Clustered Modulo Scheduling in a VLIW Architecture with Distributed Cache

Clustering is an approach that many microprocessors are adopting in recent times in order to mitigate the increasing penalties of wire delays. In this work we propose a novel clustered VLIW architecture which has all its resources partitioned among clusters, including the cache memory. A modulo scheduling scheme for this architecture is also proposed. This algorithm takes into account both register and memory inter-cluster communications so that the final schedule results in a cluster assignment that favors cluster locality in cache references and register accesses. It has been evaluated for both 2and 4-cluster configurations and for differing number and latencies of inter-cluster buses. The proposed algorithm produces schedules with very low communication requirements and outperforms previous cluster-oriented schedulers.