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by unnouinceput 1481 days ago
Quote: "Today we're sharing open source code that can sort arrays of numbers about ten times as fast as the C++ std::sort...." and proceeds to explain about SIMD instructions.

Well, to me sounds that C++ std::sort is simply lacking an optimization which can very easy be implemented in next iteration of the compiler/linker. I had high hopes this would be a really breakthrough algorithm, not lack of a simple optimization using some instruction set that compiler/linker didn't implement. If they want, CPU vendors would make an even more awesome and faster instruction set, let's say SIMD2, which would leave this one in the dust.
1 comments
janwas 1481 days ago
CPU vendors have recently introduced SVE (Arm) and RVV (RISC-V) and we support those in Highway and thus also vqsort.

It's definitely interesting to discuss std::sort benefitting from such optimizations, but "very easy" seems rather optimistic.

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benstrumental 1481 days ago
Do you expect these optimizations making their way into std::sort eventually?
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janwas 1479 days ago
It depends on the goals of the library maintainers. Users who really care about speed may already be using another library such as PDQsort or ips4o. Given that, the stdlib maintainers may reason that adding code and 'complexity' (not all developers understand or are able to maintain SIMD) is not worthwhile.

Conversely, they may prefer to work towards the standard library being the fastest known way of doing things. This is now much more feasible given the single portable implementation, vs. having to rewrite thousands of lines for six instruction sets.

Not sure which consideration carries more weight.

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