Data processing apparatus and method for providing candidate prediction entries

A method comprising:

• storing a plurality of prediction entries in a prediction cache, each of the plurality of prediction entries defining an association between a prediction cache lookup address and a predicted behaviour;
• selecting a prediction entry based on a prediction cache lookup of the prediction cache based on a given prediction cache lookup address;
• determining the predicted behaviour associated with the given prediction cache lookup address based on the selected prediction entry;
• and
• storing a plurality of entries, a given entry comprising information indicative of a candidate lookup address, information indicative of a candidate prediction cache lookup address and information indicative of a candidate predicted behaviour, the candidate prediction cache lookup address and the candidate predicted behaviour being indicative of a candidate prediction entry to be selected for inclusion in a subsequent prediction cache lookup,
• wherein a first entry comprises a first candidate prediction entry associating a first candidate prediction cache lookup address and a first candidate predicted behaviour, and the first candidate prediction entry is selected in response to a candidate prediction lookup in a candidate prediction buffer based on a comparison with information indicative of a first candidate lookup address in the first entry, wherein the first candidate lookup address is different from the first candidate prediction cache lookup address indicated as associated with the first candidate predicted behaviour in the first candidate prediction entry.

A data processing apparatus comprising:

• means for storing a plurality of prediction entries in a prediction cache, each of the plurality of prediction entries defining an association between a prediction cache lookup address and a predicted behaviour;
• means for selecting a prediction entry based on a prediction cache lookup of the prediction cache based on a given prediction cache lookup address;
• means for determining the predicted behaviour associated with the given prediction cache lookup address based on the selected prediction entry;
• and
• means for storing a plurality of entries, a given entry comprising information indicative of a candidate lookup address, information indicative of a candidate prediction cache lookup address, and information indicative of a candidate predicted behaviour, the candidate prediction cache lookup address and the candidate predicted behaviour being indicative of a candidate prediction entry to be selected for inclusion in a subsequent prediction cache lookup,
• wherein a first entry comprises a first candidate prediction entry associating a first candidate prediction cache lookup address and a first candidate predicted behaviour, and the first candidate prediction entry is selected in response to a candidate prediction lookup in the means for storing a plurality of candidate predictions based on a comparison with information indicative of a first candidate lookup address in the first entry, wherein the first candidate lookup address is different from the first candidate prediction cache lookup address indicated as associated with the first candidate predicted behaviour in the first candidate prediction entry.