Pull instruction definitions out of interpreter.cpp. (#25148)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/25148
Instructions will be used in lite interpreter as well. Pull it out of interpreter.cpp, so that the lite interpreter doesn't have to compile with interpreter.cpp.
Test Plan: Imported from OSS
Differential Revision: D17076413
fbshipit-source-id: 99b3d8d27a96823a4a4dde6b2337ee44635e34cb
