Patents by Inventor David L. Detlefs

David L. Detlefs 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: 6173442
    Abstract: An object structure's header (40) allocates a two-bit synchronization-state field (42) solely to monitor data for implementing synchronization on that object. When the object is locked by a particular execution thread, or when one or more execution threads are waiting for a lock or notification on that object, its header contains a pointer to monitor resources in the form of a linked list of lock records (50, 52, 54) associated with the threads involved. The synchronization-state field (42) ordinarily contains an indication of whether such a linked list exists and, if so, whether its first member is associated with a thread that has a lock on the object. When a thread attempts to gain access to that linked list, it employs an atomic swap operation to place a special busy value in that lock-state field (42) and write its execution-environment pointer into the object's header (40).
    Type: Grant
    Filed: February 5, 1999
    Date of Patent: January 9, 2001
    Assignee: Sun Microsystems, Inc.
    Inventors: Ole Agesen, David L. Detlefs, Alex Garthwaite, Ross C. Knippel, Y. Srinivas Ramakrishna, Derek White
  • Patent number: 6161217
    Abstract: A computer system (10) is configured as a compiler to translate source code (FIG. 4) into object code (FIG. 6). The source code calls a polymorphic method on a receiver object. The compiler inlines the polymorphic method and guards the inlining with guard code that causes the executing microprocessor to skip the inlining in favor of a virtual method call when it determines that the inlined code is not appropriate for the receiver object. To make that determination, the guard code compares the address of the method version that has been inlined with the receiver object's pointer to its version of the polymorphic method.
    Type: Grant
    Filed: September 14, 1998
    Date of Patent: December 12, 2000
    Assignee: Sun Microsystems, Inc.
    Inventors: David L. Detlefs, Ole Agesen
  • Patent number: 6047125
    Abstract: In accordance with the present invention a method for modifying a sequence of instructions to improve memory management within a storage device during execution of the instructions, comprises the steps, performed by a processor, of (a) analyzing the sequence of instructions for a conflict indicating an undeterminable variable type, (b) determining the type of conflict, and (c) modifying the sequence of instructions to eliminate the conflict based on the determination.
    Type: Grant
    Filed: October 1, 1997
    Date of Patent: April 4, 2000
    Assignee: Sun Microsystems, Inc.
    Inventors: Ole Agesen, David L. Detlefs