diff --git a/utils/TableGen/X86DisassemblerShared.h b/utils/TableGen/X86DisassemblerShared.h
new file mode 100644
index 0000000..9003cbf
--- /dev/null
+++ b/utils/TableGen/X86DisassemblerShared.h
@@ -0,0 +1,37 @@
+//===- X86DisassemblerShared.h - Emitter shared header ----------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef X86DISASSEMBLERSHARED_H
+#define X86DISASSEMBLERSHARED_H
+
+#include <string>
+
+#define INSTRUCTION_SPECIFIER_FIELDS    \
+  bool                    filtered;     \
+  InstructionContext      insnContext;  \
+  std::string             name;         \
+                                        \
+  InstructionSpecifier() {              \
+    filtered = false;                   \
+    insnContext = IC;                   \
+    name = "";                          \
+    modifierType = MODIFIER_NONE;       \
+    modifierBase = 0;                   \
+    bzero(operands, sizeof(operands));  \
+  }
+
+#define INSTRUCTION_IDS           \
+  InstrUID   instructionIDs[256];
+
+#include "../../lib/Target/X86/Disassembler/X86DisassemblerDecoderCommon.h"
+
+#undef INSTRUCTION_SPECIFIER_FIELDS
+#undef INSTRUCTION_IDS
+
+#endif