[llvm] [NewPM] Adds a port for AArch64PostCoalescerPass (PR #189520)

[Aiden Grossman via llvm-commits]

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@@ -19,13 +21,18 @@ using namespace llvm;
 
 namespace {
 
-struct AArch64PostCoalescer : public MachineFunctionPass {
-  static char ID;
+struct AArch64PostCoalescerImpl {
+  LiveIntervals &LIS;
+  MachineRegisterInfo *MRI;
 
-  AArch64PostCoalescer() : MachineFunctionPass(ID) {}
+  explicit AArch64PostCoalescerImpl(LiveIntervals &LIS) : LIS(LIS) {}
+  bool run(MachineFunction &MF);
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boomanaiden154 wrote:

Given we only have a single function in the `*Impl` class and we do not need `MRI` to persist between functions, we can probably just turn this into a static (or anonymous namespaced) function?

https://github.com/llvm/llvm-project/pull/189520