CacheSim/set.cpp

#include "set.h"
#include <iostream>

using std::vector;
using CacheSim::Block;
using CacheSim::Set;

using std::cout;
using std::endl;

Set::Set(short waySize, short tagSize){
    this->waySize = waySize;
    this->emptySize = waySize;

    for(int i=0; i<waySize; i++){
        this->blocks.push_back(Block(tagSize));
    }
}

bool Set::read(vector<bool> tag, short offset){
    // HIT 的情況
    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
            this->countAccess();        // 更新計算所有 way access 的時間點
            cout << "HIT: 在 " << i << " way 找到！" << endl;
            return true;
        }
    }

    // MISS 的情況，需要寫入 $
    if(this->emptySize > 0){
        for(int i=0; i<this->waySize; i++){
            if(this->blocks[i].getValid() == false){
                cout << "MISS: 在 " << i <<" way 寫入資料" << endl;
                this->blocks[i].update(tag);    // 更新 tag
                this->blocks[i].access();
                break;
            }
        }
        this->emptySize--;
    }else{                      // 沒有空位，需要 replace
        short maxIndex = -1, maxTime = -1;
        short tempTime;

        // 找最久沒被 access 的 index
        for(int i=0; i<this->waySize; i++){
            tempTime = this->blocks[i].getAccessTime();
            if(tempTime > maxTime){
                maxTime = tempTime;
                maxIndex = i;
            }
        }

        // update
        cout << "MISS: way 滿了，找到 " << maxIndex << " 在 " << maxTime << " 前更新" << endl;
        this->blocks[maxIndex].update(tag);
        this->blocks[maxIndex].access();
    }
    
    this->countAccess();
    return false;
}

void Set::countAccess(){
    for(int i=0; i<this->waySize; i++){
        this->blocks[i].countAccess();
    }
    for(int i=0; i<20; i++){
        cout << "=" ;
    }
    cout << "way 狀態";
    for(int i=0; i<20; i++){
        cout << "=";
    }
    cout<<endl;

    for(int i=0; i<this->waySize; i++){
        cout << this->blocks[i].getAccessTime() << " ";
    }
    cout<<endl;

    for(int i=0; i<45; i++){
        cout << "=";
    }
    cout<<endl;
}