diff --git a/include/llvm/DerivedTypes.h b/include/llvm/DerivedTypes.h
index 9e79339f4a2..417d0418c54 100644
--- a/include/llvm/DerivedTypes.h
+++ b/include/llvm/DerivedTypes.h
@@ -205,10 +205,10 @@ public:
   /// getTypeAtIndex - Given an index value into the type, return the type of
   /// the element.
   ///
-  virtual const Type *getTypeAtIndex(const Value *V) const = 0;
-  virtual const Type *getTypeAtIndex(unsigned Idx) const = 0;
-  virtual bool indexValid(const Value *V) const = 0;
-  virtual bool indexValid(unsigned Idx) const = 0;
+  const Type *getTypeAtIndex(const Value *V) const;
+  const Type *getTypeAtIndex(unsigned Idx) const;
+  bool indexValid(const Value *V) const;
+  bool indexValid(unsigned Idx) const;
 
   // Methods for support type inquiry through isa, cast, and dyn_cast.
   static inline bool classof(const CompositeType *) { return true; }
@@ -264,14 +264,6 @@ public:
     return ContainedTys[N];
   }
 
-  /// getTypeAtIndex - Given an index value into the type, return the type of
-  /// the element.  For a structure type, this must be a constant value...
-  ///
-  virtual const Type *getTypeAtIndex(const Value *V) const;
-  virtual const Type *getTypeAtIndex(unsigned Idx) const;
-  virtual bool indexValid(const Value *V) const;
-  virtual bool indexValid(unsigned Idx) const;
-
   // Implement the AbstractTypeUser interface.
   virtual void refineAbstractType(const DerivedType *OldTy, const Type *NewTy);
   virtual void typeBecameConcrete(const DerivedType *AbsTy);
@@ -306,22 +298,7 @@ protected:
   }
 
 public:
-  inline const Type *getElementType() const { return ContainedTys[0]; }
-
-  virtual bool indexValid(const Value *V) const;
-  virtual bool indexValid(unsigned) const {
-    return true;
-  }
-
-  /// getTypeAtIndex - Given an index value into the type, return the type of
-  /// the element.  For sequential types, there is only one subtype...
-  ///
-  virtual const Type *getTypeAtIndex(const Value *) const {
-    return ContainedTys[0];
-  }
-  virtual const Type *getTypeAtIndex(unsigned) const {
-    return ContainedTys[0];
-  }
+  const Type *getElementType() const { return ContainedTys[0]; }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast.
   static inline bool classof(const SequentialType *) { return true; }
diff --git a/lib/VMCore/Type.cpp b/lib/VMCore/Type.cpp
index 6c348be18f2..ebe431bdc2f 100644
--- a/lib/VMCore/Type.cpp
+++ b/lib/VMCore/Type.cpp
@@ -286,29 +286,41 @@ void Type::typeBecameConcrete(const DerivedType *AbsTy) {
   llvm_unreachable("DerivedType is already a concrete type!");
 }
 
-bool StructType::indexValid(const Value *V) const {
-  // Structure indexes require 32-bit integer constants.
-  if (V->getType()->isIntegerTy(32))
-    if (const ConstantInt *CU = dyn_cast<ConstantInt>(V))
-      return indexValid(CU->getZExtValue());
-  return false;
+const Type *CompositeType::getTypeAtIndex(const Value *V) const {
+  if (const StructType *STy = dyn_cast<StructType>(this)) {
+    unsigned Idx = (unsigned)cast<ConstantInt>(V)->getZExtValue();
+    assert(indexValid(Idx) && "Invalid structure index!");
+    return STy->getElementType(Idx);
+  }
+    
+  return cast<SequentialType>(this)->getElementType();
+}
+const Type *CompositeType::getTypeAtIndex(unsigned Idx) const {
+  if (const StructType *STy = dyn_cast<StructType>(this)) {
+    assert(indexValid(Idx) && "Invalid structure index!");
+    return STy->getElementType(Idx);
+  }
+  
+  return cast<SequentialType>(this)->getElementType();
+}
+bool CompositeType::indexValid(const Value *V) const {
+  if (const StructType *STy = dyn_cast<StructType>(this)) {
+    // Structure indexes require 32-bit integer constants.
+    if (V->getType()->isIntegerTy(32))
+      if (const ConstantInt *CU = dyn_cast<ConstantInt>(V))
+        return CU->getZExtValue() < STy->getNumElements();
+    return false;
+  }
+  
+  // Sequential types can be indexed by any integer.
+  return V->getType()->isIntegerTy();
 }
 
-bool StructType::indexValid(unsigned V) const {
-  return V < NumContainedTys;
-}
-
-// getTypeAtIndex - Given an index value into the type, return the type of the
-// element.  For a structure type, this must be a constant value...
-//
-const Type *StructType::getTypeAtIndex(const Value *V) const {
-  unsigned Idx = (unsigned)cast<ConstantInt>(V)->getZExtValue();
-  return getTypeAtIndex(Idx);
-}
-
-const Type *StructType::getTypeAtIndex(unsigned Idx) const {
-  assert(indexValid(Idx) && "Invalid structure index!");
-  return ContainedTys[Idx];
+bool CompositeType::indexValid(unsigned Idx) const {
+  if (const StructType *STy = dyn_cast<StructType>(this))
+    return Idx < STy->getNumElements();
+  // Sequential types can be indexed by any integer.
+  return true;
 }
 
 
@@ -1201,12 +1213,6 @@ void PointerType::typeBecameConcrete(const DerivedType *AbsTy) {
   pImpl->PointerTypes.TypeBecameConcrete(this, AbsTy);
 }
 
-bool SequentialType::indexValid(const Value *V) const {
-  if (V->getType()->isIntegerTy()) 
-    return true;
-  return false;
-}
-
 namespace llvm {
 raw_ostream &operator<<(raw_ostream &OS, const Type &T) {
   T.print(OS);