[llvm] [LV][NFC] Refactor structures used to maintain uncountable exit info (PR #123219)

[David Sherwood via llvm-commits]

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@@ -391,25 +391,22 @@ class LoopVectorizationLegality {
 
   /// Returns true if the loop has an uncountable early exit, i.e. an
   /// uncountable exit that isn't the latch block.
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david-arm wrote:

Done

https://github.com/llvm/llvm-project/pull/123219