text: /*
   * 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.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * 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.
   */
  
  /*
   * This file is available under and governed by the GNU General Public
   * License version 2 only, as published by the Free Software Foundation.
   * However, the following notice accompanied the original version of this
   * file:
   *
   * ASM: a very small and fast Java bytecode manipulation framework
   * Copyright (c) 2000-2011 INRIA, France Telecom
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the name of the copyright holders nor the names of its
   *    contributors may be used to endorse or promote products derived from
   *    this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
   * THE POSSIBILITY OF SUCH DAMAGE.
   */
  package jdk.internal.org.objectweb.asm.tree.analysis;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import jdk.internal.org.objectweb.asm.tree.JumpInsnNode;
  import jdk.internal.org.objectweb.asm.tree.LabelNode;
  
  /**
   * A method subroutine (corresponds to a JSR instruction).
   *
   * @author Eric Bruneton
   */
  class Subroutine {
  
      LabelNode start;
  
      boolean[] access;
  
      List<JumpInsnNode> callers;
  
      private Subroutine() {
      }
  
      Subroutine(final LabelNode start, final int maxLocals,
              final JumpInsnNode caller) {
          this.start = start;
          this.access = new boolean[maxLocals];
          this.callers = new ArrayList<JumpInsnNode>();
          callers.add(caller);
      }
  
      public Subroutine copy() {
          Subroutine result = new Subroutine();
          result.start = start;
          result.access = new boolean[access.length];
          System.arraycopy(access, 0, result.access, 0, access.length);
          result.callers = new ArrayList<JumpInsnNode>(callers);
          return result;
      }
  
      public boolean merge(final Subroutine subroutine) throws AnalyzerException {
          boolean changes = false;
          for (int i = 0; i < access.length; ++i) {
              if (subroutine.access[i] && !access[i]) {
                  access[i] = true;
                  changes = true;
              }
          }
          if (subroutine.start == start) {
              for (int i = 0; i < subroutine.callers.size(); ++i) {
                  JumpInsnNode caller = subroutine.callers.get(i);
                  if (!callers.contains(caller)) {
                      callers.add(caller);
                      changes = true;
                  }
              }
          }
          return changes;
      }
  }
  