xref: /netbsd/lib/libm/src/s_copysignl.c (revision 6550d01e)
1 /*	$NetBSD: s_copysignl.c,v 1.2 2010/09/17 20:39:39 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2010 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 #include <sys/cdefs.h>
29 __RCSID("$NetBSD: s_copysignl.c,v 1.2 2010/09/17 20:39:39 christos Exp $");
30 
31 #include <math.h>
32 #include <machine/ieee.h>
33 
34 /*
35  * copysignl(long double x, long double y)
36  * This function returns a value with the magnitude of x and the sign of y.
37  */
38 #ifdef EXT_EXP_INFNAN
39 long double
40 copysignl(long double x, long double y)
41 {
42 	union ieee_ext_u ux, uy;
43 
44 	ux.extu_ld = x;
45 	uy.extu_ld = y;
46 
47 	ux.extu_ext.ext_sign = uy.extu_ext.ext_sign;
48 
49 	return (ux.extu_ld);
50 }
51 #endif
52