1 /* $NetBSD: n_sincos.c,v 1.10 2024/05/08 01:40:27 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 #ifndef lint 32 #if 0 33 static char sccsid[] = "@(#)sincos.c 8.1 (Berkeley) 6/4/93"; 34 #endif 35 #endif /* not lint */ 36 37 #define _LIBM_DECLARE 38 #include "namespace.h" 39 #include "mathimpl.h" 40 #include "trig.h" 41 42 __weak_alias(sinl, _sinl) 43 __strong_alias(_sinl, _sin) 44 45 __weak_alias(cosl, _cosl) 46 __strong_alias(_cosl, _cos) 47 48 __weak_alias(sin, _sin) 49 double 50 sin(double x) 51 { 52 double a,c,z; 53 54 if(!finite(x)) /* sin(NaN) and sin(INF) must be NaN */ 55 return x-x; 56 x=drem(x,PI2); /* reduce x into [-PI,PI] */ 57 a=copysign(x,__one); 58 if (a >= PIo4) { 59 if(a >= PI3o4) /* ... in [3PI/4,PI] */ 60 x = copysign((a = PI-a),x); 61 else { /* ... in [PI/4,3PI/4] */ 62 a = PIo2-a; /* rtn. sign(x)*C(PI/2-|x|) */ 63 z = a*a; 64 c = cos__C(z); 65 z *= __half; 66 a = (z >= thresh ? __half-((z-__half)-c) : __one-(z-c)); 67 return copysign(a,x); 68 } 69 } 70 71 if (a < __small) { /* rtn. S(x) */ 72 z = __big+a; 73 return x; 74 } 75 return x+x*sin__S(x*x); 76 } 77 78 __weak_alias(sinf, _sinf) 79 float 80 sinf(float x) 81 { 82 return sin(x); 83 } 84 85 __weak_alias(cos, _cos) 86 double 87 cos(double x) 88 { 89 double a,c,z,s = 1.0; 90 91 if(!finite(x)) /* cos(NaN) and cos(INF) must be NaN */ 92 return x-x; 93 x=drem(x,PI2); /* reduce x into [-PI,PI] */ 94 a=copysign(x,__one); 95 if (a >= PIo4) { 96 if (a >= PI3o4) { /* ... in [3PI/4,PI] */ 97 a = PI-a; 98 s = __negone; 99 } 100 else { /* ... in [PI/4,3PI/4] */ 101 a = PIo2-a; 102 return a+a*sin__S(a*a); /* rtn. S(PI/2-|x|) */ 103 } 104 } 105 if (a < __small) { 106 z = __big+a; 107 return s; /* rtn. s*C(a) */ 108 } 109 z = a*a; 110 c = cos__C(z); 111 z *= __half; 112 a = (z >= thresh ? __half-((z-__half)-c) : __one-(z-c)); 113 return copysign(a,s); 114 } 115 116 __weak_alias(cosf, _cosf) 117 float 118 cosf(float x) 119 { 120 return cos(x); 121 } 122 123 void 124 sincos(double x, double *s, double *c) 125 { 126 *s = sin(x); 127 *c = cos(x); 128 } 129 130 void 131 sincosf(float x, float *s, float *c) 132 { 133 *s = sinf(x); 134 *c = cosf(x); 135 } 136