Re: The Kommunity vs. Dick Johnson

Pete Chown (Pete.Chown@skygate.co.uk)
Tue, 17 Nov 1998 10:29:24 +0000


The other problem in this area is that the rules for instruction
sequencing are different on each processor revision, and can make up to
a factor of two difference. Also the "CISC" instructions tend to be
disproportionately slow on 486s but not on the others as far as I know.
This means that you can write assembly code which runs well on one
processor but not another. By contrast, gcc can be told which processor
to optimise for so hopefully it should give more consistent performance.

(I am not taking one side or the other here. I think it is evident that
hand coded assembly language should be faster if done carefully by
someone with a sound knowledge of the processor. On the other hand,
taking full advantage of a modern processor is extremely difficult.)

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fax +44 (0) 181 680 8474, mobile +44 (0) 468 765 645,
post 58 Foss Avenue, Croydon, CR0 4EU, England

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