함수 속도 측정

{
  LARGE_INTEGER Frequency;
  LARGE_INTEGER BeginTime;
  LARGE_INTEGER Endtime;
  __int64 elapsed;
  double duringtime;
     
  //프로그램이나 클래스 시작부분에
  QueryPerformanceFrequency( &Frequency );
 
  //사용하고자 하는 부분
  QueryPerformanceCounter( &BeginTime );
 
///////////////////////////////// 
  QueryPerformanceCounter( &Endtime );
  elapsed = Endtime.QuadPart- BeginTime.QuadPart; 
  duringtime = (double)elapsed / (double)Frequency.QuadPart;
 
  duringtime *=1000;  //ms로 변환
TRACE(_T("---------%f\r\n"), duringtime);
}