[llvm] [InstCombine] simplify average of lsb (PR #95684)

[via llvm-commits]

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@@ -1284,6 +1284,14 @@ Instruction *InstCombinerImpl::visitLShr(BinaryOperator &I) {
     return NewSub;
   }
 
+  // ((X % 2) + (Y % 2)) / 2 --> (X & Y & 1)
+  if (match(Op0,
+            m_Add(m_And(m_Value(X), m_One()), m_And(m_Value(Y), m_One()))) &&
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c8ef wrote:

Sounds like a good idea. I'll give it a try.

https://github.com/llvm/llvm-project/pull/95684