The (unsolicited) slop PRs on that repository are a sight to behold, though. The same slopper posted an aggressive response to my PR: https://github.com/Netflix/vmaf/pull/1586

... Oh by the way, did you know that Claude Code is actually a mini game engine? /s

for something like LLM inference, having this kind of abstraction seems like quite a hindrance

For example, you'll notice here that we perform a full vector store of 8 elements unconditionally, even if only a few of the elements are active. This is safe, though, because the output buffer is as large as the input buffer, and we're chunking by 8, so we'll never trash memory past the end; but this is a tricky analysis. Performance-wise, we rely on the CPU's store buffer to make these overlapping stores cheap.

Instead, you might think that you could just store the elements which are actually active, using a masked store. In fact there is also an intrinsic for this purpose (_mm512_mask_compressstoreu_pd), but it is extremely slow on some CPUs, namely Zen 4, so it's dangerous to use unless you know exactly what CPU you're using. (In my testing, there also seems to be some weird hazard on Zen 5 where multiple memory-destination compress instructions to nearby, even non-overlapping, addresses are serialized. But I haven't looked closer at this.)

You can do even a bit better if you're willing to use intrinsics. In particular this kind of operation is well-suited for compress-type operations, available as a first-class operation in at least AVX512, SVE and RVV; you can also emulate them reasonably quickly on NEON and AVX2.

Here's an example, building on the OP's work:

    pub fn filter_compress(input: &[f64], threshold: f64) -> Vec {
        use std::arch::x86_64::*;
    
        let mut out = vec![0.0; input.len()]; 
        let mut n = 0usize;
    
        let (head, tail) = input.as_chunks::<8>();
    
        for chunk in head {
            unsafe {
                let p = _mm512_loadu_pd(chunk.as_ptr());
                let m = _mm512_cmpnle_pd_mask(p, _mm512_set1_pd(threshold));
        
                let compress = _mm512_maskz_compress_pd(m, p); 
                _mm512_storeu_pd(out.as_mut_ptr().wrapping_add(n), compress);
                n += m.count_ones() as usize;
            }   
        }   
    
        for &x in tail {
            out[n] = x;
            n += (x > threshold) as usize;
        }   
        out.truncate(n);
        out 
    }

Anyway, I don't see how this relates to the original discussion. Nor do I think the irony is particularly deep: As far as I'm aware, Deep Blue didn't plagiarize Kasparov, and indeed alpha-beta search is quite different than how humans calculate. But yes, I'd have been very demoralized if I were Kasparov, although he seems to be doing well now.

Edit: Regarding being mean-spirited, sorry to say, but I don't particularly care for the feelings of someone who has been repeatedly dishonest and used LLMs to respond to people engaging in good faith. That latter path has been exhausted now.

To co-opt your conflation of legality and morality: free speech, mf!

Indeed, and this is the problem: unlike woodworking, where my power-assisted creation is independent of, or complements, your handcraft, this engine is directly competing with other engines. Twiss is being disingenuous when he says he has no interest in submitting it to competitions; it plays on a rated account on Lichess, for example.

But copyright and plagiarism are orthogonal, and questions of morality are much more tied to the latter. It would be illegal (in the United States) for me to publish a copy of Nineteen Eighty-Four, but not immoral. It was not immoral, in my view, for Aaron Swartz to try to liberate JSTor articles.

That doesn't make plagiarism acceptable, either. And therefore, I'm willing to call it out when I see it.

> The Cloudflare folks apparently want security issues reported via HackerOne (which wouldn’t let me log in because the Cloudflare CAPTCHA HackerOne uses seems to be broken…).

This part made me laugh out loud