pqc/external/flint-2.4.3/fq_poly_templates/div_basecase.c

126 lines
3.6 KiB
C
Raw Normal View History

2014-05-18 22:03:37 +00:00
/*=============================================================================
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) 2011, 2010 Sebastian Pancratz
Copyright (C) 2008, 2009 William Hart
Copyright (C) 2013 Mike Hansen
******************************************************************************/
#ifdef T
#include "templates.h"
void
_TEMPLATE(T, poly_div_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)
{
const slong alloc = (R == NULL) ? lenA : 0;
slong lenR = lenB - 1, iQ;
if (alloc)
R = _TEMPLATE(T, vec_init) (alloc, ctx);
if (R != A)
_TEMPLATE(T, vec_set) (R + lenR, A + lenR, lenA - lenR, ctx);
for (iQ = lenA - lenB; iQ >= 0; iQ--)
{
if (TEMPLATE(T, is_zero) (R + lenA - 1, ctx))
{
TEMPLATE(T, zero) (Q + iQ, ctx);
}
else
{
TEMPLATE(T, mul) (Q + iQ, R + lenA - 1, invB, ctx);
_TEMPLATE(T, TEMPLATE(vec_scalar_submul, T)) (R + lenA - lenR - 1,
B, lenR, Q + iQ,
ctx);
}
if (lenR - 1 >= iQ)
{
B++;
lenR--;
}
lenA--;
}
if (alloc)
_TEMPLATE(T, vec_clear) (R, alloc, ctx);
}
void
TEMPLATE(T, poly_div_basecase) (TEMPLATE(T, poly_t) Q,
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;
TEMPLATE(T, t) invB;
if (lenA < lenB)
{
TEMPLATE(T, poly_zero) (Q, ctx);
return;
}
TEMPLATE(T, init) (invB, ctx);
TEMPLATE(T, inv) (invB, B->coeffs + (lenB - 1), 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;
}
_TEMPLATE(T, poly_div_basecase) (q, NULL, 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);
}
TEMPLATE(T, clear) (invB, ctx);
}
#endif