Вот, можете сами проверить, построить распределение вероятностей... Вроде компилируется.
| Код | // main.cpp
#include <cstdio>
#include <timer.hpp>
class X: public Timer
{
__int64 tick;
double ms_max;
int out, count;
public:
X ();
void activate ();
~X ();
};
void main ()
{
init_timer ();
X a;
a.get_ready ();
unsigned timer = GetTickCount () + 30 * 1000;
while (timer > GetTickCount ());
}
X::X (): Timer (2, 0), tick (0), ms_max (-1.0), out (0), count (0)
{
tick = exec_rdtsc ();
}
X::~X ()
{
printf ("%G%%\n", out / count * 100.0); // Процент «непопаданий»
}
void X::activate ()
{
__int64 tick2 = exec_rdtsc ();
__int64 delta = tick2 - tick;
tick = tick2;
double ms = double (delta) / timer_scale;
if (ms > delay)
{
printf ("%G\n", ms);
ms_max = ms;
++out;
}
++count;
}
|
«Нашлепка» для таймера:
| Код | // timer.hpp
#pragma once
#include <tchar.h>
#include <windows.h>
#include <mmsystem.h>
void init_timer ();
__int64 exec_rdtsc ();
extern __int64 timer_scale;
class Timer
{
friend void CALLBACK timer_callback (UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
public:
Timer (unsigned delay, unsigned accuracy): handle (NULL), delay (delay), accuracy (accuracy) { }
virtual bool get_ready ();
virtual void complete ();
virtual ~Timer () { complete (); }
protected:
Timer (const Timer&);
Timer& operator = (const Timer&);
virtual void activate () = 0;
MMRESULT handle;
unsigned delay, accuracy;
};
|
Реализация «нашлепки» для таймера:
| Код | // timer.cpp
#include <timer.hpp>
const int TIMER_TEST_TIME = 1000; // msec
__int64 timer_scale;
__int64 exec_rdtsc ()
{
static __int64 result;
_asm
{
rdtsc // ReaD from Time Stamp Counter
mov ebx, offset result
mov dword ptr [ebx], eax
mov dword ptr [ebx + 4], edx
}
return result;
}
void init_timer ()
{
__int64 start_timer, stop_timer;
HANDLE current_process = GetCurrentProcess ();
DWORD common_priority = GetPriorityClass (current_process);
SetPriorityClass (current_process, REALTIME_PRIORITY_CLASS);
DWORD tick_count = GetTickCount (), timer = tick_count + TIMER_TEST_TIME;
start_timer = exec_rdtsc ();
while (timer > GetTickCount ());
stop_timer = exec_rdtsc ();
SetPriorityClass (current_process, common_priority);
timer_scale = (stop_timer - start_timer) / TIMER_TEST_TIME;
}
void CALLBACK timer_callback (UINT uTimerID, UINT uMsg, DWORD_PTR thread_ptr, DWORD_PTR dw1, DWORD_PTR dw2)
{
Timer& timer = *cast <Timer*>(thread_ptr);
timer.activate ();
}
bool Timer::get_ready ()
{
timeBeginPeriod (accuracy);
handle = timeSetEvent (delay, accuracy, timer_callback, cast <DWORD_PTR>(this), TIME_PERIODIC);
return handle != NULL;
}
void Timer::complete ()
{
if (handle != NULL)
{
timeKillEvent (handle);
handle = NULL;
timeEndPeriod (accuracy);
}
}
|
timer > x из командной строки пишет у меня в x следующее:
| Цитата | 15.8527
2.96936
2.97209
2.96961
2.96853
2.97072
2.96829
2.96918
2.96884
2.96854
2.96822
2.96965
2.9632
2.96945
2.9695
2.9695
2.96833
2.96683
2.96956
...
2.96898
2.97007
2.96409
2.9694
2.96743
2.27022
2.68064
2.01943
2.96736
2.96892
0%
|
А потом, при желании, это можно запихать в фак. |