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-rw-r--r--Build/source/libs/gmp/gmp-6.0.0/mpn/generic/mulmid.c256
1 files changed, 256 insertions, 0 deletions
diff --git a/Build/source/libs/gmp/gmp-6.0.0/mpn/generic/mulmid.c b/Build/source/libs/gmp/gmp-6.0.0/mpn/generic/mulmid.c
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index 00000000000..6b4ea3253dc
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+++ b/Build/source/libs/gmp/gmp-6.0.0/mpn/generic/mulmid.c
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+/* mpn_mulmid -- middle product
+
+ Contributed by David Harvey.
+
+ THE FUNCTION IN THIS FILE IS INTERNAL WITH A MUTABLE INTERFACE. IT IS ONLY
+ SAFE TO REACH IT THROUGH DOCUMENTED INTERFACES. IN FACT, IT IS ALMOST
+ GUARANTEED THAT IT'LL CHANGE OR DISAPPEAR IN A FUTURE GNU MP RELEASE.
+
+Copyright 2011 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.h"
+#include "gmp-impl.h"
+
+
+#define CHUNK (200 + MULMID_TOOM42_THRESHOLD)
+
+
+void
+mpn_mulmid (mp_ptr rp,
+ mp_srcptr ap, mp_size_t an,
+ mp_srcptr bp, mp_size_t bn)
+{
+ mp_size_t rn, k;
+ mp_ptr scratch, temp;
+
+ ASSERT (an >= bn);
+ ASSERT (bn >= 1);
+ ASSERT (! MPN_OVERLAP_P (rp, an - bn + 3, ap, an));
+ ASSERT (! MPN_OVERLAP_P (rp, an - bn + 3, bp, bn));
+
+ if (bn < MULMID_TOOM42_THRESHOLD)
+ {
+ /* region not tall enough to make toom42 worthwhile for any portion */
+
+ if (an < CHUNK)
+ {
+ /* region not too wide either, just call basecase directly */
+ mpn_mulmid_basecase (rp, ap, an, bp, bn);
+ return;
+ }
+
+ /* Region quite wide. For better locality, use basecase on chunks:
+
+ AAABBBCC..
+ .AAABBBCC.
+ ..AAABBBCC
+ */
+
+ k = CHUNK - bn + 1; /* number of diagonals per chunk */
+
+ /* first chunk (marked A in the above diagram) */
+ mpn_mulmid_basecase (rp, ap, CHUNK, bp, bn);
+
+ /* remaining chunks (B, C, etc) */
+ an -= k;
+
+ while (an >= CHUNK)
+ {
+ mp_limb_t t0, t1, cy;
+ ap += k, rp += k;
+ t0 = rp[0], t1 = rp[1];
+ mpn_mulmid_basecase (rp, ap, CHUNK, bp, bn);
+ ADDC_LIMB (cy, rp[0], rp[0], t0); /* add back saved limbs */
+ MPN_INCR_U (rp + 1, k + 1, t1 + cy);
+ an -= k;
+ }
+
+ if (an >= bn)
+ {
+ /* last remaining chunk */
+ mp_limb_t t0, t1, cy;
+ ap += k, rp += k;
+ t0 = rp[0], t1 = rp[1];
+ mpn_mulmid_basecase (rp, ap, an, bp, bn);
+ ADDC_LIMB (cy, rp[0], rp[0], t0);
+ MPN_INCR_U (rp + 1, an - bn + 2, t1 + cy);
+ }
+
+ return;
+ }
+
+ /* region is tall enough for toom42 */
+
+ rn = an - bn + 1;
+
+ if (rn < MULMID_TOOM42_THRESHOLD)
+ {
+ /* region not wide enough to make toom42 worthwhile for any portion */
+
+ TMP_DECL;
+
+ if (bn < CHUNK)
+ {
+ /* region not too tall either, just call basecase directly */
+ mpn_mulmid_basecase (rp, ap, an, bp, bn);
+ return;
+ }
+
+ /* Region quite tall. For better locality, use basecase on chunks:
+
+ AAAAA....
+ .AAAAA...
+ ..BBBBB..
+ ...BBBBB.
+ ....CCCCC
+ */
+
+ TMP_MARK;
+
+ temp = TMP_ALLOC_LIMBS (rn + 2);
+
+ /* first chunk (marked A in the above diagram) */
+ bp += bn - CHUNK, an -= bn - CHUNK;
+ mpn_mulmid_basecase (rp, ap, an, bp, CHUNK);
+
+ /* remaining chunks (B, C, etc) */
+ bn -= CHUNK;
+
+ while (bn >= CHUNK)
+ {
+ ap += CHUNK, bp -= CHUNK;
+ mpn_mulmid_basecase (temp, ap, an, bp, CHUNK);
+ mpn_add_n (rp, rp, temp, rn + 2);
+ bn -= CHUNK;
+ }
+
+ if (bn)
+ {
+ /* last remaining chunk */
+ ap += CHUNK, bp -= bn;
+ mpn_mulmid_basecase (temp, ap, rn + bn - 1, bp, bn);
+ mpn_add_n (rp, rp, temp, rn + 2);
+ }
+
+ TMP_FREE;
+ return;
+ }
+
+ /* we're definitely going to use toom42 somewhere */
+
+ if (bn > rn)
+ {
+ /* slice region into chunks, use toom42 on all chunks except possibly
+ the last:
+
+ AA....
+ .AA...
+ ..BB..
+ ...BB.
+ ....CC
+ */
+
+ TMP_DECL;
+ TMP_MARK;
+
+ temp = TMP_ALLOC_LIMBS (rn + 2 + mpn_toom42_mulmid_itch (rn));
+ scratch = temp + rn + 2;
+
+ /* first chunk (marked A in the above diagram) */
+ bp += bn - rn;
+ mpn_toom42_mulmid (rp, ap, bp, rn, scratch);
+
+ /* remaining chunks (B, C, etc) */
+ bn -= rn;
+
+ while (bn >= rn)
+ {
+ ap += rn, bp -= rn;
+ mpn_toom42_mulmid (temp, ap, bp, rn, scratch);
+ mpn_add_n (rp, rp, temp, rn + 2);
+ bn -= rn;
+ }
+
+ if (bn)
+ {
+ /* last remaining chunk */
+ ap += rn, bp -= bn;
+ mpn_mulmid (temp, ap, rn + bn - 1, bp, bn);
+ mpn_add_n (rp, rp, temp, rn + 2);
+ }
+
+ TMP_FREE;
+ }
+ else
+ {
+ /* slice region into chunks, use toom42 on all chunks except possibly
+ the last:
+
+ AAABBBCC..
+ .AAABBBCC.
+ ..AAABBBCC
+ */
+
+ TMP_DECL;
+ TMP_MARK;
+
+ scratch = TMP_ALLOC_LIMBS (mpn_toom42_mulmid_itch (bn));
+
+ /* first chunk (marked A in the above diagram) */
+ mpn_toom42_mulmid (rp, ap, bp, bn, scratch);
+
+ /* remaining chunks (B, C, etc) */
+ rn -= bn;
+
+ while (rn >= bn)
+ {
+ mp_limb_t t0, t1, cy;
+ ap += bn, rp += bn;
+ t0 = rp[0], t1 = rp[1];
+ mpn_toom42_mulmid (rp, ap, bp, bn, scratch);
+ ADDC_LIMB (cy, rp[0], rp[0], t0); /* add back saved limbs */
+ MPN_INCR_U (rp + 1, bn + 1, t1 + cy);
+ rn -= bn;
+ }
+
+ TMP_FREE;
+
+ if (rn)
+ {
+ /* last remaining chunk */
+ mp_limb_t t0, t1, cy;
+ ap += bn, rp += bn;
+ t0 = rp[0], t1 = rp[1];
+ mpn_mulmid (rp, ap, rn + bn - 1, bp, bn);
+ ADDC_LIMB (cy, rp[0], rp[0], t0);
+ MPN_INCR_U (rp + 1, rn + 1, t1 + cy);
+ }
+ }
+}