1. A method for controlling the execution of a computer program, having multitasking capability, on a computing element of a controller for at least one of controlling and regulating a system that can take up various possible system states, comprising: performing the following operations with the computing element of the controller: subdividing the computer program into a plurality of functionally linked functionalities; defining possible operating states for the functionalities; defining possible system states of the system; allocating specifiable operating states to the functionalities for each system state; ascertaining dependencies of the functionalities on one another, a first functionality being dependent upon a second functionality if at least one input variable of the first functionality is ascertained in the second functionality; and centrally specifying the operating states required for a certain system state, taking into consideration the ascertained dependencies among the functionalities and further boundary conditions, wherein each of the operating states is defined by an operating state variable which is able to take up various operating state values, and wherein each of the operating state variables is able to take up operating state values corresponding to “full functionality”, “limited functionality” and “no functionality” settings.