Paraforming:Forming Parallel Haskell Programs Using Novel Refactoring Techniques

Enabling programmers to "think parallel'' is critical if we are to be able to effectively exploit future multicore/manycore architectures.This paper introduces paraforming: a new approach to constructing parallel functional programs using formally-defined refactoring transformations.We introduce a number of new refactorings for Parallel Haskell that capture common parallel abstractions, such as divide-and-conquerand data parallelism,and show how these can be used by the HaRe Haskell refactoring engine. Using a paraforming approach, we are able to easily obtainsignificant and scalable speedups (up to 7.8 on an 8-core machine)