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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 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "@(#)scalbl.c 1.8 06/01/31 SMI"
#pragma weak scalbl = __scalbl
/*
* scalbl(x,n): return x * 2**n by manipulating exponent.
*/
#include "libm.h"
#include "longdouble.h"
long double
scalbl(long double x, long double fn) {
int *py = (int *) &fn, n;
long double z;
if (isnanl(x) || isnanl(fn))
return x * fn;
/* fn is +/-Inf */
#if !defined(__i386)
if ((py[0] & 0x7fff0000) == 0x7fff0000)
if ((py[0] & 0x80000000) != 0)
#else
if ((py[2] & 0x7fff) == 0x7fff)
if ((py[2] & 0x8000) != 0)
#endif
return x / (-fn);
else
return x * fn;
if (rintl(fn) != fn)
return (fn - fn) / (fn - fn);
if (fn > 65000.0L)
z = scalbnl(x, 65000);
else if (-fn > 65000.0L)
z = scalbnl(x, -65000);
else {
n = (int) fn;
z = scalbnl(x, n);
}
return z;
}
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