a4c1147045
As explained in the added documentation and #1342, if we prevent `infer_rex()` and `w()` from being used together then we don't need to check whether the W bit is set when figuring out if a REX prefix is needed in `needs_rex()`. This should improve compile time for x86 very slightly since all `infer_rex()` instructions will no longer need this check.
This crate contains the core Cranelift code generator. It translates code from an intermediate representation into executable machine code.