URPR—An extension of URCR for software pipelining

Abstract

The software pipeline technique is an effective approach to optimizing loops in array processor programs, but existing methods are of high complexity and the results may not be satisfactory. This paper introduces the URPR algorithm, an extension of the microcode loop compaction algorithm URCR. Firstly, unroll the loop(the number of unrolled loop bodies relies on the inter-body data dependency); secondly, pipeline the unrolled loop bodies one by one; and finally, a new optimized loop body is obtained after rerolling. Preliminary tests indicate that URPR produces favorable results with lower complexity.