[Bug fortran/62278] New: gfc_check_dependency should also check for TARGET attribute

[Bug fortran/62278] New: gfc_check_dependency should also check for TARGET attribute

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62278

            Bug ID: 62278
           Summary: gfc_check_dependency should also check for TARGET
                    attribute
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: burnus at gcc dot gnu.org
                CC: tkoenig at gcc dot gnu.org

When playing around with https://gcc.gnu.org/ml/fortran/2014-08/msg00109.html,
using 

  gfc_check_dependency (lhs_expr, rhs_expr, false) 

I saw that for the following, the "P(:)" and "A(:)" expressions are regarded as
potentially depending on each other. However, I fail how that should be
possible as "A" neither has the TARGET nor the POINTER attribute.


integer, save :: A(10)[*]
integer, pointer :: P(:)

P(:) = A(:)[i]
end

[Bug fortran/62278] gfc_check_dependency should also check for TARGET attribute

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62278

--- Comment #1 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Note: The code deciding whether a temporary is required seems to do additional
checks, at least for the simple noncoarray assignment, no temporary is
generated.

[Bug fortran/62278] gfc_check_dependency should also check for TARGET attribute

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62278

--- Comment #2 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
Can you provide an example?

The simplistic case of

subroutine foo(p)
  integer, save :: a(10)[*]
  integer, pointer :: p(:)
  p(:) = a(:)
end subroutine foo
ig25@linux-fd1f:~/Krempel/Point> gfortran -c -O -fcoarray=single
-Warray-temporaries foo.f90

doesn't triger anything.

[Bug fortran/62278] gfc_check_dependency should also check for TARGET attribute

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62278

--- Comment #3 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Author: burnus
Date: Sat Aug 30 18:47:04 2014
New Revision: 214757

URL: https://gcc.gnu.org/viewcvs?rev=214757&root=gcc&view=rev
Log:
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.


Modified:
    trunk/gcc/fortran/ChangeLog
    trunk/gcc/fortran/dependency.c

[Bug fortran/62278] gfc_check_dependency should also check for TARGET attribute

[dominiq at lps dot ens.fr]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62278

Dominique d'Humieres <dominiq at lps dot ens.fr> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-09-02
     Ever confirmed|0                           |1

--- Comment #4 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
Some tests are needed.