Will write better documentation later, mostly uploaded for reference now. Get the source here.
It interfaces with three half-bridge drivers with inverting inputs (it was written to drive the Prius IPM, which behaves as such). No throttle support yet (I was more interested in getting sinusoidal PWM working) but that should be real easy to add.
Connect your phases to digital pins 5, 6, and 11 and your Hall sensors to pins A0, A1, and A2.