[llvm] [AMDGPU] 32-bit ABS is a legal DAG node (PR #163907)

[Shilei Tian via llvm-commits]

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@@ -14945,6 +14945,13 @@ SDValue SITargetLowering::performMinMaxCombine(SDNode *N,
     }
   }
 
+  // max(x, neg(x)) -> abs(x)
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shiltian wrote:

Can we do this in the generic part?

https://github.com/llvm/llvm-project/pull/163907