diff --git a/include/llvm/CodeGen/RegAllocPBQP.h b/include/llvm/CodeGen/RegAllocPBQP.h
index 7e8745eddef..8139c65c4b7 100644
--- a/include/llvm/CodeGen/RegAllocPBQP.h
+++ b/include/llvm/CodeGen/RegAllocPBQP.h
@@ -94,7 +94,7 @@ namespace llvm {
     typedef std::map<PBQP::Graph::ConstNodeItr, unsigned,
                      PBQP::NodeItrComparator>  Node2VReg;
     typedef DenseMap<unsigned, PBQP::Graph::NodeItr> VReg2Node;
-    typedef std::map<unsigned, AllowedSet> AllowedSetMap;
+    typedef DenseMap<unsigned, AllowedSet> AllowedSetMap;
 
     PBQP::Graph graph;
     Node2VReg node2VReg;