Carry out basic expression simplification. (UNSOUND)
This transform does a lot of basic rewriting of expressions, e.g., it will eliminate double negations, propagate constants through ANDs, use Demorgan's rule to simplify negated ANDs, pushing nots down into the branches of ?: expressions, and so forth.
WARNING: These transforms are almost certainly unsound in general.
For instance, even something as simple as removing double negatives isn't
stricly correct,
BUT FOR SERIOUSLY -- WARNING: I am really not too concerned with soundness here. There are probably many things that could go wrong w.r.t. expression sizes, etc. You should check that this produces reasonable output using an equivalence checker.