Modafinil helps. What I do whenever I get stuck on a bad sleep schedule is stay up all night, take 100mg around 5am and it keeps me up through the rest of the day more or less. By evening I would have been up for over 24 hours, plus the come down from the pill is pretty rough. So both staying awake that long and the drugs wearing off leaves me exhausted, and I end up going to sleep.
You'll wake up early the next morning, like 2am. Do it again, this time without the pill. Again you'll be tired by early evening and sleep early and wake up early. On the third day take another 100mg, this time it should keep you up until night time, and then you can reset your sleep schedule back to a good one from the fourth day onwards.