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:
Oct. 21, 1997
Filed:
May. 26, 1995
Robert James Divivier, San Jose, CA (US);
Mario Nemirovsky, San Jose, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A method and apparatus for prefetching instructions in a pipelined processor including first and second prefetch buffers arranged in a two tier system. As instruction bytes are fetched from cache memory or external memory, those instruction bytes from memory for which there is space in the first level buffer are loaded therein, and, simultaneously, those valid instruction bytes in the second tier buffer for which there is room in the first tier buffer are also loaded into the first tier buffer. Those instruction bytes from memory for which there is not currently room in the first tier buffer are loaded into the second tier buffer. The second tier buffer is also used as a buffer for loading the instruction cache memory from the external memory.