[clang] [CIR] Upstream support for emitting constructors (PR #143639)

[Erich Keane via cfe-commits]

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@@ -55,12 +59,29 @@ class CIRGenCXXABI {
     return md->getParent();
   }
 
+  /// Return whether the given global decl needs a VTT parameter.
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erichkeane wrote:

can we say what a VTT parameter is?

https://github.com/llvm/llvm-project/pull/143639