Generation of Distributed Loop Control

We present a new methodology for controlling the space-time behavior of VLSI and FPGA-based processor arrays. The main idea is to generate simple local control elements which take control over the activeness of each attached processor element. Each control element thereby propagates a "start" and a "stop execution" signal to its neighbors. We show that our control mechanism is much more efficient than existing approaches because 1) only two control signals (start/stop) are required, 2) no extension of the computation space is necessary. 3) By the local propagation of just one start/stop signal, energy is saved as processing elements are only active between the time they have received the start signal and the time they have received the stop signal. Our methodology is applicable to one- and multi-dimensional processor arrays and is based on local control signal propagation. We provide a theoretical analysis of the overhead caused by the control structure.

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