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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16937 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/Type.h b/include/llvm/Type.h
index 0fb34c526129d7c1f04c14516a4590ad65322489..fd5dbdd90f79c95fea5c8697c0426ad483f12978 100644 (file)
--- a/include/llvm/Type.h
+++ b/include/llvm/Type.h
@@ -192,6 +192,8 @@ public:
   inline bool isDerivedType()   const { return ID >= FirstDerivedTyID; }
 
   /// isFirstClassType - Return true if the value is holdable in a register.
+  /// Note that we consider opaque types to be first class, as they may be
+  /// resolved to a first class type later.
   inline bool isFirstClassType() const {
     return (ID != VoidTyID && ID <= LastPrimitiveTyID) || 
             ID == PointerTyID || ID == PackedTyID || ID == OpaqueTyID;