sync_test_bit
evtchn_pending = sync_test_bit(port, BM(&s->evtchn_pending[0]));
if (sync_test_bit(i, BM(sh->evtchn_pending))) {
sync_test_bit(word_idx, BM(&v->evtchn_pending_sel))
!sync_test_bit(i, BM(sh->evtchn_mask))
sync_test_bit(i, BM(cpu_evtchn))
return sync_test_bit(port, BM(&s->evtchn_pending[0]));
return sync_test_bit(EVTCHN_FIFO_BIT(PENDING, word), BM(word));
return sync_test_bit(EVTCHN_FIFO_BIT(MASKED, word), BM(word));