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

[Sergei Barannikov via llvm-commits]

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@@ -211,6 +220,11 @@ void XtensaTargetLowering::LowerAsmOperandForConstraint(
   TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
 }
 
+unsigned XtensaTargetLowering::getVaListSizeInBits(const DataLayout &DL) const {
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s-barannikov wrote:

Should be just a constexpr variable.

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