/osprey/libu/util/timef.c

/*
 * Copyright 2002, 2003, 2004 PathScale, Inc.  All Rights Reserved.
 */

/*

  Copyright (C) 2000, 2001 Silicon Graphics, Inc.  All Rights Reserved.

  This program is free software; you can redistribute it and/or modify it
  under the terms of version 2.1 of the GNU Lesser General Public License 
  as published by the Free Software Foundation.

  This program is distributed in the hope that it would be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  

  Further, this software is distributed without any warranty that it is
  free of the rightful claim of any third person regarding infringement 
  or the like.  Any license provided herein, whether implied or 
  otherwise, applies only to this software file.  Patent licenses, if
  any, provided herein do not apply to combinations of this program with 
  other software, or any other product whatsoever.  

  You should have received a copy of the GNU Lesser General Public 
  License along with this program; if not, write the Free Software 
  Foundation, Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, 
  USA.

  Contact information:  Silicon Graphics, Inc., 1600 Amphitheatre Pky,
  Mountain View, CA 94043, or:

  http://www.sgi.com

  For further information regarding this notice, see:

  http://oss.sgi.com/projects/GenInfo/NoticeExplan

*/


#pragma ident "@(#) libu/util/timef.c	92.1	07/07/99 13:18:33"

#include <fortran.h>
#include <unistd.h>
#include <sys/time.h>
/* In Linux <sys/time.h> this is ifdef'ed out */
#if defined(KEY) && ! defined(BUILD_OS_DARWIN)
struct timezone
  {
    int tz_minuteswest;		/* Minutes west of GMT.  */
    int tz_dsttime;		/* Nonzero if DST is ever in effect.  */
  };
#endif

#ifndef	_WORD32
typedef long int64;
#else
typedef long long int64;
#endif

#ifdef _UNICOS
double		_sec_per_clock;		/* Seconds per clock tick */
#define MSECPERCLK ( _sec_per_clock * 1000.0 )
#elif  ! defined(__mips)
#define MSECPERCLK ( (double).001 )	/* gettimeofday has 1000000 ticks/sec */
#endif

/*
 *	TIMEF returns the elapsed wall-clock time in floating-point 
 *	milliseconds since the first call to TIMEF.  
 *
 *	NOTE (YMP systems):
 *
 *		Because the real-time clock value may exceed 48 bits, the 
 *		floating-point conversion done here often loses some precision.
 * 		The greatest possible error in the value returned by TIMEF is
 *		N seconds, where N is approximated by:
 *
 *		N = (machine clock period time in nanoseconds) * (1.4E-6)
 *
 *	Called from Fortran:
 *
 *		REAL TIMEF
 *
 *		x = TIMEF();
 *	or	CALL TIMEF(x)		UNICOS systems only
 */

#ifndef	__mips
_f_real
#ifdef	_UNICOS
TIMEF(_f_real *time)
#else
timef_(void)
#endif
{
	static int64	initial_rt = -1; /* Clock value from initial call */
	int64		rt, rtdif;
	double		retval;

#ifdef	_UNICOS
        if (_sec_per_clock == 0.0)
                _sec_per_clock = 1.0 / (double) sysconf(_SC_CLK_TCK);

	rt	= _rtc();
#else
	{
        struct timeval  buf;
	struct timezone	buf2;
	(void) gettimeofday (&buf, &buf2);
        rt = (long long)buf.tv_sec * 1000000LL + buf.tv_usec;
	}
#endif

	if (initial_rt < 0) {
		initial_rt	= rt;
		rtdif		= 0;
		/*
		 * force rtdif to 0 to prevent anomalies due to possible
		 * race conditions between 2 or more tasks calling TIMEF
		 * concurrently on the initial call.
		 */
	}
	else
		rtdif		= rt - initial_rt;

/*
 *	On pre-7.0 UNICOS CX/CEA systems and on all CRAY-2 systems the 
 *	real-time hardware clock is set to 0 on reboot.  If a restarted 
 *	process had called TIMEF before the system was brought down 
 *	and then after reboot, a negative difference in the real-time 
 *	clock value would be observed.  To minimize the impact of
 *	wrong timings being returned, we return 0 when this situation is 
 *	detected.
 */
	if (rtdif < 0) {
		initial_rt	= rt;
		rtdif		= 0;
	}

	retval	= (double) rtdif * MSECPERCLK;

#ifdef	_UNICOS
	if (_numargs() > 0)
		*time	= (_f_real) retval;
#endif

	return( (_f_real) retval);
}

#ifdef KEY /* Bug 12813 */
_f_real8
_Timef(void)
{
	static int64	initial_rt = -1; /* Clock value from initial call */
	int64		rt, rtdif;
	double		retval;

	{
        struct timeval  buf;
	struct timezone	buf2;
	(void) gettimeofday (&buf, &buf2);
        rt = (long long)buf.tv_sec * 1000000LL + buf.tv_usec;
	}

	if (initial_rt < 0) {
		initial_rt	= rt;
		rtdif		= 0;
		/*
		 * force rtdif to 0 to prevent anomalies due to possible
		 * race conditions between 2 or more tasks calling TIMEF
		 * concurrently on the initial call.
		 */
	}
	else
		rtdif		= rt - initial_rt;

/*
 *	On pre-7.0 UNICOS CX/CEA systems and on all CRAY-2 systems the 
 *	real-time hardware clock is set to 0 on reboot.  If a restarted 
 *	process had called TIMEF before the system was brought down 
 *	and then after reboot, a negative difference in the real-time 
 *	clock value would be observed.  To minimize the impact of
 *	wrong timings being returned, we return 0 when this situation is 
 *	detected.
 */
	if (rtdif < 0) {
		initial_rt	= rt;
		rtdif		= 0;
	}

	return (_f_real8) rtdif * MSECPERCLK;
}
#endif	/* KEY Bug 12813 */
#endif	/* ! __mips */

/*
 *	MIPS version is different from Sparc version.
 */
#ifdef	__mips 

extern double _nowrap_cycles_per_sec;

_f_real8
timef_(void)
{
	static int64	initial_rt = -1; /* Clock value from initial call */
	int64		rt, rtdif;
        static double msec_per_cycle;    /* reciprocal so we can multiply */

        if (msec_per_cycle == 0.0) {
                _init_hw_clock();
                msec_per_cycle = 1000.0 / _nowrap_cycles_per_sec;
        }

	rt = _sysclock_nowrap();

	if (initial_rt < 0) {
		initial_rt	= rt;
		rtdif		= 0;
		/*
		 * force rtdif to 0 to prevent anomalies due to possible
		 * race conditions between 2 or more tasks calling TIMEF
		 * concurrently on the initial call.
		 */
	}
	else
		rtdif		= rt - initial_rt;

	return  (_f_real8)rtdif * msec_per_cycle;
}

#endif	/* __mips */