Roll out r125794 to help diagnose the llvm-gcc-i386-linux-selfhost failure.

llvm-svn: 125830
diff --git a/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h b/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h
index 2dcb229..e5cd23a 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h
+++ b/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h
@@ -83,6 +83,14 @@
   // Returns the SDNode* for a register ref
   SDNode *getSDNode() { assert (kind==SDNODE); return u.s.Node; }
 
+  // setSDNode - If underlying SDNode is replaced by another node then
+  // SelectionDAG can use this to transfer DbgValue.
+  void setSDNode(SDNode *N, unsigned R) { 
+    assert (kind==SDNODE); 
+    u.s.Node = N; 
+    u.s.ResNo = R;
+  }
+
   // Returns the ResNo for a register ref
   unsigned getResNo() { assert (kind==SDNODE); return u.s.ResNo; }