[llvm] [VPlan] Introduce explicit ExtractFromEnd recipes for live-outs. (PR #100658)

[via llvm-commits]

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@@ -8538,9 +8540,8 @@ static void addUsersInExitBlock(
   // and there is nothing to fix from vector loop; phis should have incoming
   // from scalar loop only.
   if (MiddleVPBB->getNumSuccessors() != 2)
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ayalz wrote:

So non-empty exitingValuesToFix implies two successors; having exit block as the only successor is not considered.

Looking forward following our roadmap, initial VPlan should probably always start with both successors, and optimized later to have a single successor if scalar epilog is required or redundant.

Does empty exitingValuesToFix imply no edge from middle block to exit block, i.e., can such an edge exist w/o any lcssa phi's to fix?

https://github.com/llvm/llvm-project/pull/100658