/*
Copyright (C) 2009 William Hart
Copyright (C) 2011 Fredrik Johansson
This file is part of FLINT.
FLINT is free software: you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License (LGPL) as published
by the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version. See .
*/
#include
#include "flint.h"
#include "ulong_extras.h"
#include "fmpz.h"
void fmpz_cdiv_q_2exp(fmpz_t f, const fmpz_t g, ulong exp)
{
fmpz d = *g;
if (!COEFF_IS_MPZ(d)) /* g is small */
{
fmpz_set_si(f, -((-d) >> FLINT_MIN(exp, FLINT_BITS - 2)));
}
else /*g is large */
{
__mpz_struct * mpz_ptr = _fmpz_promote(f); /* g is already large */
mpz_cdiv_q_2exp(mpz_ptr, COEFF_TO_PTR(d), exp);
_fmpz_demote_val(f); /* division may make value small */
}
}