yes. Calton Pu. is that really such a problem? JITs seem to work pretty well, I'm pretty sure synthesis was more about creating custom paths than being strictly self-modifying, but it's been a long time.

update: oh, I just remembered why it _is_ an issue for modern processors, Massalin leaned very heavily on the general purpose double compare-and-swap that was present on some generations of the 68k architecture, and x86-64 only has double contiguous compare and swap