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:
Mar. 05, 2002
Filed:
Feb. 08, 1999
Andrew E. Ayers, Amherst, NH (US);
Anant Agarwal, Weston, MA (US);
Richard Schooler, Cambridge, MA (US);
Incert Software Corporation, Cambridge, MA (US);
Abstract
A method of back-tracing execution of a computer program, where the computer program comprises a plurality of blocks, comprises instrumenting an original version of the program by adding instrumentation code to some or all of the blocks to form an instrumented program. Instrumentation can be added at the binary or source level, or at link time. The instrumentation code records execution sequence information upon execution of the corresponding instrumented block to create a trace record of the executed program. The execution sequence information for each block comprises a block identifier which identifies the corresponding block. A detailed back-trace is generated, after the program has executed, by replacing each recorded block identifier with program counters associated with each instruction in the corresponding block. The application may comprise several programs or subprograms, in which case separate regions of memory can be maintained. Each region is associated with a program or subprogram or a set of programs or subprograms and stores therein part of the trace record corresponding to the associated set of programs or subprograms. The trace records themselves may be of different types. After execution, the trace record is presented to a user, in the form of assembly code, or more preferably, in the form of source level code. In an alternative embodiment, a summary of the trace record recorded during execution of an instrumented program is presented to a user. Various types of traces can be produced, including a last instruction trace and a first instruction trace.