[JIT] script & logging for extracting IR from logs (#72889)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/72889
The script along with the GRAPH_EXPORT macro will allow for an easy way to extract IR from logs. One use case in this diff is to extract the fusion groups from nvfuser, so that the fusions can be tested individually.
Usage (e.g. for nvfuser test)
1. Write some test.py file that uses nvfuser
2. `PYTORCH_JIT_LOG_LEVEL=">>graph_fuser" python3 test.py 2>&1 | tee output.txt`
3. `python3 pytorch/scripts/jit/log_extract.py output.txt --nvfuser`
This will run with and without nvfuser to compare the output.
Alternatively, use `--output` to dump the IR so that it can be used in other applications.
Currently, only `--output` works (since generating input tensors is not supported)
Test Plan: Imported from OSS
Reviewed By: ngimel
Differential Revision: D34440189
Pulled By: davidberard98
fbshipit-source-id: fca0f619200ee37aba34bb39b69e6c640c263e26
(cherry picked from commit eb319166075db160f1628f0de545641fbecde8be)
