| /* origin: FreeBSD /usr/src/lib/msun/src/k_sinf.c */ |
| /* |
| * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. |
| * Optimized by Bruce D. Evans. |
| */ |
| /* |
| * ==================================================== |
| * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
| * |
| * Developed at SunPro, a Sun Microsystems, Inc. business. |
| * Permission to use, copy, modify, and distribute this |
| * software is freely granted, provided that this notice |
| * is preserved. |
| * ==================================================== |
| */ |
| |
| #include "libm.h" |
| |
| /* |sin(x)/x - s(x)| < 2**-37.5 (~[-4.89e-12, 4.824e-12]). */ |
| static const double |
| S1 = -0x15555554cbac77.0p-55, /* -0.166666666416265235595 */ |
| S2 = 0x111110896efbb2.0p-59, /* 0.0083333293858894631756 */ |
| S3 = -0x1a00f9e2cae774.0p-65, /* -0.000198393348360966317347 */ |
| S4 = 0x16cd878c3b46a7.0p-71; /* 0.0000027183114939898219064 */ |
| |
| float __sindf(double x) |
| { |
| double_t r, s, w, z; |
| |
| /* Try to optimize for parallel evaluation as in __tandf.c. */ |
| z = x*x; |
| w = z*z; |
| r = S3 + z*S4; |
| s = z*x; |
| return (x + s*(S1 + z*S2)) + s*w*r; |
| } |
