[llvm] [LV][NFC] Clean up tail-folding check for early-exit loops (PR #133931)

[Florian Hahn via llvm-commits]

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@@ -4032,14 +4016,17 @@ LoopVectorizationCostModel::computeMaxVF(ElementCount UserVF, unsigned UserIC) {
   }
 
   auto NoScalarEpilogueNeeded = [this, &UserIC](unsigned MaxVF) {
+    if (TheLoop->getExitingBlock() != TheLoop->getLoopLatch() &&
+        !Legal->hasUncountableEarlyExit())
+      return false;
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fhahn wrote:

Could you document what this is checking? It's not entirely obvious from just looking at the condition

https://github.com/llvm/llvm-project/pull/133931