[Bug fortran/40973] Mark PRIVATE module functions as STATIC to faciliate optimization

[Bug fortran/40973] Mark PRIVATE module functions as STATIC to faciliate optimization

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40973

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |burnus at gcc dot gnu.org

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-04-03 15:24:35 UTC ---
See also PR 52751 for module variables.

Draft patch:

--- a/gcc/fortran/trans-decl.c
+++ b/gcc/fortran/trans-decl.c
@@ -1842,7 +1857,8 @@ build_function_decl (gfc_symbol * sym, bool global)
   DECL_EXTERNAL (fndecl) = 0;

   if (!current_function_decl
-      && !sym->attr.entry_master && !sym->attr.is_main_program)
+      && !sym->attr.entry_master && !sym->attr.is_main_program
+      && (sym->attr.access != ACCESS_PRIVATE || sym->binding_label))
     TREE_PUBLIC (fndecl) = 1;

   attributes = add_attributes_to_decl (attr, NULL_TREE);

[Bug fortran/40973] Mark PRIVATE module functions as STATIC to faciliate optimization

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40973

--- Comment #4 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-04-08 07:15:12 UTC ---
Author: burnus
Date: Sun Apr  8 07:15:01 2012
New Revision: 186223

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=186223
Log:
2012-04-08  Tobias Burnus  <burnus@net-b.de>

        PR fortran/52751
        * trans-decl.c (gfc_finish_var_decl): Don't set TREE_PUBLIC
        for PRIVATE module variables without C-binding label.

        PR fortran/40973
        * trans-decl.c (build_function_decl): Ditto for procedures.

2012-04-08  Tobias Burnus  <burnus@net-b.de>

        PR fortran/40973
        PR fortran/52751
        * gfortran.dg/public_private_module_2.f90: New.


Added:
    trunk/gcc/testsuite/gfortran.dg/public_private_module_2.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/trans-decl.c
    trunk/gcc/testsuite/ChangeLog

[Bug fortran/40973] Mark PRIVATE module functions as STATIC to faciliate optimization

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40973

Tobias Burnus <burnus at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |FIXED

--- Comment #5 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-04-08 08:07:27 UTC ---
FIXED on the 4.8 trunk.

[Bug fortran/40973] Mark PRIVATE module functions as STATIC to faciliate optimization

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40973

--- Comment #6 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-04-15 05:52:58 UTC ---
Author: burnus
Date: Sun Apr 15 05:52:51 2012
New Revision: 186464

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=186464
Log:
2012-04-14  Tobias Burnus  <burnus@net-b.de>

        PR fortran/52916
        PR fortran/40973
        * gfortran.h (symbol_attribute): Add public_used.
        * interface.c (check_sym_interfaces, check_uop_interfaces,
        gfc_check_interfaces): Set it.
        * resolve.c (resolve_typebound_procedure): Ditto.
        * trans-decl.c (build_function_decl): Use it.

2012-04-14  Tobias Burnus  <burnus@net-b.de>

        PR fortran/52916
        PR fortran/40973
        * gfortran.dg/public_private_module_3.f90: New.
        * gfortran.dg/public_private_module_4.f90: New.


Added:
    trunk/gcc/testsuite/gfortran.dg/public_private_module_3.f90
    trunk/gcc/testsuite/gfortran.dg/public_private_module_4.f90
Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/gfortran.h
    trunk/gcc/fortran/interface.c
    trunk/gcc/fortran/resolve.c
    trunk/gcc/fortran/trans-decl.c
    trunk/gcc/testsuite/ChangeLog

[Bug fortran/40973] Mark PRIVATE module functions as STATIC to faciliate optimization

[burnus at gcc dot gnu dot org]

------- Comment #2 from burnus at gcc dot gnu dot org  2010-02-20 22:08 -------
Marking it as STATIC will become difficult with SUBMODULES as one has several
.o files belonging to one common MODULE, i.e. the function shall be accessible
by all submodules, which are scattered over several .o files.

With -flto -fwhole-program it should be possible to optimize the function away
even without using STATIC.

(In reply to comment #1)
> How about this (somewhat constructed) example:

I fail to see why __m_MOD_two is needed - it is not called anywhere.

> ! interface module, file (a)
> MODULE M
>   PRIVATE :: two
[...]
>   integer FUNCTION two() [...]
> END MODULE

> ! implementation, file (b)
> SUBROUTINE one(a)
>   USE M
>   integer :: a
>   a = two()
> END SUBROUTINE one

You are calling "two_" which is a REAL function and you are not calling an
INTEGER function and specifically you are not calling __m_MOD_two.
"two" is just an implicitly type external function.

> SUBROUTINE three(a)
>   integer :: a
>   a = two()
> END SUBROUTINE three

This one should be identical to "one".

> I often use modules simply to provide interfaces for subroutines implemented
> in other files and compiled into libraries

You should use ABSTRACT INTERFACE to provide interfaces...


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40973

[Bug fortran/40973] Mark PRIVATE module functions as STATIC to faciliate optimization

[dfranke at gcc dot gnu dot org]

------- Comment #1 from dfranke at gcc dot gnu dot org  2009-12-04 23:28 -------
How about this (somewhat constructed) example:

! interface module, file (a)
MODULE M
  PRIVATE :: two
CONTAINS
  SUBROUTINE one(a)
    integer :: a
  END SUBROUTINE one
  integer FUNCTION two()
  END FUNCTION two
END MODULE

! implementation, file (b)
SUBROUTINE one(a)
  USE M
  integer :: a
  a = two()
END SUBROUTINE one

integer FUNCTION two()
  two = 42
END FUNCTION two

! another user of the function, without using the interface module, file (c)
SUBROUTINE three(a)
  integer :: a
  a = two()
END SUBROUTINE three


I often use modules simply to provide interfaces for subroutines implemented in
other files and compiled into libraries, then distributing the interface
modules together with the library to avoid issues with .mod files of varying
compiler versions.


-- 

dfranke at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dfranke at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40973