If you propagate "some condition," that could allow dead-code elimination later on, especially if an if-statement uses "some condition" as a predicate later. This seems redundant in hand-written code, but keep in mind the if-statement may actually be from an inlined function.
If "some condition" is actually testing a variable for equality, then you could do constant-folding.
If "some condition" is actually testing a variable for equality, then you could do constant-folding.