Common formula deleting method

Abstract

Abstract PURPOSE:To improve both the production and execution efficiencies of objects by using an analysis tree to delete a common formula when a syntax structure is analyzed with a C language compiler. CONSTITUTION:An address calculation formula or a character addition formula is first decided according to the types of operators by evaluating the members forming an analysis tree in the analyzing order. Then it is decided whether the present member should be processed or not. If so, it is checked whether a common formula is equal or not to a member listed on a candidate table. If not, the next scan is carried out. If the common formula is not equal to said member, this formula is registered into the candidate table. While it is decided whether a partial tree rooted from the present item is equal or not to a partial tree set on the table in case the common formula is equal to said member. If so, the table is registered into a common formula table. If not, the next scan is carried out. In such a way, the scan or non-scan is decided with all members. If the scans are not finished, the next member is extracted. While the pattern is changed into that of the deleted analysis tree of the common formula based on the common formula table if said scans are through.

Inventors

• 👤 Hiroshi Nakada
• 👤 Fumiko Baba

Bibliographic Details