1/*
2 * definitions for dc's "register" declarations
3 *
4 * Copyright (C) 1994 Free Software Foundation, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2, or (at your option)
9 * any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, you can either send email to this
18 * program's author (see below) or write to:
19 *
20 *    The Free Software Foundation, Inc.
21 *    59 Temple Place, Suite 330
22 *    Boston, MA 02111 USA
23 */
24
25#ifdef HAVE_LIMITS_H
26# include <limits.h>	/* UCHAR_MAX */
27#endif
28
29/* determine how many register stacks there are */
30#ifndef DC_REGCOUNT
31# ifndef UCHAR_MAX
32#  define DC_REGCOUNT 256
33# else
34#  define DC_REGCOUNT (UCHAR_MAX+1)
35# endif
36#endif /* not DC_REGCOUNT */
37
38/* efficiency hack for masking arbritrary integers to 0..(DC_REGCOUNT-1) */
39#if (DC_REGCOUNT & (DC_REGCOUNT-1)) == 0	/* DC_REGCOUNT is power of 2 */
40# define regmap(r)	((r) & (DC_REGCOUNT-1))
41#else
42# define regmap(r)	((r) % DC_REGCOUNT)
43#endif
44