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:
Nov. 03, 1998
Filed:
Dec. 16, 1994
Gerrit Ary Slavenburg, Los Altos, CA (US);
Junien Labrousse, Palo Alto, CA (US);
U.S. Philips Corporation, New York, NY (US);
Abstract
A processing device performs operations in response to program instructions. In particular, values are written to a data memory of the system, which alters a defined visible state of the system. In the event of an exception (e.g. a pagefault or TLB miss in a virtual memory system), control returns to a recent checkpoint instruction after handling the exception, and instructions are re-executed. A record/replay circuit is provided in the form of an event memory, which remembers only those values read from the data memory since the last checkpoint. During the re-execution, the recorded values are reproduced instead of performing actual memory reads, and all memory accesses are suppressed. When the re-execution reaches the point where execution was originally interrupted, recording begins again to prepare for any further exception which may arise before the next checkpoint.