60 lines
1.9 KiB
C
60 lines
1.9 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) 2009 William Hart
|
||
|
|
||
|
******************************************************************************/
|
||
|
|
||
|
#include <gmp.h>
|
||
|
#include "flint.h"
|
||
|
#include "ulong_extras.h"
|
||
|
#include "fmpz.h"
|
||
|
|
||
|
void
|
||
|
fmpz_mul_ui(fmpz_t f, const fmpz_t g, ulong x)
|
||
|
{
|
||
|
fmpz c2 = *g;
|
||
|
|
||
|
if (x == 0)
|
||
|
{
|
||
|
fmpz_zero(f);
|
||
|
return;
|
||
|
}
|
||
|
else if (!COEFF_IS_MPZ(c2)) /* c2 is small */
|
||
|
{
|
||
|
mp_limb_t prod[2];
|
||
|
mp_limb_t uc2 = FLINT_ABS(c2);
|
||
|
|
||
|
/* unsigned limb by limb multiply (assembly for most CPU's) */
|
||
|
umul_ppmm(prod[1], prod[0], uc2, x);
|
||
|
if (c2 < WORD(0))
|
||
|
fmpz_neg_uiui(f, prod[1], prod[0]);
|
||
|
else
|
||
|
fmpz_set_uiui(f, prod[1], prod[0]);
|
||
|
}
|
||
|
else /* c2 is large */
|
||
|
{
|
||
|
/* Promote without val as if aliased both are large */
|
||
|
__mpz_struct *mpz_ptr = _fmpz_promote(f);
|
||
|
flint_mpz_mul_ui(mpz_ptr, COEFF_TO_PTR(c2), x);
|
||
|
}
|
||
|
}
|