v8/src/property-descriptor.h
bmeurer 8e8bd866a4 [runtime] Introduce maps for the likely cases of FromPropertyDescriptor.
This change improves performance for the common case of
Object.getOwnPropertyDescriptor by up 3x-4x, where we just
return a property descriptor object for a regular data or
accessor property.

CQ_INCLUDE_TRYBOTS=tryserver.chromium.win:win_chromium_rel_ng
R=yangguo@chromium.org

Committed: https://crrev.com/ffa9e82235b20c523ebb1151c6196bc6232296b9
Cr-Commit-Position: refs/heads/master@{#33398}

Review URL: https://codereview.chromium.org/1607943003

Cr-Commit-Position: refs/heads/master@{#33415}
2016-01-20 19:04:40 +00:00

134 lines
3.8 KiB
C++

// Copyright 2015 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.
#ifndef V8_PROPERTY_DESCRIPTOR_H_
#define V8_PROPERTY_DESCRIPTOR_H_
#include "src/handles.h"
#include "src/property-details.h"
namespace v8 {
namespace internal {
class Isolate;
class Object;
class PropertyDescriptor {
public:
PropertyDescriptor()
: enumerable_(false),
has_enumerable_(false),
configurable_(false),
has_configurable_(false),
writable_(false),
has_writable_(false) {}
// ES6 6.2.4.1
static bool IsAccessorDescriptor(PropertyDescriptor* desc) {
return desc->has_get() || desc->has_set();
}
// ES6 6.2.4.2
static bool IsDataDescriptor(PropertyDescriptor* desc) {
return desc->has_value() || desc->has_writable();
}
// ES6 6.2.4.3
static bool IsGenericDescriptor(PropertyDescriptor* desc) {
return !IsAccessorDescriptor(desc) && !IsDataDescriptor(desc);
}
// ES6 6.2.4.4
Handle<Object> ToObject(Isolate* isolate);
// ES6 6.2.4.5
static bool ToPropertyDescriptor(Isolate* isolate, Handle<Object> obj,
PropertyDescriptor* desc);
// ES6 6.2.4.6
static void CompletePropertyDescriptor(Isolate* isolate,
PropertyDescriptor* desc);
bool is_empty() const {
return !has_enumerable() && !has_configurable() && !has_writable() &&
!has_value() && !has_get() && !has_set();
}
bool IsRegularAccessorProperty() const {
return has_configurable() && has_enumerable() && !has_value() &&
!has_writable() && has_get() && has_set();
}
bool IsRegularDataProperty() const {
return has_configurable() && has_enumerable() && has_value() &&
has_writable() && !has_get() && !has_set();
}
bool enumerable() const { return enumerable_; }
void set_enumerable(bool enumerable) {
enumerable_ = enumerable;
has_enumerable_ = true;
}
bool has_enumerable() const { return has_enumerable_; }
bool configurable() const { return configurable_; }
void set_configurable(bool configurable) {
configurable_ = configurable;
has_configurable_ = true;
}
bool has_configurable() const { return has_configurable_; }
Handle<Object> value() const { return value_; }
void set_value(Handle<Object> value) { value_ = value; }
bool has_value() const { return !value_.is_null(); }
bool writable() const { return writable_; }
void set_writable(bool writable) {
writable_ = writable;
has_writable_ = true;
}
bool has_writable() const { return has_writable_; }
Handle<Object> get() const { return get_; }
void set_get(Handle<Object> get) { get_ = get; }
bool has_get() const { return !get_.is_null(); }
Handle<Object> set() const { return set_; }
void set_set(Handle<Object> set) { set_ = set; }
bool has_set() const { return !set_.is_null(); }
Handle<Object> name() const { return name_; }
void set_name(Handle<Object> name) { name_ = name; }
PropertyAttributes ToAttributes() {
return static_cast<PropertyAttributes>(
(has_enumerable() && !enumerable() ? DONT_ENUM : NONE) |
(has_configurable() && !configurable() ? DONT_DELETE : NONE) |
(has_writable() && !writable() ? READ_ONLY : NONE));
}
private:
bool enumerable_ : 1;
bool has_enumerable_ : 1;
bool configurable_ : 1;
bool has_configurable_ : 1;
bool writable_ : 1;
bool has_writable_ : 1;
Handle<Object> value_;
Handle<Object> get_;
Handle<Object> set_;
Handle<Object> name_;
// Some compilers (Xcode 5.1, ARM GCC 4.9) insist on having a copy
// constructor for std::vector<PropertyDescriptor>, so we can't
// DISALLOW_COPY_AND_ASSIGN(PropertyDescriptor); here.
};
} // namespace internal
} // namespace v8
#endif // V8_PROPERTY_DESCRIPTOR_H_