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0 pointsConst-me7y ago0 comments

> that doesn't have to be rewritten for a different architecture

CPU architectures are quite stable. SSE2 is almost 20 years old now. You can't even run modern Windows on a system which doesn't support it.

Vectorize to SSE and you'll get your 50% of potential performance. You can do it without any new paradigms, C and C++ support SSE intrinsics for decades already, other languages are catching up.

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atq21197y ago

I thought it was obvious, but apparently I wasn't clear enough: what I meant with the need for rewrite is the need for rewrite to benefit from architectural changes.

If you wrote SSE2 code 20 years ago, then yes, it's still going to run. But it's not going to benefit from the advances made with AVX and AVX2.

Compare this to the GPU model, or ispc or vector instructions, where you automatically benefit from a wider machine without a rewrite of your code (and in the case of vector instructions even without a recompile).

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