[ONNX] Adding ONNX large model export support in exporter (#33062)
Summary:
There are large models such as GPT2-large which cannot be exported with the current exporter because of the 2GB protobuf limit (e.g. see https://github.com/pytorch/pytorch/issues/19277). ONNX spec specifies a special format for large (> 2GB) models. This PR adds support for exporting large models in ONNX large model format in the PyTorch-ONNX exporter.
This is the first PR for this feature that enables the end-to-end execution. Tests for large model export have been added. We may need follow-up PRs to refine this workflow based on user feedback.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/33062
Reviewed By: hl475
Differential Revision: D19782292
Pulled By: houseroad
fbshipit-source-id: e972fcb066065cae6336aa91c03023d9c41c88bd
