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-rw-r--r--gmp-6.3.0/mpn/generic/divrem.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/gmp-6.3.0/mpn/generic/divrem.c b/gmp-6.3.0/mpn/generic/divrem.c
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+/* mpn_divrem -- Divide natural numbers, producing both remainder and
+ quotient. This is now just a middle layer calling mpn_tdiv_qr.
+
+Copyright 1993-1997, 1999-2002, 2005, 2016 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of either:
+
+ * 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.
+
+or
+
+ * the GNU General Public License as published by the Free Software
+ Foundation; either version 2 of the License, or (at your option) any
+ later version.
+
+or both in parallel, as here.
+
+The GNU MP 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 General Public License
+for more details.
+
+You should have received copies of the GNU General Public License and the
+GNU Lesser General Public License along with the GNU MP Library. If not,
+see https://www.gnu.org/licenses/. */
+
+#include "gmp-impl.h"
+#include "longlong.h"
+
+mp_limb_t
+mpn_divrem (mp_ptr qp, mp_size_t qxn,
+ mp_ptr np, mp_size_t nn,
+ mp_srcptr dp, mp_size_t dn)
+{
+ ASSERT (qxn >= 0);
+ ASSERT (nn >= dn);
+ ASSERT (dn >= 1);
+ ASSERT (dp[dn-1] & GMP_NUMB_HIGHBIT);
+ ASSERT (! MPN_OVERLAP_P (np, nn, dp, dn));
+ ASSERT (! MPN_OVERLAP_P (qp, nn-dn+qxn, np, nn) || qp==np+dn+qxn);
+ ASSERT (! MPN_OVERLAP_P (qp, nn-dn+qxn, dp, dn));
+ ASSERT_MPN (np, nn);
+ ASSERT_MPN (dp, dn);
+
+ if (dn == 1)
+ {
+ mp_limb_t ret;
+ mp_ptr q2p;
+ mp_size_t qn;
+ TMP_DECL;
+
+ TMP_MARK;
+ q2p = TMP_ALLOC_LIMBS (nn + qxn);
+
+ np[0] = mpn_divrem_1 (q2p, qxn, np, nn, dp[0]);
+ qn = nn + qxn - 1;
+ MPN_COPY (qp, q2p, qn);
+ ret = q2p[qn];
+
+ TMP_FREE;
+ return ret;
+ }
+ else if (dn == 2)
+ {
+ return mpn_divrem_2 (qp, qxn, np, nn, dp);
+ }
+ else
+ {
+ mp_ptr q2p;
+ mp_limb_t qhl;
+ mp_size_t qn;
+ TMP_DECL;
+
+ TMP_MARK;
+ if (UNLIKELY (qxn != 0))
+ {
+ mp_ptr n2p;
+ TMP_ALLOC_LIMBS_2 (n2p, nn + qxn,
+ q2p, nn - dn + qxn + 1);
+ MPN_ZERO (n2p, qxn);
+ MPN_COPY (n2p + qxn, np, nn);
+ mpn_tdiv_qr (q2p, np, 0L, n2p, nn + qxn, dp, dn);
+ qn = nn - dn + qxn;
+ MPN_COPY (qp, q2p, qn);
+ qhl = q2p[qn];
+ }
+ else
+ {
+ q2p = TMP_ALLOC_LIMBS (nn - dn + 1);
+ mpn_tdiv_qr (q2p, np, 0L, np, nn, dp, dn);
+ qn = nn - dn;
+ MPN_COPY (qp, q2p, qn);
+ qhl = q2p[qn];
+ }
+ TMP_FREE;
+ return qhl;
+ }
+}