/deps/v8/src/runtime.cc

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// 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.

#include <stdlib.h>
#include <limits>

#include "v8.h"

#include "accessors.h"
#include "api.h"
#include "arguments.h"
#include "bootstrapper.h"
#include "codegen.h"
#include "compilation-cache.h"
#include "compiler.h"
#include "cpu.h"
#include "cpu-profiler.h"
#include "dateparser-inl.h"
#include "debug.h"
#include "deoptimizer.h"
#include "date.h"
#include "execution.h"
#include "full-codegen.h"
#include "global-handles.h"
#include "isolate-inl.h"
#include "jsregexp.h"
#include "jsregexp-inl.h"
#include "json-parser.h"
#include "json-stringifier.h"
#include "liveedit.h"
#include "misc-intrinsics.h"
#include "parser.h"
#include "platform.h"
#include "runtime-profiler.h"
#include "runtime.h"
#include "scopeinfo.h"
#include "smart-pointers.h"
#include "string-search.h"
#include "stub-cache.h"
#include "uri.h"
#include "v8conversions.h"
#include "v8threads.h"
#include "vm-state-inl.h"

#ifdef V8_I18N_SUPPORT
#include "i18n.h"
#include "unicode/brkiter.h"
#include "unicode/calendar.h"
#include "unicode/coll.h"
#include "unicode/curramt.h"
#include "unicode/datefmt.h"
#include "unicode/dcfmtsym.h"
#include "unicode/decimfmt.h"
#include "unicode/dtfmtsym.h"
#include "unicode/dtptngen.h"
#include "unicode/locid.h"
#include "unicode/numfmt.h"
#include "unicode/numsys.h"
#include "unicode/smpdtfmt.h"
#include "unicode/timezone.h"
#include "unicode/uchar.h"
#include "unicode/ucol.h"
#include "unicode/ucurr.h"
#include "unicode/uloc.h"
#include "unicode/unum.h"
#include "unicode/uversion.h"
#endif

#ifndef _STLP_VENDOR_CSTD
// STLPort doesn't import fpclassify and isless into the std namespace.
using std::fpclassify;
using std::isless;
#endif

namespace v8 {
namespace internal {


#define RUNTIME_ASSERT(value) \
  if (!(value)) return isolate->ThrowIllegalOperation();

// Cast the given object to a value of the specified type and store
// it in a variable with the given name.  If the object is not of the
// expected type call IllegalOperation and return.
#define CONVERT_ARG_CHECKED(Type, name, index)                       \
  RUNTIME_ASSERT(args[index]->Is##Type());                           \
  Type* name = Type::cast(args[index]);

#define CONVERT_ARG_HANDLE_CHECKED(Type, name, index)                \
  RUNTIME_ASSERT(args[index]->Is##Type());                           \
  Handle<Type> name = args.at<Type>(index);

// Cast the given object to a boolean and store it in a variable with
// the given name.  If the object is not a boolean call IllegalOperation
// and return.
#define CONVERT_BOOLEAN_ARG_CHECKED(name, index)                     \
  RUNTIME_ASSERT(args[index]->IsBoolean());                          \
  bool name = args[index]->IsTrue();

// Cast the given argument to a Smi and store its value in an int variable
// with the given name.  If the argument is not a Smi call IllegalOperation
// and return.
#define CONVERT_SMI_ARG_CHECKED(name, index)                         \
  RUNTIME_ASSERT(args[index]->IsSmi());                              \
  int name = args.smi_at(index);

// Cast the given argument to a double and store it in a variable with
// the given name.  If the argument is not a number (as opposed to
// the number not-a-number) call IllegalOperation and return.
#define CONVERT_DOUBLE_ARG_CHECKED(name, index)                      \
  RUNTIME_ASSERT(args[index]->IsNumber());                           \
  double name = args.number_at(index);

// Call the specified converter on the object *comand store the result in
// a variable of the specified type with the given name.  If the
// object is not a Number call IllegalOperation and return.
#define CONVERT_NUMBER_CHECKED(type, name, Type, obj)                \
  RUNTIME_ASSERT(obj->IsNumber());                                   \
  type name = NumberTo##Type(obj);


// Cast the given argument to PropertyDetails and store its value in a
// variable with the given name.  If the argument is not a Smi call
// IllegalOperation and return.
#define CONVERT_PROPERTY_DETAILS_CHECKED(name, index)                \
  RUNTIME_ASSERT(args[index]->IsSmi());                              \
  PropertyDetails name = PropertyDetails(Smi::cast(args[index]));


// Assert that the given argument has a valid value for a StrictModeFlag
// and store it in a StrictModeFlag variable with the given name.
#define CONVERT_STRICT_MODE_ARG_CHECKED(name, index)                 \
  RUNTIME_ASSERT(args[index]->IsSmi());                              \
  RUNTIME_ASSERT(args.smi_at(index) == kStrictMode ||                \
                 args.smi_at(index) == kNonStrictMode);              \
  StrictModeFlag name =                                              \
      static_cast<StrictModeFlag>(args.smi_at(index));


// Assert that the given argument has a valid value for a LanguageMode
// and store it in a LanguageMode variable with the given name.
#define CONVERT_LANGUAGE_MODE_ARG(name, index)                       \
  ASSERT(args[index]->IsSmi());                                      \
  ASSERT(args.smi_at(index) == CLASSIC_MODE ||                       \
         args.smi_at(index) == STRICT_MODE ||                        \
         args.smi_at(index) == EXTENDED_MODE);                       \
  LanguageMode name =                                                \
      static_cast<LanguageMode>(args.smi_at(index));


static Handle<Map> ComputeObjectLiteralMap(
    Handle<Context> context,
    Handle<FixedArray> constant_properties,
    bool* is_result_from_cache) {
  Isolate* isolate = context->GetIsolate();
  int properties_length = constant_properties->length();
  int number_of_properties = properties_length / 2;
  // Check that there are only internal strings and array indices among keys.
  int number_of_string_keys = 0;
  for (int p = 0; p != properties_length; p += 2) {
    Object* key = constant_properties->get(p);
    uint32_t element_index = 0;
    if (key->IsInternalizedString()) {
      number_of_string_keys++;
    } else if (key->ToArrayIndex(&element_index)) {
      // An index key does not require space in the property backing store.
      number_of_properties--;
    } else {
      // Bail out as a non-internalized-string non-index key makes caching
      // impossible.
      // ASSERT to make sure that the if condition after the loop is false.
      ASSERT(number_of_string_keys != number_of_properties);
      break;
    }
  }
  // If we only have internalized strings and array indices among keys then we
  // can use the map cache in the native context.
  const int kMaxKeys = 10;
  if ((number_of_string_keys == number_of_properties) &&
      (number_of_string_keys < kMaxKeys)) {
    // Create the fixed array with the key.
    Handle<FixedArray> keys =
        isolate->factory()->NewFixedArray(number_of_string_keys);
    if (number_of_string_keys > 0) {
      int index = 0;
      for (int p = 0; p < properties_length; p += 2) {
        Object* key = constant_properties->get(p);
        if (key->IsInternalizedString()) {
          keys->set(index++, key);
        }
      }
      ASSERT(index == number_of_string_keys);
    }
    *is_result_from_cache = true;
    return isolate->factory()->ObjectLiteralMapFromCache(context, keys);
  }
  *is_result_from_cache = false;
  return isolate->factory()->CopyMap(
      Handle<Map>(context->object_function()->initial_map()),
      number_of_properties);
}


static Handle<Object> CreateLiteralBoilerplate(
    Isolate* isolate,
    Handle<FixedArray> literals,
    Handle<FixedArray> constant_properties);


static Handle<Object> CreateObjectLiteralBoilerplate(
    Isolate* isolate,
    Handle<FixedArray> literals,
    Handle<FixedArray> constant_properties,
    bool should_have_fast_elements,
    bool has_function_literal) {
  // Get the native context from the literals array.  This is the
  // context in which the function was created and we use the object
  // function from this context to create the object literal.  We do
  // not use the object function from the current native context
  // because this might be the object function from another context
  // which we should not have access to.
  Handle<Context> context =
      Handle<Context>(JSFunction::NativeContextFromLiterals(*literals));

  // In case we have function literals, we want the object to be in
  // slow properties mode for now. We don't go in the map cache because
  // maps with constant functions can't be shared if the functions are
  // not the same (which is the common case).
  bool is_result_from_cache = false;
  Handle<Map> map = has_function_literal
      ? Handle<Map>(context->object_function()->initial_map())
      : ComputeObjectLiteralMap(context,
                                constant_properties,
                                &is_result_from_cache);

  Handle<JSObject> boilerplate =
      isolate->factory()->NewJSObjectFromMap(
          map, isolate->heap()->GetPretenureMode());

  // Normalize the elements of the boilerplate to save space if needed.
  if (!should_have_fast_elements) JSObject::NormalizeElements(boilerplate);

  // Add the constant properties to the boilerplate.
  int length = constant_properties->length();
  bool should_transform =
      !is_result_from_cache && boilerplate->HasFastProperties();
  if (should_transform || has_function_literal) {
    // Normalize the properties of object to avoid n^2 behavior
    // when extending the object multiple properties. Indicate the number of
    // properties to be added.
    JSObject::NormalizeProperties(
        boilerplate, KEEP_INOBJECT_PROPERTIES, length / 2);
  }

  // TODO(verwaest): Support tracking representations in the boilerplate.
  for (int index = 0; index < length; index +=2) {
    Handle<Object> key(constant_properties->get(index+0), isolate);
    Handle<Object> value(constant_properties->get(index+1), isolate);
    if (value->IsFixedArray()) {
      // The value contains the constant_properties of a
      // simple object or array literal.
      Handle<FixedArray> array = Handle<FixedArray>::cast(value);
      value = CreateLiteralBoilerplate(isolate, literals, array);
      if (value.is_null()) return value;
    }
    Handle<Object> result;
    uint32_t element_index = 0;
    JSReceiver::StoreMode mode = value->IsJSObject()
        ? JSReceiver::FORCE_FIELD
        : JSReceiver::ALLOW_AS_CONSTANT;
    if (key->IsInternalizedString()) {
      if (Handle<String>::cast(key)->AsArrayIndex(&element_index)) {
        // Array index as string (uint32).
        result = JSObject::SetOwnElement(
            boilerplate, element_index, value, kNonStrictMode);
      } else {
        Handle<String> name(String::cast(*key));
        ASSERT(!name->AsArrayIndex(&element_index));
        result = JSObject::SetLocalPropertyIgnoreAttributes(
            boilerplate, name, value, NONE,
            Object::OPTIMAL_REPRESENTATION, mode);
      }
    } else if (key->ToArrayIndex(&element_index)) {
      // Array index (uint32).
      result = JSObject::SetOwnElement(
          boilerplate, element_index, value, kNonStrictMode);
    } else {
      // Non-uint32 number.
      ASSERT(key->IsNumber());
      double num = key->Number();
      char arr[100];
      Vector<char> buffer(arr, ARRAY_SIZE(arr));
      const char* str = DoubleToCString(num, buffer);
      Handle<String> name =
          isolate->factory()->NewStringFromAscii(CStrVector(str));
      result = JSObject::SetLocalPropertyIgnoreAttributes(
          boilerplate, name, value, NONE,
          Object::OPTIMAL_REPRESENTATION, mode);
    }
    // If setting the property on the boilerplate throws an
    // exception, the exception is converted to an empty handle in
    // the handle based operations.  In that case, we need to
    // convert back to an exception.
    if (result.is_null()) return result;
  }

  // Transform to fast properties if necessary. For object literals with
  // containing function literals we defer this operation until after all
  // computed properties have been assigned so that we can generate
  // constant function properties.
  if (should_transform && !has_function_literal) {
    JSObject::TransformToFastProperties(
        boilerplate, boilerplate->map()->unused_property_fields());
  }

  return boilerplate;
}


MaybeObject* TransitionElements(Handle<Object> object,
                                ElementsKind to_kind,
                                Isolate* isolate) {
  HandleScope scope(isolate);
  if (!object->IsJSObject()) return isolate->ThrowIllegalOperation();
  ElementsKind from_kind =
      Handle<JSObject>::cast(object)->map()->elements_kind();
  if (Map::IsValidElementsTransition(from_kind, to_kind)) {
    Handle<Object> result = JSObject::TransitionElementsKind(
        Handle<JSObject>::cast(object), to_kind);
    if (result.is_null()) return isolate->ThrowIllegalOperation();
    return *result;
  }
  return isolate->ThrowIllegalOperation();
}


static const int kSmiLiteralMinimumLength = 1024;


Handle<Object> Runtime::CreateArrayLiteralBoilerplate(
    Isolate* isolate,
    Handle<FixedArray> literals,
    Handle<FixedArray> elements) {
  // Create the JSArray.
  Handle<JSFunction> constructor(
      JSFunction::NativeContextFromLiterals(*literals)->array_function());

  Handle<JSArray> object = Handle<JSArray>::cast(
      isolate->factory()->NewJSObject(
          constructor, isolate->heap()->GetPretenureMode()));

  ElementsKind constant_elements_kind =
      static_cast<ElementsKind>(Smi::cast(elements->get(0))->value());
  Handle<FixedArrayBase> constant_elements_values(
      FixedArrayBase::cast(elements->get(1)));

  ASSERT(IsFastElementsKind(constant_elements_kind));
  Context* native_context = isolate->context()->native_context();
  Object* maybe_maps_array = native_context->js_array_maps();
  ASSERT(!maybe_maps_array->IsUndefined());
  Object* maybe_map = FixedArray::cast(maybe_maps_array)->get(
      constant_elements_kind);
  ASSERT(maybe_map->IsMap());
  object->set_map(Map::cast(maybe_map));

  Handle<FixedArrayBase> copied_elements_values;
  if (IsFastDoubleElementsKind(constant_elements_kind)) {
    ASSERT(FLAG_smi_only_arrays);
    copied_elements_values = isolate->factory()->CopyFixedDoubleArray(
        Handle<FixedDoubleArray>::cast(constant_elements_values));
  } else {
    ASSERT(IsFastSmiOrObjectElementsKind(constant_elements_kind));
    const bool is_cow =
        (constant_elements_values->map() ==
         isolate->heap()->fixed_cow_array_map());
    if (is_cow) {
      copied_elements_values = constant_elements_values;
#if DEBUG
      Handle<FixedArray> fixed_array_values =
          Handle<FixedArray>::cast(copied_elements_values);
      for (int i = 0; i < fixed_array_values->length(); i++) {
        ASSERT(!fixed_array_values->get(i)->IsFixedArray());
      }
#endif
    } else {
      Handle<FixedArray> fixed_array_values =
          Handle<FixedArray>::cast(constant_elements_values);
      Handle<FixedArray> fixed_array_values_copy =
          isolate->factory()->CopyFixedArray(fixed_array_values);
      copied_elements_values = fixed_array_values_copy;
      for (int i = 0; i < fixed_array_values->length(); i++) {
        Object* current = fixed_array_values->get(i);
        if (current->IsFixedArray()) {
          // The value contains the constant_properties of a
          // simple object or array literal.
          Handle<FixedArray> fa(FixedArray::cast(fixed_array_values->get(i)));
          Handle<Object> result =
              CreateLiteralBoilerplate(isolate, literals, fa);
          if (result.is_null()) return result;
          fixed_array_values_copy->set(i, *result);
        }
      }
    }
  }
  object->set_elements(*copied_elements_values);
  object->set_length(Smi::FromInt(copied_elements_values->length()));

  //  Ensure that the boilerplate object has FAST_*_ELEMENTS, unless the flag is
  //  on or the object is larger than the threshold.
  if (!FLAG_smi_only_arrays &&
      constant_elements_values->length() < kSmiLiteralMinimumLength) {
    ElementsKind elements_kind = object->GetElementsKind();
    if (!IsFastObjectElementsKind(elements_kind)) {
      if (IsFastHoleyElementsKind(elements_kind)) {
        CHECK(!TransitionElements(object, FAST_HOLEY_ELEMENTS,
                                  isolate)->IsFailure());
      } else {
        CHECK(!TransitionElements(object, FAST_ELEMENTS, isolate)->IsFailure());
      }
    }
  }

  object->ValidateElements();
  return object;
}


static Handle<Object> CreateLiteralBoilerplate(
    Isolate* isolate,
    Handle<FixedArray> literals,
    Handle<FixedArray> array) {
  Handle<FixedArray> elements = CompileTimeValue::GetElements(array);
  const bool kHasNoFunctionLiteral = false;
  switch (CompileTimeValue::GetLiteralType(array)) {
    case CompileTimeValue::OBJECT_LITERAL_FAST_ELEMENTS:
      return CreateObjectLiteralBoilerplate(isolate,
                                            literals,
                                            elements,
                                            true,
                                            kHasNoFunctionLiteral);
    case CompileTimeValue::OBJECT_LITERAL_SLOW_ELEMENTS:
      return CreateObjectLiteralBoilerplate(isolate,
                                            literals,
                                            elements,
                                            false,
                                            kHasNoFunctionLiteral);
    case CompileTimeValue::ARRAY_LITERAL:
      return Runtime::CreateArrayLiteralBoilerplate(
          isolate, literals, elements);
    default:
      UNREACHABLE();
      return Handle<Object>::null();
  }
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_CreateObjectLiteral) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 4);
  CONVERT_ARG_HANDLE_CHECKED(FixedArray, literals, 0);
  CONVERT_SMI_ARG_CHECKED(literals_index, 1);
  CONVERT_ARG_HANDLE_CHECKED(FixedArray, constant_properties, 2);
  CONVERT_SMI_ARG_CHECKED(flags, 3);
  bool should_have_fast_elements = (flags & ObjectLiteral::kFastElements) != 0;
  bool has_function_literal = (flags & ObjectLiteral::kHasFunction) != 0;

  // Check if boilerplate exists. If not, create it first.
  Handle<Object> boilerplate(literals->get(literals_index), isolate);
  if (*boilerplate == isolate->heap()->undefined_value()) {
    boilerplate = CreateObjectLiteralBoilerplate(isolate,
                                                 literals,
                                                 constant_properties,
                                                 should_have_fast_elements,
                                                 has_function_literal);
    RETURN_IF_EMPTY_HANDLE(isolate, boilerplate);
    // Update the functions literal and return the boilerplate.
    literals->set(literals_index, *boilerplate);
  }
  return JSObject::cast(*boilerplate)->DeepCopy(isolate);
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_CreateObjectLiteralShallow) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 4);
  CONVERT_ARG_HANDLE_CHECKED(FixedArray, literals, 0);
  CONVERT_SMI_ARG_CHECKED(literals_index, 1);
  CONVERT_ARG_HANDLE_CHECKED(FixedArray, constant_properties, 2);
  CONVERT_SMI_ARG_CHECKED(flags, 3);
  bool should_have_fast_elements = (flags & ObjectLiteral::kFastElements) != 0;
  bool has_function_literal = (flags & ObjectLiteral::kHasFunction) != 0;

  // Check if boilerplate exists. If not, create it first.
  Handle<Object> boilerplate(literals->get(literals_index), isolate);
  if (*boilerplate == isolate->heap()->undefined_value()) {
    boilerplate = CreateObjectLiteralBoilerplate(isolate,
                                                 literals,
                                                 constant_properties,
                                                 should_have_fast_elements,
                                                 has_function_literal);
    RETURN_IF_EMPTY_HANDLE(isolate, boilerplate);
    // Update the functions literal and return the boilerplate.
    literals->set(literals_index, *boilerplate);
  }
  return isolate->heap()->CopyJSObject(JSObject::cast(*boilerplate));
}


static Handle<AllocationSite> GetLiteralAllocationSite(
    Isolate* isolate,
    Handle<FixedArray> literals,
    int literals_index,
    Handle<FixedArray> elements) {
  // Check if boilerplate exists. If not, create it first.
  Handle<Object> literal_site(literals->get(literals_index), isolate);
  Handle<AllocationSite> site;
  if (*literal_site == isolate->heap()->undefined_value()) {
    ASSERT(*elements != isolate->heap()->empty_fixed_array());
    Handle<Object> boilerplate =
        Runtime::CreateArrayLiteralBoilerplate(isolate, literals, elements);
    if (boilerplate.is_null()) return site;
    site = isolate->factory()->NewAllocationSite();
    site->set_transition_info(*boilerplate);
    literals->set(literals_index, *site);
  } else {
    site = Handle<AllocationSite>::cast(literal_site);
  }

  return site;
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_CreateArrayLiteral) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 3);
  CONVERT_ARG_HANDLE_CHECKED(FixedArray, literals, 0);
  CONVERT_SMI_ARG_CHECKED(literals_index, 1);
  CONVERT_ARG_HANDLE_CHECKED(FixedArray, elements, 2);

  Handle<AllocationSite> site = GetLiteralAllocationSite(isolate, literals,
      literals_index, elements);
  RETURN_IF_EMPTY_HANDLE(isolate, site);

  JSObject* boilerplate = JSObject::cast(site->transition_info());
  return boilerplate->DeepCopy(isolate);
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_CreateArrayLiteralShallow) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 3);
  CONVERT_ARG_HANDLE_CHECKED(FixedArray, literals, 0);
  CONVERT_SMI_ARG_CHECKED(literals_index, 1);
  CONVERT_ARG_HANDLE_CHECKED(FixedArray, elements, 2);

  Handle<AllocationSite> site = GetLiteralAllocationSite(isolate, literals,
      literals_index, elements);
  RETURN_IF_EMPTY_HANDLE(isolate, site);

  JSObject* boilerplate = JSObject::cast(site->transition_info());
  if (boilerplate->elements()->map() ==
      isolate->heap()->fixed_cow_array_map()) {
    isolate->counters()->cow_arrays_created_runtime()->Increment();
  }

  AllocationSiteMode mode = AllocationSite::GetMode(
      boilerplate->GetElementsKind());
  if (mode == TRACK_ALLOCATION_SITE) {
    return isolate->heap()->CopyJSObjectWithAllocationSite(
        boilerplate, *site);
  }

  return isolate->heap()->CopyJSObject(boilerplate);
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_CreateSymbol) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 1);
  Handle<Object> name(args[0], isolate);
  RUNTIME_ASSERT(name->IsString() || name->IsUndefined());
  Symbol* symbol;
  MaybeObject* maybe = isolate->heap()->AllocateSymbol();
  if (!maybe->To(&symbol)) return maybe;
  if (name->IsString()) symbol->set_name(*name);
  return symbol;
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_SymbolName) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 1);
  CONVERT_ARG_CHECKED(Symbol, symbol, 0);
  return symbol->name();
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_CreateJSProxy) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 2);
  CONVERT_ARG_CHECKED(JSReceiver, handler, 0);
  Object* prototype = args[1];
  Object* used_prototype =
      prototype->IsJSReceiver() ? prototype : isolate->heap()->null_value();
  return isolate->heap()->AllocateJSProxy(handler, used_prototype);
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_CreateJSFunctionProxy) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 4);
  CONVERT_ARG_CHECKED(JSReceiver, handler, 0);
  Object* call_trap = args[1];
  RUNTIME_ASSERT(call_trap->IsJSFunction() || call_trap->IsJSFunctionProxy());
  CONVERT_ARG_CHECKED(JSFunction, construct_trap, 2);
  Object* prototype = args[3];
  Object* used_prototype =
      prototype->IsJSReceiver() ? prototype : isolate->heap()->null_value();
  return isolate->heap()->AllocateJSFunctionProxy(
      handler, call_trap, construct_trap, used_prototype);
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_IsJSProxy) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 1);
  Object* obj = args[0];
  return isolate->heap()->ToBoolean(obj->IsJSProxy());
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_IsJSFunctionProxy) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 1);
  Object* obj = args[0];
  return isolate->heap()->ToBoolean(obj->IsJSFunctionProxy());
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_GetHandler) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 1);
  CONVERT_ARG_CHECKED(JSProxy, proxy, 0);
  return proxy->handler();
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_GetCallTrap) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 1);
  CONVERT_ARG_CHECKED(JSFunctionProxy, proxy, 0);
  return proxy->call_trap();
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_GetConstructTrap) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 1);
  CONVERT_ARG_CHECKED(JSFunctionProxy, proxy, 0);
  return proxy->construct_trap();
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_Fix) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 1);
  CONVERT_ARG_CHECKED(JSProxy, proxy, 0);
  proxy->Fix();
  return isolate->heap()->undefined_value();
}


void Runtime::FreeArrayBuffer(Isolate* isolate,
                              JSArrayBuffer* phantom_array_buffer) {
  if (phantom_array_buffer->is_external()) return;

  size_t allocated_length = NumberToSize(
      isolate, phantom_array_buffer->byte_length());

  isolate->heap()->AdjustAmountOfExternalAllocatedMemory(
      -static_cast<intptr_t>(allocated_length));
  CHECK(V8::ArrayBufferAllocator() != NULL);
  V8::ArrayBufferAllocator()->Free(
      phantom_array_buffer->backing_store(),
      allocated_length);
}


void Runtime::SetupArrayBuffer(Isolate* isolate,
                               Handle<JSArrayBuffer> array_buffer,
                               bool is_external,
                               void* data,
                               size_t allocated_length) {
  ASSERT(array_buffer->GetInternalFieldCount() ==
      v8::ArrayBuffer::kInternalFieldCount);
  for (int i = 0; i < v8::ArrayBuffer::kInternalFieldCount; i++) {
    array_buffer->SetInternalField(i, Smi::FromInt(0));
  }
  array_buffer->set_backing_store(data);
  array_buffer->set_flag(Smi::FromInt(0));
  array_buffer->set_is_external(is_external);

  Handle<Object> byte_length =
      isolate->factory()->NewNumberFromSize(allocated_length);
  CHECK(byte_length->IsSmi() || byte_length->IsHeapNumber());
  array_buffer->set_byte_length(*byte_length);

  array_buffer->set_weak_next(isolate->heap()->array_buffers_list());
  isolate->heap()->set_array_buffers_list(*array_buffer);
  array_buffer->set_weak_first_view(isolate->heap()->undefined_value());
}


bool Runtime::SetupArrayBufferAllocatingData(
    Isolate* isolate,
    Handle<JSArrayBuffer> array_buffer,
    size_t allocated_length,
    bool initialize) {
  void* data;
  CHECK(V8::ArrayBufferAllocator() != NULL);
  if (allocated_length != 0) {
    if (initialize) {
      data = V8::ArrayBufferAllocator()->Allocate(allocated_length);
    } else {
      data =
        V8::ArrayBufferAllocator()->AllocateUninitialized(allocated_length);
    }
    if (data == NULL) return false;
  } else {
    data = NULL;
  }

  SetupArrayBuffer(isolate, array_buffer, false, data, allocated_length);

  isolate->heap()->AdjustAmountOfExternalAllocatedMemory(allocated_length);

  return true;
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_ArrayBufferInitialize) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 2);
  CONVERT_ARG_HANDLE_CHECKED(JSArrayBuffer, holder, 0);
  CONVERT_ARG_HANDLE_CHECKED(Object, byteLength, 1);
  size_t allocated_length;
  if (byteLength->IsSmi()) {
    allocated_length = Smi::cast(*byteLength)->value();
  } else {
    ASSERT(byteLength->IsHeapNumber());
    double value = HeapNumber::cast(*byteLength)->value();

    ASSERT(value >= 0);

    if (value > std::numeric_limits<size_t>::max()) {
      return isolate->Throw(
          *isolate->factory()->NewRangeError("invalid_array_buffer_length",
            HandleVector<Object>(NULL, 0)));
    }

    allocated_length = static_cast<size_t>(value);
  }

  if (!Runtime::SetupArrayBufferAllocatingData(isolate,
                                               holder, allocated_length)) {
      return isolate->Throw(*isolate->factory()->
          NewRangeError("invalid_array_buffer_length",
            HandleVector<Object>(NULL, 0)));
  }

  return *holder;
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_ArrayBufferGetByteLength) {
  SealHandleScope shs(isolate);
  ASSERT(args.length() == 1);
  CONVERT_ARG_CHECKED(JSArrayBuffer, holder, 0);
  return holder->byte_length();
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_ArrayBufferSliceImpl) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 3);
  CONVERT_ARG_HANDLE_CHECKED(JSArrayBuffer, source, 0);
  CONVERT_ARG_HANDLE_CHECKED(JSArrayBuffer, target, 1);
  CONVERT_DOUBLE_ARG_CHECKED(first, 2);
  size_t start = static_cast<size_t>(first);
  size_t target_length = NumberToSize(isolate, target->byte_length());

  if (target_length == 0) return isolate->heap()->undefined_value();

  ASSERT(NumberToSize(isolate, source->byte_length()) - target_length >= start);
  uint8_t* source_data = reinterpret_cast<uint8_t*>(source->backing_store());
  uint8_t* target_data = reinterpret_cast<uint8_t*>(target->backing_store());
  CopyBytes(target_data, source_data + start, target_length);
  return isolate->heap()->undefined_value();
}


enum TypedArrayId {
  // arrayIds below should be synchromized with typedarray.js natives.
  ARRAY_ID_UINT8 = 1,
  ARRAY_ID_INT8 = 2,
  ARRAY_ID_UINT16 = 3,
  ARRAY_ID_INT16 = 4,
  ARRAY_ID_UINT32 = 5,
  ARRAY_ID_INT32 = 6,
  ARRAY_ID_FLOAT32 = 7,
  ARRAY_ID_FLOAT64 = 8,
  ARRAY_ID_UINT8C = 9
};

static void ArrayIdToTypeAndSize(
    int arrayId, ExternalArrayType* array_type, size_t* element_size) {
  switch (arrayId) {
    case ARRAY_ID_UINT8:
      *array_type = kExternalUnsignedByteArray;
      *element_size = 1;
      break;
    case ARRAY_ID_INT8:
      *array_type = kExternalByteArray;
      *element_size = 1;
      break;
    case ARRAY_ID_UINT16:
      *array_type = kExternalUnsignedShortArray;
      *element_size = 2;
      break;
    case ARRAY_ID_INT16:
      *array_type = kExternalShortArray;
      *element_size = 2;
      break;
    case ARRAY_ID_UINT32:
      *array_type = kExternalUnsignedIntArray;
      *element_size = 4;
      break;
    case ARRAY_ID_INT32:
      *array_type = kExternalIntArray;
      *element_size = 4;
      break;
    case ARRAY_ID_FLOAT32:
      *array_type = kExternalFloatArray;
      *element_size = 4;
      break;
    case ARRAY_ID_FLOAT64:
      *array_type = kExternalDoubleArray;
      *element_size = 8;
      break;
    case ARRAY_ID_UINT8C:
      *array_type = kExternalPixelArray;
      *element_size = 1;
      break;
    default:
      UNREACHABLE();
  }
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_TypedArrayInitialize) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 5);
  CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, holder, 0);
  CONVERT_SMI_ARG_CHECKED(arrayId, 1);
  CONVERT_ARG_HANDLE_CHECKED(JSArrayBuffer, buffer, 2);
  CONVERT_ARG_HANDLE_CHECKED(Object, byte_offset_object, 3);
  CONVERT_ARG_HANDLE_CHECKED(Object, byte_length_object, 4);

  ASSERT(holder->GetInternalFieldCount() ==
      v8::ArrayBufferView::kInternalFieldCount);
  for (int i = 0; i < v8::ArrayBufferView::kInternalFieldCount; i++) {
    holder->SetInternalField(i, Smi::FromInt(0));
  }

  ExternalArrayType array_type = kExternalByteArray;  // Bogus initialization.
  size_t element_size = 1;  // Bogus initialization.
  ArrayIdToTypeAndSize(arrayId, &array_type, &element_size);

  holder->set_buffer(*buffer);
  holder->set_byte_offset(*byte_offset_object);
  holder->set_byte_length(*byte_length_object);

  size_t byte_offset = NumberToSize(isolate, *byte_offset_object);
  size_t byte_length = NumberToSize(isolate, *byte_length_object);
  ASSERT(byte_length % element_size == 0);
  size_t length = byte_length / element_size;

  Handle<Object> length_obj = isolate->factory()->NewNumberFromSize(length);
  holder->set_length(*length_obj);
  holder->set_weak_next(buffer->weak_first_view());
  buffer->set_weak_first_view(*holder);

  Handle<ExternalArray> elements =
      isolate->factory()->NewExternalArray(
          static_cast<int>(length), array_type,
          static_cast<uint8_t*>(buffer->backing_store()) + byte_offset);
  holder->set_elements(*elements);
  return isolate->heap()->undefined_value();
}


// Initializes a typed array from an array-like object.
// If an array-like object happens to be a typed array of the same type,
// initializes backing store using memove.
//
// Returns true if backing store was initialized or false otherwise.
RUNTIME_FUNCTION(MaybeObject*, Runtime_TypedArrayInitializeFromArrayLike) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 4);
  CONVERT_ARG_HANDLE_CHECKED(JSTypedArray, holder, 0);
  CONVERT_SMI_ARG_CHECKED(arrayId, 1);
  CONVERT_ARG_HANDLE_CHECKED(Object, source, 2);
  CONVERT_ARG_HANDLE_CHECKED(Object, length_obj, 3);

  ASSERT(holder->GetInternalFieldCount() ==
      v8::ArrayBufferView::kInternalFieldCount);
  for (int i = 0; i < v8::ArrayBufferView::kInternalFieldCount; i++) {
    holder->SetInternalField(i, Smi::FromInt(0));
  }

  ExternalArrayType array_type = kExternalByteArray;  // Bogus initialization.
  size_t element_size = 1;  // Bogus initialization.
  ArrayIdToTypeAndSize(arrayId, &array_type, &element_size);

  Handle<JSArrayBuffer> buffer = isolate->factory()->NewJSArrayBuffer();
  size_t length = NumberToSize(isolate, *length_obj);
  size_t byte_length = length * element_size;
  if (byte_length < length) {  // Overflow
    return isolate->Throw(*isolate->factory()->
          NewRangeError("invalid_array_buffer_length",
            HandleVector<Object>(NULL, 0)));
  }

  // We assume that the caller of this function will initialize holder
  // with the loop
  //      for(i = 0; i < length; i++) { holder[i] = source[i]; }
  // If source is a typed array, this loop will always run to completion,
  // so we are sure that the backing store will be initialized.
  // Otherwise, we do not know (the indexing operation might throw).
  // Hence we require zero initialization unless our source is a typed array.
  bool should_zero_initialize = !source->IsJSTypedArray();

  if (!Runtime::SetupArrayBufferAllocatingData(
        isolate, buffer, byte_length, should_zero_initialize)) {
    return isolate->Throw(*isolate->factory()->
          NewRangeError("invalid_array_buffer_length",
            HandleVector<Object>(NULL, 0)));
  }

  holder->set_buffer(*buffer);
  holder->set_byte_offset(Smi::FromInt(0));
  Handle<Object> byte_length_obj(
      isolate->factory()->NewNumberFromSize(byte_length));
  holder->set_byte_length(*byte_length_obj);
  holder->set_length(*length_obj);
  holder->set_weak_next(buffer->weak_first_view());
  buffer->set_weak_first_view(*holder);

  Handle<ExternalArray> elements =
      isolate->factory()->NewExternalArray(
          static_cast<int>(length), array_type,
          static_cast<uint8_t*>(buffer->backing_store()));
  holder->set_elements(*elements);

  if (source->IsJSTypedArray()) {
    Handle<JSTypedArray> typed_array(JSTypedArray::cast(*source));

    if (typed_array->type() == holder->type()) {
      uint8_t* backing_store =
        static_cast<uint8_t*>(
          JSArrayBuffer::cast(typed_array->buffer())->backing_store());
      size_t source_byte_offset =
          NumberToSize(isolate, typed_array->byte_offset());
      OS::MemCopy(
          buffer->backing_store(),
          backing_store + source_byte_offset,
          byte_length);
      return *isolate->factory()->true_value();
    } else {
      return *isolate->factory()->false_value();
    }
  }

  return *isolate->factory()->false_value();
}


#define TYPED_ARRAY_GETTER(getter, accessor) \
  RUNTIME_FUNCTION(MaybeObject*, Runtime_TypedArrayGet##getter) {             \
    HandleScope scope(isolate);                                               \
    ASSERT(args.length() == 1);                                               \
    CONVERT_ARG_HANDLE_CHECKED(Object, holder, 0);                            \
    if (!holder->IsJSTypedArray())                                            \
      return isolate->Throw(*isolate->factory()->NewTypeError(                \
          "not_typed_array", HandleVector<Object>(NULL, 0)));                 \
    Handle<JSTypedArray> typed_array(JSTypedArray::cast(*holder));            \
    return typed_array->accessor();                                           \
  }

TYPED_ARRAY_GETTER(Buffer, buffer)
TYPED_ARRAY_GETTER(ByteLength, byte_length)
TYPED_ARRAY_GETTER(ByteOffset, byte_offset)
TYPED_ARRAY_GETTER(Length, length)

#undef TYPED_ARRAY_GETTER

// Return codes for Runtime_TypedArraySetFastCases.
// Should be synchronized with typedarray.js natives.
enum TypedArraySetResultCodes {
  // Set from typed array of the same type.
  // This is processed by TypedArraySetFastCases
  TYPED_ARRAY_SET_TYPED_ARRAY_SAME_TYPE = 0,
  // Set from typed array of the different type, overlapping in memory.
  TYPED_ARRAY_SET_TYPED_ARRAY_OVERLAPPING = 1,
  // Set from typed array of the different type, non-overlapping.
  TYPED_ARRAY_SET_TYPED_ARRAY_NONOVERLAPPING = 2,
  // Set from non-typed array.
  TYPED_ARRAY_SET_NON_TYPED_ARRAY = 3
};


RUNTIME_FUNCTION(MaybeObject*, Runtime_TypedArraySetFastCases) {
  HandleScope scope(isolate);
  CONVERT_ARG_HANDLE_CHECKED(Object, target_obj, 0);
  CONVERT_ARG_HANDLE_CHECKED(Object, source_obj, 1);
  CONVERT_ARG_HANDLE_CHECKED(Object, offset_obj, 2);

  if (!target_obj->IsJSTypedArray())
    return isolate->Throw(*isolate->factory()->NewTypeError(
        "not_typed_array", HandleVector<Object>(NULL, 0)));

  if (!source_obj->IsJSTypedArray())
    return Smi::FromInt(TYPED_ARRAY_SET_NON_TYPED_ARRAY);

  Handle<JSTypedArray> target(JSTypedArray::cast(*target_obj));
  Handle<JSTypedArray> source(JSTypedArray::cast(*source_obj));
  size_t offset = NumberToSize(isolate, *offset_obj);
  size_t target_length = NumberToSize(isolate, target->length());
  size_t source_length = NumberToSize(isolate, source->length());
  size_t target_byte_length = NumberToSize(isolate, target->byte_length());
  size_t source_byte_length = NumberToSize(isolate, source->byte_length());
  if (offset > target_length ||
      offset + source_length > target_length ||
      offset + source_length < offset)  // overflow
    return isolate->Throw(*isolate->factory()->NewRangeError(
          "typed_array_set_source_too_large", HandleVector<Object>(NULL, 0)));

  size_t target_offset = NumberToSize(isolate, target->byte_offset());
  size_t source_offset = NumberToSize(isolate, source->byte_offset());
  uint8_t* target_base =
      static_cast<uint8_t*>(
        JSArrayBuffer::cast(target->buffer())->backing_store()) + target_offset;
  uint8_t* source_base =
      static_cast<uint8_t*>(
        JSArrayBuffer::cast(source->buffer())->backing_store()) + source_offset;

  // Typed arrays of the same type: use memmove.
  if (target->type() == source->type()) {
    memmove(target_base + offset * target->element_size(),
        source_base, source_byte_length);
    return Smi::FromInt(TYPED_ARRAY_SET_TYPED_ARRAY_SAME_TYPE);
  }

  // Typed arrays of different types over the same backing store
  if ((source_base <= target_base &&
        source_base + source_byte_length > target_base) ||
      (target_base <= source_base &&
        target_base + target_byte_length > source_base)) {
    // We do not support overlapping ArrayBuffers
    ASSERT(
      JSArrayBuffer::cast(target->buffer())->backing_store() ==
      JSArrayBuffer::cast(source->buffer())->backing_store());
    return Smi::FromInt(TYPED_ARRAY_SET_TYPED_ARRAY_OVERLAPPING);
  } else {  // Non-overlapping typed arrays
    return Smi::FromInt(TYPED_ARRAY_SET_TYPED_ARRAY_NONOVERLAPPING);
  }
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_DataViewInitialize) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 4);
  CONVERT_ARG_HANDLE_CHECKED(JSDataView, holder, 0);
  CONVERT_ARG_HANDLE_CHECKED(JSArrayBuffer, buffer, 1);
  CONVERT_ARG_HANDLE_CHECKED(Object, byte_offset, 2);
  CONVERT_ARG_HANDLE_CHECKED(Object, byte_length, 3);

  ASSERT(holder->GetInternalFieldCount() ==
      v8::ArrayBufferView::kInternalFieldCount);
  for (int i = 0; i < v8::ArrayBufferView::kInternalFieldCount; i++) {
    holder->SetInternalField(i, Smi::FromInt(0));
  }

  holder->set_buffer(*buffer);
  ASSERT(byte_offset->IsNumber());
  ASSERT(
      NumberToSize(isolate, buffer->byte_length()) >=
        NumberToSize(isolate, *byte_offset)
        + NumberToSize(isolate, *byte_length));
  holder->set_byte_offset(*byte_offset);
  ASSERT(byte_length->IsNumber());
  holder->set_byte_length(*byte_length);

  holder->set_weak_next(buffer->weak_first_view());
  buffer->set_weak_first_view(*holder);

  return isolate->heap()->undefined_value();
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_DataViewGetBuffer) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 1);
  CONVERT_ARG_HANDLE_CHECKED(JSDataView, data_view, 0);
  return data_view->buffer();
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_DataViewGetByteOffset) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 1);
  CONVERT_ARG_HANDLE_CHECKED(JSDataView, data_view, 0);
  return data_view->byte_offset();
}


RUNTIME_FUNCTION(MaybeObject*, Runtime_DataViewGetByteLength) {
  HandleScope scope(isolate);
  ASSERT(args.length() == 1);
  CONVERT_ARG_HANDLE_CHECKED(JSDataView, data_view, 0);
  return data_view->byte_length();
}


inline static bool NeedToFlipBytes(bool is_little_endian) {
#ifdef V8_TARGET_LITTLE_ENDIAN
  return !is_little_endian;
#else
  return is_little_endian;
#endif
}


template<int n>
inline void CopyBytes(uint8_t* target, uint8_t* source) {
  for (int i = 0; i < n; i++) {
    *(target++) = *(source++);
  }
}


template<int n>
inline void FlipBytes(uint8_t* target, uint8_t* source) {
  source = source + (n-1);
  for (int i = 0; i < n; i++) {
    *(target++) = *(source--);
  }
}


template<typename T>
inline static bool DataViewGetValue(
    Isolate* isolate,
    Handle<JSDataView> data_view,
    Handle<Object> byte_offset_obj,
    bool is_little_endian,
    T* result) {
  size_t byte_offset = NumberToSize(isolate, *byte_offset_obj);
  Handle<JSArrayBuffer> buffer(JSArrayBuffer::cast(data_view->buffer()));

  size_t data_view_byte_offset =
      NumberToSize(isolate, data_view->byte_offset());
  size_t data_view_byte_length =
      NumberToSize(isolate, data_view->byte_length());
  if (byte_offset + sizeof(T) > data_view_byte_length ||
      byte_offset + sizeof(T) < byte_offset)  {  // overflow
    return false;
  }

  union Value {
    T data;
    uint8_t bytes[sizeof(T)];
  };

  Value value;
  size_t buffer_offset = data_view_byte_offset + byte_offset;
  ASSERT(
      NumberToSize(isolate, buffer->byte_length())
      >= buffer_offset + sizeof(T));
  uint8_t* source =
        static_cast<uint8_t*>(buffer->backing_store()) + buffer_offset;
  if (NeedToFlipBytes(is_little_endian)) {
    FlipBytes<sizeof(T)>(value.bytes, source);
  } else {
    CopyBytes<sizeof(T)>(value.bytes, source);
  }
  *result = value.data;
  return true;
}


template<typename T>
static bool DataViewSetValue(
    Isolate* isolate,
    Handle<JSDataView> data_view,
    Handle<Object> byte_offset_obj,
    bool is_little_endian,
    T data) {
  size_t byte_offset = NumberToSize(isolate, *byte_offset_obj);
  Handle<JSArrayBuffer> buffer(JSArrayBuffer::cast(data_view->buffer()));

  size_t data_view_byte_offset =
      NumberToSize(isolate, data_view->byte_offset());
  size_t data_view_byte_length =
      NumberToSize(isolate, data_view->byte_length());
  if (byte_offset + sizeof(T) > data_view_byte_length ||
      byte_offset + sizeof(T) < byte_offset)  {  // overflow
    return false;
  }

  union Value {
    T data;
    uint8_t bytes[sizeof(T)];
  };

  Value value;
  value.data = data;
  size_t buffer_offset = data_view_byte_offset + byte_offset;
  ASSERT(
      NumberToSize(isolate, buffer->byte_length())
      >= buffer_offset + sizeof(T));
  uint8_t* target =
        static_cast<uint8_t*>(buffer->backing_store()) + buffer_offset;
  if (NeedToFlipBytes(is_little_endian)) {
    FlipBytes<sizeof(T)>(target, value.bytes);
  } else {
    CopyBytes<sizeof(T)>(target, value.bytes);
  }
  return true;
}


#define DATA_VIEW_GETTER(TypeName, Type, Converter)                           \
  RUNTIME_FUNCTION(MaybeObject*, Runtime_DataViewGet##TypeName) {             \
    HandleScope scope(isolate);                                               \
    ASSERT(args.length() == 3);                                               \
    CONVERT_ARG_HANDLE_CHECKED(JSDataView, holder, 0);                        \
    CONVERT_ARG_HANDLE_CHECKED(Object, offset, 1);                            \
    CONVERT_BOOLEAN_ARG_CHECKED(is_little_endian, 2);                         \
    Type result;                                                              \
    if (DataViewGetValue(                                                     \
          isolate, holder, offset, is_little_endian, &result)) {              \
      return isolate->heap()->Converter(result);                              \
    } else {                                                                  \
      return isolate->Throw(*isolate->factory()->NewRangeError(               \
          "invalid_data_view_accessor_offset",                                \
          HandleVector<Object>(NULL, 0)));                                    \
    }                                                                         \
  }

DATA_VIEW_GETTER(Uint8, uint8_t, NumberFromUint32)
DATA_VIEW_GETTER(Int8, int8_t, NumberFromInt32)
DATA_VIEW_GETTER(Uint16, uint16_t, NumberFromUint32)
DATA_VIEW_GETTER(Int16, int16_t, NumberFromInt32)
DATA_VIEW_GETTER(Uint32, uint32_t, NumberFromUint32)
DATA_VIEW_GETTER(Int32, int32_t, NumberFromInt32)
DATA_VIEW_GETTER(Float32, float, NumberFromDouble)
DATA_VIEW_GETTER(Float64, double, NumberFromDouble)

#undef DATA_VIEW_GETTER


template <typename T>
static T DataViewConvertValue(double value);


template <>
int8_t DataViewConvertValue<int8_t>(double value) {
  return static_cast<int8_t>(DoubleToInt32(value));
}


template <>
int16_t DataViewConvertValue<int16_t>(double value) {
  return static_cast<int16_t>(DoubleToInt32(value));
}


template <>
int32_t DataViewConvertValue<int32_t>(double value) {
  return DoubleToInt32(value);
}


template <>
uint8_t DataViewConvertValue<uint8_t>(double value) {
  return static_cast<uint8_t>(DoubleToUint32(value));
}


template <>
uint16_t DataViewConvertValue<uint16_t>(double value) {
  return static_cast<uint16_t>(DoubleToUint32(value));
}


template <>
uint32_t DataViewConvertValue<uint32_t>(double value) {
  return DoubleToUint32(value);
}


template <>
float DataViewConvertValue<float>(double value) {
  return static_cast<float>(value);
}


template <>
double DataViewConvertValue<double>(double value) {
  return value;
}


#define DATA_VIEW_SETTER(TypeName, Type)                                      \
  RUNTIME_FUNCTION(MaybeObject*, Runtime_DataViewSet##TypeName) {             \
    HandleScope scope(isolate);                                               \
    ASSERT(args.length() == 4);                                               \
    CONVERT_ARG_HANDLE_CHECKED(JSDataView, holder, 0);                        \
    CONVERT_ARG_HANDLE_CHECKED(Object, offset, 1);                            \
    CONVERT_ARG_HANDLE_CHECKED(Object, value, 2);                             \
    CONVERT_BOOLEAN_ARG_CHECKED(is_little_endian, 3);                         \
    Type v = DataViewConvertValue<Type>(value->Number());                     \
    if (DataViewSetValue(                                                     \
          isolate, holder, offset, is_little_endian, v)) {                    \
      return isolate->heap()->undefined_value();                              \
    } else {                                                                  \
      return isolate->Throw(*isolate->factory()->NewRangeError(               \
          …