Reduce reliance on main "canonicalize" pattern


I think the correct thing here is to do the following:

- where we rely on specific canonicalization patterns as an integral part of the pass pipeline, put those patterns in a specific name passed, so that if they ever get removed/etc upstream, we don't get sudden failures without warning)
- Verify that all pipelines still produce code succesfully if the canonicalization is removed/replaced with no-op
- how to efficiently set all canonicalize passes to no-op? (Maybe overwrite the definition of addCanonicalizerPass to be no-op?)
- how to efficiently check that the output is still "correct" even though it's now syntactically different (i.e., FileCheck tests will fail?)