Re-evaluates the combinational logic for the given timestep - used if a combinational input has changed

runFastSimulationCore with its invocation recorded: one SimLog entry per call that advances the clock. The renderer's progress loop is repeated timed calls to this, so each progress update is one record; calls that find nothing to do (the wave viewer re-asking for a tick it already has, on every render) are not recorded, or they would flood the ring.