--- old/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/runtime/VMReg.java	2017-08-31 23:37:19.330565299 +0900
+++ new/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/runtime/VMReg.java	2017-08-31 23:37:19.234564983 +0900
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2003, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -84,4 +84,8 @@
   public boolean greaterThanOrEqual(VMReg arg)  { return value >= arg.value; }
 
   public int     minus(VMReg arg)               { return value - arg.value;  }
+
+  public int reg2Stack() {
+    return value - VM.getVM().getVMRegImplInfo().getStack0().getValue();
+  }
 }