GitLab

* Add a temporary workaround to layernorm export

Seems like ORT is performing template-matching for LN and incorrectly concludes
that it doesn't have a kernel for FP32 LN. The work-around adds the addition of
fake_zero which is meant to prevent the template matching while keeping the graph
virtually unchanged. This also requires `do_constant_folding=False` in
`torch.onnx.export`.
Signed-off-by: Neta Zmora <nzmora@nvidia.com>

* Adjust test threshold
Signed-off-by: Neta Zmora <nzmora@nvidia.com>

* Opened an ORT bug and added the link for tracking
Signed-off-by: Neta Zmora <nzmora@nvidia.com>

* Fix Python linter errors
Signed-off-by: Neta Zmora <nzmora@nvidia.com>

* Simplify the LN workaround solution (ONNX export)

After discussing https://github.com/microsoft/onnxruntime/issues/15021


with Microsoft engineers, replaced the LN workaround with a simpler
implementation.

In addition:
* To make test more robust add `allow_cnt_errors` to `validate_result`
* Add more documentation to clarify the purpose and methodology of the
ONNX export tests
Signed-off-by: Neta Zmora <nzmora@nvidia.com>

* Fix unused import
Signed-off-by: Tim Moon <4406448+timmoon10@users.noreply.github.com>

* Fix unused import
Signed-off-by: Tim Moon <4406448+timmoon10@users.noreply.github.com>

* Fix unused import
Signed-off-by: Tim Moon <4406448+timmoon10@users.noreply.github.com>

---------
Signed-off-by: Neta Zmora <nzmora@nvidia.com>
Signed-off-by: Tim Moon <4406448+timmoon10@users.noreply.github.com>
Co-authored-by: Tim Moon <4406448+timmoon10@users.noreply.github.com>