Summary:
This functionality replaces the Scalar-Tensor builtin operators,
with builtin functions.
Builtin functions are used in place of operators where one operator
can be defined using a composition of another. This simplifies later
optimization passes by allowing us to have fewer operator.
In the future, builtin functions can be used for other purposes.
For example, we can define derivative functions as code rather than
building graphs.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/12141
Reviewed By: ezyang
Differential Revision: D10088065
Pulled By: zdevito
fbshipit-source-id: a2acb06346e649c4c8a2fe423b420871161c21cf
