[llvm] [InstCombine] Extend bitmask mul combine to handle independent operands (PR #142503)

[Yingwei Zheng via llvm-commits]

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@@ -3659,6 +3666,106 @@ static std::optional<DecomposedBitMaskMul> matchBitmaskMul(Value *V) {
   return std::nullopt;
 }
 
+// (A & N) * C + (A & M) * C -> (A & (N + M)) & C
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dtcxzyw wrote:

Use `///`

https://github.com/llvm/llvm-project/pull/142503