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

[Erich Keane via cfe-commits]

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@@ -72,6 +82,72 @@ void CIRGenItaniumCXXABI::emitInstanceFunctionProlog(SourceLocation loc,
   }
 }
 
+void CIRGenItaniumCXXABI::addImplicitStructorParams(CIRGenFunction &cgf,
+                                                    QualType &retTY,
+                                                    FunctionArgList &params) {
+  const auto *md = cast<CXXMethodDecl>(cgf.curGD.getDecl());
+  assert(isa<CXXConstructorDecl>(md) || isa<CXXDestructorDecl>(md));
+
+  // Check if we need a VTT parameter as well.
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erichkeane wrote:

as well as what?  Seems this function is a noop besides an assert... We probably should find some use of `md` here else this is going to warn.

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