/* Process one block through 16 successive rounds, omitting the swap in the final round.  */
static void process_block_unit(uint32_t *pl, uint32_t *pr, const uint32_t *sk_exp)
/* Process one block through 16 successive rounds, omitting the swap in the final round.  */
static void process_block_unit(uint32_t *pl, uint32_t *pr, const uint32_t *sk_exp)
{
	int i;
	uint32_t l, r;
	l = *pl;
	r = *pr;
	for (i = 0; i < 16; i ++) {
		uint32_t t;
		t = l ^ Fconf(r, sk_exp);
		l = r;
		r = t;
		sk_exp += 6;
	}
	*pl = r;
	*pr = l;
}