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/* mpfr_set_f -- set a MPFR number from a GNU MPF number
Copyright (C) 1999-2000 PolKA project, Inria Lorraine and Loria
This file is part of the MPFR Library.
The MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
The MPFR Library 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 Library General Public
License for more details.
You should have received a copy of the GNU Library General Public License
along with the MPFR Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include <stdio.h>
#include "gmp.h"
#include "gmp-impl.h"
#include "longlong.h"
#include "mpfr.h"
void
#if __STDC__
mpfr_set_f(mpfr_ptr y, mpf_srcptr x, mp_rnd_t rnd_mode)
#else
mpfr_set_f(y, x, rnd_mode)
mpfr_ptr y;
mpf_srcptr x;
mp_rnd_t rnd_mode;
#endif
{
mp_limb_t *my, *mx, *tmp; unsigned long cnt, sx, sy;
TMP_DECL(marker);
sx = ABS(SIZ(x)); sy = MPFR_ABSSIZE(y);
my = MPFR_MANT(y); mx = MPFR_MANT(x);
if (sx==0) { /* x is zero */
MPFR_SET_ZERO(y); return;
}
count_leading_zeros(cnt, mx[sx - 1]);
if (SIZ(x)*MPFR_SIGN(y)<0) MPFR_CHANGE_SIGN(y);
if (sy < sx)
{
unsigned long xprec = sx * BITS_PER_MP_LIMB;
tmp = (mp_limb_t*) TMP_ALLOC(xprec);
if (cnt) mpn_lshift(tmp, mx, sx, cnt);
else MPN_COPY(tmp, mx, sx);
mpfr_round_raw(my, tmp, xprec, (SIZ(x)<0), MPFR_PREC(y), rnd_mode);
}
else
{
if (cnt) mpn_lshift(my + sy - sx, mx, sx, cnt);
else MPN_COPY(my + sy - sx, mx, sy);
MPN_ZERO(my, sy - sx);
/* no rounding necessary, since y has a larger mantissa */
}
MPFR_EXP(y) = MPFR_EXP(x) * BITS_PER_MP_LIMB - cnt;
TMP_FREE(marker);
}
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