[clang] [clang-format] Support of TableGen formatting. (PR #76059)

[Emilia Kond via cfe-commits]

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@@ -272,6 +276,38 @@ void FormatTokenLexer::tryMergePreviousTokens() {
       return;
     }
   }
+  if (Style.isTableGen()) {
+    if (tryMergeTokens({tok::l_square, tok::l_brace},
+                       TT_TableGenMultiLineString)) {
+      Tokens.back()->Tok.setKind(tok::string_literal);
+      return;
+    }
+    if (Tokens.size() > 1 && Tokens.end()[-2]->is(tok::exclaim)) {
+      if (Tokens.back()->is(tok::identifier) ||
+          (Tokens.back()->is(tok::kw_if) && Tokens.back())) {
+      }
+    }
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rymiel wrote:

This if statement does nothing, or am I misunderstanding it?

https://github.com/llvm/llvm-project/pull/76059