Path: utzoo!attcan!uunet!husc6!mailrus!ames!amdahl!mat
From: mat@amdahl.uts.amdahl.com (Mike Taylor)
Newsgroups: comp.arch
Subject: Re: Superoptimiser.
Message-ID: <92QGLe0P1P1010Tz5Qs@amdahl.uts.amdahl.com>
Date: 2 Jul 88 03:22:12 GMT
References: <28200172@urbsdc> <13157@apple.Apple.COM>
Organization: Amdahl Corporation, Sunnyvale CA
Lines: 14

> 
> I don't believe that any model of IBM 360 or 370 (including /91, /92, or /195)
> ever executed multiple threads and threw away the unused one.

As I recall, the 3033 did this ( and I think maybe the 168 too, but I'm not
sure about that), in a limited sense.  The 3033 was the "tiger team" response
to Amdahl's 470 V/6. It had a three(two?)-pipe IPPF (Instruction Pre-Processing
Facility) that got three(two?) instruction streams ready for processing - i.e.
operands checked and ready to go, etc. However, I don't think any machine has
had multiple E-units, as you point out.
-- 
Mike Taylor                               ...!{hplabs,amdcad,sun}!amdahl!mat

[ This may not reflect my opinion, let alone anyone else's.  ]