Discovering Pipeline Parallel Patterns in Sequential Legacy C++ Codes

Abstract

Since free performance lunch of processors is over, parallelism has become the new trend in hardware and architecture design. However, parallel resources deployed in data centers are underused in many cases, given that sequential programming is still deeply rooted in current software development. To face this problem, new methodologies and techniques for parallel programming have been progressively developed. For instance, parallel frameworks offer programming skeletons that allow expressing parallelism and concurrency in applications to better exploit concurrent hardware. Nevertheless, it remains a large portion of production software, coming from a broad range of scientific and industrial areas, that still execute sequential legacy codes. Taking into account that these software modules contain thousands, or even millions, of code lines, the effort needed to identify parallel regions is extremely high. To pave the way in this area, this paper presents Parallel Pattern Analyzer Tool (PPAT), a software component that aids discovering and annotating parallel patterns in source codes. Hence, facilitating the transformation of sequential code into parallel. We evaluate this tool for the special case of parallel pipelines using a series of well-known sequential benchmark suites.