1. A scheduling method for a multiprocessor for scheduling an order of assignment of execution units processed in parallel and subject to scheduling to a plurality of processors, comprising: sequentially retrieving at least one group, each including execution units subject to scheduling, from a ready queue, the ready queue storing groups in a ready state; referring to a schedule table which holds the execution units in relation to the plurality of processors to which the execution units are assigned; setting up flags for the plurality of processors to which the execution units are assigned, when the execution units belonging to the group retrieved from the ready queue are listed in the schedule table; appending the retrieved group to an assignment list storing groups that are candidates for assignment to respective processors of the plurality of processors, when the execution units belonging to the retrieved group are not listed in the schedule table and when all execution units belonging to the retrieved group are assignable to the respective processors at the same time; assigning all execution units belonging to the retrieved group stored in the assignment list to the respective processors for which flags are not set up in the schedule table; and mapping processor resources, exclusively used by each of the execution units belonging to the retrieved group, to an address space referred to by the execution units so that the execution units can refer to each other's processor resources; wherein the execution units belonging to the retrieved group are assignable to the respective processors at the same time include a first execution unit and a second execution unit, and allowing the first execution unit to write data in a resource area for the second execution unit mapped to the address space.