/*
* 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 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma weak __floor = floor
/*
* floor(x) returns the biggest integral value less than or equal to x.
* NOTE: floor(x) returns result with the same sign as x's, including 0.
*
* Modified 8/4/04 for performance.
*/
#include "libm.h"
static const double
zero = 0.0,
one = 1.0,
two52 = 4503599627370496.0;
double
floor(double x) {
double t, w;
int hx, lx, ix;
hx = ((int *)&x)[HIWORD];
lx = ((int *)&x)[LOWORD];
ix = hx & ~0x80000000;
if (ix >= 0x43300000) /* return x if |x| >= 2^52, or x is NaN */
return (x * one);
t = (hx >= 0)? two52 : -two52;
w = x + t;
t = w - t;
if (ix < 0x3ff00000) {
if ((ix | lx) == 0)
return (x);
else
return ((hx < 0)? -one : zero);
}
return ((t <= x)? t : t - one);
}