pytorch

28740869 - Adds an aten::_ops namespace with unambiguous function names (#58092)

Adds an aten::_ops namespace with unambiguous function names (#58092) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/58092 Fixes #58044. This PR: - adds `ATEN_FN(op)` and `ATEN_FN2(op, overload)` macros that resolve to an non-overloaded function in aten::_ops that calls the desired operator (without default arguments). The motivation for this is two-fold: 1) Using aten operators with templates is hard if the operator is overloaded (e.g. add.Tensor and add.Scalar). 2) Method-only operators require special handling; pointers-to-method are different from function pointers. `ATEN_FN2(add_, Tensor)` returns a function instead of a method. There is some interesting behavior for out= operations. `ATEN_FN2(sin, "out")` gives a function that is *faithful* to the schema; that is, the order of arguments is exactly what it looks like in the schema. This makes it so that you can directly register `ATEN_FN2(sin,"out")` (or a function wrapping it using the same signature) as an override for a DispatchKey. Test Plan: - New tests that ATEN_FN2 works on function and method-only operators - New test that ATEN_FN works - New test that ATEN_FN macro returns a "faithful" function. Codegen output: Operators.h and Operators.cpp are both here: https://gist.github.com/zou3519/c2c6a900410b571f0d7d127019ca5175 Reviewed By: mruberry Differential Revision: D28643215 Pulled By: zou3519 fbshipit-source-id: 7b2b8459f1b2eb5ad01ee7b0d2bb77639f77940e