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From: jsa@alexandria (Jon S Anthony)
Subject: Re: CRC in Ada?
Date: 1997/03/06
Message-ID: <JSA.97Mar6131131@alexandria>#1/1
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Distribution: world
References: <1997Mar2.220652@nova.wright.edu>
Organization: PSI Public Usenet Link
Newsgroups: comp.lang.ada
Date: 1997-03-06T00:00:00+00:00
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In article <dewar.857612984@merv> dewar@merv.cs.nyu.edu (Robert Dewar) writes:

> Jon Anthony asks
> 
> <<That sounds very odd.  Did you use very different implementation
> styles?  For example, maybe use unconstrained types in the Ada or some
> such?  In general I would think a similar implementation style here
> would yield basically the same "efficiency" result.>>
> 
> One possibility is that the implementation was relying on doing rotates,
> and there certainly is no easy portable efficient way of doing that
> in Ada 83 (although for my taste I prefer to use table lookup for
> computing CRC's and avoid the bit rotation stuff.

Right.  That's a good example of the sort of thing I was fishing for,
but I guess it really had to do with the IO involved...

/Jon
-- 
Jon Anthony
Organon Motives, Inc.
Belmont, MA 02178
617.484.3383
jsa@organon.com