[llvm] [SelectionDAG] Preserver poison for abs INT_MIN lowering (PR #183851)

[Nikita Popov via llvm-commits]

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@@ -746,6 +746,10 @@ enum NodeType {
   /// is performed.
   ABS,
 
+  /// ABS with an undefined result for INT_MIN. This corresponds to
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nikic wrote:

```suggestion
  /// ABS with a poison result for INT_MIN. This corresponds to
```

https://github.com/llvm/llvm-project/pull/183851