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diff --git a/include/llvm/CodeGen/SelectionDAGAddressAnalysis.h b/include/llvm/CodeGen/SelectionDAGAddressAnalysis.h
new file mode 100644
index 0000000000000..d82ab7d647e75
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+++ b/include/llvm/CodeGen/SelectionDAGAddressAnalysis.h
@@ -0,0 +1,64 @@
+//===-- llvm/CodeGen/SelectionDAGAddressAnalysis.h  ------- DAG Address Analysis
+//---*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+
+#ifndef LLVM_CODEGEN_SELECTIONDAGADDRESSANALYSIS_H
+#define LLVM_CODEGEN_SELECTIONDAGADDRESSANALYSIS_H
+
+#include "llvm/CodeGen/ISDOpcodes.h"
+#include "llvm/CodeGen/SelectionDAG.h"
+#include "llvm/CodeGen/SelectionDAGNodes.h"
+
+namespace llvm {
+/// Helper struct to parse and store a memory address as base + index + offset.
+/// We ignore sign extensions when it is safe to do so.
+/// The following two expressions are not equivalent. To differentiate we need
+/// to store whether there was a sign extension involved in the index
+/// computation.
+///  (load (i64 add (i64 copyfromreg %c)
+///                 (i64 signextend (add (i8 load %index)
+///                                      (i8 1))))
+/// vs
+///
+/// (load (i64 add (i64 copyfromreg %c)
+///                (i64 signextend (i32 add (i32 signextend (i8 load %index))
+///                                         (i32 1)))))
+class BaseIndexOffset {
+private:
+  SDValue Base;
+  SDValue Index;
+  int64_t Offset;
+  bool IsIndexSignExt;
+
+public:
+  BaseIndexOffset() : Offset(0), IsIndexSignExt(false) {}
+
+  BaseIndexOffset(SDValue Base, SDValue Index, int64_t Offset,
+                  bool IsIndexSignExt)
+      : Base(Base), Index(Index), Offset(Offset),
+        IsIndexSignExt(IsIndexSignExt) {}
+
+  SDValue getBase() { return Base; }
+  SDValue getIndex() { return Index; }
+
+  bool equalBaseIndex(BaseIndexOffset &Other, const SelectionDAG &DAG) {
+    int64_t Off;
+    return equalBaseIndex(Other, DAG, Off);
+  }
+
+  bool equalBaseIndex(BaseIndexOffset &Other, const SelectionDAG &DAG,
+                      int64_t &Off);
+
+  /// Parses tree in Ptr for base, index, offset addresses.
+  static BaseIndexOffset match(SDValue Ptr);
+};
+} // namespace llvm
+
+#endif