PURPOSE: To accurately exactly evaluate which part in a speed performance evaluation object program requires long time.

CONSTITUTION: In the case of simulation with a simulation engine 101, instructions are held in program counters 101c and 101d. Then, the number of times of instruction execution and the accumulated number of clocks required for the execution are arranged for each instruction and respectively stored in an execution time number storage arrangement 102b and an accumulated clock number storage arrangement 102c. Therefore, the number of times of execution of the same instruction and the accumulated time required for that execution can be calculated. Since any function for extracting start time or end time for each instruction or any sampling program to be cyclically interrupted is not required, the accuracy of speed performance evaluation is not limited by overhead corresponding to these function and sampling program. Further, even concerning the instruction to be repeatedly executed in a loop, the executing time required for that execution can be recognized.