Yes, it does beat -O3 C sometimes. I took code from diverse 'language speed' benchmarks from the internet and had to rearrange them to get -O3 to beat equivalent-looking JS (Node 25.8.1 w\ V8 14.1 and clang 21 on MBP3).
i've tried various options, Firefox prefers ` for (let i = n; i--;) out[i] = a[i] * b[i] + 0.25;`
Its already at peak optimization so no form is significantly better.
> What was that code?
literally:
``` function numericKernel(a, b, out, n) {
} ```