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:
Dec. 20, 2011
Filed:
Mar. 30, 2009
Tetsuya Yamada, Sagamihara, JP;
Naoki Kato, Kodaira, JP;
Kesami Hagiwara, Koganel, JP;
Renesas Electronics Corporation, Kawasaki-shi, JP;
Abstract
There is a need for providing a data processor capable of easily prefetching data from a wide range. A central processing unit is capable of performing a specified instruction that adds an offset to a value of a register to generate an effective address for data. This register can be assigned an intended value in accordance with execution of an instruction. A buffer maintains part of instruction streams and data streams stored in memory. The buffer includes cache memories for storing the instruction stream and the data stream. From the memory, the buffer prefetches a data stream containing data corresponding to an effective address designated by the specified instruction stored in the cache memory. A data prefetch operation is easy because a data stream is prefetched by finding the specified instruction from the fetched instruction stream. Data can be prefetched from a wider range than the use of a PC-relative load instruction.