Source/JavaScriptCore/wasm/js/JSWebAssemblyCodeBlock.h

/*
 * Copyright (C) 2017-2019 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. ``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
 * 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

#if ENABLE(WEBASSEMBLY)

#include "CallLinkInfo.h"
#include "JSCast.h"
#include "PromiseDeferredTimer.h"
#include "Structure.h"
#include "WasmCallee.h"
#include "WasmFormat.h"
#include "WasmModule.h"
#include <wtf/Bag.h>
#include <wtf/Ref.h>
#include <wtf/Vector.h>

namespace JSC {

class JSWebAssemblyMemory;

namespace Wasm {
class Plan;
}

class JSWebAssemblyCodeBlock final : public JSCell {
public:
    typedef JSCell Base;
    static constexpr unsigned StructureFlags = Base::StructureFlags | StructureIsImmortal;

    static JSWebAssemblyCodeBlock* create(VM&, Ref<Wasm::CodeBlock>, const Wasm::ModuleInformation&);
    static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
    {
        return Structure::create(vm, globalObject, prototype, TypeInfo(CellType, StructureFlags), info());
    }

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

    Wasm::CodeBlock& codeBlock() { return m_codeBlock.get(); }
    
    MacroAssemblerCodePtr<WasmEntryPtrTag> wasmToEmbedderStub(size_t importFunctionNum) { return m_wasmToJSExitStubs[importFunctionNum].code(); }

    void finishCreation(VM&);

    void clearJSCallICs(VM&);

    bool runnable() const { return !m_errorMessage; }

    String errorMessage()
    {
        ASSERT(!runnable());
        return m_errorMessage;
    }

    void finalizeUnconditionally(VM&);

private:
    JSWebAssemblyCodeBlock(VM&, Ref<Wasm::CodeBlock>&&, const Wasm::ModuleInformation&);
    DECLARE_EXPORT_INFO;
    static constexpr bool needsDestruction = true;
    static void destroy(JSCell*);
    static void visitChildren(JSCell*, SlotVisitor&);

    Ref<Wasm::CodeBlock> m_codeBlock;
    Vector<MacroAssemblerCodeRef<WasmEntryPtrTag>> m_wasmToJSExitStubs;
    Bag<CallLinkInfo> m_callLinkInfos;
    String m_errorMessage;
};

} // namespace JSC

#endif // ENABLE(WEBASSEMBLY)