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

   1 //===- ExternalASTSource.cpp - Abstract External AST Interface ------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 //  This file provides the default implementation of the ExternalASTSource
  10 //  interface, which enables construction of AST nodes from some external
  11 //  source.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "clang/AST/ExternalASTSource.h"
  16 #include "clang/AST/ASTContext.h"
  17 #include "clang/AST/DeclarationName.h"
  18 #include "clang/Basic/IdentifierTable.h"
  19 #include "clang/Basic/LLVM.h"
  20 #include "clang/Basic/Module.h"
  21 #include "llvm/ADT/None.h"
  22 #include "llvm/Support/ErrorHandling.h"
  23 #include <cstdint>
  24
  25 using namespace clang;
  26
  27 ExternalASTSource::~ExternalASTSource() = default;
  28
  29 llvm::Optional<ExternalASTSource::ASTSourceDescriptor>
  30 ExternalASTSource::getSourceDescriptor(unsigned ID) {
  31   return None;
  32 }
  33
  34 ExternalASTSource::ExtKind
  35 ExternalASTSource::hasExternalDefinitions(const Decl *D) {
  36   return EK_ReplyHazy;
  37 }
  38
  39 ExternalASTSource::ASTSourceDescriptor::ASTSourceDescriptor(const Module &M)
  40   : Signature(M.Signature), ClangModule(&M) {
  41   if (M.Directory)
  42     Path = M.Directory->getName();
  43   if (auto *File = M.getASTFile())
  44     ASTFile = File->getName();
  45 }
  46
  47 std::string ExternalASTSource::ASTSourceDescriptor::getModuleName() const {
  48   if (ClangModule)
  49     return ClangModule->Name;
  50   else
  51     return PCHModuleName;
  52 }
  53
  54 void ExternalASTSource::FindFileRegionDecls(FileID File, unsigned Offset,
  55                                             unsigned Length,
  56                                             SmallVectorImpl<Decl *> &Decls) {}
  57
  58 void ExternalASTSource::CompleteRedeclChain(const Decl *D) {}
  59
  60 void ExternalASTSource::CompleteType(TagDecl *Tag) {}
  61
  62 void ExternalASTSource::CompleteType(ObjCInterfaceDecl *Class) {}
  63
  64 void ExternalASTSource::ReadComments() {}
  65
  66 void ExternalASTSource::StartedDeserializing() {}
  67
  68 void ExternalASTSource::FinishedDeserializing() {}
  69
  70 void ExternalASTSource::StartTranslationUnit(ASTConsumer *Consumer) {}
  71
  72 void ExternalASTSource::PrintStats() {}
  73
  74 bool ExternalASTSource::layoutRecordType(
  75     const RecordDecl *Record, uint64_t &Size, uint64_t &Alignment,
  76     llvm::DenseMap<const FieldDecl *, uint64_t> &FieldOffsets,
  77     llvm::DenseMap<const CXXRecordDecl *, CharUnits> &BaseOffsets,
  78     llvm::DenseMap<const CXXRecordDecl *, CharUnits> &VirtualBaseOffsets) {
  79   return false;
  80 }
  81
  82 Decl *ExternalASTSource::GetExternalDecl(uint32_t ID) {
  83   return nullptr;
  84 }
  85
  86 Selector ExternalASTSource::GetExternalSelector(uint32_t ID) {
  87   return Selector();
  88 }
  89
  90 uint32_t ExternalASTSource::GetNumExternalSelectors() {
  91    return 0;
  92 }
  93
  94 Stmt *ExternalASTSource::GetExternalDeclStmt(uint64_t Offset) {
  95   return nullptr;
  96 }
  97
  98 CXXCtorInitializer **
  99 ExternalASTSource::GetExternalCXXCtorInitializers(uint64_t Offset) {
 100   return nullptr;
 101 }
 102
 103 CXXBaseSpecifier *
 104 ExternalASTSource::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
 105   return nullptr;
 106 }
 107
 108 bool
 109 ExternalASTSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
 110                                                   DeclarationName Name) {
 111   return false;
 112 }
 113
 114 void ExternalASTSource::completeVisibleDeclsMap(const DeclContext *DC) {}
 115
 116 void ExternalASTSource::FindExternalLexicalDecls(
 117     const DeclContext *DC, llvm::function_ref<bool(Decl::Kind)> IsKindWeWant,
 118     SmallVectorImpl<Decl *> &Result) {}
 119
 120 void ExternalASTSource::getMemoryBufferSizes(MemoryBufferSizes &sizes) const {}
 121
 122 uint32_t ExternalASTSource::incrementGeneration(ASTContext &C) {
 123   uint32_t OldGeneration = CurrentGeneration;
 124
 125   // Make sure the generation of the topmost external source for the context is
 126   // incremented. That might not be us.
 127   auto *P = C.getExternalSource();
 128   if (P && P != this)
 129     CurrentGeneration = P->incrementGeneration(C);
 130   else {
 131     // FIXME: Only bump the generation counter if the current generation number
 132     // has been observed?
 133     if (!++CurrentGeneration)
 134       llvm::report_fatal_error("generation counter overflowed", false);
 135   }
 136
 137   return OldGeneration;
 138 }