code.h.svn-base

Google浏览器V8内核代码

// Copyright 2006-2008 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:
//
//     * Redistributions of source code must retain the above copyright
//       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
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#ifndef V8_CODE_H_
#define V8_CODE_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) { }

  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_