[llvm] [SelectionDAG] Add OPC_MoveSibling (PR #73643)

[Craig Topper via llvm-commits]

================
@@ -1066,6 +1077,9 @@ static StringRef getOpcodeString(Matcher::KindTy Kind) {
   case Matcher::RecordMemRef: return "OPC_RecordMemRef"; break;
   case Matcher::CaptureGlueInput: return "OPC_CaptureGlueInput"; break;
   case Matcher::MoveChild: return "OPC_MoveChild"; break;
+  case Matcher::MoveSibling:
+    return "OPC_MoveSibling";
+    break;
----------------
topperc wrote:

Can we delete all the unreachable `break`s in this switch as a separate patch?

https://github.com/llvm/llvm-project/pull/73643