[llvm] [BPI] Cache LoopExitBlocks to improve compile time (PR #93451)

[Nikita Popov via llvm-commits]

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@@ -343,6 +343,9 @@ class BranchProbabilityInfo {
   /// Keeps mapping of a loop to estimated weight to enter the loop.
   SmallDenseMap<LoopData, uint32_t> EstimatedLoopWeight;
 
+  /// Keeps mapping of a Loop to its "exit" blocks.
+  SmallDenseMap<LoopData, SmallVector<BasicBlock *, 4>> LoopExitBlocks;
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nikic wrote:

Can this be a local variable in computeEestimateBlockWeight? Just to make it clear that there are no invalidation concerns...

https://github.com/llvm/llvm-project/pull/93451