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diff --git a/contrib/llvm/lib/CodeGen/ExactHazardRecognizer.h b/contrib/llvm/lib/CodeGen/ExactHazardRecognizer.h
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+//=- llvm/CodeGen/ExactHazardRecognizer.h - Scheduling Support -*- 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 the ExactHazardRecognizer class, which
+// implements hazard-avoidance heuristics for scheduling, based on the
+// scheduling itineraries specified for the target.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_EXACTHAZARDRECOGNIZER_H
+#define LLVM_CODEGEN_EXACTHAZARDRECOGNIZER_H
+
+#include "llvm/CodeGen/ScheduleHazardRecognizer.h"
+#include "llvm/CodeGen/ScheduleDAG.h"
+#include "llvm/Target/TargetInstrItineraries.h"
+
+namespace llvm {
+  class ExactHazardRecognizer : public ScheduleHazardRecognizer {
+    // ScoreBoard to track function unit usage. ScoreBoard[0] is a
+    // mask of the FUs in use in the cycle currently being
+    // schedule. ScoreBoard[1] is a mask for the next cycle. The
+    // ScoreBoard is used as a circular buffer with the current cycle
+    // indicated by Head.
+    class ScoreBoard {
+      unsigned *Data;
+
+      // The maximum number of cycles monitored by the Scoreboard. This
+      // value is determined based on the target itineraries to ensure
+      // that all hazards can be tracked.
+      size_t Depth;
+      // Indices into the Scoreboard that represent the current cycle.
+      size_t Head;
+    public:
+      ScoreBoard():Data(NULL), Depth(0), Head(0) { }
+      ~ScoreBoard() {
+        delete[] Data;
+      }
+
+      size_t getDepth() const { return Depth; }
+      unsigned& operator[](size_t idx) const {
+        assert(Depth && "ScoreBoard was not initialized properly!");
+
+        return Data[(Head + idx) % Depth];
+      }
+
+      void reset(size_t d = 1) {
+        if (Data == NULL) {
+          Depth = d;
+          Data = new unsigned[Depth];
+        }
+
+        memset(Data, 0, Depth * sizeof(Data[0]));
+        Head = 0;
+      }
+
+      void advance() {
+        Head = (Head + 1) % Depth;
+      }
+
+      // Print the scoreboard.
+      void dump() const;
+    };
+
+    // Itinerary data for the target.
+    const InstrItineraryData &ItinData;
+
+    ScoreBoard ReservedScoreboard;
+    ScoreBoard RequiredScoreboard;
+
+  public:
+    ExactHazardRecognizer(const InstrItineraryData &ItinData);
+
+    virtual HazardType getHazardType(SUnit *SU);
+    virtual void Reset();
+    virtual void EmitInstruction(SUnit *SU);
+    virtual void AdvanceCycle();
+  };
+}
+
+#endif