xref: /freebsd/lib/msun/src/s_isnan.c (revision eb69d1f144a6fcc765d1b9d44a5ae8082353e70b)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #include <math.h>
32 
33 #include "fpmath.h"
34 
35 /* Provided by libc.so */
36 #ifndef PIC
37 #undef isnan
38 int
39 isnan(double d)
40 {
41 	union IEEEd2bits u;
42 
43 	u.d = d;
44 	return (u.bits.exp == 2047 && (u.bits.manl != 0 || u.bits.manh != 0));
45 }
46 #endif /* !PIC */
47 
48 int
49 __isnanf(float f)
50 {
51 	union IEEEf2bits u;
52 
53 	u.f = f;
54 	return (u.bits.exp == 255 && u.bits.man != 0);
55 }
56 
57 int
58 __isnanl(long double e)
59 {
60 	union IEEEl2bits u;
61 
62 	u.e = e;
63 	mask_nbit_l(u);
64 	return (u.bits.exp == 32767 && (u.bits.manl != 0 || u.bits.manh != 0));
65 }
66 
67 __weak_reference(__isnanf, isnanf);
68