/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=8 sts=4 et sw=4 tw=99:
 * 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/. */

#ifndef vm_Shape_inl_h
#define vm_Shape_inl_h

#include "vm/Shape.h"

#include "mozilla/TypeTraits.h"

#include "jsobj.h"

#include "gc/Allocator.h"
#include "vm/Interpreter.h"
#include "vm/TypedArrayCommon.h"

#include "jsatominlines.h"
#include "jscntxtinlines.h"

namespace js {

inline
AutoKeepShapeTables::AutoKeepShapeTables(ExclusiveContext* cx)
  : cx_(cx),
    prev_(cx->zone()->keepShapeTables())
{
    cx->zone()->setKeepShapeTables(true);
}

inline
AutoKeepShapeTables::~AutoKeepShapeTables()
{
    cx_->zone()->setKeepShapeTables(prev_);
}

inline
StackBaseShape::StackBaseShape(ExclusiveContext* cx, const Class* clasp, uint32_t objectFlags)
  : flags(objectFlags),
    clasp(clasp)
{}

inline Shape*
Shape::search(ExclusiveContext* cx, jsid id)
{
    return search(cx, this, id);
}

MOZ_ALWAYS_INLINE bool
Shape::maybeCreateTableForLookup(ExclusiveContext* cx)
{
    if (hasTable())
        return true;

    if (!inDictionary() && numLinearSearches() < LINEAR_SEARCHES_MAX) {
        incrementNumLinearSearches();
        return true;
    }

    if (!isBigEnoughForAShapeTable())
        return true;

    return Shape::hashify(cx, this);
}

template<MaybeAdding Adding>
/* static */ inline bool
Shape::search(ExclusiveContext* cx, Shape* start, jsid id, const AutoKeepShapeTables& keep,
              Shape** pshape, ShapeTable::Entry** pentry)
{
    if (start->inDictionary()) {
        ShapeTable* table = start->ensureTableForDictionary(cx, keep);
        if (!table)
            return false;
        *pentry = &table->search<Adding>(id, keep);
        *pshape = (*pentry)->shape();
        return true;
    }

    *pentry = nullptr;
    *pshape = Shape::search<Adding>(cx, start, id);
    return true;
}

template<MaybeAdding Adding>
/* static */ inline Shape*
Shape::search(ExclusiveContext* cx, Shape* start, jsid id)
{
    if (start->maybeCreateTableForLookup(cx)) {
        JS::AutoCheckCannotGC nogc;
        if (ShapeTable* table = start->maybeTable(nogc)) {
            ShapeTable::Entry& entry = table->search<Adding>(id, nogc);
            return entry.shape();
        }
    } else {
        // Just do a linear search.
        cx->recoverFromOutOfMemory();
    }

    return start->searchLinear(id);
}

inline Shape*
Shape::new_(ExclusiveContext* cx, Handle<StackShape> other, uint32_t nfixed)
{
    Shape* shape = other.isAccessorShape()
                   ? js::Allocate<AccessorShape>(cx)
                   : js::Allocate<Shape>(cx);
    if (!shape) {
        ReportOutOfMemory(cx);
        return nullptr;
    }

    if (other.isAccessorShape())
        new (shape) AccessorShape(other, nfixed);
    else
        new (shape) Shape(other, nfixed);

    return shape;
}

inline void
Shape::updateBaseShapeAfterMovingGC()
{
    BaseShape* base = base_.unbarrieredGet();
    if (IsForwarded(base))
        base_.unsafeSet(Forwarded(base));
}

template<class ObjectSubclass>
/* static */ inline bool
EmptyShape::ensureInitialCustomShape(ExclusiveContext* cx, Handle<ObjectSubclass*> obj)
{
    static_assert(mozilla::IsBaseOf<JSObject, ObjectSubclass>::value,
                  "ObjectSubclass must be a subclass of JSObject");

    // If the provided object has a non-empty shape, it was given the cached
    // initial shape when created: nothing to do.
    if (!obj->empty())
        return true;

    // If no initial shape was assigned, do so.
    RootedShape shape(cx, ObjectSubclass::assignInitialShape(cx, obj));
    if (!shape)
        return false;
    MOZ_ASSERT(!obj->empty());

    // If the object is a standard prototype -- |RegExp.prototype|,
    // |String.prototype|, |RangeError.prototype|, &c. -- GlobalObject.cpp's
    // |CreateBlankProto| marked it as a delegate.  These are the only objects
    // of this class that won't use the standard prototype, and there's no
    // reason to pollute the initial shape cache with entries for them.
    if (obj->isDelegate())
        return true;

    // Cache the initial shape for non-prototype objects, however, so that
    // future instances will begin life with that shape.
    RootedObject proto(cx, obj->staticPrototype());
    EmptyShape::insertInitialShape(cx, shape, proto);
    return true;
}

inline
AutoRooterGetterSetter::Inner::Inner(ExclusiveContext* cx, uint8_t attrs,
                                     GetterOp* pgetter_, SetterOp* psetter_)
  : CustomAutoRooter(cx), attrs(attrs),
    pgetter(pgetter_), psetter(psetter_)
{}

inline
AutoRooterGetterSetter::AutoRooterGetterSetter(ExclusiveContext* cx, uint8_t attrs,
                                               GetterOp* pgetter, SetterOp* psetter
                                               MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL)
{
    if (attrs & (JSPROP_GETTER | JSPROP_SETTER))
        inner.emplace(cx, attrs, pgetter, psetter);
    MOZ_GUARD_OBJECT_NOTIFIER_INIT;
}

inline
AutoRooterGetterSetter::AutoRooterGetterSetter(ExclusiveContext* cx, uint8_t attrs,
                                               JSNative* pgetter, JSNative* psetter
                                               MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL)
{
    if (attrs & (JSPROP_GETTER | JSPROP_SETTER)) {
        inner.emplace(cx, attrs, reinterpret_cast<GetterOp*>(pgetter),
                      reinterpret_cast<SetterOp*>(psetter));
    }
    MOZ_GUARD_OBJECT_NOTIFIER_INIT;
}

static inline uint8_t
GetShapeAttributes(JSObject* obj, Shape* shape)
{
    MOZ_ASSERT(obj->isNative());

    if (IsImplicitDenseOrTypedArrayElement(shape)) {
        if (obj->is<TypedArrayObject>())
            return JSPROP_ENUMERATE | JSPROP_PERMANENT;
        return obj->as<NativeObject>().getElementsHeader()->elementAttributes();
    }

    return shape->attributes();
}

} /* namespace js */

#endif /* vm_Shape_inl_h */