To be capable of concurrent execution of a function group not in data conflict by a plurality of cores and to execute a function pair in data conflict in a temporal separation manner. A process barrier 20 includes N−1 checker functions 22 and one limiter function 23, where the number of cores capable of concurrently executing the functions is N (N is an integer equal to or greater than 2), the checker functions 22 determine whether the head entry of a lock-free function queue LFQ1 is either the checker function 22 or the limiter function 23, and repeats reading of the head entry of the lock-free function queue LFQ1 if either, and ends processing if neither, and the limiter function 23 is an empty function ending without performing any processing.