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/*
* 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.
*/
#pragma weak __rint = rint
/*
* rint(x) return x rounded to integral according to the rounding direction
* rint(x) returns result with the same sign as x's, including 0.0.
*/
#include "libm.h"
#if defined(__i386) && !defined(__amd64) && (!defined(__FLT_EVAL_METHOD__) || \
__FLT_EVAL_METHOD__ != 0)
extern enum fp_precision_type __swapRP(enum fp_precision_type);
#define DECLRP(x) enum fp_precision_type x;
#define SWAPRP(new, x) x = __swapRP(new);
#define RESTRP(x) (void) __swapRP(x);
#else
#define DECLRP(x)
#define SWAPRP(new, x)
#define RESTRP(x)
#endif
static const double
two52 = 4503599627370496.0,
zero = 0.0,
one = 1.0;
double
rint(double x) {
DECLRP(rp)
double t, w;
int ix, hx;
ix = ((int *)&x)[HIWORD];
hx = ix & ~0x80000000;
if (hx >= 0x43300000)
return (x * one);
t = (ix < 0)? -two52 : two52;
SWAPRP(fp_double, rp) /* set precision mode to double */
w = x + t; /* x+sign(x)*2**52 rounded */
RESTRP(rp) /* restore precision mode */
if (w == t)
return ((ix < 0)? -zero : zero);
return (w - t);
}
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