os/ossrv/genericopenlibs/cstdlib/LMATH/S_FABS.C
author sl
Tue, 10 Jun 2014 14:32:02 +0200
changeset 1 260cb5ec6c19
permissions -rw-r--r--
Update contrib.
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/* S_FABS.C
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 * 
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 * Portions Copyright (c) 1993-2005 Nokia Corporation and/or its subsidiary(-ies).
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 * All rights reserved.
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 */
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/* @(#)s_fabs.c 5.1 93/09/24 */
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/*
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 * ====================================================
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 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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 *
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 * Developed at SunPro, a Sun Microsystems, Inc. business.
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 * Permission to use, copy, modify, and distribute this
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 * software is freely granted, provided that this notice 
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 * is preserved.
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 * ====================================================
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 */
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/*
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FUNCTION
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       <<fabs>>, <<fabsf>>---absolute value (magnitude)
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INDEX
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	fabs
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INDEX
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	fabsf
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ANSI_SYNOPSIS
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	#include <math.h>
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       double fabs(double <[x]>);
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       float fabsf(float <[x]>);
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TRAD_SYNOPSIS
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	#include <math.h>
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       double fabs(<[x]>) 
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       double <[x]>;
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       float fabsf(<[x]>)
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       float <[x]>;
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DESCRIPTION
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<<fabs>> and <<fabsf>> calculate 
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@tex
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$|x|$, 
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@end tex
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the absolute value (magnitude) of the argument <[x]>, by direct
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manipulation of the bit representation of <[x]>.
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RETURNS
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The calculated value is returned.  No errors are detected.
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PORTABILITY
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<<fabs>> is ANSI.
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<<fabsf>> is an extension.
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*/
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/*
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 * fabs(x) returns the absolute value of x.
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 */
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#include "FDLIBM.H"
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/**
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Return absolute value of floating-point.
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Returns the absoulte value of parameter x. /x/ 
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@return Absoulte value of x.
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@param x Floating point value.
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*/
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EXPORT_C double fabs(double x) __SOFTFP
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{
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	__uint32_t high;
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	GET_HIGH_WORD(high,x);
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	SET_HIGH_WORD(x,high&0x7fffffff);
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        return x;
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}