Branchless implementation for literal case – is it worth it?

Joachim Breitner mail at joachim-breitner.de
Mon Apr 20 14:41:00 UTC 2015


Hi,

Am Montag, den 20.04.2015, 16:29 +0200 schrieb Sven Panne:
> 2015-04-19 9:44 GMT+02:00 Joachim Breitner <mail at joachim-breitner.de>:
> > [...] So my question to the general audience: Is such branchless code really
> > better than the current, branching code? Can someone provide us with an
> > example that shows that it is better? Do I need to produce different
> > branchless assembly? [...]
> 
> Just a few war stories regarding this from the trenches (= Chrome's
> JavaScript JIT):

thanks a lot.

The conclusion I draw from your mail, at last for our case, is:
Don’t bother (and keep the compiler code simple). Is that a correct
reading?

Greetings,
Joachim


-- 
Joachim “nomeata” Breitner
  mail at joachim-breitner.dehttp://www.joachim-breitner.de/
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  Debian Developer: nomeata at debian.org
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