/* 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 "libc/math/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; }