feat: LRU Replace Policy

Makefile

@@ -0,0 +1,9 @@
+CC = g++
+
+all: sim
+
+sim: main.cpp block.cpp set.cpp simulator.cpp
+	$(CC) main.cpp block.cpp set.cpp simulator.cpp -o sim
+
+clean:
+	rm sim

main.cpp

@@ -27,10 +27,25 @@ int main(){
 	CacheSim::Simulator sim(machineBits, setSize, waySize, tagSize);
 
 	std::string action, address;
+	bool status;
+	std::vector<std::pair<std::string, bool>> result;
 	while(std::cin >> action >> address){
 		std::cout << "action: "<< action << " address: " << address << std::endl; 
-		sim.read(address);
+		status = sim.read(address);
+		result.push_back(std::make_pair(address, status));
 		std::cout << std::endl << std::endl;
 	}
-	
+
+	int allCount = 0, hitCount = 0;
+	for(int i=0; i<result.size(); i++){
+		std::cout << result[i].first << "... ";
+		allCount++;
+		if(result[i].second){
+			hitCount++;
+			std::cout << "HIT" << std::endl;
+		}else{
+			std::cout << "MISS" << std::endl;
+		}
+	}
+	std::cout << "Hit rate: " << (double)hitCount/allCount*100 << "%" << std::endl;
 }

set.cpp

@@ -19,10 +19,12 @@ Set::Set(short waySize, short tagSize){
 
 bool Set::read(vector<bool> tag, short offset){
     // HIT 的情況
+    short baseAccessTime;       // 被替換掉的 block ，它的 access time
     for(int i=0; i<this->waySize; i++){
         if(this->blocks[i].getValid() && this->blocks[i].getTag() == tag){      // valid bit == true 且 tag 相同
-            this->blocks[i].access();   // 重設 access 的時間點
+            baseAccessTime= this->blocks[i].getAccessTime();
-            this->countAccess();        // 更新計算所有 way access 的時間點
+            this->blocks[i].access();
+            this->countAccess(baseAccessTime);        // 更新計算所有 way access 的時間點
             cout << "HIT: 在 " << i << " way 找到！" << endl;
             return true;
         }
@@ -35,6 +37,7 @@ bool Set::read(vector<bool> tag, short offset){
                 cout << "MISS: 在 " << i <<" way 寫入資料" << endl;
                 this->blocks[i].update(tag);    // 更新 tag
                 this->blocks[i].access();
+                baseAccessTime = this->waySize; // 每個都要更新
                 break;
             }
         }
@@ -43,7 +46,7 @@ bool Set::read(vector<bool> tag, short offset){
         short maxIndex = -1, maxTime = -1;
         short tempTime;
 
-        // 找最久沒被 access 的 index
+        // 找最久沒被 access 的 block index
         for(int i=0; i<this->waySize; i++){
             tempTime = this->blocks[i].getAccessTime();
             if(tempTime > maxTime){
@@ -54,17 +57,28 @@ bool Set::read(vector<bool> tag, short offset){
 
         // update
         cout << "MISS: way 滿了，找到 " << maxIndex << " 在 " << maxTime << " 前更新" << endl;
+        baseAccessTime = this->blocks[maxIndex].getAccessTime();
         this->blocks[maxIndex].update(tag);
         this->blocks[maxIndex].access();
+
+        for(int i=0; i<this->waySize; i++){
+            vector<bool> t = this->blocks[i].getTag();
+            for(int j=0; j<t.size(); j++){
+                cout << t[j];
+            }
+            cout << endl;
+        }
     }
     
-    this->countAccess();
+    this->countAccess(baseAccessTime);
     return false;
 }
 
-void Set::countAccess(){
+void Set::countAccess(short baseAccessTime){
     for(int i=0; i<this->waySize; i++){
-        this->blocks[i].countAccess();
+        if(this->blocks[i].getAccessTime() < baseAccessTime){   // 小於 basetime 就 ++，補足 basetime 缺的 hole
+            this->blocks[i].countAccess();
+        }
     }
     for(int i=0; i<20; i++){
         cout << "=" ;

set.h

@@ -15,7 +15,7 @@ namespace CacheSim{
     public:
         Set(short waySize, short tagSize);
         bool read(vector<bool> tag, short offset);
-        void countAccess();
+        void countAccess(short baseAccessTime);
 
     };
 }

simulator.cpp

@@ -22,11 +22,9 @@ bool Simulator::read(string address){
     std::cout << std::endl;
     short index = this->getValue(addrBits, "index");
     short offset = this->getValue(addrBits, "offset");
-    vector<bool> tag;
+    vector<bool> tag(addrBits.begin(), addrBits.begin()+this->tagSize);
-    tag.assign(addrBits.begin(), addrBits.begin()+this->tagSize);
     std::cout<<"更新 index: "<<index<<std::endl;
     return this->sets[index].read(tag, offset);
-    // return 0;
 }
 
 bool Simulator::write(string address){