[llvm] [CodeGen][NewPM] Port OptimizePHIs to NPM (PR #113433)

[Akshat Oke via llvm-commits]

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@@ -33,47 +34,65 @@ STATISTIC(NumDeadPHICycles, "Number of dead PHI cycles");
 
 namespace {
 
-  class OptimizePHIs : public MachineFunctionPass {
-    MachineRegisterInfo *MRI = nullptr;
-    const TargetInstrInfo *TII = nullptr;
+class OptimizePHIs {
+  MachineRegisterInfo *MRI = nullptr;
+  const TargetInstrInfo *TII = nullptr;
 
-  public:
-    static char ID; // Pass identification
+public:
+  bool run(MachineFunction &Fn);
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optimisan wrote:

It is from the existing legacy pass

https://github.com/llvm/llvm-project/pull/113433