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diff --git a/llvm/lib/Object/RecordStreamer.h b/llvm/lib/Object/RecordStreamer.h
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+++ b/llvm/lib/Object/RecordStreamer.h
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+//===- RecordStreamer.h - Record asm defined and used symbols ---*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_OBJECT_RECORDSTREAMER_H
+#define LLVM_LIB_OBJECT_RECORDSTREAMER_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/MC/MCDirectives.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/Support/SMLoc.h"
+#include <vector>
+
+namespace llvm {
+
+class GlobalValue;
+class Module;
+
+class RecordStreamer : public MCStreamer {
+public:
+  enum State { NeverSeen, Global, Defined, DefinedGlobal, DefinedWeak, Used,
+               UndefinedWeak};
+
+private:
+  const Module &M;
+  StringMap<State> Symbols;
+  // Map of aliases created by .symver directives, saved so we can update
+  // their symbol binding after parsing complete. This maps from each
+  // aliasee to its list of aliases.
+  DenseMap<const MCSymbol *, std::vector<StringRef>> SymverAliasMap;
+
+  /// Get the state recorded for the given symbol.
+  State getSymbolState(const MCSymbol *Sym);
+
+  void markDefined(const MCSymbol &Symbol);
+  void markGlobal(const MCSymbol &Symbol, MCSymbolAttr Attribute);
+  void markUsed(const MCSymbol &Symbol);
+  void visitUsedSymbol(const MCSymbol &Sym) override;
+
+public:
+  RecordStreamer(MCContext &Context, const Module &M);
+
+  void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override;
+  void EmitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
+  void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) override;
+  bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override;
+  void EmitZerofill(MCSection *Section, MCSymbol *Symbol, uint64_t Size,
+                    unsigned ByteAlignment, SMLoc Loc = SMLoc()) override;
+  void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
+                        unsigned ByteAlignment) override;
+
+  // Ignore COFF-specific directives; we do not need any information from them,
+  // but the default implementation of these methods crashes, so we override
+  // them with versions that do nothing.
+  void BeginCOFFSymbolDef(const MCSymbol *Symbol) override {}
+  void EmitCOFFSymbolStorageClass(int StorageClass) override {}
+  void EmitCOFFSymbolType(int Type) override {}
+  void EndCOFFSymbolDef() override {}
+
+  /// Record .symver aliases for later processing.
+  void emitELFSymverDirective(StringRef AliasName,
+                              const MCSymbol *Aliasee) override;
+
+  // Emit ELF .symver aliases and ensure they have the same binding as the
+  // defined symbol they alias with.
+  void flushSymverDirectives();
+
+  // Symbols iterators
+  using const_iterator = StringMap<State>::const_iterator;
+  const_iterator begin();
+  const_iterator end();
+
+  // SymverAliasMap iterators
+  using const_symver_iterator = decltype(SymverAliasMap)::const_iterator;
+  iterator_range<const_symver_iterator> symverAliases();
+};
+
+} // end namespace llvm
+
+#endif // LLVM_LIB_OBJECT_RECORDSTREAMER_H