[llvm] [LCSSA] Cache the loop exit blocks across recursive analysis (NFC) (PR #101087)

[Teresa Johnson via llvm-commits]

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@@ -374,6 +391,8 @@ bool llvm::formLCSSA(Loop &L, const DominatorTree &DT, const LoopInfo *LI,
 
   SmallVector<BasicBlock *, 8> ExitBlocks;
   L.getExitBlocks(ExitBlocks);
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teresajohnson wrote:

Did a little bit more cleanup here to make this more closely match the other getExitBlocks() callsite and save and pass down the ExitBlocks as a SmallVectorImpl

https://github.com/llvm/llvm-project/pull/101087