[llvm] [LV] Move check if any vector insts will be generated to VPlan. (PR #96622)

[via llvm-commits]

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@@ -4929,7 +4970,7 @@ VectorizationFactor LoopVectorizationPlanner::selectVectorizationFactor() {
       LLVM_DEBUG(dbgs() << ".\n");
 #endif
 
-      if (!C.second && !ForceVectorization) {
+      if (!willGenerateVectorInstructions(*P, VF, TTI) && !ForceVectorization) {
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ayalz wrote:

```suggestion
      if (!ForceVectorization && !willGenerateVectorInstructions(*P, VF, TTI)) {
```

https://github.com/llvm/llvm-project/pull/96622