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/mpf/trunc.c b/third_party/gmp/mpf/trunc.c
new file mode 100644
index 0000000..e9af4a7
--- /dev/null
+++ b/third_party/gmp/mpf/trunc.c
@@ -0,0 +1,74 @@
+/* mpf_trunc -- truncate an mpf to an integer.
+
+Copyright 2001 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 the use of prec+1 ensures mpf_trunc is equivalent to mpf_set if u
+ is already an integer. */
+
+void
+mpf_trunc (mpf_ptr r, mpf_srcptr u)
+{
+ mp_ptr rp;
+ mp_srcptr up;
+ mp_size_t size, asize, prec;
+ mp_exp_t exp;
+
+ exp = EXP(u);
+ size = SIZ(u);
+ if (size == 0 || exp <= 0)
+ {
+ /* u is only a fraction */
+ SIZ(r) = 0;
+ EXP(r) = 0;
+ return;
+ }
+
+ up = PTR(u);
+ EXP(r) = exp;
+ asize = ABS (size);
+ up += asize;
+
+ /* skip fraction part of u */
+ asize = MIN (asize, exp);
+
+ /* don't lose precision in the copy */
+ prec = PREC(r) + 1;
+
+ /* skip excess over target precision */
+ asize = MIN (asize, prec);
+
+ up -= asize;
+ rp = PTR(r);
+ SIZ(r) = (size >= 0 ? asize : -asize);
+ if (rp != up)
+ MPN_COPY_INCR (rp, up, asize);
+}