IEEE_SW_MASK
w = current_thread_info()->ieee_state & IEEE_SW_MASK;
*state = (*state & ~IEEE_SW_MASK) | (swcr & IEEE_SW_MASK);
swcr = (*state & IEEE_SW_MASK) | exc;
= task_thread_info(task)->ieee_state & IEEE_SW_MASK;
= ((task_thread_info(task)->ieee_state & ~IEEE_SW_MASK)
| (data & IEEE_SW_MASK));