k_sinf.c

Go to the documentation of this file.

/* 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.
 * ====================================================
 */

#include "math.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);
}