[llvm] [CodeGen] Stop exporting cl::opts. NFC (PR #228728)

[Reid Kleckner via llvm-commits]

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@@ -867,6 +867,23 @@ void SwingSchedulerDAG::setMAX_II() {
     MAX_II = MII + SwpIISearchRange;
 }
 
+SwingSchedulerDAG::SwingSchedulerDAG(MachineFunction &MF,
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rnk wrote:

Out-of-line complex ctors is better anyway, since it's an anchor method for complete field types, debug info, etc etc.

https://github.com/llvm/llvm-project/pull/228728