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

[via llvm-commits]

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@@ -456,10 +456,17 @@ void VPIRBasicBlock::execute(VPTransformState *State) {
   State->Builder.SetInsertPoint(getIRBasicBlock()->getTerminator());
   executeRecipes(State, getIRBasicBlock());
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ayalz wrote:

Worth explaining that if this VPIRBB has zero or two successors, nothing needs to be done - because the latter should already end with a conditional branch recipe(?), otherwise we now ensure it ends with an unconditional branch with a null destination to be backpatched later(?)

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