Using the Meeting Graph Framework to Minimise Kernel Loop Unrolling for Scheduled Loops

This paper improves our previous research effort [1] by providing an efficient method for kernel loop unrolling minimisation in the case of already scheduled loops, where circular lifetime intervals are known. When loops are software pipelined, the number of values simultaneously alive becomes exactly known giving better opportunities for kernel loop unrolling. Furthermore, fixing circular lifetime intervals allows us to reduce the algorithmic complexity of our method compared to [1] by computing a new research space for minimal kernel loop unrolling. The meeting graph (MG) [3] is one of the frameworks proposed in the literature which models loop unrolling and register allocation together in a common formal framework for software pipelined loops. Although MG significantly improves loop register allocation, the computed loop unrolling may lead to unpractical code growth. This work proposes to minimise the loop unrolling degree in the meeting graph by making an adaptation of the approa...

• Type: Conference
• Year: 2009
• Where: LCPC
• Authors: Mounira Bachir, David Gregg, Sid Ahmed Ali Touati
• Keywords: Kernel Loop, LCPC 2009, Loop Unrolling, Loop Unrolling Minimisation, System Software