https://bugs.winehq.org/show_bug.cgi?id=23816
--- Comment #32 from Esme Povirk madewokherd@gmail.com --- Examining the code, it seems to be failing on a function with more static branches than actual instructions. ILSpy is in agreement with Mono that the code is invalid.
While I don't think it's possible to make Mono's JIT accept this code, it's probably feasible to preprocess the code into something valid. I've also seen other programs that could benefit from this.
But, this is a big project, and I'm still working on getting WPF working more than 5% of the time, so it'll have to wait.