dc-regdef.h   [plain text]


/* 
 * definitions for dc's "register" declarations
 *
 * Copyright (C) 1994 Free Software Foundation, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you can either send email to this
 * program's author (see below) or write to:
 *
 *    The Free Software Foundation, Inc.
 *    59 Temple Place, Suite 330
 *    Boston, MA 02111 USA
 */

#ifdef HAVE_LIMITS_H
# include <limits.h>	/* UCHAR_MAX */
#endif

/* determine how many register stacks there are */
#ifndef DC_REGCOUNT
# ifndef UCHAR_MAX
#  define DC_REGCOUNT 256
# else
#  define DC_REGCOUNT (UCHAR_MAX+1)
# endif
#endif /* not DC_REGCOUNT */

/* efficiency hack for masking arbritrary integers to 0..(DC_REGCOUNT-1) */
#if (DC_REGCOUNT & (DC_REGCOUNT-1)) == 0	/* DC_REGCOUNT is power of 2 */
# define regmap(r)	((r) & (DC_REGCOUNT-1))
#else
# define regmap(r)	((r) % DC_REGCOUNT)
#endif