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

[Florian Hahn via llvm-commits]

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@@ -1653,7 +1652,7 @@ bool LoopVectorizationLegality::isVectorizableEarlyExitLoop() {
         assert(!TheLoop->contains(Succs[1]));
         ExitBlock = Succs[1];
       }
-      UncountableExitBlocks.push_back(ExitBlock);
+      UncountableEdges.push_back({BB, ExitBlock});
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fhahn wrote:

Simpler to exit here once we hit more than one, now that we only store one?

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