[llvm] [DAG] Fold (and X, (add (not Y), Z)) -> (and X, (not (sub Y, Z))). (PR #141476)

Simon Pilgrim via llvm-commits llvm-commits at lists.llvm.org
Wed Jun 11 07:05:21 PDT 2025


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@@ -11609,6 +11625,28 @@ SDValue DAGCombiner::foldShiftToAvg(SDNode *N) {
   return DAG.getNode(FloorISD, SDLoc(N), N->getValueType(0), {A, B});
 }
 
+SDValue DAGCombiner::foldBitwiseOpWithNeg(SDNode *N, const SDLoc &DL, EVT VT) {
+  if (!TLI.hasAndNot(SDValue(N, 0)))
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RKSimon wrote:

Sorry I missed this - yes it looks like its a mess. Maybe adding a hasBitwiseLogicNot(Opc, VT) variant first and then moving over as many of the hasAndNot calls as possible?

https://github.com/llvm/llvm-project/pull/141476


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