To keep the size of BTAC small, only predicted taken branch addresses are stored.
- Effective with static prediction!
If the hardware alters the prediction direction due to the history of the branch, this kind of branch prediction is called dynamic branch prediction.
- Now the branch target address (of "taken") is stored also if the prediction direction may be "not taken".
- If the branch target address is removed for branches that are not taken? BTAC is better utilized.
- However branch target address must be newly computed if the prediction direction changes to "predict taken“.