[llvm] [DAGCombiner] Share byte provider steps with AMDGPU target (PR #221959)

[Matt Arsenault via llvm-commits]

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@@ -78,6 +75,46 @@ template <typename ISelOp> class ByteProvider {
            Other.SrcOffset == SrcOffset;
   }
 };
+
+/// Visits both operands even once one answers, because \p Recurse may have
+/// side effects (DAGCombiner accumulates an and mask there).
+template <typename ISelOp, typename RecurseT>
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arsenm wrote:

I don't understand why this is templatized, particularly ISelOp. Is this just SDNode vs. SDValue *? SDValue is the correct type 

https://github.com/llvm/llvm-project/pull/221959