[clang] [SystemZ][z/OS] Implement #pragma export (PR #141671)

[Erich Keane via cfe-commits]

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@@ -1395,6 +1411,171 @@ bool Parser::HandlePragmaMSAllocText(StringRef PragmaName,
   return true;
 }
 
+NestedNameSpecifier *
+Parser::zOSParseIdentifier(StringRef PragmaName,
+                           const IdentifierInfo *IdentName) {
+  NestedNameSpecifier *NestedId = nullptr;
+  if (PP.getLangOpts().CPlusPlus) {
+    if (Tok.is(tok::coloncolon)) {
+      // Nothing to do.
+    } else if (Actions.CurContext->isNamespace()) {
+      auto *NS = cast<NamespaceDecl>(Actions.CurContext);
+      NestedId =
+          NestedNameSpecifier::Create(Actions.Context, NS->getIdentifier());
+      NestedId =
+          NestedNameSpecifier::Create(Actions.Context, NestedId, IdentName);
+      PP.Lex(Tok);
+    } else {
+      NestedId = NestedNameSpecifier::Create(Actions.Context, IdentName);
+      PP.Lex(Tok);
+    }
+    while (Tok.is(tok::coloncolon)) {
+      PP.Lex(Tok);
+      if (Tok.isNot(tok::identifier)) {
+        PP.Diag(Tok.getLocation(), diag::warn_pragma_expected_identifier)
+            << PragmaName;
+        return nullptr;
+      }
+      IdentifierInfo *II = Tok.getIdentifierInfo();
+      NestedId = NestedNameSpecifier::Create(Actions.Context, NestedId, II);
+      PP.Lex(Tok);
+    }
+  } else {
+    NestedId = NestedNameSpecifier::Create(Actions.Context, IdentName);
+    PP.Lex(Tok);
+  }
+  return NestedId;
+}
+
+bool Parser::zOSParseParameterList(
+    StringRef PragmaName, std::optional<SmallVector<QualType, 4>> &TypeList,
+    Qualifiers &CVQual) {
+  if (Tok.is(tok::l_paren)) {
+    TypeList = SmallVector<QualType, 4>();
+    PP.Lex(Tok);
+    while (Tok.isNot(tok::eof) && !Tok.is(tok::r_paren)) {
+      TypeResult TResult = ParseTypeName(nullptr);
+      if (!TResult.isInvalid()) {
+        QualType QT = TResult.get().get();
+        if (!QT.getTypePtr()->isVoidType()) {
+          TypeList->push_back(QT);
----------------
erichkeane wrote:

This feels lossy... Also, why are we allowing 'void' in this list at all?

https://github.com/llvm/llvm-project/pull/141671