xref: /freebsd/lib/msun/ld128/k_sinl.c (revision 61ba55bcf70f2340f9c943c9571113b3fd8eda69)
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 /*
16  * ld128 version of k_sin.c.  See ../src/k_sin.c for most comments.
17  */
18 
19 #include "math_private.h"
20 
21 static const double
22 half =  0.5;
23 
24 /*
25  * Domain [-0.7854, 0.7854], range ~[-1.53e-37, 1.659e-37]
26  * |sin(x)/x - s(x)| < 2**-122.1
27  *
28  * See ../ld80/k_cosl.c for more details about the polynomial.
29  */
30 static const long double
31 S1 = -0.16666666666666666666666666666666666606732416116558L,
32 S2 =  0.0083333333333333333333333333333331135404851288270047L,
33 S3 = -0.00019841269841269841269841269839935785325638310428717L,
34 S4 =  0.27557319223985890652557316053039946268333231205686e-5L,
35 S5 = -0.25052108385441718775048214826384312253862930064745e-7L,
36 S6 =  0.16059043836821614596571832194524392581082444805729e-9L,
37 S7 = -0.76471637318198151807063387954939213287488216303768e-12L,
38 S8 =  0.28114572543451292625024967174638477283187397621303e-14L;
39 
40 static const double
41 S9  = -0.82206352458348947812512122163446202498005154296863e-17,
42 S10 =  0.19572940011906109418080609928334380560135358385256e-19,
43 S11 = -0.38680813379701966970673724299207480965452616911420e-22,
44 S12 =  0.64038150078671872796678569586315881020659912139412e-25;
45 
46 long double
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	=  S2+z*(S3+z*(S4+z*(S5+z*(S6+z*(S7+z*(S8+
54 	    z*(S9+z*(S10+z*(S11+z*S12)))))))));
55 	if(iy==0) return x+v*(S1+z*r);
56 	else      return x-((z*(half*y-v*r)-y)-v*S1);
57 }
58