view src/share/vm/runtime/fieldDescriptor.hpp @ 2368:dde920245681

6896099: Integrate CMS heap ergo with default heap sizing ergo 6627787: CMS: JVM refuses to start up with -Xms16m -Xmx16m 7000125: CMS: Anti-monotone young gen sizing with respect to maximum whole heap size specification 7027529: CMS: retire CMSUseOldDefaults flag Summary: Simplify CMS heap sizing code, relying on ergonomic initial sizing consistent with other collectors for the most part, controlling only young gen sizing to rein in pause times. Make CMS young gen sizing default statically cpu-dependant. Remove inconsistencies wrt generation sizing and policy code, allowing for the fixing for 6627787 and 7000125. For 7027529, retire the flag CMSUseOldDefaults which had been introduced as a bridge from JDK 5 to JDK 6 a number of years ago. Reviewed-by: brutisso, poonam
author ysr
date Wed, 16 Mar 2011 10:37:08 -0700
parents 3582bf76420e
children 1d1603768966
line wrap: on
line source

/*
 * Copyright (c) 1997, 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_RUNTIME_FIELDDESCRIPTOR_HPP
#define SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP

#include "oops/constantPoolOop.hpp"
#include "oops/klassOop.hpp"
#include "oops/oop.inline.hpp"
#include "oops/symbol.hpp"
#include "runtime/fieldType.hpp"
#include "utilities/accessFlags.hpp"
#include "utilities/constantTag.hpp"

// A fieldDescriptor describes the attributes of a single field (instance or class variable).
// It needs the class constant pool to work (because it only holds indices into the pool
// rather than the actual info).

class fieldDescriptor VALUE_OBJ_CLASS_SPEC {
 private:
  AccessFlags         _access_flags;
  int                 _name_index;
  int                 _signature_index;
  int                 _initial_value_index;
  int                 _offset;
  int                 _generic_signature_index;
  int                 _index; // index into fields() array
  constantPoolHandle  _cp;

 public:
  Symbol* name() const                 { return _cp->symbol_at(_name_index); }
  Symbol* signature() const            { return _cp->symbol_at(_signature_index); }
  klassOop field_holder() const        { return _cp->pool_holder(); }
  constantPoolOop constants() const    { return _cp(); }
  AccessFlags access_flags() const     { return _access_flags; }
  oop loader() const;
  // Offset (in words) of field from start of instanceOop / klassOop
  int offset() const                   { return _offset; }
  Symbol* generic_signature() const    { return (_generic_signature_index > 0 ? _cp->symbol_at(_generic_signature_index) : (Symbol*)NULL); }
  int index() const                    { return _index; }
  typeArrayOop annotations() const;

  // Initial field value
  bool has_initial_value() const          { return _initial_value_index != 0; }
  constantTag initial_value_tag() const;  // The tag will return true on one of is_int(), is_long(), is_single(), is_double()
  jint        int_initial_value() const;
  jlong       long_initial_value() const;
  jfloat      float_initial_value() const;
  jdouble     double_initial_value() const;
  oop         string_initial_value(TRAPS) const;

  // Field signature type
  BasicType field_type() const            { return FieldType::basic_type(signature()); }

  // Access flags
  bool is_public() const                  { return _access_flags.is_public(); }
  bool is_private() const                 { return _access_flags.is_private(); }
  bool is_protected() const               { return _access_flags.is_protected(); }
  bool is_package_private() const         { return !is_public() && !is_private() && !is_protected(); }

  bool is_static() const                  { return _access_flags.is_static(); }
  bool is_final() const                   { return _access_flags.is_final(); }
  bool is_volatile() const                { return _access_flags.is_volatile(); }
  bool is_transient() const               { return _access_flags.is_transient(); }

  bool is_synthetic() const               { return _access_flags.is_synthetic(); }

  bool is_field_access_watched() const    { return _access_flags.is_field_access_watched(); }
  bool is_field_modification_watched() const
                                          { return _access_flags.is_field_modification_watched(); }
  void set_is_field_access_watched(const bool value)
                                          { _access_flags.set_is_field_access_watched(value); }
  void set_is_field_modification_watched(const bool value)
                                          { _access_flags.set_is_field_modification_watched(value); }

  // Initialization
  void initialize(klassOop k, int index);

  // Print
  void print_on(outputStream* st) const         PRODUCT_RETURN;
  void print_on_for(outputStream* st, oop obj)  PRODUCT_RETURN;
};

#endif // SHARE_VM_RUNTIME_FIELDDESCRIPTOR_HPP