private void markReservationStationFull(ReservationStationEntry resStationEntry)
{
switch (resStationEntry.instr.executionType)
{
case Instruction.ExecutionType.Branch:
Statistics.branchExecutionUnitsFull++;
break;
case Instruction.ExecutionType.FloatingPoint:
Statistics.floatingExecutionUnitsFull++;
break;
case Instruction.ExecutionType.Logical:
case Instruction.ExecutionType.Integer:
Statistics.integerExecutionUnitsFull++;
break;
case Instruction.ExecutionType.Mem:
Statistics.memoryExecutionUnitsFull++;
break;
case Instruction.ExecutionType.MultDiv:
Statistics.multDivExecutionUnitsFull++;
break;
default:
System.Console.WriteLine("ERROR:ExecutionStage.canIssue, unknown Execution Type");
break;
}
}
private ExecutionUnit[] getTargetUnitArray(ReservationStationEntry resStationEntry)
{
ExecutionUnit[] targetUnitArray;
switch (resStationEntry.instr.executionType)
{
case Instruction.ExecutionType.Branch:
targetUnitArray = this.branchUnits;
break;
case Instruction.ExecutionType.FloatingPoint:
targetUnitArray = this.fpUnits;
break;
case Instruction.ExecutionType.Logical:
case Instruction.ExecutionType.Integer:
targetUnitArray = this.intUnits;
break;
case Instruction.ExecutionType.Mem:
targetUnitArray = this.memUnits;
break;
case Instruction.ExecutionType.MultDiv:
targetUnitArray = this.multDivUnits;
break;
default:
System.Console.WriteLine("ERROR:ExecutionStage.canIssue, unknown Execution Type");
targetUnitArray = null;
break;
}
return(targetUnitArray);
}
public void acceptIssue(ReservationStationEntry resStationEntry)
{
ExecutionUnit[] targetUnitArray = this.getTargetUnitArray(resStationEntry);
for (int i = 0; i < targetUnitArray.Length; i++)
{
if (targetUnitArray[i].busy == false)
{
targetUnitArray[i].LoadInstruction(resStationEntry);
break;
}
}
}
public void acceptIssue(ReservationStationEntry resStationEntry)
{
ExecutionUnit[] targetUnitArray = this.getTargetUnitArray(resStationEntry);
for (int i = 0; i < targetUnitArray.Length; i++)
{
if (targetUnitArray[i].busy == false)
{
targetUnitArray[i].LoadInstruction(resStationEntry);
break;
}
}
}
/// <summary>
/// Loads an instruction into the Execution Unit
/// </summary>
/// <param name="_instr"></param>
public void LoadInstruction(ReservationStationEntry _entry)
{
this.entry = _entry;
this.busy = true;
Random rand = new Random();
switch (entry.instr.executionType)
{
case Instruction.ExecutionType.Branch:
this.remainingCycles = Config.branchExeLatency;
break;
case Instruction.ExecutionType.FloatingPoint:
this.remainingCycles = Config.fpExeLatency;
break;
case Instruction.ExecutionType.Logical:
case Instruction.ExecutionType.Integer:
this.remainingCycles = Config.intExeLatency;
break;
case Instruction.ExecutionType.Mem:
this.remainingCycles = Config.memExeLatency;
break;
case Instruction.ExecutionType.MultDiv:
this.remainingCycles = Config.mulDivExeLatency;
break;
default:
System.Console.WriteLine("ERROR:Execution unit constructor, unknown Execution Type");
break;
}
// Check to see if it is a memory instruction so we can add the delays
if (entry.instr.executionType == Instruction.ExecutionType.Mem)
{
// Check to see if we missed level 1
if (rand.Next(100) < Config.level1CacheDataMissPercent)
{
Statistics.level1DataCacheMisses++;
this.remainingCycles += Config.level1CacheMissPenalty;
// Check to see if we missed level 2
if (rand.Next(100) < Config.level2CacheMissPercent)
{
Statistics.level2CacheMisses++;
this.remainingCycles += Config.level2CacheMissPenalty;
}
}
}
}
/// <summary>
/// Tells the Reorder Buffer that execution has finished on an instruction inside the given resEntry
/// </summary>
/// <param name="resStationEntry"></param>
/// <returns>The RRF Tag index</returns>
public int executionFinished(ReservationStationEntry resStationEntry)
{
RobEntry robEntry;
robEntry = this.buffer.FirstOrDefault(_robEntry => _robEntry.instruction == resStationEntry.instr);
if (robEntry == null)
{
System.Console.WriteLine("ROB.executionFinished(): An instruction finished but was not found in the ROB buffer");
return -1;
}
robEntry.finished = true;
return robEntry.renameReg;
}
/// <summary>
/// Tells the Reorder Buffer that execution has finished on an instruction inside the given resEntry
/// </summary>
/// <param name="resStationEntry"></param>
/// <returns>The RRF Tag index</returns>
public int executionFinished(ReservationStationEntry resStationEntry)
{
RobEntry robEntry;
robEntry = this.buffer.FirstOrDefault(_robEntry => _robEntry.instruction == resStationEntry.instr);
if (robEntry == null)
{
System.Console.WriteLine("ROB.executionFinished(): An instruction finished but was not found in the ROB buffer");
return(-1);
}
robEntry.finished = true;
return(robEntry.renameReg);
}
/// <summary>
/// Takes a reservation station entry and checks to see if it can be issued
///
/// This is competed by checking the appropriate list of execution units to
/// see if there is one available
/// <returns>true if the instruction can be issued and false if not</returns>
/// </summary>
public bool canIssue(ReservationStationEntry resStationEntry)
{
ExecutionUnit[] targetUnitArray = this.getTargetUnitArray(resStationEntry);
for (int i = 0; i < targetUnitArray.Length; i++)
{
// if there is room return true
if (targetUnitArray[i].busy == false)
return true;
}
// If we check all of the exeuction units, and they are all busy == true, then there is no room
markReservationStationFull(resStationEntry);
return false;
}
/// <summary>
/// Takes a reservation station entry and checks to see if it can be issued
///
/// This is competed by checking the appropriate list of execution units to
/// see if there is one available
/// <returns>true if the instruction can be issued and false if not</returns>
/// </summary>
public bool canIssue(ReservationStationEntry resStationEntry)
{
ExecutionUnit[] targetUnitArray = this.getTargetUnitArray(resStationEntry);
for (int i = 0; i < targetUnitArray.Length; i++)
{
// if there is room return true
if (targetUnitArray[i].busy == false)
{
return(true);
}
}
// If we check all of the exeuction units, and they are all busy == true, then there is no room
markReservationStationFull(resStationEntry);
return(false);
}
/// <summary>
/// Puts the instruction into the reservation station, filling the entries
/// Note this does not check if ResStation is full, as that check is done at a higher level
/// </summary>
public void ReceiveInstruction(Instruction instr, int robTag)
{
// The reservation station entry we're creating
ReservationStationEntry thisEntry;
// The fields in the entry
int op1 = 0, op2 = 0;
bool valid1 = false, valid2 = false;
SetUpOp(ref op1, ref valid1, instr.source1, instr.source1Imm);
SetUpOp(ref op2, ref valid2, instr.source2, instr.source2Imm);
thisEntry = new ReservationStationEntry(op1, valid1, op2, valid2, robTag, instr);
this.buffer.Add(thisEntry);
} // End ReceiveInstruction
/// <summary>
/// Loads an instruction into the Execution Unit
/// </summary>
/// <param name="_instr"></param>
public void LoadInstruction(ReservationStationEntry _entry)
{
this.entry = _entry;
this.busy = true;
Random rand = new Random();
switch (entry.instr.executionType)
{
case Instruction.ExecutionType.Branch :
this.remainingCycles = Config.branchExeLatency;
break;
case Instruction.ExecutionType.FloatingPoint :
this.remainingCycles = Config.fpExeLatency;
break;
case Instruction.ExecutionType.Logical :
case Instruction.ExecutionType.Integer :
this.remainingCycles = Config.intExeLatency;
break;
case Instruction.ExecutionType.Mem :
this.remainingCycles = Config.memExeLatency;
break;
case Instruction.ExecutionType.MultDiv :
this.remainingCycles = Config.mulDivExeLatency;
break;
default :
System.Console.WriteLine("ERROR:Execution unit constructor, unknown Execution Type");
break;
}
// Check to see if it is a memory instruction so we can add the delays
if (entry.instr.executionType == Instruction.ExecutionType.Mem)
{
// Check to see if we missed level 1
if (rand.Next(100) < Config.level1CacheDataMissPercent)
{
Statistics.level1DataCacheMisses++;
this.remainingCycles += Config.level1CacheMissPenalty;
// Check to see if we missed level 2
if (rand.Next(100) < Config.level2CacheMissPercent)
{
Statistics.level2CacheMisses++;
this.remainingCycles += Config.level2CacheMissPenalty;
}
}
}
}
/// <summary>
/// Puts the instruction into the reservation station, filling the entries
/// Note this does not check if ResStation is full, as that check is done at a higher level
/// </summary>
public void ReceiveInstruction(Instruction instr, int robTag)
{
// The reservation station entry we're creating
ReservationStationEntry thisEntry;
// The fields in the entry
int op1 = 0, op2 = 0;
bool valid1 = false, valid2 = false;
SetUpOp(ref op1, ref valid1, instr.source1, instr.source1Imm);
SetUpOp(ref op2, ref valid2, instr.source2, instr.source2Imm);
thisEntry = new ReservationStationEntry(op1, valid1, op2, valid2, robTag, instr);
this.buffer.Add(thisEntry);
}
private ExecutionUnit[] getTargetUnitArray(ReservationStationEntry resStationEntry)
{
ExecutionUnit[] targetUnitArray;
switch (resStationEntry.instr.executionType)
{
case Instruction.ExecutionType.Branch:
targetUnitArray = this.branchUnits;
break;
case Instruction.ExecutionType.FloatingPoint:
targetUnitArray = this.fpUnits;
break;
case Instruction.ExecutionType.Logical:
case Instruction.ExecutionType.Integer:
targetUnitArray = this.intUnits;
break;
case Instruction.ExecutionType.Mem:
targetUnitArray = this.memUnits;
break;
case Instruction.ExecutionType.MultDiv:
targetUnitArray = this.multDivUnits;
break;
default:
System.Console.WriteLine("ERROR:ExecutionStage.canIssue, unknown Execution Type");
targetUnitArray = null;
break;
}
return targetUnitArray;
}
private void markReservationStationFull(ReservationStationEntry resStationEntry)
{
switch (resStationEntry.instr.executionType)
{
case Instruction.ExecutionType.Branch:
Statistics.branchExecutionUnitsFull++;
break;
case Instruction.ExecutionType.FloatingPoint:
Statistics.floatingExecutionUnitsFull++;
break;
case Instruction.ExecutionType.Logical:
case Instruction.ExecutionType.Integer:
Statistics.integerExecutionUnitsFull++;
break;
case Instruction.ExecutionType.Mem:
Statistics.memoryExecutionUnitsFull++;
break;
case Instruction.ExecutionType.MultDiv:
Statistics.multDivExecutionUnitsFull++;
break;
default:
System.Console.WriteLine("ERROR:ExecutionStage.canIssue, unknown Execution Type");
break;
}
}
