精确计算代码段执行时间

#include <cstdio>

#include <Windows.h>

#include <atlbase.h>

#include <Tlhelp32.h>

#include <time.h>

//...........

int WINAPI findString(int lpmem,int memsize,int lpString,int StringSize,int AddrList)//; //

{

int nRet=-1;

__asm

{

pushad;

mov edx,lpmem;

add edx,memsize;

sub edx,StringSize;

mov edi,lpmem;

mov esi,lpString;

mov eax,[esi];

mov ecx,[esi+4];

mov ebx,AddrList;

LableBegin:

cmp eax,[edi];

jnz LableNext;

cmp ecx,[edi+4];

jnz LableNext;

mov ecx,StringSize;

push edi;

repz cmpsb;

pop edi;

mov esi,lpString;

mov ecx,[esi+4];

jnz LableNext;

LableSave:

mov ebx,edi;

add ebx,4;

LableNext:

inc edi;

cmp edi,edx;

jnz LableBegin;

LableRet:

mov nRet,ebx;

popad;

}

return nRet;

}

//>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

int SearchByteShuZu(byte * bForSearch,int ifLen, byte* bWaitSearch, int iwLen,int iFirstSearchPos)

{//int SearchByteShuZu(byte * bForSearch,int ifLen, byte* bWaitSearch, int iwLen,int iFirstSearchPos);//寻找字节集数组(待寻找的,待寻找的最大长度,要寻找的,要寻找的长度,起始寻找位置) 返回-1 为未找到 位置从0开始

int iCurrentPos=0;//待搜索位置

if (iFirstSearchPos>ifLen)//超过待搜索的长度

{

return -1;

}

if (iwLen>ifLen)//要搜索的长度比 待搜索的长度大 返回

{

return -1;

}

if (iwLen==0||ifLen==0)

{

return -1;//0 返回

}

// bForSearch+=iFirstSearchPos;//设置起始搜索位置

iCurrentPos+=iFirstSearchPos;//设置起始搜索位置

bForSearch+=iCurrentPos;//设置指针 对应

while(1)

{

while(*bForSearch!=*bWaitSearch)//找到第一个相同的

{

iCurrentPos+=1;//当前搜索位置前进1

bForSearch+=1;//当前指针前进1

if (iCurrentPos>ifLen) //长度超过待搜索的整体长度返回

{

return -1;

}

}

for (int i=0;i<iwLen;++i)//开始对比

{

if (*(bForSearch+i)!=*(bWaitSearch+i))

{

iCurrentPos+=1;//当前搜索位置前进1

bForSearch+=1;//当前指针前进1

//设置下指针前进1

break;//找到一个不同的 跳出

}

if (i+1==iwLen)

{

return iCurrentPos;//找到列

}

}

}

}

__int64 FileTimeToQuadWord(PFILETIME pft)

{

return Int64ShllMod32(pft->dwHighDateTime,32)|pft->dwLowDateTime;

}

__int64 GetThreadRunTime() //取线程当前占用cpu时间 单位:100ns(纳秒)

{

FILETIME ftKernelTime,ftUserTime,ftDummy;

GetThreadTimes(GetCurrentThread(),&ftDummy,&ftDummy,&ftKernelTime,&ftUserTime);

return FileTimeToQuadWord(&ftKernelTime)+FileTimeToQuadWord(&ftUserTime);

}

char szFind[0x20000000];

int main()

{

LPSTR szsea="45644564";

__int64 qwStartTime=0,qwTime=0;

qwStartTime=GetThreadRunTime();//setvalue

srand(time(NULL));

for (int i=0;i<sizeof(szFind)/sizeof(DWORD);i++)

{

((DWORD*)szFind)[i]=rand();

}

qwTime=GetThreadRunTime()-qwStartTime;

printf("/r/nSetValue:%I64d*100ns %dms/r/n",qwTime,qwTime/1000/10);

qwStartTime=GetThreadRunTime();

findString((int)szFind,sizeof(szFind),(int)szsea,8,0);

qwTime=GetThreadRunTime()-qwStartTime;

printf("/r/nfindString:%I64d*100ns %dms/r/n",qwTime,qwTime/1000/10);

qwStartTime=GetThreadRunTime();

SearchByteShuZu((byte*)szFind,sizeof(szFind),(byte*)szsea,8,0);

qwTime=GetThreadRunTime()-qwStartTime;

printf("/r/nSearchByteShuZu:%I64d*100ns %dms/r/n",qwTime,qwTime/1000/10);

return 0;

} 

GetThreadTimes 获取的时间只是cpu执行时间  不包含睡眠时间及等待事件的时间

效率对比用

int memfind(const char *mem, const char *str, int sizem, int sizes)

{

int da,i,j;

if (sizes == 0) da = strlen(str);

else da = sizes;

for (i = 0; i < sizem; i++)

{

for (j = 0; j < da; j ++)

if (mem[i+j] != str[j]) break;

if (j == da) return i;

}

return -1;

}