[llvm] [VPlan] Model branch cond to enter scalar epilogue in VPlan. (PR #92651)

[Florian Hahn via llvm-commits]

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@@ -34,8 +34,11 @@ void VPlanTransforms::VPInstructionsToVPRecipes(
     ScalarEvolution &SE, const TargetLibraryInfo &TLI) {
 
   ReversePostOrderTraversal<VPBlockDeepTraversalWrapper<VPBlockBase *>> RPOT(
-      Plan->getEntry());
+      Plan->getVectorLoopRegion());
   for (VPBasicBlock *VPBB : VPBlockUtils::blocksOnly<VPBasicBlock>(RPOT)) {
+    // Skip blocks outside region
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fhahn wrote:

Unfortunately yes. The way GraphTraits work, I don't think theres' a way to avoid 'escaping' as we can't access the starting node when constructing the iterators for each visited node :(

https://github.com/llvm/llvm-project/pull/92651