0af8737ec3
With these fixes, all this PR has to do is instantiate and run the checker on the `regalloc2::Output`. This is off by default, and is enabled by setting the `regalloc_checker` Cranelift option. This restores the old functionality provided by e.g. the `backtracking_checked` regalloc algorithm setting rather than `backtracking` when we were still on regalloc.rs.
This crate contains the core Cranelift code generator. It translates code from an intermediate representation into executable machine code.