xref: /freebsd/lib/msun/src/s_fminimum_numf.c (revision 4e30c12973c73539bef01be3870a90b6346141e8)
1 /*
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2004 David Schultz <das@FreeBSD.ORG>
5  * Copyright (c) 2026 Jesús Blázquez <jesuscblazquez@gmail.com>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <math.h>
31 #include <stdbool.h>
32 
33 #include "fpmath.h"
34 
35 #ifdef USE_BUILTIN_FMINIMUM_NUMF
36 float
fminimum_numf(float x,float y)37 fminimum_numf(float x, float y)
38 {
39 	return (__builtin_fminimum_numf(x, y));
40 }
41 #else
42 float
fminimum_numf(float x,float y)43 fminimum_numf(float x, float y)
44 {
45 	union IEEEf2bits u[2];
46 	bool nan_x, nan_y;
47 
48 	u[0].f = x;
49 	u[1].f = y;
50 
51 	nan_x = u[0].bits.exp == 255 && u[0].bits.man != 0;
52 	nan_y = u[1].bits.exp == 255 && u[1].bits.man != 0;
53 
54 	if (nan_x || nan_y) {
55 		/* These ternary conditionals force (x+y), so that sNaN's raise exceptions */
56 		if (nan_x && nan_y)
57 			return (x + y);
58 		if (nan_x)
59 			return ((x + y) != 0.0 ? y : y);
60 		return ((x + y) != 0.0 ? x : x);
61 	}
62 
63 	/* Handle comparisons of signed zeroes. */
64 	if (u[0].bits.sign != u[1].bits.sign)
65 		return (u[u[1].bits.sign].f);
66 
67 	return (x < y ? x : y);
68 }
69 #endif
70 
71 
72