Control unit of simple pipeline
Everything about the instruction is known at ID stage
If can pass from ID to EXE stage, the instruction is issued
Control unit and forwarding unit take care of RAW dependencies
Except for load dependencies taken care of by control and stall units
- To insert a bubble, zero out all control fields in relevant pipeline registers; also might need to prevent instruction fetch (signal preventing “read instruction memory”)
Stall (aka hazard detection) unit can also be used for control hazards