Register Allocation for Software Pipelining with Predication using Spiral Graph

In this paper authors present Predicated Spiral Graph and Predicated Short Bridge Algorithm, that allocate registers to software pipelined loops with predication under the rotating register architectures. When using predication to execute the conditional branches, two separate variables in the pipelined kernel may share one real register, even if these overlap. Authors extend Spiral Graph to multiplexed style, and present five strategies of sharing a real register by the overlapped variables. The register allocation experiments using pseudo loop programs shows that the strategies are effective on sharing.