[llvm] [RegisterCoalescer]: Try inflated RC for coalescing (PR #130870)

[Matt Arsenault via llvm-commits]

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@@ -456,6 +456,30 @@ static bool isSplitEdge(const MachineBasicBlock *MBB) {
   return true;
 }
 
+static const TargetRegisterClass *
+getLargestLegalRegClass(Register Reg, const MachineFunction *MF,
+                        const MachineRegisterInfo &MRI) {
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arsenm wrote:

This is mostly copy paste from the MRI function, can you refactor it there to expose this 

https://github.com/llvm/llvm-project/pull/130870