STACK MACHINE WITH IMPROVED CACHE MEMORY FOR VARIABLES

The present invention discloses a data processing system having a program structure and execution mode where an actual argument is bound to a formal argument of a function to be called by storing a pair of a variable name as the formal argument and a variable as the actual argument into a First-In-Last-Out type stack memory which is an environment list, the function called executes processings using a latest bind value of said environment list when referring to variable values, when a value of such function is obtained, the function value is returned by deleting the formal argument variable of the function from the environment list. The system includes an associative buffer memory provided externally to the stack memory, where at least the variable name and location data of variable on the environment list are stored in the associative buffer memory, and thereby the access time for referring to variables stored in the stack memory can be curtailed.