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// Copyright 2013 the V8 project authors. All rights reserved.
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#ifndef V8_HYDROGEN_CHECK_ELIMINATION_H_
#define V8_HYDROGEN_CHECK_ELIMINATION_H_

#include "hydrogen.h"
#include "hydrogen-alias-analysis.h"

namespace v8 {
namespace internal {


// Remove CheckMaps instructions through flow- and branch-sensitive analysis.
class HCheckEliminationPhase : public HPhase {
 public:
  explicit HCheckEliminationPhase(HGraph* graph)
      : HPhase("H_Check Elimination", graph), aliasing_() {
#ifdef DEBUG
    redundant_ = 0;
    removed_ = 0;
    removed_cho_ = 0;
    narrowed_ = 0;
    loads_ = 0;
    empty_ = 0;
    compares_true_ = 0;
    compares_false_ = 0;
    transitions_ = 0;
#endif
  }

  void Run();

  friend class HCheckTable;

 private:
  void PrintStats();

  HAliasAnalyzer* aliasing_;
#ifdef DEBUG
  int redundant_;
  int removed_;
  int removed_cho_;
  int narrowed_;
  int loads_;
  int empty_;
  int compares_true_;
  int compares_false_;
  int transitions_;
#endif
};


} }  // namespace v8::internal

#endif  // V8_HYDROGEN_CHECK_ELIMINATION_H_