yade-dev team mailing list archive

[Anton Gladky <gladky.anton@xxxxxxxxx>]

Thanks for interesting information.
Is it better to avoid sqrt?
______________________________


Anton Gladkyy


2010/6/14 Václav Šmilauer <eudoxos@xxxxxxxx>

> FYI this is a file that evaluates cost of various ops when optimizing
> (for i386):
>
> http://repo.or.cz/w/official-gcc.git/blob/trunk:/gcc/config/i386/i386.c
>
> It is grouped by processor models; interesting is that (for core2
> family) sqrt costs 58, float division 32 (!), float multiplication 5
> (for AMD k8 processors, it is 35 for sqrt and 19 for fdiv).  (that
> doesn't mean that you should rewrite * to /, gcc is smart enough to
> precompute if used multiple times)
>
> Cheers, v.
>
>
>
>
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