[clang] [clang][CodeGen] Return RValue from `EmitVAArg` (PR #94635)

[Eli Friedman via cfe-commits]

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@@ -4777,6 +4783,13 @@ class CodeGenFunction : public CodeGenTypeCache {
   /// aggregate type into a temporary LValue.
   LValue EmitAggExprToLValue(const Expr *E);
 
+  enum ExprValueKind { EVK_RValue, EVK_NonRValue };
+
+  /// EmitAggFinalDestCopy - Emit copy of the specified aggregate into
+  /// destination address.
+  void EmitAggFinalDestCopy(QualType Type, AggValueSlot Dest, const LValue &Src,
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efriedma-quic wrote:

It feels strange to be adding this API now... but I guess it's fine?  The alternative would be to use EmitAggregateCopy directly.  It only really makes a difference for structs containing pointers to ObjC types, which can't be passed by va_arg anyway, but I guess it's better for EmitLoadOfAnyValue to be fully general in case we add other uses in the future.

https://github.com/llvm/llvm-project/pull/94635