[Testing] Adding reference tests to `OpInfo` class (#59369)
Summary:
This PR will ideally add `ref` argument to `OpInfo` base class. The idea is to add reference checks for all the ops _eligible_. For more discussion, please check https://github.com/pytorch/pytorch/issues/58294
* [x] Migrate (but not removing yet) and modify helper functions from `UnaryUfuncOpInfo` class to `OpInfo` base class.
* [x] Test the reference checks for multiple ops. (also decide a list of different and eligible ops for this)
* [x] Handle possible edge cases (for example: `uint64` isn't implemented in PyTorch but is there in NumPy, and this needs to be handled -- more on this later) -- _Update_: We decided that these reference tests should only test for values and not types.
* [x] Create a sample PR for a single (of all different categories?) on adding reference functions to the eligible ops. -- _Update_: This is being done in this PR only.
* [x] ~Remove reference tests from `test_unary_ufuncs.py` and test to make sure that nothing breaks.~ (*Update*: We won't be touching Unary Ufunc reference tests in this PR)
* [x] Add comments, remove unnecessary prints/comments (added for debugging).
Note: To keep the PR description short, examples of edge cases encountered have been mentioned in the comments below.
cc: mruberry pmeier kshitij12345
Pull Request resolved: https://github.com/pytorch/pytorch/pull/59369
Reviewed By: ngimel
Differential Revision: D29347252
Pulled By: mruberry
fbshipit-source-id: 69719deddb1d23c53db45287a7e66c1bfe7e65bb
