Add libgmp 6.2.0 to third_party
Don't build it yet. That will come in the next review.
Change-Id: Idf3266558165e5ab45f4a41c98cc8c838c8244d5
diff --git a/third_party/gmp/mpz/divexact.c b/third_party/gmp/mpz/divexact.c
new file mode 100644
index 0000000..8336819
--- /dev/null
+++ b/third_party/gmp/mpz/divexact.c
@@ -0,0 +1,89 @@
+/* mpz_divexact -- finds quotient when known that quot * den == num && den != 0.
+
+Contributed to the GNU project by Niels Möller.
+
+Copyright 1991, 1993-1998, 2000-2002, 2005-2007, 2009, 2012 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"
+
+void
+mpz_divexact (mpz_ptr quot, mpz_srcptr num, mpz_srcptr den)
+{
+ mp_ptr qp;
+ mp_size_t qn;
+ mp_srcptr np, dp;
+ mp_size_t nn, dn;
+ TMP_DECL;
+
+#if WANT_ASSERT
+ {
+ mpz_t rem;
+ mpz_init (rem);
+ mpz_tdiv_r (rem, num, den);
+ ASSERT (SIZ(rem) == 0);
+ mpz_clear (rem);
+ }
+#endif
+
+ nn = ABSIZ (num);
+ dn = ABSIZ (den);
+
+ if (nn < dn)
+ {
+ /* This special case avoids segfaults below when the function is
+ incorrectly called with |N| < |D|, N != 0. It also handles the
+ well-defined case N = 0. */
+ SIZ(quot) = 0;
+ return;
+ }
+
+ qn = nn - dn + 1;
+
+ TMP_MARK;
+
+ if (quot == num || quot == den)
+ qp = TMP_ALLOC_LIMBS (qn);
+ else
+ qp = MPZ_NEWALLOC (quot, qn);
+
+ np = PTR(num);
+ dp = PTR(den);
+
+ mpn_divexact (qp, np, nn, dp, dn);
+ MPN_NORMALIZE (qp, qn);
+
+ if (qp != PTR(quot))
+ MPN_COPY (MPZ_NEWALLOC (quot, qn), qp, qn);
+
+ SIZ(quot) = (SIZ(num) ^ SIZ(den)) >= 0 ? qn : -qn;
+
+ TMP_FREE;
+}