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

[Arseniy Obolenskiy via llvm-commits]

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@@ -8,19 +8,16 @@
 //
 // \file
 // This file implements ByteProvider. The purpose of ByteProvider is to provide
-// a map between a target node's byte (byte position is DestOffset) and the
-// source (and byte position) that provides it (in Src and SrcOffset
-// respectively) See CodeGen/SelectionDAG/DAGCombiner.cpp MatchLoadCombine
+// a map between a byte of a target node and the source that provides it.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CODEGEN_BYTEPROVIDER_H
 #define LLVM_CODEGEN_BYTEPROVIDER_H
 
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/Support/DataTypes.h"
+#include "llvm/ADT/STLFunctionalExtras.h"
+#include "llvm/CodeGen/SelectionDAGNodes.h"
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aobolensk wrote:

returned the header back

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