As someone who has implemented full match in several industrial languages: this isn’t really match; it doesn’t not handle unpacking. And that is by far the only interesting bit. This feature is more accurately called `cond` à la Scheme, and you can fully expand it away ahead of type checking. Looking at unpacking in the arms, even with Scheme’s truth-y values and `=>`, could be neat.

Optimizing well-known jumps is useful, as is branch reordering, but the tombstone flag is unnecessary; you can simply write down a list of all targeted / called blocks and perform dead block elimination more generally that way.