pytorch

3e9cbe5e - [SPMD] Remove the code branches only used in SPMD mode from distributed.py (#55353)

[SPMD] Remove the code branches only used in SPMD mode from distributed.py (#55353) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/55353 Remove all the code branches that will only be executed when `device_ids > 1`. Some helper functions are also removed: 1. `_verify_replicas_within_process` and `verify_replicas_within_process` 2. `_replicate_modules_within_process` 3. `parallel_apply` The next step is deprecating `_module_copies` field. ghstack-source-id: 126201121 Test Plan: waitforbuildbot Reviewed By: rohan-varma Differential Revision: D27552201 fbshipit-source-id: 128d0216a202f5b1ba4279517d68c3badba92a6c