Turn Instruction Overrides on JB's
Behaviour of TIOs on JBs:
- If there's a TIO from entry to 1st short segment, it will be used, and a TIO on the virtual segment (entry > exit) will be ignored
- if there's a TIO from any short segment to the next one, it will be used, and a TIO on the virtual segment will be ignored.
- Otherwise, if there is a TIO on the virtual segment, it will be used as the only instruction between entry and exit.