xref: /freebsd/lib/msun/src/s_isnan.c (revision 59e2ff550c448126b988150ce800cdf73bb5103e)
1 /*-
2  * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include <math.h>
30 
31 #include "fpmath.h"
32 
33 /* Provided by libc.so */
34 #ifndef PIC
35 #undef isnan
36 int
37 isnan(double d)
38 {
39 	union IEEEd2bits u;
40 
41 	u.d = d;
42 	return (u.bits.exp == 2047 && (u.bits.manl != 0 || u.bits.manh != 0));
43 }
44 #endif /* !PIC */
45 
46 int
47 __isnanf(float f)
48 {
49 	union IEEEf2bits u;
50 
51 	u.f = f;
52 	return (u.bits.exp == 255 && u.bits.man != 0);
53 }
54 
55 int
56 __isnanl(long double e)
57 {
58 	union IEEEl2bits u;
59 
60 	u.e = e;
61 	mask_nbit_l(u);
62 	return (u.bits.exp == 32767 && (u.bits.manl != 0 || u.bits.manh != 0));
63 }
64 
65 __weak_reference(__isnanf, isnanf);
66