Store source, not sname, in Symbol (#91057)
I'm going to need this in the follow up PR. Instead of storing only Source.name() in Symbol, I now store a full on Source. Lots of replumbing reoccurs. In particular:
- Move Source to torch._guards to break cycles
- I have to add TensorPropertySource and NegateSource to handle x.size()[0] and -x codegen that I was doing with string manipulation previously
- I tighten up invariants so that I never pass source=None; instead I pass ConstantSource (these are constant sources right) and test for that rather than source being missing. I think this is more parsimonious
- Some mypy wobbles from new imports
I didn't move LocalSource and friends to torch._guards, but I ended up needing to access them in a few places. The main annoyance with moving these is that then I also need to move the bytecode codegen stuff, and that's not so easy to move without bringing in the kitchen sink.
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/91057
Approved by: https://github.com/albanD, https://github.com/voznesenskym, https://github.com/zou3519
