[clang] [OpenACC] Implement `self` clause for compute constructs (PR #88760)

[Erich Keane via cfe-commits]

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@@ -72,3 +92,9 @@ void OpenACCClausePrinter::VisitDefaultClause(const OpenACCDefaultClause &C) {
 void OpenACCClausePrinter::VisitIfClause(const OpenACCIfClause &C) {
   OS << "if(" << C.getConditionExpr() << ")";
 }
+
+void OpenACCClausePrinter::VisitSelfClause(const OpenACCSelfClause &C) {
+  OS << "self";
+  if (const Expr *CondExpr = C.getConditionExpr())
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erichkeane wrote:

No, all that does is check if `CondExpr` is `nullptr`, so this is doing the same thing.  I thought this interface makes sense (that is, 'null' means no condition).

https://github.com/llvm/llvm-project/pull/88760