1. A task distribution program, which converts a source program for a single processor into a program for a multiprocessor device having a plurality of processors, wherein the task distribution program causing a computer to construct a task distribution unit for, by referencing a definition file, which is stored in memory, and which associates one of the processors of the multiprocessor device with tasks of the source program, converting the source program into a distributed source program in which the plurality of tasks of the source program are distributed among the plurality of processors, and adding, as an argument, to the distributed tasks a processor ID of a task subject to processing by the distributed task.