pytorch

e8845540 - Make {select,slice,diagonal}_backward primitives wrt autograd (#64933)

Make {select,slice,diagonal}_backward primitives wrt autograd (#64933) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/64933 Fixes https://github.com/facebookresearch/functorch/issues/108 This is a short-term fix. A longer-term fix would be to either: 1. have proper {select,slice,diagonal}_embed functions 2. have efficient {select,slice,diagonal}_scatter functions (and efficient zero tensors). NB: I didn't use diag_embed because diag_embed is slightly different from diagonal_backward. There are no BC concerns because TorchScript (luckily) does not serialize the backwards graph. Test Plan: - run tests - run benchmarks. https://gist.github.com/zou3519/e7c0774d1ac97f32aa02ec44d81e60e1. Surprisingly the instruction count goes down. This is probably because we create fewer autograd nodes now. Reviewed By: ezyang Differential Revision: D30909333 Pulled By: zou3519 fbshipit-source-id: 3b33e13010ba13b4d487b346aa9bee8a0e8c378c