Fast argument load in a reconfigurable data processor

A reconfigurable processor includes an array of configurable units connected by a bus system. Each configurable unit has a configuration data store, organized as a shift register, to store configuration data. The configuration data store also includes individually addressable argument registers respectively made up of word-sized portions of the shift register to provide arguments to the configurable unit. The configurable unit also includes program load logic shift data into the configuration data store, and argument load logic to directly load data into the argument registers without shifting the received argument data through the shift register. A program load controller is associated with the array to respond to a program load command by executing a program load process, and a fast argument load (FAL) controller is associated with the array to respond to an FAL command by executing an FAL process.