diff options
Diffstat (limited to 'vendor/gmp-6.3.0/mpn/generic/cnd_swap.c')
-rw-r--r-- | vendor/gmp-6.3.0/mpn/generic/cnd_swap.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/vendor/gmp-6.3.0/mpn/generic/cnd_swap.c b/vendor/gmp-6.3.0/mpn/generic/cnd_swap.c new file mode 100644 index 0000000..83d856d --- /dev/null +++ b/vendor/gmp-6.3.0/mpn/generic/cnd_swap.c @@ -0,0 +1,50 @@ +/* mpn_cnd_swap + + Contributed to the GNU project by Niels Möller + +Copyright 2013, 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" + +void +mpn_cnd_swap (mp_limb_t cnd, volatile mp_limb_t *ap, volatile mp_limb_t *bp, + mp_size_t n) +{ + volatile mp_limb_t mask = - (mp_limb_t) (cnd != 0); + mp_size_t i; + for (i = 0; i < n; i++) + { + mp_limb_t a, b, t; + a = ap[i]; + b = bp[i]; + t = (a ^ b) & mask; + ap[i] = a ^ t; + bp[i] = b ^ t; + } +} |