49 lines
1.3 KiB
C
49 lines
1.3 KiB
C
/* k_cosf.c -- float version of k_cos.c
|
|
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
|
|
* Debugged and 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 INLINE_KERNEL_COSDF
|
|
#include "cdefs-compat.h"
|
|
//__FBSDID("$FreeBSD: src/lib/msun/src/k_cosf.c,v 1.18 2009/06/03 08:16:34 ed Exp $");
|
|
#endif
|
|
|
|
#include <openlibm_math.h>
|
|
|
|
#include "math_private.h"
|
|
|
|
/* |cos(x) - c(x)| < 2**-34.1 (~[-5.37e-11, 5.295e-11]). */
|
|
static const double
|
|
one = 1.0,
|
|
C0 = -0x1ffffffd0c5e81.0p-54, /* -0.499999997251031003120 */
|
|
C1 = 0x155553e1053a42.0p-57, /* 0.0416666233237390631894 */
|
|
C2 = -0x16c087e80f1e27.0p-62, /* -0.00138867637746099294692 */
|
|
C3 = 0x199342e0ee5069.0p-68; /* 0.0000243904487962774090654 */
|
|
|
|
#ifndef INLINE_KERNEL_COSDF
|
|
extern
|
|
#endif
|
|
//__inline float
|
|
OLM_DLLEXPORT float
|
|
__kernel_cosdf(double x)
|
|
{
|
|
double r, w, z;
|
|
|
|
/* Try to optimize for parallel evaluation as in k_tanf.c. */
|
|
z = x*x;
|
|
w = z*z;
|
|
r = C2+z*C3;
|
|
return ((one+z*C0) + w*C1) + (w*z)*r;
|
|
}
|