[llvm] [VPlan] Return Max from computeCost without underlying instrs. (PR #109708)

[via llvm-commits]

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@@ -293,9 +285,13 @@ InstructionCost VPRecipeBase::cost(ElementCount VF, VPCostContext &Ctx) {
     return 0;
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ayalz wrote:

Note that skipped costs also skip debug dump.

https://github.com/llvm/llvm-project/pull/109708