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
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD: head/lib/msun/src/s_fmax.c 326219 2017-11-26 02:00:33Z pfg $");
31
32 #include <float.h>
33 #include <math.h>
34
35 #include "fpmath.h"
36
37 double
fmax(double x,double y)38 fmax(double x, double y)
39 {
40 union IEEEd2bits u[2];
41
42 u[0].d = x;
43 u[1].d = y;
44
45 /* Check for NaNs to avoid raising spurious exceptions. */
46 if (u[0].bits.exp == 2047 && (u[0].bits.manh | u[0].bits.manl) != 0)
47 return (y);
48 if (u[1].bits.exp == 2047 && (u[1].bits.manh | u[1].bits.manl) != 0)
49 return (x);
50
51 /* Handle comparisons of signed zeroes. */
52 if (u[0].bits.sign != u[1].bits.sign)
53 return (u[u[0].bits.sign].d);
54
55 return (x > y ? x : y);
56 }
57
58 #if (LDBL_MANT_DIG == 53)
59 __weak_reference(fmax, fmaxl);
60 #endif
61