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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 #ifndef lint
     19 static char rcsid[] = "$FreeBSD: src/lib/msun/src/k_sinf.c,v 1.13 2005/11/30 11:51:17 bde Exp $";
     20 #endif
     21 #endif
     22 
     23 #include "math.h"
     24 #include "math_private.h"
     25 
     26 /* |sin(x)/x - s(x)| < 2**-37.5 (~[-4.89e-12, 4.824e-12]). */
     27 static const double
     28 S1 = -0x15555554cbac77.0p-55,	/* -0.166666666416265235595 */
     29 S2 =  0x111110896efbb2.0p-59,	/*  0.0083333293858894631756 */
     30 S3 = -0x1a00f9e2cae774.0p-65,	/* -0.000198393348360966317347 */
     31 S4 =  0x16cd878c3b46a7.0p-71;	/*  0.0000027183114939898219064 */
     32 
     33 #ifdef INLINE_KERNEL_SINDF
     34 extern inline
     35 #endif
     36 float
     37 __kernel_sindf(double x)
     38 {
     39 	double r, s, w, z;
     40 
     41 	/* Try to optimize for parallel evaluation as in k_tanf.c. */
     42 	z = x*x;
     43 	w = z*z;
     44 	r = S3+z*S4;
     45 	s = z*x;
     46 	return (x + s*(S1+z*S2)) + s*w*r;
     47 }
     48