LEVEL_TWO_REGISTER_DUMP
An instance of ContinuationRegisterDumpDescriptor, which holds a collection of AvailObject and Long values. These values are stored in the continuation for an L2Chunk to use as it wishes, but it's simply ignored when a chunk becomes invalid, since the unoptimizedChunk and its L1InstructionStepper always rely solely on the pure L1 state.
This slot can be nil if it's not needed.