Prediction of number of iterations of a fetching process

A method for an apparatus comprising processing circuitry to perform processing operations in response to decoded instructions, the method comprising:

• predicting, based on prediction state information, a number of iterations of a fetching process to be performed to control fetching of data or instructions to be used in processing operations that are predicted to be performed by the processing circuitry, where the processing circuitry is capable of tolerating performing one or more unnecessary iterations of the fetching process following an over-prediction of the number of iterations;
• and
• in response to the processing circuitry resolving an actual number of iterations of the fetching process, adjusting the prediction state information used to predict the number of iterations of the fetching process, based on whether a first predicted number of iterations, predicted based on a first iteration prediction parameter of the prediction state information, provides a good prediction or a misprediction;
• determining that the first predicted number provides the good prediction when the first predicted number of iterations is in a range i_cnt to i_cnt+N, where i_cnt is the actual number of iterations and N≥1;
• and
• determining that the first predicted number provides the misprediction when the first predicted number of iterations is outside the range i_cnt to i_cnt+N.

A non-transitory computer readable storage medium to store computer-readable code for fabrication of an apparatus comprising:

• processing circuitry to perform processing operations in response to decoded instructions;
• and
• prediction circuitry to predict, based on prediction state information, a number of iterations of a fetching process to be performed to control fetching of data or instructions to be used in processing operations that are predicted to be performed by the processing circuitry, where the processing circuitry is capable of tolerating performing one or more unnecessary iterations of the fetching process following an over-prediction of the number of iterations;
• in response to the processing circuitry resolving an actual number of iterations of the fetching process, the prediction circuitry is configured to adjust the prediction state information used to predict the number of iterations of the fetching process, based on whether a first predicted number of iterations, predicted based on a first iteration prediction parameter of the prediction state information, provides a good prediction or a misprediction;
• the prediction circuitry is configured to determine that the first predicted number provides the good prediction when the first predicted number of iterations is in a range i_cnt to i_cnt+N, where i_cnt is the actual number of iterations and N≥1;
• and
• the prediction circuitry is configured to determine that the first predicted number provides the misprediction when the first predicted number of iterations is outside the range i_cnt to i_cnt+N.