proguard.optimize.peephole

Class BranchTargetFinder

java.lang.Object

proguard.classfile.util.SimplifiedVisitor

proguard.optimize.peephole.BranchTargetFinder

All Implemented Interfaces:

AttributeVisitor, ExceptionInfoVisitor, ConstantVisitor, InstructionVisitor

public class BranchTargetFinder
extends SimplifiedVisitor
implements AttributeVisitor, InstructionVisitor, ExceptionInfoVisitor, ConstantVisitor

This AttributeVisitor finds all instruction offsets, branch targets, and exception targets in the CodeAttribute objects that it visits.

Author:

Eric Lafortune

Field Summary

Fields

Modifier and Type	Field and Description
static int	NO_SUBROUTINE
static int	NONE
static int	UNKNOWN

Constructor Summary

Constructors

Constructor and Description
BranchTargetFinder()

Method Summary

Methods

Modifier and Type	Method and Description
boolean	containsSubroutines() Returns whether the method contains subroutines, in the CodeAttribute that was visited most recently.
int	creationOffset(int offset) Returns the offset of the 'new' instruction that corresponds to the invocation of the instance initializer at the given offset, or AT_METHOD_ENTRY if the invocation is calling the "super" or "this" initializer method, , or NONE if it is not a 'new' instruction.
int	initializationOffset(int offset) Returns the instruction offset at which the object instance that is created at the given 'new' instruction offset is initialized, or NONE if it is not being created.
boolean	isAfterBranch(int offset) Returns whether the instruction at the given offset comes right after a definite branch instruction in the CodeAttribute that was visited most recently.
boolean	isBranchOrigin(int offset) Returns whether the instruction at the given offset is the origin of a branch instruction in the CodeAttribute that was visited most recently.
boolean	isBranchTarget(int offset) Returns whether the instruction at the given offset is the target of a branch instruction in the CodeAttribute that was visited most recently.
boolean	isExceptionEnd(int offset) Returns whether the instruction at the given offset is the end of an exception try block in the CodeAttribute that was visited most recently.
boolean	isExceptionHandler(int offset) Returns whether the instruction at the given offset is the start of an exception catch block in the CodeAttribute that was visited most recently.
boolean	isExceptionStart(int offset) Returns whether the instruction at the given offset is the start of an exception try block in the CodeAttribute that was visited most recently.
boolean	isInitializer() Returns whether the method is an instance initializer, in the CodeAttribute that was visited most recently.
boolean	isInitializer(int offset) Returns whether the instruction at the given offset is the special invocation of an instance initializer, in the CodeAttribute that was visited most recently.
boolean	isInstruction(int offset) Returns whether there is an instruction at the given offset in the CodeAttribute that was visited most recently.
boolean	isNew(int offset) Returns whether the instruction at the given offset is a 'new' instruction, in the CodeAttribute that was visited most recently.
boolean	isSubroutine(int offset) Returns whether the instruction at the given offset is part of a subroutine in the CodeAttribute that was visited most recently.
boolean	isSubroutineInvocation(int offset) Returns whether the instruction at the given offset is a subroutine invocation in the CodeAttribute that was visited most recently.
boolean	isSubroutineReturning(int offset) Returns whether the subroutine at the given offset is ever returning by means of a regular 'ret' instruction.
boolean	isSubroutineStart(int offset) Returns whether the instruction at the given offset is the start of a subroutine in the CodeAttribute that was visited most recently.
boolean	isTarget(int offset) Returns whether the instruction at the given offset is the target of any kind in the CodeAttribute that was visited most recently.
int	subroutineEnd(int offset) Returns the offset after the subroutine at the given offset, in the CodeAttribute that was visited most recently.
int	subroutineStart(int offset) Returns the start offset of the subroutine at the given offset, in the CodeAttribute that was visited most recently.
int	superInitializationOffset() Returns the instruction offset at which this initializer is calling the "super" or "this" initializer method, or NONE if it is not an initializer.
void	visitAnyAttribute(Clazz clazz, Attribute attribute) Visit any type of attribute.
void	visitAnyConstant(Clazz clazz, Constant constant)
void	visitAnySwitchInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, SwitchInstruction switchInstruction) Visits either type of SwitchInstruction.
void	visitBranchInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, BranchInstruction branchInstruction)
void	visitCodeAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute)
void	visitConstantInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, ConstantInstruction constantInstruction)
void	visitExceptionInfo(Clazz clazz, Method method, CodeAttribute codeAttribute, ExceptionInfo exceptionInfo)
void	visitMethodrefConstant(Clazz clazz, MethodrefConstant methodrefConstant)
void	visitSimpleInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, SimpleInstruction simpleInstruction)
void	visitVariableInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, VariableInstruction variableInstruction)

Methods inherited from class proguard.classfile.util.SimplifiedVisitor

visitAnnotation, visitAnnotation, visitAnnotation, visitAnnotation, visitAnnotation, visitAnnotation, visitAnnotationDefaultAttribute, visitAnnotationElementValue, visitAnyAnnotationsAttribute, visitAnyClass, visitAnyElementValue, visitAnyInstruction, visitAnyMember, visitAnyMethodrefConstant, visitAnyParameterAnnotationsAttribute, visitAnyRefConstant, visitAnyStackMapFrame, visitAnyTargetInfo, visitAnyTypeAnnotationsAttribute, visitAnyVerificationType, visitArrayElementValue, visitBootstrapMethodsAttribute, visitCatchTargetInfo, visitClassConstant, visitClassElementValue, visitConstantElementValue, visitConstantValueAttribute, visitDeprecatedAttribute, visitDeprecatedAttribute, visitDeprecatedAttribute, visitDeprecatedAttribute, visitDoubleConstant, visitDoubleType, visitEmptyTargetInfo, visitEmptyTargetInfo, visitEmptyTargetInfo, visitEnclosingMethodAttribute, visitEnumConstantElementValue, visitExceptionsAttribute, visitFieldrefConstant, visitFloatConstant, visitFloatType, visitFormalParameterTargetInfo, visitFullFrame, visitInnerClassesAttribute, visitIntegerConstant, visitIntegerType, visitInterfaceMethodrefConstant, visitInvokeDynamicConstant, visitLessZeroFrame, visitLibraryClass, visitLibraryField, visitLibraryMember, visitLibraryMethod, visitLineNumberTableAttribute, visitLocalVariableTableAttribute, visitLocalVariableTargetInfo, visitLocalVariableTypeTableAttribute, visitLongConstant, visitLongType, visitLookUpSwitchInstruction, visitMethodHandleConstant, visitMethodParametersAttribute, visitMethodTypeConstant, visitMoreZeroFrame, visitNameAndTypeConstant, visitNullType, visitObjectType, visitOffsetTargetInfo, visitProgramClass, visitProgramField, visitProgramMember, visitProgramMethod, visitRuntimeInvisibleAnnotationsAttribute, visitRuntimeInvisibleAnnotationsAttribute, visitRuntimeInvisibleAnnotationsAttribute, visitRuntimeInvisibleAnnotationsAttribute, visitRuntimeInvisibleParameterAnnotationsAttribute, visitRuntimeInvisibleTypeAnnotationsAttribute, visitRuntimeInvisibleTypeAnnotationsAttribute, visitRuntimeInvisibleTypeAnnotationsAttribute, visitRuntimeInvisibleTypeAnnotationsAttribute, visitRuntimeInvisibleTypeAnnotationsAttribute, visitRuntimeVisibleAnnotationsAttribute, visitRuntimeVisibleAnnotationsAttribute, visitRuntimeVisibleAnnotationsAttribute, visitRuntimeVisibleAnnotationsAttribute, visitRuntimeVisibleParameterAnnotationsAttribute, visitRuntimeVisibleTypeAnnotationsAttribute, visitRuntimeVisibleTypeAnnotationsAttribute, visitRuntimeVisibleTypeAnnotationsAttribute, visitRuntimeVisibleTypeAnnotationsAttribute, visitRuntimeVisibleTypeAnnotationsAttribute, visitSameOneFrame, visitSameZeroFrame, visitSignatureAttribute, visitSignatureAttribute, visitSignatureAttribute, visitSignatureAttribute, visitSourceDirAttribute, visitSourceFileAttribute, visitStackDoubleType, visitStackFloatType, visitStackIntegerType, visitStackLongType, visitStackMapAttribute, visitStackMapTableAttribute, visitStackNullType, visitStackObjectType, visitStackTopType, visitStackUninitializedThisType, visitStackUninitializedType, visitStringConstant, visitSuperTypeTargetInfo, visitSyntheticAttribute, visitSyntheticAttribute, visitSyntheticAttribute, visitSyntheticAttribute, visitTableSwitchInstruction, visitThrowsTargetInfo, visitTopType, visitTypeAnnotation, visitTypeAnnotation, visitTypeAnnotation, visitTypeAnnotation, visitTypeAnnotation, visitTypeAnnotation, visitTypeArgumentTargetInfo, visitTypeParameterBoundTargetInfo, visitTypeParameterBoundTargetInfo, visitTypeParameterBoundTargetInfo, visitTypeParameterBoundTargetInfo, visitTypeParameterTargetInfo, visitTypeParameterTargetInfo, visitTypePathInfo, visitTypePathInfo, visitTypePathInfo, visitTypePathInfo, visitTypePathInfo, visitUninitializedThisType, visitUninitializedType, visitUnknownAttribute, visitUtf8Constant, visitVariablesDoubleType, visitVariablesFloatType, visitVariablesIntegerType, visitVariablesLongType, visitVariablesNullType, visitVariablesObjectType, visitVariablesTopType, visitVariablesUninitializedThisType, visitVariablesUninitializedType

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface proguard.classfile.attribute.visitor.AttributeVisitor

visitAnnotationDefaultAttribute, visitBootstrapMethodsAttribute, visitConstantValueAttribute, visitDeprecatedAttribute, visitDeprecatedAttribute, visitDeprecatedAttribute, visitEnclosingMethodAttribute, visitExceptionsAttribute, visitInnerClassesAttribute, visitLineNumberTableAttribute, visitLocalVariableTableAttribute, visitLocalVariableTypeTableAttribute, visitMethodParametersAttribute, visitRuntimeInvisibleAnnotationsAttribute, visitRuntimeInvisibleAnnotationsAttribute, visitRuntimeInvisibleAnnotationsAttribute, visitRuntimeInvisibleParameterAnnotationsAttribute, visitRuntimeInvisibleTypeAnnotationsAttribute, visitRuntimeInvisibleTypeAnnotationsAttribute, visitRuntimeInvisibleTypeAnnotationsAttribute, visitRuntimeInvisibleTypeAnnotationsAttribute, visitRuntimeVisibleAnnotationsAttribute, visitRuntimeVisibleAnnotationsAttribute, visitRuntimeVisibleAnnotationsAttribute, visitRuntimeVisibleParameterAnnotationsAttribute, visitRuntimeVisibleTypeAnnotationsAttribute, visitRuntimeVisibleTypeAnnotationsAttribute, visitRuntimeVisibleTypeAnnotationsAttribute, visitRuntimeVisibleTypeAnnotationsAttribute, visitSignatureAttribute, visitSignatureAttribute, visitSignatureAttribute, visitSourceDirAttribute, visitSourceFileAttribute, visitStackMapAttribute, visitStackMapTableAttribute, visitSyntheticAttribute, visitSyntheticAttribute, visitSyntheticAttribute, visitUnknownAttribute

Methods inherited from interface proguard.classfile.instruction.visitor.InstructionVisitor

visitLookUpSwitchInstruction, visitTableSwitchInstruction

Methods inherited from interface proguard.classfile.constant.visitor.ConstantVisitor

visitClassConstant, visitDoubleConstant, visitFieldrefConstant, visitFloatConstant, visitIntegerConstant, visitInterfaceMethodrefConstant, visitInvokeDynamicConstant, visitLongConstant, visitMethodHandleConstant, visitMethodTypeConstant, visitNameAndTypeConstant, visitStringConstant, visitUtf8Constant

Field Detail

NONE

public static final int NONE

See Also:

Constant Field Values

UNKNOWN

public static final int UNKNOWN

See Also:

Constant Field Values

NO_SUBROUTINE

public static final int NO_SUBROUTINE

See Also:

Constant Field Values

Constructor Detail

BranchTargetFinder

public BranchTargetFinder()

Method Detail

isInstruction

public boolean isInstruction(int offset)

Returns whether there is an instruction at the given offset in the CodeAttribute that was visited most recently.

isTarget

public boolean isTarget(int offset)

Returns whether the instruction at the given offset is the target of any kind in the CodeAttribute that was visited most recently.

isBranchOrigin

public boolean isBranchOrigin(int offset)

Returns whether the instruction at the given offset is the origin of a branch instruction in the CodeAttribute that was visited most recently.

isBranchTarget

public boolean isBranchTarget(int offset)

Returns whether the instruction at the given offset is the target of a branch instruction in the CodeAttribute that was visited most recently.

isAfterBranch

public boolean isAfterBranch(int offset)

Returns whether the instruction at the given offset comes right after a definite branch instruction in the CodeAttribute that was visited most recently.

isExceptionStart

public boolean isExceptionStart(int offset)

Returns whether the instruction at the given offset is the start of an exception try block in the CodeAttribute that was visited most recently.

isExceptionEnd

public boolean isExceptionEnd(int offset)

Returns whether the instruction at the given offset is the end of an exception try block in the CodeAttribute that was visited most recently.

isExceptionHandler

public boolean isExceptionHandler(int offset)

Returns whether the instruction at the given offset is the start of an exception catch block in the CodeAttribute that was visited most recently.

isSubroutineInvocation

public boolean isSubroutineInvocation(int offset)

Returns whether the instruction at the given offset is a subroutine invocation in the CodeAttribute that was visited most recently.

isSubroutineStart

public boolean isSubroutineStart(int offset)

Returns whether the instruction at the given offset is the start of a subroutine in the CodeAttribute that was visited most recently.

isSubroutine

public boolean isSubroutine(int offset)

Returns whether the instruction at the given offset is part of a subroutine in the CodeAttribute that was visited most recently.

isSubroutineReturning

public boolean isSubroutineReturning(int offset)

Returns whether the subroutine at the given offset is ever returning by means of a regular 'ret' instruction.

subroutineStart

public int subroutineStart(int offset)

Returns the start offset of the subroutine at the given offset, in the CodeAttribute that was visited most recently.

subroutineEnd

public int subroutineEnd(int offset)

Returns the offset after the subroutine at the given offset, in the CodeAttribute that was visited most recently.

isNew

public boolean isNew(int offset)

Returns whether the instruction at the given offset is a 'new' instruction, in the CodeAttribute that was visited most recently.

initializationOffset

public int initializationOffset(int offset)

Returns the instruction offset at which the object instance that is created at the given 'new' instruction offset is initialized, or NONE if it is not being created.

isInitializer

public boolean isInitializer()

Returns whether the method is an instance initializer, in the CodeAttribute that was visited most recently.

superInitializationOffset

public int superInitializationOffset()

Returns the instruction offset at which this initializer is calling the "super" or "this" initializer method, or NONE if it is not an initializer.

isInitializer

public boolean isInitializer(int offset)

Returns whether the instruction at the given offset is the special invocation of an instance initializer, in the CodeAttribute that was visited most recently.

creationOffset

public int creationOffset(int offset)

Returns the offset of the 'new' instruction that corresponds to the invocation of the instance initializer at the given offset, or AT_METHOD_ENTRY if the invocation is calling the "super" or "this" initializer method, , or NONE if it is not a 'new' instruction.

containsSubroutines

public boolean containsSubroutines()

Returns whether the method contains subroutines, in the CodeAttribute that was visited most recently.

visitAnyAttribute

public void visitAnyAttribute(Clazz clazz,
                     Attribute attribute)

Description copied from class: SimplifiedVisitor

Visit any type of attribute.

Overrides:

visitAnyAttribute in class SimplifiedVisitor

visitCodeAttribute

public void visitCodeAttribute(Clazz clazz,
                      Method method,
                      CodeAttribute codeAttribute)

Specified by:

visitCodeAttribute in interface AttributeVisitor

Overrides:

visitCodeAttribute in class SimplifiedVisitor

visitSimpleInstruction

public void visitSimpleInstruction(Clazz clazz,
                          Method method,
                          CodeAttribute codeAttribute,
                          int offset,
                          SimpleInstruction simpleInstruction)

Specified by:

visitSimpleInstruction in interface InstructionVisitor

Overrides:

visitSimpleInstruction in class SimplifiedVisitor

visitConstantInstruction

public void visitConstantInstruction(Clazz clazz,
                            Method method,
                            CodeAttribute codeAttribute,
                            int offset,
                            ConstantInstruction constantInstruction)

Specified by:

visitConstantInstruction in interface InstructionVisitor

Overrides:

visitConstantInstruction in class SimplifiedVisitor

visitVariableInstruction

public void visitVariableInstruction(Clazz clazz,
                            Method method,
                            CodeAttribute codeAttribute,
                            int offset,
                            VariableInstruction variableInstruction)

Specified by:

visitVariableInstruction in interface InstructionVisitor

Overrides:

visitVariableInstruction in class SimplifiedVisitor

visitBranchInstruction

public void visitBranchInstruction(Clazz clazz,
                          Method method,
                          CodeAttribute codeAttribute,
                          int offset,
                          BranchInstruction branchInstruction)

Specified by:

visitBranchInstruction in interface InstructionVisitor

Overrides:

visitBranchInstruction in class SimplifiedVisitor

visitAnySwitchInstruction

public void visitAnySwitchInstruction(Clazz clazz,
                             Method method,
                             CodeAttribute codeAttribute,
                             int offset,
                             SwitchInstruction switchInstruction)

Description copied from class: SimplifiedVisitor

Visits either type of SwitchInstruction.

Overrides:

visitAnySwitchInstruction in class SimplifiedVisitor

visitAnyConstant

public void visitAnyConstant(Clazz clazz,
                    Constant constant)

Overrides:

visitAnyConstant in class SimplifiedVisitor

visitMethodrefConstant

public void visitMethodrefConstant(Clazz clazz,
                          MethodrefConstant methodrefConstant)

Specified by:

visitMethodrefConstant in interface ConstantVisitor

Overrides:

visitMethodrefConstant in class SimplifiedVisitor

visitExceptionInfo

public void visitExceptionInfo(Clazz clazz,
                      Method method,
                      CodeAttribute codeAttribute,
                      ExceptionInfo exceptionInfo)

Specified by:

visitExceptionInfo in interface ExceptionInfoVisitor