xref: /openbsd-src/sys/lib/libkern/moddi3.c (revision a4afd6dad3fba28f80e70208181c06c482259988)
1 /*	$NetBSD: moddi3.c,v 1.5 1995/10/07 09:26:31 mycroft Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This software was developed by the Computer Systems Engineering group
8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
9  * contributed to Berkeley.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  */
39 
40 #if defined(LIBC_SCCS) && !defined(lint)
41 #if 0
42 static char sccsid[] = "@(#)moddi3.c	8.1 (Berkeley) 6/4/93";
43 #else
44 static char rcsid[] = "$NetBSD: moddi3.c,v 1.5 1995/10/07 09:26:31 mycroft Exp $";
45 #endif
46 #endif /* LIBC_SCCS and not lint */
47 
48 #include "quad.h"
49 
50 /*
51  * Return remainder after dividing two signed quads.
52  *
53  * XXX
54  * If -1/2 should produce -1 on this machine, this code is wrong.
55  */
56 quad_t
57 __moddi3(a, b)
58 	quad_t a, b;
59 {
60 	u_quad_t ua, ub, ur;
61 	int neg;
62 
63 	if (a < 0)
64 		ua = -(u_quad_t)a, neg = 1;
65 	else
66 		ua = a, neg = 0;
67 	if (b < 0)
68 		ub = -(u_quad_t)b, neg ^= 1;
69 	else
70 		ub = b;
71 	(void)__qdivrem(ua, ub, &ur);
72 	return (neg ? -ur : ur);
73 }
74