diff mbox

[Fortran] Sync memory action delegated to OpenCoarrays

Message ID 54FE9B30.3010004@net-b.de
State New
Headers show

Commit Message

Tobias Burnus March 10, 2015, 7:20 a.m. UTC 
Hi Alessandro,

Alessandro Fanfarillo wrote:
> Thanks for the quick response. Patch built and regtested on x86_64-unknown-linux-gnu.

Actually, I also was about to send a reworked patch myself - see 
attachment. Additional changes compared to your last patch:
* Add the assembler statement to libcaf_single also for the other syncs.
* Tested also the passing of the other arguments in the test case.
* Removed the call to sync_synchronize in the compiler - leaving it 
completely to the library. (Existed for end of program, STOP and SYNC 
...; was only issued with -fcoarray=lib)

Are the changes okay from your side? Then I'd prefer my patch - and I'll 
commit it this evening.

  * * *

> Currently the stub for sync memory in single.c invokes "asm volatile
> ("" : : : "memory")" but _gfortran_caf_sync_memory is not called when
> the code is compiled with -fcoarray=single.

I misremembered that we do call __sync_synchronize for -fcoarray=single. 
As it turned out, we only call it for -fcoarray=lib - and it makes sense 
(in my opinion) to leave such calls to the library.

As you, I also added the "asm" to the library - which probably has no 
effect - except when the library and the program are both compiled with 
LTO. Still, it somehow looks more complete.


Regarding: Looks good to me - except that I prefer the additional items 
of my patch - and that the ChangeLog doesn't conform to the GCC style:
- The file names shall be relative to the change log, i.e. 
"caf/single.c" (as the ChangeLog file is in libgfortran/ChangeLog), 
similarly a "gfortran.dg/" is missing for the test case.
- There should be a single "<tab>* " before the file names, not two tabs 
and no "* ".
- After the file name, the changed symbols/function names shall be put 
in parentheses.
- The item describing the change should end with a full stop.
- The email address should be enclosed in <>.
(Often missed, but not by you: date-name-email separation is two spaces.)

Tobias

> Please let me know if I have to change the patch for -fcoarray=single.
>
>
>
> 2015-03-06 11:20 GMT-08:00 Tobias Burnus <burnus@net-b.de>:
>> Dear Alessandro,
>>
>> Alessandro Fanfarillo wrote:
>>
>> so far a "sync memory" statement is translated into a local
>> "__sync_synchronize ()".
>> The attached draft patch delegates the action for sync memory (when
>> -fcoarray=lib is used) to the external function
>> _gfortran_caf_sync_memory() implemented in the OpenCoarrays library.
>>
>>
>> Looks good to me. However, you should add a test case with 'dg-options
>> "-fdump-tree-original -fcoarray=lib"' to check that this works; cf.
>> gcc/testsuite/gfortran.dg/coarray*.f90 for examples.
>>
>> And you have to provide a stub implementation in
>> libgfortran/caf/{libcaf.h,single.c}.
>>
>> Tobias
>>
>> PS: I wonder whether it makes sense to remove the __sync_synchronize for
>> -fcoarray=single and replace it by the equivalent to "asm volatile ("" : : :
>> "memory")". It almost certainly does.

Comments

Alessandro Fanfarillo March 10, 2015, 3:29 p.m. UTC | #1 
Totally fine with me. Thanks.

2015-03-10 0:20 GMT-07:00 Tobias Burnus <burnus@net-b.de>:
> Hi Alessandro,
>
> Alessandro Fanfarillo wrote:
>>
>> Thanks for the quick response. Patch built and regtested on
>> x86_64-unknown-linux-gnu.
>
>
> Actually, I also was about to send a reworked patch myself - see attachment.
> Additional changes compared to your last patch:
> * Add the assembler statement to libcaf_single also for the other syncs.
> * Tested also the passing of the other arguments in the test case.
> * Removed the call to sync_synchronize in the compiler - leaving it
> completely to the library. (Existed for end of program, STOP and SYNC ...;
> was only issued with -fcoarray=lib)
>
> Are the changes okay from your side? Then I'd prefer my patch - and I'll
> commit it this evening.
>
>  * * *
>
>> Currently the stub for sync memory in single.c invokes "asm volatile
>> ("" : : : "memory")" but _gfortran_caf_sync_memory is not called when
>> the code is compiled with -fcoarray=single.
>
>
> I misremembered that we do call __sync_synchronize for -fcoarray=single. As
> it turned out, we only call it for -fcoarray=lib - and it makes sense (in my
> opinion) to leave such calls to the library.
>
> As you, I also added the "asm" to the library - which probably has no effect
> - except when the library and the program are both compiled with LTO. Still,
> it somehow looks more complete.
>
>
> Regarding: Looks good to me - except that I prefer the additional items of
> my patch - and that the ChangeLog doesn't conform to the GCC style:
> - The file names shall be relative to the change log, i.e. "caf/single.c"
> (as the ChangeLog file is in libgfortran/ChangeLog), similarly a
> "gfortran.dg/" is missing for the test case.
> - There should be a single "<tab>* " before the file names, not two tabs and
> no "* ".
> - After the file name, the changed symbols/function names shall be put in
> parentheses.
> - The item describing the change should end with a full stop.
> - The email address should be enclosed in <>.
> (Often missed, but not by you: date-name-email separation is two spaces.)
>
> Tobias
>
>
>> Please let me know if I have to change the patch for -fcoarray=single.
>>
>>
>>
>> 2015-03-06 11:20 GMT-08:00 Tobias Burnus <burnus@net-b.de>:
>>>
>>> Dear Alessandro,
>>>
>>> Alessandro Fanfarillo wrote:
>>>
>>> so far a "sync memory" statement is translated into a local
>>> "__sync_synchronize ()".
>>> The attached draft patch delegates the action for sync memory (when
>>> -fcoarray=lib is used) to the external function
>>> _gfortran_caf_sync_memory() implemented in the OpenCoarrays library.
>>>
>>>
>>> Looks good to me. However, you should add a test case with 'dg-options
>>> "-fdump-tree-original -fcoarray=lib"' to check that this works; cf.
>>> gcc/testsuite/gfortran.dg/coarray*.f90 for examples.
>>>
>>> And you have to provide a stub implementation in
>>> libgfortran/caf/{libcaf.h,single.c}.
>>>
>>> Tobias
>>>
>>> PS: I wonder whether it makes sense to remove the __sync_synchronize for
>>> -fcoarray=single and replace it by the equivalent to "asm volatile ("" :
>>> : :
>>> "memory")". It almost certainly does.
>
>
diff mbox

Patch

2015-03-09  Alessandro Fanfarillo  fanfarillo.gcc@gmail.com
	    Tobias Burnus  <burnus@net-b.de>

	* trans.h (caf_sync_memory): New function decl tree.
	* trans-decl.c (gfc_build_builtin_function_decls): Define it.
	(create_main_function): Don't call sync_synchronize and leave
	it to the CAF library.
	* trans-stmt.c (gfc_trans_stop): Ditto.
	(gfc_trans_sync): Ditto; add call library call for sync memory.

	* coarray_sync_memory.f90: New.

	* caf/libcaf.h (_gfortran_caf_sync_memory): New prototype.
	* caf/single.c (_gfortran_caf_sync_memory): Implement.
	(_gfortran_caf_sync_all, _gfortran_caf_sync_image): Add
	__asm__ __volatile___ ("":::"memory").

diff --git a/gcc/fortran/trans-decl.c b/gcc/fortran/trans-decl.c
index 3664824..769d487 100644
--- a/gcc/fortran/trans-decl.c
+++ b/gcc/fortran/trans-decl.c
@@ -153,6 +153,7 @@  tree gfor_fndecl_caf_get;
 tree gfor_fndecl_caf_send;
 tree gfor_fndecl_caf_sendget;
 tree gfor_fndecl_caf_sync_all;
+tree gfor_fndecl_caf_sync_memory;
 tree gfor_fndecl_caf_sync_images;
 tree gfor_fndecl_caf_error_stop;
 tree gfor_fndecl_caf_error_stop_str;
@@ -3451,6 +3452,10 @@  gfc_build_builtin_function_decls (void)
 	get_identifier (PREFIX("caf_sync_all")), ".WW", void_type_node,
 	3, pint_type, pchar_type_node, integer_type_node);
 
+      gfor_fndecl_caf_sync_memory = gfc_build_library_function_decl_with_spec (
+	get_identifier (PREFIX("caf_sync_memory")), ".WW", void_type_node,
+	3, pint_type, pchar_type_node, integer_type_node);
+
       gfor_fndecl_caf_sync_images = gfc_build_library_function_decl_with_spec (
 	get_identifier (PREFIX("caf_sync_images")), ".RRWW", void_type_node,
 	5, integer_type_node, pint_type, pint_type,
@@ -5583,12 +5588,6 @@  create_main_function (tree fndecl)
   /* Coarray: Call _gfortran_caf_finalize(void).  */
   if (flag_coarray == GFC_FCOARRAY_LIB)
     {
-      /* Per F2008, 8.5.1 END of the main program implies a
-	 SYNC MEMORY.  */
-      tmp = builtin_decl_explicit (BUILT_IN_SYNC_SYNCHRONIZE);
-      tmp = build_call_expr_loc (input_location, tmp, 0);
-      gfc_add_expr_to_block (&body, tmp);
-
       tmp = build_call_expr_loc (input_location, gfor_fndecl_caf_finalize, 0);
       gfc_add_expr_to_block (&body, tmp);
     }
diff --git a/gcc/fortran/trans-stmt.c b/gcc/fortran/trans-stmt.c
index 505f905..6450a0e 100644
--- a/gcc/fortran/trans-stmt.c
+++ b/gcc/fortran/trans-stmt.c
@@ -639,17 +639,6 @@  gfc_trans_stop (gfc_code *code, bool error_stop)
   gfc_init_se (&se, NULL);
   gfc_start_block (&se.pre);
 
-  if (flag_coarray == GFC_FCOARRAY_LIB && !error_stop)
-    {
-      /* Per F2008, 8.5.1 STOP implies a SYNC MEMORY.  */
-      tmp = builtin_decl_explicit (BUILT_IN_SYNC_SYNCHRONIZE);
-      tmp = build_call_expr_loc (input_location, tmp, 0);
-      gfc_add_expr_to_block (&se.pre, tmp);
-
-      tmp = build_call_expr_loc (input_location, gfor_fndecl_caf_finalize, 0);
-      gfc_add_expr_to_block (&se.pre, tmp);
-    }
-
   if (code->expr1 == NULL)
     {
       tmp = build_int_cst (gfc_int4_type_node, 0);
@@ -768,8 +757,7 @@  gfc_trans_sync (gfc_code *code, gfc_exec_op type)
   else
     stat = null_pointer_node;
 
-  if (code->expr3 && flag_coarray == GFC_FCOARRAY_LIB
-      && type != EXEC_SYNC_MEMORY)
+  if (code->expr3 && flag_coarray == GFC_FCOARRAY_LIB)
     {
       gcc_assert (code->expr3->expr_type == EXPR_VARIABLE);
       gfc_init_se (&argse, NULL);
@@ -778,7 +766,7 @@  gfc_trans_sync (gfc_code *code, gfc_exec_op type)
       errmsg = gfc_build_addr_expr (NULL, argse.expr);
       errmsglen = argse.string_length;
     }
-  else if (flag_coarray == GFC_FCOARRAY_LIB && type != EXEC_SYNC_MEMORY)
+  else if (flag_coarray == GFC_FCOARRAY_LIB)
     {
       errmsg = null_pointer_node;
       errmsglen = build_int_cst (integer_type_node, 0);
@@ -813,22 +801,13 @@  gfc_trans_sync (gfc_code *code, gfc_exec_op type)
 			       fold_convert (integer_type_node, images));
     }
 
-   /* Per F2008, 8.5.1, a SYNC MEMORY is implied by calling the
-      image control statements SYNC IMAGES and SYNC ALL.  */
-   if (flag_coarray == GFC_FCOARRAY_LIB)
-     {
-       tmp = builtin_decl_explicit (BUILT_IN_SYNC_SYNCHRONIZE);
-       tmp = build_call_expr_loc (input_location, tmp, 0);
-       gfc_add_expr_to_block (&se.pre, tmp);
-     }
-
-  if (flag_coarray != GFC_FCOARRAY_LIB || type == EXEC_SYNC_MEMORY)
+  if (flag_coarray != GFC_FCOARRAY_LIB)
     {
       /* Set STAT to zero.  */
       if (code->expr2)
 	gfc_add_modify (&se.pre, stat, build_int_cst (TREE_TYPE (stat), 0));
     }
-  else if (type == EXEC_SYNC_ALL)
+  else if (type == EXEC_SYNC_ALL || type == EXEC_SYNC_MEMORY)
     {
       /* SYNC ALL           =>   stat == null_pointer_node
 	 SYNC ALL(stat=s)   =>   stat has an integer type
@@ -840,8 +819,13 @@  gfc_trans_sync (gfc_code *code, gfc_exec_op type)
 	  if (TREE_TYPE (stat) == integer_type_node)
 	    stat = gfc_build_addr_expr (NULL, stat);
 
-	  tmp = build_call_expr_loc (input_location, gfor_fndecl_caf_sync_all,
-				     3, stat, errmsg, errmsglen);
+	  if(type == EXEC_SYNC_MEMORY)
+	    tmp = build_call_expr_loc (input_location, gfor_fndecl_caf_sync_memory,
+				       3, stat, errmsg, errmsglen);
+	  else
+	    tmp = build_call_expr_loc (input_location, gfor_fndecl_caf_sync_all,
+				       3, stat, errmsg, errmsglen);
+
 	  gfc_add_expr_to_block (&se.pre, tmp);
 	}
       else
diff --git a/gcc/fortran/trans.h b/gcc/fortran/trans.h
index bd1520a..3ba2f88 100644
--- a/gcc/fortran/trans.h
+++ b/gcc/fortran/trans.h
@@ -731,6 +731,7 @@  extern GTY(()) tree gfor_fndecl_caf_get;
 extern GTY(()) tree gfor_fndecl_caf_send;
 extern GTY(()) tree gfor_fndecl_caf_sendget;
 extern GTY(()) tree gfor_fndecl_caf_sync_all;
+extern GTY(()) tree gfor_fndecl_caf_sync_memory;
 extern GTY(()) tree gfor_fndecl_caf_sync_images;
 extern GTY(()) tree gfor_fndecl_caf_error_stop;
 extern GTY(()) tree gfor_fndecl_caf_error_stop_str;
diff --git a/gcc/testsuite/gfortran.dg/coarray_sync_memory.f90 b/gcc/testsuite/gfortran.dg/coarray_sync_memory.f90
new file mode 100644
index 0000000..6e1aee3
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/coarray_sync_memory.f90
@@ -0,0 +1,19 @@ 
+! { dg-do compile }
+! { dg-options "-fdump-tree-original -fcoarray=lib" }
+!
+! Coarray sync memory managed by the external library
+!
+implicit none
+integer :: stat
+character(len=42) :: msg
+sync memory
+sync memory(stat=stat)
+sync memory(errmsg=msg)
+sync memory(errmsg=msg, stat=stat)
+end
+
+! { dg-final { scan-tree-dump-times "_gfortran_caf_sync_memory \\(0B, 0B, 0\\);" 1 "original" } }
+! { dg-final { scan-tree-dump-times "_gfortran_caf_sync_memory \\(&stat, 0B, 0\\);" 1 "original" } }
+! { dg-final { scan-tree-dump-times "_gfortran_caf_sync_memory \\(0B, &&msg, 42\\);" 1 "original" } }
+! { dg-final { scan-tree-dump-times "_gfortran_caf_sync_memory \\(&stat, &&msg, 42\\);" 1 "original" } }
+! { dg-final { cleanup-tree-dump "original" } }
diff --git a/libgfortran/caf/libcaf.h b/libgfortran/caf/libcaf.h
index bd5c9c6..660bd7c 100644
--- a/libgfortran/caf/libcaf.h
+++ b/libgfortran/caf/libcaf.h
@@ -100,6 +100,7 @@  void *_gfortran_caf_register (size_t, caf_register_t, caf_token_t *, int *,
 void _gfortran_caf_deregister (caf_token_t *, int *, char *, int);
 
 void _gfortran_caf_sync_all (int *, char *, int);
+void _gfortran_caf_sync_memory (int *, char *, int);
 void _gfortran_caf_sync_images (int, int[], int *, char *, int);
 
 void _gfortran_caf_error_stop_str (const char *, int32_t)
diff --git a/libgfortran/caf/single.c b/libgfortran/caf/single.c
index 7405c91..daef281 100644
--- a/libgfortran/caf/single.c
+++ b/libgfortran/caf/single.c
@@ -162,6 +162,18 @@  _gfortran_caf_sync_all (int *stat,
 			char *errmsg __attribute__ ((unused)),
 			int errmsg_len __attribute__ ((unused)))
 {
+  __asm__ __volatile__ ("":::"memory");
+  if (stat)
+    *stat = 0;
+}
+
+
+void
+_gfortran_caf_sync_memory (int *stat,
+			   char *errmsg __attribute__ ((unused)),
+			   int errmsg_len __attribute__ ((unused)))
+{
+  __asm__ __volatile__ ("":::"memory");
   if (stat)
     *stat = 0;
 }
@@ -186,6 +198,7 @@  _gfortran_caf_sync_images (int count __attribute__ ((unused)),
       }
 #endif
 
+  __asm__ __volatile__ ("":::"memory");
   if (stat)
     *stat = 0;
 }