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Re: CVS commit: syssrc/sys/lib/libkern/arch/i386



On 21 Sep 2001 17:14:31 +0300, Frank van der Linden wrote:
> 
> Module Name:  syssrc
> Committed By: fvdl
> Date:         Fri Sep 21 14:14:30 UTC 2001
> 
> Modified Files:
>       syssrc/sys/lib/libkern/arch/i386: memcmp.S
> 
> Log Message:
> Make new gas happy. Use movzbl instead of xorl + movb.

This sort of thing may seem obvious, but remember that movzbl incurs an
extra penalty on the 386 and 486.  It's usually preferrable to zero the
target register outside the loop and use movb.




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