A systematic approach to the design of modular systolic arrays

The data dependence method is extended to the design of systolic arrays that are not regular but can be thought of as a combination of basic regular systolic modules. For problems that have an intrinsic modular structure, a strategy based on decomposition into subproblems for which a systolic design can be easily derived is suggested. Thus the major problem of the synthesis procedure becomes that of interconnecting the basic modules according to the timing and data-flow constraints that arise from the decomposition of the original problem. The synthesis procedure consists of two steps. The local time and space function is derived for the basic module using standard methodologies, and the global time function is then obtained by imposing additional constraints on the flow of the variables and used to derive the interconnections between the modules. The approach is illustrated on two different problems: 2-D convolution and the shortest path on a layered graph.<>