[llvm] [ARM] Update IsRestored for LR based on all returns (PR #82745)

[Florian Hahn via llvm-commits]

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@@ -59,6 +59,7 @@ class ARMFrameLowering : public TargetFrameLowering {
   void determineCalleeSaves(MachineFunction &MF, BitVector &SavedRegs,
                             RegScavenger *RS) const override;
 
+  void updateLRRestored(MachineFunction &MF) const;
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fhahn wrote:

I might be missing something, but making it a static member of `ARMFrameLowering` should allow it to be called using `ARMFrameLowering::updateLRRestored(Fn);` in `ARMLoadStoreOptimizer`

https://github.com/llvm/llvm-project/pull/82745