On Monday 19 January 2009 00:50, Dean Michael Berris wrote:
I agree, but if you're going to tackle the concurrency problem through a DSEL, I'd think a DSEL at a higher level than SIMD extensions would be more fruitful. For example, I'd think something like:
vector<huge_numbers> numbers; // populate numbers async_result_stream results = apply(numbers, [... insert funky parallelisable lambda construction ...]) while (results) { huge_number a; results >> a; cout << a << endl; }
Would be able to spawn thread pools, launch tasks, and provide an interface to getting the results using futures underneath. The domain experts who already know C++ will be able to express their funky parallelisable lambda construction and just know that when they use the facility it will do the necessary decomposition and parallelism as much as it can at the library level. This I think is something that is feasible (although a little hard) to achieve -- and to think that the compiler will even be able to vectorize an inner loop in the decomposed lambda construction, that detail isn't even necessarily dealt with by the library.
Indeed, I think something like this is the right approach. Intel's Thread Building Blocks is one attempt. I'm not saying it's the best but it's at least instructive. -Dave