Re: Semaphore assembly-code bug

[Jeff Garzik]

Linus Torvalds wrote:
> Anyway, it's quite likely that for several CPU's the fastest sequence ends 
> up actually being 
>
> 	movl 4(%esp),%ecx
> 	movl 8(%esp),%edx
> 	movl 12(%esp),%eax
> 	addl $16,%esp
>
> which is also one of the biggest alternatives.


That's how I'm coding the sparse "compiler backend"...  the mov's and 
add's tend to be tiny instructions (i-cache friendly), and you can often 
issue a bunch of them through multiple pipes/ports.

	Jeff


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