pqc/external/flint-2.4.3/fq_zech/add.c

53 lines
1.6 KiB
C

/*=============================================================================
This file is part of FLINT.
FLINT is free software; you can redistribute it and/or modify
it under the terms of 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.
FLINT 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 a copy of the GNU General Public License
along with FLINT; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2013 Mike Hansen
******************************************************************************/
#include "fq_zech.h"
void
fq_zech_add(fq_zech_t rop, const fq_zech_t op1, const fq_zech_t op2,
const fq_zech_ctx_t ctx)
{
mp_limb_t index, c;
if (op1->value == ctx->qm1)
{
rop->value = op2->value;
}
else if (op2->value == ctx->qm1)
{
rop->value = op1->value;
}
else
{
index = n_submod(op1->value, op2->value, ctx->qm1);
c = ctx->zech_log_table[index];
if (c != ctx->qm1)
{
c = n_addmod(c, op2->value, ctx->qm1);
}
rop->value = c;
}
}