[llvm] DAG: Handle poison in m_Undef (PR #168288)

[Min-Yih Hsu via llvm-commits]

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@@ -222,7 +222,9 @@ template <typename... Preds> auto m_NoneOf(const Preds &...preds) {
 
 inline Opcode_match m_Opc(unsigned Opcode) { return Opcode_match(Opcode); }
 
-inline Opcode_match m_Undef() { return Opcode_match(ISD::UNDEF); }
+template <typename... Preds> auto m_Undef() {
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mshockwave wrote:

unused `template <typename... Preds>`

https://github.com/llvm/llvm-project/pull/168288