contrib/llvm/tools/clang/lib/AST/ExternalASTSource.cpp

   1 //===- ExternalASTSource.cpp - Abstract External AST Interface --*- C++ -*-===//
   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 //  This file provides the default implementation of the ExternalASTSource
  11 //  interface, which enables construction of AST nodes from some external
  12 //  source.
  13 //
  14 //===----------------------------------------------------------------------===//
  15
  16 #include "clang/AST/ExternalASTSource.h"
  17 #include "clang/AST/ASTContext.h"
  18 #include "clang/AST/DeclarationName.h"
  19 #include "llvm/Support/ErrorHandling.h"
  20
  21 using namespace clang;
  22
  23 ExternalASTSource::~ExternalASTSource() { }
  24
  25 llvm::Optional<ExternalASTSource::ASTSourceDescriptor>
  26 ExternalASTSource::getSourceDescriptor(unsigned ID) {
  27   return None;
  28 }
  29
  30 ExternalASTSource::ASTSourceDescriptor
  31 ExternalASTSource::getSourceDescriptor(const Module &M) {
  32   return ASTSourceDescriptor();
  33 }
  34
  35 void ExternalASTSource::FindFileRegionDecls(FileID File, unsigned Offset,
  36                                             unsigned Length,
  37                                             SmallVectorImpl<Decl *> &Decls) {}
  38
  39 void ExternalASTSource::CompleteRedeclChain(const Decl *D) {}
  40
  41 void ExternalASTSource::CompleteType(TagDecl *Tag) {}
  42
  43 void ExternalASTSource::CompleteType(ObjCInterfaceDecl *Class) {}
  44
  45 void ExternalASTSource::ReadComments() {}
  46
  47 void ExternalASTSource::StartedDeserializing() {}
  48
  49 void ExternalASTSource::FinishedDeserializing() {}
  50
  51 void ExternalASTSource::StartTranslationUnit(ASTConsumer *Consumer) {}
  52
  53 void ExternalASTSource::PrintStats() { }
  54
  55 bool ExternalASTSource::layoutRecordType(
  56     const RecordDecl *Record, uint64_t &Size, uint64_t &Alignment,
  57     llvm::DenseMap<const FieldDecl *, uint64_t> &FieldOffsets,
  58     llvm::DenseMap<const CXXRecordDecl *, CharUnits> &BaseOffsets,
  59     llvm::DenseMap<const CXXRecordDecl *, CharUnits> &VirtualBaseOffsets) {
  60   return false;
  61 }
  62
  63 Decl *ExternalASTSource::GetExternalDecl(uint32_t ID) {
  64   return nullptr;
  65 }
  66
  67 Selector ExternalASTSource::GetExternalSelector(uint32_t ID) {
  68   return Selector();
  69 }
  70
  71 uint32_t ExternalASTSource::GetNumExternalSelectors() {
  72    return 0;
  73 }
  74
  75 Stmt *ExternalASTSource::GetExternalDeclStmt(uint64_t Offset) {
  76   return nullptr;
  77 }
  78
  79 CXXCtorInitializer **
  80 ExternalASTSource::GetExternalCXXCtorInitializers(uint64_t Offset) {
  81   return nullptr;
  82 }
  83
  84 CXXBaseSpecifier *
  85 ExternalASTSource::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
  86   return nullptr;
  87 }
  88
  89 bool
  90 ExternalASTSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
  91                                                   DeclarationName Name) {
  92   return false;
  93 }
  94
  95 void ExternalASTSource::completeVisibleDeclsMap(const DeclContext *DC) {
  96 }
  97
  98 ExternalLoadResult
  99 ExternalASTSource::FindExternalLexicalDecls(const DeclContext *DC,
 100                                             bool (*isKindWeWant)(Decl::Kind),
 101                                          SmallVectorImpl<Decl*> &Result) {
 102   return ELR_AlreadyLoaded;
 103 }
 104
 105 void ExternalASTSource::getMemoryBufferSizes(MemoryBufferSizes &sizes) const { }
 106
 107 uint32_t ExternalASTSource::incrementGeneration(ASTContext &C) {
 108   uint32_t OldGeneration = CurrentGeneration;
 109
 110   // Make sure the generation of the topmost external source for the context is
 111   // incremented. That might not be us.
 112   auto *P = C.getExternalSource();
 113   if (P && P != this)
 114     CurrentGeneration = P->incrementGeneration(C);
 115   else {
 116     // FIXME: Only bump the generation counter if the current generation number
 117     // has been observed?
 118     if (!++CurrentGeneration)
 119       llvm::report_fatal_error("generation counter overflowed", false);
 120   }
 121
 122   return OldGeneration;
 123 }