[Bug middle-end/99928] [OpenMP] reduction variable in combined target construct wrongly mapped as firstprivate

["cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99928

--- Comment #14 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:c94424b0ed786ec92b6904da69af8b5243b34fdc

commit r12-1109-gc94424b0ed786ec92b6904da69af8b5243b34fdc
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Fri May 28 11:26:48 2021 +0200

    openmp: Fix up handling of reduction clause on constructs combined with
target [PR99928]

    The reduction clause should be copied as map (tofrom: ) to combined target
if
    present, but as we need different handling of array sections between map
and reduction,
    doing that during gimplification would be harder.

    So, this patch adds them during splitting, and similarly to firstprivate
adds them
    with a new flag that they should be just ignored/removed if an explicit map
clause
    of the same list item is present.

    The exact rules are to be decided in
https://github.com/OpenMP/spec/issues/2766
    so this patch just implements something that is IMHO reasonable and exact
detailed
    testcases for the cornercases will follow once it is clarified.

    2021-05-28  Jakub Jelinek  <jakub@redhat.com>

            PR middle-end/99928
    gcc/
            * tree.h (OMP_CLAUSE_MAP_IMPLICIT): Define.
    gcc/c-family/
            * c-omp.c (c_omp_split_clauses): For reduction clause if combined
with
            target add a map tofrom clause with OMP_CLAUSE_MAP_IMPLICIT.
    gcc/c/
            * c-typeck.c (handle_omp_array_sections): Copy
OMP_CLAUSE_MAP_IMPLICIT.
            (c_finish_omp_clauses): Move not just
OMP_CLAUSE_FIRSTPRIVATE_IMPLICIT
            marked clauses last, but also OMP_CLAUSE_MAP_IMPLICIT.  Add
            map_firstprivate_head bitmap, set it for
GOMP_MAP_FIRSTPRIVATE_POINTER
            maps and silently remove OMP_CLAUSE_FIRSTPRIVATE_IMPLICIT if it is
            present too.  For OMP_CLAUSE_MAP_IMPLICIT silently remove the
clause
            if present in map_head, map_field_head or map_firstprivate_head
            bitmaps.
    gcc/cp/
            * semantics.c (handle_omp_array_sections): Copy
            OMP_CLAUSE_MAP_IMPLICIT.
            (finish_omp_clauses): Move not just
OMP_CLAUSE_FIRSTPRIVATE_IMPLICIT
            marked clauses last, but also OMP_CLAUSE_MAP_IMPLICIT.  Add
            map_firstprivate_head bitmap, set it for
GOMP_MAP_FIRSTPRIVATE_POINTER
            maps and silently remove OMP_CLAUSE_FIRSTPRIVATE_IMPLICIT if it is
            present too.  For OMP_CLAUSE_MAP_IMPLICIT silently remove the
clause
            if present in map_head, map_field_head or map_firstprivate_head
            bitmaps.
    gcc/testsuite/
            * c-c++-common/gomp/pr99928-8.c: Remove all xfails.
            * c-c++-common/gomp/pr99928-9.c: Likewise.
            * c-c++-common/gomp/pr99928-10.c: Likewise.
            * c-c++-common/gomp/pr99928-16.c: New test.