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

[Sam Tebbs via llvm-commits]

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@@ -6727,6 +6756,11 @@ bool VPCostContext::skipCostComputation(Instruction *UI, bool IsVector) const {
          SkipCostComputation.contains(UI);
 }
 
+unsigned VPCostContext::getPredBlockCostDivisor(
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SamTebbs33 wrote:

Is this needed when the caller could just use `Ctx.CM.getPredBlockCostDivisor`?

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