pytorch

2ab49701 - Add at::cpu namespace of functions for structured kernels (#49505)

Add at::cpu namespace of functions for structured kernels (#49505) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/49505 I have a problem which is that static runtime needs a way to bypass dispatch and call into kernels directly. Previously, it used native:: bindings to do this; but these bindings no longer exist for structured kernels! Enter at::cpu: a namespace of exactly at:: compatible functions that assume all of their arguments are CPU and non-autograd! The header looks like this: ``` namespace at { namespace cpu { CAFFE2_API Tensor & add_out(Tensor & out, const Tensor & self, const Tensor & other, Scalar alpha=1); CAFFE2_API Tensor add(const Tensor & self, const Tensor & other, Scalar alpha=1); CAFFE2_API Tensor & add_(Tensor & self, const Tensor & other, Scalar alpha=1); CAFFE2_API Tensor & upsample_nearest1d_out(Tensor & out, const Tensor & self, IntArrayRef output_size, c10::optional<double> scales=c10::nullopt); CAFFE2_API Tensor upsample_nearest1d(const Tensor & self, IntArrayRef output_size, c10::optional<double> scales=c10::nullopt); CAFFE2_API Tensor & upsample_nearest1d_backward_out(Tensor & grad_input, const Tensor & grad_output, IntArrayRef output_size, IntArrayRef input_size, c10::optional<double> scales=c10::nullopt); CAFFE2_API Tensor upsample_nearest1d_backward(const Tensor & grad_output, IntArrayRef output_size, IntArrayRef input_size, c10::optional<double> scales=c10::nullopt); }} ``` This slows down static runtime because these are not the "allow resize of nonzero tensor" variant binding (unlike the ones I had manually written). We can restore this: it's a matter of adding codegen smarts to do this, but I haven't done it just yet since it's marginally more complicated. In principle, non-structured kernels could get this treatment too. But, like an evil mastermind, I'm withholding it from this patch, as an extra carrot to get people to migrate to structured muahahahaha. Signed-off-by: Edward Z. Yang <ezyang@fb.com> Test Plan: Imported from OSS Reviewed By: smessmer Differential Revision: D25616105 Pulled By: ezyang fbshipit-source-id: 84955ae09d0b373ca1ed05e0e4e0074a18d1a0b5