Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!bloom-beacon!apple!baum
From: baum@Apple.COM (Allen J. Baum)
Newsgroups: comp.arch
Subject: Re: Assembly or ....
Message-ID: <21692@apple.Apple.COM>
Date: 5 Dec 88 19:03:41 GMT
References: <1388@aucs.UUCP| <729@convex.UUCP> <1961@crete.cs.glasgow.ac.uk> <7740@boring.cwi.nl> <1039@l.cc.purdue.edu> <79744@sun.uucp> <1842@scolex>
Reply-To: baum@apple.UUCP (Allen Baum)
Organization: Apple Computer, Inc.
Lines: 23

[]
>In article <1842@scolex> seanf@sco.COM (Sean Fagan) writes:
>In article <1039@l.cc.purdue.edu> cik@l.cc.purdue.edu (Herman Rubin) writes:
>>
>>Can division be pipelined?  In scalar mode on the CYBER 205, division is not
>>subject for pipelining.  I believe that this is the case because too much of
>>the dividend must be retained throughout.

Division can be pipelined, allthough I suspect that the reason it isn't is
that you may as well just duplicate the divider (I'm talking integer division
here).

There is at least one example of a systolic array integer divider:
see "Integer Division in Linear Time with Bounded Fan-in by C. Purdy
and G. Purdy, IEEE Trans. on Computers, V. C-36#5, May 1987, pp640-644.

Finally, there were some claims of a Newton iteration divide step
operation on the RPM-40. Those folks are still on the net, but I
guess decided they weren't allowed to talk about it, so no details emerged.

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