Type-Inference Based Short Cut Deforestation (Nearly) without Inlining

Deforestation optimises a functional program by transforming it into another one that does not create certain intermediate data structures. Our type-inference based deforestation algorithm performs extensive inlining, but only limited inlining across module boundaries is practically feasible. Therefore we here present a type-inference based algorithm that splits a function denition into a worker denition and a wrapper denition. For deforestation we only need to inline the small wrappers which transfer the required information. We show that we even can deforest denitions of functions that consume their own result with the worker/wrapper scheme, in contrast to the original algorithm with inlining.