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
15 /*
16 * ld80 version of k_sin.c. See ../src/k_sin.c for most comments.
17 */
18
19
20 /*
21 * Domain [-0.7854, 0.7854], range ~[-1.89e-22, 1.915e-22]
22 * |sin(x)/x - s(x)| < 2**-72.1
23 *
24 * See ../ld80/k_cosl.c for more details about the polynomial.
25 */
26 #if defined(__amd64__) || defined(__i386__)
27 /* Long double constants are slow on these arches, and broken on i386. */
28 static const volatile double
29 S1hi = -0.16666666666666666, /* -0x15555555555555.0p-55 */
30 S1lo = -9.2563760475949941e-18; /* -0x15580000000000.0p-109 */
31 #define S1 ((long double)S1hi + (long double)S1lo)
32 #else
33 static const long double
34 S1 = -0.166666666666666666671L; /* -0xaaaaaaaaaaaaaaab.0p-66 */
35 #endif
36
37 static const double
38 S2 = 0.0083333333333333332, /* 0x11111111111111.0p-59 */
39 S3 = -0.00019841269841269427, /* -0x1a01a01a019f81.0p-65 */
40 S4 = 0.0000027557319223597490, /* 0x171de3a55560f7.0p-71 */
41 S5 = -0.000000025052108218074604, /* -0x1ae64564f16cad.0p-78 */
42 S6 = 1.6059006598854211e-10, /* 0x161242b90243b5.0p-85 */
43 S7 = -7.6429779983024564e-13, /* -0x1ae42ebd1b2e00.0p-93 */
44 S8 = 2.6174587166648325e-15; /* 0x179372ea0b3f64.0p-101 */
45
46 long double
__kernel_sinl(long double x,long double y,int iy)47 __kernel_sinl(long double x, long double y, int iy)
48 {
49 long double z,r,v;
50
51 z = x*x;
52 v = z*x;
53 r = (long double) S2+z*((long double) S3+z*((long double) S4+z*((long double) S5+z*((long double) S6+z*((long double) S7+z*(long double) S8)))));
54 if(iy==0) return x+v*(S1+z*r);
55 else return x-((z*(0.5l*y-v*r)-y)-v*S1);
56 }
57
