A Faster Algorithm for Enumerating Connected Convex Subgraphs in Acyclic Digraphs

Subgraph enumeration is one of the most crucial steps involved in the custom instruction identification for application-specific instruction set processors. Generating all connected convex subgraphs from an acyclic digraph is a computationally difficult problem. In this letter, we propose a simple and fast algorithm for enumerating all connected convex subgraphs in acyclic digraphs. Experimental results show that our algorithm outperforms the latest algorithm in the literature. We also present a parallel approach for enumerating all connected convex subgraphs using MapReduce. Results for real world benchmarks covering different application domains reveal that the parallel approach can achieve near linear speedup over the sequential approach.