xref: /freebsd/lib/msun/src/s_fminimum_num.c (revision 4e30c12973c73539bef01be3870a90b6346141e8)
1*4e30c129SJesús Blázquez /*
2*4e30c129SJesús Blázquez  * SPDX-License-Identifier: BSD-2-Clause
3*4e30c129SJesús Blázquez  *
4*4e30c129SJesús Blázquez  * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
5*4e30c129SJesús Blázquez  * Copyright (c) 2026 Jesús Blázquez <jesuscblazquez@gmail.com>
6*4e30c129SJesús Blázquez  * All rights reserved.
7*4e30c129SJesús Blázquez  *
8*4e30c129SJesús Blázquez  * Redistribution and use in source and binary forms, with or without
9*4e30c129SJesús Blázquez  * modification, are permitted provided that the following conditions
10*4e30c129SJesús Blázquez  * are met:
11*4e30c129SJesús Blázquez  * 1. Redistributions of source code must retain the above copyright
12*4e30c129SJesús Blázquez  *    notice, this list of conditions and the following disclaimer.
13*4e30c129SJesús Blázquez  * 2. Redistributions in binary form must reproduce the above copyright
14*4e30c129SJesús Blázquez  *    notice, this list of conditions and the following disclaimer in the
15*4e30c129SJesús Blázquez  *    documentation and/or other materials provided with the distribution.
16*4e30c129SJesús Blázquez  *
17*4e30c129SJesús Blázquez  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18*4e30c129SJesús Blázquez  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19*4e30c129SJesús Blázquez  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20*4e30c129SJesús Blázquez  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21*4e30c129SJesús Blázquez  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22*4e30c129SJesús Blázquez  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23*4e30c129SJesús Blázquez  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24*4e30c129SJesús Blázquez  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25*4e30c129SJesús Blázquez  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26*4e30c129SJesús Blázquez  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27*4e30c129SJesús Blázquez  * SUCH DAMAGE.
28*4e30c129SJesús Blázquez  */
29*4e30c129SJesús Blázquez 
30*4e30c129SJesús Blázquez #include <float.h>
31*4e30c129SJesús Blázquez #include <math.h>
32*4e30c129SJesús Blázquez #include <stdbool.h>
33*4e30c129SJesús Blázquez 
34*4e30c129SJesús Blázquez #include "fpmath.h"
35*4e30c129SJesús Blázquez 
36*4e30c129SJesús Blázquez #ifdef USE_BUILTIN_FMINIMUM_NUM
37*4e30c129SJesús Blázquez double
fminimum_num(double x,double y)38*4e30c129SJesús Blázquez fminimum_num(double x, double y)
39*4e30c129SJesús Blázquez {
40*4e30c129SJesús Blázquez 	return (__builtin_fminimum_num(x, y));
41*4e30c129SJesús Blázquez }
42*4e30c129SJesús Blázquez #else
43*4e30c129SJesús Blázquez double
fminimum_num(double x,double y)44*4e30c129SJesús Blázquez fminimum_num(double x, double y)
45*4e30c129SJesús Blázquez {
46*4e30c129SJesús Blázquez 	union IEEEd2bits u[2];
47*4e30c129SJesús Blázquez 	bool nan_x, nan_y;
48*4e30c129SJesús Blázquez 
49*4e30c129SJesús Blázquez 	u[0].d = x;
50*4e30c129SJesús Blázquez 	u[1].d = y;
51*4e30c129SJesús Blázquez 
52*4e30c129SJesús Blázquez 	nan_x = u[0].bits.exp == 2047 && (u[0].bits.manh | u[0].bits.manl) != 0;
53*4e30c129SJesús Blázquez 	nan_y = u[1].bits.exp == 2047 && (u[1].bits.manh | u[1].bits.manl) != 0;
54*4e30c129SJesús Blázquez 
55*4e30c129SJesús Blázquez 	if (nan_x || nan_y) {
56*4e30c129SJesús Blázquez 		/* These ternary conditionals force (x+y), so that sNaN's raise exceptions */
57*4e30c129SJesús Blázquez 		if (nan_x && nan_y)
58*4e30c129SJesús Blázquez 			return (x + y);
59*4e30c129SJesús Blázquez 		if (nan_x)
60*4e30c129SJesús Blázquez 			return ((x + y) != 0.0 ? y : y);
61*4e30c129SJesús Blázquez 		return ((x + y) != 0.0 ? x : x);
62*4e30c129SJesús Blázquez 	}
63*4e30c129SJesús Blázquez 
64*4e30c129SJesús Blázquez 	/* Handle comparisons of signed zeroes. */
65*4e30c129SJesús Blázquez 	if (u[0].bits.sign != u[1].bits.sign)
66*4e30c129SJesús Blázquez 		return (u[u[1].bits.sign].d);
67*4e30c129SJesús Blázquez 
68*4e30c129SJesús Blázquez 	return (x < y ? x : y);
69*4e30c129SJesús Blázquez }
70*4e30c129SJesús Blázquez #endif
71*4e30c129SJesús Blázquez 
72*4e30c129SJesús Blázquez #if (LDBL_MANT_DIG == 53)
73*4e30c129SJesús Blázquez __weak_reference(fminimum_num, fminimum_numl);
74*4e30c129SJesús Blázquez #endif
75*4e30c129SJesús Blázquez 
76*4e30c129SJesús Blázquez 
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