1*cfe182f3Schristos /* From: @(#)k_sin.c 1.3 95/01/18 */
2*cfe182f3Schristos /*
3*cfe182f3Schristos * ====================================================
4*cfe182f3Schristos * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
5*cfe182f3Schristos * Copyright (c) 2008 Steven G. Kargl, David Schultz, Bruce D. Evans.
6*cfe182f3Schristos *
7*cfe182f3Schristos * Developed at SunSoft, a Sun Microsystems, Inc. business.
8*cfe182f3Schristos * Permission to use, copy, modify, and distribute this
9*cfe182f3Schristos * software is freely granted, provided that this notice
10*cfe182f3Schristos * is preserved.
11*cfe182f3Schristos * ====================================================
12*cfe182f3Schristos */
13*cfe182f3Schristos
14*cfe182f3Schristos #include <sys/cdefs.h>
15*cfe182f3Schristos /*
16*cfe182f3Schristos * ld80 version of k_sin.c. See ../src/k_sin.c for most comments.
17*cfe182f3Schristos */
18*cfe182f3Schristos
19*cfe182f3Schristos #include "math_private.h"
20*cfe182f3Schristos
21*cfe182f3Schristos static const double
22*cfe182f3Schristos half = 0.5;
23*cfe182f3Schristos
24*cfe182f3Schristos /*
25*cfe182f3Schristos * Domain [-0.7854, 0.7854], range ~[-1.89e-22, 1.915e-22]
26*cfe182f3Schristos * |sin(x)/x - s(x)| < 2**-72.1
27*cfe182f3Schristos *
28*cfe182f3Schristos * See ../ld80/k_cosl.c for more details about the polynomial.
29*cfe182f3Schristos */
30*cfe182f3Schristos #if defined(__amd64__) || defined(__i386__)
31*cfe182f3Schristos /* Long double constants are slow on these arches, and broken on i386. */
32*cfe182f3Schristos static const volatile double
33*cfe182f3Schristos S1hi = -0.16666666666666666, /* -0x15555555555555.0p-55 */
34*cfe182f3Schristos S1lo = -9.2563760475949941e-18; /* -0x15580000000000.0p-109 */
35*cfe182f3Schristos #define S1 ((long double)S1hi + S1lo)
36*cfe182f3Schristos #else
37*cfe182f3Schristos static const long double
38*cfe182f3Schristos S1 = -0.166666666666666666671L; /* -0xaaaaaaaaaaaaaaab.0p-66 */
39*cfe182f3Schristos #endif
40*cfe182f3Schristos
41*cfe182f3Schristos static const double
42*cfe182f3Schristos S2 = 0.0083333333333333332, /* 0x11111111111111.0p-59 */
43*cfe182f3Schristos S3 = -0.00019841269841269427, /* -0x1a01a01a019f81.0p-65 */
44*cfe182f3Schristos S4 = 0.0000027557319223597490, /* 0x171de3a55560f7.0p-71 */
45*cfe182f3Schristos S5 = -0.000000025052108218074604, /* -0x1ae64564f16cad.0p-78 */
46*cfe182f3Schristos S6 = 1.6059006598854211e-10, /* 0x161242b90243b5.0p-85 */
47*cfe182f3Schristos S7 = -7.6429779983024564e-13, /* -0x1ae42ebd1b2e00.0p-93 */
48*cfe182f3Schristos S8 = 2.6174587166648325e-15; /* 0x179372ea0b3f64.0p-101 */
49*cfe182f3Schristos
50*cfe182f3Schristos long double
__kernel_sinl(long double x,long double y,int iy)51*cfe182f3Schristos __kernel_sinl(long double x, long double y, int iy)
52*cfe182f3Schristos {
53*cfe182f3Schristos long double z,r,v;
54*cfe182f3Schristos
55*cfe182f3Schristos z = x*x;
56*cfe182f3Schristos v = z*x;
57*cfe182f3Schristos r = S2+z*(S3+z*(S4+z*(S5+z*(S6+z*(S7+z*S8)))));
58*cfe182f3Schristos if(iy==0) return x+v*(S1+z*r);
59*cfe182f3Schristos else return x-((z*(half*y-v*r)-y)-v*S1);
60*cfe182f3Schristos }
61