src/code.h

// Copyright 2006-2008 the V8 project authors. All rights reserved.
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// 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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//       with the distribution.
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//
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#ifndef V8_CODE_H_
#define V8_CODE_H_

#include "allocation.h"
#include "handles.h"
#include "objects.h"

namespace v8 {
namespace internal {


// Wrapper class for passing expected and actual parameter counts as
// either registers or immediate values. Used to make sure that the
// caller provides exactly the expected number of parameters to the
// callee.
class ParameterCount BASE_EMBEDDED {
 public:
  explicit ParameterCount(Register reg)
      : reg_(reg), immediate_(0) { }
  explicit ParameterCount(int immediate)
      : reg_(no_reg), immediate_(immediate) { }
  explicit ParameterCount(Handle<JSFunction> f)
      : reg_(no_reg), immediate_(f->shared()->formal_parameter_count()) { }

  bool is_reg() const { return !reg_.is(no_reg); }
  bool is_immediate() const { return !is_reg(); }

  Register reg() const {
    ASSERT(is_reg());
    return reg_;
  }
  int immediate() const {
    ASSERT(is_immediate());
    return immediate_;
  }

 private:
  const Register reg_;
  const int immediate_;

  DISALLOW_IMPLICIT_CONSTRUCTORS(ParameterCount);
};


} }  // namespace v8::internal

#endif  // V8_CODE_H_