The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 03, 2022
Filed:
Oct. 25, 2019
Apple Inc., Cupertino, CA (US);
Steven A. Myers, San Jose, CA (US);
Jeffry E. Gonion, Campbell, CA (US);
Yannick L. Sierra, San Francisco, CA (US);
Thomas Icart, Paris, FR;
Apple Inc., Cupertino, CA (US);
Abstract
Techniques are disclosed relating to protecting branch prediction information. In various embodiments, an integrated circuit includes branch prediction logic having a table that maintains a plurality of entries storing encrypted target address information for branch instructions. The branch prediction logic is configured to receive machine context information for a branch instruction having a target address being predicted by the branch prediction logic, the machine context information including a program counter associated with the branch instruction. The branch prediction logic is configured to use the machine context information to decrypt encrypted target address information stored in one of the plurality of entries identified based on the program counter. In some embodiments, the branch prediction logic decrypts the encrypted target address information by performing a cipher to encrypt the machine context information and performing a Boolean exclusive-OR operation of the encrypted machine context information and the encrypted target address information.