From:	Tom Burgess <Tom_Burgess AT bc DOT sympatico DOT ca>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: What is faster STOSD or MOVSD
Date:	Mon, 14 Apr 1997 21:51:32 -0700
Organization:	BCTEL Advanced Communications
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Message-ID:	<33530954.4366@bc.sympatico.ca>
References:	<5iu501$rqj AT nr1 DOT toronto DOT istar DOT net>
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To:	djgpp AT delorie DOT com
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Jeff Weeks wrote:
> 
> Which is faster?
> 
> rep stosd or
> rep movsd
>               486 cycles    Pentium
rep movs:     11+(3.3)n     13+(1.1)n
rep stos:     8+(4.1)n      5+(4.5)n

rep movs wins (for aligned transfers within primary cache). Recommended
book for good info on optimization issues: "Inner Loops" by Rick Booth.

	regards, tom

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