pqc/external/flint-2.4.3/fq_poly_templates/divrem_basecase.c
2014-05-24 23:16:06 +02:00

128 lines
3.7 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) 2012 Sebastian Pancratz
Copyright (C) 2013 Mike Hansen
******************************************************************************/
#ifdef T
#include "templates.h"
void
_TEMPLATE(T, poly_divrem_basecase) (TEMPLATE(T, struct) * Q,
TEMPLATE(T, struct) * R,
const TEMPLATE(T, struct) * A, slong lenA,
const TEMPLATE(T, struct) * B, slong lenB,
const TEMPLATE(T, t) invB,
const TEMPLATE(T, ctx_t) ctx)
{
slong iQ, iR;
if (R != A)
_TEMPLATE(T, poly_set) (R, A, lenA, ctx);
for (iQ = lenA - lenB, iR = lenA - 1; iQ >= 0; iQ--, iR--)
{
if (TEMPLATE(T, is_zero) (R + iR, ctx))
TEMPLATE(T, zero) (Q + iQ, ctx);
else
{
TEMPLATE(T, mul) (Q + iQ, R + iR, invB, ctx);
_TEMPLATE(T, TEMPLATE(poly_scalar_submul, T)) (R + iQ, B, lenB,
Q + iQ, ctx);
}
}
}
void
TEMPLATE(T, poly_divrem_basecase) (TEMPLATE(T, poly_t) Q,
TEMPLATE(T, poly_t) R,
const TEMPLATE(T, poly_t) A,
const TEMPLATE(T, poly_t) B,
const TEMPLATE(T, ctx_t) ctx)
{
const slong lenA = A->length, lenB = B->length, lenQ = lenA - lenB + 1;
TEMPLATE(T, struct) * q, *r;
TEMPLATE(T, t) invB;
if (lenA < lenB)
{
TEMPLATE(T, poly_set) (R, A, ctx);
TEMPLATE(T, poly_zero) (Q, ctx);
return;
}
TEMPLATE(T, init) (invB, ctx);
TEMPLATE(T, inv) (invB, TEMPLATE(T, poly_lead) (B, ctx), ctx);
if (Q == A || Q == B)
{
q = _TEMPLATE(T, vec_init) (lenQ, ctx);
}
else
{
TEMPLATE(T, poly_fit_length) (Q, lenQ, ctx);
q = Q->coeffs;
}
if (R == B)
{
r = _TEMPLATE(T, vec_init) (lenA, ctx);
}
else
{
TEMPLATE(T, poly_fit_length) (R, lenA, ctx);
r = R->coeffs;
}
_TEMPLATE(T, poly_divrem_basecase) (q, r, A->coeffs, lenA,
B->coeffs, lenB, invB, ctx);
if (Q == A || Q == B)
{
_TEMPLATE(T, vec_clear) (Q->coeffs, Q->alloc, ctx);
Q->coeffs = q;
Q->alloc = lenQ;
Q->length = lenQ;
}
else
{
_TEMPLATE(T, poly_set_length) (Q, lenQ, ctx);
}
if (R == B)
{
_TEMPLATE(T, vec_clear) (R->coeffs, R->alloc, ctx);
R->coeffs = r;
R->alloc = lenA;
R->length = lenA;
}
_TEMPLATE(T, poly_set_length) (R, lenB - 1, ctx);
_TEMPLATE(T, poly_normalise) (R, ctx);
TEMPLATE(T, clear) (invB, ctx);
}
#endif