Index: include/llvm/MC/MCAsmMacro.h
===================================================================
--- /dev/null
+++ include/llvm/MC/MCAsmMacro.h
@@ -0,0 +1,42 @@
+//===- MCAsmMacro.h - Assembly Macros ---------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCASMMACRO_H
+#define LLVM_MC_MCASMMACRO_H
+
+#include "llvm/MC/MCParser/MCAsmLexer.h"
+#include <cstddef>
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace llvm {
+
+  struct MCAsmMacroParameter {
+    StringRef Name;
+    std::vector<AsmToken> Value;
+    bool Required = false;
+    bool Vararg = false;
+
+    MCAsmMacroParameter() = default;
+  };
+
+  typedef std::vector<MCAsmMacroParameter> MCAsmMacroParameters;
+  struct MCAsmMacro {
+    StringRef Name;
+    StringRef Body;
+    MCAsmMacroParameters Parameters;
+
+  public:
+    MCAsmMacro(StringRef N, StringRef B, MCAsmMacroParameters P)
+        : Name(N), Body(B), Parameters(std::move(P)) {}
+  };
+};
+
+#endif
Index: include/llvm/MC/MCContext.h
===================================================================
--- include/llvm/MC/MCContext.h
+++ include/llvm/MC/MCContext.h
@@ -18,6 +18,7 @@
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/BinaryFormat/Dwarf.h"
+#include "llvm/MC/MCAsmMacro.h"
 #include "llvm/MC/MCDwarf.h"
 #include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/MC/SectionKind.h"
@@ -269,6 +270,9 @@
                                        unsigned UniqueID,
                                        const MCSymbolELF *Associated);
 
+    /// \brief Map of currently defined macros.
+    StringMap<MCAsmMacro> MacroMap;
+
   public:
     explicit MCContext(const MCAsmInfo *MAI, const MCRegisterInfo *MRI,
                        const MCObjectFileInfo *MOFI,
@@ -620,6 +624,17 @@
     // FIXME: We should really do something about that.
     LLVM_ATTRIBUTE_NORETURN void reportFatalError(SMLoc L,
                                                   const Twine &Msg);
+
+    const MCAsmMacro *lookupMacro(StringRef Name) {
+      StringMap<MCAsmMacro>::iterator I = MacroMap.find(Name);
+      return (I == MacroMap.end()) ? nullptr : &I->getValue();
+    }
+
+    void defineMacro(StringRef Name, MCAsmMacro Macro) {
+      MacroMap.insert(std::make_pair(Name, std::move(Macro)));
+    }
+
+    void undefineMacro(StringRef Name) { MacroMap.erase(Name); }
   };
 
 } // end namespace llvm
Index: lib/MC/MCParser/AsmParser.cpp
===================================================================
--- lib/MC/MCParser/AsmParser.cpp
+++ lib/MC/MCParser/AsmParser.cpp
@@ -84,27 +84,6 @@
 typedef std::vector<AsmToken> MCAsmMacroArgument;
 typedef std::vector<MCAsmMacroArgument> MCAsmMacroArguments;
 
-struct MCAsmMacroParameter {
-  StringRef Name;
-  MCAsmMacroArgument Value;
-  bool Required = false;
-  bool Vararg = false;
-
-  MCAsmMacroParameter() = default;
-};
-
-typedef std::vector<MCAsmMacroParameter> MCAsmMacroParameters;
-
-struct MCAsmMacro {
-  StringRef Name;
-  StringRef Body;
-  MCAsmMacroParameters Parameters;
-
-public:
-  MCAsmMacro(StringRef N, StringRef B, MCAsmMacroParameters P)
-      : Name(N), Body(B), Parameters(std::move(P)) {}
-};
-
 /// \brief Helper class for storing information about an active macro
 /// instantiation.
 struct MacroInstantiation {
@@ -165,9 +144,6 @@
   /// addDirectiveHandler.
   StringMap<ExtensionDirectiveHandler> ExtensionDirectiveMap;
 
-  /// \brief Map of currently defined macros.
-  StringMap<MCAsmMacro> MacroMap;
-
   /// \brief Stack of active macro instantiations.
   std::vector<MacroInstantiation*> ActiveMacros;
 
@@ -309,17 +285,6 @@
   /// \brief Control a flag in the parser that enables or disables macros.
   void setMacrosEnabled(bool Flag) {MacrosEnabledFlag = Flag;}
 
-  /// \brief Lookup a previously defined macro.
-  /// \param Name Macro name.
-  /// \returns Pointer to macro. NULL if no such macro was defined.
-  const MCAsmMacro* lookupMacro(StringRef Name);
-
-  /// \brief Define a new macro with the given name and information.
-  void defineMacro(StringRef Name, MCAsmMacro Macro);
-
-  /// \brief Undefine a macro. If no such macro was defined, it's a no-op.
-  void undefineMacro(StringRef Name);
-
   /// \brief Are we inside a macro instantiation?
   bool isInsideMacroInstantiation() {return !ActiveMacros.empty();}
 
@@ -1842,7 +1807,7 @@
 
   // If macros are enabled, check to see if this is a macro instantiation.
   if (areMacrosEnabled())
-    if (const MCAsmMacro *M = lookupMacro(IDVal)) {
+    if (const MCAsmMacro *M = getContext().lookupMacro(IDVal)) {
       return handleMacroEntry(M, IDLoc);
     }
 
@@ -2721,17 +2686,6 @@
   return TokError("too many positional arguments");
 }
 
-const MCAsmMacro *AsmParser::lookupMacro(StringRef Name) {
-  StringMap<MCAsmMacro>::iterator I = MacroMap.find(Name);
-  return (I == MacroMap.end()) ? nullptr : &I->getValue();
-}
-
-void AsmParser::defineMacro(StringRef Name, MCAsmMacro Macro) {
-  MacroMap.insert(std::make_pair(Name, std::move(Macro)));
-}
-
-void AsmParser::undefineMacro(StringRef Name) { MacroMap.erase(Name); }
-
 bool AsmParser::handleMacroEntry(const MCAsmMacro *M, SMLoc NameLoc) {
   // Arbitrarily limit macro nesting depth (default matches 'as'). We can
   // eliminate this, although we should protect against infinite loops.
@@ -4274,7 +4228,7 @@
     eatToEndOfStatement();
   }
 
-  if (lookupMacro(Name)) {
+  if (getContext().lookupMacro(Name)) {
     return Error(DirectiveLoc, "macro '" + Name + "' is already defined");
   }
 
@@ -4282,7 +4236,7 @@
   const char *BodyEnd = EndToken.getLoc().getPointer();
   StringRef Body = StringRef(BodyStart, BodyEnd - BodyStart);
   checkForBadMacro(DirectiveLoc, Name, Body, Parameters);
-  defineMacro(Name, MCAsmMacro(Name, Body, std::move(Parameters)));
+  getContext().defineMacro(Name, MCAsmMacro(Name, Body, std::move(Parameters)));
   return false;
 }
 
@@ -4441,10 +4395,10 @@
                  "unexpected token in '.purgem' directive"))
     return true;
 
-  if (!lookupMacro(Name))
+  if (!getContext().lookupMacro(Name))
     return Error(DirectiveLoc, "macro '" + Name + "' is not defined");
 
-  undefineMacro(Name);
+  getContext().undefineMacro(Name);
   return false;
 }
 
Index: test/MC/AsmParser/inline_macro_duplication.ll
===================================================================
--- /dev/null
+++ test/MC/AsmParser/inline_macro_duplication.ll
@@ -0,0 +1,9 @@
+; RUN: not llc < %s 2>&1 | FileCheck %s
+
+define void @test() #0 {
+entry:
+  call void asm sideeffect ".macro FOO\0A.endm", "~{dirflag},~{fpsr},~{flags}"() #1
+  call void asm sideeffect ".macro FOO\0A.endm", "~{dirflag},~{fpsr},~{flags}"() #1
+; CHECK: error: macro 'FOO' is already defined
+  ret void
+}