xref: /freebsd/lib/msun/ld128/k_sinl.c (revision 81ad6265)
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  * ld128 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 ~[-1.53e-37, 1.659e-37]
28  * |sin(x)/x - s(x)| < 2**-122.1
29  *
30  * See ../ld80/k_cosl.c for more details about the polynomial.
31  */
32 static const long double
33 S1 = -0.16666666666666666666666666666666666606732416116558L,
34 S2 =  0.0083333333333333333333333333333331135404851288270047L,
35 S3 = -0.00019841269841269841269841269839935785325638310428717L,
36 S4 =  0.27557319223985890652557316053039946268333231205686e-5L,
37 S5 = -0.25052108385441718775048214826384312253862930064745e-7L,
38 S6 =  0.16059043836821614596571832194524392581082444805729e-9L,
39 S7 = -0.76471637318198151807063387954939213287488216303768e-12L,
40 S8 =  0.28114572543451292625024967174638477283187397621303e-14L;
41 
42 static const double
43 S9  = -0.82206352458348947812512122163446202498005154296863e-17,
44 S10 =  0.19572940011906109418080609928334380560135358385256e-19,
45 S11 = -0.38680813379701966970673724299207480965452616911420e-22,
46 S12 =  0.64038150078671872796678569586315881020659912139412e-25;
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 	    z*(S9+z*(S10+z*(S11+z*S12)))))))));
57 	if(iy==0) return x+v*(S1+z*r);
58 	else      return x-((z*(half*y-v*r)-y)-v*S1);
59 }
60