/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
 */
/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * __rem_pio2l(x,y)
 *
 * return the remainder of x rem pi/2 in y[0]+y[1]
 * by calling __rem_pio2m
 */

#include "libm.h"
#include "longdouble.h"

extern const int _TBL_ipio2l_inf[];

static const long double
    two24l = 16777216.0L,
    pio4   = 0.7853981633974483096156608458198757210495L;

int
__rem_pio2l(long double x, long double *y)
{
        long double     z, w;
        double          t[3], v[5];
        int             e0, i, nx, n, sign;

        sign = signbitl(x);
        z = fabsl(x);
        if (z <= pio4) {
                y[0] = x;
                y[1] = 0;
                return (0);
        }
        e0 = ilogbl(z) - 23;
        z = scalbnl(z, -e0);
        for (i = 0; i < 3; i++) {
                t[i] = (double)((int)(z));
                z = (z - (long double)t[i]) * two24l;
        }
        nx = 3;
        while (t[nx-1] == 0.0)
                nx--;   /* omit trailing zeros */
        n = __rem_pio2m(t, v, e0, nx, 2, _TBL_ipio2l_inf);
        z = (long double)v[1];
        w = (long double)v[0];
        y[0] = z + w;
        y[1] = z - (y[0] - w);
        if (sign != 0) {
                y[0] = -y[0];
                y[1] = -y[1];
                return (-n);
        }
        return (n);
}