[llvm] [LoopVectorize] Teach LoopVectorizationLegality about more early exits (PR #107004)

[Florian Hahn via llvm-commits]

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@@ -1442,6 +1487,126 @@ bool LoopVectorizationLegality::canVectorizeLoopNestCFG(
   return Result;
 }
 
+bool LoopVectorizationLegality::isVectorizableEarlyExitLoop() {
+  // At least one of the exiting blocks must be the latch.
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fhahn wrote:

Below just checks if there's a latch, not if it is exiting?

https://github.com/llvm/llvm-project/pull/107004