Style

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Added treesort benchmark in the jit test setup

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Added execute_void, invoke_void

This cuts off execution of side-effect-free code early.
Hope this will make life for the optimizer easier.

Signed-off-by: Stefan Marr <git@stefan-marr.de>