[llvm] [CodeGen][NPM] Port MachinePipeliner to NPM (PR #221676)

[Vikram Hegde via llvm-commits]

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@@ -73,14 +75,17 @@ struct MachinePipelinerPolicy {
 
 /// The main class in the implementation of the target independent
 /// software pipeliner pass.
-class LLVM_ABI MachinePipeliner : public MachineFunctionPass {
+class LLVM_ABI MachinePipeliner {
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vikramRH wrote:

Done. Had to decouple the MachinePipeliner and SwingSchedulerDAG in the process which is a better design anyway.

https://github.com/llvm/llvm-project/pull/221676