[llvm] [CodeGen] Optimize ctpop expansion using computeKnownBits (PR #221671)

[via llvm-commits]

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@@ -12246,6 +12244,19 @@ void SelectionDAGISel::LowerArguments(const Function &F) {
           OutVal = DAG.getNode(ISD::AssertNoFPClass, dl, OutVal.getValueType(),
                                OutVal, SDNoFPClass);
         }
+        if (VT.isInteger()) {
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milkHongYe wrote:

I originally added those changes because I thought they would help ctpop and other optimizations use range information. I've now removed them.

https://github.com/llvm/llvm-project/pull/221671