/***********************************************************************/
/*                                                                     */
/*                           Objective Caml                            */
/*                                                                     */
/*             Damien Doligez, projet Para, INRIA Rocquencourt         */
/*                                                                     */
/*  Copyright 1996 Institut National de Recherche en Informatique et   */
/*  en Automatique.  All rights reserved.  This file is distributed    */
/*  under the terms of the GNU Library General Public License.         */
/*                                                                     */
/***********************************************************************/

/***---------------------------------------------------------------------
  Modified and adapted for the Lazy Virtual Machine by Daan Leijen.
  Modifications copyright 2001, Daan Leijen. This (modified) file is
  distributed under the terms of the GNU Library General Public License.
---------------------------------------------------------------------***/

/* $Id$ */

#ifndef _gc_
#define _gc_

#include "mlvalues.h"

#define Caml_white (0 << 8)
#define Caml_gray  (1 << 8)
#define Caml_blue  (2 << 8)
#define Caml_black (3 << 8)

#define Color_hd(hd) ((color_t) ((hd) & Caml_black))
#define Color_hp(hp) Color_hd (Hd_hp (hp))

#define Is_white_hd(hd) (Color_hd (hd) == Caml_white)
#define Is_gray_hd(hd) (Color_hd (hd) == Caml_gray)
#define Is_blue_hd(hd) (Color_hd (hd) == Caml_blue)
#define Is_black_hd(hd) (Color_hd (hd) == Caml_black)

#define Whitehd_hd(hd) (((hd)  & ~Caml_black)/*| Caml_white*/)
#define Grayhd_hd(hd)  (((hd)  & ~Caml_black)  | Caml_gray)
#define Blackhd_hd(hd) (((hd)/*& ~Caml_black*/)| Caml_black)
#define Bluehd_hd(hd)  (((hd)  & ~Caml_black)  | Caml_blue)

/* This depends on the layout of the header.  See [mlvalues.h]. */
#define Make_header(wosize, tag, color)                                       \
       ((header_t) (((header_t) (wosize) << 10)                               \
                    + (color)                                                 \
                    + (tag_t) (tag)))

#define Color_val(val) (Color_hd (Hd_val (val)))

#define Is_white_val(val) (Color_val(val) == Caml_white)
#define Is_gray_val(val) (Color_val(val) == Caml_gray)
#define Is_blue_val(val) (Color_val(val) == Caml_blue)
#define Is_black_val(val) (Color_val(val) == Caml_black)


#endif /* _gc_ */