Message-Id:	<m10BKiA-000S6EC@inti.gov.ar>
Comments:	Authenticated sender is <salvador AT natacha DOT inti DOT gov DOT ar>
From:	"Salvador Eduardo Tropea (SET)" <salvador AT inti DOT gov DOT ar>
Organization:	INTI
To:	Paul Derbyshire <pderbysh AT usa DOT net>, djgpp AT delorie DOT com
Date:	Fri, 12 Feb 1999 12:44:04 +0000
MIME-Version:	1.0
Subject:	Re: Asm question
In-reply-to:	<3.0.6.32.19990212092623.00840750@pop.netaddress.com>
X-mailer:	Pegasus Mail for Windows (v2.54)
Reply-To:	djgpp AT delorie DOT com

Paul Derbyshire <pderbysh AT usa DOT net> wrote:

> I notice gcc zeroes eax using
> 
> 
> xorl  %eax, %eax
> 
> rather than
> 
> movl  $0, %eax
> 
> Is the xorl faster or more pipelinable or something? Seems
> counterintuitive. :-)

Needs less bytes, movl needs the 32 bits for the 0 plus the opcode.

SET 
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