Implement more size-oriented opcodes in the depickler. (#25786)
Summary:
These are intentionally not yet used by the encoder to
avoid backcompat issues.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/25786
Differential Revision: D17374409
fbshipit-source-id: 17971b26e48429c68b7fa8126d7ed56ff80b5d68
