This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
[patch, fortran] PR34533 - dtime vs. etime
- From: Daniel Franke <franke dot daniel at gmail dot com>
- To: fortran at gcc dot gnu dot org
- Cc: gcc-patches at gcc dot gnu dot org, FX Coudert <fxcoudert at gmail dot com>
- Date: Fri, 21 Dec 2007 10:32:08 +0100
- Subject: [patch, fortran] PR34533 - dtime vs. etime
Hi all.
This patch fixes an oversight with ETIME/DTIME. While ETIME reports the
ressource usage since invokation of the application, DTIME is supposed to
give the ressource usage since the last invokation of DTIME. Up until now,
DTIME was an alias of ETIME.
The library implementation of DTIME uses a mutex to ensure data integregrity
if used with multiple threads, e.g. OpenMP. If no time-source is available,
DTIME returns -1 for each of its output values for each invokation.
Further, I took the opportunity to merge similar codes used dor CPU_TIME and
ETIME into a single function which now can be used by all three intrinsics,
CPU_TIME, DTIME and ETIME. This also implies that we now can provide a
working implementation of DTIME/ETIME for mingw.
FX, would you be so kind to test these functions there? :)
:ADDPATCH fortran:
gcc/fortran:
2007-12-21 Daniel Franke <franke.daniel@gmail.com>
* intrinsic.h (gfc_check_etime): Renamed to ...
(gfc_check_dtime_etime): ... this.
(gfc_check_etime_sub): Renamed to ...
(gfc_check_dtime_etime_sub): ... this.
(gfc_resolve_dtime_sub): New prototype.
* check.c (gfc_check_etime): Renamed to ...
(gfc_check_dtime_etime): ... this.
(gfc_check_etime_sub): Renamed to ...
(gfc_check_dtime_etime_sub): ... this.
* iresolve.c (gfc_resolve_dtime_sub): New implementation.
* intrinsic.c (add_functions): Removed alias from ETIME to DTIME,
added stand-alone intrinsic DTIME.
(add_subroutines): Adjusted check and resolve function names for
DTIME and ETIME.
* trans-intrinsic.c (gfc_conv_intrinsic_function): Added DTIME
to known functions in switch.
* intrinsic.texi (DTIME): Added paragraph about thread-safety,
fixed return value section.
(CPU_TIME): Clarified intent and added implementation notes.
libgfortran:
2007-12-21 Daniel Franke <franke.daniel@gmail.com>
* intrinsics/cpu_time.c: Moved code commonly usable for CPU_TIME,
DTIME and ETIME to ...
* intrinsics/time_1.h: ... here.
* intrinsics/dtime.c: New file.
* intrinsics/etime.c: Newly implemented using the common
time-aquisition function from time_1.h.
* gfortran.map (_gfortran_dtime, _gfortran_dtime_sub): New.
* Makefile.am: Added new file.
* Makefile.in: Regenerated.
* configure: Regenerated.
I'm not sure that I got all the various macros right, this might be a source
of easily-fixable regressions on some platforms ...
The patch does not contain the regenerated files as I currently do not have
the appropriate version of autoconf available.
Bootstrapped and regression tested on i686-pc-linux-gnu. Ok for trunk?
Regards
Daniel
Index: fortran/intrinsic.c
===================================================================
--- fortran/intrinsic.c (revision 131109)
+++ fortran/intrinsic.c (working copy)
@@ -1360,11 +1360,15 @@ add_functions (void)
make_generic ("erfc", GFC_ISYM_ERFC, GFC_STD_GNU);
/* G77 compatibility */
- add_sym_1 ("etime", GFC_ISYM_ETIME, NO_CLASS, ACTUAL_NO, BT_REAL, 4, GFC_STD_GNU,
- gfc_check_etime, NULL, NULL,
+ add_sym_1 ("dtime", GFC_ISYM_DTIME, NO_CLASS, ACTUAL_NO, BT_REAL, 4, GFC_STD_GNU,
+ gfc_check_dtime_etime, NULL, NULL,
x, BT_REAL, 4, REQUIRED);
- make_alias ("dtime", GFC_STD_GNU);
+ make_generic ("dtime", GFC_ISYM_DTIME, GFC_STD_GNU);
+
+ add_sym_1 ("etime", GFC_ISYM_ETIME, NO_CLASS, ACTUAL_NO, BT_REAL, 4, GFC_STD_GNU,
+ gfc_check_dtime_etime, NULL, NULL,
+ x, BT_REAL, 4, REQUIRED);
make_generic ("etime", GFC_ISYM_ETIME, GFC_STD_GNU);
@@ -2437,11 +2441,11 @@ add_subroutines (void)
/* More G77 compatibility garbage. */
add_sym_2s ("etime", GFC_ISYM_ETIME, NO_CLASS, BT_UNKNOWN, 0, GFC_STD_GNU,
- gfc_check_etime_sub, NULL, gfc_resolve_etime_sub,
+ gfc_check_dtime_etime_sub, NULL, gfc_resolve_etime_sub,
vl, BT_REAL, 4, REQUIRED, tm, BT_REAL, 4, REQUIRED);
add_sym_2s ("dtime", GFC_ISYM_DTIME, NO_CLASS, BT_UNKNOWN, 0, GFC_STD_GNU,
- gfc_check_etime_sub, NULL, gfc_resolve_etime_sub,
+ gfc_check_dtime_etime_sub, NULL, gfc_resolve_dtime_sub,
vl, BT_REAL, 4, REQUIRED, tm, BT_REAL, 4, REQUIRED);
add_sym_1s ("fdate", GFC_ISYM_FDATE, NO_CLASS, BT_UNKNOWN, 0, GFC_STD_GNU,
Index: fortran/intrinsic.h
===================================================================
--- fortran/intrinsic.h (revision 131109)
+++ fortran/intrinsic.h (working copy)
@@ -55,7 +55,7 @@ try gfc_check_digits (gfc_expr *);
try gfc_check_dot_product (gfc_expr *, gfc_expr *);
try gfc_check_dprod (gfc_expr *, gfc_expr *);
try gfc_check_eoshift (gfc_expr *, gfc_expr *, gfc_expr *, gfc_expr *);
-try gfc_check_etime (gfc_expr *);
+try gfc_check_dtime_etime (gfc_expr *);
try gfc_check_fgetputc (gfc_expr *, gfc_expr *);
try gfc_check_fgetput (gfc_expr *);
try gfc_check_fstat (gfc_expr *, gfc_expr *);
@@ -165,7 +165,7 @@ try gfc_check_mvbits (gfc_expr *, gfc_ex
gfc_expr *);
try gfc_check_random_number (gfc_expr *);
try gfc_check_random_seed (gfc_expr *, gfc_expr *, gfc_expr *);
-try gfc_check_etime_sub (gfc_expr *, gfc_expr *);
+try gfc_check_dtime_etime_sub (gfc_expr *, gfc_expr *);
try gfc_check_fgetputc_sub (gfc_expr *, gfc_expr *, gfc_expr *);
try gfc_check_fgetput_sub (gfc_expr *, gfc_expr *);
try gfc_check_fseek_sub (gfc_expr *, gfc_expr *, gfc_expr *, gfc_expr *);
@@ -345,6 +345,7 @@ void gfc_resolve_dble (gfc_expr *, gfc_e
void gfc_resolve_dim (gfc_expr *, gfc_expr *, gfc_expr *);
void gfc_resolve_dot_product (gfc_expr *, gfc_expr *, gfc_expr *);
void gfc_resolve_dprod (gfc_expr *, gfc_expr *, gfc_expr *);
+void gfc_resolve_dtime_sub (gfc_code *);
void gfc_resolve_eoshift (gfc_expr *, gfc_expr *, gfc_expr *, gfc_expr *,
gfc_expr *);
void gfc_resolve_etime_sub (gfc_code *);
Index: fortran/iresolve.c
===================================================================
--- fortran/iresolve.c (revision 131109)
+++ fortran/iresolve.c (working copy)
@@ -2676,7 +2676,15 @@ gfc_resolve_symlnk_sub (gfc_code *c)
}
-/* G77 compatibility subroutines etime() and dtime(). */
+/* G77 compatibility subroutines dtime() and etime(). */
+
+void
+gfc_resolve_dtime_sub (gfc_code *c)
+{
+ const char *name;
+ name = gfc_get_string (PREFIX ("dtime_sub"));
+ c->resolved_sym = gfc_get_intrinsic_sub_symbol (name);
+}
void
gfc_resolve_etime_sub (gfc_code *c)
Index: fortran/check.c
===================================================================
--- fortran/check.c (revision 131109)
+++ fortran/check.c (working copy)
@@ -3227,7 +3227,7 @@ gfc_check_ctime_sub (gfc_expr *time, gfc
try
-gfc_check_etime (gfc_expr *x)
+gfc_check_dtime_etime (gfc_expr *x)
{
if (array_check (x, 0) == FAILURE)
return FAILURE;
@@ -3249,7 +3249,7 @@ gfc_check_etime (gfc_expr *x)
try
-gfc_check_etime_sub (gfc_expr *values, gfc_expr *time)
+gfc_check_dtime_etime_sub (gfc_expr *values, gfc_expr *time)
{
if (array_check (values, 0) == FAILURE)
return FAILURE;
Index: fortran/trans-intrinsic.c
===================================================================
--- fortran/trans-intrinsic.c (revision 131109)
+++ fortran/trans-intrinsic.c (working copy)
@@ -4097,6 +4097,7 @@ gfc_conv_intrinsic_function (gfc_se * se
case GFC_ISYM_ACCESS:
case GFC_ISYM_CHDIR:
case GFC_ISYM_CHMOD:
+ case GFC_ISYM_DTIME:
case GFC_ISYM_ETIME:
case GFC_ISYM_FGET:
case GFC_ISYM_FGETC:
Index: fortran/intrinsic.texi
===================================================================
--- fortran/intrinsic.texi (revision 131109)
+++ fortran/intrinsic.texi (working copy)
@@ -2717,6 +2717,16 @@ Returns a @code{REAL(*)} value represent
seconds. This is useful for testing segments of code to determine
execution time.
+If a time source is available, time will be reported with microsecond
+resolution. If no time source is available, @var{TIME} is set to
+@code{-1.0}.
+
+Note that @var{TIME} may contain a, system depenent, arbitrary offset
+and may not start with @code{0.0}. For @code{CPU_TIME}, the absolute
+value is meaningless, only differences between subsequent calls to
+this subroutine, as shown in the example below, should be used.
+
+
@item @emph{Standard}:
F95 and later
@@ -3321,6 +3331,10 @@ sufficiently small limits that overflows
become, negative, or numerically less than previous values, during a single
run of the compiled program.
+Please note, that this implementation is thread safe if used within OpenMP
+directives, i. e. its state will be consistent while called from multiple
+threads.
+
This intrinsic is provided in both subroutine and function forms; however,
only one form can be used in any given program unit.
@@ -3351,7 +3365,8 @@ Subroutine, function
@end multitable
@item @emph{Return value}:
-Elapsed time in seconds since the start of program execution.
+Elapsed time in seconds since the last invokation or since the start of program
+execution if not called before.
@item @emph{Example}:
@smallexample
@@ -3372,6 +3387,10 @@ program test_dtime
print *, tarray(2)
end program test_dtime
@end smallexample
+
+@item @emph{See also}:
+@ref{CPU_TIME}
+
@end table
Index: Makefile.am
===================================================================
--- Makefile.am (revision 131020)
+++ Makefile.am (working copy)
@@ -60,6 +60,7 @@ intrinsics/cpu_time.c \
intrinsics/cshift0.c \
intrinsics/ctime.c \
intrinsics/date_and_time.c \
+intrinsics/dtime.c \
intrinsics/env.c \
intrinsics/eoshift0.c \
intrinsics/eoshift2.c \
Index: gfortran.map
===================================================================
--- gfortran.map (revision 131020)
+++ gfortran.map (working copy)
@@ -58,6 +58,8 @@ GFORTRAN_1.0 {
_gfortran_ctime;
_gfortran_ctime_sub;
_gfortran_date_and_time;
+ _gfortran_dtime;
+ _gfortran_dtime_sub;
_gfortran_eoshift0_1;
_gfortran_eoshift0_1_char;
_gfortran_eoshift0_2;
Index: intrinsics/dtime.c
===================================================================
--- intrinsics/dtime.c (revision 0)
+++ intrinsics/dtime.c (revision 0)
@@ -0,0 +1,86 @@
+/* Implementation of the dtime intrinsic.
+ Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
+
+This file is part of the GNU Fortran 95 runtime library (libgfortran).
+
+Libgfortran is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public
+License as published by the Free Software Foundation; either
+version 2 of the License, or (at your option) any later version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file. (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+Libgfortran 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 General Public
+License along with libgfortran; see the file COPYING. If not,
+write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA. */
+
+#include "libgfortran.h"
+#include "time_1.h"
+#include <gthr.h>
+
+#ifdef __GTHREAD_MUTEX_INIT
+static __gthread_mutex_t dtime_update_lock = __GTHREAD_MUTEX_INIT;
+#else
+static __gthread_mutex_t dtime_update_lock;
+#endif
+
+extern void dtime_sub (gfc_array_r4 *t, GFC_REAL_4 *result);
+iexport_proto(dtime_sub);
+
+void
+dtime_sub (gfc_array_r4 *t, GFC_REAL_4 *result)
+{
+ static GFC_REAL_4 tu = 0.0, ts = 0.0, tt = 0.0;
+ GFC_REAL_4 *tp;
+ long user_sec, user_usec, system_sec, system_usec;
+
+ if (((t->dim[0].ubound + 1 - t->dim[0].lbound)) < 2)
+ runtime_error ("Insufficient number of elements in TARRAY.");
+
+ __gthread_mutex_lock (&dtime_update_lock);
+ if (__time_1 (&user_sec, &user_usec, &system_sec, &system_usec) == 0)
+ {
+ tu = (GFC_REAL_4)(user_sec + 1.e-6 * user_usec) - tu;
+ ts = (GFC_REAL_4)(system_sec + 1.e-6 * system_usec) - ts;
+ tt = tu + ts;
+ }
+ else
+ {
+ tu = (GFC_REAL_4)-1.0;
+ ts = (GFC_REAL_4)-1.0;
+ tt = (GFC_REAL_4)-1.0;
+ }
+
+ tp = t->data;
+
+ *tp = tu;
+ tp += t->dim[0].stride;
+ *tp = ts;
+ *result = tt;
+ __gthread_mutex_unlock (&dtime_update_lock);
+}
+iexport(dtime_sub);
+
+extern GFC_REAL_4 dtime (gfc_array_r4 *t);
+export_proto(dtime);
+
+GFC_REAL_4
+dtime (gfc_array_r4 *t)
+{
+ GFC_REAL_4 val;
+ dtime_sub (t, &val);
+ return val;
+}
Index: intrinsics/etime.c
===================================================================
--- intrinsics/etime.c (revision 131020)
+++ intrinsics/etime.c (working copy)
@@ -29,11 +29,7 @@ write to the Free Software Foundation, I
Boston, MA 02110-1301, USA. */
#include "libgfortran.h"
-
-#if defined (HAVE_SYS_TIME_H) && defined (HAVE_SYS_RESOURCE_H)
-#include <sys/time.h>
-#include <sys/resource.h>
-#endif
+#include "time_1.h"
extern void etime_sub (gfc_array_r4 *t, GFC_REAL_4 *result);
iexport_proto(etime_sub);
@@ -42,30 +38,23 @@ void
etime_sub (gfc_array_r4 *t, GFC_REAL_4 *result)
{
GFC_REAL_4 tu, ts, tt, *tp;
+ long user_sec, user_usec, system_sec, system_usec;
-#if defined(HAVE_SYS_TIME_H) && defined(HAVE_SYS_RESOURCE_H)
- struct rusage rt;
+ if (((t->dim[0].ubound + 1 - t->dim[0].lbound)) < 2)
+ runtime_error ("Insufficient number of elements in TARRAY.");
- if (getrusage(RUSAGE_SELF, &rt) == 0)
+ if (__time_1 (&user_sec, &user_usec, &system_sec, &system_usec) == 0)
{
- tu = (GFC_REAL_4)(rt.ru_utime.tv_sec + 1.e-6 * rt.ru_utime.tv_usec);
- ts = (GFC_REAL_4)(rt.ru_stime.tv_sec + 1.e-6 * rt.ru_stime.tv_usec);
+ tu = (GFC_REAL_4)(user_sec + 1.e-6 * user_usec);
+ ts = (GFC_REAL_4)(system_sec + 1.e-6 * system_usec);
tt = tu + ts;
}
else
{
- tu = -1.;
- ts = -1.;
- tt = -1.;
+ tu = (GFC_REAL_4)-1.0;
+ ts = (GFC_REAL_4)-1.0;
+ tt = (GFC_REAL_4)-1.0;
}
-#else
- tu = -1.;
- ts = -1.;
- tt = -1.;
-#endif
-
- if (((t->dim[0].ubound + 1 - t->dim[0].lbound)) < 2)
- runtime_error ("Insufficient number of elements in TARRAY.");
tp = t->data;
Index: intrinsics/cpu_time.c
===================================================================
--- intrinsics/cpu_time.c (revision 131020)
+++ intrinsics/cpu_time.c (working copy)
@@ -28,37 +28,11 @@ write to the Free Software Foundation, I
Boston, MA 02110-1301, USA. */
#include "libgfortran.h"
-
-#ifdef HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-
-/* The CPU_TIME intrinsic to "compare different algorithms on the same
- computer or discover which parts are the most expensive", so we
- need a way to get the CPU time with the finest resolution possible.
- We can only be accurate up to microseconds.
-
- As usual with UNIX systems, unfortunately no single way is
- available for all systems. */
-
-#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
+#include "time_1.h"
/* The most accurate way to get the CPU time is getrusage ().
If we have times(), that's good enough, too. */
-#if defined (HAVE_GETRUSAGE) && defined (HAVE_SYS_RESOURCE_H)
-# include <sys/resource.h>
-#else
+#if !defined (HAVE_GETRUSAGE) || !defined (HAVE_SYS_RESOURCE_H)
/* For times(), we _must_ know the number of clock ticks per second. */
# if defined (HAVE_TIMES) && (defined (HZ) || defined (_SC_CLK_TCK) || defined (CLK_TCK))
# ifdef HAVE_SYS_PARAM_H
@@ -75,65 +49,18 @@ Boston, MA 02110-1301, USA. */
# endif
# endif
# endif /* HAVE_TIMES etc. */
-#endif /* HAVE_GETRUSAGE && HAVE_SYS_RESOURCE_H */
-
-#if defined (__GNUC__) && (__GNUC__ >= 3)
-# define ATTRIBUTE_ALWAYS_INLINE __attribute__ ((__always_inline__))
-#else
-# define ATTRIBUTE_ALWAYS_INLINE
-#endif
+#endif /* !HAVE_GETRUSAGE || !HAVE_SYS_RESOURCE_H */
static inline void __cpu_time_1 (long *, long *) ATTRIBUTE_ALWAYS_INLINE;
-/* Helper function for the actual implementation of the CPU_TIME
- intrinsic. Returns a CPU time in microseconds or -1 if no CPU time
- could be computed. */
-
-#ifdef __MINGW32__
-
-#define WIN32_LEAN_AND_MEAN
-#include <windows.h>
-
-static void
-__cpu_time_1 (long *sec, long *usec)
-{
- union {
- FILETIME ft;
- unsigned long long ulltime;
- } kernel_time, user_time;
-
- FILETIME unused1, unused2;
- unsigned long long total_time;
-
- /* No support for Win9x. The high order bit of the DWORD
- returned by GetVersion is 0 for NT and higher. */
- if (GetVersion () >= 0x80000000)
- {
- *sec = -1;
- *usec = 0;
- return;
- }
-
- /* The FILETIME structs filled in by GetProcessTimes represent
- time in 100 nanosecond units. */
- GetProcessTimes (GetCurrentProcess (), &unused1, &unused2,
- &kernel_time.ft, &user_time.ft);
-
- total_time = (kernel_time.ulltime + user_time.ulltime)/10;
- *sec = total_time / 1000000;
- *usec = total_time % 1000000;
-}
-
-#else
-
static inline void
__cpu_time_1 (long *sec, long *usec)
{
-#if defined (HAVE_GETRUSAGE) && defined (HAVE_SYS_RESOURCE_H)
- struct rusage usage;
- getrusage (0, &usage);
- *sec = usage.ru_utime.tv_sec + usage.ru_stime.tv_sec;
- *usec = usage.ru_utime.tv_usec + usage.ru_stime.tv_usec;
+#if defined(__MINGW32__) || defined (HAVE_GETRUSAGE) && defined (HAVE_SYS_RESOURCE_H)
+ long user_sec, user_usec, system_sec, system_usec;
+ __time_1 (&user_sec, &user_usec, &system_sec, &system_usec);
+ *sec = user_sec + system_sec;
+ *usec = user_usec + system_usec;
#else /* ! HAVE_GETRUSAGE || ! HAVE_SYS_RESOURCE_H */
#ifdef HAVE_TIMES
struct tms buf;
@@ -145,10 +72,9 @@ __cpu_time_1 (long *sec, long *usec)
*sec = -1;
*usec = 0;
#endif /* HAVE_TIMES */
-#endif /* HAVE_GETRUSAGE */
+#endif /* __MINGW32__ || HAVE_GETRUSAGE */
}
-#endif
extern void cpu_time_4 (GFC_REAL_4 *);
iexport_proto(cpu_time_4);
Index: intrinsics/time_1.h
===================================================================
--- intrinsics/time_1.h (revision 0)
+++ intrinsics/time_1.h (revision 0)
@@ -0,0 +1,142 @@
+/* Implementation of the CPU_TIME intrinsic.
+ Copyright (C) 2003, 2007 Free Software Foundation, Inc.
+
+This file is part of the GNU Fortran 95 runtime library (libgfortran).
+
+Libgfortran is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public
+License as published by the Free Software Foundation; either
+version 2 of the License, or (at your option) any later version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file. (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+Libgfortran 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 General Public
+License along with libgfortran; see the file COPYING. If not,
+write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA. */
+
+#ifndef LIBGFORTRAN_TIME_H
+#define LIBGFORTRAN_TIME_H
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+/* The time related intrinsics (DTIME, ETIME, CPU_TIME) to "compare
+ different algorithms on the same computer or discover which parts
+ are the most expensive", need a way to get the CPU time with the
+ finest resolution possible. We can only be accurate up to
+ microseconds.
+
+ As usual with UNIX systems, unfortunately no single way is
+ available for all systems. */
+
+#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
+
+/* The most accurate way to get the CPU time is getrusage (). */
+#if defined (HAVE_GETRUSAGE) && defined (HAVE_SYS_RESOURCE_H)
+# include <sys/resource.h>
+#endif /* HAVE_GETRUSAGE && HAVE_SYS_RESOURCE_H */
+
+#if defined (__GNUC__) && (__GNUC__ >= 3)
+# define ATTRIBUTE_ALWAYS_INLINE __attribute__ ((__always_inline__))
+#else
+# define ATTRIBUTE_ALWAYS_INLINE
+#endif
+
+static inline int __time_1 (long *, long *, long *, long *) ATTRIBUTE_ALWAYS_INLINE;
+
+/* Helper function for the actual implementation of the DTIME, ETIME and
+ CPU_TIME intrinsics. Returns a CPU time in microseconds or -1 if no
+ CPU time could be computed. */
+
+#ifdef __MINGW32__
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+static int
+__time_1 (long *user_sec, long *user_usec, long *system_sec, long *system_usec)
+{
+ union {
+ FILETIME ft;
+ unsigned long long ulltime;
+ } kernel_time, user_time;
+
+ FILETIME unused1, unused2;
+ unsigned long long total_time;
+
+ /* No support for Win9x. The high order bit of the DWORD
+ returned by GetVersion is 0 for NT and higher. */
+ if (GetVersion () >= 0x80000000)
+ {
+ *user_sec = *system_sec = 0;
+ *user_usec = *system_usec = 0;
+ return -1;
+ }
+
+ /* The FILETIME structs filled in by GetProcessTimes represent
+ time in 100 nanosecond units. */
+ GetProcessTimes (GetCurrentProcess (), &unused1, &unused2,
+ &kernel_time.ft, &user_time.ft);
+
+ *user_sec = user_time.ulltime / 10000000;
+ *user_usec = user_time.ulltime % 10000000;
+
+ *system_sec = kernel_time.ulltime / 10000000;
+ *system_usec = kernel_time.ulltime % 10000000;
+ return 0;
+}
+
+#else
+
+static inline int
+__time_1 (long *user_sec, long *user_usec, long *system_sec, long *system_usec)
+{
+#if defined (HAVE_GETRUSAGE) && defined (HAVE_SYS_RESOURCE_H)
+ struct rusage usage;
+ getrusage (0, &usage);
+
+ *user_sec = usage.ru_utime.tv_sec;
+ *user_usec = usage.ru_utime.tv_usec;
+ *system_sec = usage.ru_stime.tv_sec;
+ *system_usec = usage.ru_stime.tv_usec;
+ return 0;
+
+#else /* ! HAVE_GETRUSAGE || ! HAVE_SYS_RESOURCE_H */
+
+ /* We have nothing to go on. Return -1. */
+ *user_sec = *system_sec = 0;
+ *user_usec = *system_usec = 0;
+ return -1;
+
+#endif
+}
+
+#endif
+
+
+#endif /* LIBGFORTRAN_TIME_H */