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Date:	Fri, 25 Mar 2005 14:46:04 -0800
From:	Ed Martini <martini@c2micro.com>
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To:	Daniel Jacobowitz <dan@debian.org>
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Subject: Re: Observations on LLSC and SMP
References: <4230DB4C.7090103@c2micro.com> <20050314110101.GF7759@linux-mips.org> <423763B9.2000907@c2micro.com> <20050316120647.GB8563@linux-mips.org> <42446555.6090005@c2micro.com> <20050325193759.GA23046@nevyn.them.org>
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Daniel Jacobowitz wrote:

>On Fri, Mar 25, 2005 at 11:24:05AM -0800, Ed Martini wrote:
>  
>
>>1. If the first part of the if were an ifdef instead it would result in 
>>a code size reduction as well as a runtime performance gain.
>>    
>>
>
>You should spend a little time playing with an optimizing compiler. 
>They're capable of working out when a condition will always be false.
>  
>
Yes, but in the case where R10000_LLSC_WAR is true, but cpu_has_llsc 
returns false there are still two wasted tests, and two blocks of code 
that the compiler can't optimize out.