[llvm] [MachineBasicBlock] Fix use after free in SplitCriticalEdge (PR #66188)

[Jay Foad via llvm-commits]

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@@ -693,7 +693,8 @@ class MachineBasicBlock
   /// layout was modified.  If the block previously fell through to that block,
   /// it may now need a branch. If it previously branched to another block, it
   /// may now be able to fallthrough to the current layout successor.
-  void updateTerminator(MachineBasicBlock *PreviousLayoutSuccessor);
+  void updateTerminator(MachineBasicBlock *PreviousLayoutSuccessor,
+                        SlotIndexes *Indexes = nullptr);
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jayfoad wrote:

Really ought to mention `\p SlotIndexes` in the doxygen comments, here and in TargetInstrInfo.

https://github.com/llvm/llvm-project/pull/66188