gcc/libiberty/getruntime.c
2021-01-04 10:26:59 +01:00

121 lines
3.0 KiB
C

/* Return time used so far, in microseconds.
Copyright (C) 1994-2021 Free Software Foundation, Inc.
This file is part of the libiberty library.
Libiberty is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
Libiberty 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with libiberty; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
Boston, MA 02110-1301, USA. */
#include "config.h"
#include "ansidecl.h"
#include "libiberty.h"
/* On some systems (such as WindISS), you must include <sys/types.h>
to get the definition of "time_t" before you include <time.h>. */
#include <sys/types.h>
/* There are several ways to get elapsed execution time; unfortunately no
single way is available for all host systems, nor are there reliable
ways to find out which way is correct for a given host. */
#ifdef TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# if HAVE_SYS_TIME_H
# include <sys/time.h>
# else
# ifdef HAVE_TIME_H
# include <time.h>
# endif
# endif
#endif
#if defined (HAVE_GETRUSAGE) && defined (HAVE_SYS_RESOURCE_H)
#include <sys/resource.h>
#endif
#ifdef HAVE_TIMES
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#include <sys/times.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
/* This is a fallback; if wrong, it will likely make obviously wrong
results. */
#ifndef CLOCKS_PER_SEC
#define CLOCKS_PER_SEC 1
#endif
#ifndef RUSAGE_SELF
#define RUSAGE_SELF 0
#endif
#ifdef _SC_CLK_TCK
#define GNU_HZ sysconf(_SC_CLK_TCK)
#else
#ifdef HZ
#define GNU_HZ HZ
#else
#ifdef CLOCKS_PER_SEC
#define GNU_HZ CLOCKS_PER_SEC
#endif
#endif
#endif
/*
@deftypefn Replacement long get_run_time (void)
Returns the time used so far, in microseconds. If possible, this is
the time used by this process, else it is the elapsed time since the
process started.
@end deftypefn
*/
long
get_run_time (void)
{
#if defined (HAVE_GETRUSAGE) && defined (HAVE_SYS_RESOURCE_H)
struct rusage rusage;
getrusage (RUSAGE_SELF, &rusage);
return (rusage.ru_utime.tv_sec * 1000000 + rusage.ru_utime.tv_usec
+ rusage.ru_stime.tv_sec * 1000000 + rusage.ru_stime.tv_usec);
#else /* ! HAVE_GETRUSAGE */
#ifdef HAVE_TIMES
struct tms tms;
times (&tms);
return (tms.tms_utime + tms.tms_stime) * (1000000 / GNU_HZ);
#else /* ! HAVE_TIMES */
/* Fall back on clock and hope it's correctly implemented. */
const long clocks_per_sec = CLOCKS_PER_SEC;
if (clocks_per_sec <= 1000000)
return clock () * (1000000 / clocks_per_sec);
else
return clock () / clocks_per_sec;
#endif /* HAVE_TIMES */
#endif /* HAVE_GETRUSAGE */
}