SelectionDAG: slightly refactor DAGCombiner::visitSELECT_CC to avoid redudant checks...

This doesn't really effect performance due to all the relevant calls being transparent but is clearer. 

llvm-svn: 184027

1 files changed, 14 insertions, 12 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 92b0004c89b..f650b4d88a3 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -4233,20 +4233,22 @@ SDValue DAGCombiner::visitSELECT_CC(SDNode *N) {
   // Determine if the condition we're dealing with is constant
   SDValue SCC = SimplifySetCC(getSetCCResultType(N0.getValueType()),
                               N0, N1, CC, SDLoc(N), false);
-  if (SCC.getNode()) AddToWorkList(SCC.getNode());
+  if (SCC.getNode()) {
+    AddToWorkList(SCC.getNode());
 
-  if (ConstantSDNode *SCCC = dyn_cast_or_null<ConstantSDNode>(SCC.getNode())) {
-    if (!SCCC->isNullValue())
-      return N2;    // cond always true -> true val
-    else
-      return N3;    // cond always false -> false val
-  }
+    if (ConstantSDNode *SCCC = dyn_cast<ConstantSDNode>(SCC.getNode())) {
+      if (!SCCC->isNullValue())
+        return N2;    // cond always true -> true val
+      else
+        return N3;    // cond always false -> false val
+    }
 
-  // Fold to a simpler select_cc
-  if (SCC.getNode() && SCC.getOpcode() == ISD::SETCC)
-    return DAG.getNode(ISD::SELECT_CC, SDLoc(N), N2.getValueType(),
-                       SCC.getOperand(0), SCC.getOperand(1), N2, N3,
-                       SCC.getOperand(2));
+    // Fold to a simpler select_cc
+    if (SCC.getOpcode() == ISD::SETCC)
+      return DAG.getNode(ISD::SELECT_CC, SDLoc(N), N2.getValueType(),
+                         SCC.getOperand(0), SCC.getOperand(1), N2, N3,
+                         SCC.getOperand(2));
+  }
 
   // If we can fold this based on the true/false value, do so.
   if (SimplifySelectOps(N, N2, N3))