Patent ID: 7458071
Filing Date: 2008-11-25
Classification: G06F

Abstract:
1. A compilation method for converting a source program written in a high-level language into object codes, comprising: generating intermediate codes from the source program; optimizing the intermediate codes by converting a pass-by-value argument into a pass-by-reference argument, in the case where both of the following conditions are satisfied: there is no procedure that may indirectly call a procedure with pass-by-value argument; and the pass-by-value argument is not updated within a definition according to the procedure with pass-by-value argument; and converting the optimized intermediate codes into object codes, wherein the optimizing further includes: extracting pass-by-value argument update information based on the intermediate codes, the information including at least the following: a procedure with pass-by-value argument; a procedure that directly calls the procedure with pass-by-value argument; a procedure that may indirectly call the procedure with pass-by-value argument; a pass-by-value argument of the procedure with pass-by-value argument; and update judgment information indicating whether or not the pass-by-value argument is updated within the definition according to the procedure with pass-by-value argument; and converting the procedure that calls a procedure with pass-by-value argument into the procedure that calls a procedure with pass-by-reference, in the case where the pass-by-value argument update information indicates that there is no procedure that may indirectly call a procedure with pass-by-value argument, and the pass-by-value argument is not updated within the definition according to the procedure with pass-by-value argument.