1b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato/* 2b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * ProGuard -- shrinking, optimization, obfuscation, and preverification 3b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * of Java bytecode. 4b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 5b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang * Copyright (c) 2002-2013 Eric Lafortune (eric@graphics.cornell.edu) 6b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 7b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * This program is free software; you can redistribute it and/or modify it 8b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * under the terms of the GNU General Public License as published by the Free 9b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * Software Foundation; either version 2 of the License, or (at your option) 10b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * any later version. 11b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 12b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * This program is distributed in the hope that it will be useful, but WITHOUT 13b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 14b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 15b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * more details. 16b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 17b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * You should have received a copy of the GNU General Public License along 18b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * with this program; if not, write to the Free Software Foundation, Inc., 19b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato */ 21b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratopackage proguard.classfile.editor; 22b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 23b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.*; 24b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.attribute.*; 25b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.attribute.visitor.AttributeVisitor; 26b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.instruction.*; 27b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.instruction.visitor.InstructionVisitor; 28b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimport proguard.classfile.util.*; 29b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 30b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato/** 31b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * This AttributeVisitor computes and updates the maximum local variable frame 32b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang * size of the code attributes that it visits. It also cleans up the local 33b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang * variable tables. 34b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * 35b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato * @author Eric Lafortune 36b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato */ 37b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratopublic class VariableSizeUpdater 38b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoextends SimplifiedVisitor 39b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onoratoimplements AttributeVisitor, 40b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato InstructionVisitor 41b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato{ 42b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato //* 43b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato private static final boolean DEBUG = false; 44b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato /*/ 45b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato private static boolean DEBUG = true; 46b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato //*/ 47b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 48b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 49b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang private VariableCleaner variableCleaner = new VariableCleaner(); 50b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang 51b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang 52b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Implementations for AttributeVisitor. 53b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 54b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitAnyAttribute(Clazz clazz, Attribute attribute) {} 55b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 56b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 57b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitCodeAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute) 58b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 59b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato// DEBUG = 60b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato// clazz.getName().equals("abc/Def") && 61b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato// method.getName(clazz).equals("abc"); 62b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 63b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // The minimum variable size is determined by the arguments. 64b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato codeAttribute.u2maxLocals = 65b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato ClassUtil.internalMethodParameterSize(method.getDescriptor(clazz), 66b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato method.getAccessFlags()); 67b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 68b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (DEBUG) 69b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 70b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato System.out.println("VariableSizeUpdater: "+clazz.getName()+"."+method.getName(clazz)+method.getDescriptor(clazz)); 71b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato System.out.println(" Max locals: "+codeAttribute.u2maxLocals+" <- parameters"); 72b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 73b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 74b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Go over all instructions. 75b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato codeAttribute.instructionsAccept(clazz, method, this); 76b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang 77b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang // Remove the unused variables of the attributes. 78b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang variableCleaner.visitCodeAttribute(clazz, method, codeAttribute); 79b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 80b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 81b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 82b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato // Implementations for InstructionVisitor. 83b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 84b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitAnyInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, Instruction instruction) {} 85b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 86b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 87b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato public void visitVariableInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, VariableInstruction variableInstruction) 88b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 89b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato int variableSize = variableInstruction.variableIndex + 1; 90b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (variableInstruction.isCategory2()) 91b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 92b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato variableSize++; 93b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 94b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 95b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (codeAttribute.u2maxLocals < variableSize) 96b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 97b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato codeAttribute.u2maxLocals = variableSize; 98b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato 99b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato if (DEBUG) 100b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato { 101b9cc48a43ed984587c939d02fba5316bf5c0df6eYing Wang System.out.println(" Max locals: "+codeAttribute.u2maxLocals+" <- "+variableInstruction.toString(offset)); 102b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 103b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 104b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato } 105b72c5c2e5482cf10117b2b25f642f7616b2326c3Joe Onorato} 106