1 /* @(#)s_copysign.c 5.1 93/09/24 */
2 /*
3 * ====================================================
4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
5 *
6 * Developed at SunPro, a Sun Microsystems, Inc. business.
7 * Permission to use, copy, modify, and distribute this
8 * software is freely granted, provided that this notice
9 * is preserved.
10 * ====================================================
11 */
12
13 #include <sys/cdefs.h>
14 #if defined(LIBM_SCCS) && !defined(lint)
15 __RCSID("$NetBSD: s_copysign.c,v 1.13 2015/05/14 19:26:12 joerg Exp $");
16 #endif
17
18 /*
19 * copysign(double x, double y)
20 * copysign(x,y) returns a value with the magnitude of x and
21 * with the sign bit of y.
22 */
23
24 #include "math.h"
25 #include "math_private.h"
26
27 #if !defined(__HAVE_LONG_DOUBLE) && !defined(__HAVE_IBM_LONGDOUBLE)
__strong_alias(_copysignl,copysign)28 __strong_alias(_copysignl, copysign)
29 __weak_alias(copysignl, copysign)
30 #endif
31
32 double
33 copysign(double x, double y)
34 {
35 u_int32_t hx,hy;
36 GET_HIGH_WORD(hx,x);
37 GET_HIGH_WORD(hy,y);
38 SET_HIGH_WORD(x,(hx&0x7fffffff)|(hy&0x80000000));
39 return x;
40 }
41