[libclang] When indexing an AST file, only deserialize the file level

declarations of the current primary module.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@165046 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Frontend/ASTUnit.h

@@ -613,6 +613,16 @@ public:
   std::pair<PreprocessingRecord::iterator, PreprocessingRecord::iterator>
     getLocalPreprocessingEntities() const;
 
+  /// \brief Type for a function iterating over a number of declarations.
+  /// \returns true to continue iteration and false to abort.
+  typedef bool (*DeclReceiverFn)(void *context, const Decl *D);
+
+  /// \brief Iterate over local declarations (locally parsed if this is a parsed
+  /// source file or the loaded declarations of the primary module if this is an
+  /// AST file).
+  /// \returns true if the iteration was complete or false if it was aborted.
+  bool applyOnLocalTopLevelDecls(void *context, DeclReceiverFn Fn);
+
   llvm::MemoryBuffer *getBufferForFile(StringRef Filename,
                                        std::string *ErrorStr = 0);
 

include/clang/Serialization/ASTReader.h

@@ -860,6 +860,64 @@ private:
   std::pair<PreprocessingRecord::iterator, PreprocessingRecord::iterator>
     getModulePreprocessedEntities(ModuleFile &Mod) const;
 
+  class ModuleDeclIterator {
+    ASTReader *Reader;
+    ModuleFile *Mod;
+    const serialization::LocalDeclID *Pos;
+
+  public:
+    typedef const Decl *value_type;
+    typedef value_type&         reference;
+    typedef value_type*         pointer;
+
+    ModuleDeclIterator() : Reader(0), Mod(0), Pos(0) { }
+
+    ModuleDeclIterator(ASTReader *Reader, ModuleFile *Mod,
+                       const serialization::LocalDeclID *Pos)
+      : Reader(Reader), Mod(Mod), Pos(Pos) { }
+
+    value_type operator*() const {
+      return Reader->GetDecl(Reader->getGlobalDeclID(*Mod, *Pos));
+    }
+
+    ModuleDeclIterator &operator++() {
+      ++Pos;
+      return *this;
+    }
+
+    ModuleDeclIterator operator++(int) {
+      ModuleDeclIterator Prev(*this);
+      ++Pos;
+      return Prev;
+    }
+
+    ModuleDeclIterator &operator--() {
+      --Pos;
+      return *this;
+    }
+
+    ModuleDeclIterator operator--(int) {
+      ModuleDeclIterator Prev(*this);
+      --Pos;
+      return Prev;
+    }
+
+    friend bool operator==(const ModuleDeclIterator &LHS,
+                           const ModuleDeclIterator &RHS) {
+      assert(LHS.Reader == RHS.Reader && LHS.Mod == RHS.Mod);
+      return LHS.Pos == RHS.Pos;
+    }
+
+    friend bool operator!=(const ModuleDeclIterator &LHS,
+                           const ModuleDeclIterator &RHS) {
+      assert(LHS.Reader == RHS.Reader && LHS.Mod == RHS.Mod);
+      return LHS.Pos != RHS.Pos;
+    }
+  };
+
+  std::pair<ModuleDeclIterator, ModuleDeclIterator>
+    getModuleFileLevelDecls(ModuleFile &Mod);
+
   void PassInterestingDeclsToConsumer();
   void PassInterestingDeclToConsumer(Decl *D);
 
@@ -1081,7 +1139,8 @@ public:
 
   /// \brief Map from a local declaration ID within a given module to a
   /// global declaration ID.
-  serialization::DeclID getGlobalDeclID(ModuleFile &F, unsigned LocalID) const;
+  serialization::DeclID getGlobalDeclID(ModuleFile &F,
+                                      serialization::LocalDeclID LocalID) const;
 
   /// \brief Returns true if global DeclID \p ID originated from module \p M.
   bool isDeclIDFromModule(serialization::GlobalDeclID ID, ModuleFile &M) const;

include/clang/Serialization/Module.h

@@ -294,6 +294,7 @@ public:
 
   /// \brief Array of file-level DeclIDs sorted by file.
   const serialization::DeclID *FileSortedDecls;
+  unsigned NumFileSortedDecls;
 
   /// \brief Array of redeclaration chain location information within this 
   /// module file, sorted by the first declaration ID.

lib/Frontend/ASTUnit.cpp

@@ -2792,6 +2792,30 @@ ASTUnit::getLocalPreprocessingEntities() const {
                         PreprocessingRecord::iterator());
 }
 
+bool ASTUnit::applyOnLocalTopLevelDecls(void *context, DeclReceiverFn Fn) {
+  if (isMainFileAST()) {
+    serialization::ModuleFile &
+      Mod = Reader->getModuleManager().getPrimaryModule();
+    ASTReader::ModuleDeclIterator MDI, MDE;
+    llvm::tie(MDI, MDE) = Reader->getModuleFileLevelDecls(Mod);
+    for (; MDI != MDE; ++MDI) {
+      if (!Fn(context, *MDI))
+        return false;
+    }
+
+    return true;
+  }
+
+  for (ASTUnit::top_level_iterator TL = top_level_begin(),
+                                TLEnd = top_level_end();
+         TL != TLEnd; ++TL) {
+    if (!Fn(context, *TL))
+      return false;
+  }
+
+  return true;
+}
+
 void ASTUnit::PreambleData::countLines() const {
   NumLines = 0;
   if (empty())

lib/Serialization/ASTReader.cpp

@@ -2063,6 +2063,7 @@ ASTReader::ReadASTBlock(ModuleFile &F) {
       
     case FILE_SORTED_DECLS:
       F.FileSortedDecls = (const DeclID *)BlobStart;
+      F.NumFileSortedDecls = Record[0];
       break;
 
     case SOURCE_LOCATION_OFFSETS: {
@@ -3391,6 +3392,13 @@ ASTReader::getModulePreprocessedEntities(ModuleFile &Mod) const {
                         PreprocessingRecord::iterator());
 }
 
+std::pair<ASTReader::ModuleDeclIterator, ASTReader::ModuleDeclIterator>
+ASTReader::getModuleFileLevelDecls(ModuleFile &Mod) {
+  return std::make_pair(ModuleDeclIterator(this, &Mod, Mod.FileSortedDecls),
+                        ModuleDeclIterator(this, &Mod,
+                                 Mod.FileSortedDecls + Mod.NumFileSortedDecls));
+}
+
 PreprocessedEntity *ASTReader::ReadPreprocessedEntity(unsigned Index) {
   PreprocessedEntityID PPID = Index+1;
   std::pair<ModuleFile *, unsigned> PPInfo = getModulePreprocessedEntity(Index);
@@ -4625,7 +4633,7 @@ CXXBaseSpecifier *ASTReader::GetExternalCXXBaseSpecifiers(uint64_t Offset) {
 }
 
 serialization::DeclID 
-ASTReader::getGlobalDeclID(ModuleFile &F, unsigned LocalID) const {
+ASTReader::getGlobalDeclID(ModuleFile &F, LocalDeclID LocalID) const {
   if (LocalID < NUM_PREDEF_DECL_IDS)
     return LocalID;
 

lib/Serialization/ASTWriter.cpp

@@ -2251,9 +2251,11 @@ void ASTWriter::WriteFileDeclIDsMap() {
 
   BitCodeAbbrev *Abbrev = new BitCodeAbbrev();
   Abbrev->Add(BitCodeAbbrevOp(FILE_SORTED_DECLS));
+  Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
   unsigned AbbrevCode = Stream.EmitAbbrev(Abbrev);
   Record.push_back(FILE_SORTED_DECLS);
+  Record.push_back(FileSortedIDs.size());
   Stream.EmitRecordWithBlob(AbbrevCode, Record, data(FileSortedIDs));
 }
 

lib/Serialization/Module.cpp

@@ -35,7 +35,8 @@ ModuleFile::ModuleFile(ModuleKind Kind, unsigned Generation)
     SelectorLookupTableData(0), SelectorLookupTable(0), LocalNumDecls(0),
     DeclOffsets(0), BaseDeclID(0),
     LocalNumCXXBaseSpecifiers(0), CXXBaseSpecifiersOffsets(0),
-    FileSortedDecls(0), RedeclarationsMap(0), LocalNumRedeclarationsInMap(0),
+    FileSortedDecls(0), NumFileSortedDecls(0),
+    RedeclarationsMap(0), LocalNumRedeclarationsInMap(0),
     ObjCCategoriesMap(0), LocalNumObjCCategoriesInMap(0),
     LocalNumTypes(0), TypeOffsets(0), BaseTypeIndex(0), StatCache(0)
 {}

tools/libclang/Indexing.cpp

@@ -472,30 +472,16 @@ static void indexPreprocessingRecord(ASTUnit &Unit, IndexingContext &IdxCtx) {
   }
 }
 
+static bool topLevelDeclReceiver(void *context, const Decl *D) {
+  IndexingContext &IdxCtx = *static_cast<IndexingContext*>(context);
+  IdxCtx.indexTopLevelDecl(D);
+  if (IdxCtx.shouldAbort())
+    return false;
+  return true;
+}
+
 static void indexTranslationUnit(ASTUnit &Unit, IndexingContext &IdxCtx) {
-  // FIXME: Only deserialize stuff from the last chained PCH, not the PCH/Module
-  // that it depends on.
-
-  bool OnlyLocal = !Unit.isMainFileAST() && Unit.getOnlyLocalDecls();
-
-  if (OnlyLocal) {
-    for (ASTUnit::top_level_iterator TL = Unit.top_level_begin(),
-                                  TLEnd = Unit.top_level_end();
-           TL != TLEnd; ++TL) {
-      IdxCtx.indexTopLevelDecl(*TL);
-      if (IdxCtx.shouldAbort())
-        return;
-    }
-
-  } else {
-    TranslationUnitDecl *TUDecl = Unit.getASTContext().getTranslationUnitDecl();
-    for (TranslationUnitDecl::decl_iterator
-           I = TUDecl->decls_begin(), E = TUDecl->decls_end(); I != E; ++I) {
-      IdxCtx.indexTopLevelDecl(*I);
-      if (IdxCtx.shouldAbort())
-        return;
-    }
-  }
+  Unit.applyOnLocalTopLevelDecls(&IdxCtx, topLevelDeclReceiver);
 }
 
 static void indexDiagnostics(CXTranslationUnit TU, IndexingContext &IdxCtx) {