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

[via llvm-commits]

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@@ -1135,7 +1135,14 @@ class VPPhiAccessors {
   const VPBasicBlock *getIncomingBlock(unsigned Idx) const;
 
   /// Returns the number of incoming values, also number of incoming blocks.
-  unsigned getNumIncoming() const { return getAsRecipe()->getNumOperands(); }
+  /// Note that at the moment, VPWidenIntOrFpInductionRecipes only have a single
+  /// incoming value, its start value.
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ayalz wrote:

Better have VPWidenIntOrFpInductionRecipe override a virtual getNumIncoming()?

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