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diff --git a/Build/source/libs/gmp/gmp-6.0.0/mpn/generic/cnd_sub_n.c b/Build/source/libs/gmp/gmp-6.0.0/mpn/generic/cnd_sub_n.c
new file mode 100644
index 00000000000..bd8e029a36f
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+++ b/Build/source/libs/gmp/gmp-6.0.0/mpn/generic/cnd_sub_n.c
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+/* mpn_cnd_sub_n -- Compute R = U - V if CND != 0 or R = U if CND == 0.
+ Both cases should take the same time and perform the exact same memory
+ accesses, since this function is intended to be used where side-channel
+ attack resilience is relevant.
+
+Copyright 1992-1994, 1996, 2000, 2002, 2008, 2009, 2011, 2013 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.h"
+#include "gmp-impl.h"
+
+mp_limb_t
+mpn_cnd_sub_n (mp_limb_t cnd, mp_ptr rp, mp_srcptr up, mp_srcptr vp, mp_size_t n)
+{
+ mp_limb_t ul, vl, sl, rl, cy, cy1, cy2, mask;
+
+ ASSERT (n >= 1);
+ ASSERT (MPN_SAME_OR_SEPARATE_P (rp, up, n));
+ ASSERT (MPN_SAME_OR_SEPARATE_P (rp, vp, n));
+
+ mask = -(mp_limb_t) (cnd != 0);
+ cy = 0;
+ do
+ {
+ ul = *up++;
+ vl = *vp++ & mask;
+#if GMP_NAIL_BITS == 0
+ sl = ul - vl;
+ cy1 = sl > ul;
+ rl = sl - cy;
+ cy2 = rl > sl;
+ cy = cy1 | cy2;
+ *rp++ = rl;
+#else
+ rl = ul - vl;
+ rl -= cy;
+ cy = rl >> (GMP_LIMB_BITS - 1);
+ *rp++ = rl & GMP_NUMB_MASK;
+#endif
+ }
+ while (--n != 0);
+
+ return cy;
+}