CR8 is not special in any way as far as the assembler is concerned.
CR8 is not special in any way as far as the assembler is concerned. It's
listed as having a special form in the Intel documentation, but that is
only because there are no other CRs which require a REX prefix.
MOV to CR8 is special in the sense that it's a non-serializing
instruction, but that's irrelevant to the assembler.
Furthermore, it's totally unclear how TRs should be handled in long mode;
there are no CPUs which uses TRs which also have long mode, so the easiest
is to simply mark those instructions NOLONG.
Finally, add PRIV to some privileged instructions.