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/divis_ui.c b/third_party/gmp/mpz/divis_ui.c
new file mode 100644
index 0000000..b24c7dc
--- /dev/null
+++ b/third_party/gmp/mpz/divis_ui.c
@@ -0,0 +1,80 @@
+/* mpz_divisible_ui_p -- mpz by ulong divisibility test.
+
+Copyright 2000-2002 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"
+
+
+int
+mpz_divisible_ui_p (mpz_srcptr a, unsigned long d)
+{
+ mp_size_t asize;
+ mp_ptr ap;
+ unsigned twos;
+
+ asize = SIZ(a);
+ if (UNLIKELY (d == 0))
+ return (asize == 0);
+
+ if (asize == 0) /* 0 divisible by any d */
+ return 1;
+
+ /* For nails don't try to be clever if d is bigger than a limb, just fake
+ up an mpz_t and go to the main mpz_divisible_p. */
+ if (d > GMP_NUMB_MAX)
+ {
+ mp_limb_t dlimbs[2];
+ mpz_t dz;
+ ALLOC(dz) = 2;
+ PTR(dz) = dlimbs;
+ mpz_set_ui (dz, d);
+ return mpz_divisible_p (a, dz);
+ }
+
+ ap = PTR(a);
+ asize = ABS(asize); /* ignore sign of a */
+
+ if (ABOVE_THRESHOLD (asize, BMOD_1_TO_MOD_1_THRESHOLD))
+ return mpn_mod_1 (ap, asize, (mp_limb_t) d) == 0;
+
+ if (! (d & 1))
+ {
+ /* Strip low zero bits to get odd d required by modexact. If d==e*2^n
+ and a is divisible by 2^n and by e, then it's divisible by d. */
+
+ if ((ap[0] & LOW_ZEROS_MASK (d)) != 0)
+ return 0;
+
+ count_trailing_zeros (twos, (mp_limb_t) d);
+ d >>= twos;
+ }
+
+ return mpn_modexact_1_odd (ap, asize, (mp_limb_t) d) == 0;
+}