зеркало из https://github.com/mozilla/gecko-dev.git
68 строки
1.7 KiB
C++
68 строки
1.7 KiB
C++
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
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* vim: set ts=8 sts=2 et sw=2 tw=80:
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* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/*
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* Shadow definition of |JSObject| innards. (|js::NativeObject| is more
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* accurate, but portions can sometimes be used in some non-native objects.) Do
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* not use this directly!
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*/
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#ifndef js_shadow_Object_h
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#define js_shadow_Object_h
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#include <stddef.h> // size_t
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#include "js/shadow/Shape.h" // JS::shadow::Shape
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#include "js/Value.h" // JS::Value
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class JS_PUBLIC_API JSObject;
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namespace JS {
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class JS_PUBLIC_API Value;
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namespace shadow {
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/**
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* This layout is shared by all native objects. For non-native objects, the
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* shape may always be accessed safely, and other members may be as well,
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* depending on the object's specific layout.
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*/
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struct Object {
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shadow::Shape* shape;
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#ifndef JS_64BIT
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uint32_t padding_;
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#endif
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Value* slots;
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void* _1;
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static constexpr size_t MAX_FIXED_SLOTS = 16;
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size_t numFixedSlots() const {
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return (shape->immutableFlags & shadow::Shape::FIXED_SLOTS_MASK) >>
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shadow::Shape::FIXED_SLOTS_SHIFT;
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}
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Value* fixedSlots() const {
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auto address = reinterpret_cast<uintptr_t>(this);
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return reinterpret_cast<JS::Value*>(address + sizeof(shadow::Object));
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}
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Value& slotRef(size_t slot) const {
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size_t nfixed = numFixedSlots();
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if (slot < nfixed) {
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return fixedSlots()[slot];
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}
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return slots[slot - nfixed];
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}
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};
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} // namespace shadow
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} // namespace JS
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#endif // js_shadow_Object_h
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