[runtime] Introduce dedicated JSBoundFunction to represent bound functions.

src/factory.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/factory.h"
 
 #include "src/allocation-site-scopes.h"
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
 #include "src/conversions.h"
@@ skipping 1176 matching lines @@
                                         PretenureFlag pretenure) {
   AllocationSpace space = pretenure == TENURED ? OLD_SPACE : NEW_SPACE;
   Handle<JSFunction> function = New<JSFunction>(map, space);
 
   function->initialize_properties();
   function->initialize_elements();
   function->set_shared(*info);
   function->set_code(info->code());
   function->set_context(*context);
   function->set_prototype_or_initial_map(*the_hole_value());
-  function->set_literals_or_bindings(*empty_fixed_array());
+  function->set_literals(LiteralsArray::cast(*empty_fixed_array()));
   function->set_next_function_link(*undefined_value(), SKIP_WRITE_BARRIER);
   isolate()->heap()->InitializeJSObjectBody(*function, *map, JSFunction::kSize);
   return function;
 }
 
 
 Handle<JSFunction> Factory::NewFunction(Handle<Map> map,
                                         Handle<String> name,
                                         MaybeHandle<Code> code) {
   Handle<Context> context(isolate()->native_context());
@@ skipping 144 matching lines @@
       context->native_context(), BailoutId::None());
   if (cached.code != nullptr) {
     // Caching of optimized code enabled and optimized code found.
     DCHECK(!cached.code->marked_for_deoptimization());
     DCHECK(result->shared()->is_compiled());
     result->ReplaceCode(cached.code);
   }
 
   if (cached.literals != nullptr) {
     result->set_literals(cached.literals);
-
-  } else if (!info->bound()) {
+  } else {
     int number_of_literals = info->num_literals();
     Handle<LiteralsArray> literals =
         LiteralsArray::New(isolate(), handle(info->feedback_vector()),
                            number_of_literals, pretenure);
     result->set_literals(*literals);
 
     // Cache context-specific literals.
     Handle<Context> native_context(context->native_context());
     SharedFunctionInfo::AddLiteralsToOptimizedCodeMap(info, native_context,
                                                       literals);
@@ skipping 561 matching lines @@
 
 Handle<JSDataView> Factory::NewJSDataView(Handle<JSArrayBuffer> buffer,
                                           size_t byte_offset,
                                           size_t byte_length) {
   Handle<JSDataView> obj = NewJSDataView();
   SetupArrayBufferView(isolate(), obj, buffer, byte_offset, byte_length);
   return obj;
 }
 
 
+MaybeHandle<JSBoundFunction> Factory::NewJSBoundFunction(
+    Handle<JSReceiver> target_function, Handle<Object> bound_this,
+    Vector<Handle<Object>> bound_args) {
+  DCHECK(target_function->IsCallable());
+  STATIC_ASSERT(Code::kMaxArguments <= FixedArray::kMaxLength);
+  if (bound_args.length() >= Code::kMaxArguments) {
+    THROW_NEW_ERROR(isolate(),
+                    NewRangeError(MessageTemplate::kTooManyArguments),
+                    JSBoundFunction);
+  }
+
+  // Determine the prototype of the {target_function}.
+  Handle<Object> prototype;
+  ASSIGN_RETURN_ON_EXCEPTION(isolate(), prototype,
+                             Object::GetPrototype(isolate(), target_function),
+                             JSBoundFunction);
+
+  // Create the [[BoundArguments]] for the result.
+  Handle<FixedArray> bound_arguments;
+  if (bound_args.length() == 0) {
+    bound_arguments = empty_fixed_array();
+  } else {
+    bound_arguments = NewFixedArray(bound_args.length());
+    for (int i = 0; i < bound_args.length(); ++i) {
+      bound_arguments->set(i, *bound_args[i]);
+    }
+  }
+
+  // Setup the map for the JSBoundFunction instance.
+  Handle<Map> map = handle(
+      target_function->IsConstructor()
+          ? isolate()->native_context()->bound_function_with_constructor_map()
+          : isolate()
+                ->native_context()
+                ->bound_function_without_constructor_map(),
+      isolate());
+  if (map->prototype() != *prototype) {
+    map = Map::TransitionToPrototype(map, prototype, REGULAR_PROTOTYPE);
+  }
+  DCHECK_EQ(target_function->IsConstructor(), map->is_constructor());
+
+  // Setup the JSBoundFunction instance.
+  Handle<JSBoundFunction> result =
+      Handle<JSBoundFunction>::cast(NewJSObjectFromMap(map));
+  result->set_bound_target_function(*target_function);
+  result->set_bound_this(*bound_this);
+  result->set_bound_arguments(*bound_arguments);
+  result->set_creation_context(*isolate()->native_context());
+  result->set_length(Smi::FromInt(0));
+  result->set_name(*undefined_value(), SKIP_WRITE_BARRIER);
+  return result;
+}
+
+
 // ES6 section 9.5.15 ProxyCreate (target, handler)
 Handle<JSProxy> Factory::NewJSProxy(Handle<JSReceiver> target,
                                     Handle<JSReceiver> handler) {
   // Allocate the proxy object.
   Handle<Map> map;
   if (target->IsCallable()) {
     if (target->IsConstructor()) {
       map = Handle<Map>(isolate()->proxy_constructor_map());
     } else {
       map = Handle<Map>(isolate()->proxy_callable_map());
@@ skipping 368 matching lines @@
 }
 
 
 Handle<Object> Factory::ToBoolean(bool value) {
   return value ? true_value() : false_value();
 }
 
 
 }  // namespace internal
 }  // namespace v8