[Openmp-commits] [PATCH] D105121: [OpenMP] Avoid checking parent reference count in targetDataBegin

[Joachim Protze via Phabricator via Openmp-commits]

protze.joachim added a comment.

I think, we need more tests challenging the reference counting for mapping rules to make sure that the code change is valid.

Also, is the expectation that the implementation respects the 5.2 clarifications/changes regarding reference counting of struct members (probably issue #1909)?



================
Comment at: openmp/libomptarget/src/omptarget.cpp:541-542
           copy = true;
-        } else if ((arg_types[i] & OMP_TGT_MAPTYPE_MEMBER_OF) &&
-                   !(arg_types[i] & OMP_TGT_MAPTYPE_PTR_AND_OBJ)) {
-          // Copy data only if the "parent" struct has RefCount==1.
----------------
What is the meaning of these flags?

In code like the following, the `target` region should not copy any data, because S is already mapped in the `enter data`
```
struct{int a; int b;}s_s S;
#pragma omp target enter data map(to:S)
#pragma omp target map(tofrom:S.b)
{...}
#pragma omp target exit data map(from:S)
```


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  https://reviews.llvm.org/D105121/new/

https://reviews.llvm.org/D105121