In IR verifier check if any of the ops in the graph doesn't have a portable kernel

[larryliu0820]

🚀 The feature, motivation and pitch

Currently the verifier logic only makes sure we have core ATen ops in the graph:

https://github.com/pytorch/executorch/blob/main/exir/verification/verifier.py#L126

The problem with this is that we still don't have 100% coverage of core ATen ops in portable kernel library (our default kernel library) so that even the verifier is happy it might run into issues when we run the .pte file in the runtime.

For example as of now adaptive_avgpool is marked as core but doesn't have portable kernel.

We want to enhance the verifier to give out warnings when this happens. We don't want to error out because it might be the case where user has a custom kernel library and is able to run this op.

Alternatives

No response

Additional context

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RFC (Optional)

No response

cc @JacobSzwejbka @angelayi

[mcremon-meta]

Thanks @larryliu0820! +1, that would be very helpful to avoid runtime errors which could be caught at compile time :)