[llvm] [VPlan] Delay adding canonical IV increment and exit branches. (PR #82270)

[via llvm-commits]

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@@ -142,7 +143,7 @@ static bool verifyBlock(const VPBlockBase *VPB, const VPDominatorTree &VPDT) {
   if (VPB->getNumSuccessors() > 1 ||
       (VPBB && VPBB->getParent() && VPBB->isExiting() &&
        !VPBB->getParent()->isReplicator())) {
-    if (!VPBB || !VPBB->getTerminator()) {
+    if (!IsAbstract && (!VPBB || !VPBB->getTerminator())) {
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ayalz wrote:

Perhaps rather than a global  parameter, `Is[RegionBackBranch]Abstract` is more a property of the parental region - whether it ends with an explicit terminating branch or not - the latter applying to both replicating regions and non-replicating regions in "abstract loop-control" state.

https://github.com/llvm/llvm-project/pull/82270