significand.c revision 1ec68d336ba97cd53f46053ac10401d16014d075
/*
* 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 significand = __significand
#include "libm.h"
double
significand(double x) {
int ix = ((int *) &x)[HIWORD] & ~0x80000000;
/* weed out 0/+-Inf/NaN because C99 ilogb raises invalid on them */
if ((ix | ((int *) &x)[LOWORD]) == 0 || ix >= 0x7ff00000)
#if defined(FPADD_TRAPS_INCOMPLETE_ON_NAN)
return ((ix & 0x80000) != 0 ? x : x + x);
/* assumes sparc-like QNaN */
#else
return (x + x);
#endif
else
return (scalbn(x, -ilogb(x)));
}