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From: ewhac@well.UUCP
Newsgroups: comp.sys.amiga
Subject: Re: 68k word-alignment penalty?
Message-ID: <2837@well.UUCP>
Date: Fri, 27-Mar-87 17:44:05 EST
Article-I.D.: well.2837
Posted: Fri Mar 27 17:44:05 1987
Date-Received: Sat, 28-Mar-87 16:24:21 EST
References: <8703242118.AA05186@cory.Berkeley.EDU>
Reply-To: ewhac@well.UUCP (Leo 'Bols Ewhac' Schwab)
Organization: Whole Earth 'Lectronic Link, Sausalito, CA
Lines: 45
Summary: It was a joke!

In article <8703242118.AA05186@cory.Berkeley.EDU> dillon@CORY.BERKELEY.EDU (Matt Dillon) writes:
>>	Some system software designers, in their shorsightedness, fail to
>>provide even this basic exception handler in the OS.  Thus, the execution
>>time for an odd-address word fetch on such a system increases by several
>>orders of magnitude; from tens of seconds to almost forever.  Some
>>particularly snobbish OS designers are presumptuous enough to assume that
>>such code is in error, and design the exception handler to stop your program
>>dead in its tracks.  As anyone can see, this is clearly The Wrong Thing.
>
>	Excuse me, did I hear you say 'basic'?  This 'basic' exception handler
>of yours would have to fully decode the instruction in question (assuming 
>68000), skip the part before the exception occured, and manually simulate the
>remainder.  And your saying "designers, in their shortsightedness"?
>
>	Get A Life!   Nobody in their right mind does an odd-address word
>fetch on a 68000 on purpose!
>
>					-Matt

	Woah!  Hey, wait a minute!  Did no one notice the first line in the
posting which read:

[ Please set your local SIMLEY_FACE bit when reading this article. ]

	It was a satire!  I know that no one does odd address word fetch on
purpose.  I thought the article was outrageous enough that no one would
possibly take it seriously.  Guess I'll have to improve my satire skills.

	He asked if there was a performance penalty for doing odd word
access, and I said Yes.  The program crashes.  That strikes me as a
performance degradation, how about you?

	Maybe I should have put SATIRE_ON at the top of the article...

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