1/*-
2 * Copyright (c) 1992, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This software was developed by the Computer Systems Engineering group
6 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7 * contributed to Berkeley.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	@(#)quad.h	8.1 (Berkeley) 6/4/93
34 * $FreeBSD$
35 */
36
37/*
38 * Quad arithmetic.
39 *
40 * This library makes the following assumptions:
41 *
42 *  - The type long long (aka quad_t) exists.
43 *
44 *  - A quad variable is exactly twice as long as `long'.
45 *
46 *  - The machine's arithmetic is two's complement.
47 *
48 * This library can provide 128-bit arithmetic on a machine with 128-bit
49 * quads and 64-bit longs, for instance, or 96-bit arithmetic on machines
50 * with 48-bit longs.
51 */
52
53#include <sys/cdefs.h>
54#include <sys/types.h>
55#include <limits.h>
56
57/*
58 * Depending on the desired operation, we view a `long long' (aka quad_t) in
59 * one or more of the following formats.
60 */
61union uu {
62	quad_t	q;		/* as a (signed) quad */
63	quad_t	uq;		/* as an unsigned quad */
64	long	sl[2];		/* as two signed longs */
65	u_long	ul[2];		/* as two unsigned longs */
66};
67
68/*
69 * Define high and low longwords.
70 */
71#define	H		_QUAD_HIGHWORD
72#define	L		_QUAD_LOWWORD
73
74/*
75 * Total number of bits in a quad_t and in the pieces that make it up.
76 * These are used for shifting, and also below for halfword extraction
77 * and assembly.
78 */
79#define	QUAD_BITS	(sizeof(quad_t) * CHAR_BIT)
80#define	LONG_BITS	(sizeof(long) * CHAR_BIT)
81#define	HALF_BITS	(sizeof(long) * CHAR_BIT / 2)
82
83/*
84 * Extract high and low shortwords from longword, and move low shortword of
85 * longword to upper half of long, i.e., produce the upper longword of
86 * ((quad_t)(x) << (number_of_bits_in_long/2)).  (`x' must actually be u_long.)
87 *
88 * These are used in the multiply code, to split a longword into upper
89 * and lower halves, and to reassemble a product as a quad_t, shifted left
90 * (sizeof(long)*CHAR_BIT/2).
91 */
92#define	HHALF(x)	((x) >> HALF_BITS)
93#define	LHALF(x)	((x) & ((1 << HALF_BITS) - 1))
94#define	LHUP(x)		((x) << HALF_BITS)
95
96quad_t		__divdi3(quad_t a, quad_t b);
97quad_t		__moddi3(quad_t a, quad_t b);
98u_quad_t	__qdivrem(u_quad_t u, u_quad_t v, u_quad_t *rem);
99u_quad_t	__udivdi3(u_quad_t a, u_quad_t b);
100u_quad_t	__umoddi3(u_quad_t a, u_quad_t b);
101
102/*
103 * XXX
104 * Compensate for gcc 1 vs gcc 2.  Gcc 1 defines ?sh?di3's second argument
105 * as u_quad_t, while gcc 2 correctly uses int.  Unfortunately, we still use
106 * both compilers.
107 */
108#if __GNUC__ >= 2
109typedef unsigned int	qshift_t;
110#else
111typedef u_quad_t	qshift_t;
112#endif
113