From:	Fabrice ILPONSE <fabrice AT asim DOT lip6 DOT fr>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: assembly language
Date:	Wed, 26 Aug 1998 10:24:36 +0200
Organization:	Universites Paris VI/Paris VII - France
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References:	<01J10IURTRN694HU4A AT SLU DOT EDU>
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To:	djgpp AT delorie DOT com
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GAMMELJL AT SLU DOT EDU wrote:
> 
>      Thanks to those who responded to my query about
>         movl $0x0,%edx    vs    xorl %edx,%edx
> The movl sets %edx to zero, whereas xorl sets %edx and the carry bit to
> zero.  Thus the two statements above are not exactly the same thing.
> This fact could make little difference to all but a few programmers,
> and those few probably already know to avoid the xorl command when
> writing codes in assembly language.  I find that the movl command
> results in faster executables even when xorl can be used as above
> (in those cases in which the carry bit does not matter).

Hi!!
	the problem with the movl is that the instruction code is bigger
because of the constate $0x0 that is included in it whereas not for the
xorl... ;)

bye
-- 
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	+-+-+	Fabrice ILPONSE
	  |	email: fabrice AT asim DOT lip6 DOT fr
	  |
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