Patents by Inventor Alexander J. Starr

Alexander J. Starr 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).

  • Patent number: 6922773
    Abstract: For use in a data processor comprising an instruction execution pipeline comprising N processing stages, a system and method of encoding constant operands is disclosed. The system comprises a constant generator unit that is capable of generating both short constant operands and long constant operands. The constant generator unit extracts the bits of a short constant operand from an instruction syllable and right justifies the bits in an output syllable. For long constant operands, the constant generator unit extracts K low order bits from an instruction syllable and T high order bits from an extension syllable. The right justified K low order bits and the T high order bits are combined to represent the long constant operand in one output syllable. In response to the status of op code bits located within a constant generation instruction, the constant generator unit enables and disables multiplexers to automatically generate the appropriate short or long constant operand.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: July 26, 2005
    Assignees: STMicroelectronics, Inc., Hewlett-Packard Company
    Inventors: Paolo Faraboschi, Alexander J. Starr, Anthony X. Jarvis, Geoffrey M. Brown, Mark Owen Homewood, Gary L. Vondran
  • Patent number: 6829700
    Abstract: There is disclosed a data processor comprising: 1) an instruction execution pipeline comprising N processing stages for executing a load instruction; 2) a status register for storing a modifiable configuration value, the modifiable configuration value having a first value indicating the data processor is capable of executing a misaligned access handling routine and a second value indicating the data processor is not capable of executing a misaligned access handling routine; 3) a misalignment detection circuit for determining if the load instruction performs a misaligned access to a target address of the load instruction and, in response to a determination that the load instruction does perform a misaligned access, generating a misalignment flag; and 4) exception control circuitry capable of detecting the misalignment flag and in response thereto determining if the modifiable configuration value is equal to the first value.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: December 7, 2004
    Assignees: STMicroelectronics, Inc., Hewlett-Packard Company
    Inventors: Paolo Faraboschi, Alexander J. Starr, Geoffrey M. Brown, Mark Owen Homewood
  • Patent number: 6807628
    Abstract: There is disclosed a data processor having a clustered architecture that comprises a plurality of clusters and an interrupt and exception controller. Each of the clusters comprises an instruction execution pipeline having N processing stages. Each of the N processing stages is capable of performing at least one of a plurality of execution steps associated with instructions being executed by the clusters. The interrupt and exception controller operates to (i) detect an exception condition associated with one of the executing instructions, wherein this executing instruction issued at time t0, and (ii) generate an exception in response to the exception condition upon completed execution of earlier ones of the executing instructions, these earlier executing instructions issued at time preceding t0.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: October 19, 2004
    Assignee: STMicroelectronics, Inc.
    Inventors: Mark Owen Homewood, Anthony X. Jarvis, Alexander J. Starr
  • Patent number: 6691210
    Abstract: A cache flush controller, and an associated method, selectably flushes a memory cache of a data processor. The cache flush controller operates at a memory bus level of the data processor and operates to flush a selected line, or lines of the memory cache by writing arbitrary, selected values to the selected line or lines of the memory cache.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: February 10, 2004
    Assignees: STMicroelectronics, Inc., Hewlett-Packard Development Company L.P.
    Inventors: Paolo Faraboschi, Alexander J. Starr, Geoffrey M. Brown, Richard L. Ford
  • Publication number: 20020124163
    Abstract: There is disclosed a data processor having a clustered architecture that comprises a plurality of clusters and an interrupt and exception controller. Each of the clusters comprises an instruction execution pipeline having N processing stages. Each of the N processing stages is capable of performing at least one of a plurality of execution steps associated with instructions being executed by the clusters. The interrupt and exception controller operates to (i) detect an exception condition associated with one of the executing instructions, wherein this executing instruction issued at time t1, and (ii) generate an exception in response to the exception condition upon completed execution of earlier ones of the executing instructions, these earlier executing instructions issued at time preceding t0.
    Type: Application
    Filed: December 29, 2000
    Publication date: September 5, 2002
    Inventors: Mark Owen Homewood, Anthony X. Jarvis, Alexander J. Starr
  • Publication number: 20020087799
    Abstract: A cache flush controller, and an associated method, selectably flushes a memory cache of a data processor. The cache flush controller operates at a memory bus level of the data processor and operates to flush a selected line, or lines of the memory cache by writing arbitrary, selected values to the selected line or lines of the memory cache.
    Type: Application
    Filed: December 29, 2000
    Publication date: July 4, 2002
    Inventors: Paolo Faraboschi, Alexander J. Starr, Geoffrey M. Brown, Richard L. Ford
  • Publication number: 20020087841
    Abstract: There is disclosed a data processor comprising: 1) an instruction execution pipeline comprising N processing stages for executing a load instruction; 2) a status register for storing a modifiable configuration value, the modifiable configuration value having a first value indicating the data processor is capable of executing a misaligned access handling routine and a second value indicating the data processor is not capable of executing a misaligned access handling routine; 3) a misalignment detection circuit for determining if the load instruction performs a misaligned access to a target address of the load instruction and, in response to a determination that the load instruction does perform a misaligned access, generating a misalignment flag; and 4) exception control circuitry capable of detecting the misalignment flag and in response thereto determining if the modifiable configuration value is equal to the first value.
    Type: Application
    Filed: December 29, 2000
    Publication date: July 4, 2002
    Inventors: Paolo Faraboschi, Alexander J. Starr, Geoffrey M. Brown, Mark Owen Homewood
  • Publication number: 20020087834
    Abstract: For use in a data processor comprising an instruction execution pipeline comprising N processing stages, a system and method of encoding constant operands is disclosed. The system comprises a constant generator unit that is capable of generating both short constant operands and long constant operands. The constant generator unit extracts the bits of a short constant operand from an instruction syllable and right justifies the bits in an output syllable. For long constant operands, the constant generator unit extracts K low order bits from an instruction syllable and T high order bits from an extension syllable. The right justified K low order bits and the T high order bits are combined to represent the long constant operand in one output syllable. In response to the status of op code bits located within a constant generation instruction, the constant generator unit enables and disables multiplexers to automatically generate the appropriate short or long constant operand.
    Type: Application
    Filed: December 29, 2000
    Publication date: July 4, 2002
    Applicant: STMicroelectronics, Inc.
    Inventors: Paolo Faraboschi, Alexander J. Starr, Anthony X. Jarvis, Geoffrey M. Brown, Mark Owen Homewood, Gary L. Vondran