diff --git a/include/llvm/TargetTransformInfo.h b/include/llvm/TargetTransformInfo.h
index 1dc2b07ddfd..97744c0f78d 100644
--- a/include/llvm/TargetTransformInfo.h
+++ b/include/llvm/TargetTransformInfo.h
@@ -170,8 +170,8 @@ public:
   }
 
   /// Returns the cost of a shuffle instruction of kind Kind and of type Tp.
-  /// The index and subtype parameters are used by some of the shuffle kinds
-  /// to add additional information.
+  /// The index and subtype parameters are used by the subvector insertion and
+  /// extraction shuffle kinds.
   virtual unsigned getShuffleCost(ShuffleKind Kind, Type *Tp,
                                   int Index = 0, Type *SubTp = 0) const {
     return 1;