From: jean.boussier@... Date: 2020-01-08T14:22:29+00:00 Subject: [ruby-core:96712] [Ruby master Misc#16487] Potential for SIMD usage in ruby-core Issue #16487 has been updated by byroot (Jean Boussier). SIMD Everywhere seem very interesting, but from a quick check it seems that all the fallbacks are applied during compilation, which means you'd have to compile ruby yourself to get the benefits. If we want most users to benefits from the speedups, we need to a test at runtime like PHP does: - https://github.com/php/php-src/blob/e73cc44021a6549b0382bda90a0f4274c1722b24/Zend/zend_cpuinfo.h#L27 - https://github.com/php/php-src/blob/aadd3aaed902a8f21c11984687a4e3d414a2caed/ext/standard/string.c#L3672-L3677 ---------------------------------------- Misc #16487: Potential for SIMD usage in ruby-core https://bugs.ruby-lang.org/issues/16487#change-83700 * 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: