eigen/bench/BenchTimer.h
2009-10-20 22:08:13 +02:00

104 lines
2.4 KiB
C++

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr>
// Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com>
//
// Eigen is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 3 of the License, or (at your option) any later version.
//
// Alternatively, you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of
// the License, or (at your option) any later version.
//
// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License and a copy of the GNU General Public License along with
// Eigen. If not, see <http://www.gnu.org/licenses/>.
#ifndef EIGEN_BENCH_TIMER_H
#define EIGEN_BENCH_TIMER_H
#ifndef WIN32
#include <sys/time.h>
#include <unistd.h>
#else
#define NOMINMAX
#include <windows.h>
#endif
#include <cstdlib>
#include <numeric>
namespace Eigen
{
/** Elapsed time timer keeping the best try.
*/
class BenchTimer
{
public:
BenchTimer()
{
#ifdef WIN32
LARGE_INTEGER freq;
QueryPerformanceFrequency(&freq);
m_frequency = (double)freq.QuadPart;
#endif
reset();
}
~BenchTimer() {}
inline void reset(void) {m_best = 1e6;}
inline void start(void) {m_start = getTime();}
inline void stop(void)
{
m_best = std::min(m_best, getTime() - m_start);
}
/** Return the best elapsed time in seconds.
*/
inline double value(void)
{
return m_best;
}
#ifdef WIN32
inline double getTime(void)
#else
static inline double getTime(void)
#endif
{
#ifdef WIN32
LARGE_INTEGER query_ticks;
QueryPerformanceCounter(&query_ticks);
return query_ticks.QuadPart/m_frequency;
#else
struct timeval tv;
struct timezone tz;
gettimeofday(&tv, &tz);
return (double)tv.tv_sec + 1.e-6 * (double)tv.tv_usec;
#endif
}
protected:
#ifdef WIN32
double m_frequency;
#endif
double m_best, m_start;
};
}
#endif // EIGEN_BENCH_TIMER_H