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    Designing a SIMD Algorithm from Scratch performance rust mcyoung.xyz
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      valpackett avatar valpackett

      Doing [runtime detection] correctly is very hard and something I don’t particularly want to dig deeply into here.

      It’s kinda not that hard, especially not in Rust which gives you #[target_feature(..)] and std::arch macros (sadly doesn’t make it easy to use ifuncs instead of if statements but oh well the benefit from rtld-time resolution shouldn’t be that big performance wise)

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        5d22b avatar 5d22b

        sadly doesn’t make it easy to use ifuncs instead of if statements

        There is ifunky. The much more widely used memchr does something similar, though I suppose that doesn’t count as easy.

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          valpackett avatar valpackett

          “without the need for loader support” yeah those aren’t really it either.

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          winter avatar winter

          Don’t you use cfg_feature_enabled for runtime feature detection, and target_feature for compile-time feature detection?

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            valpackett avatar valpackett

            It’s not compile-time detection, it enables that feature for codegen inside of a function.

        3. dist1ll avatar dist1ll edited

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