[llvm] [CycleInfo] Represent cycles by an opaque handle. NFC (PR #210117)

[Fangrui Song via llvm-commits]

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@@ -47,7 +46,7 @@ class LLVM_ABI MachineCycleInfoWrapperPass : public MachineFunctionPass {
 // TODO: add this function to the GenericCycleInfo template after implementing
 //       the IR version.
 LLVM_ABI bool isCycleInvariant(const MachineCycleInfo &CI,
-                               const MachineCycle &Cycle, MachineInstr &I);
+                               const CycleRef &Cycle, MachineInstr &I);
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MaskRay wrote:

done

https://github.com/llvm/llvm-project/pull/210117