From:	Mark Slagell <bald_soprano AT geocities DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	setting segment register for string instructions
Date:	Mon, 26 May 1997 04:53:28 -0500
Organization:	dept. of redundancy dept.
Lines:	12
Message-ID:	<33895D98.1322@geocities.com>
NNTP-Posting-Host:	dial20.ppp.iastate.edu
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

I couldn't find an answer for this in the FAQ....

Using string instructions, I'm getting me some intermittent crashes. 
I'm guessing my problem is that I need to set %ds explicitly, but to
what?  The memory being addressed is an ordinary C array, so I'm not
trying to access conventional DOS memory or anything like that.

I've noticed the compiler never seems to generate string instructions. 
Maybe the speed difference between "movw (%ebx),%ax; addl $2,%ebx" and
"lodsw" is insignificant anyway, but I'd still like to figure this out.

  -- Mark

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