Definition
Predicted Branch
A predicted branch is a branch instruction for which the processor has already made a prediction about whether the branch will be taken and, if needed, what the next target address is.
This prediction is used so that instruction fetch can continue before the actual branch outcome is known.
Role
Why prediction is used
In a pipelined processor, the actual outcome of a branch may only be known in a later stage, often the execute stage.
Predicting the branch allows the processor to keep the pipeline busy instead of waiting.
If the prediction is wrong, the wrong-path instructions must be flushed, causing a branch misprediction penalty.