Computer method and apparatus for analyzing program instructions executing in a computer system

摘要

In a computerized method, performance data collected while a computer system executed instructions of a program are analyzed. The method collects performance data while executing the program. The performance data includes sample counts of instructions executed. The program is analyzed to determine classes of instructions. Instructions of the same equivalence class all execute the identical number of times. The execution frequencies for each instructions of each equivalence class is estimated. The estimated execution frequencies can then be used to determine the average number of cycles required to issue each instruction of each equivalence class. The average number of cycles can be compared with the minimum number of cycles to determine the number of dynamic stall cycles incurred by the instructions. Furthermore, reasons for the dynamic stall cycles can be inferred.