[llvm] [llvm] Support multiple save/restore points in mir (PR #119357)

[Elizaveta Noskova via llvm-commits]

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@@ -558,7 +564,11 @@ static void updateLiveness(MachineFunction &MF) {
   SmallPtrSet<MachineBasicBlock *, 8> Visited;
   SmallVector<MachineBasicBlock *, 8> WorkList;
   MachineBasicBlock *Entry = &MF.front();
-  MachineBasicBlock *Save = MFI.getSavePoint();
+
+  assert(MFI.getSavePoints().size() < 2 &&
+         "MFI can't contain multiple save points!");
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enoskova-sc wrote:

addressed

https://github.com/llvm/llvm-project/pull/119357