fix alias annotations on to, cpu, cuda (#16460)
Summary:
Fix alias annotations for ops that may return a fresh tensor. The previous version was overly conservative.
Currently there is no actual behavior change in the alias analysis, but we may use the information in the future.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/16460
Differential Revision: D13849086
Pulled By: suo
fbshipit-source-id: cd23b314a800e5e077d866e74456d37a321439d5
