Use of stack depth to identify machine code mistakes
Patent 5450575 Issued on September 12, 1995. Estimated Expiration Date: 
September 12, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
September 12, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesReal-time tracing of dynamic local data in high level languages in the presence of process context switches Assembly language programming potential error detection scheme sensing apparent inconsistency with a previous operation Patent #: 5132972 InventorAssigneeApplicationNo. 666210 filed on 03/07/1991US Classes:717/128, Tracing714/38, Of computer software717/132, Using program flow graph717/144Including graph or tree representation (e.g., abstract syntax tree or AST)ExaminersPrimary: Baker, Stephen M.Attorney, Agent or FirmForeign Patent References
International ClassesG06F 011/00G06F 009/45 AbstractA code translator, constructed similar to a compiler, accepts as an input to be translated the assembly code written for one architecture (e.g., VAX), and produces as an output object code for a different machine architecture (e.g., RISC). The input code is converted into an intermediate language, and a flow graph is constructed. The flow graph is referenced by a flow analyzer for recognizing certain architecture-specific and calling standard-specific coding practices or idioms that can produce mistakes if not revised before converting, particularly relating to stack usage. By tracking stack usage within and across routines, the compiler can distinguish up-level stack and return address references from valid local references. Also, it can inform the user of stack misalignment, which has a severe performance penalty, and can detect code segments where different flow paths may result in different stack depths at runtime, which may indicate a source code error.Other References
| |
