Move the creation of the predefined typedef for Objective-C's 'id'

type over into the AST context, then make that declaration a
predefined declaration in the AST format. This ensures that different
AST files will at least agree on the (global) declaration ID for 'id',
and eliminates one of the "special" types in the AST file format.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@137429 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/AST/ASTContext.h

@@ -182,9 +182,9 @@ class ASTContext : public llvm::RefCountedBase<ASTContext> {
   /// a builtin that takes a valist is encountered.
   QualType BuiltinVaListType;
 
-  /// ObjCIdType - a pseudo built-in typedef type (set by Sema).
-  QualType ObjCIdTypedefType;
-
+  /// \brief The typedef for the predefined 'id' type.
+  mutable TypedefDecl *ObjCIdDecl;
+  
   /// ObjCSelType - another pseudo built-in typedef type (set by Sema).
   QualType ObjCSelTypedefType;
 
@@ -952,11 +952,16 @@ public:
   bool isInt128Installed() const { return IsInt128Installed; }
   void setInt128Installed() { IsInt128Installed = true; }
 
+  /// \brief Retrieve the typedef corresponding to the predefined 'id' type
+  /// in Objective-C.
+  TypedefDecl *getObjCIdDecl() const;
+  
   /// This setter/getter represents the ObjC 'id' type. It is setup lazily, by
   /// Sema.  id is always a (typedef for a) pointer type, a pointer to a struct.
-  QualType getObjCIdType() const { return ObjCIdTypedefType; }
-  void setObjCIdType(QualType T);
-
+  QualType getObjCIdType() const {
+    return getTypeDeclType(getObjCIdDecl());
+  }
+  
   void setObjCSelType(QualType T);
   QualType getObjCSelType() const { return ObjCSelTypedefType; }
 
@@ -1415,7 +1420,7 @@ public:
   bool typesAreBlockPointerCompatible(QualType, QualType); 
 
   bool isObjCIdType(QualType T) const {
-    return T == ObjCIdTypedefType;
+    return T == getObjCIdType();
   }
   bool isObjCClassType(QualType T) const {
     return T == ObjCClassTypedefType;

include/clang/Serialization/ASTBitCodes.h

@@ -640,30 +640,28 @@ namespace clang {
     enum SpecialTypeIDs {
       /// \brief __builtin_va_list
       SPECIAL_TYPE_BUILTIN_VA_LIST             = 0,
-      /// \brief Objective-C "id" type
-      SPECIAL_TYPE_OBJC_ID                     = 1,
       /// \brief Objective-C selector type
-      SPECIAL_TYPE_OBJC_SELECTOR               = 2,
+      SPECIAL_TYPE_OBJC_SELECTOR               = 1,
       /// \brief Objective-C Protocol type
-      SPECIAL_TYPE_OBJC_PROTOCOL               = 3,
+      SPECIAL_TYPE_OBJC_PROTOCOL               = 2,
       /// \brief Objective-C Class type
-      SPECIAL_TYPE_OBJC_CLASS                  = 4,
+      SPECIAL_TYPE_OBJC_CLASS                  = 3,
       /// \brief CFConstantString type
-      SPECIAL_TYPE_CF_CONSTANT_STRING          = 5,
+      SPECIAL_TYPE_CF_CONSTANT_STRING          = 4,
       /// \brief C FILE typedef type
-      SPECIAL_TYPE_FILE                        = 6,
+      SPECIAL_TYPE_FILE                        = 5,
       /// \brief C jmp_buf typedef type
-      SPECIAL_TYPE_jmp_buf                     = 7,
+      SPECIAL_TYPE_jmp_buf                     = 6,
       /// \brief C sigjmp_buf typedef type
-      SPECIAL_TYPE_sigjmp_buf                  = 8,
+      SPECIAL_TYPE_sigjmp_buf                  = 7,
       /// \brief Objective-C "id" redefinition type
-      SPECIAL_TYPE_OBJC_ID_REDEFINITION        = 9,
+      SPECIAL_TYPE_OBJC_ID_REDEFINITION        = 8,
       /// \brief Objective-C "Class" redefinition type
-      SPECIAL_TYPE_OBJC_CLASS_REDEFINITION     = 10,
+      SPECIAL_TYPE_OBJC_CLASS_REDEFINITION     = 9,
       /// \brief Objective-C "SEL" redefinition type
-      SPECIAL_TYPE_OBJC_SEL_REDEFINITION       = 11,
+      SPECIAL_TYPE_OBJC_SEL_REDEFINITION       = 10,
       /// \brief Whether __[u]int128_t identifier is installed.
-      SPECIAL_TYPE_INT128_INSTALLED            = 12
+      SPECIAL_TYPE_INT128_INSTALLED            = 11
     };
 
     /// \brief Predefined declaration IDs.
@@ -677,14 +675,17 @@ namespace clang {
       PREDEF_DECL_NULL_ID       = 0,
       
       /// \brief The translation unit.
-      PREDEF_DECL_TRANSLATION_UNIT_ID = 1
+      PREDEF_DECL_TRANSLATION_UNIT_ID = 1,
+      
+      /// \brief The Objective-C 'id' type.
+      PREDEF_DECL_OBJC_ID_ID = 2
     };
 
     /// \brief The number of declaration IDs that are predefined.
     ///
     /// For more information about predefined declarations, see the
     /// \c PredefinedDeclIDs type and the PREDEF_DECL_*_ID constants.
-    const unsigned int NUM_PREDEF_DECL_IDS = 2;
+    const unsigned int NUM_PREDEF_DECL_IDS = 3;
     
     /// \brief Record codes for each kind of declaration.
     ///

lib/AST/ASTContext.cpp

@@ -222,7 +222,7 @@ ASTContext::ASTContext(const LangOptions& LOpts, SourceManager &SM,
   DependentTemplateSpecializationTypes(this_()),
   SubstTemplateTemplateParmPacks(this_()),
   GlobalNestedNameSpecifier(0), IsInt128Installed(false),
-  CFConstantStringTypeDecl(0),
+  ObjCIdDecl(0), CFConstantStringTypeDecl(0),
   FILEDecl(0), 
   jmp_bufDecl(0), sigjmp_bufDecl(0), BlockDescriptorType(0), 
   BlockDescriptorExtendedType(0), cudaConfigureCallDecl(0),
@@ -430,7 +430,6 @@ void ASTContext::InitBuiltinTypes() {
   BuiltinVaListType = QualType();
 
   // "Builtin" typedefs set by Sema::ActOnTranslationUnitScope().
-  ObjCIdTypedefType = QualType();
   ObjCClassTypedefType = QualType();
   ObjCSelTypedefType = QualType();
 
@@ -4619,8 +4618,18 @@ void ASTContext::setBuiltinVaListType(QualType T) {
   BuiltinVaListType = T;
 }
 
-void ASTContext::setObjCIdType(QualType T) {
-  ObjCIdTypedefType = T;
+TypedefDecl *ASTContext::getObjCIdDecl() const {
+  if (!ObjCIdDecl) {
+    QualType T = getObjCObjectType(ObjCBuiltinIdTy, 0, 0);
+    T = getObjCObjectPointerType(T);
+    TypeSourceInfo *IdInfo = getTrivialTypeSourceInfo(T);
+    ObjCIdDecl = TypedefDecl::Create(const_cast<ASTContext &>(*this),
+                                     getTranslationUnitDecl(),
+                                     SourceLocation(), SourceLocation(),
+                                     &Idents.get("id"), IdInfo);
+  }
+  
+  return ObjCIdDecl;
 }
 
 void ASTContext::setObjCSelType(QualType T) {

lib/Sema/Sema.cpp

@@ -106,18 +106,7 @@ void Sema::ActOnTranslationUnitScope(Scope *S) {
     Context.setObjCProtoType(Context.getObjCInterfaceType(ProtocolDecl));
     PushOnScopeChains(ProtocolDecl, TUScope, false);
   }
-  // Create the built-in typedef for 'id'.
-  if (Context.getObjCIdType().isNull()) {
-    QualType T = Context.getObjCObjectType(Context.ObjCBuiltinIdTy, 0, 0);
-    T = Context.getObjCObjectPointerType(T);
-    TypeSourceInfo *IdInfo = Context.getTrivialTypeSourceInfo(T);
-    TypedefDecl *IdTypedef
-      = TypedefDecl::Create(Context, CurContext,
-                            SourceLocation(), SourceLocation(),
-                            &Context.Idents.get("id"), IdInfo);
-    PushOnScopeChains(IdTypedef, TUScope);
-    Context.setObjCIdType(Context.getTypeDeclType(IdTypedef));
-  }
+  
   // Create the built-in typedef for 'Class'.
   if (Context.getObjCClassType().isNull()) {
     QualType T = Context.getObjCObjectType(Context.ObjCBuiltinClassTy, 0, 0);
@@ -178,6 +167,15 @@ void Sema::Initialize() {
   if (ExternalSemaSource *ExternalSema
       = dyn_cast_or_null<ExternalSemaSource>(Context.getExternalSource()))
     ExternalSema->InitializeSema(*this);
+
+  // Initialize predefined Objective-C types:
+  if (PP.getLangOptions().ObjC1) {
+    // If 'id' does not yet refer to any declarations, make it refer to the
+    // predefined 'id'.
+    DeclarationName Id = &Context.Idents.get("id");
+    if (IdentifierResolver::begin(Id) == IdentifierResolver::end())
+      PushOnScopeChains(Context.getObjCIdDecl(), TUScope);
+  }
 }
 
 Sema::~Sema() {

lib/Serialization/ASTReader.cpp

@@ -2987,11 +2987,6 @@ void ASTReader::InitializeContext(ASTContext &Ctx) {
       GetType(SpecialTypes[SPECIAL_TYPE_BUILTIN_VA_LIST]));
   }
   
-  if (unsigned Id = SpecialTypes[SPECIAL_TYPE_OBJC_ID]) {
-    if (Context->ObjCIdTypedefType.isNull())
-      Context->ObjCIdTypedefType = GetType(Id);
-  }
-  
   if (unsigned Sel = SpecialTypes[SPECIAL_TYPE_OBJC_SELECTOR]) {
     if (Context->ObjCSelTypedefType.isNull())
       Context->ObjCSelTypedefType = GetType(Sel);
@@ -4225,6 +4220,10 @@ Decl *ASTReader::GetDecl(DeclID ID) {
     case PREDEF_DECL_TRANSLATION_UNIT_ID:
       assert(Context && "No context available?");
       return Context->getTranslationUnitDecl();
+        
+    case PREDEF_DECL_OBJC_ID_ID:
+      assert(Context && "No context available?");
+      return Context->getObjCIdDecl();
     }
     
     return 0;

lib/Serialization/ASTWriter.cpp

@@ -2808,7 +2808,9 @@ void ASTWriter::WriteASTCore(Sema &SemaRef, MemorizeStatCalls *StatCalls,
 
   // Set up predefined declaration IDs.
   DeclIDs[Context.getTranslationUnitDecl()] = PREDEF_DECL_TRANSLATION_UNIT_ID;
-
+  if (Context.ObjCIdDecl)
+    DeclIDs[Context.ObjCIdDecl] = PREDEF_DECL_OBJC_ID_ID;
+          
   if (!Chain) {
     // Make sure that we emit IdentifierInfos (and any attached
     // declarations) for builtins. We don't need to do this when we're
@@ -3015,7 +3017,6 @@ void ASTWriter::WriteASTCore(Sema &SemaRef, MemorizeStatCalls *StatCalls,
   // Form the record of special types.
   RecordData SpecialTypes;
   AddTypeRef(Context.getBuiltinVaListType(), SpecialTypes);
-  AddTypeRef(Context.ObjCIdTypedefType, SpecialTypes);
   AddTypeRef(Context.ObjCSelTypedefType, SpecialTypes);
   AddTypeRef(Context.ObjCProtoType, SpecialTypes);
   AddTypeRef(Context.ObjCClassTypedefType, SpecialTypes);