--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/agent/src/share/classes/sun/jvm/hotspot/runtime/x86/X86RicochetFrame.java	Mon Sep 05 17:09:05 2011 -0700
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2011, 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+package sun.jvm.hotspot.runtime.x86;
+
+import java.util.*;
+import sun.jvm.hotspot.debugger.*;
+import sun.jvm.hotspot.runtime.*;
+import sun.jvm.hotspot.types.*;
+
+public class X86RicochetFrame extends VMObject {
+  static {
+    VM.registerVMInitializedObserver(new Observer() {
+        public void update(Observable o, Object data) {
+          initialize(VM.getVM().getTypeDataBase());
+        }
+      });
+  }
+
+  private static void initialize(TypeDataBase db) {
+    Type type = db.lookupType("MethodHandles::RicochetFrame");
+
+    senderLinkField    = type.getAddressField("_sender_link");
+    savedArgsBaseField = type.getAddressField("_saved_args_base");
+    exactSenderSPField = type.getAddressField("_exact_sender_sp");
+    senderPCField      = type.getAddressField("_sender_pc");
+  }
+
+  private static AddressField senderLinkField;
+  private static AddressField savedArgsBaseField;
+  private static AddressField exactSenderSPField;
+  private static AddressField senderPCField;
+
+  static X86RicochetFrame fromFrame(X86Frame f) {
+    return new X86RicochetFrame(f.getFP().addOffsetTo(- senderLinkField.getOffset()));
+  }
+
+  private X86RicochetFrame(Address addr) {
+    super(addr);
+  }
+
+  public Address senderLink() {
+    return senderLinkField.getValue(addr);
+  }
+  public Address senderLinkAddress() {
+    return addr.addOffsetTo(senderLinkField.getOffset());
+  }
+  public Address savedArgsBase() {
+    return savedArgsBaseField.getValue(addr);
+  }
+  public Address extendedSenderSP() {
+    return savedArgsBase();
+  }
+  public Address exactSenderSP() {
+    return exactSenderSPField.getValue(addr);
+  }
+  public Address senderPC() {
+    return senderPCField.getValue(addr);
+  }
+}