/*

 * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#ifndef SHARE_VM_ASM_REGISTER_HPP

#define SHARE_VM_ASM_REGISTER_HPP

#include "utilities/top.hpp"

// Use AbstractRegister as shortcut

class AbstractRegisterImpl;

typedef AbstractRegisterImpl* AbstractRegister;

// The super class for platform specific registers. Instead of using value objects,

// registers are implemented as pointers. Subclassing is used so all registers can

// use the debugging suport below. No virtual functions are used for efficiency.

// They are canonicalized; i.e., registers are equal if their pointers are equal,

// and vice versa. A concrete implementation may just map the register onto 'this'.

class AbstractRegisterImpl {

 protected:

  int value() const                              { return (int)(intx)this; }

};

//

// Macros for use in defining Register instances.  We'd like to be

// able to simply define const instances of the RegisterImpl* for each

// of the registers needed on a system in a header file.  However many

// compilers don't handle this very well and end up producing a

// private definition in every file which includes the header file.

// Along with the static constructors necessary for initialization it

// can consume a significant amount of space in the result library.

//

// The following macros allow us to declare the instance in a .hpp and

// produce an enumeration value which has the same number.  Then in a

// .cpp the the register instance can be defined using the enumeration

// value.  This avoids the use of static constructors and multiple

// definitions per .cpp.  In addition #defines for the register can be

// produced so that the constant registers can be inlined.  These

// macros should not be used inside other macros, because you may get

// multiple evaluations of the macros which can give bad results.

//

// Here are some example uses and expansions.  Note that the macro

// invocation is terminated with a ;.

//

// CONSTANT_REGISTER_DECLARATION(Register, G0, 0);

//

// extern const Register G0 ;

// enum { G0_RegisterEnumValue = 0 } ;

//

// REGISTER_DECLARATION(Register, Gmethod, G5);

//

// extern const Register Gmethod ;

// enum { Gmethod_RegisterEnumValue = G5_RegisterEnumValue } ;

//

// REGISTER_DEFINITION(Register, G0);

//

// const Register G0 = ( ( Register ) G0_RegisterEnumValue ) ;

//

#define AS_REGISTER(type,name)         ((type)name##_##type##EnumValue)

#define CONSTANT_REGISTER_DECLARATION(type, name, value) \

extern const type name;                                  \

enum { name##_##type##EnumValue = (value) }

#define REGISTER_DECLARATION(type, name, value) \

extern const type name;                         \

enum { name##_##type##EnumValue = value##_##type##EnumValue }

#define REGISTER_DEFINITION(type, name) \

const type name = ((type)name##_##type##EnumValue)

// Debugging support

inline void assert_different_registers(

  AbstractRegister a,

  AbstractRegister b

) {

  assert(

    a != b,

  );

}

inline void assert_different_registers(

  AbstractRegister a,

  AbstractRegister b,

  AbstractRegister c

) {

  assert(

    a != b && a != c

           && b != c,

  );

}

inline void assert_different_registers(

  AbstractRegister a,

  AbstractRegister b,

  AbstractRegister c,

  AbstractRegister d

) {

  assert(

    a != b && a != c && a != d

           && b != c && b != d

                     && c != d,

  );

}

inline void assert_different_registers(

  AbstractRegister a,

  AbstractRegister b,

  AbstractRegister c,

  AbstractRegister d,

  AbstractRegister e

) {

  assert(

    a != b && a != c && a != d && a != e

           && b != c && b != d && b != e

                     && c != d && c != e

                               && d != e,

  );

}

inline void assert_different_registers(

  AbstractRegister a,

  AbstractRegister b,

  AbstractRegister c,

  AbstractRegister d,

  AbstractRegister e,

  AbstractRegister f

) {

  assert(

    a != b && a != c && a != d && a != e && a != f

           && b != c && b != d && b != e && b != f

                     && c != d && c != e && c != f

                               && d != e && d != f

                                         && e != f,

  );

}

inline void assert_different_registers(

  AbstractRegister a,

  AbstractRegister b,

  AbstractRegister c,

  AbstractRegister d,

  AbstractRegister e,

  AbstractRegister f,

  AbstractRegister g

) {

  assert(

    a != b && a != c && a != d && a != e && a != f && a != g

           && b != c && b != d && b != e && b != f && b != g

                     && c != d && c != e && c != f && c != g

                               && d != e && d != f && d != g

                                         && e != f && e != g

                                                   && f != g,

  );

}

inline void assert_different_registers(

  AbstractRegister a,

  AbstractRegister b,

  AbstractRegister c,

  AbstractRegister d,

  AbstractRegister e,

  AbstractRegister f,

  AbstractRegister g,

  AbstractRegister h

) {

  assert(

    a != b && a != c && a != d && a != e && a != f && a != g && a != h

           && b != c && b != d && b != e && b != f && b != g && b != h

                     && c != d && c != e && c != f && c != g && c != h

                               && d != e && d != f && d != g && d != h

                                         && e != f && e != g && e != h

                                                   && f != g && f != h

                                                             && g != h,

  );

}

#endif // SHARE_VM_ASM_REGISTER_HPP