1 /* origin: FreeBSD /usr/src/lib/msun/src/k_sinf.c */
2 /*
3 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
4 * Optimized by Bruce D. Evans.
5 */
6 /*
7 * ====================================================
8 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
9 *
10 * Developed at SunPro, a Sun Microsystems, Inc. business.
11 * Permission to use, copy, modify, and distribute this
12 * software is freely granted, provided that this notice
13 * is preserved.
14 * ====================================================
15 */
16
17 #include "libm.h"
18
19 /* |sin(x)/x - s(x)| < 2**-37.5 (~[-4.89e-12, 4.824e-12]). */
20 static const double
21 S1 = -0x15555554cbac77.0p-55, /* -0.166666666416265235595 */
22 S2 = 0x111110896efbb2.0p-59, /* 0.0083333293858894631756 */
23 S3 = -0x1a00f9e2cae774.0p-65, /* -0.000198393348360966317347 */
24 S4 = 0x16cd878c3b46a7.0p-71; /* 0.0000027183114939898219064 */
25
__sindf(double x)26 float __sindf(double x)
27 {
28 double_t r, s, w, z;
29
30 /* Try to optimize for parallel evaluation as in __tandf.c. */
31 z = x*x;
32 w = z*z;
33 r = S3 + z*S4;
34 s = z*x;
35 return (x + s*(S1 + z*S2)) + s*w*r;
36 }
37