Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!ico!rcd
From: rcd@ico.isc.com (Dick Dunn)
Newsgroups: comp.arch
Subject: 64/32 bit processors - impending disaster?
Message-ID: <1990Feb12.182411.5982@ico.isc.com>
Date: 12 Feb 90 18:24:11 GMT
Organization: Interactive Systems Corporation, Boulder, CO
Lines: 19

I've changed my mind a few times on this, but I think we're likely to see
64-bit addresses (or, at the least, larger-than-32-bit addresses) a while
before we see 64-bit integers.  Reasoning:  I see more machines pushing
toward a gigabyte of storage, and if you're putting that much physical
memory on a machine, surely you can create processes with virtual>real.
But 64-bit integer operations, particularly multiply/divide, are still sort
of expensive...too expensive to justify the limited return.  32 bits is a
big number.

If this 64/32 split happens, it's not going to be a happy situation, as
anyone who's ever fought a 286 in large muddle will realize.  Having a
pointer larger than an integer breaks LOTS of C code.  To be sure, the code
usually breaks because it's poorly written, but it may still be heavily
used.  Any program that doesn't get lint-ed regularly is likely to be
broken, especially if it uses linked structures.  Yacc grammars are a
complete disaster.
-- 
Dick Dunn     rcd@ico.isc.com    uucp: {ncar,nbires}!ico!rcd     (303)449-2870
   ...Mr. Natural says, "Use the right tool for the job."