re PR fortran/62278 (gfc_check_dependency should also check for TARGET attribute)

2014-08-30  Tobias Burnus  <burnus@net-b.de>

        PR fortran/62278
        PR fortran/44735
        PR fortran/60593
        * dependency.c (gfc_check_dependency): Allow for optimizations
        in the pointer-alias check.

From-SVN: r214757

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 7c4a2c4a0aecfca284b1bcd7174f8e6c343adae3..b9706f4450d75a8284a1b29c612a6240a7acf489 100644 (file)
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,11 @@
+2014-08-30  Tobias Burnus  <burnus@net-b.de>
+
+       PR fortran/62278
+       PR fortran/44735
+       PR fortran/60593
+       * dependency.c (gfc_check_dependency): Allow for optimizations
+       in the pointer-alias check.
+
 2014-08-30  Janne Blomqvist  <jb@gcc.gnu.org>
 
        * module.c (gfc_dump_module): Use ISO C remove() instead of POSIX

diff --git a/gcc/fortran/dependency.c b/gcc/fortran/dependency.c
index c18482aff2e3719ccb84adfb9a58e90016793baa..367b323eae2c128223acc12225347629a011ce84 100644 (file)
--- a/gcc/fortran/dependency.c
+++ b/gcc/fortran/dependency.c
@@ -1269,6 +1269,7 @@ gfc_check_dependency (gfc_expr *expr1, gfc_expr *expr2, bool identical)
       /* The interesting cases are when the symbols don't match.  */
       if (expr1->symtree->n.sym != expr2->symtree->n.sym)
        {
+         symbol_attribute attr1, attr2;
          gfc_typespec *ts1 = &expr1->symtree->n.sym->ts;
          gfc_typespec *ts2 = &expr2->symtree->n.sym->ts;
 
@@ -1284,9 +1285,13 @@ gfc_check_dependency (gfc_expr *expr1, gfc_expr *expr2, bool identical)
                return 0;
            }
 
-         /* If either variable is a pointer, assume the worst.  */
-         /* TODO: -fassume-no-pointer-aliasing */
-         if (gfc_is_data_pointer (expr1) || gfc_is_data_pointer (expr2))
+         /* We have to also include target-target as ptr%comp is not a
+            pointer but it still alias with "dt%comp" for "ptr => dt".  As
+            subcomponents and array access to pointers retains the target
+            attribute, that's sufficient.  */
+         attr1 = gfc_expr_attr (expr1);
+         attr2 = gfc_expr_attr (expr2);
+         if ((attr1.pointer || attr1.target) && (attr2.pointer || attr2.target))
            {
              if (check_data_pointer_types (expr1, expr2)
                    && check_data_pointer_types (expr2, expr1))