/*******************************************************************************
 * Copyright IBM Corp. and others 2000
 *
 * This program and the accompanying materials are made available under
 * the terms of the Eclipse Public License 2.0 which accompanies this
 * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
 * or the Apache License, Version 2.0 which accompanies this distribution
 * and is available at https://www.apache.org/licenses/LICENSE-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License, v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception [1] and GNU General Public
 * License, version 2 with the OpenJDK Assembly Exception [2].
 *
 * [1] https://www.gnu.org/software/classpath/license.html
 * [2] https://openjdk.org/legal/assembly-exception.html
 *
 * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0 OR GPL-2.0-only WITH OpenJDK-assembly-exception-1.0
 *******************************************************************************/

#ifndef OMR_REGISTER_PAIR_INCL
#define OMR_REGISTER_PAIR_INCL

/*
 * The following #define and typedef must appear before any #includes in this file
 */
#ifndef OMR_REGISTER_PAIR_CONNECTOR
#define OMR_REGISTER_PAIR_CONNECTOR

namespace OMR {
class RegisterPair;
typedef OMR::RegisterPair RegisterPairConnector;
} // namespace OMR
#endif

#include <stddef.h>
#include <stdint.h>
#include "codegen/Register.hpp"
#include "codegen/RegisterConstants.hpp"

namespace TR {
class CodeGenerator;
class RegisterPair;
} // namespace TR

template<typename QueueKind> class TR_Queue;

namespace OMR {

class OMR_EXTENSIBLE RegisterPair : public TR::Register {
protected:
    RegisterPair()
        : _lowOrder(NULL)
        , _highOrder(NULL)
    {}

    RegisterPair(TR_RegisterKinds rk)
        : TR::Register(rk)
        , _lowOrder(NULL)
        , _highOrder(NULL)
    {}

    RegisterPair(TR::Register *lo, TR::Register *ho)
        : _lowOrder(lo)
        , _highOrder(ho)
    {}

public:
    virtual void block();
    virtual void unblock();
    virtual bool usesRegister(TR::Register *reg);

    virtual TR::Register *getLowOrder();
    virtual TR::Register *getHighOrder();

    TR::Register *setLowOrder(TR::Register *lo, TR::CodeGenerator *cg);
    TR::Register *setHighOrder(TR::Register *ho, TR::CodeGenerator *cg);

    virtual TR::Register *getRegister();
    virtual TR::RegisterPair *getRegisterPair();

private:
    TR::Register *_lowOrder;
    TR::Register *_highOrder;

    TR::RegisterPair *self();
};

} // namespace OMR

#endif
