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diff --git a/llvm/lib/CodeGen/AsmPrinter/DIEHash.h b/llvm/lib/CodeGen/AsmPrinter/DIEHash.h
new file mode 100644
index 000000000000..2e49514c98be
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+++ b/llvm/lib/CodeGen/AsmPrinter/DIEHash.h
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+//===-- llvm/CodeGen/DIEHash.h - Dwarf Hashing Framework -------*- C++ -*--===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for DWARF4 hashing of DIEs.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DIEHASH_H
+#define LLVM_LIB_CODEGEN_ASMPRINTER_DIEHASH_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/CodeGen/DIE.h"
+#include "llvm/Support/MD5.h"
+
+namespace llvm {
+
+class AsmPrinter;
+class CompileUnit;
+
+/// An object containing the capability of hashing and adding hash
+/// attributes onto a DIE.
+class DIEHash {
+  // Collection of all attributes used in hashing a particular DIE.
+  struct DIEAttrs {
+#define HANDLE_DIE_HASH_ATTR(NAME) DIEValue NAME;
+#include "DIEHashAttributes.def"
+  };
+
+public:
+  DIEHash(AsmPrinter *A = nullptr) : AP(A) {}
+
+  /// Computes the CU signature.
+  uint64_t computeCUSignature(StringRef DWOName, const DIE &Die);
+
+  /// Computes the type signature.
+  uint64_t computeTypeSignature(const DIE &Die);
+
+  // Helper routines to process parts of a DIE.
+private:
+  /// Adds the parent context of \param Parent to the hash.
+  void addParentContext(const DIE &Parent);
+
+  /// Adds the attributes of \param Die to the hash.
+  void addAttributes(const DIE &Die);
+
+  /// Computes the full DWARF4 7.27 hash of the DIE.
+  void computeHash(const DIE &Die);
+
+  // Routines that add DIEValues to the hash.
+public:
+  /// Adds \param Value to the hash.
+  void update(uint8_t Value) { Hash.update(Value); }
+
+  /// Encodes and adds \param Value to the hash as a ULEB128.
+  void addULEB128(uint64_t Value);
+
+  /// Encodes and adds \param Value to the hash as a SLEB128.
+  void addSLEB128(int64_t Value);
+
+private:
+  /// Adds \param Str to the hash and includes a NULL byte.
+  void addString(StringRef Str);
+
+  /// Collects the attributes of DIE \param Die into the \param Attrs
+  /// structure.
+  void collectAttributes(const DIE &Die, DIEAttrs &Attrs);
+
+  /// Hashes the attributes in \param Attrs in order.
+  void hashAttributes(const DIEAttrs &Attrs, dwarf::Tag Tag);
+
+  /// Hashes the data in a block like DIEValue, e.g. DW_FORM_block or
+  /// DW_FORM_exprloc.
+  void hashBlockData(const DIE::const_value_range &Values);
+
+  /// Hashes the contents pointed to in the .debug_loc section.
+  void hashLocList(const DIELocList &LocList);
+
+  /// Hashes an individual attribute.
+  void hashAttribute(const DIEValue &Value, dwarf::Tag Tag);
+
+  /// Hashes an attribute that refers to another DIE.
+  void hashDIEEntry(dwarf::Attribute Attribute, dwarf::Tag Tag,
+                    const DIE &Entry);
+
+  /// Hashes a reference to a named type in such a way that is
+  /// independent of whether that type is described by a declaration or a
+  /// definition.
+  void hashShallowTypeReference(dwarf::Attribute Attribute, const DIE &Entry,
+                                StringRef Name);
+
+  /// Hashes a reference to a previously referenced type DIE.
+  void hashRepeatedTypeReference(dwarf::Attribute Attribute,
+                                 unsigned DieNumber);
+
+  void hashNestedType(const DIE &Die, StringRef Name);
+
+private:
+  MD5 Hash;
+  AsmPrinter *AP;
+  DenseMap<const DIE *, unsigned> Numbering;
+};
+}
+
+#endif