This generally falls under the purview of optimizations, which are executed after type checking. In most languages type checking has little to do with the runti

This generally falls under the purview of optimizations, which are executed after type checking. In most languages type checking has little to do with the runtime values and everything to do with types. The existence of a bottom type via exceptions and returning is somewhat an exception to this, sure, but that still doesn't involve picking execution branches. I think you can actually have stuff like this make sense in dependent type systems, though.