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
23static const double
24half =  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. */
34static const volatile double
35S1hi = -0.16666666666666666,		/* -0x15555555555555.0p-55 */
36S1lo = -9.2563760475949941e-18;		/* -0x15580000000000.0p-109 */
37#define	S1	((long double)S1hi + S1lo)
38#else
39static const long double
40S1 = -0.166666666666666666671L;		/* -0xaaaaaaaaaaaaaaab.0p-66 */
41#endif
42
43static const double
44S2 =  0.0083333333333333332,		/*  0x11111111111111.0p-59 */
45S3 = -0.00019841269841269427,		/* -0x1a01a01a019f81.0p-65 */
46S4 =  0.0000027557319223597490,		/*  0x171de3a55560f7.0p-71 */
47S5 = -0.000000025052108218074604,	/* -0x1ae64564f16cad.0p-78 */
48S6 =  1.6059006598854211e-10,		/*  0x161242b90243b5.0p-85 */
49S7 = -7.6429779983024564e-13,		/* -0x1ae42ebd1b2e00.0p-93 */
50S8 =  2.6174587166648325e-15;		/*  0x179372ea0b3f64.0p-101 */
51
52long 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