--- old/hotspot/src/cpu/zero/vm/javaFrameAnchor_zero.hpp	2010-04-20 09:28:32.000000000 +0100
+++ new/hotspot/src/cpu/zero/vm/javaFrameAnchor_zero.hpp	2010-04-20 09:28:32.000000000 +0100
@@ -1,6 +1,6 @@
 /*
  * Copyright 2003-2005 Sun Microsystems, Inc.  All Rights Reserved.
- * Copyright 2007, 2008 Red Hat, Inc.
+ * Copyright 2007, 2008, 2010 Red Hat, Inc.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -23,21 +23,31 @@
  *
  */
 
+ private:
+  ZeroFrame* volatile _last_Java_fp;
+
  public:
   // Each arch must define reset, save, restore
   // These are used by objects that only care about:
   //  1 - initializing a new state (thread creation, javaCalls)
   //  2 - saving a current state (javaCalls)
   //  3 - restoring an old state (javaCalls)
+  // Note that whenever _last_Java_sp != NULL other anchor fields
+  // must be valid.  The profiler apparently depends on this.
 
   void clear() {
     // clearing _last_Java_sp must be first
     _last_Java_sp = NULL;
     // fence?
+    _last_Java_fp = NULL;
     _last_Java_pc = NULL;
   }
 
   void copy(JavaFrameAnchor* src) {
+    set(src->_last_Java_sp, src->_last_Java_pc, src->_last_Java_fp);
+  }
+
+  void set(intptr_t* sp, address pc, ZeroFrame* fp) {
     // In order to make sure the transition state is valid for "this"
     // We must clear _last_Java_sp before copying the rest of the new
     // data
@@ -46,13 +56,14 @@
     // previous version (pd_cache_state) don't NULL _last_Java_sp
     // unless the value is changing
     //
-    if (_last_Java_sp != src->_last_Java_sp)
+    if (_last_Java_sp != sp)
       _last_Java_sp = NULL;
 
-    _last_Java_pc = src->_last_Java_pc;
+    _last_Java_fp = fp;
+    _last_Java_pc = pc;
     // Must be last so profiler will always see valid frame if
     // has_last_frame() is true
-    _last_Java_sp = src->_last_Java_sp;
+    _last_Java_sp = sp;
   }
 
   bool walkable() {
@@ -67,6 +78,6 @@
     return _last_Java_sp;
   }
 
-  void set_last_Java_sp(intptr_t* sp) {
-    _last_Java_sp = sp;
+  ZeroFrame* last_Java_fp() const {
+    return _last_Java_fp;
   }