/* Emulation for ldexpl.
Contributed by Paolo Bonzini
Copyright 2002, 2003 Free Software Foundation, Inc.
This file is part of gnulib.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#include <float.h>
#include <math.h>
#include "mathl.h"
long double
ldexpl(long double x, int exp)
{
long double factor;
int bit;
/* Check for zero, nan and infinity. */
if (x != x || x + x == x )
return x;
if (exp < 0)
{
exp = -exp;
factor = 0.5L;
}
else
factor = 2.0L;
for (bit = 1; bit <= exp; bit <<= 1, factor *= factor)
if (exp & bit)
x *= factor;
return x;
}
#if 0
int
main (void)
{
long double x;
int y;
for (y = 0; y < 29; y++)
printf ("%5d %.16Lg %.16Lg\n", y, ldexpl(0.8L, y), ldexpl(0.8L, -y) * ldexpl(0.8L, y));
}
#endif
