added discrete event simulator for instruction fetch

.vscode/launch.json

@@ -9,7 +9,7 @@
             "name": "Launch Current File",
             "request": "launch",
             "mainClass": "${file}",
-            "args": ["assignment-1/src/descending.asm", "descending.out"]
+            "args": ["assignment-5/src/configuration/config.xml", "assignment-5/src/hello.txt", "assignment-5/supporting_files/test_cases/descending.out"]
         },
         {
             "type": "java",

assignment-4/src/hello.txt

@@ -1,4 +1,4 @@
-Number of instructions executed = 5
+Number of instructions executed = 6
-Number of cycles taken = 14
+Number of cycles taken = 16
-Number of data hazards = 3
+Number of data hazards = 6
-Number of control hazards = 2
+Number of control hazards = 0

assignment-4/src/processor/pipeline/OperandFetch.java

@@ -17,7 +17,7 @@ public class OperandFetch {
 	OF_EX_LatchType OF_EX_Latch;
 	IF_EnableLatchType IF_EnableLatch;
 	static OperationType[] opTypes = OperationType.values();
-	boolean Proceed;
+	public boolean Proceed;
 	Queue<Integer> queue;
 	boolean isEnd;
 	
@@ -197,7 +197,7 @@ public class OperandFetch {
 			}
 		}
 		else if (!Proceed) {
-			Proceed = true;
+			// Proceed = true;
 			System.out.println("\n\nControl Hazard - Interlock\n\n");
 		}
 		updateQueue(addtoqueue);

assignment-5/bin/hello.txt

@@ -1,4 +1,4 @@
-Number of instructions executed = 421
+Number of instructions executed = 7609
-Number of cycles taken = 992
+Number of cycles taken = 11172
-Number of data hazards = 441
+Number of data hazards = 0
-Number of control hazards = 63
+Number of control hazards = 176

assignment-5/src/generic/Simulator.java

@@ -69,6 +69,7 @@ public class Simulator {
 			processor.getRWUnit().performRW();
 			processor.getMAUnit().performMA();
 			processor.getEXUnit().performEX();
+			eventQueue.processEvents();
 			processor.getOFUnit().performOF();
 			processor.getIFUnit().performIF();
 			Clock.incrementClock();

assignment-5/src/hello.txt

@@ -1,4 +1,4 @@
-Number of instructions executed = 5
+Number of instructions executed = 926
-Number of cycles taken = 14
+Number of cycles taken = 1169
-Number of data hazards = 3
+Number of data hazards = 0
-Number of control hazards = 2
+Number of control hazards = 10

assignment-5/src/processor/memorysystem/MainMemory.java

@@ -1,6 +1,15 @@
 package processor.memorysystem;
 
-public class MainMemory {
+import generic.Element;
+import generic.Event;
+import generic.ExecutionCompleteEvent;
+import generic.MemoryReadEvent;
+import generic.MemoryResponseEvent;
+import generic.MemoryWriteEvent;
+import generic.Simulator;
+import processor.Clock;
+
+public class MainMemory implements Element{
 	int[] memory;
 	
 	public MainMemory()
@@ -32,4 +41,37 @@ public class MainMemory {
 		sb.append("\n");
 		return sb.toString();
 	}
+
+	@Override
+	public void handleEvent(Event e) {
+		if (e.getEventType() == Event.EventType.MemoryRead) {
+			System.out.println("Memory Read Event Happening");
+			MemoryReadEvent event = (MemoryReadEvent) e ; 
+
+			System.out.println(getWord(event.getAddressToReadFrom()));
+			Simulator.getEventQueue().addEvent( 
+				new MemoryResponseEvent( 
+					Clock.getCurrentTime(), 
+					this, 
+					event.getRequestingElement(), 
+					getWord(event.getAddressToReadFrom())
+				)
+			); 
+		}
+		else if(e.getEventType() == Event.EventType.MemoryWrite) {
+			System.out.println("Memory Write Event Happening");
+			MemoryWriteEvent event = (MemoryWriteEvent) e ; 
+			System.out.println(getWord(event.getAddressToWriteTo()));
+
+			this.setWord(event.getAddressToWriteTo(), event.getValue());
+			Simulator.getEventQueue().addEvent(
+				new ExecutionCompleteEvent(
+					Clock.getCurrentTime(), 
+					this, 
+					event.getRequestingElement())
+			);
+		}
+	}
+
+	
 }

assignment-5/src/processor/pipeline/Execute.java

@@ -160,7 +160,7 @@ public class Execute {
 				break;
 				case end:
 				{
-					containingProcessor.getRegisterFile().setProgramCounter(containingProcessor.getRegisterFile().getProgramCounter()-1);
+					// containingProcessor.getRegisterFile().setProgramCounter(containingProcessor.getRegisterFile().getProgramCounter()-1);
 					containingProcessor.getOFUnit().setisEnd(true);
 					break;
 				}

assignment-5/src/processor/pipeline/IF_OF_LatchType.java

@@ -4,6 +4,8 @@ public class IF_OF_LatchType {
 	
 	boolean OF_enable;
 	int instruction;
+	boolean IF_busy=false;
+	boolean IF_branching_busy=false;
 	
 	public IF_OF_LatchType()
 	{
@@ -26,4 +28,19 @@ public class IF_OF_LatchType {
 		this.instruction = instruction;
 	}
 
+    public boolean isIF_busy() {
+        return IF_busy;
+    }
+
+	public void setIF_busy(boolean iF_busy) {
+		IF_busy = iF_busy;
+	}
+
+	public boolean isIF_branching_busy() {
+		return IF_branching_busy;
+	}
+
+	public void setIF_branching_busy(boolean iF_branching_busy) {
+		IF_branching_busy = iF_branching_busy;
+	}
 }

assignment-5/src/processor/pipeline/InstructionFetch.java

@@ -1,8 +1,15 @@
 package processor.pipeline;
 
+import configuration.Configuration;
+import generic.Element;
+import generic.Event;
+import generic.MemoryReadEvent;
+import generic.MemoryResponseEvent;
+import generic.Simulator;
+import processor.Clock;
 import processor.Processor;
 
-public class InstructionFetch {
+public class InstructionFetch implements Element{
 	
 	Processor containingProcessor;
 	IF_EnableLatchType IF_EnableLatch;
@@ -18,27 +25,65 @@ public class InstructionFetch {
 	}
 	
 	public void performIF()
-	{	if(!IF_EnableLatch.isFreeze()){
+	{
-			if(EX_IF_Latch.isIF_enable()){
+			if(EX_IF_Latch.isIF_enable() && !IF_OF_Latch.isIF_branching_busy()){
-				containingProcessor.getRegisterFile().setProgramCounter(EX_IF_Latch.getPC()-1);
+				containingProcessor.getRegisterFile().setProgramCounter(EX_IF_Latch.getPC());
+				int currentPC = containingProcessor.getRegisterFile().getProgramCounter();
+
+				Simulator.getEventQueue().addEvent(
+						new MemoryReadEvent(
+								Clock.getCurrentTime()+Configuration.mainMemoryLatency,
+								this,
+								containingProcessor.getMainMemory(),
+								currentPC
+								)
+						);
+				IF_OF_Latch.setIF_branching_busy(true);
+
+
 				EX_IF_Latch.setIF_enable(false);
 				IF_OF_Latch.setOF_enable(false);
 				System.out.println("IF: PC set to " + EX_IF_Latch.getPC());
 
 			} // if EX_IF_Latch is enabled, set PC to EX_IF_Latch's PC and wait for next cycle (1 nop)
-			else if(IF_EnableLatch.isIF_enable() || EX_IF_Latch.isIF_enable())
+			else if(IF_EnableLatch.isIF_enable())
 			{
+				if(IF_OF_Latch.isIF_busy()){
+					return;
+				}
 				int currentPC = containingProcessor.getRegisterFile().getProgramCounter();
-				int newInstruction = containingProcessor.getMainMemory().getWord(currentPC);
+				// int newInstruction = containingProcessor.getMainMemory().getWord(currentPC);
-				IF_OF_Latch.setInstruction(newInstruction);
+				// IF_OF_Latch.setInstruction(newInstruction);
-				containingProcessor.getRegisterFile().setProgramCounter(currentPC + 1);
+				// containingProcessor.getRegisterFile().setProgramCounter(currentPC + 1);
+				
+				Simulator.getEventQueue().addEvent(
+					new MemoryReadEvent(
+						Clock.getCurrentTime()+ Configuration.mainMemoryLatency,
+						this,
+						containingProcessor.getMainMemory(),
+						currentPC
+					)
+				);
+				IF_OF_Latch.setIF_busy(true);
+				IF_OF_Latch.setOF_enable(false);
 
-				IF_EnableLatch.setIF_enable(true);
-				IF_OF_Latch.setOF_enable(true);
 			}
-		}else{
+	}
+
+	@Override
+	public void handleEvent(Event e) {
+		if(IF_OF_Latch.isIF_branching_busy()){
 			IF_EnableLatch.setFreeze(false);
+			IF_OF_Latch.setIF_branching_busy(false);
+			containingProcessor.getOFUnit().Proceed = true;
+			System.out.println("IF: Unfreezing");
+			return;
 		}
+		MemoryResponseEvent event = (MemoryResponseEvent) e;
+		IF_OF_Latch.setInstruction(event.getValue());
+		containingProcessor.getRegisterFile().setProgramCounter(containingProcessor.getRegisterFile().getProgramCounter() + 1);
+		IF_OF_Latch.setOF_enable(true);
+		IF_OF_Latch.setIF_busy(false);
 	}
 
 }

assignment-5/src/processor/pipeline/OperandFetch.java

@@ -17,7 +17,7 @@ public class OperandFetch {
 	OF_EX_LatchType OF_EX_Latch;
 	IF_EnableLatchType IF_EnableLatch;
 	static OperationType[] opTypes = OperationType.values();
-	boolean Proceed;
+	public boolean Proceed;
 	Queue<Integer> queue;
 	boolean isEnd;
 	
@@ -197,7 +197,7 @@ public class OperandFetch {
 			}
 		}
 		else if (!Proceed) {
-			Proceed = true;
+			// Proceed = true;
 			System.out.println("\n\nControl Hazard - Interlock\n\n");
 		}
 		updateQueue(addtoqueue);