Techniques for LI-BDN synthesis for hybrid microarchitectural simulation

Computer designers rely upon near-cycle-accurate microarchitectural simulation to explore the design space of new systems. Unfortunately, such simulators are becoming increasingly slow as systems become more complex. Hybrid simulators which offload some of the simulation work onto FPGAs can increase the speed; however, such simulators must be automatically synthesized or the time to design them becomes prohibitive. Furthermore, FPGA implementations of simulators may require multiple FPGA clock cycles to implement behavior that takes place within one simulated clock cycle, making correct arbitrary composition of simulator components impossible and limiting the amount of hardware concurrency which can be achieved. Latency-Insensitive Bounded Dataflow Networks (LI-BDNs) have been suggested as a means to permit composition of simulator components in FPGAs. However, previous work has required that LI-BDNs be created manually. This paper introduces techniques for automated synthesis of LI-BDNs from the processes of a System-C microarchitectural model. We demonstrate that LI-BDNs can be successfully synthesized. We also introduce a technique for reducing the overhead of LI-BDNs when the latency-insensitive property is unnecessary, resulting in up to a 60% reduction in FPGA resource requirements.