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/cmp.c b/third_party/gmp/mpf/cmp.c
new file mode 100644
index 0000000..3518b51
--- /dev/null
+++ b/third_party/gmp/mpf/cmp.c
@@ -0,0 +1,113 @@
+/* mpf_cmp -- Compare two floats.
+
+Copyright 1993, 1994, 1996, 2001, 2015 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"
+
+int
+mpf_cmp (mpf_srcptr u, mpf_srcptr v) __GMP_NOTHROW
+{
+ mp_srcptr up, vp;
+ mp_size_t usize, vsize;
+ mp_exp_t uexp, vexp;
+ int cmp;
+ int usign;
+
+ usize = SIZ(u);
+ vsize = SIZ(v);
+ usign = usize >= 0 ? 1 : -1;
+
+ /* 1. Are the signs different? */
+ if ((usize ^ vsize) >= 0)
+ {
+ /* U and V are both non-negative or both negative. */
+ if (usize == 0)
+ /* vsize >= 0 */
+ return -(vsize != 0);
+ if (vsize == 0)
+ /* usize >= 0 */
+ return usize != 0;
+ /* Fall out. */
+ }
+ else
+ {
+ /* Either U or V is negative, but not both. */
+ return usign;
+ }
+
+ /* U and V have the same sign and are both non-zero. */
+
+ uexp = EXP(u);
+ vexp = EXP(v);
+
+ /* 2. Are the exponents different? */
+ if (uexp > vexp)
+ return usign;
+ if (uexp < vexp)
+ return -usign;
+
+ usize = ABS (usize);
+ vsize = ABS (vsize);
+
+ up = PTR (u);
+ vp = PTR (v);
+
+#define STRICT_MPF_NORMALIZATION 0
+#if ! STRICT_MPF_NORMALIZATION
+ /* Ignore zeroes at the low end of U and V. */
+ do {
+ mp_limb_t tl;
+ tl = up[0];
+ MPN_STRIP_LOW_ZEROS_NOT_ZERO (up, usize, tl);
+ tl = vp[0];
+ MPN_STRIP_LOW_ZEROS_NOT_ZERO (vp, vsize, tl);
+ } while (0);
+#endif
+
+ if (usize > vsize)
+ {
+ cmp = mpn_cmp (up + usize - vsize, vp, vsize);
+ /* if (cmp == 0) */
+ /* return usign; */
+ ++cmp;
+ }
+ else if (vsize > usize)
+ {
+ cmp = mpn_cmp (up, vp + vsize - usize, usize);
+ /* if (cmp == 0) */
+ /* return -usign; */
+ }
+ else
+ {
+ cmp = mpn_cmp (up, vp, usize);
+ if (cmp == 0)
+ return 0;
+ }
+ return cmp > 0 ? usign : -usign;
+}