Fix unused variable in r375066

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@375070 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/GlobalISel/CombinerHelper.cpp b/lib/CodeGen/GlobalISel/CombinerHelper.cpp
index e320fb3..20c6d13 100644
--- a/lib/CodeGen/GlobalISel/CombinerHelper.cpp
+++ b/lib/CodeGen/GlobalISel/CombinerHelper.cpp
@@ -135,8 +135,8 @@
         Builder.setInsertPt(*MI.getParent(), MI);
         Undef = Builder.buildUndef(OpType.getScalarType());
       }
-      LLT UndefType = MRI.getType(Undef->getOperand(0).getReg());
-      assert(UndefType == OpType.getScalarType() &&
+      assert(MRI.getType(Undef->getOperand(0).getReg()) ==
+                 OpType.getScalarType() &&
              "All undefs should have the same type");
       // Break the undef vector in as many scalar elements as needed
       // for the flattening.