Functionalization in PyTorch: Everything You Wanted To Know

[yskhhh]

@bdhirsh

Custom dispatcher ops. “functional” custom ops today with functionalization (any aliasing/mutation that is internal to the op is also ok), but we currently don’t support custom operators that have externally visible alias/mutation semantics (that mutate inputs, or return outputs that alias inputs).

I don’t understand this phrase. What does ‘externally visible alias/mutation semantics’ mean?