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diff --git a/contrib/llvm/lib/CodeGen/SimpleHazardRecognizer.h b/contrib/llvm/lib/CodeGen/SimpleHazardRecognizer.h
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+++ b/contrib/llvm/lib/CodeGen/SimpleHazardRecognizer.h
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+//=- llvm/CodeGen/SimpleHazardRecognizer.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 SimpleHazardRecognizer class, which
+// implements hazard-avoidance heuristics for scheduling, based on the
+// scheduling itineraries specified for the target.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_SIMPLEHAZARDRECOGNIZER_H
+#define LLVM_CODEGEN_SIMPLEHAZARDRECOGNIZER_H
+
+#include "llvm/CodeGen/ScheduleHazardRecognizer.h"
+#include "llvm/CodeGen/ScheduleDAG.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetInstrInfo.h"
+
+namespace llvm {
+  /// SimpleHazardRecognizer - A *very* simple hazard recognizer. It uses
+  /// a coarse classification and attempts to avoid that instructions of
+  /// a given class aren't grouped too densely together.
+  class SimpleHazardRecognizer : public ScheduleHazardRecognizer {
+    /// Class - A simple classification for SUnits.
+    enum Class {
+      Other, Load, Store
+    };
+
+    /// Window - The Class values of the most recently issued
+    /// instructions.
+    Class Window[8];
+
+    /// getClass - Classify the given SUnit.
+    Class getClass(const SUnit *SU) {
+      const MachineInstr *MI = SU->getInstr();
+      const TargetInstrDesc &TID = MI->getDesc();
+      if (TID.mayLoad())
+        return Load;
+      if (TID.mayStore())
+        return Store;
+      return Other;
+    }
+
+    /// Step - Rotate the existing entries in Window and insert the
+    /// given class value in position as the most recent.
+    void Step(Class C) {
+      std::copy(Window+1, array_endof(Window), Window);
+      Window[array_lengthof(Window)-1] = C;
+    }
+
+  public:
+    SimpleHazardRecognizer() : Window() {
+      Reset();
+    }
+
+    virtual HazardType getHazardType(SUnit *SU) {
+      Class C = getClass(SU);
+      if (C == Other)
+        return NoHazard;
+      unsigned Score = 0;
+      for (unsigned i = 0; i != array_lengthof(Window); ++i)
+        if (Window[i] == C)
+          Score += i + 1;
+      if (Score > array_lengthof(Window) * 2)
+        return Hazard;
+      return NoHazard;
+    }
+
+    virtual void Reset() {
+      for (unsigned i = 0; i != array_lengthof(Window); ++i)
+        Window[i] = Other;
+    }
+
+    virtual void EmitInstruction(SUnit *SU) {
+      Step(getClass(SU));
+    }
+
+    virtual void AdvanceCycle() {
+      Step(Other);
+    }
+  };
+}
+
+#endif