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