view src/share/vm/ci/ciInstance.hpp @ 1145:e018e6884bd8

6631166: CMS: better heuristics when combatting fragmentation Summary: Autonomic per-worker free block cache sizing, tunable coalition policies, fixes to per-size block statistics, retuned gain and bandwidth of some feedback loop filters to allow quicker reactivity to abrupt changes in ambient demand, and other heuristics to reduce fragmentation of the CMS old gen. Also tightened some assertions, including those related to locking. Reviewed-by: jmasa
author ysr
date Wed, 23 Dec 2009 09:23:54 -0800
parents a61af66fc99e
children c18cbe5936b8
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/*
 * Copyright 1999-2005 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.
 *
 */

// ciInstance
//
// This class represents an instanceOop in the HotSpot virtual
// machine.  This is an oop which corresponds to a non-array
// instance of java.lang.Object.
class ciInstance : public ciObject {
  CI_PACKAGE_ACCESS

protected:
  ciInstance(instanceHandle h_i) : ciObject(h_i) {
    assert(h_i()->is_instance(), "wrong type");
  }

  ciInstance(ciKlass* klass) : ciObject(klass) {}

  instanceOop get_instanceOop() { return (instanceOop)get_oop(); }

  const char* type_string() { return "ciInstance"; }

  void print_impl(outputStream* st);

public:
  // If this object is a java mirror, return the corresponding type.
  // Otherwise, return NULL.
  // (Remember that a java mirror is an instance of java.lang.Class.)
  ciType* java_mirror_type();

  // What kind of ciObject is this?
  bool is_instance()     { return true; }
  bool is_java_object()  { return true; }

  // Constant value of a field.
  ciConstant field_value(ciField* field);

  // Constant value of a field at the specified offset.
  ciConstant field_value_by_offset(int field_offset);
};