Re: [boost] Back to Boost.SIMD - Some performances ...

Subject: Re: [boost] Back to Boost.SIMD - Some performances ...
From: Stephan Tolksdorf (andorxor_at_[hidden])
Date: 2009-03-26 15:26:58

Joel Falcou wrote:
> Stephan Tolksdorf a écrit :
>> you think the library will provide competitive performance for the 
>> specific vector sizes of N=1,2,3,4?
> Well, Boost.SIMD has a different scope. It provides pervasive acces to
> SIMD facility (SIMD vector of 1 element are rather useless)
> vector of 2 and 4 that can be mapped on proper native intrinsic type
> will benefit from SIMD acceleration, other will benefit from agressive
> inlining of boost::array.

An efficient and well tested scalar math library as the by-product of a 
generic SIMD vector library certainly wouldn't be useless, and I'd guess 
that an SSE scalar implementation would look pretty similar to the SSE 
vector implementation...

>> BTW, are you aware of the Eigen library: http://eigen.tuxfamily.org
> Well, considering my PHD thesis was writing such a library I am.
> I send you back the question, are you aware of NT2 :
> http://nt2.sourceforge.net ?
 >
 > cause it's the project this Boost.SIMD is actually extarcted from ;)

I obviously wasn't. It's a bit unfortunate that there are so many parallel 
development efforts in the area of template libraries for linear algebra: 
ublas, mtl, eigen, nt2...

Have you thought about joining efforts with the Eigen guys? I'm no expert 
in this area, but their benchmark numbers look pretty compelling and the 
API seems to support fixed-size vectors in an elegant way. There would 
probably be huge economies of scale if the C++ community converged towards 
a single template matrix library.

Stephan