A method of pipeline processing that attends to computation by connecting a central processing unit to an additional computation unit, comprising the steps of: storing a computation instruction supplied to the computation unit; executing the stored computation instruction, and checking if completing the execution of the computation instruction requires more than a predetermined time length; shifting the stored computation instruction to a dedicated storage if completing the execution of the computation instruction requires more than the predetermined time length; and executing the computation instruction stored in the dedicated storage until the execution of the computation instruction is completed.