[llvm] [VPlan] Materialize constant vector trip counts before final opts. (PR #142309)

[via llvm-commits]

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@@ -3120,6 +3115,29 @@ void VPlanTransforms::materializeBroadcasts(VPlan &Plan) {
   }
 }
 
+void VPlanTransforms::materializeVectorTripCount(
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ayalz wrote:

```suggestion
void VPlanTransforms::materializeConstantVectorTripCount(
```
?

https://github.com/llvm/llvm-project/pull/142309