Patent · US Expired

Pipelined processor with two tier prefetch buffer structure and method with bypass

US5680564A · kind A · utility

54Cited by
11References
31Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 26, 1995
Grant dateOct 21, 1997
Priority date
Expiry dateMay 26, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/3802
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.