我正在编写一个程序来模拟缓存。我正在使用QVector作为结构。我有一个QVector的QVector的整数。但是,当我尝试编辑整数时,会导致运行时错误:
*** glibc detected *** ./CompOrgProject3: free(): invalid next size (fast): 0x00000000010d2550 ***
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x7eb96)[0x7fd31b469b96]
./CompOrgProject3[0x402558]
./CompOrgProject3[0x402bf3]
./CompOrgProject3[0x402005]
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed)[0x7fd31b40c76d]
./CompOrgProject3[0x4023c1]
======= Memory map: ========
00400000-00405000 r-xp 00000000 08:01 404625 /home/**/Documents/CompOrgProject3/CompOrgProject3
00604000-00605000 r--p 00004000 08:01 404625 /home/**/Documents/CompOrgProject3/CompOrgProject3
00605000-00606000 rw-p 00005000 08:01 404625 /home/**/Documents/CompOrgProject3/CompOrgProject3
010cb000-010ec000 rw-p 00000000 00:00 0
这是正在运行的鳕鱼: 主:
#include <fstream>
#include <QStringList>
#include <iostream>
#include <QFile>
#include <QTextStream>
#include <QDebug>
#include <cstdlib>
#include <string>
#include "cache.h"
using namespace std;
int main()
{
QFile instFile;
instFile.setFileName("test.trace");
int cacheSizes[4] = {1024, 4096, 16384, 65536};
int blockSizes[4] = {8, 16, 32, 64};
QString types[4] = {"DM", "2W", "4W" , "FA"};
if(!instFile.open(QIODevice::ReadOnly))
{
return -1;
}
QTextStream in(&instFile);
QStringList instList;
while(!in.atEnd())
{
QString temp;
temp = in.readLine();
instList.append(temp);
}
for(int i = 0; i < instList.size(); i++)
{
cout << instList.at(i).toStdString() << "\n";
}
for(int i = 0; i < 4; i++)
{
for(int j = 0; j < 4; j++)
{
for(int k = 0; k < 4; k++)
{
Cache c(cacheSizes[i], blockSizes[j], types[k], instList);
c.simulateCache();
}
}
}
return 0;
}
这是我有QVectors的模拟函数:
void Cache::simulateCache()
{
if(this->instList.size() < 1)
{
screenOut << "Cannot simulate cache: there are no instructions";
}
else
{
screenOut << "Starting simulation...\n";
int entry_per_block = block_size / 4;
block_count = cache_size / block_size;
QVector<QVector<int> > ca(block_count);
for(int i = 0; i < block_count; i++)
{
ca[i].resize(entry_per_block);
}
screenOut << "QVector created.\n";
for(int i = 0; i < this->instList.size(); i++)
{
QStringList inst_parts = instList.at(i).split(QRegExp(" "));
QString instType = inst_parts.at(0);
int mem_addr = inst_parts.at(1).toInt(0, 16);
if(this->type.compare("DM") == 0)
{
int block_index = (int) (mem_addr / block_size) % block_count;
int block_offset = mem_addr % block_size;
if(ca.at(block_index).at(block_offset) == mem_addr)
{
this->hits++;
if(instType.compare("W") == 0)
{
this->cacheToMem+=block_size;
}
}
else
{
this->misses++;
this->memToCache += block_size;
ca[block_index][block_offset] = mem_addr;
if(instType.compare("W") == 0)
{
this->cacheToMem+=block_size;
}
for(int i = block_offset - 1; i >= 0; i--)
{
//ca[block_index][i] = mem_addr - ((block_offset - i) * 4);
//ca[block_index].insert(i, mem_addr - ((block_offset - i) * 4) );
}
for(int i = block_offset + 1; i < entry_per_block; i++)
{
//ca[block_index][i] = mem_addr + ((i - block_offset) * 4));
//ca[block_index].insert(i, mem_addr + ((i - block_offset) * 4));
}
}
}
}
hit_rate = hits / instList.size();
screenOut << hit_rate << "\n";
}
}
这是导致错误的行,我相信:
ca[block_index][block_offset] = mem_addr;
答案 0 :(得分:1)
以下是使用嵌套QVector
的简单示例。您可能还想查看此链接:
http://www.qtcentre.org/threads/49026-2D-array-in-Qt-QVector-or-QList
此外,您可能希望在代码中添加一些qDebug
语句,以查看您是否拥有您认为的元素数量。
QVector < QVector < int > > matrix;
matrix.resize(10);
for(int i = 0; i< matrix.size(); i++)
{
// Note that you can't use foreach here!
matrix[i].resize(10);
}
// Sanity check:
qDebug() << matrix.size() << matrix.at(0).size();
for(int r = 0; r < matrix.size(); r++)
{
for(int c = 0; c < matrix.at(r).size(); c++)
{
matrix[r][c] = 10;
// qDebug() << matrix[r][c];
}
}
希望有所帮助。
编辑:这是另一个检查的例子: