This only applies to people who have accumulated presence after April 1, 1997.
This is only applies for unauthorized time during a single stay. So if you stayed for 179 days beyond the time allowed you, left, and then returned and stayed an additional 179 days past the allowed time, you are not subject to the three year bar.
Here are some examples where unlawful presence does not accrue: o Granted voluntary departure;
o Granted Temporary Protected Status;
o You have pending adjustment application;
o Granted withholding of removal;
o Granted a Stay of Removal;
o Granted Deferred Action; and
o Granted Cancellation of Removal