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/mpf/fits_u.h b/third_party/gmp/mpf/fits_u.h
new file mode 100644
index 0000000..bd7ca78
--- /dev/null
+++ b/third_party/gmp/mpf/fits_u.h
@@ -0,0 +1,73 @@
+/* mpf_fits_u*_p -- test whether an mpf fits a C unsigned type.
+
+Copyright 2001, 2002, 2013, 2014 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"
+
+
+/* Notice this is equivalent to mpz_set_f + mpz_fits_u*_p.  */
+
+int
+FUNCTION (mpf_srcptr f) __GMP_NOTHROW
+{
+  mp_size_t  fn;
+  mp_srcptr  fp;
+  mp_exp_t   exp;
+  mp_limb_t  fl;
+
+  exp = EXP(f);
+  if (exp < 1)
+    return 1;  /* -1 < f < 1 truncates to zero, so fits */
+
+  fn = SIZ(f);
+  if (fn < 0) /* zero catched by exp == 0 */
+    return 0; /* negatives don't fit */
+
+  fp = PTR(f);
+
+  if (exp == 1)
+    {
+      fl = fp[fn-1];
+    }
+#if GMP_NAIL_BITS != 0
+  else if (exp == 2 && MAXIMUM > GMP_NUMB_MAX)
+    {
+      fl = fp[fn-1];
+      if ((fl >> GMP_NAIL_BITS) != 0)
+	return 0;
+      fl = (fl << GMP_NUMB_BITS);
+      if (fn >= 2)
+        fl |= fp[fn-2];
+    }
+#endif
+  else
+    return 0;
+
+  return fl <= MAXIMUM;
+}