Abstract: Program execution can be monitored and recorded for later playback. Certain state changes that can be predicted via a virtual processor during playback need not be recorded, so a compressed recording can be stored. To facilitate random access with respect to time during playback, key frames can be stored within the compressed recording. An index mechanism can associate key frames with particular memory addresses. Additionally, a snapshot of values for memory addresses can be used to further facilitate determining the value of a memory address without having to simulate execution. Multiprocessor executions can be supported, and playback can be done on a machine type different from that on which recording took place.

Abstract: A compiler method is adapted to be executed by a computer with limited memory, yet enables cross-CU optimization during the conversion of a source code listing to an object code listing. The compiler method includes the steps of: converting plural source code listings into plural CUs, each CU being an intermediate code representation; analyzing each CU and deriving a global CU table which includes a reference to each analyzed CU; a program symbol table which indicates in which CU each program routine is defined and/or referred to; and a global call graph which notes each routine in each CU, indicates references therebetween, and further indicates where the routine exists in the program symbol table. The method further derives a CU symbol table which includes information that includes a reference for each routine defined in a CU to the intermediate representation for that routine.