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diff --git a/contrib/llvm/lib/CodeGen/AllocationOrder.h b/contrib/llvm/lib/CodeGen/AllocationOrder.h
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+++ b/contrib/llvm/lib/CodeGen/AllocationOrder.h
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+//===-- llvm/CodeGen/AllocationOrder.h - Allocation Order -*- C++ -*-------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements an allocation order for virtual registers.
+//
+// The preferred allocation order for a virtual register depends on allocation
+// hints and target hooks. The AllocationOrder class encapsulates all of that.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_ALLOCATIONORDER_H
+#define LLVM_CODEGEN_ALLOCATIONORDER_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/MC/MCRegisterInfo.h"
+
+namespace llvm {
+
+class RegisterClassInfo;
+class VirtRegMap;
+
+class AllocationOrder {
+  SmallVector<MCPhysReg, 16> Hints;
+  ArrayRef<MCPhysReg> Order;
+  int Pos;
+
+public:
+  /// Create a new AllocationOrder for VirtReg.
+  /// @param VirtReg      Virtual register to allocate for.
+  /// @param VRM          Virtual register map for function.
+  /// @param RegClassInfo Information about reserved and allocatable registers.
+  AllocationOrder(unsigned VirtReg,
+                  const VirtRegMap &VRM,
+                  const RegisterClassInfo &RegClassInfo);
+
+  /// Get the allocation order without reordered hints.
+  ArrayRef<MCPhysReg> getOrder() const { return Order; }
+
+  /// Return the next physical register in the allocation order, or 0.
+  /// It is safe to call next() again after it returned 0, it will keep
+  /// returning 0 until rewind() is called.
+  unsigned next() {
+    if (Pos < 0)
+      return Hints.end()[Pos++];
+    while (Pos < int(Order.size())) {
+      unsigned Reg = Order[Pos++];
+      if (!isHint(Reg))
+        return Reg;
+    }
+    return 0;
+  }
+
+  /// As next(), but allow duplicates to be returned, and stop before the
+  /// Limit'th register in the RegisterClassInfo allocation order.
+  ///
+  /// This can produce more than Limit registers if there are hints.
+  unsigned nextWithDups(unsigned Limit) {
+    if (Pos < 0)
+      return Hints.end()[Pos++];
+    if (Pos < int(Limit))
+      return Order[Pos++];
+    return 0;
+  }
+
+  /// Start over from the beginning.
+  void rewind() { Pos = -int(Hints.size()); }
+
+  /// Return true if the last register returned from next() was a preferred register.
+  bool isHint() const { return Pos <= 0; }
+
+  /// Return true if PhysReg is a preferred register.
+  bool isHint(unsigned PhysReg) const {
+    return std::find(Hints.begin(), Hints.end(), PhysReg) != Hints.end();
+  }
+};
+
+} // end namespace llvm
+
+#endif