001/*
002 *  This file is part of the Jikes RVM project (http://jikesrvm.org).
003 *
004 *  This file is licensed to You under the Eclipse Public License (EPL);
005 *  You may not use this file except in compliance with the License. You
006 *  may obtain a copy of the License at
007 *
008 *      http://www.opensource.org/licenses/eclipse-1.0.php
009 *
010 *  See the COPYRIGHT.txt file distributed with this work for information
011 *  regarding copyright ownership.
012 */
013package org.jikesrvm.runtime;
014
015import static org.jikesrvm.classloader.BytecodeConstants.JBC_invokeinterface;
016import static org.jikesrvm.classloader.BytecodeConstants.JBC_invokespecial;
017import static org.jikesrvm.classloader.BytecodeConstants.JBC_invokestatic;
018import static org.jikesrvm.classloader.BytecodeConstants.JBC_invokevirtual;
019
020import org.jikesrvm.classloader.MethodReference;
021import org.vmmagic.pragma.Uninterruptible;
022
023/**
024 * Place for CompiledMethod.getDynamicLink() to deposit return
025 * information.
026 * <p>
027 * NB this method is called from within GCMapIterator
028 * and has to be uninterruptible (i.e. contain no new bytecodes),
029 * therefore the fields of this class are non-final).
030 */
031@Uninterruptible
032public final class DynamicLink {
033  /** method referenced at a call site */
034  private MethodReference methodRef;
035  /** how method was called at that site */
036  private int bytecode;
037
038  public void set(MethodReference methodRef, int bytecode) {
039    this.methodRef = methodRef;
040    this.bytecode = bytecode;
041  }
042
043  public MethodReference methodRef() {
044    return methodRef;
045  }
046
047  public boolean isInvokedWithImplicitThisParameter() {
048    return bytecode != JBC_invokestatic;
049  }
050
051  boolean isInvokeVirtual() {
052    return bytecode == JBC_invokevirtual;
053  }
054
055  boolean isInvokeSpecial() {
056    return bytecode == JBC_invokespecial;
057  }
058
059  boolean isInvokeStatic() {
060    return bytecode == JBC_invokestatic;
061  }
062
063  boolean isInvokeInterface() {
064    return bytecode == JBC_invokeinterface;
065  }
066}