Execute (like Tomasulo)
Write
- Broadcast on common data bus the value and the tag (reorder buffer number). Reservation stations, if any match the tag, and reorder buffer (always) grab the value.
Commit
- When instr. at head of the reorder buffer has its result in the buffer it stores it in the real register (for ALU) or memory (for store) and is deleted. If the instruction is a branch with correct prediction, do nothing and delete. If the instruction is a branch with incorrect prediction, flush the buffer and restart with correct target address (do it as soon as possible).