Automatic Parallelization of Side-Effecting Higher-Order Scheme Programs

The multi-core revolution heralds a challenging era for software maintainers. Manually parallelizing large sequential code bases is often infeasible. In this paper, we present a program transformation that automatically parallelizes real-life Scheme programs. The transformation has to be instantiated with an interprocedural dependence analysis that exposes parallelization opportunities in a sequential program. To this end, we extended a state-of-the art analysis that copes with higher-order procedures and side effects. Our parallelizing transformation exploits all opportunities for parallelization that are exposed by the dependence analysis. Experiments demonstrate that this brute-force approach realizes scalable speedups in certain benchmarks, while others would benefit from a more selective parallelization.