Avoid extra calls to MD->getNumOperands()

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94618 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/ValueMapper.cpp b/lib/Transforms/Utils/ValueMapper.cpp
index a6e6701..6045048 100644
--- a/lib/Transforms/Utils/ValueMapper.cpp
+++ b/lib/Transforms/Utils/ValueMapper.cpp
@@ -35,7 +35,7 @@
 
   if (const MDNode *MD = dyn_cast<MDNode>(V)) {
     SmallVector<Value*, 4> Elts;
-    for (unsigned i = 0; i != MD->getNumOperands(); i++)
+    for (unsigned i = 0, e = MD->getNumOperands(); i != e; ++i)
       Elts.push_back(MD->getOperand(i) ? MapValue(MD->getOperand(i), VM) : 0);
     return VM[V] = MDNode::get(V->getContext(), Elts.data(), Elts.size());
   }