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// Copyright 2013 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
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//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
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//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef V8_HYDROGEN_MARK_DEOPTIMIZE_H_
#define V8_HYDROGEN_MARK_DEOPTIMIZE_H_

#include "hydrogen.h"

namespace v8 {
namespace internal {


// Compute DeoptimizeOnUndefined flag for phis.  Any phi that can reach a use
// with DeoptimizeOnUndefined set must have DeoptimizeOnUndefined set.
// Currently only HCompareNumericAndBranch, with double input representation,
// has this flag set.  The flag is used by HChange tagged->double, which must
// deoptimize if one of its uses has this flag set.
class HMarkDeoptimizeOnUndefinedPhase : public HPhase {
 public:
  explicit HMarkDeoptimizeOnUndefinedPhase(HGraph* graph)
      : HPhase("H_Mark deoptimize on undefined", graph),
        worklist_(16, zone()) {}

  void Run();

 private:
  void ProcessPhi(HPhi* phi);

  // Preallocated worklist used as an optimization so we don't have
  // to allocate a new ZoneList for every ProcessPhi() invocation.
  ZoneList<HPhi*> worklist_;

  DISALLOW_COPY_AND_ASSIGN(HMarkDeoptimizeOnUndefinedPhase);
};


class HComputeChangeUndefinedToNaN : public HPhase {
 public:
  explicit HComputeChangeUndefinedToNaN(HGraph* graph)
      : HPhase("H_Compute change undefined to nan", graph) {}

  void Run();

 private:
  DISALLOW_COPY_AND_ASSIGN(HComputeChangeUndefinedToNaN);
};


} }  // namespace v8::internal

#endif  // V8_HYDROGEN_MARK_DEOPTIMIZE_H_