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/*
Copyright (C) 2014 Fredrik Johansson
This file is part of Arb.
Arb 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 <http://www.gnu.org/licenses/>.
*/
#include "mag.h"
void
mag_div(mag_t z, const mag_t x, const mag_t y)
{
if (mag_is_special(x) || mag_is_special(y))
{
if (mag_is_zero(y) || mag_is_inf(x))
mag_inf(z);
else
mag_zero(z);
}
else
{
mp_limb_t q;
slong fix;
#if FLINT_BITS == 64
q = (MAG_MAN(x) << MAG_BITS) / MAG_MAN(y) + 1;
#else
mp_limb_t hi, lo, r;
lo = MAG_MAN(x) << MAG_BITS;
hi = MAG_MAN(x) >> (FLINT_BITS - MAG_BITS);
udiv_qrnnd(q, r, hi, lo, MAG_MAN(y));
q += 1;
#endif
fix = q >> MAG_BITS;
q = (q >> fix) + fix;
/* could overflow to next power of two */
if (q >> MAG_BITS)
{
q >>= 1;
fix += 1;
}
MAG_MAN(z) = q;
_fmpz_sub2_fast(MAG_EXPREF(z), MAG_EXPREF(x), MAG_EXPREF(y), fix);
}
}
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