diff -r dbf1a1c172d6 -r 803947e176bd hotspot/src/share/vm/oops/oop.hpp
--- a/hotspot/src/share/vm/oops/oop.hpp	Wed May 28 12:42:34 2008 -0700
+++ b/hotspot/src/share/vm/oops/oop.hpp	Wed May 28 21:06:24 2008 -0700
@@ -77,10 +77,15 @@
   void init_mark();
 
   klassOop klass() const;
+  klassOop klass_or_null() const volatile;
   oop* klass_addr();
   narrowOop* compressed_klass_addr();
 
   void set_klass(klassOop k);
+
+  // For klass field compression
+  int klass_gap() const;
+  void set_klass_gap(int z);
   // For when the klass pointer is being used as a linked list "next" field.
   void set_klass_to_list_ptr(oop k);