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Libraries such as intel-MKL or amd-ACML provide easier interface to SIMD operations on vectors, but I want to chain several functions together. Are there readily available libraries where I can register a parse tree for an expression like

log( tanh(x) + exp(x) )

and then evaluate it on all members of an array ? What I want to avoid is to make a temporary arrays of tanh(x), exp(x) and tanh(x) + exp(x) by calling the mkl or acml functions for tanh(), exp() and +.

I can unroll the loop by hand and use the sse instructions directly, but was wondering if there are C++ libraries which does this for you, i.e. 

1. Handles SIMD/SSE functions  
2. Allows building of parse trees out of SIMD/SSE functions.

I am very much a newbie and have never used SSE or MKL/ACML before, just venturing out into new territory.

BЈовић
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san
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  • @VJo thanks for fixing the typos and reformatting the numbered list. – san Aug 10 '11 at 08:17
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    This is a bit of a tangent *snort, snort, ahem* but Wolfram Alpha has some optimization and simplification tools like `simplify log( tanh(x) + exp(x) )`] and they have an API too. Might be useful to some aspect of what you're doing, or not: http://blog.wolframalpha.com/2011/04/25/algebraic-simplification-simplifying-expressions-in-wolframalpha/ – HostileFork says dont trust SE Aug 10 '11 at 08:17

2 Answers2

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It may not do exactly what you want, but I suggest you take a look at macstl. It's a SIMD valarray implementation which uses template metaprogramming, and which can combine expressions into a single loop. You may be able to use this as is or perhaps as a basis for something closer to what you need.

Paul R
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Have a look at Intel ABB. It uses a just in time compilation approach IIRC. It can use vector instructions and multithreading depending on the sizes of the vectors you act upon.

Alexandre C.
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