DAGCombiner: simplify by using condition variables; NFC

llvm-svn: 225836
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 20eaa29..f271bd5 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -3383,8 +3383,9 @@
   }
 
   // Perform trivial constant folding.
-  SDValue SV = FoldConstantArithmetic(Opcode, VT, N1.getNode(), N2.getNode());
-  if (SV.getNode()) return SV;
+  if (SDValue SV =
+          FoldConstantArithmetic(Opcode, VT, N1.getNode(), N2.getNode()))
+    return SV;
 
   // Canonicalize constant to RHS if commutative.
   if (N1C && !N2C && isCommutativeBinOp(Opcode)) {