[flang-commits] [flang] [flang][debug] Don't generate debug for compiler-generated variables (PR #112423)

[via flang-commits]

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@@ -211,10 +211,13 @@ void AddDebugInfoPass::handleGlobalOp(fir::GlobalOp globalOp,
   if (result.first != fir::NameUniquer::NameKind::VARIABLE)
     return;
 
-  // Discard entries that describe a derived type. Usually start with '.c.',
-  // '.dt.' or '.n.'. It would be better if result of the deconstruct had a flag
-  // for such values so that we dont have to look at string values.
-  if (!result.second.name.empty() && result.second.name[0] == '.')
+  // Discard entries that describe a derived type. They start with either '.' or
+  // 'X'. We filter both of them out. Note that NameUniquer makes the name lower
+  // case so user variables should be safe. It would be better if result of the
+  // deconstruct had a flag for such values so that we dont have to look at
+  // string values.
+  if (!result.second.name.empty() &&
+      (result.second.name[0] == '.' || result.second.name[0] == 'X'))
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jeanPerier wrote:

Please move the `result.second.name[0] == '.' || result.second.name[0] == 'X'` part into some `static fir::NameUniquer::isSpecialSymbol(llvm::StringRef name)` helper in `Optimizer/Support/InternalNames` so that the usages of these delimiters are better centralized and advertise.

Long term, it may be better to have some compiler generated flag attributes on the global/declare for such variables (and others) rather than relying on the names.
In semantics, these variables are tagged with the `CompilerCreated` symbol attribute, but it is currently not represented in FIR.

https://github.com/llvm/llvm-project/pull/112423