[llvm] [LoopInterchange] Stop performing unprofitable interchange (PR #127473)

[Sjoerd Meijer via llvm-commits]

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@@ -388,6 +387,8 @@ class LoopInterchangeProfitability {
 
   /// Interface to emit optimization remarks.
   OptimizationRemarkEmitter *ORE;
+
+  const std::optional<CostMapTy> &CostMap;
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sjoerdmeijer wrote:

Nit: a comment explaining what this is exactly capturing would be good. I.e., it's a map of:

   `Loop` -> `[index, cost]`?

https://github.com/llvm/llvm-project/pull/127473