1 /* From: @(#)k_sin.c 1.3 95/01/18 */ 2 /* 3 * ==================================================== 4 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 5 * Copyright (c) 2008 Steven G. Kargl, David Schultz, Bruce D. Evans. 6 * 7 * Developed at SunSoft, a Sun Microsystems, Inc. business. 8 * Permission to use, copy, modify, and distribute this 9 * software is freely granted, provided that this notice 10 * is preserved. 11 * ==================================================== 12 */ 13 14 #include <sys/cdefs.h> 15 __FBSDID("$FreeBSD$"); 16 17 /* 18 * ld80 version of k_sin.c. See ../src/k_sin.c for most comments. 19 */ 20 21 #include "math_private.h" 22 23 static const double 24 half = 0.5; 25 26 /* 27 * Domain [-0.7854, 0.7854], range ~[-1.89e-22, 1.915e-22] 28 * |sin(x)/x - s(x)| < 2**-72.1 29 * 30 * See ../ld80/k_cosl.c for more details about the polynomial. 31 */ 32 #if defined(__amd64__) || defined(__i386__) 33 /* Long double constants are slow on these arches, and broken on i386. */ 34 static const volatile double 35 S1hi = -0.16666666666666666, /* -0x15555555555555.0p-55 */ 36 S1lo = -9.2563760475949941e-18; /* -0x15580000000000.0p-109 */ 37 #define S1 ((long double)S1hi + S1lo) 38 #else 39 static const long double 40 S1 = -0.166666666666666666671L; /* -0xaaaaaaaaaaaaaaab.0p-66 */ 41 #endif 42 43 static const double 44 S2 = 0.0083333333333333332, /* 0x11111111111111.0p-59 */ 45 S3 = -0.00019841269841269427, /* -0x1a01a01a019f81.0p-65 */ 46 S4 = 0.0000027557319223597490, /* 0x171de3a55560f7.0p-71 */ 47 S5 = -0.000000025052108218074604, /* -0x1ae64564f16cad.0p-78 */ 48 S6 = 1.6059006598854211e-10, /* 0x161242b90243b5.0p-85 */ 49 S7 = -7.6429779983024564e-13, /* -0x1ae42ebd1b2e00.0p-93 */ 50 S8 = 2.6174587166648325e-15; /* 0x179372ea0b3f64.0p-101 */ 51 52 long double 53 __kernel_sinl(long double x, long double y, int iy) 54 { 55 long double z,r,v; 56 57 z = x*x; 58 v = z*x; 59 r = S2+z*(S3+z*(S4+z*(S5+z*(S6+z*(S7+z*S8))))); 60 if(iy==0) return x+v*(S1+z*r); 61 else return x-((z*(half*y-v*r)-y)-v*S1); 62 } 63