Move SDNode order propagation to SDNodeOrdering, which also fixes a missed
case of order propagation during isel.

Thanks Owen for the suggestion!

llvm-svn: 177525
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 15001f5..eeea9e4 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -786,7 +786,9 @@
         continue;
       // Replace node.
       if (ResNode) {
+        // Propagate ordering
         CurDAG->AssignOrdering(ResNode, CurDAG->GetOrdering(Node));
+
         ReplaceUses(Node, ResNode);
       }