Patents by Inventor Douglas M. Priest

Douglas M. Priest 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: 6675292
    Abstract: A method, apparatus, and computer program product for handling IEEE 754 standard exceptions for Single Instruction Multiple Data (SIMD) instructions. Each SIMD sub-operation's corresponding IEEE 754 exception flag is bit-wise “ORed” with an accrued exception field if a trap enable mask field is configured to mask the exception, with the “ORed” result written back in the accrued exception field. If the trap enable mask field is configured to enable the exception, the accrued exception field and a current exception field are cleared, and an unfinished floating-point exception flag is set in a floating-point trap type field. The actual sub-operation(s) causing the exception is determined through software.
    Type: Grant
    Filed: August 13, 1999
    Date of Patent: January 6, 2004
    Assignee: Sun Microsystems, Inc.
    Inventors: J. Arjun Prabhu, Douglas M. Priest
  • Publication number: 20030028759
    Abstract: A method, apparatus, and computer program product for handling IEEE 754 standard exceptions for Single Instruction Multiple Data (SIMD) operations. Each SIMD sub-instruction's corresponding IEEE 754 exception flag is bit-wise “ORed” with an accrued exception field if a trap enable mask field is configured to mask the exception, with the “ORed” result written back in the accrued exception field. If the trap enable mask field is configured to enable the exception, the accrued exception field and a current exception field are cleared, and an unfinished floating-point exception flag is set in a floating-point trap type field. The actual sub-instruction(s) causing the exception is determined through software.
    Type: Application
    Filed: August 13, 1999
    Publication date: February 6, 2003
    Inventors: J. ARJUN PRABHU, DOUGLAS M. PRIEST
  • Patent number: 6427160
    Abstract: In a computer system, a method and system for verifying whether a floating-point logic unit correctly directly rounds floating-point numbers when conducting multiplication, square root, and division operations. A bit sequence that represents a directed boundary condition for a mathematical operation is identified. This sequence is then recast in terms of a series of integer equations. A recurrence is used to solve these equations to produce difficult test data. When solving the equations, any intermediate terms that exceed the computer's precision are discarded. The logic then conducts the mathematical operation under inspection using the test cases. The logic's computed value is then compared to an expected value. If the computed value equals the expected value, the logic has accurately performed the operation. If not, the logic is faulty.
    Type: Grant
    Filed: August 10, 1999
    Date of Patent: July 30, 2002
    Assignee: Sun Microsystems, Inc.
    Inventors: Michael Parks, Douglas M. Priest