Determining prefetch patterns with discontinuous strides

An apparatus comprising:

• processing circuitry to execute a stream of instructions comprising access instructions that access at least some data elements at given locations of a storage circuitry;
• training circuitry to determine a pattern of the given locations based on the access instructions;
• prefetch circuitry to perform prefetches based on the pattern, wherein
• the training circuitry comprises first stride calculation circuitry to calculate first stride lengths of the access instructions and to store the first stride lengths in a first stride length storage table in association with the access instructions, wherein discontinuous access instructions are identified as those of the access instructions where the first stride lengths calculated by the first stride calculation circuitry differ from what is stored for those access instructions in the first stride length storage table;
• the training circuitry comprises second stride calculation circuitry to calculate a second stride length based on the discontinuous access instructions that have been identified;
• the pattern is based on the second stride length;
• and
• in response to the first stride length calculated by the first stride calculation circuitry for a given access instruction differing from what is stored for the given access instruction in the first stride length storage table, the second stride calculation circuitry is adapted to be updated.