[llvm] [VPlan] Verify scalar types in VPlanVerifier. NFCI (PR #122679)

[Florian Hahn via llvm-commits]

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@@ -195,6 +197,9 @@ bool VPlanVerifier::verifyVPBasicBlock(const VPBasicBlock *VPBB) {
       return false;
     }
     for (const VPValue *V : R.definedValues()) {
+      // Verify that recipes' operands have matching types.
+      TypeInfo.inferScalarType(V);
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fhahn wrote:

IIUC the check here would catch violations via the inference assertions as well as uncovered cases. I think it should be fine to rely on the internal consistency checks and maybe check here that the result is non-null and error if it is null? Not sure if we would ever return nullptr on an uncovered case though.

https://github.com/llvm/llvm-project/pull/122679