This patch fixes "exit data" for (C++) reference-to-pointer struct
components with array sections, such as:
struct S { int *&ptr; [...] };
...
#pragma omp target exit data map(from: str->ptr, str->ptr[0:n])
Such exits need two "detach" operations. We need to unmap
both the pointer and the slice. That idiom is recognized by
omp_resolve_clause_dependencies, but before omp_build_struct_sibling_lists
finishes the resulting mapping nodes are represented like this:
GOMP_MAP_FROM GOMP_MAP_DETACH GOMP_MAP_ATTACH_DETACH
And at the moment, that won't be recognized as a single mapping group
as it should be. This patch fixes that.
(This is covered by a test case added in later patches in this series,
e.g. libgomp/testsuite/libgomp.c++/array-shaping-8.C.)
2023-07-03 Julian Brown <jul...@codesourcery.com>
gcc/
* gimplify.cc (omp_get_attachment): Handle GOMP_MAP_DETACH here.
(omp_group_last): Handle *, GOMP_MAP_DETACH, GOMP_MAP_ATTACH_DETACH
groups for "exit data" of reference-to-pointer component array
sections.
(omp_group_base): Handle GOMP_MAP_DETACH.
---
gcc/gimplify.cc | 30 ++++++++++++++++++++++++++----
1 file changed, 26 insertions(+), 4 deletions(-)
diff --git a/gcc/gimplify.cc b/gcc/gimplify.cc
index 20aba45110f..6280eb7e028 100644
--- a/gcc/gimplify.cc
+++ b/gcc/gimplify.cc
@@ -9171,6 +9171,7 @@ omp_get_attachment (omp_mapping_group *grp)
case GOMP_MAP_ATTACH_DETACH:
case GOMP_MAP_ATTACH_ZERO_LENGTH_ARRAY_SECTION:
+ case GOMP_MAP_DETACH:
return OMP_CLAUSE_DECL (node);
default:
@@ -9247,23 +9248,43 @@ omp_group_last (tree *start_p)
== GOMP_MAP_POINTER_TO_ZERO_LENGTH_ARRAY_SECTION)
|| (OMP_CLAUSE_MAP_KIND (nc)
== GOMP_MAP_ATTACH_ZERO_LENGTH_ARRAY_SECTION)
+ || OMP_CLAUSE_MAP_KIND (nc) == GOMP_MAP_DETACH
|| OMP_CLAUSE_MAP_KIND (nc) == GOMP_MAP_ALWAYS_POINTER
|| omp_map_clause_descriptor_p (nc)))
{
- grp_last_p = &OMP_CLAUSE_CHAIN (c);
- c = nc;
tree nc2 = OMP_CLAUSE_CHAIN (nc);
+ if (OMP_CLAUSE_MAP_KIND (nc) == GOMP_MAP_DETACH)
+ {
+ /* In the specific case we're doing "exit data" on an array
+ slice of a reference-to-pointer struct component, we will see
+ DETACH followed by ATTACH_DETACH here. We want to treat that
+ as a single group. In other cases DETACH might represent a
+ stand-alone "detach" clause, so we don't want to consider
+ that part of the group. */
+ if (nc2
+ && OMP_CLAUSE_CODE (nc2) == OMP_CLAUSE_MAP
+ && OMP_CLAUSE_MAP_KIND (nc2) == GOMP_MAP_ATTACH_DETACH)
+ goto consume_two_nodes;
+ else
+ break;
+ }
if (nc2
&& OMP_CLAUSE_CODE (nc2) == OMP_CLAUSE_MAP
&& (OMP_CLAUSE_MAP_KIND (nc)
== GOMP_MAP_POINTER_TO_ZERO_LENGTH_ARRAY_SECTION)
&& OMP_CLAUSE_MAP_KIND (nc2) == GOMP_MAP_ATTACH)
{
+ consume_two_nodes:
grp_last_p = &OMP_CLAUSE_CHAIN (nc);
c = nc2;
- nc2 = OMP_CLAUSE_CHAIN (nc2);
+ nc = OMP_CLAUSE_CHAIN (nc2);
+ }
+ else
+ {
+ grp_last_p = &OMP_CLAUSE_CHAIN (c);
+ c = nc;
+ nc = nc2;
}
- nc = nc2;
}
break;
@@ -9416,6 +9437,7 @@ omp_group_base (omp_mapping_group *grp, unsigned int
*chained,
case GOMP_MAP_ALWAYS_POINTER:
case GOMP_MAP_ATTACH_DETACH:
case GOMP_MAP_ATTACH_ZERO_LENGTH_ARRAY_SECTION:
+ case GOMP_MAP_DETACH:
return *grp->grp_start;
default:
--
2.25.1
