[llvm] [LV] Consolidate shouldOptimizeForSize and remove unused BFI/PSI. NFC (PR #168697)

[Florian Hahn via llvm-commits]

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@@ -720,9 +717,9 @@ class LoopVectorizationLegality {
   /// Hold potentially faulting loads.
   SmallPtrSet<const Instruction *, 4> PotentiallyFaultingLoads;
 
-  /// BFI and PSI are used to check for profile guided size optimizations.
-  BlockFrequencyInfo *BFI;
-  ProfileSummaryInfo *PSI;
+  /// Whether or not we can assume SCEV overflow doesn't occur and generate
+  /// runtime checks later.
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fhahn wrote:

```suggestion
  /// Whether or not creating SCEV predicates is allowed.
```

Might be simpler to just stay this controls whether SCEV predicates are allowed or not


https://github.com/llvm/llvm-project/pull/168697