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

   1 //===- ExternalASTSource.cpp - Abstract External AST Interface ------------===//
   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 "clang/Basic/IdentifierTable.h"
  20 #include "clang/Basic/LLVM.h"
  21 #include "clang/Basic/Module.h"
  22 #include "llvm/ADT/None.h"
  23 #include "llvm/Support/ErrorHandling.h"
  24 #include <cstdint>
  25
  26 using namespace clang;
  27
  28 ExternalASTSource::~ExternalASTSource() = default;
  29
  30 llvm::Optional<ExternalASTSource::ASTSourceDescriptor>
  31 ExternalASTSource::getSourceDescriptor(unsigned ID) {
  32   return None;
  33 }
  34
  35 ExternalASTSource::ExtKind
  36 ExternalASTSource::hasExternalDefinitions(const Decl *D) {
  37   return EK_ReplyHazy;
  38 }
  39
  40 ExternalASTSource::ASTSourceDescriptor::ASTSourceDescriptor(const Module &M)
  41   : Signature(M.Signature), ClangModule(&M) {
  42   if (M.Directory)
  43     Path = M.Directory->getName();
  44   if (auto *File = M.getASTFile())
  45     ASTFile = File->getName();
  46 }
  47
  48 std::string ExternalASTSource::ASTSourceDescriptor::getModuleName() const {
  49   if (ClangModule)
  50     return ClangModule->Name;
  51   else
  52     return PCHModuleName;
  53 }
  54
  55 void ExternalASTSource::FindFileRegionDecls(FileID File, unsigned Offset,
  56                                             unsigned Length,
  57                                             SmallVectorImpl<Decl *> &Decls) {}
  58
  59 void ExternalASTSource::CompleteRedeclChain(const Decl *D) {}
  60
  61 void ExternalASTSource::CompleteType(TagDecl *Tag) {}
  62
  63 void ExternalASTSource::CompleteType(ObjCInterfaceDecl *Class) {}
  64
  65 void ExternalASTSource::ReadComments() {}
  66
  67 void ExternalASTSource::StartedDeserializing() {}
  68
  69 void ExternalASTSource::FinishedDeserializing() {}
  70
  71 void ExternalASTSource::StartTranslationUnit(ASTConsumer *Consumer) {}
  72
  73 void ExternalASTSource::PrintStats() {}
  74
  75 bool ExternalASTSource::layoutRecordType(
  76     const RecordDecl *Record, uint64_t &Size, uint64_t &Alignment,
  77     llvm::DenseMap<const FieldDecl *, uint64_t> &FieldOffsets,
  78     llvm::DenseMap<const CXXRecordDecl *, CharUnits> &BaseOffsets,
  79     llvm::DenseMap<const CXXRecordDecl *, CharUnits> &VirtualBaseOffsets) {
  80   return false;
  81 }
  82
  83 Decl *ExternalASTSource::GetExternalDecl(uint32_t ID) {
  84   return nullptr;
  85 }
  86
  87 Selector ExternalASTSource::GetExternalSelector(uint32_t ID) {
  88   return Selector();
  89 }
  90
  91 uint32_t ExternalASTSource::GetNumExternalSelectors() {
  92    return 0;
  93 }
  94
  95 Stmt *ExternalASTSource::GetExternalDeclStmt(uint64_t Offset) {
  96   return nullptr;
  97 }
  98
  99 CXXCtorInitializer **
 100 ExternalASTSource::GetExternalCXXCtorInitializers(uint64_t Offset) {
 101   return nullptr;
 102 }
 103
 104 CXXBaseSpecifier *
 105 ExternalASTSource::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
 106   return nullptr;
 107 }
 108
 109 bool
 110 ExternalASTSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
 111                                                   DeclarationName Name) {
 112   return false;
 113 }
 114
 115 void ExternalASTSource::completeVisibleDeclsMap(const DeclContext *DC) {}
 116
 117 void ExternalASTSource::FindExternalLexicalDecls(
 118     const DeclContext *DC, llvm::function_ref<bool(Decl::Kind)> IsKindWeWant,
 119     SmallVectorImpl<Decl *> &Result) {}
 120
 121 void ExternalASTSource::getMemoryBufferSizes(MemoryBufferSizes &sizes) const {}
 122
 123 uint32_t ExternalASTSource::incrementGeneration(ASTContext &C) {
 124   uint32_t OldGeneration = CurrentGeneration;
 125
 126   // Make sure the generation of the topmost external source for the context is
 127   // incremented. That might not be us.
 128   auto *P = C.getExternalSource();
 129   if (P && P != this)
 130     CurrentGeneration = P->incrementGeneration(C);
 131   else {
 132     // FIXME: Only bump the generation counter if the current generation number
 133     // has been observed?
 134     if (!++CurrentGeneration)
 135       llvm::report_fatal_error("generation counter overflowed", false);
 136   }
 137
 138   return OldGeneration;
 139 }