Patent ID: 6279149
Filing Date: 2001-08-21
Classification: G06F

Abstract:
A program storage device readable by a machine, tangibly embodying a series of instructions executable by the machine to perform method steps for analyzing a computer program comprising a plurality of aggregate variables and a plurality of statements and generating data that characterizes use of said variables, said method steps comprising:(i) for every aggregate variable in the program, initializing data associated with the said variable to refer to a range of locations that the said aggregate variable denotes;(ii) for every reference in the program to a subset of the locations denoted by an aggregate variable, modifying the data associated with the said variable by adding breakpoints corresponding to the endpoints of the range of locations that the said reference denotes; and(iii) for at least one statement that copies the contents of a range R1 of locations of an aggregate variable V1 to a range R2 of locations of an aggregate variable V2,(a) identifying the breakpoints in the range R1 from the data associated with variable V1, and modifying the data associated with variable V2 to add breakpoints at corresponding locations within range R2, and(b) identifying the breakpoints in the range R2 from the data associated with variable V2, and modifying the data associated with variable V1 to add breakpoints at corresponding locations within range R1.