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/* k_sinf.c -- float version of k_sin.c
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
* Optimized by Bruce D. Evans.
*/
/*
* ====================================================
* 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.
* ====================================================
*/
#ifndef lint
static char rcsid[] = "$FreeBSD$";
#endif
#include "math.h"
#include "math_private.h"
/* |sin(x)/x - s(x)| < 2**-32.5 (~[-1.57e-10, 1.572e-10]). */
static const float
half = 0.5,
S1 = -0xaaaaab.0p-26, /* -0.16666667163 */
S2 = 0x8888bb.0p-30, /* 0.0083333803341 */
S3 = -0xd02de1.0p-36, /* -0.00019853517006 */
S4 = 0xbe6dbe.0p-42; /* 0.0000028376084629 */
float
__kernel_sinf(float x, float y, int iy)
{
float z,r,v;
z = x*x;
v = z*x;
r = S2+z*(S3+z*S4);
if(iy==0) return x+v*(S1+z*r);
else return x-((z*(half*y-v*r)-y)-v*S1);
}
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