genericopenlibs/cstdlib/LMATH/S_FABS.C
author Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
Tue, 02 Feb 2010 02:01:42 +0200
changeset 0 e4d67989cc36
permissions -rw-r--r--
Revision: 201002 Kit: 201005

/* S_FABS.C
 * 
 * Portions Copyright (c) 1993-2005 Nokia Corporation and/or its subsidiary(-ies).
 * All rights reserved.
 */


/* @(#)s_fabs.c 5.1 93/09/24 */
/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunPro, a Sun Microsystems, Inc. business.
 * Permission to use, copy, modify, and distribute this
 * software is freely granted, provided that this notice 
 * is preserved.
 * ====================================================
 */

/*
FUNCTION
       <<fabs>>, <<fabsf>>---absolute value (magnitude)
INDEX
	fabs
INDEX
	fabsf

ANSI_SYNOPSIS
	#include <math.h>
       double fabs(double <[x]>);
       float fabsf(float <[x]>);

TRAD_SYNOPSIS
	#include <math.h>
       double fabs(<[x]>) 
       double <[x]>;

       float fabsf(<[x]>)
       float <[x]>;

DESCRIPTION
<<fabs>> and <<fabsf>> calculate 
@tex
$|x|$, 
@end tex
the absolute value (magnitude) of the argument <[x]>, by direct
manipulation of the bit representation of <[x]>.

RETURNS
The calculated value is returned.  No errors are detected.

PORTABILITY
<<fabs>> is ANSI.
<<fabsf>> is an extension.

*/

/*
 * fabs(x) returns the absolute value of x.
 */

#include "FDLIBM.H"

/**
Return absolute value of floating-point.
Returns the absoulte value of parameter x. /x/ 
@return Absoulte value of x.
@param x Floating point value.
*/
EXPORT_C double fabs(double x) __SOFTFP
{
	__uint32_t high;
	GET_HIGH_WORD(high,x);
	SET_HIGH_WORD(x,high&0x7fffffff);
        return x;
}