gcc/fortran:

2007-12-25  Daniel Franke  <franke.daniel@gmail.com>

	PR fortran/34533
	* 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:
2007-12-25  Daniel Franke  <franke.daniel@gmail.com>

	PR fortran/34533
	* 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.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@131168 138bc75d-0d04-0410-961f-82ee72b054a4

7 files changed, 69 insertions, 11 deletions

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 9db44b24da5..7ffa51d1516 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,26 @@
+2007-12-25  Daniel Franke  <franke.daniel@gmail.com>
+
+	PR fortran/34533
+	* 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.
+
 2007-12-23  Tobias Burnus  <burnus@net-b.de>
 
 	PR fortran/34421
diff --git a/gcc/fortran/check.c b/gcc/fortran/check.c
index 9cc4d8570de..ba7bcf295bd 100644
--- a/gcc/fortran/check.c
+++ b/gcc/fortran/check.c
@@ -3230,7 +3230,7 @@ gfc_check_ctime_sub (gfc_expr *time, gfc_expr *result)
 
 
 try
-gfc_check_etime (gfc_expr *x)
+gfc_check_dtime_etime (gfc_expr *x)
 {
   if (array_check (x, 0) == FAILURE)
     return FAILURE;
@@ -3252,7 +3252,7 @@ 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;
diff --git a/gcc/fortran/intrinsic.c b/gcc/fortran/intrinsic.c
index 039e2288cd6..227c5ec1c6e 100644
--- a/gcc/fortran/intrinsic.c
+++ b/gcc/fortran/intrinsic.c
@@ -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,
diff --git a/gcc/fortran/intrinsic.h b/gcc/fortran/intrinsic.h
index 59cdfb14eeb..dc544890e49 100644
--- a/gcc/fortran/intrinsic.h
+++ b/gcc/fortran/intrinsic.h
@@ -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_expr *, gfc_expr *, gfc_expr *,
 		      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_expr *);
 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 *);
diff --git a/gcc/fortran/intrinsic.texi b/gcc/fortran/intrinsic.texi
index f31ca25a11c..8b177087080 100644
--- a/gcc/fortran/intrinsic.texi
+++ b/gcc/fortran/intrinsic.texi
@@ -2717,6 +2717,16 @@ Returns a @code{REAL(*)} value representing the elapsed CPU time in
 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 dependent, 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 +3331,12 @@ sufficiently small limits that overflows (wrap around) are possible, such as
 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. However, if @code{DTIME} is called from multiple threads, the result
+is still the time since the last invocation. This may not give the intended
+results. If possible, use @code{CPU_TIME} instead.
+
 This intrinsic is provided in both subroutine and function forms; however,
 only one form can be used in any given program unit.
 
@@ -3351,7 +3367,8 @@ 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 invocation or since the start of program
+execution if not called before.
 
 @item @emph{Example}:
 @smallexample
@@ -3372,6 +3389,10 @@ program test_dtime
     print *, tarray(2)
 end program test_dtime
 @end smallexample
+
+@item @emph{See also}:
+@ref{CPU_TIME}
+
 @end table
 
 
diff --git a/gcc/fortran/iresolve.c b/gcc/fortran/iresolve.c
index cdc4ac176dd..8a09efcfcb5 100644
--- a/gcc/fortran/iresolve.c
+++ b/gcc/fortran/iresolve.c
@@ -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)
diff --git a/gcc/fortran/trans-intrinsic.c b/gcc/fortran/trans-intrinsic.c
index 63c56040eb2..c10d44a1410 100644
--- a/gcc/fortran/trans-intrinsic.c
+++ b/gcc/fortran/trans-intrinsic.c
@@ -4097,6 +4097,7 @@ gfc_conv_intrinsic_function (gfc_se * se, gfc_expr * expr)
     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: