NNPACK with Windows support

[ghost]

Hi,

I've made a Windows port (re-)available (the old and currently unavailable zeno40/nnpack-windows repo) with a lot of improvements in CMake support and other kinds of cleanups. It still haves to bypass the FFT16x16 kernel in AVX2 with it psimd counterpart to get everything working:

https://github.com/zulma46/NNPACK

Thanks

[erip]

Is this something that would be possible to contribute back, @zulma46? Assuming @Maratyszcza is willing to accept the PR, this would be immensely helpful to address some Windows feature parity issues for PyTorch (and presumably other tools relying on NNPACK).

[Maratyszcza]

There are no plans to merge Windows support. My work is now focused on the XNNPACK project. XNNPACK supports Windows, and is integrated into PyTorch as well.

[erip]

@Maratyszcza unfortunately nnpack isn't optional for java bindings, which is the only remaining non-Windows compatible dependency

[larryliu0820]

In case people are still looking for windows support, I just submit a PR #201