Re: [eigen] How do you link multiple versions (e.g. AVX vs SSE) of the same Eigen code?

[Benoit Jacob <jacob.benoit.1@xxxxxxxxx>]

2015-01-28 10:45 GMT-05:00 Christoph Hertzberg <chtz@xxxxxxxxxxxxxxxxxxxxxxxx>:

Matrix4f is an important question. Are there AVX instructions to make it worth aligning it to 32 bytes? If so, also for operations such as Matrix4f * Vector4f?
An analogue question is if we can profit from vectorization for Matrix2f and SSE. E.g., a Matrix2f*Matrix2f product could be done with some shuffling, two pmuls and one padd (last time I checked, this product was not vectorized). Also, Matrix2f*Vector2f should be possible with some shuffling, one pmul and one hadd (and then storing only 8bytes of the result vector)

You're right, I was missing how AVX could be useful for smaller float cases, but that could be very interesting indeed.

Benoit

 

Christoph

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Dipl.-Inf., Dipl.-Math. Christoph Hertzberg
Cartesium 0.049
Universität Bremen
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