pytorch

d168a853 - compare scalar device with common device (#21236)

compare scalar device with common device (#21236) Summary: I think there was a typo in #20690 here https://github.com/pytorch/pytorch/pull/20690/files#diff-b47a50873394e38a005b4c1acd151957R130. Original conditional was ` common_backend == Backend::CUDA && op.tensor.type().backend() == Backend::CPU)`, now it is `op.device.is_cuda() && op.tensor.device().is_cpu()`. It seems that `op.device` and `op.tensor.device()` should be the same, so this conditional is never true. This leads to spurious h2d copies for operations between cuda tensors and cpu scalars, because cpu scalars are now sent to gpu, instead of being passed to lambdas directly. Unfortunately, I don't know how to test this change, because functionally everything was fine after #20690, it was just a performance regression. cc colesbury Pull Request resolved: https://github.com/pytorch/pytorch/pull/21236 Differential Revision: D15592754 Pulled By: soumith fbshipit-source-id: 105bfecc61c222cfdb7294a03c9ecae3cc7f5817