From: shyouhei@... Date: 2020-01-09T05:29:47+00:00 Subject: [ruby-core:96726] [Ruby master Misc#16487] Potential for SIMD usage in ruby-core Issue #16487 has been updated by shyouhei (Shyouhei Urabe). I would like to support this. The linked pull request shows 20x speed up for `coderange_scan`, which is definitely worth the hustle. Of course decreased portability & maintainability are problems. We have to somehow handle them. Let's discuss that. But every optimization must come with increased complexity and vectorization is just another example of it. If an optimization is effective enough compared to its cost (and I think that is the case here), I believe we should do that. ---------------------------------------- Misc #16487: Potential for SIMD usage in ruby-core https://bugs.ruby-lang.org/issues/16487#change-83716 * Author: byroot (Jean Boussier) * Status: Open * Priority: Normal * Assignee: ---------------------------------------- ### Context There are several ruby core methods that could be optimized with the use of SIMD instructions. I experimented a bit on `coderange_scan` https://github.com/Shopify/ruby/pull/2, and Pavel Rosick� experimented on `String#strip` https://github.com/ruby/ruby/pull/2815. ### Problem The downside of SIMD instructions is that they are not universally available. So it means maintaining several versions of the same code, and switching them either statically or dynamically. And since most Ruby users use precompiled binaries from repositories and such, it would need to be dynamic if we want most users to benefit from it. So it's not exactly "free speed", as it means a complexified codebase. ### Question So the question is to know wether ruby-core is open to patches using SIMD instructions ? And if so under which conditions. cc @shyouhei -- https://bugs.ruby-lang.org/ Unsubscribe: