CSE2410 Fall 2014 Bounce

// Copyright 2012 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_

#include "allocation.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:

  Arguments(int length, Object** arguments)

      : length_(length), arguments_(arguments) { }

  Object*& operator[] (int index) {

    ASSERT(0 <= index && index < length_);

    return *(reinterpret_cast<Object**>(reinterpret_cast<intptr_t>(arguments_) -

                                        index * kPointerSize));

  }

  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));

  }

  int smi_at(int index) {

    return Smi::cast((*this)[index])->value();

  }

  double number_at(int index) {

    return (*this)[index]->Number();

  }

  // Get the total number of arguments including the receiver.

  int length() const { return length_; }

  Object** arguments() { return arguments_; }

 private:

  int length_;

  Object** arguments_;

};

// For each type of callback, we have a list of arguments

// They are used to generate the Call() functions below

// These aren't included in the list as they have duplicate signatures

// F(NamedPropertyEnumeratorCallback, ...)

// F(NamedPropertyGetterCallback, ...)

#define FOR_EACH_CALLBACK_TABLE_MAPPING_0(F) \

  F(IndexedPropertyEnumeratorCallback, v8::Array) \

#define FOR_EACH_CALLBACK_TABLE_MAPPING_1(F) \

  F(AccessorGetterCallback, v8::Value, v8::Local<v8::String>) \

  F(NamedPropertyQueryCallback, \

    v8::Integer, \

    v8::Local<v8::String>) \

  F(NamedPropertyDeleterCallback, \

    v8::Boolean, \

    v8::Local<v8::String>) \

  F(IndexedPropertyGetterCallback, \

    v8::Value, \

    uint32_t) \

  F(IndexedPropertyQueryCallback, \

    v8::Integer, \

    uint32_t) \

  F(IndexedPropertyDeleterCallback, \

    v8::Boolean, \

    uint32_t) \

#define FOR_EACH_CALLBACK_TABLE_MAPPING_2(F) \

  F(NamedPropertySetterCallback, \

    v8::Value, \

    v8::Local<v8::String>, \

    v8::Local<v8::Value>) \

  F(IndexedPropertySetterCallback, \

    v8::Value, \

    uint32_t, \

    v8::Local<v8::Value>) \

#define FOR_EACH_CALLBACK_TABLE_MAPPING_2_VOID_RETURN(F) \

  F(AccessorSetterCallback, \

    void, \

    v8::Local<v8::String>, \

    v8::Local<v8::Value>) \

// Custom arguments replicate a small segment of stack that can be

// accessed through an Arguments object the same way the actual stack

// can.

template<int kArrayLength>

class CustomArgumentsBase : public Relocatable {

 public:

  virtual inline void IterateInstance(ObjectVisitor* v) {

    v->VisitPointers(values_, values_ + kArrayLength);

  }

 protected:

  inline Object** begin() { return values_; }

  explicit inline CustomArgumentsBase(Isolate* isolate)

      : Relocatable(isolate) {}

  Object* values_[kArrayLength];

};

template<typename T>

class CustomArguments : public CustomArgumentsBase<T::kArgsLength> {

 public:

  static const int kReturnValueOffset = T::kReturnValueIndex;

  typedef CustomArgumentsBase<T::kArgsLength> Super;

  ~CustomArguments() {

    this->begin()[kReturnValueOffset] =

        reinterpret_cast<Object*>(kHandleZapValue);

  }

 protected:

  explicit inline CustomArguments(Isolate* isolate) : Super(isolate) {}

  template<typename V>

  v8::Handle<V> GetReturnValue(Isolate* isolate);

  inline Isolate* isolate() {

    return reinterpret_cast<Isolate*>(this->begin()[T::kIsolateIndex]);

  }

};

class PropertyCallbackArguments

    : public CustomArguments<PropertyCallbackInfo<Value> > {

 public:

  typedef PropertyCallbackInfo<Value> T;

  typedef CustomArguments<T> Super;

  static const int kArgsLength = T::kArgsLength;

  static const int kThisIndex = T::kThisIndex;

  static const int kHolderIndex = T::kHolderIndex;

  static const int kDataIndex = T::kDataIndex;

  static const int kReturnValueDefaultValueIndex =

      T::kReturnValueDefaultValueIndex;

  static const int kIsolateIndex = T::kIsolateIndex;

  PropertyCallbackArguments(Isolate* isolate,

                            Object* data,

                            Object* self,

                            JSObject* holder)

      : Super(isolate) {

    Object** values = this->begin();

    values[T::kThisIndex] = self;

    values[T::kHolderIndex] = holder;

    values[T::kDataIndex] = data;

    values[T::kIsolateIndex] = reinterpret_cast<Object*>(isolate);

    // Here the hole is set as default value.

    // It cannot escape into js as it's remove in Call below.

    values[T::kReturnValueDefaultValueIndex] =

        isolate->heap()->the_hole_value();

    values[T::kReturnValueIndex] = isolate->heap()->the_hole_value();

    ASSERT(values[T::kHolderIndex]->IsHeapObject());

    ASSERT(values[T::kIsolateIndex]->IsSmi());

  }

  /*

   * The following Call functions wrap the calling of all callbacks to handle

   * calling either the old or the new style callbacks depending on which one

   * has been registered.

   * For old callbacks which return an empty handle, the ReturnValue is checked

   * and used if it's been set to anything inside the callback.

   * New style callbacks always use the return value.

   */

#define WRITE_CALL_0(Function, ReturnValue)                                  \

  v8::Handle<ReturnValue> Call(Function f);                                  \

#define WRITE_CALL_1(Function, ReturnValue, Arg1)                            \

  v8::Handle<ReturnValue> Call(Function f, Arg1 arg1);                       \

#define WRITE_CALL_2(Function, ReturnValue, Arg1, Arg2)                      \

  v8::Handle<ReturnValue> Call(Function f, Arg1 arg1, Arg2 arg2);            \

#define WRITE_CALL_2_VOID(Function, ReturnValue, Arg1, Arg2)                 \

  void Call(Function f, Arg1 arg1, Arg2 arg2);                               \

FOR_EACH_CALLBACK_TABLE_MAPPING_0(WRITE_CALL_0)

FOR_EACH_CALLBACK_TABLE_MAPPING_1(WRITE_CALL_1)

FOR_EACH_CALLBACK_TABLE_MAPPING_2(WRITE_CALL_2)

FOR_EACH_CALLBACK_TABLE_MAPPING_2_VOID_RETURN(WRITE_CALL_2_VOID)

#undef WRITE_CALL_0

#undef WRITE_CALL_1

#undef WRITE_CALL_2

#undef WRITE_CALL_2_VOID

};

class FunctionCallbackArguments

    : public CustomArguments<FunctionCallbackInfo<Value> > {

 public:

  typedef FunctionCallbackInfo<Value> T;

  typedef CustomArguments<T> Super;

  static const int kArgsLength = T::kArgsLength;

  static const int kHolderIndex = T::kHolderIndex;

  static const int kDataIndex = T::kDataIndex;

  static const int kReturnValueDefaultValueIndex =

      T::kReturnValueDefaultValueIndex;

  static const int kIsolateIndex = T::kIsolateIndex;

  static const int kCalleeIndex = T::kCalleeIndex;

  static const int kContextSaveIndex = T::kContextSaveIndex;

  FunctionCallbackArguments(internal::Isolate* isolate,

      internal::Object* data,

      internal::JSFunction* callee,

      internal::Object* holder,

      internal::Object** argv,

      int argc,

      bool is_construct_call)

        : Super(isolate),

          argv_(argv),

          argc_(argc),

          is_construct_call_(is_construct_call) {

    Object** values = begin();

    values[T::kDataIndex] = data;

    values[T::kCalleeIndex] = callee;

    values[T::kHolderIndex] = holder;

    values[T::kContextSaveIndex] = isolate->heap()->the_hole_value();

    values[T::kIsolateIndex] = reinterpret_cast<internal::Object*>(isolate);

    // Here the hole is set as default value.

    // It cannot escape into js as it's remove in Call below.

    values[T::kReturnValueDefaultValueIndex] =

        isolate->heap()->the_hole_value();

    values[T::kReturnValueIndex] = isolate->heap()->the_hole_value();

    ASSERT(values[T::kCalleeIndex]->IsJSFunction());

    ASSERT(values[T::kHolderIndex]->IsHeapObject());

    ASSERT(values[T::kIsolateIndex]->IsSmi());

  }

  /*

   * The following Call function wraps the calling of all callbacks to handle

   * calling either the old or the new style callbacks depending on which one

   * has been registered.

   * For old callbacks which return an empty handle, the ReturnValue is checked

   * and used if it's been set to anything inside the callback.

   * New style callbacks always use the return value.

   */

  v8::Handle<v8::Value> Call(FunctionCallback f);

 private:

  internal::Object** argv_;

  int argc_;

  bool is_construct_call_;

};

#define DECLARE_RUNTIME_FUNCTION(Type, Name)    \

Type Name(int args_length, Object** args_object, Isolate* isolate)

#define RUNTIME_FUNCTION(Type, Name)                                  \

static Type __RT_impl_##Name(Arguments args, Isolate* isolate);       \

Type Name(int args_length, Object** args_object, Isolate* isolate) {  \

  Arguments args(args_length, args_object);                           \

  return __RT_impl_##Name(args, isolate);                             \

}                                                                     \

static Type __RT_impl_##Name(Arguments args, Isolate* isolate)

#define RUNTIME_ARGUMENTS(isolate, args) \

  args.length(), args.arguments(), isolate

} }  // namespace v8::internal

#endif  // V8_ARGUMENTS_H_