Replace empty with new_empty in nn.functional.pad (#68565)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/68565
This makes it so that we can now vmap over nn.functional.pad (circular
variant). Previously we could not because we were effectively doing
`out.copy_(input)` where the out was created with empty.
This also has the added side effect of cleaning up the code.
Test Plan:
- I tested this using functorch.vmap and can confirm that vmap now
works.
- Unfortunately this doesn't work with the vmap in core so I cannot add
a test for this here.
Reviewed By: albanD
Differential Revision: D32520188
Pulled By: zou3519
fbshipit-source-id: 780a7e8207d7c45fcba645730a5803733ebfd7be
