[Static Runtime] Implement prim::Fork and aten::wait (#78780)
Summary:
basic implementation of prim::fork and aten::wait
- current implementation uses interpreter to call the forked subgraph
- interpreter call to be replaced in future
- Added custom test cases for fork/wait procedures in the graph
Test Plan:
custom tests are created in test_static_runtime.py file for verification of static_runtime output compared to reference pytorch output.
test command
- buck run caffe2/test:static_runtime
- buck run caffe2/benchmarks/static_runtime:static_runtime_cpptest
- buck test caffe2/benchmarks/static_runtime/fb:test_fb_operators
Differential Revision: D36881214
Pull Request resolved: https://github.com/pytorch/pytorch/pull/78780
Approved by: https://github.com/tenpercent
