Source/JavaScriptCore/runtime/JSAsyncGeneratorFunction.h

/*
 * Copyright (C) 2017 Oleksandr Skachkov <gskachkov@gmail.com>.
 * Copyright (C) 2018 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#pragma once

#include "JSFunction.h"

namespace JSC {

class JSAsyncGeneratorFunction final : public JSFunction {
    friend class JIT;
    friend class VM;
public:
    using Base = JSFunction;

    const static unsigned StructureFlags = Base::StructureFlags;

    template<typename CellType, SubspaceAccess>
    static IsoSubspace* subspaceFor(VM& vm)
    {
        return &vm.functionSpace;
    }

    DECLARE_EXPORT_INFO;

    static JSAsyncGeneratorFunction* create(VM&, FunctionExecutable*, JSScope*);
    static JSAsyncGeneratorFunction* create(VM&, FunctionExecutable*, JSScope*, Structure*);
    static JSAsyncGeneratorFunction* createWithInvalidatedReallocationWatchpoint(VM&, FunctionExecutable*, JSScope*);

    static size_t allocationSize(size_t inlineCapacity)
    {
        ASSERT_UNUSED(inlineCapacity, !inlineCapacity);
        return sizeof(JSAsyncGeneratorFunction);
    }

    static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
    {
        ASSERT(globalObject);
        return Structure::create(vm, globalObject, prototype, TypeInfo(JSFunctionType, StructureFlags), info());
    }

    enum class AsyncGeneratorState : int32_t {
        Completed = -1,
        Executing = -2,
        SuspendedStart = -3,
        SuspendedYield = -4,
        AwaitingReturn = -5
    };
    
    enum class AsyncGeneratorSuspendReason : int32_t {
        None = 0,
        Yield = -1,
        Await = -2
    };
private:
    JSAsyncGeneratorFunction(VM&, FunctionExecutable*, JSScope*, Structure*);

    static JSAsyncGeneratorFunction* createImpl(VM&, FunctionExecutable*, JSScope*, Structure*);
};
static_assert(sizeof(JSAsyncGeneratorFunction) == sizeof(JSFunction), "Some subclasses of JSFunction should be the same size to share IsoSubspace");

} // namespace JSC