1 /*- 2 * Copyright (c) 2017,2023 Steven G. Kargl 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * 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 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 /* 29 * See ../src/s_cospi.c for implementation details. 30 */ 31 #define INLINE_KERNEL_SINDF 32 #define INLINE_KERNEL_COSDF 33 34 #include "namespace.h" 35 __weak_alias(cospif, _cospif) 36 37 #include "math.h" 38 #include "math_private.h" 39 #include "k_cosdf.c" 40 #include "k_sindf.c" 41 42 #define __kernel_cospif(x) (__kernel_cosdf(M_PI * (x))) 43 #define __kernel_sinpif(x) (__kernel_sindf(M_PI * (x))) 44 45 static volatile const float vzero = 0; 46 47 float 48 cospif(float x) 49 { 50 float ax, c; 51 uint32_t ix, jj0; 52 53 GET_FLOAT_WORD(ix, x); 54 ix = ix & 0x7fffffff; 55 SET_FLOAT_WORD(ax, ix); 56 57 if (ix < 0x3f800000) { /* |x| < 1 */ 58 if (ix < 0x3e800000) { /* |x| < 0.25 */ 59 if (ix < 0x38800000) { /* |x| < 0x1p-14 */ 60 /* Raise inexact iff != 0. */ 61 if ((int)ax == 0) 62 return (1); 63 } 64 return (__kernel_cospif(ax)); 65 } 66 67 if (ix < 0x3f000000) /* |x| < 0.5 */ 68 c = __kernel_sinpif(0.5F - ax); 69 else if (ix < 0x3f400000) { /* |x| < 0.75 */ 70 if (ix == 0x3f000000) 71 return (0); 72 c = -__kernel_sinpif(ax - 0.5F); 73 } else 74 c = -__kernel_cospif(1 - ax); 75 return (c); 76 } 77 78 if (ix < 0x4b000000) { /* 1 <= |x| < 0x1p23 */ 79 FFLOORF(x, jj0, ix); /* Integer part of ax. */ 80 ax -= x; 81 GET_FLOAT_WORD(ix, ax); 82 83 if (ix < 0x3f000000) { /* |x| < 0.5 */ 84 if (ix < 0x3e800000) /* |x| < 0.25 */ 85 c = ix == 0 ? 1 : __kernel_cospif(ax); 86 else 87 c = __kernel_sinpif(0.5F - ax); 88 } else { 89 if (ix < 0x3f400000) { /* |x| < 0.75 */ 90 if (ix == 0x3f000000) 91 return (0); 92 c = -__kernel_sinpif(ax - 0.5F); 93 } else 94 c = -__kernel_cospif(1 - ax); 95 } 96 97 jj0 = (uint32_t)x; 98 return (jj0 & 1 ? -c : c); 99 } 100 101 /* x = +-inf or nan. */ 102 if (ix >= 0x7f800000) 103 return (vzero / vzero); 104 105 /* 106 * For 0x1p23 <= |x| < 0x1p24 need to determine if x is an even 107 * or odd integer to return +1 or -1. 108 * For |x| >= 0x1p24, it is always an even integer, so return 1. 109 */ 110 return (ix < 0x4b800000 ? ((ix & 1) ? -1 : 1) : 1); 111 } 112