[llvm] [VPlan] Construct VPlan0 once, share across buildVPlans calls. (NFC) (PR #197276)

[Florian Hahn via llvm-commits]

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@@ -5632,6 +5637,7 @@ void LoopVectorizationPlanner::plan(ElementCount UserVF, unsigned UserIC) {
 
   ElementCount MaxUserVF =
       UserVF.isScalable() ? MaxFactors.ScalableVF : MaxFactors.FixedVF;
+
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fhahn wrote:

dropped thanks

https://github.com/llvm/llvm-project/pull/197276