Replace all direct cdata access with THPVariable_Unpack (#55799)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/55799
I'm going to change the implementation of cdata soon so I need to
abstract over cdata access with a function. Additionally, many
users are casting manually casting to THPVariable to access
the member so I can remove these unsafe casts in the client code
(the implementation, of course, is still doing an unsafe cast.)
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Test Plan: Imported from OSS
Reviewed By: albanD
Differential Revision: D27712130
Pulled By: ezyang
fbshipit-source-id: 95fcc013bf3913d67f2c634068eb5b3aab144cb3
