284 lines
6.9 KiB
C
284 lines
6.9 KiB
C
|
/*=============================================================================
|
||
|
|
|
||
|
|
Copyright (C) 2007, 2008 David Harvey (zn_poly)
|
||
|
|
Copyright (C) 2013 William Hart
|
||
|
|
|
||
|
|
All rights reserved.
|
||
|
|
|
||
|
|
Redistribution and use in source and binary forms, with or without
|
||
|
|
modification, are permitted provided that the following conditions are met:
|
||
|
|
|
||
|
|
* Redistributions of source code must retain the above copyright notice, this
|
||
|
|
list of conditions and the following disclaimer.
|
||
|
|
* Redistributions in binary form must reproduce the above copyright notice,
|
||
|
|
this list of conditions and the following disclaimer in the documentation
|
||
|
|
and/or other materials provided with the distribution.
|
||
|
|
|
||
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
||
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||
|
|
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
|
||
|
|
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||
|
|
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
||
|
|
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
|
||
|
|
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||
|
|
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
||
|
|
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||
|
|
|
||
|
|
=============================================================================*/
|
||
|
|
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <gmp.h>
|
||
|
|
#include "flint.h"
|
||
|
|
#include "nmod_vec.h"
|
||
|
|
#include "nmod_poly.h"
|
||
|
|
|
||
|
|
/*
|
||
|
|
Same as _nmod_poly_KS2_unpack(), but requires b <= FLINT_BITS
|
||
|
|
(i.e. writes one word per coefficient)
|
||
|
|
*/
|
||
|
|
void
|
||
|
|
_nmod_poly_KS2_unpack1(mp_ptr res, mp_srcptr op, slong n, ulong b,
|
||
|
|
ulong k)
|
||
|
|
{
|
||
|
|
/* limb we're currently extracting bits from */
|
||
|
|
mp_limb_t buf = 0;
|
||
|
|
/* number of bits currently in buf; always in [0, FLINT_BITS) */
|
||
|
|
ulong buf_b = 0;
|
||
|
|
|
||
|
|
/* skip over k leading bits */
|
||
|
|
while (k >= FLINT_BITS)
|
||
|
|
{
|
||
|
|
k -= FLINT_BITS;
|
||
|
|
op++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (k)
|
||
|
|
{
|
||
|
|
buf = *op++;
|
||
|
|
buf >>= k;
|
||
|
|
buf_b = FLINT_BITS - k;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (b == FLINT_BITS)
|
||
|
|
{
|
||
|
|
/* various special cases */
|
||
|
|
if (buf_b)
|
||
|
|
{
|
||
|
|
for (; n > 0; n--)
|
||
|
|
{
|
||
|
|
/* we need bits from both sides of a limb boundary */
|
||
|
|
ulong temp = buf;
|
||
|
|
buf = *op++;
|
||
|
|
*res++ = temp + (buf << buf_b);
|
||
|
|
buf >>= (FLINT_BITS - buf_b);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
for (; n > 0; n--)
|
||
|
|
*res++ = *op++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
ulong mask = (UWORD(1) << b) - 1;
|
||
|
|
|
||
|
|
for (; n > 0; n--)
|
||
|
|
{
|
||
|
|
if (b <= buf_b)
|
||
|
|
{
|
||
|
|
/* buf contains all the bits we need */
|
||
|
|
*res++ = buf & mask;
|
||
|
|
buf >>= b;
|
||
|
|
buf_b -= b;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
/* we need bits from both sides of a limb boundary */
|
||
|
|
ulong temp = buf;
|
||
|
|
buf = *op++;
|
||
|
|
*res++ = temp + ((buf << buf_b) & mask);
|
||
|
|
buf >>= (b - buf_b);
|
||
|
|
buf_b = FLINT_BITS - (b - buf_b);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
Same as _nmod_poly_KS2_unpack(), but requires FLINT_BITS < b <= 2 * FLINT_BITS
|
||
|
|
(i.e. writes two words per coefficient)
|
||
|
|
*/
|
||
|
|
void
|
||
|
|
_nmod_poly_KS2_unpack2(mp_ptr res, mp_srcptr op, slong n, ulong b,
|
||
|
|
ulong k)
|
||
|
|
{
|
||
|
|
/* limb we're currently extracting bits from */
|
||
|
|
mp_limb_t buf = 0;
|
||
|
|
/* number of bits currently in buf; always in [0, FLINT_BITS) */
|
||
|
|
ulong buf_b = 0;
|
||
|
|
|
||
|
|
/* skip over k leading bits */
|
||
|
|
while (k >= FLINT_BITS)
|
||
|
|
{
|
||
|
|
k -= FLINT_BITS;
|
||
|
|
op++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (k)
|
||
|
|
{
|
||
|
|
buf = *op++;
|
||
|
|
buf >>= k;
|
||
|
|
buf_b = FLINT_BITS - k;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (b == 2 * FLINT_BITS)
|
||
|
|
{
|
||
|
|
n *= 2;
|
||
|
|
|
||
|
|
/* various special cases */
|
||
|
|
if (buf_b)
|
||
|
|
{
|
||
|
|
for (; n > 0; n--)
|
||
|
|
{
|
||
|
|
/* we need bits from both sides of a limb boundary */
|
||
|
|
ulong temp = buf;
|
||
|
|
buf = *op++;
|
||
|
|
*res++ = temp + (buf << buf_b);
|
||
|
|
buf >>= (FLINT_BITS - buf_b);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
for (; n > 0; n--)
|
||
|
|
*res++ = *op++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
ulong mask;
|
||
|
|
b -= FLINT_BITS;
|
||
|
|
mask = (UWORD(1) << b) - 1;
|
||
|
|
|
||
|
|
for (; n > 0; n--)
|
||
|
|
{
|
||
|
|
/* shunt one whole limb through first */
|
||
|
|
if (buf_b)
|
||
|
|
{
|
||
|
|
ulong temp = buf;
|
||
|
|
buf = *op++;
|
||
|
|
*res++ = temp + (buf << buf_b);
|
||
|
|
buf >>= (FLINT_BITS - buf_b);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
*res++ = *op++;
|
||
|
|
|
||
|
|
/* now handle the fractional limb */
|
||
|
|
if (b <= buf_b)
|
||
|
|
{
|
||
|
|
/* buf contains all the bits we need */
|
||
|
|
*res++ = buf & mask;
|
||
|
|
buf >>= b;
|
||
|
|
buf_b -= b;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
/* we need bits from both sides of a limb boundary */
|
||
|
|
ulong temp = buf;
|
||
|
|
buf = *op++;
|
||
|
|
*res++ = temp + ((buf << buf_b) & mask);
|
||
|
|
buf >>= (b - buf_b);
|
||
|
|
buf_b = FLINT_BITS - (b - buf_b);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
/*
|
||
|
|
Same as _nmod_poly_KS2_unpack(), but requires 2 * FLINT_BITS < b < 3 * FLINT_BITS
|
||
|
|
(i.e. writes three words per coefficient)
|
||
|
|
*/
|
||
|
|
void
|
||
|
|
_nmod_poly_KS2_unpack3(mp_ptr res, mp_srcptr op, slong n, ulong b,
|
||
|
|
ulong k)
|
||
|
|
{
|
||
|
|
/* limb we're currently extracting bits from */
|
||
|
|
mp_limb_t buf = 0;
|
||
|
|
/* number of bits currently in buf; always in [0, FLINT_BITS) */
|
||
|
|
ulong buf_b = 0, mask;
|
||
|
|
|
||
|
|
/* skip over k leading bits */
|
||
|
|
while (k >= FLINT_BITS)
|
||
|
|
{
|
||
|
|
k -= FLINT_BITS;
|
||
|
|
op++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (k)
|
||
|
|
{
|
||
|
|
buf = *op++;
|
||
|
|
buf >>= k;
|
||
|
|
buf_b = FLINT_BITS - k;
|
||
|
|
}
|
||
|
|
|
||
|
|
b -= 2 * FLINT_BITS;
|
||
|
|
mask = (UWORD(1) << b) - 1;
|
||
|
|
|
||
|
|
for (; n > 0; n--)
|
||
|
|
{
|
||
|
|
/* shunt two whole limbs through first */
|
||
|
|
if (buf_b)
|
||
|
|
{
|
||
|
|
ulong temp = buf;
|
||
|
|
buf = *op++;
|
||
|
|
*res++ = temp + (buf << buf_b);
|
||
|
|
buf >>= (FLINT_BITS - buf_b);
|
||
|
|
|
||
|
|
temp = buf;
|
||
|
|
buf = *op++;
|
||
|
|
*res++ = temp + (buf << buf_b);
|
||
|
|
buf >>= (FLINT_BITS - buf_b);
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
*res++ = *op++;
|
||
|
|
*res++ = *op++;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* now handle the fractional limb */
|
||
|
|
if (b <= buf_b)
|
||
|
|
{
|
||
|
|
/* buf contains all the bits we need */
|
||
|
|
*res++ = buf & mask;
|
||
|
|
buf >>= b;
|
||
|
|
buf_b -= b;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
/* we need bits from both sides of a limb boundary */
|
||
|
|
ulong temp = buf;
|
||
|
|
buf = *op++;
|
||
|
|
*res++ = temp + ((buf << buf_b) & mask);
|
||
|
|
buf >>= (b - buf_b);
|
||
|
|
buf_b = FLINT_BITS - (b - buf_b);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
void
|
||
|
|
_nmod_poly_KS2_unpack(mp_ptr res, mp_srcptr op, slong n, ulong b,
|
||
|
|
ulong k)
|
||
|
|
{
|
||
|
|
if (b <= FLINT_BITS)
|
||
|
|
_nmod_poly_KS2_unpack1 (res, op, n, b, k);
|
||
|
|
else if (b <= 2 * FLINT_BITS)
|
||
|
|
_nmod_poly_KS2_unpack2 (res, op, n, b, k);
|
||
|
|
else /* b < 3 * FLINT_BITS */
|
||
|
|
_nmod_poly_KS2_unpack3 (res, op, n, b, k);
|
||
|
|
}
|