Add a method in ASTMutationListener for the last use of Decl's [is/set]ChangedSinceDeserialization

and remove them.

llvm-svn: 144466

clang/include/clang/AST/ASTMutationListener.h

@@ -64,6 +64,9 @@ public:
 
   /// \brief A objc interface or protocol forward reference was completed.
   virtual void CompletedObjCForwardRef(const ObjCContainerDecl *D) {}
+
+  /// \brief The attributes list of a declaration was updated.
+  virtual void UpdatedAttributeList(const Decl *D) {}
 };
 
 } // end namespace clang

clang/include/clang/AST/DeclBase.h

@@ -253,9 +253,6 @@ protected:
   /// \brief Whether this declaration was loaded from an AST file.
   unsigned FromASTFile : 1;
 
-  /// ChangedAfterLoad - if this declaration has changed since being loaded
-  unsigned ChangedAfterLoad : 1;
-
   /// \brief Whether this declaration is private to the module in which it was
   /// defined.
   unsigned ModulePrivate : 1;
@@ -285,7 +282,7 @@ protected:
     : NextDeclInContext(0), DeclCtx(DC),
       Loc(L), DeclKind(DK), InvalidDecl(0),
       HasAttrs(false), Implicit(false), Used(false), Referenced(false),
-      Access(AS_none), FromASTFile(0), ChangedAfterLoad(false),
+      Access(AS_none), FromASTFile(0),
       ModulePrivate(0),
       IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
       HasCachedLinkage(0)
@@ -296,7 +293,7 @@ protected:
   Decl(Kind DK, EmptyShell Empty)
     : NextDeclInContext(0), DeclKind(DK), InvalidDecl(0),
       HasAttrs(false), Implicit(false), Used(false), Referenced(false),
-      Access(AS_none), FromASTFile(0), ChangedAfterLoad(false),
+      Access(AS_none), FromASTFile(0),
       ModulePrivate(0),
       IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
       HasCachedLinkage(0)
@@ -505,19 +502,6 @@ public:
   /// a precompiled header or module) rather than having been parsed.
   bool isFromASTFile() const { return FromASTFile; }
 
-  /// \brief Query whether this declaration was changed in a significant way
-  /// since being loaded from an AST file.
-  ///
-  /// In an epic violation of layering, what is "significant" is entirely
-  /// up to the serialization system, but implemented in AST and Sema.
-  bool isChangedSinceDeserialization() const { return ChangedAfterLoad; }
-
-  /// \brief Mark this declaration as having changed since deserialization, or
-  /// reset the flag.
-  void setChangedSinceDeserialization(bool Changed) {
-    ChangedAfterLoad = Changed;
-  }
-
   unsigned getIdentifierNamespace() const {
     return IdentifierNamespace;
   }

clang/include/clang/Serialization/ASTWriter.h

@@ -587,8 +587,6 @@ public:
 
   void RewriteDecl(const Decl *D) {
     DeclsToRewrite.insert(D);
-    // Reset the flag, so that we don't add this decl multiple times.
-    const_cast<Decl *>(D)->setChangedSinceDeserialization(false);
   }
 
   bool isRewritten(const Decl *D) const {
@@ -669,6 +667,7 @@ public:
   virtual void AddedObjCCategoryToInterface(const ObjCCategoryDecl *CatD,
                                             const ObjCInterfaceDecl *IFD);
   virtual void CompletedObjCForwardRef(const ObjCContainerDecl *D);
+  virtual void UpdatedAttributeList(const Decl *D);
 };
 
 /// \brief AST and semantic-analysis consumer that generates a

clang/lib/Sema/SemaDeclObjC.cpp

@@ -21,6 +21,7 @@
 #include "clang/AST/ExprObjC.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/DeclObjC.h"
+#include "clang/AST/ASTMutationListener.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Sema/DeclSpec.h"
 #include "llvm/ADT/DenseSet.h"
@@ -701,8 +702,10 @@ Sema::ActOnForwardProtocolDeclaration(SourceLocation AtProtocolLoc,
     }
     if (attrList) {
       ProcessDeclAttributeList(TUScope, PDecl, attrList);
-      if (!isNew)
-        PDecl->setChangedSinceDeserialization(true);
+      if (!isNew) {
+        if (ASTMutationListener *L = Context.getASTMutationListener())
+          L->UpdatedAttributeList(PDecl);
+      }
     }
     Protocols.push_back(PDecl);
     ProtoLocs.push_back(IdentList[i].second);

clang/lib/Serialization/ASTWriter.cpp

@@ -2960,8 +2960,6 @@ void ASTWriter::WriteASTCore(Sema &SemaRef, MemorizeStatCalls *StatCalls,
        I != E; ++I) {
     if (!(*I)->isFromASTFile())
       NewGlobalDecls.push_back(std::make_pair((*I)->getKind(), GetDeclRef(*I)));
-    else if ((*I)->isChangedSinceDeserialization())
-      (void)GetDeclRef(*I); // Make sure it's written, but don't record it.
   }
   
   llvm::BitCodeAbbrev *Abv = new llvm::BitCodeAbbrev();
@@ -3454,12 +3452,6 @@ DeclID ASTWriter::GetDeclRef(const Decl *D) {
     // enqueue it in the list of declarations to emit.
     ID = NextDeclID++;
     DeclTypesToEmit.push(const_cast<Decl *>(D));
-  } else if (ID < FirstDeclID && D->isChangedSinceDeserialization()) {
-    // We don't add it to the replacement collection here, because we don't
-    // have the offset yet.
-    DeclTypesToEmit.push(const_cast<Decl *>(D));
-    // Reset the flag, so that we don't add this decl multiple times.
-    const_cast<Decl *>(D)->setChangedSinceDeserialization(false);
   }
 
   return ID;
@@ -4135,3 +4127,11 @@ void ASTWriter::CompletedObjCForwardRef(const ObjCContainerDecl *D) {
 
   RewriteDecl(D);
 }
+
+void ASTWriter::UpdatedAttributeList(const Decl *D) {
+  assert(!WritingAST && "Already writing the AST!");
+  if (!D->isFromASTFile())
+    return; // Declaration not imported from PCH.
+
+  RewriteDecl(D);
+}