[llvm] [DAGCombiner] Fix scalarizeExtractedBinOp for some SETCC cases (PR #123071)

[David Sherwood via llvm-commits]

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@@ -22809,7 +22809,8 @@ static SDValue scalarizeExtractedBinOp(SDNode *ExtElt, SelectionDAG &DAG,
 
   EVT ResVT = ExtElt->getValueType(0);
   if (Opc == ISD::SETCC &&
-      (ResVT != Vec.getValueType().getVectorElementType() || LegalTypes))
+      (ResVT != Vec.getValueType().getVectorElementType() || ResVT != MVT::i1 ||
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david-arm wrote:

Rather than bail out, I've just added support for detecting the additional sign-extend required.

https://github.com/llvm/llvm-project/pull/123071