diff options
Diffstat (limited to 'demos/spectrum/3rdparty/fftreal/stopwatch/ClockCycleCounter.cpp')
-rw-r--r-- | demos/spectrum/3rdparty/fftreal/stopwatch/ClockCycleCounter.cpp | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/demos/spectrum/3rdparty/fftreal/stopwatch/ClockCycleCounter.cpp b/demos/spectrum/3rdparty/fftreal/stopwatch/ClockCycleCounter.cpp new file mode 100644 index 0000000..fe1d424 --- /dev/null +++ b/demos/spectrum/3rdparty/fftreal/stopwatch/ClockCycleCounter.cpp @@ -0,0 +1,285 @@ +/***************************************************************************** + + ClockCycleCounter.cpp + Copyright (c) 2003 Laurent de Soras + +--- Legal stuff --- + +This library 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 2.1 of the License, or (at your option) any later version. + +This library 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 for more details. + +You should have received a copy of the GNU Lesser General Public +License along with this library; if not, write to the Free Software +Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + +*Tab=3***********************************************************************/ + + + +#if defined (_MSC_VER) + #pragma warning (1 : 4130) // "'operator' : logical operation on address of string constant" + #pragma warning (1 : 4223) // "nonstandard extension used : non-lvalue array converted to pointer" + #pragma warning (1 : 4705) // "statement has no effect" + #pragma warning (1 : 4706) // "assignment within conditional expression" + #pragma warning (4 : 4786) // "identifier was truncated to '255' characters in the debug information" + #pragma warning (4 : 4800) // "forcing value to bool 'true' or 'false' (performance warning)" + #pragma warning (4 : 4355) // "'this' : used in base member initializer list" +#endif + + + +/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/ + +#include "ClockCycleCounter.h" + +#include <cassert> + + + +namespace stopwatch +{ + + + +/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/ + + + +/* +============================================================================== +Name: ctor +Description: + The first object constructed initialise global data. This first + construction may be a bit slow. +Throws: Nothing +============================================================================== +*/ + +ClockCycleCounter::ClockCycleCounter () +: _start_time (0) +, _state (0) +, _best_score (-1) +{ + if (! _init_flag) + { + // Should be executed in this order + compute_clk_mul (); + compute_measure_time_total (); + compute_measure_time_lap (); + + // Restores object state + _start_time = 0; + _state = 0; + _best_score = -1; + + _init_flag = true; + } +} + + + +/* +============================================================================== +Name: get_time_total +Description: + Gives the time elapsed between the latest stop_lap() and start() calls. +Returns: + The duration, in clock cycles. +Throws: Nothing +============================================================================== +*/ + +Int64 ClockCycleCounter::get_time_total () const +{ + const Int64 duration = _state - _start_time; + assert (duration >= 0); + + const Int64 t = max ( + duration - _measure_time_total, + static_cast <Int64> (0) + ); + + return (t * _clk_mul); +} + + + +/* +============================================================================== +Name: get_time_best_lap +Description: + Gives the smallest time between two consecutive stop_lap() or between + the stop_lap() and start(). The value is reset by a call to start(). + Call this function only after a stop_lap(). + The time is amputed from the duration of the stop_lap() call itself. +Returns: + The smallest duration, in clock cycles. +Throws: Nothing +============================================================================== +*/ + +Int64 ClockCycleCounter::get_time_best_lap () const +{ + assert (_best_score >= 0); + + const Int64 t1 = max ( + _best_score - _measure_time_lap, + static_cast <Int64> (0) + ); + const Int64 t = min (t1, get_time_total ()); + + return (t * _clk_mul); +} + + + +/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/ + + + +/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/ + + + +#if defined (__MACOS__) + +static inline double stopwatch_ClockCycleCounter_get_time_s () +{ + const Nanoseconds ns = AbsoluteToNanoseconds (UpTime ()); + + return (ns.hi * 4294967296e-9 + ns.lo * 1e-9); +} + +#endif // __MACOS__ + + + +/* +============================================================================== +Name: compute_clk_mul +Description: + This function, only for PowerPC/MacOS computers, computes the multiplier + required to deduce clock cycles from the internal counter. +Throws: Nothing +============================================================================== +*/ + +void ClockCycleCounter::compute_clk_mul () +{ + assert (! _init_flag); + +#if defined (__MACOS__) + + long clk_speed_mhz = CurrentProcessorSpeed (); + const Int64 clk_speed = + static_cast <Int64> (clk_speed_mhz) * (1000L*1000L); + + const double start_time_s = stopwatch_ClockCycleCounter_get_time_s (); + start (); + + const double duration = 0.01; // Seconds + while (stopwatch_ClockCycleCounter_get_time_s () - start_time_s < duration) + { + continue; + } + + const double stop_time_s = stopwatch_ClockCycleCounter_get_time_s (); + stop (); + + const double diff_time_s = stop_time_s - start_time_s; + const double nbr_cycles = diff_time_s * static_cast <double> (clk_speed); + + const Int64 diff_time_c = _state - _start_time; + const double clk_mul = nbr_cycles / static_cast <double> (diff_time_c); + + _clk_mul = round_int (clk_mul); + +#endif // __MACOS__ +} + + + +void ClockCycleCounter::compute_measure_time_total () +{ + start (); + spend_time (); + + Int64 best_result = 0x7FFFFFFFL; // Should be enough + long nbr_tests = 100; + for (long cnt = 0; cnt < nbr_tests; ++cnt) + { + start (); + stop_lap (); + const Int64 duration = _state - _start_time; + best_result = min (best_result, duration); + } + + _measure_time_total = best_result; +} + + + +/* +============================================================================== +Name: compute_measure_time_lap +Description: + Computes the duration of one stop_lap() call and store it. It will be used + later to get the real duration of the measured operation (by substracting + the measurement duration). +Throws: Nothing +============================================================================== +*/ + +void ClockCycleCounter::compute_measure_time_lap () +{ + start (); + spend_time (); + + long nbr_tests = 10; + for (long cnt = 0; cnt < nbr_tests; ++cnt) + { + stop_lap (); + stop_lap (); + stop_lap (); + stop_lap (); + } + + _measure_time_lap = _best_score; +} + + + +void ClockCycleCounter::spend_time () +{ + const Int64 nbr_clocks = 500; // Number of clock cycles to spend + + const Int64 start = read_clock_counter (); + Int64 current; + + do + { + current = read_clock_counter (); + } + while ((current - start) * _clk_mul < nbr_clocks); +} + + + +Int64 ClockCycleCounter::_measure_time_total = 0; +Int64 ClockCycleCounter::_measure_time_lap = 0; +int ClockCycleCounter::_clk_mul = 1; +bool ClockCycleCounter::_init_flag = false; + + +} // namespace stopwatch + + + +/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/ |