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//===========================================================================
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//
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//      s_frexp.c
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//
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//      Part of the standard mathematical function library
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//
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//===========================================================================
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//####ECOSGPLCOPYRIGHTBEGIN####
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// -------------------------------------------
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// This file is part of eCos, the Embedded Configurable Operating System.
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// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
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//
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// eCos is free software; you can redistribute it and/or modify it under
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// the terms of the GNU General Public License as published by the Free
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// Software Foundation; either version 2 or (at your option) any later version.
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//
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// eCos is distributed in the hope that it will be useful, but WITHOUT ANY
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// WARRANTY; without even the implied warranty of MERCHANTABILITY or
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// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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// for more details.
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//
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// You should have received a copy of the GNU General Public License along
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// with eCos; if not, write to the Free Software Foundation, Inc.,
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// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
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//
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// As a special exception, if other files instantiate templates or use macros
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// or inline functions from this file, or you compile this file and link it
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// with other works to produce a work based on this file, this file does not
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// by itself cause the resulting work to be covered by the GNU General Public
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// License. However the source code for this file must still be made available
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// in accordance with section (3) of the GNU General Public License.
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//
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// This exception does not invalidate any other reasons why a work based on
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// this file might be covered by the GNU General Public License.
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//
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// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
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// at http://sources.redhat.com/ecos/ecos-license/
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// -------------------------------------------
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//####ECOSGPLCOPYRIGHTEND####
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//===========================================================================
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//#####DESCRIPTIONBEGIN####
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//
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// Author(s):   jlarmour
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// Contributors:  jlarmour
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// Date:        1998-02-13
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// Purpose:     
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// Description: 
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// Usage:       
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//
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//####DESCRIPTIONEND####
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//
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//===========================================================================
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// CONFIGURATION
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#include <pkgconf/libm.h>   // Configuration header
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// Include the Math library?
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#ifdef CYGPKG_LIBM     
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// Derived from code with the following copyright
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/* @(#)s_frexp.c 1.4 95/01/18 */
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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 SunSoft, 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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 * for non-zero x
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 *      x = frexp(arg,&exp);
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 * return a double fp quantity x such that 0.5 <= |x| <1.0
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 * and the corresponding binary exponent "exp". That is
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 *      arg = x*2^exp.
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 * If arg is inf, 0.0, or NaN, then frexp(arg,&exp) returns arg
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 * with *exp=0.
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 */
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#include "mathincl/fdlibm.h"
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static const double
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two54 =  1.80143985094819840000e+16; /* 0x43500000, 0x00000000 */
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        double frexp(double x, int *eptr)
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{
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        int  hx, ix, lx;
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        hx = CYG_LIBM_HI(x);
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        ix = 0x7fffffff&hx;
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        lx = CYG_LIBM_LO(x);
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        *eptr = 0;
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        if(ix>=0x7ff00000||((ix|lx)==0)) return x;      /* 0,inf,nan */
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        if (ix<0x00100000) {            /* subnormal */
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            x *= two54;
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            hx = CYG_LIBM_HI(x);
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            ix = hx&0x7fffffff;
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            *eptr = -54;
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        }
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        *eptr += (ix>>20)-1022;
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        hx = (hx&0x800fffff)|0x3fe00000;
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        CYG_LIBM_HI(x) = hx;
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        return x;
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}
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#endif // ifdef CYGPKG_LIBM     
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// EOF s_frexp.c

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