B2Sim:

Abstract

State-of-the-art architectural simulators support cycle accurate pipeline execution of application programs. However, it takes days and weeks to complete the simulation of even a moderate- size program. During the execution of a program, program behavior does not change randomly but changes over time in a predictable/periodic manner. This behavior provides the opportunity to limit the use of a pipeline simulator. More precisely, this paper presents a hybrid simulation engine, named B2Sim for (cycle-characterized) Basic Block based Simulator, where a fast cache simulator e.g., sim-cache and a slow pipeline simulator e.g., sim-outorder are employed together. B2Sim reduces the runtime of architectural simulation engines by making use of the instruction behavior within executed basic blocks. We have integrated B2Sim into SimpleScalar and have achieved on average a factor of 3.3 times speedup on the SPEC2000 benchmark and Media-bench programs compared to conventional pipeline simulator while maintaining the accuracy of the simulation results with less than 1% CPI error on average.