This application discloses a computing system to identify portions of source code in a test bench that correspond to class objects, and insert handle tracking code at locations in the test bench associated with the identified portions of source code. During simulation of the test bench, the computing system can execute the handle tracking code, which generates handle occupancies corresponding to memory pointers associated with the class objects. Each of the handle occupancies can include a handle reference or memory pointer for a class object, a location in the test bench corresponding to usage of the memory pointer, and a simulation time associated with the generation of the handle occupancy. The computing system can arrange the handle occupancies, synchronize the handle occupancies to portions of source code in the test bench, and display the handle occupancies and the test bench source code in a debug window.