pytorch

08df4c2b - slow_conv2d grad_input: avoid dispatch in parallel region (#65725)

slow_conv2d grad_input: avoid dispatch in parallel region (#65725) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/65725 See gh-56794 Avoid dispatch inside of parallel_for by: 1. Replacing Tensor slicing with TensorAccessor 2. Call `grad_input.zero_()` only once, outside of the parallel region 3. Replace `at::mm` with a `gemm` call Test Plan: Imported from OSS Reviewed By: saketh-are Differential Revision: D31257876 Pulled By: ngimel fbshipit-source-id: f2902edeccd161431c1dfb1ab3e165d039ec259d