pytorch

eea53574 - Add bfloat16 support for nccl path (#38515)

Add bfloat16 support for nccl path (#38515) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/38515 Differential Revision: D22420896 Pulled By: ezyang fbshipit-source-id: 80d2d0c2052c91c9035e1e025ebb14e210cb0100