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diff --git a/contrib/llvm/include/llvm/MC/MCAsmBackend.h b/contrib/llvm/include/llvm/MC/MCAsmBackend.h
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+++ b/contrib/llvm/include/llvm/MC/MCAsmBackend.h
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+//===-- llvm/MC/MCAsmBackend.h - MC Asm Backend -----------------*- 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_MCASMBACKEND_H
+#define LLVM_MC_MCASMBACKEND_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/MC/MCDirectives.h"
+#include "llvm/MC/MCDwarf.h"
+#include "llvm/MC/MCFixup.h"
+#include "llvm/Support/DataTypes.h"
+#include "llvm/Support/ErrorHandling.h"
+
+namespace llvm {
+class MCAsmLayout;
+class MCAssembler;
+class MCELFObjectTargetWriter;
+struct MCFixupKindInfo;
+class MCFragment;
+class MCInst;
+class MCRelaxableFragment;
+class MCObjectWriter;
+class MCSection;
+class MCValue;
+class raw_ostream;
+
+/// Generic interface to target specific assembler backends.
+class MCAsmBackend {
+  MCAsmBackend(const MCAsmBackend &) = delete;
+  void operator=(const MCAsmBackend &) = delete;
+
+protected: // Can only create subclasses.
+  MCAsmBackend();
+
+  unsigned HasDataInCodeSupport : 1;
+
+public:
+  virtual ~MCAsmBackend();
+
+  /// lifetime management
+  virtual void reset() {}
+
+  /// Create a new MCObjectWriter instance for use by the assembler backend to
+  /// emit the final object file.
+  virtual MCObjectWriter *createObjectWriter(raw_pwrite_stream &OS) const = 0;
+
+  /// Create a new ELFObjectTargetWriter to enable non-standard
+  /// ELFObjectWriters.
+  virtual MCELFObjectTargetWriter *createELFObjectTargetWriter() const {
+    llvm_unreachable("createELFObjectTargetWriter is not supported by asm "
+                     "backend");
+  }
+
+  /// Check whether this target implements data-in-code markers. If not, data
+  /// region directives will be ignored.
+  bool hasDataInCodeSupport() const { return HasDataInCodeSupport; }
+
+  /// \name Target Fixup Interfaces
+  /// @{
+
+  /// Get the number of target specific fixup kinds.
+  virtual unsigned getNumFixupKinds() const = 0;
+
+  /// Get information on a fixup kind.
+  virtual const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const;
+
+  /// Target hook to adjust the literal value of a fixup if necessary.
+  /// IsResolved signals whether the caller believes a relocation is needed; the
+  /// target can modify the value. The default does nothing.
+  virtual void processFixupValue(const MCAssembler &Asm,
+                                 const MCAsmLayout &Layout,
+                                 const MCFixup &Fixup, const MCFragment *DF,
+                                 const MCValue &Target, uint64_t &Value,
+                                 bool &IsResolved) {}
+
+  /// Apply the \p Value for given \p Fixup into the provided data fragment, at
+  /// the offset specified by the fixup and following the fixup kind as
+  /// appropriate.
+  virtual void applyFixup(const MCFixup &Fixup, char *Data, unsigned DataSize,
+                          uint64_t Value, bool IsPCRel) const = 0;
+
+  /// @}
+
+  /// \name Target Relaxation Interfaces
+  /// @{
+
+  /// Check whether the given instruction may need relaxation.
+  ///
+  /// \param Inst - The instruction to test.
+  virtual bool mayNeedRelaxation(const MCInst &Inst) const = 0;
+
+  /// Target specific predicate for whether a given fixup requires the
+  /// associated instruction to be relaxed.
+  virtual bool fixupNeedsRelaxationAdvanced(const MCFixup &Fixup, bool Resolved,
+                                            uint64_t Value,
+                                            const MCRelaxableFragment *DF,
+                                            const MCAsmLayout &Layout) const;
+
+  /// Simple predicate for targets where !Resolved implies requiring relaxation
+  virtual bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
+                                    const MCRelaxableFragment *DF,
+                                    const MCAsmLayout &Layout) const = 0;
+
+  /// Relax the instruction in the given fragment to the next wider instruction.
+  ///
+  /// \param Inst The instruction to relax, which may be the same as the
+  /// output.
+  /// \param [out] Res On return, the relaxed instruction.
+  virtual void relaxInstruction(const MCInst &Inst, MCInst &Res) const = 0;
+
+  /// @}
+
+  /// Returns the minimum size of a nop in bytes on this target. The assembler
+  /// will use this to emit excess padding in situations where the padding
+  /// required for simple alignment would be less than the minimum nop size.
+  ///
+  virtual unsigned getMinimumNopSize() const { return 1; }
+
+  /// Write an (optimal) nop sequence of Count bytes to the given output. If the
+  /// target cannot generate such a sequence, it should return an error.
+  ///
+  /// \return - True on success.
+  virtual bool writeNopData(uint64_t Count, MCObjectWriter *OW) const = 0;
+
+  /// Handle any target-specific assembler flags. By default, do nothing.
+  virtual void handleAssemblerFlag(MCAssemblerFlag Flag) {}
+
+  /// \brief Generate the compact unwind encoding for the CFI instructions.
+  virtual uint32_t
+      generateCompactUnwindEncoding(ArrayRef<MCCFIInstruction>) const {
+    return 0;
+  }
+};
+
+} // End llvm namespace
+
+#endif