pytorch

457396fc - [Autograd] `expand_as` instead of `clone` to get `AccumulateGrad` (#96356)

[Autograd] `expand_as` instead of `clone` to get `AccumulateGrad` (#96356) This PR makes a minor change to the multi-grad hook implementation. This should decrease peak memory since we avoid one `clone()` per tensor passed into the multi-grad hook. Let me know if there are technical reasons why we need to clone. If so, is there a way for some use cases to not clone? Before with `clone()`:  After with `expand_as()` -- no more "Memcpy DtoD" kernels:  Pull Request resolved: https://github.com/pytorch/pytorch/pull/96356 Approved by: https://github.com/soulitzer