Yep, and notwithstanding split I/D, we switched to -n (410 magic) read-only code space.
Agreed, that was pretty standard and used the sticky bit as needed. IIRC this was to help sharing, but I admit those bits in my brain had not been refreshed in years.
Of course, the kludge nargs() function didn’t work at all in split-I/D mode unless you made a hack to the processor to change the behavior of MFPI.
Ah yes, I've forgotten that hack. Does simh or any of the other simulators support it? It would need to be an option of course.