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      1 /* kf_sin.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 "fdlibm.h"
     17 
     18 #ifdef __STDC__
     19 static const float
     20 #else
     21 static float
     22 #endif
     23 half =  5.0000000000e-01,/* 0x3f000000 */
     24 S1  = -1.6666667163e-01, /* 0xbe2aaaab */
     25 S2  =  8.3333337680e-03, /* 0x3c088889 */
     26 S3  = -1.9841270114e-04, /* 0xb9500d01 */
     27 S4  =  2.7557314297e-06, /* 0x3638ef1b */
     28 S5  = -2.5050759689e-08, /* 0xb2d72f34 */
     29 S6  =  1.5896910177e-10; /* 0x2f2ec9d3 */
     30 
     31 #ifdef __STDC__
     32 	float __kernel_sinf(float x, float y, int iy)
     33 #else
     34 	float __kernel_sinf(x, y, iy)
     35 	float x,y; int iy;		/* iy=0 if y is zero */
     36 #endif
     37 {
     38 	float z,r,v;
     39 	__int32_t ix;
     40 	GET_FLOAT_WORD(ix,x);
     41 	ix &= 0x7fffffff;			/* high word of x */
     42 	if(ix<0x32000000)			/* |x| < 2**-27 */
     43 	   {if((int)x==0) return x;}		/* generate inexact */
     44 	z	=  x*x;
     45 	v	=  z*x;
     46 	r	=  S2+z*(S3+z*(S4+z*(S5+z*S6)));
     47 	if(iy==0) return x+v*(S1+z*r);
     48 	else      return x-((z*(half*y-v*r)-y)-v*S1);
     49 }
     50