[clang] [llvm] [openmp] [Clang][OpenMP] Add `#pragma omp flatten` loop directive + `depth` clause (PR #206977)

[Michael Kruse via cfe-commits]

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@@ -381,7 +381,7 @@ implementation.
 | Feature                                                               | C/C++ Status        | Fortran Status      | Reviews                                                                                                  |
 | --------------------------------------------------------------------- | ------------------- | ------------------- | -------------------------------------------------------------------------------------------------------- |
 | dyn_groupprivate clause                                               | {part}`partial`     | {part}`In Progress` | C/C++: Host device support missing                                                                       |
-| loop flatten transformation                                           | {none}`unclaimed`   | {none}`unclaimed`   |                                                                                                          |
+| loop flatten transformation                                           | {good}`done`        | {none}`unclaimed`   | Clang: @loopacino ([PR206977][PR206977])                                                                 |
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Meinersbur wrote:

Support is only partial: support for non-rectangular loops is missing

https://github.com/llvm/llvm-project/pull/206977