Methods and apparatus for predicting instructions for execution

An apparatus comprising:

• prediction circuitry to predict instructions for execution, wherein said prediction circuitry comprises:
• a plurality of hierarchical prediction units, comprising a lowest level prediction unit and one or more higher level prediction units to:
• perform respective hierarchical predictions of each of the instructions for execution, wherein predictions higher in the hierarchy have a higher expected accuracy than predictions lower in the hierarchy;
• and
• responsive to a given prediction higher in the hierarchy being different from a corresponding prediction lower in the hierarchy, correct the corresponding prediction lower in the hierarchy, and
• a prediction correction metric determination unit to determine a prediction correction metric indicative of an incidence of uncorrected predictions performed by the prediction circuitry, the uncorrected predictions being predictions matching predictions of the one or more higher level prediction units, and
• fetch circuitry to fetch instructions for execution, the fetch circuitry being configured to:
• fetch instructions predicted by at least one of said plurality of hierarchical predictions;
• and
• in response to the prediction correction metric indicating an incidence of said uncorrected predictions being below a threshold, applying a delay before said fetching.