[clang] [OpenACC][NFC] Implement basic OpenACC Sema infrastructure (PR #81874)

[Erich Keane via cfe-commits]

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@@ -1197,7 +1215,20 @@ StmtResult Parser::ParseOpenACCDirectiveStmt() {
   ParsingOpenACCDirectiveRAII DirScope(*this);
   ConsumeAnnotationToken();
 
-  ParseOpenACCDirective();
+  OpenACCDirectiveParseInfo DirInfo = ParseOpenACCDirective();
+  if (getActions().ActOnStartOpenACCDeclDirective(DirInfo.DirKind,
+                                                  DirInfo.StartLoc))
+    return StmtError();
+
+  StmtResult AssocStmt;
+
+  if (doesDirectiveHaveAssociatedStmt(DirInfo.DirKind)) {
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erichkeane wrote:

This section ends up being slightly worse without being able to check the AST kind here, so we need a separate function to check whether we need to parse one.  However, this removes the ASTContext function that was troublesome.

https://github.com/llvm/llvm-project/pull/81874