[llvm] [VPlan] Fix LastActiveLane assertion on scalar VF (PR #167897)

[Luke Lau via llvm-commits]

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@@ -46,6 +46,12 @@ VPValue *vputils::getOrCreateVPValueForSCEVExpr(VPlan &Plan, const SCEV *Expr) {
   return Expanded;
 }
 
+static inline auto m_CanonicalScalarIVSteps(const VPlan &Plan) {
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lukel97 wrote:

Yup, turned it into a variable in c0a70672c2a9f64b4efcc71ee786eb2234f9261e

https://github.com/llvm/llvm-project/pull/167897