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:
Apr. 07, 1987
Filed:
Aug. 13, 1984
Marc A Auslander, Millwood, NY (US);
John Cocke, Bedford, NY (US);
Peter W Markstein, Yorktown Heights, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method for use during the optimizatin phase of an optimizing compiler for performing global common subexpression elimination and code motion which comprises: Determining the code `basis` for the object program which includes examining each basic block of code and determining the `basis` items on which each computation depends wherein `basis` items are defined as operands which are referenced in a basic block before being computed. The method next determines the 'kill set' for each `basis` item. Following this UEX, DEX, and THRU are determined for each basic block using the previously determined `basis` and 'kill set' information. AVAIL and INSERT are computed from UEX, DEX, and THRU, and appropriate code insertions are made at those locations indicated by the preceding step, and finally redundant code is removed using the AVAIL set.