diff --git a/llvm/include/llvm/Instruction.h b/llvm/include/llvm/Instruction.h
index 86f2a056cb97..d2f61965dddc 100644
--- a/llvm/include/llvm/Instruction.h
+++ b/llvm/include/llvm/Instruction.h
@@ -138,7 +138,7 @@ public:
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const Instruction *I) { return true; }
   static inline bool classof(const Value *V) {
-    return V->getValueType() == Value::InstructionVal;
+    return V->getValueType() >= Value::InstructionVal;
   }
   
   //----------------------------------------------------------------------
diff --git a/llvm/include/llvm/User.h b/llvm/include/llvm/User.h
index 0482189b6d8d..e45afdca68f7 100644
--- a/llvm/include/llvm/User.h
+++ b/llvm/include/llvm/User.h
@@ -86,9 +86,8 @@ public:
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const User *) { return true; }
   static inline bool classof(const Value *V) {
-    return V->getValueType() == Value::GlobalVariableVal ||
-           V->getValueType() == Value::ConstantVal ||
-           V->getValueType() == Value::InstructionVal;
+    return isa<Instruction>(V) || isa<GlobalVariable>(V) ||
+           isa<Constant>(V);
   }
 };