[llvm] [SelectionDAG] Add preliminary plumbing for `samesign` flag (PR #112354)

[Antonio Frighetto via llvm-commits]

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@@ -1267,7 +1267,7 @@ class MachineIRBuilder {
   /// \return a MachineInstrBuilder for the newly created instruction.
   MachineInstrBuilder buildICmp(CmpInst::Predicate Pred, const DstOp &Res,
                                 const SrcOp &Op0, const SrcOp &Op1,
-                                std::optional<unsigned> Flgs = std::nullopt);
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antoniofrighetto wrote:

I took the minor opportunity to fix the typo within this patch, will undo if you have a strong concern on this.

https://github.com/llvm/llvm-project/pull/112354