[flang-commits] [flang] [flang][OpenMP] Update all `lastprivate` symbols, not just in clauses (PR #125628)

[Leandro Lupori via flang-commits]

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@@ -207,6 +207,9 @@ void DataSharingProcessor::collectSymbolsForPrivatization() {
     }
   }
 
+  // TODO For common blocks, add the underlying objects within the block. Doing
+  // so, we won't need to explicitely handle block objects (or forget to do
+  // so).
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luporl wrote:

AFAIR, there are 2 things that complicate the handling of `sections`:

1. `omp.sections` can only have `omp.section` operations. So, privatizations must be performed before `omp.sections`.
2. `lastprivate` code must be inserted at the end of the last `omp.section`.

I guess this could be moved to DataSharingProcessor, but some special handling for `sections` would still be needed.

Also, we need to be careful when inserting barriers. As not all threads execute each section, inserting a barrier in a section can hang the program.

https://github.com/llvm/llvm-project/pull/125628