--- old/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.inline.hpp	2009-08-01 04:11:14.235841199 +0100
+++ new/hotspot/src/share/vm/gc_implementation/parallelScavenge/psScavenge.inline.hpp	2009-08-01 04:11:14.163666806 +0100
@@ -2,7 +2,7 @@
 #pragma ident "@(#)psScavenge.inline.hpp	1.18 07/05/05 17:05:29 JVM"
 #endif
 /*
- * Copyright 2002-2006 Sun Microsystems, Inc.  All Rights Reserved.
+ * Copyright 2002-2008 Sun Microsystems, Inc.  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
@@ -25,28 +25,33 @@
  *  
  */
 
-
 inline void PSScavenge::save_to_space_top_before_gc() {
   ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
   _to_space_top_before_gc = heap->young_gen()->to_space()->top();
 }
 
-inline bool PSScavenge::should_scavenge(oop p) {
-  return p == NULL ? false : PSScavenge::is_obj_in_young((HeapWord*) p);
+template <class T> inline bool PSScavenge::should_scavenge(T* p) {
+  T heap_oop = oopDesc::load_heap_oop(p);
+  if (oopDesc::is_null(heap_oop)) return false;
+  oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
+  return PSScavenge::is_obj_in_young((HeapWord*)obj);
 }
 
-inline bool PSScavenge::should_scavenge(oop p, MutableSpace* to_space) {
+template <class T>
+inline bool PSScavenge::should_scavenge(T* p, MutableSpace* to_space) {
   if (should_scavenge(p)) {
+    oop obj = oopDesc::load_decode_heap_oop_not_null(p);
     // Skip objects copied to to_space since the scavenge started.
-    HeapWord* const addr = (HeapWord*) p;
+    HeapWord* const addr = (HeapWord*)obj;
     return addr < to_space_top_before_gc() || addr >= to_space->end();
   }
   return false;
 }
 
-inline bool PSScavenge::should_scavenge(oop p, bool check_to_space) {
+template <class T>
+inline bool PSScavenge::should_scavenge(T* p, bool check_to_space) {
   if (check_to_space) {
-    ParallelScavengeHeap* heap = (ParallelScavengeHeap*) Universe::heap();
+    ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
     return should_scavenge(p, heap->young_gen()->to_space());
   }
   return should_scavenge(p);
@@ -55,24 +60,23 @@
 // Attempt to "claim" oop at p via CAS, push the new obj if successful
 // This version tests the oop* to make sure it is within the heap before
 // attempting marking.
+template <class T>
 inline void PSScavenge::copy_and_push_safe_barrier(PSPromotionManager* pm,
-                                                   oop*                p) {
-  assert(should_scavenge(*p, true), "revisiting object?");
+                                                   T*                  p) {
+  assert(should_scavenge(p, true), "revisiting object?");
 
-  oop o = *p;
-  if (o->is_forwarded()) {
-    *p = o->forwardee();
-  } else {
-    *p = pm->copy_to_survivor_space(o, pm->depth_first());
-  }
-  
-  // We cannot mark without test, as some code passes us pointers 
+  oop o = oopDesc::load_decode_heap_oop_not_null(p);
+  oop new_obj = o->is_forwarded()
+        ? o->forwardee()
+        : pm->copy_to_survivor_space(o, pm->depth_first());
+  oopDesc::encode_store_heap_oop_not_null(p, new_obj);
+
+  // We cannot mark without test, as some code passes us pointers
   // that are outside the heap.
-  if ((!PSScavenge::is_obj_in_young((HeapWord*) p)) &&
+  if ((!PSScavenge::is_obj_in_young((HeapWord*)p)) &&
       Universe::heap()->is_in_reserved(p)) {
-    o = *p;
-    if (PSScavenge::is_obj_in_young((HeapWord*) o)) {
-      card_table()->inline_write_ref_field_gc(p, o);
+    if (PSScavenge::is_obj_in_young((HeapWord*)new_obj)) {
+      card_table()->inline_write_ref_field_gc(p, new_obj);
     }
   }
 }