[llvm] [InlineCost] Consider the default branch when calculating cost (PR #77856)

[Matt Arsenault via llvm-commits]

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@@ -1153,6 +1154,7 @@ class InlineCostFeaturesAnalyzer final : public CallAnalyzer {
   // heuristics in the ML inliner.
   static constexpr int JTCostMultiplier = 4;
   static constexpr int CaseClusterCostMultiplier = 2;
+  static constexpr int SwitchDefaultDestCostMultiplier = 2;
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arsenm wrote:

Defined this constant but hardcoded 2 above?

https://github.com/llvm/llvm-project/pull/77856