--- old/src/jdk.vm.ci/share/classes/jdk.vm.ci.code/src/jdk/vm/ci/code/ReferenceMap.java	2016-05-18 23:01:47.000000000 +0200
+++ new/src/jdk.vm.ci/share/classes/jdk.vm.ci.code/src/jdk/vm/ci/code/ReferenceMap.java	2016-05-18 23:01:47.000000000 +0200
@@ -22,5 +22,10 @@
  */
 package jdk.vm.ci.code;
 
+/**
+ * Marker type for an object containing information about where the object references are in machine
+ * state (e.g., registers or stack locations). This is typically associated with an execution point
+ * in compiled code.
+ */
 public abstract class ReferenceMap {
 }