From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
 id B72E63858430; Mon, 14 Mar 2022 14:48:17 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org B72E63858430
From: "burnus at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/104696] [OpenMP] component/array-ref/component
 (x.r[1].d) should use 'x' for GOMP_MAP_STRUCT (not yield 'x.r[1]' for nonptr
 'x.r')
Date: Mon, 14 Mar 2022 14:48:17 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: middle-end
X-Bugzilla-Version: 12.0
X-Bugzilla-Keywords: missed-optimization, openmp, wrong-code
X-Bugzilla-Severity: normal
X-Bugzilla-Who: burnus at gcc dot gnu.org
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 12.0
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: component short_desc
Message-ID: <bug-104696-4-cFYR3Aupf1@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-104696-4@http.gcc.gnu.org/bugzilla/>
References: <bug-104696-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-BeenThere: gcc-bugs@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Gcc-bugs mailing list <gcc-bugs.gcc.gnu.org>
List-Unsubscribe: <https://gcc.gnu.org/mailman/options/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-request@gcc.gnu.org?subject=help>
List-Subscribe: <https://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Mon, 14 Mar 2022 14:48:17 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104696

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|fortran                     |middle-end
            Summary|[OpenMP] Implicit mapping   |[OpenMP]
                   |breaks struct mapping       |component/array-ref/compone
                   |                            |nt (x.r[1].d) should use
                   |                            |'x' for GOMP_MAP_STRUCT
                   |                            |(not yield 'x.r[1]' for
                   |                            |nonptr 'x.r')

--- Comment #5 from Tobias Burnus <burnus at gcc dot gnu.org> ---
(In reply to Tobias Burnus from comment #4)
>   #pragma omp target map(tofrom: x.r[1].d)
>    *.r[1].d =3D 3;

s/*/x/

The problem is that in gimplify.cc's gimplify_scan_omp_clauses:

                  tree base
                    =3D extract_base_bit_offset (OMP_CLAUSE_DECL (c), &base=
_ref,
                                               &bitpos1, &offset1,
                                               &tree_offset1);
                  bool do_map_struct =3D (base =3D=3D decl && !tree_offset1=
);

Here, 'base' =3D=3D 'x' but 'decl' is 'x.r[1]' - while for 'x.q.d' it is 'x=
' (=3D=3D
base).

The comp refs are removed as follows. (It seems as if some additional ARRAY=
_REF
checking is needed for non-pointer components.)

              else if (TREE_CODE (decl) =3D=3D COMPONENT_REF
                       && (OMP_CLAUSE_MAP_KIND (c)
                           !=3D GOMP_MAP_ATTACH_ZERO_LENGTH_ARRAY_SECTION))
                {=20
                  component_ref_p =3D true;=20
                  while (TREE_CODE (decl) =3D=3D COMPONENT_REF)
                    decl =3D TREE_OPERAND (decl, 0);
                  if (TREE_CODE (decl) =3D=3D INDIRECT_REF
                      && DECL_P (TREE_OPERAND (decl, 0))
                      && (TREE_CODE (TREE_TYPE (TREE_OPERAND (decl, 0)))
                          =3D=3D REFERENCE_TYPE))
                    decl =3D TREE_OPERAND (decl, 0);
                }

Probably the same for '!DECL_P (decl)' in the previous 'if' branch.=