There were two errors in the arithmetic imm8 instruction. They accept only REGW, and in case the user write a xxxb opcode that variant needs to be rejected as well (it's not automatically rejected by REGW in case the destination is memory).
There were two errors in the arithmetic imm8 instruction. They accept only REGW, and in case the user write a xxxb opcode that variant needs to be rejected as well (it's not automatically rejected by REGW in case the destination is memory).