alt Hacker NewsHow so? I imagine you'd still want to constrain the length to the maximum vector size supported by the lowest platform you want to support or you lose the portability and actually end up with code that performs much worse than the scalar alternative on some platforms.
Mojo has an even more portable simd[1] type that isn't just generic over length but also over type. In my opinion it is almost always better to specialize for each platform and use portable implementation as fallback. It's a shame that just very few languages support Zig-like comptime, because it would be excellent for specializations without introducing runtime penalties.
> constrain the length to the maximum vector size supported by the lowest platform you want to support or you lose the portability and actually end up with code that performs much worse than the scalar alternative on some platforms.
Or, put a dynamic factor into your vector size and design everything around it. Such that every platforms can plug in their own factor and _scale_ the size of vectors. This is basically what LLVM IR does for SVE and RVV: `<vscale x 4 x i32>` where vscale is the said dynamic factor. Though the exact value of vscale is only known during runtime, it doesn't matter -- we still can design compiler optimizations and lowering around it. The generated binaries can then be portable across platforms with different vscale values.