[llvm] [VPlan] Verify dominance for incoming values of phi-like recipes. (PR #124838)

[via llvm-commits]

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@@ -207,24 +213,69 @@ bool VPlanVerifier::verifyVPBasicBlock(const VPBasicBlock *VPBB) {
 
       for (const VPUser *U : V->users()) {
         auto *UI = cast<VPRecipeBase>(U);
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ayalz wrote:

unrelated nit:
```suggestion
        auto *UR = cast<VPRecipeBase>(U);
```

https://github.com/llvm/llvm-project/pull/124838