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      1 /* k_sinf.c -- float version of k_sin.c
      2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian (at) 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 #endif
     20 
     21 #include "math.h"
     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 }
     46