Nonlinear Configurations for Superlinear Speedup by Supercompilation

It is a widely held belief that supercompilation like partial evaluation is only capable of linear-time program speedups. The purpose of this paper is to dispel this myth. We show that supercompilation is capable of superlinear speedups and demonstrate this with several examples. We analyze the transformation and identify the most-specific generalization (msg) as the source of the speedup. Based on our analysis, we propose a conservative extension to supercompilation using equality indices that extends the range of msg-based superlinear speedups. Among other benefits, the increased accuracy improves the time complexity of the palindrome-suffix problem from O(2 2 ) to O(n).