Compact generic intermediate representation (CGIR) to enable late binding in coarse grained reconfigurable architectures

In the era of platforms hosting multiple applications, where inter-application communication and concurrency patterns are arbitrary, static compile time decision making is neither optimal nor desirable. As a part of solving this problem, we present a novel method for compactly representing multiple configuration bitstreams of a single application, with varying parallelisms, as a unique, compact, and customizable representation, called CGIR. The representation thus stored is unraveled at runtime to configure the device with optimal (e.g. in terms of energy) implementation. Our goal was to provide optimal decision making capability to the runtime resource manager (RTM) without compromising the runtime behavior or the memory requirements of the system. The presence of multiple binaries enhance optimality by providing the RTM with multiple implementations to choose from. The CGIR ensures minimal increase in memory requirements with the addition of each binary. The low-cost unraveling of CGIR guarantees the runtime behavior. We have chosen the dynamically reconfigurable resource array (DRRA) as a vehicle to study the feasibility of our approach. Simulation results using 16 point decimation in time fast Fourier transform (FFT) has showed massive (up to 18% for 2 versions, 33% for 3 versions) memory savings compared to state of the art. Formal evaluation shows that the savings increase with the increase in the number of implementations stored.