Fix -Wsign-compare warning (issued by clang++).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100799 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 5d3a6c3..01bd2e8 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -5552,7 +5552,7 @@
         InVec = InVec.getOperand(0);
       if (ISD::isNormalLoad(InVec.getNode())) {
         LN0 = cast<LoadSDNode>(InVec);
-        Elt = (Idx < (int)NumElems) ? Idx : Idx - NumElems;
+        Elt = (Idx < (int)NumElems) ? Idx : Idx - (int)NumElems;
       }
     }