40ec50d0b6
When relaxing a branch, restrict the set of candidate encodings to those which have the same input constraints as the original encoding choice. This prevents situations where relaxation prefers a non-REX-prefixed encoding over a REX prefixed one because the end of the instruction can be one byte closer to the destination, in a situation where the encoding needs to be REX-prefixed because of one of the operand registers. This also makes the Context class perform encoding verification after relaxation, to catch similar problems in the future. Fixes #256.
This crate contains the core Cretonne code generator. It translates code from an intermediate language into executable machine code.