[llvm] [VPlan] Implement VPWidenCastRecipe::computeCost(). (NFCI) (PR #111339)

[Florian Hahn via llvm-commits]

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@@ -7258,12 +7258,29 @@ LoopVectorizationPlanner::precomputeCosts(VPlan &Plan, ElementCount VF,
     const auto &ChainOps = RdxDesc.getReductionOpChain(RedPhi, OrigLoop);
     SetVector<Instruction *> ChainOpsAndOperands(ChainOps.begin(),
                                                  ChainOps.end());
+    auto isZExtOrSExt = [](const unsigned Opcode) -> bool {
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fhahn wrote:

```suggestion
    auto IsZExtOrSExt = [](const unsigned Opcode) -> bool {
```

https://github.com/llvm/llvm-project/pull/111339