Machine-generated schedules are sensitive to Func names

[abadams]

They're indexed by number in a topological sort. In the case of ties, the Func name has an influence on the order of the sort. This means that if you compile a generator with debugging symbols and automagical Func names kick in, you may invalidate a generated schedule.

In general though it would be nice to be able to change superficial things like Func names without breaking the schedule. We need to figure out a more stable ordering.

[steven-johnson]

...hash the overall IRNode tree of a Func?