private int InstructionExecutionLoopCore(bool isSingleInstruction)
{
ClockSynchronizer.Start();
executionContext = new InstructionExecutionContext();
StopReason = StopReason.NotApplicable;
State = ProcessorState.Running;
var totalTStates = 0;
while (!executionContext.MustStop)
{
executionContext.StartNewInstruction();
FireBeforeInstructionFetchEvent();
if (executionContext.MustStop)
{
break;
}
var executionTStates = ExecuteNextOpcode();
totalTStates = executionTStates + executionContext.AccummulatedMemoryWaitStates;
TStatesElapsedSinceStart += (ulong)totalTStates;
TStatesElapsedSinceReset += (ulong)totalTStates;
ThrowIfNoFetchFinishedEventFired();
if (!isSingleInstruction)
{
CheckAutoStopForHaltOnDi();
CheckForAutoStopForRetWithStackEmpty();
CheckForLdSpInstruction();
}
FireAfterInstructionExecutionEvent(totalTStates);
if (!IsHalted)
{
IsHalted = executionContext.IsHaltInstruction;
}
var interruptTStates = AcceptPendingInterrupt();
TStatesElapsedSinceStart += (ulong)interruptTStates;
TStatesElapsedSinceReset += (ulong)interruptTStates;
if (isSingleInstruction)
{
executionContext.StopReason = StopReason.ExecuteNextInstructionInvoked;
}
else
{
ClockSynchronizer.TryWait(totalTStates);
}
}
ClockSynchronizer.Stop();
this.StopReason = executionContext.StopReason;
this.State =
StopReason == StopReason.PauseInvoked
? ProcessorState.Paused
: ProcessorState.Stopped;
executionContext = null;
return(totalTStates);
}
