[llvm] [NFC] Various Cleanup in StackColoring, StackSlotColoring, LiveStacks (PR #143931)

[Matt Arsenault via llvm-commits]

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@@ -900,6 +931,17 @@ bool StackColoring::removeAllMarkers() {
   }
   Markers.clear();
 
+  for (MachineBasicBlock &MBB : *MF) {
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arsenm wrote:

More than a cleanup? 

https://github.com/llvm/llvm-project/pull/143931