[llvm] [VPlan] Introduce scalar loop header in plan, remove VPLiveOut. (PR #109975)

[Florian Hahn via llvm-commits]

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@@ -1260,10 +1261,12 @@ static void remapOperands(VPBlockBase *Entry, VPBlockBase *NewEntry,
 VPlan *VPlan::duplicate() {
   // Clone blocks.
   VPBasicBlock *NewPreheader = Preheader->clone();
-  const auto &[NewEntry, __] = cloneFrom(Entry);
+  const auto &[NewEntry, __, NewScalarHeader] =
+      cloneFrom(Entry, getScalarHeader());
 
   // Create VPlan, clone live-ins and remap operands in the cloned blocks.
-  auto *NewPlan = new VPlan(NewPreheader, cast<VPBasicBlock>(NewEntry));
+  auto *NewPlan =
+      new VPlan(NewPreheader, cast<VPBasicBlock>(NewEntry), NewScalarHeader);
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fhahn wrote:

Will do separately, thanks!

https://github.com/llvm/llvm-project/pull/109975