[PyTorch] NotImplementedError: The following operators are not implemented: ['aten::stft']

[thecooltechguy]

Hi,

When I try to compile a Pytorch model that uses torch.stft, I'm getting the following error.

NotImplementedError: The following operators are not implemented: ['aten::stft']

Will this operator be supported within Apache TVM?

Thanks!

[masahi]

This is hard to support, since it probably involves FFT, which is a very challenging op to implement and optimize.

[zuowanbushiwo]

@masahi @jsheng-jian TVM currently has stft operator, but why not fft, ifft, istft? Thanks!

[masahi]

stft added in #11190 is implemented in a very naive way (exactly like textbook 1D convolution). I think istft is easy using the similar approach, but fft / ifft with O(nlogn) complexity would be much more challenging.