cnd_mpn_zero (int cnd, volatile mp_ptr rp, mp_size_t n)
{
  volatile mp_limb_t c;
  volatile mp_limb_t mask = (mp_limb_t) cnd - 1;

  while (--n >= 0)
    {
      c = rp[n];
      c &= mask;
      rp[n] = c;
    }
}
cnd_mpn_zero (int cnd, volatile mp_ptr rp, mp_size_t n)
{
  volatile mp_limb_t c;
  volatile mp_limb_t mask = (mp_limb_t) cnd - 1;

  while (--n >= 0)
    {
      c = rp[n];
      c &= mask;
      rp[n] = c;
    }
}