Patent · US Expired

Methods and apparatus for controlling speculative execution of instructions based on a multiaccess memory condition

US6877088B2 · kind B2 · utility

39Cited by
7References
32Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 3, 2002
Grant dateApr 5, 2005
Priority date
Expiry dateJun 19, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D10/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Mechanisms and techniques operate in a computerized device to enable or disable speculative execution of instructions such as reordering of load and store instructions a multiprocessing computerized device. The mechanisms and techniques provide a speculative execution controller that can detect a multiaccess memory condition between the first and second processors, such as concurrent access to shared data pages via page table entries. This can be done by monitoring page table entry accesses by other processors. The speculative execution controller sets a value of a speculation indicator in the memory system based on the multiaccess memory condition. If the value of the speculation indicator indicates that speculative execution of instructions is allowed in the computerized device, the speculative execution controller allows speculative execution of instructions in at least one of the first and second processors in the computerized device. If the value of the speculation indicator indicates that speculative execution of instructions is not allowed in the computerized device, the speculative execution controller does not allow speculative execution of instructions.

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