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

[Eli Friedman via cfe-commits]

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@@ -789,27 +791,37 @@ Address AArch64ABIInfo::EmitAAPCSVAArg(Address VAListAddr, QualType Ty,
                                  OnStackBlock, "vaargs.addr");
 
   if (IsIndirect)
-    return Address(CGF.Builder.CreateLoad(ResAddr, "vaarg.addr"), ElementTy,
-                   TyAlign);
-
-  return ResAddr;
+    return CGF.EmitLoadOfAnyValue(
+        CGF.MakeAddrLValue(
+            Address(CGF.Builder.CreateLoad(ResAddr, "vaarg.addr"), ElementTy,
+                    TyAlign),
+            Ty),
+        Slot);
+
+  return CGF.EmitLoadOfAnyValue(CGF.MakeAddrLValue(ResAddr, Ty), Slot);
 }
 
-Address AArch64ABIInfo::EmitDarwinVAArg(Address VAListAddr, QualType Ty,
-                                        CodeGenFunction &CGF) const {
+RValue AArch64ABIInfo::EmitDarwinVAArg(Address VAListAddr, QualType Ty,
+                                       CodeGenFunction &CGF,
+                                       AggValueSlot Slot) const {
   // The backend's lowering doesn't support va_arg for aggregates or
   // illegal vector types.  Lower VAArg here for these cases and use
   // the LLVM va_arg instruction for everything else.
   if (!isAggregateTypeForABI(Ty) && !isIllegalVectorType(Ty))
-    return EmitVAArgInstr(CGF, VAListAddr, Ty, ABIArgInfo::getDirect());
+    return CGF.EmitLoadOfAnyValue(
+        CGF.MakeAddrLValue(
+            EmitVAArgInstr(CGF, VAListAddr, Ty, ABIArgInfo::getDirect()), Ty),
+        Slot);
 
   uint64_t PointerSize = getTarget().getPointerWidth(LangAS::Default) / 8;
   CharUnits SlotSize = CharUnits::fromQuantity(PointerSize);
 
   // Empty records are ignored for parameter passing purposes.
-  if (isEmptyRecord(getContext(), Ty, true))
-    return Address(CGF.Builder.CreateLoad(VAListAddr, "ap.cur"),
-                   CGF.ConvertTypeForMem(Ty), SlotSize);
+  if (isEmptyRecord(getContext(), Ty, true)) {
+    Address ResAddr = Address(CGF.Builder.CreateLoad(VAListAddr, "ap.cur"),
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efriedma-quic wrote:

That said, it might not really matter in this context... CGExprAgg ignores the return value.  But still, there's no point to constructing a load that will never be used.

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