JDK14/Java14源码在线阅读

/*
 * Copyright (c) 2014, 2019, 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_SERVICES_NMTCOMMON_HPP
#define SHARE_SERVICES_NMTCOMMON_HPP

#include "memory/allocation.hpp"
#include "utilities/align.hpp"
#include "utilities/globalDefinitions.hpp"

#define CALC_OBJ_SIZE_IN_TYPE(obj, type) (align_up_(sizeof(obj), sizeof(type))/sizeof(type))

// Native memory tracking level
enum NMT_TrackingLevel {
  NMT_unknown = 0xFF,
  NMT_off     = 0x00,
  NMT_minimal = 0x01,
  NMT_summary = 0x02,
  NMT_detail  = 0x03
};

// Number of stack frames to capture. This is a
// build time decision.
const int NMT_TrackingStackDepth = 4;

// A few common utilities for native memory tracking
class NMTUtil : AllStatic {
 public:
  // Map memory type to index
  static inline int flag_to_index(MEMFLAGS flag) {
    const int index = flag & 0xff;
    assert(index >= 0 && index < (int)mt_number_of_types, "Index out of bounds");
    return index;
  }

  // Map memory type to human readable name
  static const char* flag_to_name(MEMFLAGS flag) {
    return _memory_type_names[flag_to_index(flag)];
  }

  // Map an index to memory type
  static MEMFLAGS index_to_flag(int index) {
    assert(index >= 0 && index < (int) mt_number_of_types, "Index out of bounds");
    return (MEMFLAGS)index;
  }

  // Memory size scale
  static const char* scale_name(size_t scale);
  static size_t scale_from_name(const char* scale);


/**代码未完, 请加载全部代码(NowJava.com).**/