Fixes for PyTorch/XLA functionalization integration (#94537)
Fixes for PyTorch/XLA functionalization integration
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Some notable changes include:
- More asserts in `FunctionalTensorWrapper`, so bugs show up more cleanly in cases where we e.g. forget to wrap an output
- Make the *_scatter ops `CompositeExplicitAutogradNonFunctional`, so we get a better error message and XLA doesn't accidentally try to us them
- Fix LTC/XLA codegen in core to handle multi-tensor out= ops with no returns
- Better erroring: Allow XLA to use the CPU fallback from core in a way so that it always errors on view ops, which XLA should no longer see.
- Update MetaConverter to exclude XLA tensors in raising NotImplemented…
- Add `_propagate_xla_data` op
- Add meta tensor support for some ops
Pull Request resolved: https://github.com/pytorch/pytorch/pull/94537
Approved by: https://github.com/bdhirsh
