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

[Matt Arsenault via llvm-commits]

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@@ -837,6 +837,8 @@ void MIPrinter::print(const MachineInstr &MI) {
     OS << "disjoint ";
   if (MI.getFlag(MachineInstr::NoUSWrap))
     OS << "nusw ";
+  if (MI.getFlag(MachineInstr::SameSign))
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arsenm wrote:

Should get mir print / parse test

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