// SPDX-License-Identifier: Apache-2.0

// SPDX-FileCopyrightText: Copyright The WasmEdge Authors

//===-- wasmedge/runtime/instance/global.h - Global Instance definition ---===//

//

// Part of the WasmEdge Project.

//

//===----------------------------------------------------------------------===//

///

/// \file

/// This file contains the global instance definition in store manager.

///

//===----------------------------------------------------------------------===//

#pragma once

#include "ast/type.h"

namespace WasmEdge {

namespace Runtime {

namespace Instance {

class ModuleInstance;

class GlobalInstance {

public:

  GlobalInstance() = delete;

  GlobalInstance(const AST::GlobalType &GType,

                 ValVariant Val = uint128_t(0U)) noexcept

      : GlobType(GType), Value(Val) {

    assuming(GType.getValType().isNumType() ||

             GType.getValType().isNullableRefType() ||

             !Val.get<RefVariant>().isNull());

  }

  /// Constructor for a global instance defined by a module.

  GlobalInstance(const ModuleInstance *Mod, const AST::GlobalType &GType,

                 ValVariant Val) noexcept

      : GlobalInstance(GType, Val) {

    ModInst = Mod;

  }

  /// Getter for the defining module instance, if any.

  const ModuleInstance *getModule() const noexcept { return ModInst; }

  /// Getter for global type.

  const AST::GlobalType &getGlobalType() const noexcept { return GlobType; }

  /// Getter for value.

  const ValVariant &getValue() const noexcept { return Value; }

  ValVariant &getValue() noexcept { return Value; }

  /// Setter for value.

  void setValue(const ValVariant &Val) noexcept { Value = Val; }

private:

  /// \name Data of global instance.

  /// @{

  const ModuleInstance *ModInst = nullptr;

  AST::GlobalType GlobType;

  alignas(16) ValVariant Value;

  /// @}

};

} // namespace Instance

} // namespace Runtime

} // namespace WasmEdge