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

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/* mpf_mul_ui -- Multiply a float and an unsigned integer.
Copyright (C) 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__
mpf_mul_ui (mpf_ptr r, mpf_srcptr u, unsigned long int v)
#else
mpf_mul_ui (r, u, v)
mpf_ptr r;
mpf_srcptr u;
unsigned long int v;
#endif
{
mp_srcptr up;
mp_size_t usize;
mp_size_t size;
mp_size_t prec = r->_mp_prec;
mp_limb_t cy_limb;
mp_ptr rp;
usize = u->_mp_size;
size = ABS (usize);
rp = r->_mp_d;
up = u->_mp_d;
if (size > prec)
{
up += size - prec;
size = prec;
}
#if 0
/* Since we can do it at almost no cost, remove zero limbs at low end of
result. */
if (up[0] == 0)
up++, size--;
#endif
if (size == 0 || v == 0)
{
r->_mp_size = 0;
r->_mp_exp = 0; /* ??? */
}
else
{
cy_limb = mpn_mul_1 (rp, up, size, (mp_limb_t) v);
rp[size] = cy_limb;
cy_limb = cy_limb != 0;
r->_mp_exp = u->_mp_exp + cy_limb;
size += cy_limb;
r->_mp_size = usize >= 0 ? size : -size;
}
}