1 files changed, 20 insertions, 12 deletions

diff --git a/include/llvm/CodeGen/MachineDominators.h b/include/llvm/CodeGen/MachineDominators.h
index 735dd069cf7f5..a69936f6e267c 100644
--- a/include/llvm/CodeGen/MachineDominators.h
+++ b/include/llvm/CodeGen/MachineDominators.h
@@ -246,21 +246,29 @@ public:
 /// iterable by generic graph iterators.
 ///
 
-template<class T> struct GraphTraits;
+template <class Node, class ChildIterator>
+struct MachineDomTreeGraphTraitsBase {
+  typedef Node NodeType;
+  typedef ChildIterator ChildIteratorType;
 
-template <> struct GraphTraits<MachineDomTreeNode *> {
-  typedef MachineDomTreeNode NodeType;
-  typedef NodeType::iterator  ChildIteratorType;
-
-  static NodeType *getEntryNode(NodeType *N) {
-    return N;
-  }
-  static inline ChildIteratorType child_begin(NodeType* N) {
+  static NodeType *getEntryNode(NodeType *N) { return N; }
+  static inline ChildIteratorType child_begin(NodeType *N) {
     return N->begin();
   }
-  static inline ChildIteratorType child_end(NodeType* N) {
-    return N->end();
-  }
+  static inline ChildIteratorType child_end(NodeType *N) { return N->end(); }
+};
+
+template <class T> struct GraphTraits;
+
+template <>
+struct GraphTraits<MachineDomTreeNode *>
+    : public MachineDomTreeGraphTraitsBase<MachineDomTreeNode,
+                                           MachineDomTreeNode::iterator> {};
+
+template <>
+struct GraphTraits<const MachineDomTreeNode *>
+    : public MachineDomTreeGraphTraitsBase<const MachineDomTreeNode,
+                                           MachineDomTreeNode::const_iterator> {
 };
 
 template <> struct GraphTraits<MachineDominatorTree*>