Patents by Inventor Mark T. Vandevoorde

Mark T. Vandevoorde has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Processor performance counter for sampling the execution frequency of individual instructions
    Patent number: 6112317
    Abstract: A processor includes an execution pipeline and a retire unit coupled to an end of the execution pipeline. The processor executes instructions of a program. An apparatus for collecting performance data while the instructions are executing includes a register coupled to the retire unit of the processor. Means are provided for incrementing the register whenever an instruction is retired from the execution pipeline. In addition, the apparatus includes means for generating an interrupt to an interrupt handler whenever the register is incremented to a predetermined value.
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: August 29, 2000
    Assignee: Digital Equipment Corporation
    Inventors: Lance M. Berc, Shun-Tak Albert Leung, Mark T. Vandevoorde, William E. Weihl
  • Computer method and apparatus for analyzing program instructions executing in a computer system
    Patent number: 6009514
    Abstract: In a computerized method, performance data collected while a computer system executed instructions of a program are analyzed. The method collects performance data while executing the program. The performance data includes sample counts of instructions executed. The program is analyzed to determine classes of instructions. Instructions of the same equivalence class all execute the identical number of times. The execution frequencies for each instructions of each equivalence class is estimated. The estimated execution frequencies can then be used to determine the average number of cycles required to issue each instruction of each equivalence class. The average number of cycles can be compared with the minimum number of cycles to determine the number of dynamic stall cycles incurred by the instructions. Furthermore, reasons for the dynamic stall cycles can be inferred.
    Type: Grant
    Filed: October 30, 1998
    Date of Patent: December 28, 1999
    Assignee: Digital Equipment Corporation
    Inventors: Monika Hildegard Henzinger, Shun-Tak Albert Leung, Richard L. Sites, Mark T. Vandevoorde, William Edward Weihl
  • Method for identifying reasons for dynamic stall cycles during the execution of a program
    Patent number: 5857097
    Abstract: In a computerized method, performance data collected while a computer system executed instructions of a program are analyzed. The method collects performance data while executing the program. The performance data includes sample counts of instructions executed. The program is analyzed to determine classes of instructions. Instructions of the same equivalence class all execute the identical number of times. The execution frequencies for each instructions of each equivalence class is estimated. The estimated execution frequencies can then be used to determine the average number of cycles required to issue each instruction of each equivalence class. The average number of cycles can be compared with the minimum number of cycles to determine the number of dynamic stall cycles incurred by the instructions. Furthermore, reasons for the dynamic stall cycles can be inferred.
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: January 5, 1999
    Assignee: Digital Equipment Corporation
    Inventors: Monika Hildegard Henzinger, Shun-Tak Albert Leung, Richard L. Sites, Mark T. Vandevoorde, William Edward Weihl