/*****************************************************************************

        ClockCycleCounter.hpp

        Copyright (c) 2003 Laurent de Soras

Please complete the definitions according to your compiler/architecture.

It's not a big deal if it's not possible to get the clock count...

--- 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 (stopwatch_ClockCycleCounter_CURRENT_CODEHEADER)

	#error Recursive inclusion of ClockCycleCounter code header.

#endif

#define	stopwatch_ClockCycleCounter_CURRENT_CODEHEADER

#if ! defined (stopwatch_ClockCycleCounter_CODEHEADER_INCLUDED)

#define	stopwatch_ClockCycleCounter_CODEHEADER_INCLUDED

/*\\\ INCLUDE FILES \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/

#include	"fnc.h"

#include	<climits>

namespace stopwatch

{

/*\\\ PUBLIC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/

/*

==============================================================================

Name: start

Description:

	Starts the counter.

Throws: Nothing

==============================================================================

*/

void	ClockCycleCounter::start ()

{

	_best_score = (static_cast <Int64> (1) << (sizeof (Int64) * CHAR_BIT - 2));

	const Int64		start_clock = read_clock_counter ();

	_start_time = start_clock;

	_state = start_clock - _best_score;

}

/*

==============================================================================

Name: stop_lap

Description:

	Captures the current time and updates the smallest duration between two

	consecutive calls to stop_lap() or the latest start().

	start() must have been called at least once before calling this function.

Throws: Nothing

==============================================================================

*/

void	ClockCycleCounter::stop_lap ()

{

	const Int64		end_clock = read_clock_counter ();

	_best_score = min (end_clock - _state, _best_score);

	_state = end_clock;

}

/*\\\ PROTECTED \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/

/*\\\ PRIVATE \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/

Int64	ClockCycleCounter::read_clock_counter ()

{

	register Int64		clock_cnt;

#if defined (_MSC_VER)

	__asm

	{

		lea				edi, clock_cnt

		rdtsc

		mov				[edi    ], eax

		mov				[edi + 4], edx

	}

#elif defined (__GNUC__) && defined (__i386__)

	__asm__ __volatile__ ("rdtsc" : "=A" (clock_cnt));

#elif (__MWERKS__) && defined (__POWERPC__) 

	asm

	{

	loop:

		mftbu			clock_cnt@hiword

		mftb			clock_cnt@loword

		mftbu			r5

		cmpw			clock_cnt@hiword,r5

		bne loop

	}

#endif

	return (clock_cnt);

}

}	// namespace stopwatch

#endif	// stopwatch_ClockCycleCounter_CODEHEADER_INCLUDED

#undef stopwatch_ClockCycleCounter_CURRENT_CODEHEADER

/*\\\ EOF \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*/