[clang] [llvm] [Clang][OpenMP] Implement Loop splitting `#pragma omp split` directive (PR #183261)

[Michael Kruse via cfe-commits]

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@@ -2986,6 +2991,51 @@ OMPClause *Parser::ParseOpenMPSizesClause() {
                                                  OpenLoc, CloseLoc);
 }
 
+OMPClause *Parser::ParseOpenMPCountsClause() {
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Meinersbur wrote:

We need `split_messages.cpp` test file that checks the error conditions of this function using `-verify` and the `err_omp_split_counts_not_one_omp_fill` diagnostic.

https://github.com/llvm/llvm-project/pull/183261