Dear all,
the attached patch only sets TREE_PUBLIC for module variables and module
procedures which have neither the PRIVATE attribute nor a C-binding
label. Seemingly, only NAG f95 does this for module variables and none
of my compilers does this for module procedures.
The main effect of this patch is a code size reduction as the compiler
might (even without -fwhole-program -flto) optimize unused
variables/procedures away. Additionally, the compiler might inline code
which it otherwise wouldn't do (due to the code size increase) or do
optimizations based on the value of the module variables (though, GCC
has room for improvement for optimizing static variables.)
Note: For C-binding variables without binding label ("bind(C,
name='')"), I don't use DECL_COMMON. That should be okay as DECL_COMMON
is only used to make sure that a variable can be initialized from either
C or Fortran. But without binding name, that's not possible from C,
hence, that's fine.
Build and regtested on x86-64-linux. (And currently regtesting again -
after a minor modification.)
OK for the trunk?
Tobias
2012-04-03 Tobias Burnus <bur...@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.
2012-04-03 Tobias Burnus <bur...@net-b.de>
PR fortran/40973
PR fortran/52751
* gfortran.dg/public_private_module_2.f90: New.
diff --git a/gcc/fortran/trans-decl.c b/gcc/fortran/trans-decl.c
index 8a1dd2e..23cf052 100644
--- a/gcc/fortran/trans-decl.c
+++ b/gcc/fortran/trans-decl.c
@@ -539,7 +539,7 @@ gfc_finish_var_decl (tree decl, gfc_symbol * sym)
if (sym->attr.cray_pointee)
return;
- if(sym->attr.is_bind_c == 1)
+ if(sym->attr.is_bind_c == 1 && sym->binding_label)
{
/* We need to put variables that are bind(c) into the common
segment of the object file, because this is what C would do.
@@ -565,7 +565,8 @@ gfc_finish_var_decl (tree decl, gfc_symbol * sym)
/* TODO: Don't set sym->module for result or dummy variables. */
gcc_assert (current_function_decl == NULL_TREE || sym->result == sym);
/* This is the declaration of a module variable. */
- TREE_PUBLIC (decl) = 1;
+ if (sym->attr.access != ACCESS_PRIVATE)
+ TREE_PUBLIC (decl) = 1;
TREE_STATIC (decl) = 1;
}
@@ -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);
--- /dev/null 2012-03-22 21:06:43.387787737 +0100
+++ gcc/gcc/testsuite/gfortran.dg/public_private_module_2.f90 2012-04-03 23:02:59.000000000 +0200
@@ -0,0 +1,70 @@
+! { dg-do compile }
+! { dg-options "-O2" }
+!
+! PR fortran/52751 (top, "module mod")
+! PR fortran/40973 (bottom, "module m"
+!
+! Ensure that (only) those module variables and procedures which are PRIVATE
+! and have no C-binding label are optimized away.
+!
+ module mod
+ integer :: aa
+ integer, private :: iii
+ integer, private, bind(C) :: jj ! { dg-warning "PRIVATE but has been given the binding label" }
+ integer, private, bind(C,name='lll') :: kk ! { dg-warning "PRIVATE but has been given the binding label" }
+ integer, private, bind(C,name='') :: mmmm
+ integer, bind(C) :: nnn
+ integer, bind(C,name='oo') :: pp
+ integer, bind(C,name='') :: qq
+ end module mod
+
+ ! { dg-final { scan-assembler "__mod_MOD_aa" } }
+ ! { dg-final { scan-assembler-not "iii" } }
+ ! { dg-final { scan-assembler "jj" } }
+ ! { dg-final { scan-assembler "lll" } }
+ ! { dg-final { scan-assembler-not "kk" } }
+ ! { dg-final { scan-assembler-not "mmmm" } }
+ ! { dg-final { scan-assembler "nnn" } }
+ ! { dg-final { scan-assembler "oo" } }
+ ! { dg-final { scan-assembler "__mod_MOD_qq" } }
+
+MODULE M
+ PRIVATE :: two, three, four, six
+ PUBLIC :: one, seven, eight, ten
+CONTAINS
+ SUBROUTINE one(a)
+ integer :: a
+ a = two()
+ END SUBROUTINE one
+ integer FUNCTION two()
+ two = 42
+ END FUNCTION two
+ integer FUNCTION three() bind(C) ! { dg-warning "PRIVATE but has been given the binding label" }
+ three = 43
+ END FUNCTION three
+ integer FUNCTION four() bind(C, name='five') ! { dg-warning "PRIVATE but has been given the binding label" }
+ four = 44
+ END FUNCTION four
+ integer FUNCTION six() bind(C, name='')
+ six = 46
+ END FUNCTION six
+ integer FUNCTION seven() bind(C)
+ seven = 46
+ END FUNCTION seven
+ integer FUNCTION eight() bind(C, name='nine')
+ eight = 48
+ END FUNCTION eight
+ integer FUNCTION ten() bind(C, name='')
+ ten = 48
+ END FUNCTION ten
+END MODULE
+
+! { dg-final { scan-assembler "__m_MOD_one" } }
+! { dg-final { scan-assembler-not "two" } }
+! { dg-final { scan-assembler "three" } }
+! { dg-final { scan-assembler-not "four" } }
+! { dg-final { scan-assembler "five" } }
+! { dg-final { scan-assembler-not "six" } }
+! { dg-final { scan-assembler "seven" } }
+! { dg-final { scan-assembler "nine" } }
+! { dg-final { scan-assembler "__m_MOD_ten" } }
