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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  */
      4 
      5 /*
      6  * ====================================================
      7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
      8  *
      9  * Developed at SunPro, a Sun Microsystems, Inc. business.
     10  * Permission to use, copy, modify, and distribute this
     11  * software is freely granted, provided that this notice
     12  * is preserved.
     13  * ====================================================
     14  */
     15 
     16 #include <sys/cdefs.h>
     17 #if defined(LIBM_SCCS) && !defined(lint)
     18 __RCSID("$NetBSD: k_sinf.c,v 1.7 2002/05/26 22:01:53 wiz Exp $");
     19 #endif
     20 
     21 #include "math.h"
     22 #include "math_private.h"
     23 
     24 static const float
     25 half =  5.0000000000e-01,/* 0x3f000000 */
     26 S1  = -1.6666667163e-01, /* 0xbe2aaaab */
     27 S2  =  8.3333337680e-03, /* 0x3c088889 */
     28 S3  = -1.9841270114e-04, /* 0xb9500d01 */
     29 S4  =  2.7557314297e-06, /* 0x3638ef1b */
     30 S5  = -2.5050759689e-08, /* 0xb2d72f34 */
     31 S6  =  1.5896910177e-10; /* 0x2f2ec9d3 */
     32 
     33 float
     34 __kernel_sinf(float x, float y, int iy)
     35 {
     36 	float z,r,v;
     37 	int32_t ix;
     38 	GET_FLOAT_WORD(ix,x);
     39 	ix &= 0x7fffffff;			/* high word of x */
     40 	if(ix<0x32000000)			/* |x| < 2**-27 */
     41 	   {if((int)x==0) return x;}		/* generate inexact */
     42 	z	=  x*x;
     43 	v	=  z*x;
     44 	r	=  S2+z*(S3+z*(S4+z*(S5+z*S6)));
     45 	if(iy==0) return x+v*(S1+z*r);
     46 	else      return x-((z*(half*y-v*r)-y)-v*S1);
     47 }
     48