view src/share/vm/asm/register.hpp @ 452:00b023ae2d78

6722113: CMS: Incorrect overflow handling during precleaning of Reference lists Summary: When we encounter marking stack overflow during precleaning of Reference lists, we were using the overflow list mechanism, which can cause problems on account of mutating the mark word of the header because of conflicts with mutator accesses and updates of that field. Instead we should use the usual mechanism for overflow handling in concurrent phases, namely dirtying of the card on which the overflowed object lies. Since precleaning effectively does a form of discovered list processing, albeit with discovery enabled, we needed to adjust some code to be correct in the face of interleaved processing and discovery. Reviewed-by: apetrusenko, jcoomes
author ysr
date Thu, 20 Nov 2008 12:27:41 -0800
parents a61af66fc99e
children c18cbe5936b8
line wrap: on
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/*
 * Copyright 2000-2002 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

// 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,
    "registers must be different"
  );
}


inline void assert_different_registers(
  AbstractRegister a,
  AbstractRegister b,
  AbstractRegister c
) {
  assert(
    a != b && a != c
           && b != c,
    "registers must be different"
  );
}


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,
    "registers must be different"
  );
}


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,
    "registers must be different"
  );
}


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,
    "registers must be different"
  );
}


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,
    "registers must be different"
  );
}


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,
    "registers must be different"
  );
}