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X-Bullshit: content-addressed proxy-scale GPU-scale TOR polling realtime-java layer 
Subject: Re: [9front] [PATCH] branchless assembly abs() and labs() for amd64
Reply-To: 9front@9front.org
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> Quoth Kemal <kemalinanc8@gmail.com>:
>> hello,
>> 
>> i remembered a method to do branchless abs.
>> can i send it as a patch?

Nice :-)

> more code is more work, especially with platform
> specific assembly. is there any real world program
> where this matters a lot?

On top of having quantitative data (i.e.  a microbenchmark as well as
something real like a benchmark suite) available that show the benefit,
it would also be interesting what the compiler generates for
abs()/labs() and juxtapose that to see how much savings in code size,
improvement in performance, etc. this can accomplish.

That way it is easier to make the trade-off between maintainability
burden vs. performance gain.