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