Re: [eigen] Eigen containers cannot be vectorized

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To: eigen@xxxxxxxxxxxxxxxxxxx
Subject: Re: [eigen] Eigen containers cannot be vectorized
From: Matthieu Brucher <matthieu.brucher@xxxxxxxxx>
Date: Thu, 8 Dec 2016 15:02:18 +0000
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Interesting analysis!

I would draw a different conclusion from it though: compiler auto-vectorization is hopeless :-)

Which is why explicitly-vectorized code like Eigen exists :-)

Explicitely vectorized code is good for compilers that are bad at auto vectorizing code (gcc, VS...). The drawback is that you can't use cpu dispatch easily to accomodate several optimized path for different CPUs.

Cheers,

Matthieu

Information System Engineer, Ph.D.
Blog: http://blog.audio-tk.com/
LinkedIn: http://www.linkedin.com/in/matthieubrucher

References:
- [eigen] Eigen containers cannot be vectorized
  - From: Francois Fayard
- Re: [eigen] Eigen containers cannot be vectorized
  - From: Benoit Jacob

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