How does branch prediction work?

Can you explain how branch prediction works in CPUs?

Sure! Branch prediction is a technique used in CPUs to improve the flow of instruction execution. It guesses the direction of a branch (like an if statement) before it's actually known.

Why is branch prediction important for performance?

It's crucial because it helps reduce the number of stalls in the pipeline. If the CPU can predict the outcome of a branch correctly, it can continue executing instructions without waiting.

What happens if the prediction is wrong?

If the prediction is wrong, the CPU has to flush the pipeline, which means it discards the incorrectly executed instructions and starts over with the correct path. This can lead to performance penalties.

Are there different types of branch predictors?

Yes, there are several types, including static and dynamic predictors. Static predictors use fixed rules, while dynamic predictors adapt based on the history of branch outcomes.