*** old/src/cpu/x86/vm/frame_x86.inline.hpp	Wed Oct 28 19:51:07 2009
--- new/src/cpu/x86/vm/frame_x86.inline.hpp	Wed Oct 28 19:51:07 2009

*** 223,237 ****
--- 223,238 ----
  }
  
  // top of expression stack
  inline intptr_t* frame::interpreter_frame_tos_address() const {
    intptr_t* last_sp = interpreter_frame_last_sp();
-   if (last_sp == NULL ) {
      return sp();
    } else {
!     // sp() may have been extended or shrunk by an adapter.  At least
      assert(last_sp < fp() && last_sp >= sp(), "bad tos");
+     // check that we don't fall behind the legal region.
+     assert(last_sp < (intptr_t*) interpreter_frame_monitor_begin(), "bad tos");
      return last_sp;
    }
  }
  
  #endif /* CC_INTERP */