1. A simulation method of instruction scheduling, comprising: detecting a loop from an instruction sequence to be simulated; registering an instruction scheduling target instruction sequence in a loop detection state; comparing a current scheduling target instruction sequence with the registered scheduling target instruction sequence for each loop cycle; and skipping, when the current scheduling target instruction sequence matches the registered scheduling target instruction sequence, scheduling of that scheduling target instruction sequence, and newly registering, when the two instruction sequences do not match, the current scheduling target instruction sequence and executing scheduling.