The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 15, 2009
Filed:
Aug. 23, 2005
Shailender Chaudhry, San Francisco, CA (US);
Paul Caprioli, Mountain View, CA (US);
Sherman H. Yip, San Francisco, CA (US);
Guarav Garg, Sunnyvale, CA (US);
Ketaki Rao, San Francisco, CA (US);
Shailender Chaudhry, San Francisco, CA (US);
Paul Caprioli, Mountain View, CA (US);
Sherman H. Yip, San Francisco, CA (US);
Guarav Garg, Sunnyvale, CA (US);
Ketaki Rao, San Francisco, CA (US);
Sun Microsystems, Inc., Santa Clara, CA (US);
Abstract
One embodiment of the present invention provides a system which avoids a live-lock state in a processor that supports speculative-execution. The system starts by issuing instructions for execution in program order during execution of a program in a normal-execution mode. Upon encountering a launch condition during the execution of an instruction (a 'launch instruction') which causes the processor to enter a speculative-execution mode, the system checks status indicators associated with a forward progress buffer. If the status indicators indicate that the forward progress buffer contains data for the launch instruction, the system resumes normal-execution mode. Upon resumption of normal-execution mode, the system retrieves the data from a data field contained in the forward progress buffer and executes the launch instruction using the retrieved data as input data for the launch instruction. The system next deasserts the status indicators. The system then continues to issue instructions for execution in program order in normal-execution mode. Using the forward progress buffer in this way prevents the processor from entering a potential live-lock state.