[PyTorch] Add tuple inline storage (#64066)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/64066
I noticed a bunch of time being spent heap-allocating Tuples
in the unpickler. 1-, 2-, and 3-element Tuples are apparently common
enough that they get their own bytecode instructions, so I decided to
try also giving them their own representation. We store up to 3
IValues inline in `Tuple` rather than doing a second heap allocation
for a `std::vector<IValue>`.
ghstack-source-id: 140695395
Test Plan:
Added automated tests for TupleElements.
Pixel 3 before: https://www.internalfb.com/intern/aibench/details/761596366576284
Pixel 3 after: https://www.internalfb.com/intern/aibench/details/591414145082422
We went from 347 ms to 302 ms.
Reviewed By: dhruvbird
Differential Revision: D30592622
fbshipit-source-id: 93625c54c9dca5f765ef6d5c191944179cb281a8
