/usr/include/libint2/timer.h is in libint2-dev 2.1.0~beta2-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 | /*
* This file is a part of Libint.
* Copyright (C) 2004-2014 Edward F. Valeev
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Library General Public License, version 2,
* as published by the Free Software Foundation.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this program. If not, see http://www.gnu.org/licenses/.
*
*/
#ifndef _libint2_src_lib_libint_timer_h_
#define _libint2_src_lib_libint_timer_h_
#if __cplusplus > 199711L
#include <chrono>
namespace libint2 {
/// Timers aggregates \c N C++11 "timers"; used to high-resolution profile stages of integral computation
/// @tparam N the number of timers
/// @note member functions are not reentrant, use one Timers object per thread
template <size_t N>
class Timers {
public:
typedef std::chrono::duration<double> dur_t;
typedef std::chrono::high_resolution_clock clock_t;
typedef std::chrono::time_point<clock_t> time_point_t;
Timers() {
clear();
set_now_overhead(0);
}
/// returns the current time point
static time_point_t now() {
return clock_t::now();
}
/// use this to report the overhead of now() call; if set, the reported timings will be adjusted for this overhead
/// @note this is clearly compiler and system dependent, please measure carefully (turn off turboboost, etc.)
/// using src/bin/profile/chrono.cc
void set_now_overhead(size_t ns) {
overhead_ = std::chrono::nanoseconds(ns);
}
/// starts timer \c t
void start(size_t t) {
tstart_[t] = now();
}
/// stops timer \c t
/// @return the duration, corrected for overhead, elapsed since the last call to \c start(t)
dur_t stop(size_t t) {
const auto tstop = now();
const dur_t result = (tstop - tstart_[t]) - overhead_;
timers_[t] += result;
return result;
}
/// reads value (in seconds) of timer \c t , converted to \c double
double read(size_t t) const {
return timers_[t].count();
}
/// resets timers to zero
void clear() {
for(auto t=0; t!=ntimers; ++t) {
timers_[t] = dur_t::zero();
tstart_[t] = time_point_t();
}
}
private:
constexpr static size_t ntimers = N;
dur_t timers_[ntimers];
time_point_t tstart_[ntimers];
dur_t overhead_; // the duration of now() call ... use this to automatically adjust reported timings is you need fine-grained timing
};
} // namespace libint2
#endif // C++11 or later
#endif // header guard
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