diff --git a/llvm/include/llvm/CodeGen/SelectionDAG.h b/llvm/include/llvm/CodeGen/SelectionDAG.h
index 53caf885489d..4de4161103a1 100644
--- a/llvm/include/llvm/CodeGen/SelectionDAG.h
+++ b/llvm/include/llvm/CodeGen/SelectionDAG.h
@@ -424,7 +424,7 @@ public:
 
   /// AssignNodeIds - Assign a unique node id for each node in the DAG. It
   /// returns the maximum id.
-  int AssignNodeIds();
+  unsigned AssignNodeIds();
 
   void dump() const;
 
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 77904bf8287b..1a5a09b1dc97 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -2700,8 +2700,8 @@ void SelectionDAG::ReplaceAllUsesOfValueWith(SDOperand From, SDOperand To,
 
 /// AssignNodeIds - Assign a unique node id for each node in the DAG. It returns
 /// the maximum id.
-int SelectionDAG::AssignNodeIds() {
-  int Id = 0;
+unsigned SelectionDAG::AssignNodeIds() {
+  unsigned Id = 0;
   for (allnodes_iterator I = allnodes_begin(), E = allnodes_end(); I != E; ++I){
     SDNode *N = I;
     N->setNodeId(Id++);