quad.h revision 1.9 
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 * 3. 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 *	$OpenBSD: quad.h,v 1.9 2004/11/28 07:23:41 mickey Exp $
34 */
35
36/*
37 * Quad arithmetic.
38 *
39 * This library makes the following assumptions:
40 *
41 *  - The type long long (aka quad_t) exists.
42 *
43 *  - A quad variable is exactly twice as long as `int'.
44 *
45 *  - The machine's arithmetic is two's complement.
46 *
47 * This library can provide 128-bit arithmetic on a machine with 128-bit
48 * quads and 64-bit ints, for instance, or 96-bit arithmetic on machines
49 * with 48-bit ints.
50 */
51
52#include <sys/types.h>
53#if !defined(_KERNEL) && !defined(_STANDALONE)
54#include <limits.h>
55#else
56#include <sys/limits.h>
57#endif
58
59/*
60 * Depending on the desired operation, we view a `long long' (aka quad_t) in
61 * one or more of the following formats.
62 */
63union uu {
64	quad_t	q;		/* as a (signed) quad */
65	u_quad_t uq;		/* as an unsigned quad */
66	int	sl[2];		/* as two signed ints */
67	u_int	ul[2];		/* as two unsigned ints */
68};
69
70/*
71 * Define high and low parts of a quad_t.
72 */
73#define	H		_QUAD_HIGHWORD
74#define	L		_QUAD_LOWWORD
75
76/*
77 * Total number of bits in a quad_t and in the pieces that make it up.
78 * These are used for shifting, and also below for halfword extraction
79 * and assembly.
80 */
81#define	QUAD_BITS	(sizeof(quad_t) * CHAR_BIT)
82#define	INT_BITS	(sizeof(int) * CHAR_BIT)
83#define	HALF_BITS	(sizeof(int) * CHAR_BIT / 2)
84
85/*
86 * Extract high and low shortwords from longword, and move low shortword of
87 * longword to upper half of long, i.e., produce the upper longword of
88 * ((quad_t)(x) << (number_of_bits_in_int/2)).  (`x' must actually be u_int.)
89 *
90 * These are used in the multiply code, to split a longword into upper
91 * and lower halves, and to reassemble a product as a quad_t, shifted left
92 * (sizeof(int)*CHAR_BIT/2).
93 */
94#define	HHALF(x)	((u_int)(x) >> HALF_BITS)
95#define	LHALF(x)	((u_int)(x) & (((int)1 << HALF_BITS) - 1))
96#define	LHUP(x)		((u_int)(x) << HALF_BITS)
97
98/*
99 * XXX
100 * Compensate for gcc 1 vs gcc 2.  Gcc 1 defines ?sh?di3's second argument
101 * as u_quad_t, while gcc 2 correctly uses int.  Unfortunately, we still use
102 * both compilers.
103 */
104#if __GNUC_PREREQ__(2, 0) || defined(lint)
105typedef unsigned int	qshift_t;
106#else
107typedef u_quad_t	qshift_t;
108#endif
109
110quad_t __adddi3(quad_t, quad_t);
111quad_t __anddi3(quad_t, quad_t);
112quad_t __ashldi3(quad_t, qshift_t);
113quad_t __ashrdi3(quad_t, qshift_t);
114int __cmpdi2(quad_t, quad_t);
115quad_t __divdi3(quad_t, quad_t);
116quad_t __fixdfdi(double);
117quad_t __fixsfdi(float);
118u_quad_t __fixunsdfdi(double);
119u_quad_t __fixunssfdi(float);
120double __floatdidf(quad_t);
121float __floatdisf(quad_t);
122double __floatunsdidf(u_quad_t);
123quad_t __iordi3(quad_t, quad_t);
124quad_t __lshldi3(quad_t, qshift_t);
125quad_t __lshrdi3(quad_t, qshift_t);
126quad_t __moddi3(quad_t, quad_t);
127quad_t __muldi3(quad_t, quad_t);
128quad_t __negdi2(quad_t);
129quad_t __one_cmpldi2(quad_t);
130u_quad_t __qdivrem(u_quad_t, u_quad_t, u_quad_t *);
131quad_t __subdi3(quad_t, quad_t);
132int __ucmpdi2(u_quad_t, u_quad_t);
133u_quad_t __udivdi3(u_quad_t, u_quad_t );
134u_quad_t __umoddi3(u_quad_t, u_quad_t );
135quad_t __xordi3(quad_t, quad_t);
136