4 Jul
2015
4 Jul
'15
1:04 p.m.
On 07/04/2015 11:16 AM, Diane Bruce wrote:
Sure, and the information they did push on the stack when they finally
added instruction continuation was pretty hefty. 68010 had that with
limited addressing (Which the MAC (ab)used).
I recall that I'd suggested to the guy at WESCON that a programmable
trap for user-mode instructions would be most valuable. The
instructions that raised Cain with virtual memory implementations could
be implemented with other, simpler, instructions--if only they could be
trapped before issue--and emulated by a bit of supervisor code.
He admitted that it was a good idea, but that the 68010 design was
already being tested, so it was unlikely to see my idea done.
Of course, today, with very few people programming in much at a lower
level than "C", the obvious solution would be never to generate the
problem instructions.
--Chuck