[llvm] [SDAG] Select _, X, X -> X (PR #173989)

[via llvm-commits]

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@@ -13383,11 +13383,9 @@ static SDValue combineVSelectWithAllOnesOrZeros(SDValue Cond, SDValue TVal,
   if (!IsTAllZero && !IsTAllOne && !IsFAllZero && !IsFAllOne)
     return SDValue();
 
-  // select Cond, 0, 0 → 0
-  if (IsTAllZero && IsFAllZero) {
-    return VT.isFloatingPoint() ? DAG.getConstantFP(0.0, DL, VT)
-                                : DAG.getConstant(0, DL, VT);
-  }
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DaKnig wrote:

my bad, I did not realize.

https://github.com/llvm/llvm-project/pull/173989