Deny list for a memory prefetcher circuit

US12306762B1 · kind B1 · utility

Assignee

• Apple Inc. · US

Inventors

• Tyler J. Huberty · Sunnyvale, US
• Eric J. Furbish · Austin, US
• Mridul Agarwal · Sunnyvale, US
• Peter G. Soderquist · Milford, US
• Sandeep Gupta · Fremont, US
• Stephen G. Meier · Los Altos, US
• Vivek Venkatraman · Irvine, US
• Yanran Yang · Sunnyvale, US
• Sahil Kapoor · Sunnyvale, US
• Chandan Shantharaj · San Jose, US

Key dates

• Filing date: May 24, 2023
• Grant date: May 20, 2025
• Expiry date: May 26, 2043

Classification

• Technology area (CPC G): Physics
• CPC primary: G06F2212/602
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

An apparatus includes a cache memory circuit, a prefetcher circuit, and a prefetch deny list circuit, including a plurality of entries, may be included. The cache memory circuit may be configured to store information retrieved from a lower-level memory. The prefetcher circuit may be configured to generate a prefetch request for a particular prefetch address. The prefetch deny list circuit may be configured to allocate, in response to an indication from the cache memory circuit that a previously prefetched address went unused, a given entry, of the plurality of entries, for the previously prefetched address. The prefetch deny list circuit may be further configured to determine whether a particular address for a particular prefetch request corresponds to an active one of the plurality of entries. In response to a determination that a particular active entry corresponds to the particular address, prefetch deny list circuit may deny the particular prefetch request.