Patent · US Expired

Using a lockup processor to search a table of keys whose entries contain instruction pointer values of code to execute if key is found

US5774739A · kind A · utility

22Cited by
6References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 20, 1996
Grant dateJun 30, 1998
Priority date
Expiry dateSep 20, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/4843
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method for searching for keys of arbitrary width in a table in a memory of a computer system by repeatedly executing lookup instructions on a lookup processor. The lookup processor executes a lookup instruction to find a key in a table. The execution of the lookup instruction results in a key being found, or a key not being found. If the key is not found, the process is requeued by a scheduler with the program counter register for the process pointing to the instruction immediately following the lookup instruction, i.e., the next instruction. In the event the key is found in the table, the entry in the table associated with the key contains the memory address of the next instruction to be executed. This memory address is loaded into the program counter register associated with the process in which the lookup instruction was executed. The scheduler requeues the process, later dequeues it, and the instruction pointed to by the program counter register is fetched by an instruction fetch unit. A dispatcher sends the process to the appropriate processor for execution of the next instruction. In this way, a branch to any instruction in the process can be performed. The instruction poin…

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