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:
Jan. 28, 2014
Filed:
Apr. 21, 2011
G. Glenn Henry, Austin, TX (US);
Terry Parks, Austin, TX (US);
Brent Bean, Austin, TX (US);
Thomas A. Crispin, Austin, TX (US);
G. Glenn Henry, Austin, TX (US);
Terry Parks, Austin, TX (US);
Brent Bean, Austin, TX (US);
Thomas A. Crispin, Austin, TX (US);
VIA Technologies, Inc., New Taipei, TW;
Abstract
A microprocessor includes a storage element that stores decryption key data and a fetch unit that fetches and decrypts program instructions using a value of the decryption key data stored in the storage element. The fetch unit fetches an instance of a branch and switch key instruction and decrypts it using a first value of the decryption key data stored in the storage element. If the branch is taken, the microprocessor loads the storage element with a second value of the decryption key data for subsequent use by the fetch unit to decrypt an instruction fetched at a target address specified by the branch and switch key instruction. If the branch is not taken, the microprocessor retains the first value of the decryption key data in the storage element for subsequent use by the fetch unit to decrypt an instruction sequentially following the branch and switch key instruction.