kicad-developers team mailing list archive

[Cirilo Bernardo <cirilo_bernardo@xxxxxxxxx>]

>________________________________
> From: Carl Poirier <carl.poirier.2@xxxxxxxxx>
>To: Vesa Solonen <vesa.solonen@xxxxxxxx> 
>Cc: KiCad Developers <kicad-developers@xxxxxxxxxxxxxxxxxxx> 
>Sent: Thursday, January 23, 2014 4:41 AM
>Subject: Re: [Kicad-developers] Net names and net codes
> 
>
>
>Maybe. Having no experience whatsoever in vectorization, I'm looking into multithreading. Anyway, I believe one doesn't exclude the other.
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For over a year now, compiling with gcc (I can't remember the exact version of this change) with -O3 performs auto-vectorization. Unless you can see significant gain in structuring some loops so that the compiler algorithms can make a more efficient vectorization, just compile with -O3 and don't worry about it.

A little off topic: If -O3 shows up problems in some places (this is not uncommon with something as complex as an optimizing compiler) you can still attempt at a different optimization level and by using the explicit flags to enable vectorization. In cases where a compiler's vectorization code isn't working well and introducing bugs, then the only solution is to explicitly invoke the SIMD instructions ... and really, I see no reason for that and would simply disable auto-vectorization until the compiler is fixed.

- Cirilo