1 /* $NetBSD: n_sincos.c,v 1.11 2024/07/16 14:53:17 riastradh Exp $ */
2 /*
3 * Copyright (c) 1987, 1993
4 * The Regents of the University of California. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <sys/cdefs.h>
32 __RCSID("$NetBSD: n_sincos.c,v 1.11 2024/07/16 14:53:17 riastradh Exp $");
33
34 #ifndef lint
35 #if 0
36 static char sccsid[] = "@(#)sincos.c 8.1 (Berkeley) 6/4/93";
37 #endif
38 #endif /* not lint */
39
40 #define _LIBM_DECLARE
41 #include "namespace.h"
42 #include "mathimpl.h"
43 #include "trig.h"
44
__weak_alias(sinl,_sinl)45 __weak_alias(sinl, _sinl)
46 __strong_alias(_sinl, _sin)
47
48 __weak_alias(cosl, _cosl)
49 __strong_alias(_cosl, _cos)
50
51 __weak_alias(sin, _sin)
52 double
53 sin(double x)
54 {
55 double a,c,z;
56
57 if(!finite(x)) /* sin(NaN) and sin(INF) must be NaN */
58 return x-x;
59 x=drem(x,PI2); /* reduce x into [-PI,PI] */
60 a=copysign(x,__one);
61 if (a >= PIo4) {
62 if(a >= PI3o4) /* ... in [3PI/4,PI] */
63 x = copysign((a = PI-a),x);
64 else { /* ... in [PI/4,3PI/4] */
65 a = PIo2-a; /* rtn. sign(x)*C(PI/2-|x|) */
66 z = a*a;
67 c = cos__C(z);
68 z *= __half;
69 a = (z >= thresh ? __half-((z-__half)-c) : __one-(z-c));
70 return copysign(a,x);
71 }
72 }
73
74 if (a < __small) { /* rtn. S(x) */
75 z = __big+a;
76 return x;
77 }
78 return x+x*sin__S(x*x);
79 }
80
__weak_alias(sinf,_sinf)81 __weak_alias(sinf, _sinf)
82 float
83 sinf(float x)
84 {
85 return sin(x);
86 }
87
__weak_alias(cos,_cos)88 __weak_alias(cos, _cos)
89 double
90 cos(double x)
91 {
92 double a,c,z,s = 1.0;
93
94 if(!finite(x)) /* cos(NaN) and cos(INF) must be NaN */
95 return x-x;
96 x=drem(x,PI2); /* reduce x into [-PI,PI] */
97 a=copysign(x,__one);
98 if (a >= PIo4) {
99 if (a >= PI3o4) { /* ... in [3PI/4,PI] */
100 a = PI-a;
101 s = __negone;
102 }
103 else { /* ... in [PI/4,3PI/4] */
104 a = PIo2-a;
105 return a+a*sin__S(a*a); /* rtn. S(PI/2-|x|) */
106 }
107 }
108 if (a < __small) {
109 z = __big+a;
110 return s; /* rtn. s*C(a) */
111 }
112 z = a*a;
113 c = cos__C(z);
114 z *= __half;
115 a = (z >= thresh ? __half-((z-__half)-c) : __one-(z-c));
116 return copysign(a,s);
117 }
118
__weak_alias(cosf,_cosf)119 __weak_alias(cosf, _cosf)
120 float
121 cosf(float x)
122 {
123 return cos(x);
124 }
125