He has published numerous papers and given many presentations on computational complexity, parallel algorithms, parallel architectures, interconnection networks, parallel languages and libraries and parallel programming environments.

Marc is AAAS Fellow, ACM Fellow and IEEE Fellow. He has Erdos number 2 and is a mathematical descendant of Jacques Salomon Hadamard. He won the IEEE Award for Excellence in Scalable Computing and the IEEE Seymour Cray Computer Engineering Award.

His research focuses on high-performance computing, with recent work on programming models, tools, and performance analysis. The work on programming models studies methods of supporting a global name space and supporting data caching, while allowing for user control of communication and avoiding the high cost of coherence protocols. The work on tools studies refactoring tools for performance tuning. The work on performance analysis is directed at improving the scalability of climate codes.