diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 1378f25..10b7576 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -4536,7 +4536,7 @@
 
   // Check #1.  Preinc'ing a frame index would require copying the stack pointer
   // (plus the implicit offset) to a register to preinc anyway.
-  if (isa<FrameIndexSDNode>(BasePtr))
+  if (isa<FrameIndexSDNode>(BasePtr) || isa<RegisterSDNode>(BasePtr))
     return false;
 
   // Check #2.
@@ -4663,6 +4663,9 @@
       //    nor a successor of N. Otherwise, if Op is folded that would
       //    create a cycle.
 
+      if (isa<FrameIndexSDNode>(BasePtr) || isa<RegisterSDNode>(BasePtr))
+        continue;
+
       // Check for #1.
       bool TryNext = false;
       for (SDNode::use_iterator II = BasePtr.getNode()->use_begin(),