[llvm] [Frontend] Introduce `getDirectiveCategory` for ACC/OMP directives (PR #94689)

[Krzysztof Parzyszek via llvm-commits]

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@@ -1033,39 +1087,46 @@ def OMP_Teams : Directive<"teams"> {
     VersionedClause<OMPC_ThreadLimit>,
   ];
   let association = AS_Block;
+  let category = CA_Executable;
 }
 def OMP_ThreadPrivate : Directive<"threadprivate"> {
   let association = AS_None;
+  let category = CA_Declarative;
 }
 def OMP_Tile : Directive<"tile"> {
   let allowedOnceClauses = [
     VersionedClause<OMPC_Sizes, 51>,
   ];
   let association = AS_Loop;
+  let category = CA_Executable;
 }
 def OMP_Unknown : Directive<"unknown"> {
   let isDefault = true;
   let association = AS_None;
+  let category = CA_Utility;
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kparzysz wrote:

The `OMPC_unknown` constant has been present for a while in the LLVM sources.  Clang uses it in a few places as a value that means "none".  I haven't seen any documentation for it other than actual usage.

https://github.com/llvm/llvm-project/pull/94689