| /* |
| * ProGuard -- shrinking, optimization, obfuscation, and preverification |
| * of Java bytecode. |
| * |
| * Copyright (c) 2002-2011 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.*; |
| import proguard.classfile.attribute.*; |
| import proguard.classfile.attribute.visitor.*; |
| import proguard.classfile.constant.*; |
| import proguard.classfile.constant.visitor.ConstantVisitor; |
| import proguard.classfile.editor.*; |
| import proguard.classfile.instruction.*; |
| import proguard.classfile.instruction.visitor.InstructionVisitor; |
| import proguard.classfile.util.*; |
| import proguard.classfile.visitor.*; |
| import proguard.optimize.info.*; |
| |
| import java.util.*; |
| |
| /** |
| * This AttributeVisitor inlines short methods or methods that are only invoked |
| * once, in the code attributes that it visits. |
| * |
| * @author Eric Lafortune |
| */ |
| public class MethodInliner |
| extends SimplifiedVisitor |
| implements AttributeVisitor, |
| InstructionVisitor, |
| ConstantVisitor, |
| MemberVisitor |
| { |
| private static final int MAXIMUM_INLINED_CODE_LENGTH = Integer.parseInt(System.getProperty("maximum.inlined.code.length", "8")); |
| private static final int MAXIMUM_RESULTING_CODE_LENGTH_JSE = Integer.parseInt(System.getProperty("maximum.resulting.code.length", "7000")); |
| private static final int MAXIMUM_RESULTING_CODE_LENGTH_JME = Integer.parseInt(System.getProperty("maximum.resulting.code.length", "2000")); |
| private static final int MAXIMUM_CODE_EXPANSION = 2; |
| private static final int MAXIMUM_EXTRA_CODE_LENGTH = 128; |
| |
| //* |
| private static final boolean DEBUG = false; |
| /*/ |
| private static boolean DEBUG = true; |
| //*/ |
| |
| |
| private final boolean microEdition; |
| private final boolean allowAccessModification; |
| private final boolean inlineSingleInvocations; |
| private final InstructionVisitor extraInlinedInvocationVisitor; |
| |
| private final CodeAttributeComposer codeAttributeComposer = new CodeAttributeComposer(); |
| private final AccessMethodMarker accessMethodMarker = new AccessMethodMarker(); |
| private final CatchExceptionMarker catchExceptionMarker = new CatchExceptionMarker(); |
| private final StackSizeComputer stackSizeComputer = new StackSizeComputer(); |
| |
| private ProgramClass targetClass; |
| private ProgramMethod targetMethod; |
| private ConstantAdder constantAdder; |
| private ExceptionInfoAdder exceptionInfoAdder; |
| private int estimatedResultingCodeLength; |
| private boolean inlining; |
| private Stack inliningMethods = new Stack(); |
| private boolean emptyInvokingStack; |
| private int uninitializedObjectCount; |
| private int variableOffset; |
| private boolean inlined; |
| private boolean inlinedAny; |
| |
| |
| /** |
| * Creates a new MethodInliner. |
| * @param microEdition indicates whether the resulting code is |
| * targeted at Java Micro Edition. |
| * @param allowAccessModification indicates whether the access modifiers of |
| * classes and class members can be changed |
| * in order to inline methods. |
| * @param inlineSingleInvocations indicates whether the single invocations |
| * should be inlined, or, alternatively, |
| * short methods. |
| */ |
| public MethodInliner(boolean microEdition, |
| boolean allowAccessModification, |
| boolean inlineSingleInvocations) |
| { |
| this(microEdition, |
| allowAccessModification, |
| inlineSingleInvocations, |
| null); |
| } |
| |
| |
| /** |
| * Creates a new MethodInliner. |
| * @param microEdition indicates whether the resulting code is |
| * targeted at Java Micro Edition. |
| * @param allowAccessModification indicates whether the access modifiers of |
| * classes and class members can be changed |
| * in order to inline methods. |
| * @param inlineSingleInvocations indicates whether the single invocations |
| * should be inlined, or, alternatively, |
| * short methods. |
| * @param extraInlinedInvocationVisitor an optional extra visitor for all |
| * inlined invocation instructions. |
| */ |
| public MethodInliner(boolean microEdition, |
| boolean allowAccessModification, |
| boolean inlineSingleInvocations, |
| InstructionVisitor extraInlinedInvocationVisitor) |
| { |
| this.microEdition = microEdition; |
| this.allowAccessModification = allowAccessModification; |
| this.inlineSingleInvocations = inlineSingleInvocations; |
| this.extraInlinedInvocationVisitor = extraInlinedInvocationVisitor; |
| } |
| |
| |
| // Implementations for AttributeVisitor. |
| |
| public void visitAnyAttribute(Clazz clazz, Attribute attribute) {} |
| |
| |
| public void visitCodeAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute) |
| { |
| // TODO: Remove this when the method inliner has stabilized. |
| // Catch any unexpected exceptions from the actual visiting method. |
| try |
| { |
| // Process the code. |
| visitCodeAttribute0(clazz, method, codeAttribute); |
| } |
| catch (RuntimeException ex) |
| { |
| System.err.println("Unexpected error while inlining method:"); |
| System.err.println(" Target class = ["+targetClass.getName()+"]"); |
| System.err.println(" Target method = ["+targetMethod.getName(targetClass)+targetMethod.getDescriptor(targetClass)+"]"); |
| if (inlining) |
| { |
| System.err.println(" Inlined class = ["+clazz.getName()+"]"); |
| System.err.println(" Inlined method = ["+method.getName(clazz)+method.getDescriptor(clazz)+"]"); |
| } |
| System.err.println(" Exception = ["+ex.getClass().getName()+"] ("+ex.getMessage()+")"); |
| System.err.println("Not inlining this method"); |
| |
| if (DEBUG) |
| { |
| targetMethod.accept(targetClass, new ClassPrinter()); |
| if (inlining) |
| { |
| method.accept(clazz, new ClassPrinter()); |
| } |
| |
| throw ex; |
| } |
| } |
| } |
| |
| |
| public void visitCodeAttribute0(Clazz clazz, Method method, CodeAttribute codeAttribute) |
| { |
| if (!inlining) |
| { |
| // codeAttributeComposer.DEBUG = DEBUG = |
| // clazz.getName().equals("abc/Def") && |
| // method.getName(clazz).equals("abc"); |
| |
| targetClass = (ProgramClass)clazz; |
| targetMethod = (ProgramMethod)method; |
| constantAdder = new ConstantAdder(targetClass); |
| exceptionInfoAdder = new ExceptionInfoAdder(targetClass, codeAttributeComposer); |
| estimatedResultingCodeLength = codeAttribute.u4codeLength; |
| inliningMethods.clear(); |
| uninitializedObjectCount = method.getName(clazz).equals(ClassConstants.INTERNAL_METHOD_NAME_INIT) ? 1 : 0; |
| inlinedAny = false; |
| codeAttributeComposer.reset(); |
| stackSizeComputer.visitCodeAttribute(clazz, method, codeAttribute); |
| |
| // Append the body of the code. |
| copyCode(clazz, method, codeAttribute); |
| |
| targetClass = null; |
| targetMethod = null; |
| constantAdder = null; |
| |
| // Update the code attribute if any code has been inlined. |
| if (inlinedAny) |
| { |
| codeAttributeComposer.visitCodeAttribute(clazz, method, codeAttribute); |
| |
| // Update the accessing flags. |
| codeAttribute.instructionsAccept(clazz, method, accessMethodMarker); |
| |
| // Update the exception catching flags. |
| catchExceptionMarker.visitCodeAttribute(clazz, method, codeAttribute); |
| } |
| } |
| |
| // Only inline the method if it is invoked once or if it is short. |
| else if ((inlineSingleInvocations ? |
| MethodInvocationMarker.getInvocationCount(method) == 1 : |
| codeAttribute.u4codeLength <= MAXIMUM_INLINED_CODE_LENGTH) && |
| estimatedResultingCodeLength + codeAttribute.u4codeLength < |
| (microEdition ? |
| MAXIMUM_RESULTING_CODE_LENGTH_JME : |
| MAXIMUM_RESULTING_CODE_LENGTH_JSE)) |
| { |
| if (DEBUG) |
| { |
| System.out.println("MethodInliner: inlining ["+ |
| clazz.getName()+"."+method.getName(clazz)+method.getDescriptor(clazz)+"] in ["+ |
| targetClass.getName()+"."+targetMethod.getName(targetClass)+targetMethod.getDescriptor(targetClass)+"]"); |
| } |
| |
| // Ignore the removal of the original method invocation, |
| // the addition of the parameter setup, and |
| // the modification of a few inlined instructions. |
| estimatedResultingCodeLength += codeAttribute.u4codeLength; |
| |
| // Append instructions to store the parameters. |
| storeParameters(clazz, method); |
| |
| // Inline the body of the code. |
| copyCode(clazz, method, codeAttribute); |
| |
| inlined = true; |
| inlinedAny = true; |
| } |
| } |
| |
| |
| /** |
| * Appends instructions to pop the parameters for the given method, storing |
| * them in new local variables. |
| */ |
| private void storeParameters(Clazz clazz, Method method) |
| { |
| String descriptor = method.getDescriptor(clazz); |
| |
| boolean isStatic = |
| (method.getAccessFlags() & ClassConstants.INTERNAL_ACC_STATIC) != 0; |
| |
| // Count the number of parameters, taking into account their categories. |
| int parameterCount = ClassUtil.internalMethodParameterCount(descriptor); |
| int parameterSize = ClassUtil.internalMethodParameterSize(descriptor); |
| int parameterOffset = isStatic ? 0 : 1; |
| |
| // Store the parameter types. |
| String[] parameterTypes = new String[parameterSize]; |
| |
| InternalTypeEnumeration internalTypeEnumeration = |
| new InternalTypeEnumeration(descriptor); |
| |
| for (int parameterIndex = 0; parameterIndex < parameterSize; parameterIndex++) |
| { |
| String parameterType = internalTypeEnumeration.nextType(); |
| parameterTypes[parameterIndex] = parameterType; |
| if (ClassUtil.internalTypeSize(parameterType) == 2) |
| { |
| parameterIndex++; |
| } |
| } |
| |
| codeAttributeComposer.beginCodeFragment(parameterSize+1); |
| |
| // Go over the parameter types backward, storing the stack entries |
| // in their corresponding variables. |
| for (int parameterIndex = parameterSize-1; parameterIndex >= 0; parameterIndex--) |
| { |
| String parameterType = parameterTypes[parameterIndex]; |
| if (parameterType != null) |
| { |
| byte opcode; |
| switch (parameterType.charAt(0)) |
| { |
| case ClassConstants.INTERNAL_TYPE_BOOLEAN: |
| case ClassConstants.INTERNAL_TYPE_BYTE: |
| case ClassConstants.INTERNAL_TYPE_CHAR: |
| case ClassConstants.INTERNAL_TYPE_SHORT: |
| case ClassConstants.INTERNAL_TYPE_INT: |
| opcode = InstructionConstants.OP_ISTORE; |
| break; |
| |
| case ClassConstants.INTERNAL_TYPE_LONG: |
| opcode = InstructionConstants.OP_LSTORE; |
| break; |
| |
| case ClassConstants.INTERNAL_TYPE_FLOAT: |
| opcode = InstructionConstants.OP_FSTORE; |
| break; |
| |
| case ClassConstants.INTERNAL_TYPE_DOUBLE: |
| opcode = InstructionConstants.OP_DSTORE; |
| break; |
| |
| default: |
| opcode = InstructionConstants.OP_ASTORE; |
| break; |
| } |
| |
| codeAttributeComposer.appendInstruction(parameterSize-parameterIndex-1, |
| new VariableInstruction(opcode, variableOffset + parameterOffset + parameterIndex).shrink()); |
| } |
| } |
| |
| // Put the 'this' reference in variable 0 (plus offset). |
| if (!isStatic) |
| { |
| codeAttributeComposer.appendInstruction(parameterSize, |
| new VariableInstruction(InstructionConstants.OP_ASTORE, variableOffset).shrink()); |
| } |
| |
| codeAttributeComposer.endCodeFragment(); |
| } |
| |
| |
| /** |
| * Appends the code of the given code attribute. |
| */ |
| private void copyCode(Clazz clazz, Method method, CodeAttribute codeAttribute) |
| { |
| // The code may expand, due to expanding constant and variable |
| // instructions. |
| codeAttributeComposer.beginCodeFragment(codeAttribute.u4codeLength); |
| |
| // Copy the instructions. |
| codeAttribute.instructionsAccept(clazz, method, this); |
| |
| // Append a label just after the code. |
| codeAttributeComposer.appendLabel(codeAttribute.u4codeLength); |
| |
| // Copy the exceptions. |
| codeAttribute.exceptionsAccept(clazz, method, exceptionInfoAdder); |
| |
| codeAttributeComposer.endCodeFragment(); |
| } |
| |
| |
| // Implementations for InstructionVisitor. |
| |
| public void visitAnyInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, Instruction instruction) |
| { |
| codeAttributeComposer.appendInstruction(offset, instruction.shrink()); |
| } |
| |
| |
| public void visitSimpleInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, SimpleInstruction simpleInstruction) |
| { |
| // Are we inlining this instruction? |
| if (inlining) |
| { |
| // Replace any return instructions by branches to the end of the code. |
| switch (simpleInstruction.opcode) |
| { |
| case InstructionConstants.OP_IRETURN: |
| case InstructionConstants.OP_LRETURN: |
| case InstructionConstants.OP_FRETURN: |
| case InstructionConstants.OP_DRETURN: |
| case InstructionConstants.OP_ARETURN: |
| case InstructionConstants.OP_RETURN: |
| // Are we not at the last instruction? |
| if (offset < codeAttribute.u4codeLength-1) |
| { |
| // Replace the return instruction by a branch instruction. |
| Instruction branchInstruction = |
| new BranchInstruction(InstructionConstants.OP_GOTO_W, |
| codeAttribute.u4codeLength - offset); |
| |
| codeAttributeComposer.appendInstruction(offset, |
| branchInstruction.shrink()); |
| } |
| else |
| { |
| // Just leave out the instruction, but put in a label, |
| // for the sake of any other branch instructions. |
| codeAttributeComposer.appendLabel(offset); |
| } |
| |
| return; |
| } |
| } |
| |
| codeAttributeComposer.appendInstruction(offset, simpleInstruction.shrink()); |
| } |
| |
| |
| public void visitVariableInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, VariableInstruction variableInstruction) |
| { |
| // Are we inlining this instruction? |
| if (inlining) |
| { |
| // Update the variable index. |
| variableInstruction.variableIndex += variableOffset; |
| } |
| |
| codeAttributeComposer.appendInstruction(offset, variableInstruction.shrink()); |
| } |
| |
| |
| public void visitConstantInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, ConstantInstruction constantInstruction) |
| { |
| // Is it a method invocation? |
| switch (constantInstruction.opcode) |
| { |
| case InstructionConstants.OP_NEW: |
| uninitializedObjectCount++; |
| break; |
| |
| case InstructionConstants.OP_INVOKEVIRTUAL: |
| case InstructionConstants.OP_INVOKESPECIAL: |
| case InstructionConstants.OP_INVOKESTATIC: |
| case InstructionConstants.OP_INVOKEINTERFACE: |
| // See if we can inline it. |
| inlined = false; |
| |
| // Append a label, in case the invocation will be inlined. |
| codeAttributeComposer.appendLabel(offset); |
| |
| emptyInvokingStack = |
| !inlining && |
| stackSizeComputer.isReachable(offset) && |
| stackSizeComputer.getStackSize(offset) == 0; |
| |
| variableOffset += codeAttribute.u2maxLocals; |
| |
| clazz.constantPoolEntryAccept(constantInstruction.constantIndex, this); |
| |
| variableOffset -= codeAttribute.u2maxLocals; |
| |
| // Was the method inlined? |
| if (inlined) |
| { |
| if (extraInlinedInvocationVisitor != null) |
| { |
| extraInlinedInvocationVisitor.visitConstantInstruction(clazz, method, codeAttribute, offset, constantInstruction); |
| } |
| |
| // The invocation itself is no longer necessary. |
| return; |
| } |
| |
| break; |
| } |
| |
| // Are we inlining this instruction? |
| if (inlining) |
| { |
| // Make sure the constant is present in the constant pool of the |
| // target class. |
| constantInstruction.constantIndex = |
| constantAdder.addConstant(clazz, constantInstruction.constantIndex); |
| } |
| |
| codeAttributeComposer.appendInstruction(offset, constantInstruction.shrink()); |
| } |
| |
| |
| // Implementations for ConstantVisitor. |
| |
| public void visitInterfaceMethodrefConstant(Clazz clazz, InterfaceMethodrefConstant interfaceMethodrefConstant) {} |
| |
| |
| public void visitMethodrefConstant(Clazz clazz, MethodrefConstant methodrefConstant) |
| { |
| methodrefConstant.referencedMemberAccept(this); |
| } |
| |
| |
| // Implementations for MemberVisitor. |
| |
| public void visitAnyMember(Clazz Clazz, Member member) {} |
| |
| |
| public void visitProgramMethod(ProgramClass programClass, ProgramMethod programMethod) |
| { |
| int accessFlags = programMethod.getAccessFlags(); |
| |
| if (// Only inline the method if it is private, static, or final. |
| (accessFlags & (ClassConstants.INTERNAL_ACC_PRIVATE | |
| ClassConstants.INTERNAL_ACC_STATIC | |
| ClassConstants.INTERNAL_ACC_FINAL)) != 0 && |
| |
| // Only inline the method if it is not synchronized, etc. |
| (accessFlags & (ClassConstants.INTERNAL_ACC_SYNCHRONIZED | |
| ClassConstants.INTERNAL_ACC_NATIVE | |
| ClassConstants.INTERNAL_ACC_INTERFACE | |
| ClassConstants.INTERNAL_ACC_ABSTRACT)) == 0 && |
| |
| // Don't inline an <init> method, except in an <init> method in the |
| // same class. |
| // (!programMethod.getName(programClass).equals(ClassConstants.INTERNAL_METHOD_NAME_INIT) || |
| // (programClass.equals(targetClass) && |
| // targetMethod.getName(targetClass).equals(ClassConstants.INTERNAL_METHOD_NAME_INIT))) && |
| !programMethod.getName(programClass).equals(ClassConstants.INTERNAL_METHOD_NAME_INIT) && |
| |
| // Don't inline a method into itself. |
| (!programMethod.equals(targetMethod) || |
| !programClass.equals(targetClass)) && |
| |
| // Only inline the method if it isn't recursing. |
| !inliningMethods.contains(programMethod) && |
| |
| // Only inline the method if its target class has at least the |
| // same version number as the source class, in order to avoid |
| // introducing incompatible constructs. |
| targetClass.u4version >= programClass.u4version && |
| |
| // Only inline the method if it doesn't invoke a super method, or if |
| // it is in the same class. |
| (!SuperInvocationMarker.invokesSuperMethods(programMethod) || |
| programClass.equals(targetClass)) && |
| |
| // Only inline the method if it doesn't branch backward while there |
| // are uninitialized objects. |
| (!BackwardBranchMarker.branchesBackward(programMethod) || |
| uninitializedObjectCount == 0) && |
| |
| // Only inline if the code access of the inlined method allows it. |
| (allowAccessModification || |
| ((!AccessMethodMarker.accessesPrivateCode(programMethod) || |
| programClass.equals(targetClass)) && |
| |
| (!AccessMethodMarker.accessesPackageCode(programMethod) || |
| ClassUtil.internalPackageName(programClass.getName()).equals( |
| ClassUtil.internalPackageName(targetClass.getName()))))) && |
| |
| // (!AccessMethodMarker.accessesProtectedCode(programMethod) || |
| // targetClass.extends_(programClass) || |
| // targetClass.implements_(programClass)) || |
| (!AccessMethodMarker.accessesProtectedCode(programMethod) || |
| programClass.equals(targetClass)) && |
| |
| // Only inline the method if it doesn't catch exceptions, or if it |
| // is invoked with an empty stack. |
| (!CatchExceptionMarker.catchesExceptions(programMethod) || |
| emptyInvokingStack) && |
| |
| // Only inline the method if it comes from the a class with at most |
| // a subset of the initialized superclasses. |
| (programClass.equals(targetClass) || |
| initializedSuperClasses(targetClass).containsAll(initializedSuperClasses(programClass)))) |
| { boolean oldInlining = inlining; |
| inlining = true; |
| inliningMethods.push(programMethod); |
| |
| // Inline the method body. |
| programMethod.attributesAccept(programClass, this); |
| |
| // Update the optimization information of the target method. |
| MethodOptimizationInfo info = |
| MethodOptimizationInfo.getMethodOptimizationInfo(targetMethod); |
| if (info != null) |
| { |
| info.merge(MethodOptimizationInfo.getMethodOptimizationInfo(programMethod)); |
| } |
| |
| inlining = oldInlining; |
| inliningMethods.pop(); |
| } |
| else if (programMethod.getName(programClass).equals(ClassConstants.INTERNAL_METHOD_NAME_INIT)) |
| { |
| uninitializedObjectCount--; |
| } |
| } |
| |
| |
| /** |
| * Returns the set of superclasses and interfaces that are initialized. |
| */ |
| private Set initializedSuperClasses(Clazz clazz) |
| { |
| Set set = new HashSet(); |
| |
| // Visit all superclasses and interfaces, collecting the ones that have |
| // static initializers. |
| clazz.hierarchyAccept(true, true, true, false, |
| new StaticInitializerContainingClassFilter( |
| new ClassCollector(set))); |
| |
| return set; |
| } |
| } |
