1 /* 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. Oracle designates this 7 * particular file as subject to the "Classpath" exception as provided 8 * by Oracle in the LICENSE file that accompanied this code. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 */ 24 25 /* 26 * This file is available under and governed by the GNU General Public 27 * License version 2 only, as published by the Free Software Foundation. 28 * However, the following notice accompanied the original version of this 29 * file: 30 * 31 * ASM: a very small and fast Java bytecode manipulation framework 32 * Copyright (c) 2000-2011 INRIA, France Telecom 33 * All rights reserved. 34 * 35 * Redistribution and use in source and binary forms, with or without 36 * modification, are permitted provided that the following conditions 37 * are met: 38 * 1. Redistributions of source code must retain the above copyright 39 * notice, this list of conditions and the following disclaimer. 40 * 2. Redistributions in binary form must reproduce the above copyright 41 * notice, this list of conditions and the following disclaimer in the 42 * documentation and/or other materials provided with the distribution. 43 * 3. Neither the name of the copyright holders nor the names of its 44 * contributors may be used to endorse or promote products derived from 45 * this software without specific prior written permission. 46 * 47 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 48 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 50 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 51 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 52 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 53 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 54 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 55 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 56 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 57 * THE POSSIBILITY OF SUCH DAMAGE. 58 */ 59 package jdk.internal.org.objectweb.asm.tree; 60 61 import java.util.ArrayList; 62 import java.util.List; 63 import java.util.Map; 64 import jdk.internal.org.objectweb.asm.MethodVisitor; 65 import jdk.internal.org.objectweb.asm.Opcodes; 66 67 /** 68 * A node that represents a stack map frame. These nodes are pseudo instruction nodes in order to be 69 * inserted in an instruction list. In fact these nodes must(*) be inserted <i>just before</i> any 70 * instruction node <b>i</b> that follows an unconditionnal branch instruction such as GOTO or 71 * THROW, that is the target of a jump instruction, or that starts an exception handler block. The 72 * stack map frame types must describe the values of the local variables and of the operand stack 73 * elements <i>just before</i> <b>i</b> is executed. <br> 74 * <br> 75 * (*) this is mandatory only for classes whose version is greater than or equal to {@link 76 * Opcodes#V1_6}. 77 * 78 * @author Eric Bruneton 79 */ 80 public class FrameNode extends AbstractInsnNode { 81 82 /** 83 * The type of this frame. Must be {@link Opcodes#F_NEW} for expanded frames, or {@link 84 * Opcodes#F_FULL}, {@link Opcodes#F_APPEND}, {@link Opcodes#F_CHOP}, {@link Opcodes#F_SAME} or 85 * {@link Opcodes#F_APPEND}, {@link Opcodes#F_SAME1} for compressed frames. 86 */ 87 public int type; 88 89 /** 90 * The types of the local variables of this stack map frame. Elements of this list can be Integer, 91 * String or LabelNode objects (for primitive, reference and uninitialized types respectively - 92 * see {@link MethodVisitor}). 93 */ 94 public List<Object> local; 95 96 /** 97 * The types of the operand stack elements of this stack map frame. Elements of this list can be 98 * Integer, String or LabelNode objects (for primitive, reference and uninitialized types 99 * respectively - see {@link MethodVisitor}). 100 */ 101 public List<Object> stack; 102 FrameNode()103 private FrameNode() { 104 super(-1); 105 } 106 107 /** 108 * Constructs a new {@link FrameNode}. 109 * 110 * @param type the type of this frame. Must be {@link Opcodes#F_NEW} for expanded frames, or 111 * {@link Opcodes#F_FULL}, {@link Opcodes#F_APPEND}, {@link Opcodes#F_CHOP}, {@link 112 * Opcodes#F_SAME} or {@link Opcodes#F_APPEND}, {@link Opcodes#F_SAME1} for compressed frames. 113 * @param numLocal number of local variables of this stack map frame. 114 * @param local the types of the local variables of this stack map frame. Elements of this list 115 * can be Integer, String or LabelNode objects (for primitive, reference and uninitialized 116 * types respectively - see {@link MethodVisitor}). 117 * @param numStack number of operand stack elements of this stack map frame. 118 * @param stack the types of the operand stack elements of this stack map frame. Elements of this 119 * list can be Integer, String or LabelNode objects (for primitive, reference and 120 * uninitialized types respectively - see {@link MethodVisitor}). 121 */ FrameNode( final int type, final int numLocal, final Object[] local, final int numStack, final Object[] stack)122 public FrameNode( 123 final int type, 124 final int numLocal, 125 final Object[] local, 126 final int numStack, 127 final Object[] stack) { 128 super(-1); 129 this.type = type; 130 switch (type) { 131 case Opcodes.F_NEW: 132 case Opcodes.F_FULL: 133 this.local = Util.asArrayList(numLocal, local); 134 this.stack = Util.asArrayList(numStack, stack); 135 break; 136 case Opcodes.F_APPEND: 137 this.local = Util.asArrayList(numLocal, local); 138 break; 139 case Opcodes.F_CHOP: 140 this.local = Util.asArrayList(numLocal); 141 break; 142 case Opcodes.F_SAME: 143 break; 144 case Opcodes.F_SAME1: 145 this.stack = Util.asArrayList(1, stack); 146 break; 147 default: 148 throw new IllegalArgumentException(); 149 } 150 } 151 152 @Override getType()153 public int getType() { 154 return FRAME; 155 } 156 157 @Override accept(final MethodVisitor methodVisitor)158 public void accept(final MethodVisitor methodVisitor) { 159 switch (type) { 160 case Opcodes.F_NEW: 161 case Opcodes.F_FULL: 162 methodVisitor.visitFrame(type, local.size(), asArray(local), stack.size(), asArray(stack)); 163 break; 164 case Opcodes.F_APPEND: 165 methodVisitor.visitFrame(type, local.size(), asArray(local), 0, null); 166 break; 167 case Opcodes.F_CHOP: 168 methodVisitor.visitFrame(type, local.size(), null, 0, null); 169 break; 170 case Opcodes.F_SAME: 171 methodVisitor.visitFrame(type, 0, null, 0, null); 172 break; 173 case Opcodes.F_SAME1: 174 methodVisitor.visitFrame(type, 0, null, 1, asArray(stack)); 175 break; 176 default: 177 throw new IllegalArgumentException(); 178 } 179 } 180 181 @Override clone(final Map<LabelNode, LabelNode> clonedLabels)182 public AbstractInsnNode clone(final Map<LabelNode, LabelNode> clonedLabels) { 183 FrameNode clone = new FrameNode(); 184 clone.type = type; 185 if (local != null) { 186 clone.local = new ArrayList<>(); 187 for (int i = 0, n = local.size(); i < n; ++i) { 188 Object localElement = local.get(i); 189 if (localElement instanceof LabelNode) { 190 localElement = clonedLabels.get(localElement); 191 } 192 clone.local.add(localElement); 193 } 194 } 195 if (stack != null) { 196 clone.stack = new ArrayList<>(); 197 for (int i = 0, n = stack.size(); i < n; ++i) { 198 Object stackElement = stack.get(i); 199 if (stackElement instanceof LabelNode) { 200 stackElement = clonedLabels.get(stackElement); 201 } 202 clone.stack.add(stackElement); 203 } 204 } 205 return clone; 206 } 207 asArray(final List<Object> list)208 private static Object[] asArray(final List<Object> list) { 209 Object[] array = new Object[list.size()]; 210 for (int i = 0, n = array.length; i < n; ++i) { 211 Object o = list.get(i); 212 if (o instanceof LabelNode) { 213 o = ((LabelNode) o).getLabel(); 214 } 215 array[i] = o; 216 } 217 return array; 218 } 219 } 220