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/*-
 * ====================================================
 * 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.
 * ====================================================
 *
 * k_sinf.c and k_cosf.c merged by Steven G. Kargl.
 */

#include <sys/cdefs.h>
#if 0
__FBSDID("$FreeBSD: head/lib/msun/src/k_sincosf.h 319047 2017-05-28 06:13:38Z mmel $");
#endif
#if defined(LIBM_SCCS) && !defined(lint)
__RCSID("$NetBSD: k_sincosf.h,v 1.1 2022/08/27 08:31:59 christos Exp $");
#endif

/* |sin(x)/x - s(x)| < 2**-37.5 (~[-4.89e-12, 4.824e-12]). */
static const double
S1 = -0x15555554cbac77.0p-55,	/* -0.166666666416265235595 */
S2 =  0x111110896efbb2.0p-59,	/*  0.0083333293858894631756 */
S3 = -0x1a00f9e2cae774.0p-65,	/* -0.000198393348360966317347 */
S4 =  0x16cd878c3b46a7.0p-71;	/*  0.0000027183114939898219064 */

/* |cos(x) - c(x)| < 2**-34.1 (~[-5.37e-11, 5.295e-11]). */
static const double
C0  = -0x1ffffffd0c5e81.0p-54,	/* -0.499999997251031003120 */
C1  =  0x155553e1053a42.0p-57,	/*  0.0416666233237390631894 */
C2  = -0x16c087e80f1e27.0p-62,	/* -0.00138867637746099294692 */
C3  =  0x199342e0ee5069.0p-68;	/*  0.0000243904487962774090654 */

static inline void
__kernel_sincosdf(double x, float *sn, float *cs)
{
	double r, s, w, z;

	z = x * x;
	w = z * z;
	r = S3 + z * S4;
	s = z * x;
	*sn = (x + s * (S1 + z * S2)) + s * w * r;
	r = C2 + z * C3;
	*cs = ((1 + z * C0) + w * C1) + (w * z) * r;
}