/*
* 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 == 1) {
y[0] = -y[0];
y[1] = -y[1];
return (-n);
}
return (n);
}