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/* mpfr_get_uj -- convert a MPFR number to a huge machine unsigned integer
Copyright 2004, 2006-2020 Free Software Foundation, Inc.
Contributed by the AriC and Caramba projects, INRIA.
This file is part of the GNU MPFR Library.
The GNU MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 3 of the License, or (at your
option) any later version.
The GNU 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 Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
https://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
#define MPFR_NEED_INTMAX_H
#include "mpfr-impl.h"
#ifdef _MPFR_H_HAVE_INTMAX_T
uintmax_t
mpfr_get_uj (mpfr_srcptr f, mpfr_rnd_t rnd)
{
uintmax_t r;
mpfr_prec_t prec;
mpfr_t x;
MPFR_SAVE_EXPO_DECL (expo);
if (MPFR_UNLIKELY (!mpfr_fits_uintmax_p (f, rnd)))
{
MPFR_SET_ERANGEFLAG ();
return MPFR_IS_NAN (f) || MPFR_IS_NEG (f) ?
(uintmax_t) 0 : UINTMAX_MAX;
}
if (MPFR_IS_ZERO (f))
return (uintmax_t) 0;
/* determine the precision of uintmax_t */
for (r = UINTMAX_MAX, prec = 0; r != 0; r /= 2, prec++)
{ }
MPFR_ASSERTD (r == 0);
MPFR_SAVE_EXPO_MARK (expo);
mpfr_init2 (x, prec);
mpfr_rint (x, f, rnd);
MPFR_ASSERTN (MPFR_IS_FP (x));
/* The flags from mpfr_rint are the wanted ones. In particular,
it sets the inexact flag when necessary. */
MPFR_SAVE_EXPO_UPDATE_FLAGS (expo, __gmpfr_flags);
if (MPFR_NOTZERO (x))
{
mp_limb_t *xp;
int sh, n; /* An int should be sufficient in this context. */
MPFR_ASSERTN (MPFR_IS_POS (x));
xp = MPFR_MANT (x);
sh = MPFR_GET_EXP (x);
MPFR_ASSERTN ((mpfr_prec_t) sh <= prec);
for (n = MPFR_LIMB_SIZE(x) - 1; n >= 0; n--)
{
sh -= GMP_NUMB_BITS;
r += (sh >= 0
? (uintmax_t) xp[n] << sh
: (uintmax_t) xp[n] >> (- sh));
}
}
mpfr_clear (x);
MPFR_SAVE_EXPO_FREE (expo);
return r;
}
#endif
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