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

[Luke Lau via llvm-commits]

================
@@ -5108,8 +5111,6 @@ InstructionCost LoopVectorizationCostModel::expectedCost(ElementCount VF) {
     // unconditionally executed. For the scalar case, we may not always execute
     // the predicated block, if it is an if-else block. Thus, scale the block's
     // cost by the probability of executing it.
-    // getPredBlockCostDivisor will return 1 for blocks that are only predicated
----------------
lukel97 wrote:

Added back in 6ee702b1052b6a14dd969f50297d842a31fa959a

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