[clang] [CIR] Upstream emitAndUpdateRetAlloca (PR #129933)

[Andy Kaylor via cfe-commits]

================
@@ -312,4 +326,12 @@ LValue CIRGenFunction::emitLValue(const Expr *e) {
   }
 }
 
+void CIRGenFunction::emitAndUpdateRetAlloca(QualType ty, mlir::Location loc,
+                                            CharUnits alignment) {
+  if (ty->isVoidType()) {
+    return;
+  }
+
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andykaylor wrote:

You should bring in the extra checks from the incubator for cases that are marked `llvm_unreachable("NYI");` but use cgm.errorNYI() instead.

https://github.com/llvm/llvm-project/pull/129933