Pipelined prefetcher for parallel advancement of multiple data streams

Abstract

A processor includes a front end to decode instructions, an execution unit to execute instructions, multiple caches at different cache hierarchy levels, a pipelined prefetcher, and a retirement unit to retire instructions. The prefetcher includes circuitry to receive a demand request for data at a first address within a first line in a memory and, in response, to provide the data at the first address to the execution unit for consumption, to prefetch a second line at a first offset distance from the first line into a mid-level cache, and to prefetch a third line at a second offset distance from the second line into a last-level cache. The prefetcher includes circuitry to prefetch, in response to another demand request, the third line into the mid-level cache, and a fourth line into the last-level cache. The prefetcher enforces minimum or maximum offset distances between prefetched data streams.