[llvm] [InstCombine] Simplification for (-a * b) / (a * b). (PR #71768)

[Yingwei Zheng via llvm-commits]

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@@ -1544,6 +1544,13 @@ Instruction *InstCombinerImpl::visitSDiv(BinaryOperator &I) {
     }
   }
 
+  // -(X * Y) / (X * Y) --> -1
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dtcxzyw wrote:

Please move the logic into `isKnownNegation`.

https://github.com/llvm/llvm-project/pull/71768