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/* s_frexpf.c -- float version of s_frexp.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* 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.
* ====================================================
*/
#ifndef lint
static char rcsid[] = "$FreeBSD: src/lib/msun/src/s_frexpf.c,v 1.8 2002/05/28 18:15:04 alfred Exp $";
#endif
#include "math.h"
#include "math_private.h"
static const float
two25 = 3.3554432000e+07; /* 0x4c000000 */
float
frexpf(float x, int *eptr)
{
int32_t hx,ix;
GET_FLOAT_WORD(hx,x);
ix = 0x7fffffff&hx;
*eptr = 0;
if(ix>=0x7f800000||(ix==0)) return x; /* 0,inf,nan */
if (ix<0x00800000) { /* subnormal */
x *= two25;
GET_FLOAT_WORD(hx,x);
ix = hx&0x7fffffff;
*eptr = -25;
}
*eptr += (ix>>23)-126;
hx = (hx&0x807fffff)|0x3f000000;
SET_FLOAT_WORD(x,hx);
return x;
}
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