Patents Represented by Attorney, Agent or Law Firm David A. Plether
  • Patent number: 6430657
    Abstract: Atomic memory operations are provided by using exportable “fetch and add” instructions and by emulating IA-32 instructions prepended with a lock prefix. In accordance with the present invention, a CPU includes a default control register that includes IA-32 lock check enable bit (LC) that when set to “1”, causes an IA-32 atomic memory reference to raise an IA-32 intercept lock fault. An IA-32 intercept lock fault handler branches to appropriate code to atomically emulate the instruction. Furthermore, the present invention defines an exportable fetch and add (FETCHADD) instruction that reads a memory location indexed by a first register, places the contents read from the memory location into a second register, increments the value read from the memory location, and stores the sum back to the memory location.
    Type: Grant
    Filed: October 12, 1998
    Date of Patent: August 6, 2002
    Assignee: Institute for the Development of Emerging Architecture L.L.C.
    Inventors: Millind Mittal, Martin J. Whittaker, Gary N. Hammond, Jerome C. Huck