| // 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 |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #ifndef V8_ARGUMENTS_H_ |
| #define V8_ARGUMENTS_H_ |
| |
| namespace v8 { |
| namespace internal { |
| |
| // Arguments provides access to runtime call parameters. |
| // |
| // It uses the fact that the instance fields of Arguments |
| // (length_, arguments_) are "overlayed" with the parameters |
| // (no. of parameters, and the parameter pointer) passed so |
| // that inside the C++ function, the parameters passed can |
| // be accessed conveniently: |
| // |
| // Object* Runtime_function(Arguments args) { |
| // ... use args[i] here ... |
| // } |
| |
| class Arguments BASE_EMBEDDED { |
| public: |
| Object*& operator[] (int index) { |
| ASSERT(0 <= index && index < length_); |
| return arguments_[-index]; |
| } |
| |
| template <class S> Handle<S> at(int index) { |
| Object** value = &((*this)[index]); |
| // This cast checks that the object we're accessing does indeed have the |
| // expected type. |
| S::cast(*value); |
| return Handle<S>(reinterpret_cast<S**>(value)); |
| } |
| |
| // Get the total number of arguments including the receiver. |
| int length() const { return length_; } |
| |
| private: |
| int length_; |
| Object** arguments_; |
| }; |
| |
| } } // namespace v8::internal |
| |
| #endif // V8_ARGUMENTS_H_ |