freebsd-dev/contrib/libgmp/mpz/mul_ui.c

65 lines
1.8 KiB
C
Raw Normal View History

/* mpz_mul_ui(product, multiplier, small_multiplicand) -- Set
PRODUCT to MULTIPLICATOR times SMALL_MULTIPLICAND.
Copyright (C) 1991, 1993, 1994, 1996 Free Software Foundation, Inc.
This file is part of the GNU MP Library.
The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
The GNU MP Library 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 Library General Public
License for more details.
You should have received a copy of the GNU Library General Public License
along with the GNU MP Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include "gmp.h"
#include "gmp-impl.h"
void
#if __STDC__
mpz_mul_ui (mpz_ptr prod, mpz_srcptr mult, unsigned long int small_mult)
#else
mpz_mul_ui (prod, mult, small_mult)
mpz_ptr prod;
mpz_srcptr mult;
unsigned long int small_mult;
#endif
{
mp_size_t size = mult->_mp_size;
mp_size_t sign_product = size;
mp_limb_t cy;
mp_size_t prod_size;
mp_ptr prod_ptr;
size = ABS (size);
if (size == 0 || small_mult == 0)
{
prod->_mp_size = 0;
return;
}
prod_size = size + 1;
if (prod->_mp_alloc < prod_size)
_mpz_realloc (prod, prod_size);
prod_ptr = prod->_mp_d;
cy = mpn_mul_1 (prod_ptr, mult->_mp_d, size, (mp_limb_t) small_mult);
if (cy != 0)
{
prod_ptr[size] = cy;
size++;
}
prod->_mp_size = sign_product >= 0 ? size : -size;
}