byuu says:

This probably won't fix the use of register yet (I imagine ruby and hiro
will complain now), but ... oh well, it's a start. We'll get it
compiling again eventually.

I added JP, JR, JRL, LD instructions this time around. I'm also starting
to feel that Byte, Word, Long labels for the TLCS900H aren't really
working. There's cases of needing uint24, int8, int16, ... it may just
be better to name the types instead of trying to be fancy.

At this point, all of the easy instructions are in. Now it's down to a
whole lot of very awkward bit-manipulation and special-use instructions.
Sigh.