DynTile: Parametric tiled loop generation for parallel execution on multicore processors

Abstract

Loop tiling is an important compiler transformation used for enhancing data locality and exploiting coarse-grained parallelism. Tiled codes in which tile sizes are runtime parameters - called parametrically-tiled codes - are important for empirical tuning systems like ATLAS. Some recent work has addressed the problem of generating sequential parametric tiled code. In this paper we describe DynTile, a system for transforming untiled sequential input C code containing affine imperfectly nested loops to parametrically tiled code for parallel execution on multicore processors. The effectiveness of the system is demonstrated using a number of benchmarks on an eight-core system.