/*-
 * ====================================================
 * 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.
 * ====================================================
 *
 * s_sin.c and s_cos.c merged by Steven G. Kargl.  Descriptions of the
 * algorithms are contained in the original files.
 */

#include <sys/cdefs.h>
#if defined(LIBM_SCCS) && !defined(lint)
__RCSID("$NetBSD: s_sincos.c,v 1.5 2022/08/29 01:48:34 riastradh Exp $");
#endif
#if 0
__FBSDID("$FreeBSD: head/lib/msun/src/s_sincos.c 319047 2017-05-28 06:13:38Z mmel $");
#endif

#include "namespace.h"
#include <float.h>

#include "math.h"
// #define INLINE_REM_PIO2
#include "math_private.h"
// #include "e_rem_pio2.c"
#include "k_sincos.h"

#ifdef __weak_alias
__weak_alias(sincos,_sincos)
#endif

void
sincos(double x, double *sn, double *cs)
{
        double y[2];
        int32_t n, ix;

        /* High word of x. */
        GET_HIGH_WORD(ix, x);

        /* |x| ~< pi/4 */
        ix &= 0x7fffffff;
        if (ix <= 0x3fe921fb) {
                if (ix < 0x3e400000) {          /* |x| < 2**-27 */
                        if ((int)x == 0) {      /* Generate inexact. */
                                *sn = x;
                                *cs = 1;
                                return;
                        }
                }
                __kernel_sincos(x, 0, 0, sn, cs);
                return;
        }

        /* If x = Inf or NaN, then sin(x) = NaN and cos(x) = NaN. */
        if (ix >= 0x7ff00000) {
                *sn = x - x;
                *cs = x - x;
                return;
        }

        /* Argument reduction. */
        n = __ieee754_rem_pio2(x, y);

        switch(n & 3) {
        case 0:
                __kernel_sincos(y[0], y[1], 1, sn, cs);
                break;
        case 1:
                __kernel_sincos(y[0], y[1], 1, cs, sn);
                *cs = -*cs;
                break;
        case 2:
                __kernel_sincos(y[0], y[1], 1, sn, cs);
                *sn = -*sn;
                *cs = -*cs;
                break;
        default:
                __kernel_sincos(y[0], y[1], 1, cs, sn);
                *sn = -*sn;
        }
}

#if !defined(__HAVE_LONG_DOUBLE)
__weak_alias(sincosl, sincos);
#endif