Reduce overhead of OnnxifiOp (#20085)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/20085
Reduce the overhead of OnnxifiOp from ~40us avg (~100us max) to ~25us avg (~40us max).
Reviewed By: bertmaher
Differential Revision: D15191071
fbshipit-source-id: 830d2bd08b19567a133d43c8a7b996032629d326
