Refactor convolution_backward's CudaDepthwise3d case (#71490)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/71490
Deleted unnecessary .contiguous() calls in convolution_backward. The
CudaDepthwise3d case always hits _depthwise_3d_backward_cuda_out,
which will make arguments contiguous as necessary.
Changed _depthwise_3d_backward_cuda_out
- to make the input contiguous only when we're computing grad_weight
- to make the weight contiguous only when we're computing grad_input
Test Plan: - pytest test/test_nn.py -v -k "conv"
Reviewed By: jbschlosser
Differential Revision: D33664696
Pulled By: zou3519
fbshipit-source-id: d01d4f213e21ef4778de089a158933737b191cdf
(cherry picked from commit c6eb977c94a07f9812567a43b125b453eb5c5051)
