k_sinf.cpp (1230B)
1 /* k_sinf.c -- float version of k_sin.c 2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 3 * Optimized by Bruce D. Evans. 4 */ 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 #ifndef INLINE_KERNEL_SINDF 18 //#include <sys/cdefs.h> 19 //__FBSDID("$FreeBSD$"); 20 #endif 21 22 #include "math_private.h" 23 24 /* |sin(x)/x - s(x)| < 2**-37.5 (~[-4.89e-12, 4.824e-12]). */ 25 static const double 26 S1 = -0x15555554cbac77.0p-55, /* -0.166666666416265235595 */ 27 S2 = 0x111110896efbb2.0p-59, /* 0.0083333293858894631756 */ 28 S3 = -0x1a00f9e2cae774.0p-65, /* -0.000198393348360966317347 */ 29 S4 = 0x16cd878c3b46a7.0p-71; /* 0.0000027183114939898219064 */ 30 31 #ifdef INLINE_KERNEL_SINDF 32 static __inline 33 #endif 34 float 35 __kernel_sindf(double x) 36 { 37 double r, s, w, z; 38 39 /* Try to optimize for parallel evaluation as in k_tanf.c. */ 40 z = x*x; 41 w = z*z; 42 r = S3+z*S4; 43 s = z*x; 44 return (x + s*(S1+z*S2)) + s*w*r; 45 }