pytorch

4132c1c5 - [Static Runtime] Add pass to eliminate __getitem__/DictConstruct calls (#62429)

[Static Runtime] Add pass to eliminate __getitem__/DictConstruct calls (#62429) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/62429 Introduce a new pass to eliminate calls to `prim::DictConstruct/aten::__getitem__`. Given a graph like this: ``` %2 : Dict = prim::DictConstruct(%key, %value) %3 : Tensor = aten::__getitem__(%2, %key) %4 : Tensor = op(%3) ``` This pass produces a graph like this (after dead code elimination): ``` %4 : Tensor = op(%value) ``` This optimization is applied in the static runtime. Test Plan: `buck test //caffe2/test:jit -- TestPeephole` **local.forward performance summary** About 3% runtime benefit. All `DictConstruct` calls optimized out, `__getitem__` calls reduced significantly (~50% of them are cut out) P438354810 **local_request_only.forward performance summary** About 14% runtime benefit. Again, all `DictConstruct` calls optimized out, 50% `__getitem__` calls removed. P438359742 There is some variance with runtime measurements, so take these numbers with a grain of salt. Also note that the benefit does not exist in the shrunk model since there are no `DictConstruct` calls Reviewed By: hlu1 Differential Revision: D29995087 fbshipit-source-id: f376376a46ff808115afd2d60446e5db8f6f752f