free up dispatch key space (in C++) (#72402)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/72402
The original PR had an array-out-of-bounds access in `DispatchKeyExtractor.cpp`, that wasn't caught by ASAN and appeared to only manifest in a subset of android internal tests. After fixing the OOB access (and adding more asserts), I confirmed that the android internal test passes.
Reland of D33255193 (https://github.com/pytorch/pytorch/commit/20b8653dfaad495ba172b8116f540c258ef42ffe)
ghstack-source-id: 148830728
Test Plan:
Steps to test:
(1) connect to a mobile OD
(2) run `one_world android emulator android-29` in a terminal to start the android emulator
(3) In a separate terminal, run the test: `buck test //fbandroid/instrumentation_tests/com/facebook/pytorch/bi_xray:instrumentation_test -c test.external_runner=tpx -- --regex 'testBIXRayModel.*PyTorchBIXRayInstrumentationTest' --force-remote-execution --run-disabled`
I also ran `buck test fbandroid/mode/dbg //fbandroid/instrumentation_tests/com/facebook/pytorch/bi_xray:instrumentation_test`, which failed before and passed after the PR.
Reviewed By: albanD
Differential Revision: D34034848
fbshipit-source-id: 9677ee2c0a1afd1183896f7055009445712523c5
(cherry picked from commit 9ab9b12d355540ad0923c6869ed088ff6c21490c)
