734    PreprocessorOpts.PrecompiledPreambleBytes.second
735                                                    = PreambleEndsAtStartOfLine;
736    PriorImplicitPCHInclude = PreprocessorOpts.ImplicitPCHInclude;
737    PreprocessorOpts.ImplicitPCHInclude = PreambleFile;
738    PreprocessorOpts.DisablePCHValidation = true;
739
740    // Keep track of the override buffer;
741    SavedMainFileBuffer = OverrideMainBuffer;
742
743    // The stored diagnostic has the old source manager in it; update
744    // the locations to refer into the new source manager. Since we've
745    // been careful to make sure that the source manager's state
746    // before and after are identical, so that we can reuse the source
747    // location itself.
748    for (unsigned I = 0, N = StoredDiagnostics.size(); I != N; ++I) {
749      FullSourceLoc Loc(StoredDiagnostics[I].getLocation(),
750                        getSourceManager());
751      StoredDiagnostics[I].setLocation(Loc);
752    }
753  } else {
754    PreprocessorOpts.PrecompiledPreambleBytes.first = 0;
755    PreprocessorOpts.PrecompiledPreambleBytes.second = false;
756  }
757
758  llvm::OwningPtr<TopLevelDeclTrackerAction> Act;
759  Act.reset(new TopLevelDeclTrackerAction(*this));
760  if (!Act->BeginSourceFile(Clang, Clang.getFrontendOpts().Inputs[0].second,
761                            Clang.getFrontendOpts().Inputs[0].first))
762    goto error;
763
764  Act->Execute();
765
766  // Steal the created target, context, and preprocessor, and take back the
767  // source and file managers.
768  TheSema.reset(Clang.takeSema());
769  Consumer.reset(Clang.takeASTConsumer());
770  Ctx.reset(Clang.takeASTContext());
771  PP.reset(Clang.takePreprocessor());
772  Clang.takeSourceManager();
773  Clang.takeFileManager();
774  Target.reset(Clang.takeTarget());
775
776  Act->EndSourceFile();
777
778  // Remove the overridden buffer we used for the preamble.
779  if (OverrideMainBuffer) {
780    PreprocessorOpts.eraseRemappedFile(
781                               PreprocessorOpts.remapped_file_buffer_end() - 1);
782    PreprocessorOpts.ImplicitPCHInclude = PriorImplicitPCHInclude;
783  }
784
785  Invocation.reset(Clang.takeInvocation());
786
787  // If we were asked to cache code-completion results and don't have any
788  // results yet, do so now.
789  if (ShouldCacheCodeCompletionResults && CachedCompletionResults.empty())
790    CacheCodeCompletionResults();
791
792  return false;
793
794error:
795  // Remove the overridden buffer we used for the preamble.
796  if (OverrideMainBuffer) {
797    PreprocessorOpts.eraseRemappedFile(
798                               PreprocessorOpts.remapped_file_buffer_end() - 1);
799    PreprocessorOpts.DisablePCHValidation = true;
800    PreprocessorOpts.ImplicitPCHInclude = PriorImplicitPCHInclude;
801    delete OverrideMainBuffer;
802    SavedMainFileBuffer = 0;
803  }
804
805  Clang.takeSourceManager();
806  Clang.takeFileManager();
807  Invocation.reset(Clang.takeInvocation());
808  return true;
809}
810
811/// \brief Simple function to retrieve a path for a preamble precompiled header.
812static std::string GetPreamblePCHPath() {
813  // FIXME: This is lame; sys::Path should provide this function (in particular,
814  // it should know how to find the temporary files dir).
815  // FIXME: This is really lame. I copied this code from the Driver!
816  // FIXME: This is a hack so that we can override the preamble file during
817  // crash-recovery testing, which is the only case where the preamble files
818  // are not necessarily cleaned up.
819  const char *TmpFile = ::getenv("CINDEXTEST_PREAMBLE_FILE");
820  if (TmpFile)
821    return TmpFile;
822
823  std::string Error;
824  const char *TmpDir = ::getenv("TMPDIR");
825  if (!TmpDir)
826    TmpDir = ::getenv("TEMP");
827  if (!TmpDir)
828    TmpDir = ::getenv("TMP");
829#ifdef LLVM_ON_WIN32
830  if (!TmpDir)
831    TmpDir = ::getenv("USERPROFILE");
832#endif
833  if (!TmpDir)
834    TmpDir = "/tmp";
835  llvm::sys::Path P(TmpDir);
836  P.createDirectoryOnDisk(true);
837  P.appendComponent("preamble");
838  P.appendSuffix("pch");
839  if (P.createTemporaryFileOnDisk())
840    return std::string();
841
842  return P.str();
843}
844
845/// \brief Compute the preamble for the main file, providing the source buffer
846/// that corresponds to the main file along with a pair (bytes, start-of-line)
847/// that describes the preamble.
848std::pair<llvm::MemoryBuffer *, std::pair<unsigned, bool> >
849ASTUnit::ComputePreamble(CompilerInvocation &Invocation,
850                         unsigned MaxLines, bool &CreatedBuffer) {
851  FrontendOptions &FrontendOpts = Invocation.getFrontendOpts();
852  PreprocessorOptions &PreprocessorOpts
853    = Invocation.getPreprocessorOpts();
854  CreatedBuffer = false;
855
856  // Try to determine if the main file has been remapped, either from the
857  // command line (to another file) or directly through the compiler invocation
858  // (to a memory buffer).
859  llvm::MemoryBuffer *Buffer = 0;
860  llvm::sys::PathWithStatus MainFilePath(FrontendOpts.Inputs[0].second);
861  if (const llvm::sys::FileStatus *MainFileStatus = MainFilePath.getFileStatus()) {
862    // Check whether there is a file-file remapping of the main file
863    for (PreprocessorOptions::remapped_file_iterator
864          M = PreprocessorOpts.remapped_file_begin(),
865          E = PreprocessorOpts.remapped_file_end();
866         M != E;
867         ++M) {
868      llvm::sys::PathWithStatus MPath(M->first);
869      if (const llvm::sys::FileStatus *MStatus = MPath.getFileStatus()) {
870        if (MainFileStatus->uniqueID == MStatus->uniqueID) {
871          // We found a remapping. Try to load the resulting, remapped source.
872          if (CreatedBuffer) {
873            delete Buffer;
874            CreatedBuffer = false;
875          }
876
877          Buffer = llvm::MemoryBuffer::getFile(M->second);
878          if (!Buffer)
879            return std::make_pair((llvm::MemoryBuffer*)0,
880                                  std::make_pair(0, true));
881          CreatedBuffer = true;
882        }
883      }
884    }
885
886    // Check whether there is a file-buffer remapping. It supercedes the
887    // file-file remapping.
888    for (PreprocessorOptions::remapped_file_buffer_iterator
889           M = PreprocessorOpts.remapped_file_buffer_begin(),
890           E = PreprocessorOpts.remapped_file_buffer_end();
891         M != E;
892         ++M) {
893      llvm::sys::PathWithStatus MPath(M->first);
894      if (const llvm::sys::FileStatus *MStatus = MPath.getFileStatus()) {
895        if (MainFileStatus->uniqueID == MStatus->uniqueID) {
896          // We found a remapping.
897          if (CreatedBuffer) {
898            delete Buffer;
899            CreatedBuffer = false;
900          }
901
902          Buffer = const_cast<llvm::MemoryBuffer *>(M->second);
903        }
904      }
905    }
906  }
907
908  // If the main source file was not remapped, load it now.
909  if (!Buffer) {
910    Buffer = llvm::MemoryBuffer::getFile(FrontendOpts.Inputs[0].second);
911    if (!Buffer)
912      return std::make_pair((llvm::MemoryBuffer*)0, std::make_pair(0, true));
913
914    CreatedBuffer = true;
915  }
916
917  return std::make_pair(Buffer, Lexer::ComputePreamble(Buffer, MaxLines));
918}
919
920static llvm::MemoryBuffer *CreatePaddedMainFileBuffer(llvm::MemoryBuffer *Old,
921                                                      bool DeleteOld,
922                                                      unsigned NewSize,
923                                                      llvm::StringRef NewName) {
924  llvm::MemoryBuffer *Result
925    = llvm::MemoryBuffer::getNewUninitMemBuffer(NewSize, NewName);
926  memcpy(const_cast<char*>(Result->getBufferStart()),
927         Old->getBufferStart(), Old->getBufferSize());
928  memset(const_cast<char*>(Result->getBufferStart()) + Old->getBufferSize(),
929         ' ', NewSize - Old->getBufferSize() - 1);
930  const_cast<char*>(Result->getBufferEnd())[-1] = '\n';
931
932  if (DeleteOld)
933    delete Old;
934
935  return Result;
936}
937
938/// \brief Attempt to build or re-use a precompiled preamble when (re-)parsing
939/// the source file.
940///
941/// This routine will compute the preamble of the main source file. If a
942/// non-trivial preamble is found, it will precompile that preamble into a
943/// precompiled header so that the precompiled preamble can be used to reduce
944/// reparsing time. If a precompiled preamble has already been constructed,
945/// this routine will determine if it is still valid and, if so, avoid
946/// rebuilding the precompiled preamble.
947///
948/// \param AllowRebuild When true (the default), this routine is
949/// allowed to rebuild the precompiled preamble if it is found to be
950/// out-of-date.
951///
952/// \param MaxLines When non-zero, the maximum number of lines that
953/// can occur within the preamble.
954///
955/// \returns If the precompiled preamble can be used, returns a newly-allocated
956/// buffer that should be used in place of the main file when doing so.
957/// Otherwise, returns a NULL pointer.
958llvm::MemoryBuffer *ASTUnit::getMainBufferWithPrecompiledPreamble(
959                                          CompilerInvocation PreambleInvocation,
960                                                           bool AllowRebuild,
961                                                           unsigned MaxLines) {
962  FrontendOptions &FrontendOpts = PreambleInvocation.getFrontendOpts();
963  PreprocessorOptions &PreprocessorOpts
964    = PreambleInvocation.getPreprocessorOpts();
965
966  bool CreatedPreambleBuffer = false;
967  std::pair<llvm::MemoryBuffer *, std::pair<unsigned, bool> > NewPreamble
968    = ComputePreamble(PreambleInvocation, MaxLines, CreatedPreambleBuffer);
969
970  if (!NewPreamble.second.first) {
971    // We couldn't find a preamble in the main source. Clear out the current
972    // preamble, if we have one. It's obviously no good any more.
973    Preamble.clear();
974    if (!PreambleFile.empty()) {
975      llvm::sys::Path(PreambleFile).eraseFromDisk();
976      PreambleFile.clear();
977    }
978    if (CreatedPreambleBuffer)
979      delete NewPreamble.first;
980
981    // The next time we actually see a preamble, precompile it.
982    PreambleRebuildCounter = 1;
983    return 0;
984  }
985
986  if (!Preamble.empty()) {
987    // We've previously computed a preamble. Check whether we have the same
988    // preamble now that we did before, and that there's enough space in
989    // the main-file buffer within the precompiled preamble to fit the
990    // new main file.
991    if (Preamble.size() == NewPreamble.second.first &&
992        PreambleEndsAtStartOfLine == NewPreamble.second.second &&
993        NewPreamble.first->getBufferSize() < PreambleReservedSize-2 &&
994        memcmp(&Preamble[0], NewPreamble.first->getBufferStart(),
995               NewPreamble.second.first) == 0) {
996      // The preamble has not changed. We may be able to re-use the precompiled
997      // preamble.
998
999      // Check that none of the files used by the preamble have changed.
1000      bool AnyFileChanged = false;
1001
1002      // First, make a record of those files that have been overridden via
1003      // remapping or unsaved_files.
1004      llvm::StringMap<std::pair<off_t, time_t> > OverriddenFiles;
1005      for (PreprocessorOptions::remapped_file_iterator
1006                R = PreprocessorOpts.remapped_file_begin(),
1007             REnd = PreprocessorOpts.remapped_file_end();
1008           !AnyFileChanged && R != REnd;
1009           ++R) {
1010        struct stat StatBuf;
1011        if (stat(R->second.c_str(), &StatBuf)) {
1012          // If we can't stat the file we're remapping to, assume that something
1013          // horrible happened.
1014          AnyFileChanged = true;
1015          break;
1016        }
1017
1018        OverriddenFiles[R->first] = std::make_pair(StatBuf.st_size,
1019                                                   StatBuf.st_mtime);
1020      }
1021      for (PreprocessorOptions::remapped_file_buffer_iterator
1022                R = PreprocessorOpts.remapped_file_buffer_begin(),
1023             REnd = PreprocessorOpts.remapped_file_buffer_end();
1024           !AnyFileChanged && R != REnd;
1025           ++R) {
1026        // FIXME: Should we actually compare the contents of file->buffer
1027        // remappings?
1028        OverriddenFiles[R->first] = std::make_pair(R->second->getBufferSize(),
1029                                                   0);
1030      }
1031
1032      // Check whether anything has changed.
1033      for (llvm::StringMap<std::pair<off_t, time_t> >::iterator
1034             F = FilesInPreamble.begin(), FEnd = FilesInPreamble.end();
1035           !AnyFileChanged && F != FEnd;
1036           ++F) {
1037        llvm::StringMap<std::pair<off_t, time_t> >::iterator Overridden
1038          = OverriddenFiles.find(F->first());
1039        if (Overridden != OverriddenFiles.end()) {
1040          // This file was remapped; check whether the newly-mapped file
1041          // matches up with the previous mapping.
1042          if (Overridden->second != F->second)
1043            AnyFileChanged = true;
1044          continue;
1045        }
1046
1047        // The file was not remapped; check whether it has changed on disk.
1048        struct stat StatBuf;
1049        if (stat(F->first(), &StatBuf)) {
1050          // If we can't stat the file, assume that something horrible happened.
1051          AnyFileChanged = true;
1052        } else if (StatBuf.st_size != F->second.first ||
1053                   StatBuf.st_mtime != F->second.second)
1054          AnyFileChanged = true;
1055      }
1056
1057      if (!AnyFileChanged) {
1058        // Okay! We can re-use the precompiled preamble.
1059
1060        // Set the state of the diagnostic object to mimic its state
1061        // after parsing the preamble.
1062        // FIXME: This won't catch any #pragma push warning changes that
1063        // have occurred in the preamble.
1064        getDiagnostics().Reset();
1065        ProcessWarningOptions(getDiagnostics(),
1066                              PreambleInvocation.getDiagnosticOpts());
1067        getDiagnostics().setNumWarnings(NumWarningsInPreamble);
1068        if (StoredDiagnostics.size() > NumStoredDiagnosticsInPreamble)
1069          StoredDiagnostics.erase(
1070            StoredDiagnostics.begin() + NumStoredDiagnosticsInPreamble,
1071                                  StoredDiagnostics.end());
1072
1073        // Create a version of the main file buffer that is padded to
1074        // buffer size we reserved when creating the preamble.
1075        return CreatePaddedMainFileBuffer(NewPreamble.first,
1076                                          CreatedPreambleBuffer,
1077                                          PreambleReservedSize,
1078                                          FrontendOpts.Inputs[0].second);
1079      }
1080    }
1081
1082    // If we aren't allowed to rebuild the precompiled preamble, just
1083    // return now.
1084    if (!AllowRebuild)
1085      return 0;
1086
1087    // We can't reuse the previously-computed preamble. Build a new one.
1088    Preamble.clear();
1089    llvm::sys::Path(PreambleFile).eraseFromDisk();
1090    PreambleRebuildCounter = 1;
1091  } else if (!AllowRebuild) {
1092    // We aren't allowed to rebuild the precompiled preamble; just
1093    // return now.
1094    return 0;
1095  }
1096
1097  // If the preamble rebuild counter > 1, it's because we previously
1098  // failed to build a preamble and we're not yet ready to try
1099  // again. Decrement the counter and return a failure.
1100  if (PreambleRebuildCounter > 1) {
1101    --PreambleRebuildCounter;
1102    return 0;
1103  }
1104
1105  // Create a temporary file for the precompiled preamble. In rare
1106  // circumstances, this can fail.
1107  std::string PreamblePCHPath = GetPreamblePCHPath();
1108  if (PreamblePCHPath.empty()) {
1109    // Try again next time.
1110    PreambleRebuildCounter = 1;
1111    return 0;
1112  }
1113
1114  // We did not previously compute a preamble, or it can't be reused anyway.
1115  llvm::Timer *PreambleTimer = 0;
1116  if (TimerGroup.get()) {
1117    PreambleTimer = new llvm::Timer("Precompiling preamble", *TimerGroup);
1118    PreambleTimer->startTimer();
1119    Timers.push_back(PreambleTimer);
1120  }
1121
1122  // Create a new buffer that stores the preamble. The buffer also contains
1123  // extra space for the original contents of the file (which will be present
1124  // when we actually parse the file) along with more room in case the file
1125  // grows.
1126  PreambleReservedSize = NewPreamble.first->getBufferSize();
1127  if (PreambleReservedSize < 4096)
1128    PreambleReservedSize = 8191;
1129  else
1130    PreambleReservedSize *= 2;
1131
1132  // Save the preamble text for later; we'll need to compare against it for
1133  // subsequent reparses.
1134  Preamble.assign(NewPreamble.first->getBufferStart(),
1135                  NewPreamble.first->getBufferStart()
1136                                                  + NewPreamble.second.first);
1137  PreambleEndsAtStartOfLine = NewPreamble.second.second;
1138
1139  delete PreambleBuffer;
1140  PreambleBuffer
1141    = llvm::MemoryBuffer::getNewUninitMemBuffer(PreambleReservedSize,
1142                                                FrontendOpts.Inputs[0].second);
1143  memcpy(const_cast<char*>(PreambleBuffer->getBufferStart()),
1144         NewPreamble.first->getBufferStart(), Preamble.size());
1145  memset(const_cast<char*>(PreambleBuffer->getBufferStart()) + Preamble.size(),
1146         ' ', PreambleReservedSize - Preamble.size() - 1);
1147  const_cast<char*>(PreambleBuffer->getBufferEnd())[-1] = '\n';
1148
1149  // Remap the main source file to the preamble buffer.
1150  llvm::sys::PathWithStatus MainFilePath(FrontendOpts.Inputs[0].second);
1151  PreprocessorOpts.addRemappedFile(MainFilePath.str(), PreambleBuffer);
1152
1153  // Tell the compiler invocation to generate a temporary precompiled header.
1154  FrontendOpts.ProgramAction = frontend::GeneratePCH;
1155  FrontendOpts.ChainedPCH = true;
1156  // FIXME: Generate the precompiled header into memory?
1157  FrontendOpts.OutputFile = PreamblePCHPath;
1158  PreprocessorOpts.PrecompiledPreambleBytes.first = 0;
1159  PreprocessorOpts.PrecompiledPreambleBytes.second = false;
1160
1161  // Create the compiler instance to use for building the precompiled preamble.
1162  CompilerInstance Clang;
1163  Clang.setInvocation(&PreambleInvocation);
1164  OriginalSourceFile = Clang.getFrontendOpts().Inputs[0].second;
1165
1166  // Set up diagnostics, capturing all of the diagnostics produced.
1167  Clang.setDiagnostics(&getDiagnostics());
1168  CaptureDroppedDiagnostics Capture(CaptureDiagnostics,
1169                                    getDiagnostics(),
1170                                    StoredDiagnostics);
1171
1172  // Create the target instance.
1173  Clang.setTarget(TargetInfo::CreateTargetInfo(Clang.getDiagnostics(),
1174                                               Clang.getTargetOpts()));
1175  if (!Clang.hasTarget()) {
1176    llvm::sys::Path(FrontendOpts.OutputFile).eraseFromDisk();
1177    Preamble.clear();
1178    if (CreatedPreambleBuffer)
1179      delete NewPreamble.first;
1180    if (PreambleTimer)
1181      PreambleTimer->stopTimer();
1182    PreambleRebuildCounter = DefaultPreambleRebuildInterval;
1183    PreprocessorOpts.eraseRemappedFile(
1184                               PreprocessorOpts.remapped_file_buffer_end() - 1);
1185    return 0;
1186  }
1187
1188  // Inform the target of the language options.
1189  //
1190  // FIXME: We shouldn't need to do this, the target should be immutable once
1191  // created. This complexity should be lifted elsewhere.
1192  Clang.getTarget().setForcedLangOptions(Clang.getLangOpts());
1193
1194  assert(Clang.getFrontendOpts().Inputs.size() == 1 &&
1195         "Invocation must have exactly one source file!");
1196  assert(Clang.getFrontendOpts().Inputs[0].first != IK_AST &&
1197         "FIXME: AST inputs not yet supported here!");
1198  assert(Clang.getFrontendOpts().Inputs[0].first != IK_LLVM_IR &&
1199         "IR inputs not support here!");
1200
1201  // Clear out old caches and data.
1202  getDiagnostics().Reset();
1203  ProcessWarningOptions(getDiagnostics(), Clang.getDiagnosticOpts());
1204  StoredDiagnostics.clear();
1205  TopLevelDecls.clear();
1206  TopLevelDeclsInPreamble.clear();
1207
1208  // Create a file manager object to provide access to and cache the filesystem.
1209  Clang.setFileManager(new FileManager);
1210
1211  // Create the source manager.
1212  Clang.setSourceManager(new SourceManager(getDiagnostics()));
1213
1214  llvm::OwningPtr<PrecompilePreambleAction> Act;
1215  Act.reset(new PrecompilePreambleAction(*this));
1216  if (!Act->BeginSourceFile(Clang, Clang.getFrontendOpts().Inputs[0].second,
1217                            Clang.getFrontendOpts().Inputs[0].first)) {
1218    Clang.takeInvocation();
1219    llvm::sys::Path(FrontendOpts.OutputFile).eraseFromDisk();
1220    Preamble.clear();
1221    if (CreatedPreambleBuffer)
1222      delete NewPreamble.first;
1223    if (PreambleTimer)
1224      PreambleTimer->stopTimer();
1225    PreambleRebuildCounter = DefaultPreambleRebuildInterval;
1226    PreprocessorOpts.eraseRemappedFile(
1227                               PreprocessorOpts.remapped_file_buffer_end() - 1);
1228    return 0;
1229  }
1230
1231  Act->Execute();
1232  Act->EndSourceFile();
1233  Clang.takeInvocation();
1234
1235  if (Diagnostics->hasErrorOccurred()) {
1236    // There were errors parsing the preamble, so no precompiled header was
1237    // generated. Forget that we even tried.
1238    // FIXME: Should we leave a note for ourselves to try again?
1239    llvm::sys::Path(FrontendOpts.OutputFile).eraseFromDisk();
1240    Preamble.clear();
1241    if (CreatedPreambleBuffer)
1242      delete NewPreamble.first;
1243    if (PreambleTimer)
1244      PreambleTimer->stopTimer();
1245    TopLevelDeclsInPreamble.clear();
1246    PreambleRebuildCounter = DefaultPreambleRebuildInterval;
1247    PreprocessorOpts.eraseRemappedFile(
1248                               PreprocessorOpts.remapped_file_buffer_end() - 1);
1249    return 0;
1250  }
1251
1252  // Keep track of the preamble we precompiled.
1253  PreambleFile = FrontendOpts.OutputFile;
1254  NumStoredDiagnosticsInPreamble = StoredDiagnostics.size();
1255  NumWarningsInPreamble = getDiagnostics().getNumWarnings();
1256
1257  // Keep track of all of the files that the source manager knows about,
1258  // so we can verify whether they have changed or not.
1259  FilesInPreamble.clear();
1260  SourceManager &SourceMgr = Clang.getSourceManager();
1261  const llvm::MemoryBuffer *MainFileBuffer
1262    = SourceMgr.getBuffer(SourceMgr.getMainFileID());
1263  for (SourceManager::fileinfo_iterator F = SourceMgr.fileinfo_begin(),
1264                                     FEnd = SourceMgr.fileinfo_end();
1265       F != FEnd;
1266       ++F) {
1267    const FileEntry *File = F->second->Entry;
1268    if (!File || F->second->getRawBuffer() == MainFileBuffer)
1269      continue;
1270
1271    FilesInPreamble[File->getName()]
1272      = std::make_pair(F->second->getSize(), File->getModificationTime());
1273  }
1274
1275  if (PreambleTimer)
1276    PreambleTimer->stopTimer();
1277
1278  PreambleRebuildCounter = 1;
1279  PreprocessorOpts.eraseRemappedFile(
1280                               PreprocessorOpts.remapped_file_buffer_end() - 1);
1281  return CreatePaddedMainFileBuffer(NewPreamble.first,
1282                                    CreatedPreambleBuffer,
1283                                    PreambleReservedSize,
1284                                    FrontendOpts.Inputs[0].second);
1285}
1286
1287void ASTUnit::RealizeTopLevelDeclsFromPreamble() {
1288  std::vector<Decl *> Resolved;
1289  Resolved.reserve(TopLevelDeclsInPreamble.size());
1290  ExternalASTSource &Source = *getASTContext().getExternalSource();
1291  for (unsigned I = 0, N = TopLevelDeclsInPreamble.size(); I != N; ++I) {
1292    // Resolve the declaration ID to an actual declaration, possibly
1293    // deserializing the declaration in the process.
1294    Decl *D = Source.GetExternalDecl(TopLevelDeclsInPreamble[I]);
1295    if (D)
1296      Resolved.push_back(D);
1297  }
1298  TopLevelDeclsInPreamble.clear();
1299  TopLevelDecls.insert(TopLevelDecls.begin(), Resolved.begin(), Resolved.end());
1300}
1301
1302unsigned ASTUnit::getMaxPCHLevel() const {
1303  if (!getOnlyLocalDecls())
1304    return Decl::MaxPCHLevel;
1305
1306  return 0;
1307}
1308
1309ASTUnit *ASTUnit::LoadFromCompilerInvocation(CompilerInvocation *CI,
1310                                   llvm::IntrusiveRefCntPtr<Diagnostic> Diags,
1311                                             bool OnlyLocalDecls,
1312                                             bool CaptureDiagnostics,
1313                                             bool PrecompilePreamble,
1314                                             bool CompleteTranslationUnit,
1315                                             bool CacheCodeCompletionResults) {
1316  if (!Diags.getPtr()) {
1317    // No diagnostics engine was provided, so create our own diagnostics object
1318    // with the default options.
1319    DiagnosticOptions DiagOpts;
1320    Diags = CompilerInstance::createDiagnostics(DiagOpts, 0, 0);
1321  }
1322
1323  // Create the AST unit.
1324  llvm::OwningPtr<ASTUnit> AST;
1325  AST.reset(new ASTUnit(false));
1326  AST->Diagnostics = Diags;
1327  AST->CaptureDiagnostics = CaptureDiagnostics;
1328  AST->OnlyLocalDecls = OnlyLocalDecls;
1329  AST->CompleteTranslationUnit = CompleteTranslationUnit;
1330  AST->ShouldCacheCodeCompletionResults = CacheCodeCompletionResults;
1331  AST->Invocation.reset(CI);
1332  CI->getPreprocessorOpts().RetainRemappedFileBuffers = true;
1333
1334  if (getenv("LIBCLANG_TIMING"))
1335    AST->TimerGroup.reset(
1336                  new llvm::TimerGroup(CI->getFrontendOpts().Inputs[0].second));
1337
1338
1339  llvm::MemoryBuffer *OverrideMainBuffer = 0;
1340  // FIXME: When C++ PCH is ready, allow use of it for a precompiled preamble.
1341  if (PrecompilePreamble && !CI->getLangOpts().CPlusPlus) {
1342    AST->PreambleRebuildCounter = 1;
1343    OverrideMainBuffer
1344      = AST->getMainBufferWithPrecompiledPreamble(*AST->Invocation);
1345  }
1346
1347  llvm::Timer *ParsingTimer = 0;
1348  if (AST->TimerGroup.get()) {
1349    ParsingTimer = new llvm::Timer("Initial parse", *AST->TimerGroup);
1350    ParsingTimer->startTimer();
1351    AST->Timers.push_back(ParsingTimer);
1352  }
1353
1354  bool Failed = AST->Parse(OverrideMainBuffer);
1355  if (ParsingTimer)
1356    ParsingTimer->stopTimer();
1357
1358  return Failed? 0 : AST.take();
1359}
1360
1361ASTUnit *ASTUnit::LoadFromCommandLine(const char **ArgBegin,
1362                                      const char **ArgEnd,
1363                                    llvm::IntrusiveRefCntPtr<Diagnostic> Diags,
1364                                      llvm::StringRef ResourceFilesPath,
1365                                      bool OnlyLocalDecls,
1366                                      RemappedFile *RemappedFiles,
1367                                      unsigned NumRemappedFiles,
1368                                      bool CaptureDiagnostics,
1369                                      bool PrecompilePreamble,
1370                                      bool CompleteTranslationUnit,
1371                                      bool CacheCodeCompletionResults) {
1372  bool CreatedDiagnosticsObject = false;
1373
1374  if (!Diags.getPtr()) {
1375    // No diagnostics engine was provided, so create our own diagnostics object
1376    // with the default options.
1377    DiagnosticOptions DiagOpts;
1378    Diags = CompilerInstance::createDiagnostics(DiagOpts, 0, 0);
1379    CreatedDiagnosticsObject = true;
1380  }
1381
1382  llvm::SmallVector<const char *, 16> Args;
1383  Args.push_back("<clang>"); // FIXME: Remove dummy argument.
1384  Args.insert(Args.end(), ArgBegin, ArgEnd);
1385
1386  // FIXME: Find a cleaner way to force the driver into restricted modes. We
1387  // also want to force it to use clang.
1388  Args.push_back("-fsyntax-only");
1389
1390  // FIXME: We shouldn't have to pass in the path info.
1391  driver::Driver TheDriver("clang", llvm::sys::getHostTriple(),
1392                           "a.out", false, false, *Diags);
1393
1394  // Don't check that inputs exist, they have been remapped.
1395  TheDriver.setCheckInputsExist(false);
1396
1397  llvm::OwningPtr<driver::Compilation> C(
1398    TheDriver.BuildCompilation(Args.size(), Args.data()));
1399
1400  // We expect to get back exactly one command job, if we didn't something
1401  // failed.
1402  const driver::JobList &Jobs = C->getJobs();
1403  if (Jobs.size() != 1 || !isa<driver::Command>(Jobs.begin())) {
1404    llvm::SmallString<256> Msg;
1405    llvm::raw_svector_ostream OS(Msg);
1406    C->PrintJob(OS, C->getJobs(), "; ", true);
1407    Diags->Report(diag::err_fe_expected_compiler_job) << OS.str();
1408    return 0;
1409  }
1410
1411  const driver::Command *Cmd = cast<driver::Command>(*Jobs.begin());
1412  if (llvm::StringRef(Cmd->getCreator().getName()) != "clang") {
1413    Diags->Report(diag::err_fe_expected_clang_command);
1414    return 0;
1415  }
1416
1417  const driver::ArgStringList &CCArgs = Cmd->getArguments();
1418  llvm::OwningPtr<CompilerInvocation> CI(new CompilerInvocation);
1419  CompilerInvocation::CreateFromArgs(*CI,
1420                                     const_cast<const char **>(CCArgs.data()),
1421                                     const_cast<const char **>(CCArgs.data()) +
1422                                     CCArgs.size(),
1423                                     *Diags);
1424
1425  // Override any files that need remapping
1426  for (unsigned I = 0; I != NumRemappedFiles; ++I)
1427    CI->getPreprocessorOpts().addRemappedFile(RemappedFiles[I].first,
1428                                              RemappedFiles[I].second);
1429
1430  // Override the resources path.
1431  CI->getHeaderSearchOpts().ResourceDir = ResourceFilesPath;
1432
1433  CI->getFrontendOpts().DisableFree = false;
1434  return LoadFromCompilerInvocation(CI.take(), Diags, OnlyLocalDecls,
1435                                    CaptureDiagnostics, PrecompilePreamble,
1436                                    CompleteTranslationUnit,
1437                                    CacheCodeCompletionResults);
1438}
1439
1440bool ASTUnit::Reparse(RemappedFile *RemappedFiles, unsigned NumRemappedFiles) {
1441  if (!Invocation.get())
1442    return true;
1443
1444  llvm::Timer *ReparsingTimer = 0;
1445  if (TimerGroup.get()) {
1446    ReparsingTimer = new llvm::Timer("Reparse", *TimerGroup);
1447    ReparsingTimer->startTimer();
1448    Timers.push_back(ReparsingTimer);
1449  }
1450
1451  // Remap files.
1452  PreprocessorOptions &PPOpts = Invocation->getPreprocessorOpts();
1453  for (PreprocessorOptions::remapped_file_buffer_iterator
1454         R = PPOpts.remapped_file_buffer_begin(),
1455         REnd = PPOpts.remapped_file_buffer_end();
1456       R != REnd;
1457       ++R) {
1458    delete R->second;
1459  }
1460  Invocation->getPreprocessorOpts().clearRemappedFiles();
1461  for (unsigned I = 0; I != NumRemappedFiles; ++I)
1462    Invocation->getPreprocessorOpts().addRemappedFile(RemappedFiles[I].first,
1463                                                      RemappedFiles[I].second);
1464
1465  // If we have a preamble file lying around, or if we might try to
1466  // build a precompiled preamble, do so now.
1467  llvm::MemoryBuffer *OverrideMainBuffer = 0;
1468  if (!PreambleFile.empty() || PreambleRebuildCounter > 0)
1469    OverrideMainBuffer = getMainBufferWithPrecompiledPreamble(*Invocation);
1470
1471  // Clear out the diagnostics state.
1472  if (!OverrideMainBuffer) {
1473    getDiagnostics().Reset();
1474    ProcessWarningOptions(getDiagnostics(), Invocation->getDiagnosticOpts());
1475  }
1476
1477  // Parse the sources
1478  bool Result = Parse(OverrideMainBuffer);
1479  if (ReparsingTimer)
1480    ReparsingTimer->stopTimer();
1481
1482  if (ShouldCacheCodeCompletionResults) {
1483    if (CacheCodeCompletionCoolDown > 0)
1484      --CacheCodeCompletionCoolDown;
1485    else if (top_level_size() != NumTopLevelDeclsAtLastCompletionCache)
1486      CacheCodeCompletionResults();
1487  }
1488
1489  return Result;
1490}
1491
1492//----------------------------------------------------------------------------//
1493// Code completion
1494//----------------------------------------------------------------------------//
1495
1496namespace {
1497  /// \brief Code completion consumer that combines the cached code-completion
1498  /// results from an ASTUnit with the code-completion results provided to it,
1499  /// then passes the result on to
1500  class AugmentedCodeCompleteConsumer : public CodeCompleteConsumer {
1501    unsigned NormalContexts;
1502    ASTUnit &AST;
1503    CodeCompleteConsumer &Next;
1504
1505  public:
1506    AugmentedCodeCompleteConsumer(ASTUnit &AST, CodeCompleteConsumer &Next,
1507                                  bool IncludeMacros, bool IncludeCodePatterns,
1508                                  bool IncludeGlobals)
1509      : CodeCompleteConsumer(IncludeMacros, IncludeCodePatterns, IncludeGlobals,
1510                             Next.isOutputBinary()), AST(AST), Next(Next)
1511    {
1512      // Compute the set of contexts in which we will look when we don't have
1513      // any information about the specific context.
1514      NormalContexts
1515        = (1 << (CodeCompletionContext::CCC_TopLevel - 1))
1516        | (1 << (CodeCompletionContext::CCC_ObjCInterface - 1))
1517        | (1 << (CodeCompletionContext::CCC_ObjCImplementation - 1))
1518        | (1 << (CodeCompletionContext::CCC_ObjCIvarList - 1))
1519        | (1 << (CodeCompletionContext::CCC_Statement - 1))
1520        | (1 << (CodeCompletionContext::CCC_Expression - 1))
1521        | (1 << (CodeCompletionContext::CCC_ObjCMessageReceiver - 1))
1522        | (1 << (CodeCompletionContext::CCC_MemberAccess - 1))
1523        | (1 << (CodeCompletionContext::CCC_ObjCProtocolName - 1))
1524        | (1 << (CodeCompletionContext::CCC_ParenthesizedExpression - 1))
1525        | (1 << (CodeCompletionContext::CCC_Recovery - 1));
1526
1527      if (AST.getASTContext().getLangOptions().CPlusPlus)
1528        NormalContexts |= (1 << (CodeCompletionContext::CCC_EnumTag - 1))
1529                    | (1 << (CodeCompletionContext::CCC_UnionTag - 1))
1530                    | (1 << (CodeCompletionContext::CCC_ClassOrStructTag - 1));
1531    }
1532
1533    virtual void ProcessCodeCompleteResults(Sema &S,
1534                                            CodeCompletionContext Context,
1535                                            CodeCompletionResult *Results,
1536                                            unsigned NumResults);
1537
1538    virtual void ProcessOverloadCandidates(Sema &S, unsigned CurrentArg,
1539                                           OverloadCandidate *Candidates,
1540                                           unsigned NumCandidates) {
1541      Next.ProcessOverloadCandidates(S, CurrentArg, Candidates, NumCandidates);
1542    }
1543  };
1544}
1545
1546/// \brief Helper function that computes which global names are hidden by the
1547/// local code-completion results.
1548void CalculateHiddenNames(const CodeCompletionContext &Context,
1549                          CodeCompletionResult *Results,
1550                          unsigned NumResults,
1551                          ASTContext &Ctx,
1552                          llvm::StringSet<> &HiddenNames) {
1553  bool OnlyTagNames = false;
1554  switch (Context.getKind()) {
1555  case CodeCompletionContext::CCC_Recovery:
1556  case CodeCompletionContext::CCC_TopLevel:
1557  case CodeCompletionContext::CCC_ObjCInterface:
1558  case CodeCompletionContext::CCC_ObjCImplementation:
1559  case CodeCompletionContext::CCC_ObjCIvarList:
1560  case CodeCompletionContext::CCC_ClassStructUnion:
1561  case CodeCompletionContext::CCC_Statement:
1562  case CodeCompletionContext::CCC_Expression:
1563  case CodeCompletionContext::CCC_ObjCMessageReceiver:
1564  case CodeCompletionContext::CCC_MemberAccess:
1565  case CodeCompletionContext::CCC_Namespace:
1566  case CodeCompletionContext::CCC_Type:
1567  case CodeCompletionContext::CCC_Name:
1568  case CodeCompletionContext::CCC_PotentiallyQualifiedName:
1569  case CodeCompletionContext::CCC_ParenthesizedExpression:
1570    break;
1571
1572  case CodeCompletionContext::CCC_EnumTag:
1573  case CodeCompletionContext::CCC_UnionTag:
1574  case CodeCompletionContext::CCC_ClassOrStructTag:
1575    OnlyTagNames = true;
1576    break;
1577
1578  case CodeCompletionContext::CCC_ObjCProtocolName:
1579  case CodeCompletionContext::CCC_MacroName:
1580  case CodeCompletionContext::CCC_MacroNameUse:
1581  case CodeCompletionContext::CCC_PreprocessorExpression:
1582  case CodeCompletionContext::CCC_PreprocessorDirective:
1583  case CodeCompletionContext::CCC_NaturalLanguage:
1584  case CodeCompletionContext::CCC_SelectorName:
1585  case CodeCompletionContext::CCC_TypeQualifiers:
1586  case CodeCompletionContext::CCC_Other:
1587    // We're looking for nothing, or we're looking for names that cannot
1588    // be hidden.
1589    return;
1590  }
1591
1592  typedef CodeCompletionResult Result;
1593  for (unsigned I = 0; I != NumResults; ++I) {
1594    if (Results[I].Kind != Result::RK_Declaration)
1595      continue;
1596
1597    unsigned IDNS
1598      = Results[I].Declaration->getUnderlyingDecl()->getIdentifierNamespace();
1599
1600    bool Hiding = false;
1601    if (OnlyTagNames)
1602      Hiding = (IDNS & Decl::IDNS_Tag);
1603    else {
1604      unsigned HiddenIDNS = (Decl::IDNS_Type | Decl::IDNS_Member |
1605                             Decl::IDNS_Namespace | Decl::IDNS_Ordinary |
1606                             Decl::IDNS_NonMemberOperator);
1607      if (Ctx.getLangOptions().CPlusPlus)
1608        HiddenIDNS |= Decl::IDNS_Tag;
1609      Hiding = (IDNS & HiddenIDNS);
1610    }
1611
1612    if (!Hiding)
1613      continue;
1614
1615    DeclarationName Name = Results[I].Declaration->getDeclName();
1616    if (IdentifierInfo *Identifier = Name.getAsIdentifierInfo())
1617      HiddenNames.insert(Identifier->getName());
1618    else
1619      HiddenNames.insert(Name.getAsString());
1620  }
1621}
1622
1623
1624void AugmentedCodeCompleteConsumer::ProcessCodeCompleteResults(Sema &S,
1625                                            CodeCompletionContext Context,
1626                                            CodeCompletionResult *Results,
1627                                            unsigned NumResults) {
1628  // Merge the results we were given with the results we cached.
1629  bool AddedResult = false;
1630  unsigned InContexts
1631    = (Context.getKind() == CodeCompletionContext::CCC_Recovery? NormalContexts
1632                                            : (1 << (Context.getKind() - 1)));
1633
1634  // Contains the set of names that are hidden by "local" completion results.
1635  llvm::StringSet<> HiddenNames;
1636  llvm::SmallVector<CodeCompletionString *, 4> StringsToDestroy;
1637  typedef CodeCompletionResult Result;
1638  llvm::SmallVector<Result, 8> AllResults;
1639  for (ASTUnit::cached_completion_iterator
1640            C = AST.cached_completion_begin(),
1641         CEnd = AST.cached_completion_end();
1642       C != CEnd; ++C) {
1643    // If the context we are in matches any of the contexts we are
1644    // interested in, we'll add this result.
1645    if ((C->ShowInContexts & InContexts) == 0)
1646      continue;
1647
1648    // If we haven't added any results previously, do so now.
1649    if (!AddedResult) {
1650      CalculateHiddenNames(Context, Results, NumResults, S.Context,
1651                           HiddenNames);
1652      AllResults.insert(AllResults.end(), Results, Results + NumResults);
1653      AddedResult = true;
1654    }
1655
1656    // Determine whether this global completion result is hidden by a local
1657    // completion result. If so, skip it.
1658    if (C->Kind != CXCursor_MacroDefinition &&
1659        HiddenNames.count(C->Completion->getTypedText()))
1660      continue;
1661
1662    // Adjust priority based on similar type classes.
1663    unsigned Priority = C->Priority;
1664    CXCursorKind CursorKind = C->Kind;
1665    CodeCompletionString *Completion = C->Completion;
1666    if (!Context.getPreferredType().isNull()) {
1667      if (C->Kind == CXCursor_MacroDefinition) {
1668        Priority = getMacroUsagePriority(C->Completion->getTypedText(),
1669                                         S.getLangOptions(),
1670                               Context.getPreferredType()->isAnyPointerType());
1671      } else if (C->Type) {
1672        CanQualType Expected
1673          = S.Context.getCanonicalType(
1674                               Context.getPreferredType().getUnqualifiedType());
1675        SimplifiedTypeClass ExpectedSTC = getSimplifiedTypeClass(Expected);
1676        if (ExpectedSTC == C->TypeClass) {
1677          // We know this type is similar; check for an exact match.
1678          llvm::StringMap<unsigned> &CachedCompletionTypes
1679            = AST.getCachedCompletionTypes();
1680          llvm::StringMap<unsigned>::iterator Pos
1681            = CachedCompletionTypes.find(QualType(Expected).getAsString());
1682          if (Pos != CachedCompletionTypes.end() && Pos->second == C->Type)
1683            Priority /= CCF_ExactTypeMatch;
1684          else
1685            Priority /= CCF_SimilarTypeMatch;
1686        }
1687      }
1688    }
1689
1690    // Adjust the completion string, if required.
1691    if (C->Kind == CXCursor_MacroDefinition &&
1692        Context.getKind() == CodeCompletionContext::CCC_MacroNameUse) {
1693      // Create a new code-completion string that just contains the
1694      // macro name, without its arguments.
1695      Completion = new CodeCompletionString;
1696      Completion->AddTypedTextChunk(C->Completion->getTypedText());
1697      StringsToDestroy.push_back(Completion);
1698      CursorKind = CXCursor_NotImplemented;
1699      Priority = CCP_CodePattern;
1700    }
1701
1702    AllResults.push_back(Result(Completion, Priority, CursorKind,
1703                                C->Availability));
1704  }
1705
1706  // If we did not add any cached completion results, just forward the
1707  // results we were given to the next consumer.
1708  if (!AddedResult) {
1709    Next.ProcessCodeCompleteResults(S, Context, Results, NumResults);
1710    return;
1711  }
1712
1713  Next.ProcessCodeCompleteResults(S, Context, AllResults.data(),
1714                                  AllResults.size());
1715
1716  for (unsigned I = 0, N = StringsToDestroy.size(); I != N; ++I)
1717    delete StringsToDestroy[I];
1718}
1719
1720
1721
1722void ASTUnit::CodeComplete(llvm::StringRef File, unsigned Line, unsigned Column,
1723                           RemappedFile *RemappedFiles,
1724                           unsigned NumRemappedFiles,
1725                           bool IncludeMacros,
1726                           bool IncludeCodePatterns,
1727                           CodeCompleteConsumer &Consumer,
1728                           Diagnostic &Diag, LangOptions &LangOpts,
1729                           SourceManager &SourceMgr, FileManager &FileMgr,
1730                   llvm::SmallVectorImpl<StoredDiagnostic> &StoredDiagnostics,
1731             llvm::SmallVectorImpl<const llvm::MemoryBuffer *> &OwnedBuffers) {
1732  if (!Invocation.get())
1733    return;
1734
1735  llvm::Timer *CompletionTimer = 0;
1736  if (TimerGroup.get()) {
1737    llvm::SmallString<128> TimerName;
1738    llvm::raw_svector_ostream TimerNameOut(TimerName);
1739    TimerNameOut << "Code completion @ " << File << ":" << Line << ":"
1740                 << Column;
1741    CompletionTimer = new llvm::Timer(TimerNameOut.str(), *TimerGroup);
1742    CompletionTimer->startTimer();
1743    Timers.push_back(CompletionTimer);
1744  }
1745
1746  CompilerInvocation CCInvocation(*Invocation);
1747  FrontendOptions &FrontendOpts = CCInvocation.getFrontendOpts();
1748  PreprocessorOptions &PreprocessorOpts = CCInvocation.getPreprocessorOpts();
1749
1750  FrontendOpts.ShowMacrosInCodeCompletion
1751    = IncludeMacros && CachedCompletionResults.empty();
1752  FrontendOpts.ShowCodePatternsInCodeCompletion = IncludeCodePatterns;
1753  FrontendOpts.ShowGlobalSymbolsInCodeCompletion
1754    = CachedCompletionResults.empty();
1755  FrontendOpts.CodeCompletionAt.FileName = File;
1756  FrontendOpts.CodeCompletionAt.Line = Line;
1757  FrontendOpts.CodeCompletionAt.Column = Column;
1758
1759  // Set the language options appropriately.
1760  LangOpts = CCInvocation.getLangOpts();
1761
1762  CompilerInstance Clang;
1763  Clang.setInvocation(&CCInvocation);
1764  OriginalSourceFile = Clang.getFrontendOpts().Inputs[0].second;
1765
1766  // Set up diagnostics, capturing any diagnostics produced.
1767  Clang.setDiagnostics(&Diag);
1768  ProcessWarningOptions(Diag, CCInvocation.getDiagnosticOpts());
1769  CaptureDroppedDiagnostics Capture(true,
1770                                    Clang.getDiagnostics(),
1771                                    StoredDiagnostics);
1772
1773  // Create the target instance.
1774  Clang.setTarget(TargetInfo::CreateTargetInfo(Clang.getDiagnostics(),
1775                                               Clang.getTargetOpts()));
1776  if (!Clang.hasTarget()) {
1777    Clang.takeInvocation();
1778    return;
1779  }
1780
1781  // Inform the target of the language options.
1782  //
1783  // FIXME: We shouldn't need to do this, the target should be immutable once
1784  // created. This complexity should be lifted elsewhere.
1785  Clang.getTarget().setForcedLangOptions(Clang.getLangOpts());
1786
1787  assert(Clang.getFrontendOpts().Inputs.size() == 1 &&
1788         "Invocation must have exactly one source file!");
1789  assert(Clang.getFrontendOpts().Inputs[0].first != IK_AST &&
1790         "FIXME: AST inputs not yet supported here!");
1791  assert(Clang.getFrontendOpts().Inputs[0].first != IK_LLVM_IR &&
1792         "IR inputs not support here!");
1793
1794
1795  // Use the source and file managers that we were given.
1796  Clang.setFileManager(&FileMgr);
1797  Clang.setSourceManager(&SourceMgr);
1798
1799  // Remap files.
1800  PreprocessorOpts.clearRemappedFiles();
1801  PreprocessorOpts.RetainRemappedFileBuffers = true;
1802  for (unsigned I = 0; I != NumRemappedFiles; ++I) {
1803    PreprocessorOpts.addRemappedFile(RemappedFiles[I].first,
1804                                     RemappedFiles[I].second);
1805    OwnedBuffers.push_back(RemappedFiles[I].second);
1806  }
1807
1808  // Use the code completion consumer we were given, but adding any cached
1809  // code-completion results.
1810  AugmentedCodeCompleteConsumer
1811  AugmentedConsumer(*this, Consumer, FrontendOpts.ShowMacrosInCodeCompletion,
1812                    FrontendOpts.ShowCodePatternsInCodeCompletion,
1813                    FrontendOpts.ShowGlobalSymbolsInCodeCompletion);
1814  Clang.setCodeCompletionConsumer(&AugmentedConsumer);
1815
1816  // If we have a precompiled preamble, try to use it. We only allow
1817  // the use of the precompiled preamble if we're if the completion
1818  // point is within the main file, after the end of the precompiled
1819  // preamble.
1820  llvm::MemoryBuffer *OverrideMainBuffer = 0;
1821  if (!PreambleFile.empty()) {
1822    using llvm::sys::FileStatus;
1823    llvm::sys::PathWithStatus CompleteFilePath(File);
1824    llvm::sys::PathWithStatus MainPath(OriginalSourceFile);
1825    if (const FileStatus *CompleteFileStatus = CompleteFilePath.getFileStatus())
1826      if (const FileStatus *MainStatus = MainPath.getFileStatus())
1827        if (CompleteFileStatus->getUniqueID() == MainStatus->getUniqueID())
1828          OverrideMainBuffer
1829            = getMainBufferWithPrecompiledPreamble(CCInvocation, false,
1830                                                   Line - 1);
1831  }
1832
1833  // If the main file has been overridden due to the use of a preamble,
1834  // make that override happen and introduce the preamble.
1835  if (OverrideMainBuffer) {
1836    PreprocessorOpts.addRemappedFile(OriginalSourceFile, OverrideMainBuffer);
1837    PreprocessorOpts.PrecompiledPreambleBytes.first = Preamble.size();
1838    PreprocessorOpts.PrecompiledPreambleBytes.second
1839                                                    = PreambleEndsAtStartOfLine;
1840    PreprocessorOpts.ImplicitPCHInclude = PreambleFile;
1841    PreprocessorOpts.DisablePCHValidation = true;
1842
1843    // The stored diagnostics have the old source manager. Copy them
1844    // to our output set of stored diagnostics, updating the source
1845    // manager to the one we were given.
1846    for (unsigned I = 0, N = this->StoredDiagnostics.size(); I != N; ++I) {
1847      StoredDiagnostics.push_back(this->StoredDiagnostics[I]);
1848      FullSourceLoc Loc(StoredDiagnostics[I].getLocation(), SourceMgr);
1849      StoredDiagnostics[I].setLocation(Loc);
1850    }
1851
1852    OwnedBuffers.push_back(OverrideMainBuffer);
1853  } else {
1854    PreprocessorOpts.PrecompiledPreambleBytes.first = 0;
1855    PreprocessorOpts.PrecompiledPreambleBytes.second = false;
1856  }
1857
1858  llvm::OwningPtr<SyntaxOnlyAction> Act;
1859  Act.reset(new SyntaxOnlyAction);
1860  if (Act->BeginSourceFile(Clang, Clang.getFrontendOpts().Inputs[0].second,
1861                           Clang.getFrontendOpts().Inputs[0].first)) {
1862    Act->Execute();
1863    Act->EndSourceFile();
1864  }
1865
1866  if (CompletionTimer)
1867    CompletionTimer->stopTimer();
1868
1869  // Steal back our resources.
1870  Clang.takeFileManager();
1871  Clang.takeSourceManager();
1872  Clang.takeInvocation();
1873  Clang.takeCodeCompletionConsumer();
1874}
1875
1876bool ASTUnit::Save(llvm::StringRef File) {
1877  if (getDiagnostics().hasErrorOccurred())
1878    return true;
1879
1880  // FIXME: Can we somehow regenerate the stat cache here, or do we need to
1881  // unconditionally create a stat cache when we parse the file?
1882  std::string ErrorInfo;
1883  llvm::raw_fd_ostream Out(File.str().c_str(), ErrorInfo,
1884                           llvm::raw_fd_ostream::F_Binary);
1885  if (!ErrorInfo.empty() || Out.has_error())
1886    return true;
1887
1888  std::vector<unsigned char> Buffer;
1889  llvm::BitstreamWriter Stream(Buffer);
1890  ASTWriter Writer(Stream);
1891  Writer.WriteAST(getSema(), 0, 0);
1892
1893  // Write the generated bitstream to "Out".
1894  if (!Buffer.empty())
1895    Out.write((char *)&Buffer.front(), Buffer.size());
1896  Out.close();
1897  return Out.has_error();
1898}
1899