[Static Runtime] Remove ProcessedNode::num_outputs_ (#72592)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/72592
Only code paths that are not perf-critical read `ProcessedNode::num_outputs_` and also its static feature of the op that `ProcessedNode` instance is executing.
Therefore, it's better to move `ProcessedNode::num_outputs_` into `ProcessedFunction::num_outputs_` and let `ProcessedNode` access it via `ProcessedNode::fn_` for its occasional use. Note that this prevents duplicating num_outputs_ per node & per Static Runtime instance since `ProcessedFunction` instances are shared across all runtime instances.
It's confirmed that this change reduces the `sizeof(ProcessedNode)` by 14% from local instrumentation as follows:
- Before
-- sizeof(ProcessedNode): 56
- After
-- sizeof(Processednode): 48
Test Plan: `buck test //caffe2/benchmarks/static_runtime:static_runtime_cpptest`
Reviewed By: mikeiovine
Differential Revision: D33984792
fbshipit-source-id: e29ffc97b799e679215f42e1e85cd3fcd7e88983
(cherry picked from commit 0f7003f4dfd6473a70355ca3c6f51498abf1d7be)
