contrib/llvm-project/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 char ExternalASTSource::ID;
  28
  29 ExternalASTSource::~ExternalASTSource() = default;
  30
  31 llvm::Optional<ExternalASTSource::ASTSourceDescriptor>
  32 ExternalASTSource::getSourceDescriptor(unsigned ID) {
  33   return None;
  34 }
  35
  36 ExternalASTSource::ExtKind
  37 ExternalASTSource::hasExternalDefinitions(const Decl *D) {
  38   return EK_ReplyHazy;
  39 }
  40
  41 ExternalASTSource::ASTSourceDescriptor::ASTSourceDescriptor(const Module &M)
  42   : Signature(M.Signature), ClangModule(&M) {
  43   if (M.Directory)
  44     Path = M.Directory->getName();
  45   if (auto *File = M.getASTFile())
  46     ASTFile = File->getName();
  47 }
  48
  49 std::string ExternalASTSource::ASTSourceDescriptor::getModuleName() const {
  50   if (ClangModule)
  51     return ClangModule->Name;
  52   else
  53     return PCHModuleName;
  54 }
  55
  56 void ExternalASTSource::FindFileRegionDecls(FileID File, unsigned Offset,
  57                                             unsigned Length,
  58                                             SmallVectorImpl<Decl *> &Decls) {}
  59
  60 void ExternalASTSource::CompleteRedeclChain(const Decl *D) {}
  61
  62 void ExternalASTSource::CompleteType(TagDecl *Tag) {}
  63
  64 void ExternalASTSource::CompleteType(ObjCInterfaceDecl *Class) {}
  65
  66 void ExternalASTSource::ReadComments() {}
  67
  68 void ExternalASTSource::StartedDeserializing() {}
  69
  70 void ExternalASTSource::FinishedDeserializing() {}
  71
  72 void ExternalASTSource::StartTranslationUnit(ASTConsumer *Consumer) {}
  73
  74 void ExternalASTSource::PrintStats() {}
  75
  76 bool ExternalASTSource::layoutRecordType(
  77     const RecordDecl *Record, uint64_t &Size, uint64_t &Alignment,
  78     llvm::DenseMap<const FieldDecl *, uint64_t> &FieldOffsets,
  79     llvm::DenseMap<const CXXRecordDecl *, CharUnits> &BaseOffsets,
  80     llvm::DenseMap<const CXXRecordDecl *, CharUnits> &VirtualBaseOffsets) {
  81   return false;
  82 }
  83
  84 Decl *ExternalASTSource::GetExternalDecl(uint32_t ID) {
  85   return nullptr;
  86 }
  87
  88 Selector ExternalASTSource::GetExternalSelector(uint32_t ID) {
  89   return Selector();
  90 }
  91
  92 uint32_t ExternalASTSource::GetNumExternalSelectors() {
  93    return 0;
  94 }
  95
  96 Stmt *ExternalASTSource::GetExternalDeclStmt(uint64_t Offset) {
  97   return nullptr;
  98 }
  99
 100 CXXCtorInitializer **
 101 ExternalASTSource::GetExternalCXXCtorInitializers(uint64_t Offset) {
 102   return nullptr;
 103 }
 104
 105 CXXBaseSpecifier *
 106 ExternalASTSource::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
 107   return nullptr;
 108 }
 109
 110 bool
 111 ExternalASTSource::FindExternalVisibleDeclsByName(const DeclContext *DC,
 112                                                   DeclarationName Name) {
 113   return false;
 114 }
 115
 116 void ExternalASTSource::completeVisibleDeclsMap(const DeclContext *DC) {}
 117
 118 void ExternalASTSource::FindExternalLexicalDecls(
 119     const DeclContext *DC, llvm::function_ref<bool(Decl::Kind)> IsKindWeWant,
 120     SmallVectorImpl<Decl *> &Result) {}
 121
 122 void ExternalASTSource::getMemoryBufferSizes(MemoryBufferSizes &sizes) const {}
 123
 124 uint32_t ExternalASTSource::incrementGeneration(ASTContext &C) {
 125   uint32_t OldGeneration = CurrentGeneration;
 126
 127   // Make sure the generation of the topmost external source for the context is
 128   // incremented. That might not be us.
 129   auto *P = C.getExternalSource();
 130   if (P && P != this)
 131     CurrentGeneration = P->incrementGeneration(C);
 132   else {
 133     // FIXME: Only bump the generation counter if the current generation number
 134     // has been observed?
 135     if (!++CurrentGeneration)
 136       llvm::report_fatal_error("generation counter overflowed", false);
 137   }
 138
 139   return OldGeneration;
 140 }