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: stable/10/lib/libc/gen/isnan.c 354596 2019-11-10 17:33:10Z dim $
27 */
28
29#include <math.h>
30
31#include "fpmath.h"
32
33/*
34 * XXX These routines belong in libm, but they must remain in libc for
35 *     binary compat until we can bump libm's major version number.
36 *
37 * Note this only applies to the dynamic versions of libm and libc, so
38 * for the static and profiled versions we stub out the definitions.
39 * Otherwise you cannot link statically to libm and libc at the same
40 * time, when calling both functions.
41 */
42
43#ifdef PIC
44/*
45 * Because math.h defines __isnan and __isnanf as aliases for compatibility with
46 * glibc and CUDA, we have to undefine them here to avoid redefinition errors.
47 */
48#undef __isnan
49#undef __isnanf
50
51__weak_reference(__isnan, isnan);
52__weak_reference(__isnanf, isnanf);
53
54int
55__isnan(double d)
56{
57	union IEEEd2bits u;
58
59	u.d = d;
60	return (u.bits.exp == 2047 && (u.bits.manl != 0 || u.bits.manh != 0));
61}
62
63int
64__isnanf(float f)
65{
66	union IEEEf2bits u;
67
68	u.f = f;
69	return (u.bits.exp == 255 && u.bits.man != 0);
70}
71#endif /* PIC */
72