SETTING INSTANCE BREAKPOINTS IN OBJECT ORIENTED COMPUTER PROGRAMS

摘要

A mechanism for setting a conditional breakpoint on all methods called by a specific instance of a class. To set the instance breakpoint, the debugger must first determine all of the methods that can be applied to the object type or class. In an environment in which full debuggi ng information includes the correspondence between virtual function tables and specific classes, and full class hierarchy information, the methods can be located by locating the pointer to the type' s virtual function table, and from the virtual function table, locating the specific class in the debuggin g information. Identifying the specific type permits all of the base classes of the type to be identifi ed in the debugging information, and from the class hierarchy information, all methods for objec ts of the type can be compiled. The debugger then sets a conditional breakpoint on each method, th e condition specifying that the breakpoint should cause program execution to automatically stop onl y if the method is being called for the particular object or instance for which the instance breakpoi nt was set. Information gathered at these program suspensions can be used in granular program debugg ing to locate problems particular to the specific instance.