[ublas] Re: SIMD?

From: Paul Baxter (pauljbaxter_at_[hidden])
Date: 2005-03-14 17:34:38

Am Montag, 14. März 2005 04:47 schrieb Tony Juricic:
>> Are there any SIMD (Altivec or SSE2) implementations considered in
>> UBLAS and new MTL projects?

>There is no explicit SIMD support, because uBLAS only consists of header
>files. Your compiler decides wheter it uses SSE2 or not.

I can recommend the fledgeling MacSTL library at www.pixelglow.com as a 
basis for providing cross-platform (Intel/Altivec) SIMD support though its 
license is not quite as flexible as Boost. (I think of it as 'author's gotta 
eat'-ware). Got a long way to go to be integrated with the likes of ublas 
though.

The PC side of things is not as mature as the Altivec, but Glen Low is 
working on it.

Whether he has any interest in extending things to ublas/MTL3 I don't know. 
Personally, I can't help feeling a combination of expression templates and 
SIMD instructions could be good for performance.

My initial comparisons of his valarray implementation against IPP/MKL-BLAS 
and standard library alternatives were encouraging albeit currently there is 
only limited type support on the PC.

I didn't bench ublas as my application is about manipulating 2D images so 
seems a better fit with image-processing style requirements.