[llvm] [AArch64] Improve index selection for histograms (PR #111150)

[Sam Tebbs via llvm-commits]

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@@ -24079,11 +24080,9 @@ static bool findMoreOptimalIndexType(const MaskedGatherScatterSDNode *N,
 
 static SDValue performMaskedGatherScatterCombine(
     SDNode *N, TargetLowering::DAGCombinerInfo &DCI, SelectionDAG &DAG) {
-  MaskedGatherScatterSDNode *MGS = cast<MaskedGatherScatterSDNode>(N);
-  assert(MGS && "Can only combine gather load or scatter store nodes");
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SamTebbs33 wrote:

We should probably keep this assertion, while changing the message to include histograms. I also agree with MacDue that we don't really need the change that moves the cast downwards.

https://github.com/llvm/llvm-project/pull/111150