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From: sundar@cwruecmp.UUCP (Sundar R. Iyengar)
Newsgroups: net.lang.c,net.lang.c++,net.arch
Subject: iAPX 432
Message-ID: <1474@cwruecmp.UUCP>
Date: Tue, 6-May-86 09:50:37 EDT
Article-I.D.: cwruecmp.1474
Posted: Tue May  6 09:50:37 1986
Date-Received: Wed, 7-May-86 06:12:53 EDT
Reply-To: sundar@cwruecmp.UUCP (Sundar R. Iyengar)
Organization: CWRU Dept. Computer Eng., Cleveland, OH
Lines: 18
Xref: watmath net.lang.c:8883 net.lang.c++:195 net.arch:3210

>> >Now, if only somebody would invent an architecture where all objects,
>> >including dynamicly allocated objects, are isolated in memory, then any
>> >subscript error would cause an immediate memory fault.
>>
>>    If I'm not mistaken, this was done on the iAPX432, using a capability-
>> based addressing scheme.  Dimmed the lights.  You could probably construct
>> such an environment on the 80286, but no one does, probably for efficiency
>> reasons.

> One problem with the 432's approach was that it was very extreme; I don't
> think it's good to say "the 432 tried these approaches and it was too slow,
> therefore the checking can't be efficiently implemented."

If I remember correctly, iAPX 432 is a vertically microcoded machine.
On top of that, the microcode is generated in one chip and then used in
another.  These two are some more reasons why iAPX is slow.

-- sri