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Mail Archives: djgpp/1997/10/18/02:18:35

From: tom burgess <tburgess AT drao DOT nrc DOT ca>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: [Q] Which is faster?
Date: Fri, 17 Oct 1997 19:51:18 -0700
Organization: BCTEL Advanced Communications
Lines: 14
Message-ID: <34482426.74D1@drao.nrc.ca>
References: <628kkv$16c AT usenet DOT kreonet DOT re DOT kr>
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

good AT soback DOT kornet DOT nm DOT kr wrote:
> 
> I have a question in DJGPP inline assembly.
> Among MOVW %AX, %BX, MOVL %EAX, %EBX
> 
> This is just about speed, not others.
> 
> Thanks in advance.

On 386 and 486, same speed. On Pentium, 16 bit operations (MOVW) are
SLOWER. (1 cycle prefix byte penalty, plus additional penalties
because instruction pairing is disabled)

	regards, tom

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