Revert "Remove gmp from AOS"
This reverts commit f37c97684f0910a3f241394549392f00145ab0f7.
We need gmp for SymEngine for symbolicmanipultion in C++
Change-Id: Ia13216d1715cf96944f7b4f422b7a799f921d4a4
Signed-off-by: Austin Schuh <austin.linux@gmail.com>
diff --git a/third_party/gmp/mpn/generic/divis.c b/third_party/gmp/mpn/generic/divis.c
new file mode 100644
index 0000000..f989ddb
--- /dev/null
+++ b/third_party/gmp/mpn/generic/divis.c
@@ -0,0 +1,194 @@
+/* mpn_divisible_p -- mpn by mpn divisibility test
+
+ THE FUNCTIONS IN THIS FILE ARE FOR INTERNAL USE ONLY. THEY'RE ALMOST
+ CERTAIN TO BE SUBJECT TO INCOMPATIBLE CHANGES OR DISAPPEAR COMPLETELY IN
+ FUTURE GNU MP RELEASES.
+
+Copyright 2001, 2002, 2005, 2009, 2014, 2017, 2018 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"
+
+
+/* Determine whether A={ap,an} is divisible by D={dp,dn}. Must have both
+ operands normalized, meaning high limbs non-zero, except that an==0 is
+ allowed.
+
+ There usually won't be many low zero bits on D, but the checks for this
+ are fast and might pick up a few operand combinations, in particular they
+ might reduce D to fit the single-limb mod_1/modexact_1 code.
+
+ Future:
+
+ Getting the remainder limb by limb would make an early exit possible on
+ finding a non-zero. This would probably have to be bdivmod style so
+ there's no addback, but it would need a multi-precision inverse and so
+ might be slower than the plain method (on small sizes at least).
+
+ When D must be normalized (shifted to low bit set), it's possible to
+ suppress the bit-shifting of A down, as long as it's already been checked
+ that A has at least as many trailing zero bits as D. */
+
+int
+mpn_divisible_p (mp_srcptr ap, mp_size_t an,
+ mp_srcptr dp, mp_size_t dn)
+{
+ mp_limb_t alow, dlow, dmask;
+ mp_ptr qp, rp, tp;
+ mp_limb_t di;
+ unsigned twos;
+ int c;
+ TMP_DECL;
+
+ ASSERT (an >= 0);
+ ASSERT (an == 0 || ap[an-1] != 0);
+ ASSERT (dn >= 1);
+ ASSERT (dp[dn-1] != 0);
+ ASSERT_MPN (ap, an);
+ ASSERT_MPN (dp, dn);
+
+ /* When a<d only a==0 is divisible.
+ Notice this test covers all cases of an==0. */
+ if (an < dn)
+ return (an == 0);
+
+ /* Strip low zero limbs from d, requiring a==0 on those. */
+ for (;;)
+ {
+ alow = *ap;
+ dlow = *dp;
+
+ if (dlow != 0)
+ break;
+
+ if (alow != 0)
+ return 0; /* a has fewer low zero limbs than d, so not divisible */
+
+ /* a!=0 and d!=0 so won't get to n==0 */
+ an--; ASSERT (an >= 1);
+ dn--; ASSERT (dn >= 1);
+ ap++;
+ dp++;
+ }
+
+ /* a must have at least as many low zero bits as d */
+ dmask = LOW_ZEROS_MASK (dlow);
+ if ((alow & dmask) != 0)
+ return 0;
+
+ if (dn == 1)
+ {
+ if (ABOVE_THRESHOLD (an, BMOD_1_TO_MOD_1_THRESHOLD))
+ return mpn_mod_1 (ap, an, dlow) == 0;
+
+ count_trailing_zeros (twos, dlow);
+ dlow >>= twos;
+ return mpn_modexact_1_odd (ap, an, dlow) == 0;
+ }
+
+ count_trailing_zeros (twos, dlow);
+ if (dn == 2)
+ {
+ mp_limb_t dsecond = dp[1];
+ if (dsecond <= dmask)
+ {
+ dlow = (dlow >> twos) | (dsecond << (GMP_NUMB_BITS-twos));
+ ASSERT_LIMB (dlow);
+ return MPN_MOD_OR_MODEXACT_1_ODD (ap, an, dlow) == 0;
+ }
+ }
+
+ /* Should we compute Q = A * D^(-1) mod B^k,
+ R = A - Q * D mod B^k
+ here, for some small values of k? Then check if R = 0 (mod B^k). */
+
+ /* We could also compute A' = A mod T and D' = D mod P, for some
+ P = 3 * 5 * 7 * 11 ..., and then check if any prime factor from P
+ dividing D' also divides A'. */
+
+ TMP_MARK;
+
+ TMP_ALLOC_LIMBS_2 (rp, an + 1,
+ qp, an - dn + 1); /* FIXME: Could we avoid this? */
+
+ if (twos != 0)
+ {
+ tp = TMP_ALLOC_LIMBS (dn);
+ ASSERT_NOCARRY (mpn_rshift (tp, dp, dn, twos));
+ dp = tp;
+
+ ASSERT_NOCARRY (mpn_rshift (rp, ap, an, twos));
+ }
+ else
+ {
+ MPN_COPY (rp, ap, an);
+ }
+ if (rp[an - 1] >= dp[dn - 1])
+ {
+ rp[an] = 0;
+ an++;
+ }
+ else if (an == dn)
+ {
+ TMP_FREE;
+ return 0;
+ }
+
+ ASSERT (an > dn); /* requirement of functions below */
+
+ if (BELOW_THRESHOLD (dn, DC_BDIV_QR_THRESHOLD) ||
+ BELOW_THRESHOLD (an - dn, DC_BDIV_QR_THRESHOLD))
+ {
+ binvert_limb (di, dp[0]);
+ mpn_sbpi1_bdiv_qr (qp, rp, an, dp, dn, -di);
+ rp += an - dn;
+ }
+ else if (BELOW_THRESHOLD (dn, MU_BDIV_QR_THRESHOLD))
+ {
+ binvert_limb (di, dp[0]);
+ mpn_dcpi1_bdiv_qr (qp, rp, an, dp, dn, -di);
+ rp += an - dn;
+ }
+ else
+ {
+ tp = TMP_ALLOC_LIMBS (mpn_mu_bdiv_qr_itch (an, dn));
+ mpn_mu_bdiv_qr (qp, rp, rp, an, dp, dn, tp);
+ }
+
+ /* In general, bdiv may return either R = 0 or R = D when D divides
+ A. But R = 0 can happen only when A = 0, which we already have
+ excluded. Furthermore, R == D (mod B^{dn}) implies no carry, so
+ we don't need to check the carry returned from bdiv. */
+
+ MPN_CMP (c, rp, dp, dn);
+
+ TMP_FREE;
+ return c == 0;
+}