|
Packit |
5c3484 |
/* mpn_divrem -- Divide natural numbers, producing both remainder and
|
|
Packit |
5c3484 |
quotient. This is now just a middle layer calling mpn_tdiv_qr.
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
Copyright 1993-1997, 1999-2002, 2005 Free Software Foundation, Inc.
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
This file is part of the GNU MP Library.
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
The GNU MP Library is free software; you can redistribute it and/or modify
|
|
Packit |
5c3484 |
it under the terms of either:
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
* the GNU Lesser General Public License as published by the Free
|
|
Packit |
5c3484 |
Software Foundation; either version 3 of the License, or (at your
|
|
Packit |
5c3484 |
option) any later version.
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
or
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
* the GNU General Public License as published by the Free Software
|
|
Packit |
5c3484 |
Foundation; either version 2 of the License, or (at your option) any
|
|
Packit |
5c3484 |
later version.
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
or both in parallel, as here.
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
The GNU MP Library is distributed in the hope that it will be useful, but
|
|
Packit |
5c3484 |
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
|
Packit |
5c3484 |
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
Packit |
5c3484 |
for more details.
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
You should have received copies of the GNU General Public License and the
|
|
Packit |
5c3484 |
GNU Lesser General Public License along with the GNU MP Library. If not,
|
|
Packit |
5c3484 |
see https://www.gnu.org/licenses/. */
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
#include "gmp.h"
|
|
Packit |
5c3484 |
#include "gmp-impl.h"
|
|
Packit |
5c3484 |
#include "longlong.h"
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
mp_limb_t
|
|
Packit |
5c3484 |
mpn_divrem (mp_ptr qp, mp_size_t qxn,
|
|
Packit |
5c3484 |
mp_ptr np, mp_size_t nn,
|
|
Packit |
5c3484 |
mp_srcptr dp, mp_size_t dn)
|
|
Packit |
5c3484 |
{
|
|
Packit |
5c3484 |
ASSERT (qxn >= 0);
|
|
Packit |
5c3484 |
ASSERT (nn >= dn);
|
|
Packit |
5c3484 |
ASSERT (dn >= 1);
|
|
Packit |
5c3484 |
ASSERT (dp[dn-1] & GMP_NUMB_HIGHBIT);
|
|
Packit |
5c3484 |
ASSERT (! MPN_OVERLAP_P (np, nn, dp, dn));
|
|
Packit |
5c3484 |
ASSERT (! MPN_OVERLAP_P (qp, nn-dn+qxn, np, nn) || qp==np+dn+qxn);
|
|
Packit |
5c3484 |
ASSERT (! MPN_OVERLAP_P (qp, nn-dn+qxn, dp, dn));
|
|
Packit |
5c3484 |
ASSERT_MPN (np, nn);
|
|
Packit |
5c3484 |
ASSERT_MPN (dp, dn);
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
if (dn == 1)
|
|
Packit |
5c3484 |
{
|
|
Packit |
5c3484 |
mp_limb_t ret;
|
|
Packit |
5c3484 |
mp_ptr q2p;
|
|
Packit |
5c3484 |
mp_size_t qn;
|
|
Packit |
5c3484 |
TMP_DECL;
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
TMP_MARK;
|
|
Packit |
5c3484 |
q2p = TMP_ALLOC_LIMBS (nn + qxn);
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
np[0] = mpn_divrem_1 (q2p, qxn, np, nn, dp[0]);
|
|
Packit |
5c3484 |
qn = nn + qxn - 1;
|
|
Packit |
5c3484 |
MPN_COPY (qp, q2p, qn);
|
|
Packit |
5c3484 |
ret = q2p[qn];
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
TMP_FREE;
|
|
Packit |
5c3484 |
return ret;
|
|
Packit |
5c3484 |
}
|
|
Packit |
5c3484 |
else if (dn == 2)
|
|
Packit |
5c3484 |
{
|
|
Packit |
5c3484 |
return mpn_divrem_2 (qp, qxn, np, nn, dp);
|
|
Packit |
5c3484 |
}
|
|
Packit |
5c3484 |
else
|
|
Packit |
5c3484 |
{
|
|
Packit |
5c3484 |
mp_ptr rp, q2p;
|
|
Packit |
5c3484 |
mp_limb_t qhl;
|
|
Packit |
5c3484 |
mp_size_t qn;
|
|
Packit |
5c3484 |
TMP_DECL;
|
|
Packit |
5c3484 |
|
|
Packit |
5c3484 |
TMP_MARK;
|
|
Packit |
5c3484 |
if (UNLIKELY (qxn != 0))
|
|
Packit |
5c3484 |
{
|
|
Packit |
5c3484 |
mp_ptr n2p;
|
|
Packit |
5c3484 |
n2p = TMP_ALLOC_LIMBS (nn + qxn);
|
|
Packit |
5c3484 |
MPN_ZERO (n2p, qxn);
|
|
Packit |
5c3484 |
MPN_COPY (n2p + qxn, np, nn);
|
|
Packit |
5c3484 |
q2p = TMP_ALLOC_LIMBS (nn - dn + qxn + 1);
|
|
Packit |
5c3484 |
rp = TMP_ALLOC_LIMBS (dn);
|
|
Packit |
5c3484 |
mpn_tdiv_qr (q2p, rp, 0L, n2p, nn + qxn, dp, dn);
|
|
Packit |
5c3484 |
MPN_COPY (np, rp, dn);
|
|
Packit |
5c3484 |
qn = nn - dn + qxn;
|
|
Packit |
5c3484 |
MPN_COPY (qp, q2p, qn);
|
|
Packit |
5c3484 |
qhl = q2p[qn];
|
|
Packit |
5c3484 |
}
|
|
Packit |
5c3484 |
else
|
|
Packit |
5c3484 |
{
|
|
Packit |
5c3484 |
q2p = TMP_ALLOC_LIMBS (nn - dn + 1);
|
|
Packit |
5c3484 |
rp = TMP_ALLOC_LIMBS (dn);
|
|
Packit |
5c3484 |
mpn_tdiv_qr (q2p, rp, 0L, np, nn, dp, dn);
|
|
Packit |
5c3484 |
MPN_COPY (np, rp, dn); /* overwrite np area with remainder */
|
|
Packit |
5c3484 |
qn = nn - dn;
|
|
Packit |
5c3484 |
MPN_COPY (qp, q2p, qn);
|
|
Packit |
5c3484 |
qhl = q2p[qn];
|
|
Packit |
5c3484 |
}
|
|
Packit |
5c3484 |
TMP_FREE;
|
|
Packit |
5c3484 |
return qhl;
|
|
Packit |
5c3484 |
}
|
|
Packit |
5c3484 |
}
|