/home/jaouen/pok_official/pok/trunk/libpok/libm/k_sinf.c

/*
 *                               POK header
 * 
 * The following file is a part of the POK project. Any modification should
 * made according to the POK licence. You CANNOT use this file or a part of
 * this file is this part of a file for your own project
 *
 * For more information on the POK licence, please see our LICENCE FILE
 *
 * Please follow the coding guidelines described in doc/CODING_GUIDELINES
 *
 *                                      Copyright (c) 2007-2009 POK team 
 *
 * Created by julien on Sat Jan 31 20:12:07 2009 
 */

/* k_sinf.c -- float version of k_sin.c
 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
 */

/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunPro, a Sun Microsystems, Inc. business.
 * Permission to use, copy, modify, and distribute this
 * software is freely granted, provided that this notice
 * is preserved.
 * ====================================================
 */

#ifdef POK_NEEDS_LIBMATH

#include <libm.h>
#include "math_private.h"

static const float
half =  5.0000000000e-01,/* 0x3f000000 */
S1  = -1.6666667163e-01, /* 0xbe2aaaab */
S2  =  8.3333337680e-03, /* 0x3c088889 */
S3  = -1.9841270114e-04, /* 0xb9500d01 */
S4  =  2.7557314297e-06, /* 0x3638ef1b */
S5  = -2.5050759689e-08, /* 0xb2d72f34 */
S6  =  1.5896910177e-10; /* 0x2f2ec9d3 */

float
__kernel_sinf(float x, float y, int iy)
{
        float z,r,v;
        int32_t ix;
        GET_FLOAT_WORD(ix,x);
        ix &= 0x7fffffff;                       /* high word of x */
        if(ix<0x32000000)                       /* |x| < 2**-27 */
           {if((int)x==0) return x;}            /* generate inexact */
        z       =  x*x;
        v       =  z*x;
        r       =  S2+z*(S3+z*(S4+z*(S5+z*S6)));
        if(iy==0) return x+v*(S1+z*r);
        else      return x-((z*(half*y-v*r)-y)-v*S1);
}

#endif