[llvm] [VPlan] Use BlockFrequencyInfo in getPredBlockCostDivisor (PR #158690)

[Florian Hahn via llvm-commits]

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@@ -1729,6 +1722,11 @@ class LoopVectorizationCostModel {
   /// Interface to emit optimization remarks.
   OptimizationRemarkEmitter *ORE;
 
+  /// A function to lazily fetch BlockFrequencyInfo. This avoids computing it
+  /// unless necessary, e.g. when the loop isn't legal to vectorize or when
+  /// there is no predication.
+  std::function<BlockFrequencyInfo *()> GetBFI;
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fhahn wrote:

Not sure if it is worth it, but we could avoid repeated (indirect) calls to the lambda if we cache BFI ourselves instead of always going through the lambda + pass manager caching.

https://github.com/llvm/llvm-project/pull/158690