C++ ASTContext::getExternalSource方法代码示例

void FunctionDecl::Destroy(ASTContext& C) {
  if (Body && Body.isOffset())
    Body.get(C.getExternalSource())->Destroy(C);

  for (param_iterator I=param_begin(), E=param_end(); I!=E; ++I)
    (*I)->Destroy(C);

  C.Deallocate(ParamInfo);

  Decl::Destroy(C);
}

/// ParseAST - Parse the entire file specified, notifying the ASTConsumer as
/// the file is parsed.  This inserts the parsed decls into the translation unit
/// held by Ctx.
///
void clang::ParseAST(Preprocessor &PP, ASTConsumer *Consumer,
                     ASTContext &Ctx, bool PrintStats,
                     bool CompleteTranslationUnit) {
  // Collect global stats on Decls/Stmts (until we have a module streamer).
  if (PrintStats) {
    Decl::CollectingStats(true);
    Stmt::CollectingStats(true);
  }

  Sema S(PP, Ctx, *Consumer, CompleteTranslationUnit);
  Parser P(PP, S);
  PP.EnterMainSourceFile();
    
  // Initialize the parser.
  P.Initialize();
  
  Consumer->Initialize(Ctx);
  
  if (SemaConsumer *SC = dyn_cast<SemaConsumer>(Consumer))
    SC->InitializeSema(S);

  if (ExternalASTSource *External = Ctx.getExternalSource()) {
    if (ExternalSemaSource *ExternalSema = 
          dyn_cast<ExternalSemaSource>(External))
      ExternalSema->InitializeSema(S);

    External->StartTranslationUnit(Consumer);
  }

  Parser::DeclGroupPtrTy ADecl;
  
  while (!P.ParseTopLevelDecl(ADecl)) {  // Not end of file.
    // If we got a null return and something *was* parsed, ignore it.  This
    // is due to a top-level semicolon, an action override, or a parse error
    // skipping something.
    if (ADecl)
      Consumer->HandleTopLevelDecl(ADecl.getAsVal<DeclGroupRef>());
  };
  
  Consumer->HandleTranslationUnit(Ctx);

  if (PrintStats) {
    fprintf(stderr, "\nSTATISTICS:\n");
    P.getActions().PrintStats();
    Ctx.PrintStats();
    Decl::PrintStats();
    Stmt::PrintStats();
    Consumer->PrintStats();
    
    Decl::CollectingStats(false);
    Stmt::CollectingStats(false);
  }
}

void StoredDeclsList::materializeDecls(ASTContext &Context) {
  if (isNull())
    return;

  switch ((DataKind)(Data & 0x03)) {
  case DK_Decl:
  case DK_Decl_Vector:
    break;

  case DK_DeclID: {
    // Resolve this declaration ID to an actual declaration by
    // querying the external AST source.
    unsigned DeclID = Data >> 2;

    ExternalASTSource *Source = Context.getExternalSource();
    assert(Source && "No external AST source available!");

    Data = reinterpret_cast<uintptr_t>(Source->GetDecl(DeclID));
    break;
  }

  case DK_ID_Vector: {
    // We have a vector of declaration IDs. Resolve all of them to
    // actual declarations.
    VectorTy &Vector = *getAsVector();
    ExternalASTSource *Source = Context.getExternalSource();
    assert(Source && "No external AST source available!");

    for (unsigned I = 0, N = Vector.size(); I != N; ++I)
      Vector[I] = reinterpret_cast<uintptr_t>(Source->GetDecl(Vector[I]));

    Data = (Data & ~0x03) | DK_Decl_Vector;
    break;
  }
  }
}

uint32_t ExternalASTSource::incrementGeneration(ASTContext &C) {
  uint32_t OldGeneration = CurrentGeneration;

  // Make sure the generation of the topmost external source for the context is
  // incremented. That might not be us.
  auto *P = C.getExternalSource();
  if (P && P != this)
    CurrentGeneration = P->incrementGeneration(C);
  else {
    // FIXME: Only bump the generation counter if the current generation number
    // has been observed?
    if (!++CurrentGeneration)
      llvm::report_fatal_error("generation counter overflowed", false);
  }

  return OldGeneration;
}

void FunctionDecl::Destroy(ASTContext& C) {
  if (Body && Body.isOffset())
    Body.get(C.getExternalSource())->Destroy(C);

  for (param_iterator I=param_begin(), E=param_end(); I!=E; ++I)
    (*I)->Destroy(C);

  FunctionTemplateSpecializationInfo *FTSInfo
    = TemplateOrSpecialization.dyn_cast<FunctionTemplateSpecializationInfo*>();
  if (FTSInfo)
    C.Deallocate(FTSInfo);
  
  MemberSpecializationInfo *MSInfo
    = TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo*>();
  if (MSInfo)
    C.Deallocate(MSInfo);
  
  C.Deallocate(ParamInfo);

  Decl::Destroy(C);
}

/// ParseAST - Parse the entire file specified, notifying the ASTConsumer as
/// the file is parsed.  This inserts the parsed decls into the translation unit
/// held by Ctx.
///
void clang::ParseAST(Preprocessor &PP, ASTConsumer *Consumer,
                     ASTContext &Ctx, bool PrintStats,
                     bool CompleteTranslationUnit,
                     CodeCompleteConsumer *CompletionConsumer) {
  // Collect global stats on Decls/Stmts (until we have a module streamer).
  if (PrintStats) {
    Decl::CollectingStats(true);
    Stmt::CollectingStats(true);
  }

  Sema S(PP, Ctx, *Consumer, CompleteTranslationUnit, CompletionConsumer);
  Parser P(PP, S);
  PP.EnterMainSourceFile();

  // Initialize the parser.
  P.Initialize();

  Consumer->Initialize(Ctx);

  if (SemaConsumer *SC = dyn_cast<SemaConsumer>(Consumer))
    SC->InitializeSema(S);

  if (ExternalASTSource *External = Ctx.getExternalSource()) {
    if (ExternalSemaSource *ExternalSema =
          dyn_cast<ExternalSemaSource>(External))
      ExternalSema->InitializeSema(S);

    External->StartTranslationUnit(Consumer);
  }

  Parser::DeclGroupPtrTy ADecl;

  while (!P.ParseTopLevelDecl(ADecl)) {  // Not end of file.
    // If we got a null return and something *was* parsed, ignore it.  This
    // is due to a top-level semicolon, an action override, or a parse error
    // skipping something.
    if (ADecl)
      Consumer->HandleTopLevelDecl(ADecl.getAsVal<DeclGroupRef>());
  };
  // Check for any pending objective-c implementation decl.
  while ((ADecl = P.FinishPendingObjCActions()))
    Consumer->HandleTopLevelDecl(ADecl.getAsVal<DeclGroupRef>());

  // Process any TopLevelDecls generated by #pragma weak.
  for (llvm::SmallVector<Decl*,2>::iterator
        I = S.WeakTopLevelDecls().begin(),
        E = S.WeakTopLevelDecls().end(); I != E; ++I)
    Consumer->HandleTopLevelDecl(DeclGroupRef(*I));

  // Dump record layouts, if requested.
  if (PP.getLangOptions().DumpRecordLayouts)
    DumpRecordLayouts(Ctx);

  Consumer->HandleTranslationUnit(Ctx);

  if (ExternalSemaSource *ESS =
        dyn_cast_or_null<ExternalSemaSource>(Ctx.getExternalSource()))
    ESS->ForgetSema();

  if (SemaConsumer *SC = dyn_cast<SemaConsumer>(Consumer))
    SC->ForgetSema();

  if (PrintStats) {
    fprintf(stderr, "\nSTATISTICS:\n");
    P.getActions().PrintStats();
    Ctx.PrintStats();
    Decl::PrintStats();
    Stmt::PrintStats();
    Consumer->PrintStats();
  }
}