[llvm] Eliminating li of 0 into arg registers of unused arguments (PR #122741)

[Hubert Tong via llvm-commits]

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@@ -9237,6 +9263,11 @@ SDValue SelectionDAG::getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
 
   SDVTList VTs = Indexed ?
     getVTList(VT, Ptr.getValueType(), MVT::Other) : getVTList(VT, MVT::Other);
+
+  // FixedMe: lower poison to undef.
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hubert-reinterpretcast wrote:

Same comment. Also: I think the convention is `FIXME`.

https://github.com/llvm/llvm-project/pull/122741