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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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