Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!pt.cs.cmu.edu!MATHOM.GANDALF.CS.CMU.EDU!lindsay
From: lindsay@MATHOM.GANDALF.CS.CMU.EDU (Donald Lindsay)
Newsgroups: comp.arch
Subject: Arithmetic Instructions
Message-ID: <9759@pt.cs.cmu.edu>
Date: 28 Jun 90 20:37:05 GMT
References: <3300@crash.cts.com> <3806@memqa.uucp> <1990Jun26.052624.16953@cs.umn.edu> <811@ehviea.ine.philips.nl>
Organization: Carnegie-Mellon University, CS/RI
Lines: 14

In article <811@ehviea.ine.philips.nl> leo@ehviea.UUCP (Leo de Wit) writes:
>I think whether you can write efficient arithmetic routines has
>little to do with the sophistication of arithmetic instructions.

Recent machines are really excellent.  Occasionally, it is good to
take a break from knocking them, and remember - for example - the
HP2100, which didn't have an integer subtract instruction.

(You did "I-J" by: loading J: complementing it: adding one: then
adding I. Yes, it didn't have a negate instruction, either.)

From this perspective, RISC machines are actually featureful.
-- 
Don		D.C.Lindsay