| /* |
| * ProGuard -- shrinking, optimization, obfuscation, and preverification |
| * of Java bytecode. |
| * |
| * Copyright (c) 2002-2009 Eric Lafortune (eric@graphics.cornell.edu) |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the Free |
| * Software Foundation; either version 2 of the License, or (at your option) |
| * any later version. |
| * |
| * This program 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 for |
| * more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| package proguard.optimize.peephole; |
| |
| import proguard.classfile.constant.Constant; |
| import proguard.classfile.editor.CodeAttributeEditor; |
| import proguard.classfile.instruction.Instruction; |
| import proguard.classfile.instruction.visitor.*; |
| |
| /** |
| * This InstructionVisitor replaces multiple instruction sequences at once. |
| * |
| * @see InstructionSequenceReplacer |
| * @author Eric Lafortune |
| */ |
| public class InstructionSequencesReplacer |
| extends MultiInstructionVisitor |
| implements InstructionVisitor |
| { |
| private static final int PATTERN_INDEX = 0; |
| private static final int REPLACEMENT_INDEX = 1; |
| |
| |
| /** |
| * Creates a new InstructionSequencesReplacer. |
| * @param patternConstants any constants referenced by the pattern |
| * instruction. |
| * @param instructionSequences the instruction sequences to be replaced, |
| * with subsequently the sequence pair index, |
| * the patten/replacement index (0 or 1), |
| * and the instruction index in the sequence. |
| * @param branchTargetFinder a branch target finder that has been |
| * initialized to indicate branch targets |
| * in the visited code. |
| * @param codeAttributeEditor a code editor that can be used for |
| * accumulating changes to the code. |
| */ |
| public InstructionSequencesReplacer(Constant[] patternConstants, |
| Instruction[][][] instructionSequences, |
| BranchTargetFinder branchTargetFinder, |
| CodeAttributeEditor codeAttributeEditor) |
| { |
| this(patternConstants, |
| instructionSequences, |
| branchTargetFinder, |
| codeAttributeEditor, |
| null); |
| } |
| |
| |
| /** |
| * Creates a new InstructionSequenceReplacer. |
| * @param patternConstants any constants referenced by the pattern |
| * instruction. |
| * @param instructionSequences the instruction sequences to be replaced, |
| * with subsequently the sequence pair index, |
| * the patten/replacement index (0 or 1), |
| * and the instruction index in the sequence. |
| * @param branchTargetFinder a branch target finder that has been |
| * initialized to indicate branch targets |
| * in the visited code. |
| * @param codeAttributeEditor a code editor that can be used for |
| * accumulating changes to the code. |
| * @param extraInstructionVisitor an optional extra visitor for all deleted |
| * load instructions. |
| */ |
| public InstructionSequencesReplacer(Constant[] patternConstants, |
| Instruction[][][] instructionSequences, |
| BranchTargetFinder branchTargetFinder, |
| CodeAttributeEditor codeAttributeEditor, |
| InstructionVisitor extraInstructionVisitor) |
| { |
| super(createInstructionSequenceReplacers(patternConstants, |
| instructionSequences, |
| branchTargetFinder, |
| codeAttributeEditor, |
| extraInstructionVisitor)); |
| } |
| |
| |
| /** |
| * Creates an array of InstructionSequenceReplacer instances. |
| * @param patternConstants any constants referenced by the pattern |
| * instruction. |
| * @param instructionSequences the instruction sequences to be replaced, |
| * with subsequently the sequence pair index, |
| * the from/to index (0 or 1), and the |
| * instruction index in the sequence. |
| * @param branchTargetFinder a branch target finder that has been |
| * initialized to indicate branch targets |
| * in the visited code. |
| * @param codeAttributeEditor a code editor that can be used for |
| * accumulating changes to the code. |
| * @param extraInstructionVisitor an optional extra visitor for all deleted |
| * load instructions. |
| */ |
| private static InstructionVisitor[] createInstructionSequenceReplacers(Constant[] patternConstants, |
| Instruction[][][] instructionSequences, |
| BranchTargetFinder branchTargetFinder, |
| CodeAttributeEditor codeAttributeEditor, |
| InstructionVisitor extraInstructionVisitor) |
| { |
| InstructionVisitor[] instructionSequenceReplacers = |
| new InstructionSequenceReplacer[instructionSequences.length]; |
| |
| for (int index = 0; index < instructionSequenceReplacers.length; index++) |
| { |
| Instruction[][] instructionSequencePair = instructionSequences[index]; |
| instructionSequenceReplacers[index] = |
| new InstructionSequenceReplacer(patternConstants, |
| instructionSequencePair[PATTERN_INDEX], |
| instructionSequencePair[REPLACEMENT_INDEX], |
| branchTargetFinder, |
| codeAttributeEditor, |
| extraInstructionVisitor); |
| } |
| |
| return instructionSequenceReplacers; |
| } |
| } |