[llvm] [VPlan] Connect Entry to scalar preheader during initial construction. (PR #140132)

[via llvm-commits]

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@@ -490,7 +490,7 @@ class InnerLoopVectorizer {
         MinProfitableTripCount(MinProfitableTripCount), UF(UnrollFactor),
         Builder(PSE.getSE()->getContext()), Cost(CM), BFI(BFI), PSI(PSI),
         RTChecks(RTChecks), Plan(Plan),
-        VectorPHVPB(Plan.getEntry()->getSingleSuccessor()) {}
+        VectorPHVPB(Plan.getVectorLoopRegion()->getSinglePredecessor()) {}
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ayalz wrote:

Note that ILV now depends on HCFG here, and elsewhere. Maybe better to retrieve the first hierarchical predecessor of first header block, to relax this dependence, possibly as follow up.

https://github.com/llvm/llvm-project/pull/140132