ADL-based specification of implementation styles for functional simulators

Functional simulators find widespread use as sub-systems within microarchitectural simulators. The speed of functional simulators is strongly influenced by the implementation style of the functional simulator, e.g. interpreted vs. binary-translated simulation. Speed is also strongly influenced by the level of detail of the interface the functional simulator presents to the rest of the timing simulator. This level of detail may change during design space exploration, requiring corresponding changes to the interface and the simulator. However, for many implementation styles, changing the interface is difficult. As a result, architects may choose either implementation styles which are more malleable or interfaces with more detail than is necessary. In either case, simulation speed is traded for simulator design time. We show that this tradeoff is unnecessary if an orthogonal-specification design principle is practiced: specify how a simulator is to be implemented separately from what it is implementing and then synthesize a simulator from the combined specifications. We show that the use of an Architectural Description Language (ADL) with constructs for implementation style specification makes it possible to synthesize interfaces with different implementation styles with reasonable effort.