1*e55db843SJesús Blázquez /*
2*e55db843SJesús Blázquez * SPDX-License-Identifier: BSD-2-Clause
3*e55db843SJesús Blázquez *
4*e55db843SJesús Blázquez * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
5*e55db843SJesús Blázquez * Copyright (c) 2026 Jesús Blázquez <jesuscblazquez@gmail.com>
6*e55db843SJesús Blázquez * All rights reserved.
7*e55db843SJesús Blázquez *
8*e55db843SJesús Blázquez * Redistribution and use in source and binary forms, with or without
9*e55db843SJesús Blázquez * modification, are permitted provided that the following conditions
10*e55db843SJesús Blázquez * are met:
11*e55db843SJesús Blázquez * 1. Redistributions of source code must retain the above copyright
12*e55db843SJesús Blázquez * notice, this list of conditions and the following disclaimer.
13*e55db843SJesús Blázquez * 2. Redistributions in binary form must reproduce the above copyright
14*e55db843SJesús Blázquez * notice, this list of conditions and the following disclaimer in the
15*e55db843SJesús Blázquez * documentation and/or other materials provided with the distribution.
16*e55db843SJesús Blázquez *
17*e55db843SJesús Blázquez * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18*e55db843SJesús Blázquez * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19*e55db843SJesús Blázquez * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20*e55db843SJesús Blázquez * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21*e55db843SJesús Blázquez * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22*e55db843SJesús Blázquez * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23*e55db843SJesús Blázquez * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24*e55db843SJesús Blázquez * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25*e55db843SJesús Blázquez * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26*e55db843SJesús Blázquez * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27*e55db843SJesús Blázquez * SUCH DAMAGE.
28*e55db843SJesús Blázquez */
29*e55db843SJesús Blázquez
30*e55db843SJesús Blázquez #include <float.h>
31*e55db843SJesús Blázquez #include <math.h>
32*e55db843SJesús Blázquez
33*e55db843SJesús Blázquez #include "fpmath.h"
34*e55db843SJesús Blázquez
35*e55db843SJesús Blázquez #ifdef USE_BUILTIN_FMAXIMUM
36*e55db843SJesús Blázquez double
fmaximum(double x,double y)37*e55db843SJesús Blázquez fmaximum(double x, double y)
38*e55db843SJesús Blázquez {
39*e55db843SJesús Blázquez return (__builtin_fmaximum(x, y));
40*e55db843SJesús Blázquez }
41*e55db843SJesús Blázquez #else
42*e55db843SJesús Blázquez double
fmaximum(double x,double y)43*e55db843SJesús Blázquez fmaximum(double x, double y)
44*e55db843SJesús Blázquez {
45*e55db843SJesús Blázquez union IEEEd2bits u[2];
46*e55db843SJesús Blázquez
47*e55db843SJesús Blázquez u[0].d = x;
48*e55db843SJesús Blázquez u[1].d = y;
49*e55db843SJesús Blázquez
50*e55db843SJesús Blázquez /* Handle NaN according to ISO/IEC 60559. NaN argument -> NaN return */
51*e55db843SJesús Blázquez if ((u[0].bits.exp == 2047 && (u[0].bits.manh | u[0].bits.manl) != 0) ||
52*e55db843SJesús Blázquez (u[1].bits.exp == 2047 && (u[1].bits.manh | u[1].bits.manl) != 0))
53*e55db843SJesús Blázquez return (NAN);
54*e55db843SJesús Blázquez
55*e55db843SJesús Blázquez /* Handle comparisons of signed zeroes. */
56*e55db843SJesús Blázquez if (u[0].bits.sign != u[1].bits.sign)
57*e55db843SJesús Blázquez return (u[u[0].bits.sign].d);
58*e55db843SJesús Blázquez
59*e55db843SJesús Blázquez return (x > y ? x : y);
60*e55db843SJesús Blázquez }
61*e55db843SJesús Blázquez #endif
62*e55db843SJesús Blázquez
63*e55db843SJesús Blázquez #if (LDBL_MANT_DIG == 53)
64*e55db843SJesús Blázquez __weak_reference(fmaximum, fmaximuml);
65*e55db843SJesús Blázquez #endif
66