Patent ID: 7467376
Filing Date: 2008-12-16
Classification: G06F

Abstract:
1. A method for compressing a program code which comprises a plurality of code instructions to be executed by an interpreter, some of the said instructions handling objects, each object possessing a value, said method comprising: a first step in which a semantic analysis of the program code is performed, which returns a list of objects accessed at each point of the program code, a second step of identifying by means of information which has been computed by semantic analysis in the first step, for any object handled by the program code, occurrences of various instruction groups in the program code which operate on this object and for which a specific register is made available in an instruction set of the interpreter, a third step in which number of occurrences of each of the said objects is compared to a threshold value, and for each object such that this number of occurrences is greater than this threshold value, a fourth step in which, at a program point which in each possible execution of the program code, precedes execution of one occurrence of instruction groups associated with the said object, one introduces a code performing an assignment of a value of said object to one of the special registers of the interpreter, a fifth step in which one replaces the instruction groups at each occurrence in the program code by specialized instructions in relation to the said register corresponding to them, a sixth step in which one eliminates from the program code instructions and the constructions which have become useless or redundant after the fifth step.