diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index c6eb806..e60a7e6 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -1961,8 +1961,12 @@
   virtual void VisitInstruction(HInstruction* instruction) {}
   virtual void VisitBasicBlock(HBasicBlock* block);
 
+  // Visit the graph following basic block insertion order.
   void VisitInsertionOrder();
 
+  // Visit the graph following dominator tree reverse post-order.
+  void VisitReversePostOrder();
+
   HGraph* GetGraph() const { return graph_; }
 
   // Visit functions for instruction classes.