[llvm] [SelectionDAG]: Deduce known bits from SMIN and SMAX (PR #85722)

[via llvm-commits]

================
@@ -4017,6 +4015,16 @@ KnownBits SelectionDAG::computeKnownBits(SDValue Op, const APInt &DemandedElts,
       }
     }
 
+    // For SMIN, if CstHigh is negative we know the result will be
----------------
AtariDreams wrote:

smin_known_zero_2

it mirrors smax's logic

https://github.com/llvm/llvm-project/pull/85722