[llvm] [NewPM][CodeGen][llc] Add NPM support (PR #70922)

[Arthur Eubanks via llvm-commits]

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@@ -506,6 +506,9 @@ static void registerPartialPipelineCallback(PassInstrumentationCallbacks &PIC,
   unsigned StopBeforeInstanceNum = 0;
   unsigned StopAfterInstanceNum = 0;
 
+  bool IsStopBeforeMachinePass = false;
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aeubanks wrote:

this patch is doing too much at once, please split out the stop before/after to a separate change

https://github.com/llvm/llvm-project/pull/70922