Soft scheduling in high level synthesis

In this paper, we establish a theoretical framework for a new concept of scheduling called soft scheduling. In contrasts to the traditional schedulers referred as hard schedulers, soft schedulers make soft decisions at a time, or decisions that can be adjusted later. Soft scheduling has a potential to alleviate the phase coupling problem that has plagued traditional high level synthesis (HLS), HLS for deep submicron design and VLIW code generation. We then develop a specific soft scheduling formulation, called threaded schedule, under which a linear, optimal (in the sense of online optimality) algorithm is guaranteed.