Everywhere: Hoist the Libraries folder to the top-level

Author: https://github.com/trflynn89
Commit: 93712b24bf
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2256
Reviewed-by: https://github.com/sideshowbarker

Libraries/LibJS/Heap/Cell.h

@@ -0,0 +1,195 @@
+/*
+ * Copyright (c) 2020-2024, Andreas Kling <andreas@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Badge.h>
+#include <AK/Format.h>
+#include <AK/Forward.h>
+#include <AK/HashMap.h>
+#include <AK/Noncopyable.h>
+#include <AK/StringView.h>
+#include <AK/Weakable.h>
+#include <LibJS/Forward.h>
+#include <LibJS/Heap/GCPtr.h>
+#include <LibJS/Heap/Internals.h>
+
+namespace JS {
+
+// This instrumentation tells analysis tooling to ignore a potentially mis-wrapped GC-allocated member variable
+// It should only be used when the lifetime of the GC-allocated member is always longer than the object
+#if defined(AK_COMPILER_CLANG)
+#    define IGNORE_GC [[clang::annotate("serenity::ignore_gc")]]
+#else
+#    define IGNORE_GC
+#endif
+
+#define JS_CELL(class_, base_class)                \
+public:                                            \
+    using Base = base_class;                       \
+    virtual StringView class_name() const override \
+    {                                              \
+        return #class_##sv;                        \
+    }                                              \
+    friend class JS::Heap;
+
+class Cell : public Weakable<Cell> {
+    AK_MAKE_NONCOPYABLE(Cell);
+    AK_MAKE_NONMOVABLE(Cell);
+
+public:
+    virtual void initialize(Realm&);
+    virtual ~Cell() = default;
+
+    bool is_marked() const { return m_mark; }
+    void set_marked(bool b) { m_mark = b; }
+
+    enum class State : bool {
+        Live,
+        Dead,
+    };
+
+    State state() const { return m_state; }
+    void set_state(State state) { m_state = state; }
+
+    virtual StringView class_name() const = 0;
+
+    class Visitor {
+    public:
+        void visit(Cell* cell)
+        {
+            if (cell)
+                visit_impl(*cell);
+        }
+
+        void visit(Cell& cell)
+        {
+            visit_impl(cell);
+        }
+
+        template<typename T>
+        void visit(GCPtr<T> cell)
+        {
+            if (cell)
+                visit_impl(const_cast<RemoveConst<T>&>(*cell.ptr()));
+        }
+
+        template<typename T>
+        void visit(NonnullGCPtr<T> cell)
+        {
+            visit_impl(const_cast<RemoveConst<T>&>(*cell.ptr()));
+        }
+
+        template<typename T>
+        void visit(ReadonlySpan<T> span)
+        {
+            for (auto& value : span)
+                visit(value);
+        }
+
+        template<typename T>
+        void visit(Span<T> span)
+        {
+            for (auto& value : span)
+                visit(value);
+        }
+
+        template<typename T>
+        void visit(Vector<T> const& vector)
+        {
+            for (auto& value : vector)
+                visit(value);
+        }
+
+        template<typename T>
+        void visit(HashTable<T> const& table)
+        {
+            for (auto& value : table)
+                visit(value);
+        }
+
+        template<typename T>
+        void visit(OrderedHashTable<T> const& table)
+        {
+            for (auto& value : table)
+                visit(value);
+        }
+
+        template<typename K, typename V, typename T>
+        void visit(HashMap<K, V, T> const& map)
+        {
+            for (auto& it : map) {
+                if constexpr (requires { visit(it.key); })
+                    visit(it.key);
+                if constexpr (requires { visit(it.value); })
+                    visit(it.value);
+            }
+        }
+
+        template<typename K, typename V, typename T>
+        void visit(OrderedHashMap<K, V, T> const& map)
+        {
+            for (auto& it : map) {
+                if constexpr (requires { visit(it.key); })
+                    visit(it.key);
+                if constexpr (requires { visit(it.value); })
+                    visit(it.value);
+            }
+        }
+
+        void visit(Value value);
+
+        // Allow explicitly ignoring a GC-allocated member in a visit_edges implementation instead
+        // of just not using it.
+        template<typename T>
+        void ignore(T const&)
+        {
+        }
+
+        virtual void visit_possible_values(ReadonlyBytes) = 0;
+
+    protected:
+        virtual void visit_impl(Cell&) = 0;
+        virtual ~Visitor() = default;
+    };
+
+    virtual void visit_edges(Visitor&) { }
+
+    // This will be called on unmarked objects by the garbage collector in a separate pass before destruction.
+    virtual void finalize() { }
+
+    // This allows cells to survive GC by choice, even if nothing points to them.
+    // It's used to implement special rules in the web platform.
+    // NOTE: Cells must call set_overrides_must_survive_garbage_collection() for this to be honored.
+    virtual bool must_survive_garbage_collection() const { return false; }
+
+    bool overrides_must_survive_garbage_collection(Badge<Heap>) const { return m_overrides_must_survive_garbage_collection; }
+
+    ALWAYS_INLINE Heap& heap() const { return HeapBlockBase::from_cell(this)->heap(); }
+    ALWAYS_INLINE VM& vm() const { return bit_cast<HeapBase*>(&heap())->vm(); }
+
+protected:
+    Cell() = default;
+
+    void set_overrides_must_survive_garbage_collection(bool b) { m_overrides_must_survive_garbage_collection = b; }
+
+private:
+    bool m_mark : 1 { false };
+    bool m_overrides_must_survive_garbage_collection : 1 { false };
+    State m_state : 1 { State::Live };
+};
+
+}
+
+template<>
+struct AK::Formatter<JS::Cell> : AK::Formatter<FormatString> {
+    ErrorOr<void> format(FormatBuilder& builder, JS::Cell const* cell)
+    {
+        if (!cell)
+            return builder.put_string("Cell{nullptr}"sv);
+        return Formatter<FormatString>::format(builder, "{}({})"sv, cell->class_name(), cell);
+    }
+};