[llvm] [LoopVectorize] Use new getUniqueLatchExitBlock routine (PR #108231)

[Florian Hahn via llvm-commits]

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@@ -294,6 +294,10 @@ template <class BlockT, class LoopT> class LoopBase {
   /// Otherwise return null.
   BlockT *getUniqueExitBlock() const;
 
+  /// Return the unique exit block for the latch, or null if there are multiple
+  /// different exit blocks.
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fhahn wrote:

or the latch is not exiting?

https://github.com/llvm/llvm-project/pull/108231