[llvm] [CmpInstAnalysis] Return decomposed bit test as struct (NFC) (PR #109819)

[Yingwei Zheng via llvm-commits]

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@@ -2465,10 +2465,16 @@ static bool detectShiftUntilBitTestIdiom(Loop *CurLoop, Value *&BaseX,
   };
   auto MatchDecomposableConstantBitMask = [&]() {
     APInt Mask;
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dtcxzyw wrote:

It is unused now.


https://github.com/llvm/llvm-project/pull/109819