[llvm] [Xtensa] Implement vararg support. (PR #117126)

[Andrei Safronov via llvm-commits]

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@@ -394,20 +382,18 @@ SDValue XtensaTargetLowering::LowerFormalArguments(
   }
 
   if (IsVarArg) {
-    static const MCPhysReg XtensaArgRegs[6] = {
-        Xtensa::A2, Xtensa::A3, Xtensa::A4, Xtensa::A5, Xtensa::A6, Xtensa::A7};
-    ArrayRef<MCPhysReg> ArgRegs = ArrayRef(XtensaArgRegs);
+    ArrayRef<MCPhysReg> ArgRegs = ArrayRef(IntRegs);
     unsigned Idx = CCInfo.getFirstUnallocated(ArgRegs);
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andreisfr wrote:

Fixed

https://github.com/llvm/llvm-project/pull/117126