proguard.classfile.editor

Class InstructionSequenceReplacer

java.lang.Object

proguard.classfile.editor.InstructionSequenceReplacer

All Implemented Interfaces:

ConstantVisitor, InstructionVisitor

public class InstructionSequenceReplacer
extends java.lang.Object
implements InstructionVisitor, ConstantVisitor

This InstructionVisitor replaces a given pattern instruction sequence by another given replacement instruction sequence. The arguments of the instruction sequences can be wildcards that are matched and replaced.

The class also supports labels (label()) and exception handlers (catch_(int,int,int)) in replacement sequences. They provide local branch offsets inside the replacement sequences (InstructionSequenceReplacer.Label.offset()). For example, creating a replacement sequence with the help of InstructionSequenceBuilder:

     final InstructionSequenceReplacer.Label TRY_START = InstructionSequenceReplacer.label();
     final InstructionSequenceReplacer.Label TRY_END   = InstructionSequenceReplacer.label();
     final InstructionSequenceReplacer.Label CATCH_END = InstructionSequenceReplacer.label();

     final InstructionSequenceReplacer.Label CATCH_EXCEPTION =
         InstructionSequenceReplacer.catch_(TRY_START.offset(),
                                            TRY_END.offset(),
                                            constantPoolEditor.addClassConstant("java/lang/Exception", null));

     Instructions[] replacementInstructions = builder
         .label(TRY_START)
         ......
         .label(TRY_END)
         .goto_(CATCH_END.offset())
         .catch_(CATCH_EXCEPTION)
         ......
         .athrow()
         .label(CATCH_END)
         ......
         .instructions();
 

See Also:

InstructionSequenceMatcher

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	InstructionSequenceReplacer.Label This pseudo-instruction represents a label that marks an instruction offset, for use in the context of the sequence replacer only.

Field Summary

Fields

Modifier and Type	Field and Description
static int	A
static int	B
static int	BOOLEAN_A_STRING
static int	BOOLEAN_B_STRING
static int	C
static int	CHAR_A_STRING
static int	CHAR_B_STRING
static int	CLASS_A_NAME
static int	CLASS_A_SIMPLE_NAME
static int	D
static int	DOUBLE_A_STRING
static int	DOUBLE_B_STRING
static int	E
static int	F
static int	FLOAT_A_STRING
static int	FLOAT_B_STRING
static int	G
static int	H
static int	I
static int	INT_A_STRING
static int	INT_B_STRING
static int	J
static int	K
static int	L
static int	LONG_A_STRING
static int	LONG_B_STRING
static int	M
static int	N
static int	O
static int	P
static int	Q
static int	R
static int	STRING_A_LENGTH
static int	STRING_A_STRING
static int	STRING_B_STRING
static int	X
static int	Y
static int	Z

Constructor Summary

Constructors

Modifier	Constructor and Description
	InstructionSequenceReplacer(Constant[] patternConstants, Instruction[] patternInstructions, Constant[] replacementConstants, Instruction[] replacementInstructions, BranchTargetFinder branchTargetFinder, CodeAttributeEditor codeAttributeEditor) Creates a new InstructionSequenceReplacer.
	InstructionSequenceReplacer(Constant[] patternConstants, Instruction[] patternInstructions, Constant[] replacementConstants, Instruction[] replacementInstructions, BranchTargetFinder branchTargetFinder, CodeAttributeEditor codeAttributeEditor, InstructionVisitor extraInstructionVisitor) Creates a new InstructionSequenceReplacer.
protected	InstructionSequenceReplacer(InstructionSequenceMatcher instructionSequenceMatcher, Constant[] replacementConstants, Instruction[] replacementInstructions, BranchTargetFinder branchTargetFinder, CodeAttributeEditor codeAttributeEditor, InstructionVisitor extraInstructionVisitor) Creates a new InstructionSequenceReplacer.
	InstructionSequenceReplacer(InstructionSequenceMatcher instructionSequenceMatcher, Constant[] patternConstants, Instruction[] patternInstructions, Constant[] replacementConstants, Instruction[] replacementInstructions, BranchTargetFinder branchTargetFinder, CodeAttributeEditor codeAttributeEditor, InstructionVisitor extraInstructionVisitor) Deprecated. Use InstructionSequenceReplacer(InstructionSequenceMatcher, Constant[], Instruction[], BranchTargetFinder, CodeAttributeEditor, InstructionVisitor) instead.

Method Summary

Modifier and Type	Method and Description
static InstructionSequenceReplacer.Label	catch_(int startOffset, int endOffset, int catchType) Creates a new catch instance that can be used as a pseudo-instruction to mark the start of an exception handler.
protected InstructionSequenceMatcher	getInstructionSequenceMatcher()
static InstructionSequenceReplacer.Label	label() Creates a new label that can be used as a pseudo-instruction to mark a local offset.
protected int	matchedArgument(Clazz clazz, int argument) Returns the matched argument for the given pattern argument.
protected int	matchedArgument(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, int argument) Returns the matched argument for the given pattern argument.
protected int	matchedArgument(int argument)
protected int	matchedBranchOffset(int offset, int branchOffset) Returns the value of the specified matched branch offset.
protected Constant	matchedConstant(ProgramClass programClass, int argument)
protected int	matchedConstantIndex(ProgramClass programClass, int constantIndex) Returns the matched or newly created constant index for the given pattern constant index.
protected int[]	matchedJumpOffsets(int offset, int[] jumpOffsets) Returns the values of the specified matched jump offsets.
void	visitAnyInstruction(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, Instruction instruction) Visits any Instruction instance.
protected boolean	wasConstant(int argument)

Methods inherited from class java.lang.Object

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

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

visitAnySwitchInstruction, visitBranchInstruction, visitConstantInstruction, visitLookUpSwitchInstruction, visitSimpleInstruction, visitTableSwitchInstruction, visitVariableInstruction

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

visitAnyConstant, visitAnyMethodrefConstant, visitAnyRefConstant, visitClassConstant, visitDoubleConstant, visitDynamicConstant, visitFieldrefConstant, visitFloatConstant, visitIntegerConstant, visitInterfaceMethodrefConstant, visitInvokeDynamicConstant, visitLongConstant, visitMethodHandleConstant, visitMethodrefConstant, visitMethodTypeConstant, visitModuleConstant, visitNameAndTypeConstant, visitPackageConstant, visitPrimitiveArrayConstant, visitStringConstant, visitUtf8Constant

Field Detail

X

public static final int X

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Constant Field Values

Y

public static final int Y

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Constant Field Values

Z

public static final int Z

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Constant Field Values

A

public static final int A

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Constant Field Values

B

public static final int B

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Constant Field Values

C

public static final int C

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Constant Field Values

D

public static final int D

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Constant Field Values

E

public static final int E

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Constant Field Values

F

public static final int F

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Constant Field Values

G

public static final int G

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Constant Field Values

H

public static final int H

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Constant Field Values

I

public static final int I

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Constant Field Values

J

public static final int J

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Constant Field Values

K

public static final int K

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Constant Field Values

L

public static final int L

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Constant Field Values

M

public static final int M

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Constant Field Values

N

public static final int N

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Constant Field Values

O

public static final int O

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Constant Field Values

P

public static final int P

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Constant Field Values

Q

public static final int Q

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Constant Field Values

R

public static final int R

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Constant Field Values

STRING_A_LENGTH

public static final int STRING_A_LENGTH

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Constant Field Values

CLASS_A_NAME

public static final int CLASS_A_NAME

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Constant Field Values

CLASS_A_SIMPLE_NAME

public static final int CLASS_A_SIMPLE_NAME

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Constant Field Values

BOOLEAN_A_STRING

public static final int BOOLEAN_A_STRING

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Constant Field Values

CHAR_A_STRING

public static final int CHAR_A_STRING

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Constant Field Values

INT_A_STRING

public static final int INT_A_STRING

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Constant Field Values

LONG_A_STRING

public static final int LONG_A_STRING

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Constant Field Values

FLOAT_A_STRING

public static final int FLOAT_A_STRING

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Constant Field Values

DOUBLE_A_STRING

public static final int DOUBLE_A_STRING

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Constant Field Values

STRING_A_STRING

public static final int STRING_A_STRING

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Constant Field Values

BOOLEAN_B_STRING

public static final int BOOLEAN_B_STRING

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Constant Field Values

CHAR_B_STRING

public static final int CHAR_B_STRING

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Constant Field Values

INT_B_STRING

public static final int INT_B_STRING

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Constant Field Values

LONG_B_STRING

public static final int LONG_B_STRING

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Constant Field Values

FLOAT_B_STRING

public static final int FLOAT_B_STRING

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Constant Field Values

DOUBLE_B_STRING

public static final int DOUBLE_B_STRING

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Constant Field Values

STRING_B_STRING

public static final int STRING_B_STRING

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Constant Field Values

Constructor Detail

InstructionSequenceReplacer

public InstructionSequenceReplacer(Constant[] patternConstants,
                                   Instruction[] patternInstructions,
                                   Constant[] replacementConstants,
                                   Instruction[] replacementInstructions,
                                   BranchTargetFinder branchTargetFinder,
                                   CodeAttributeEditor codeAttributeEditor)

Creates a new InstructionSequenceReplacer.

Parameters:

patternConstants - any constants referenced by the pattern instructions.

patternInstructions - the pattern instruction sequence.

replacementConstants - any constants referenced by the replacement instructions.

replacementInstructions - the replacement instruction sequence.

branchTargetFinder - a branch target finder that has been initialized to indicate branch targets in the visited code.

codeAttributeEditor - a code editor that can be used for accumulating changes to the code.

InstructionSequenceReplacer

public InstructionSequenceReplacer(Constant[] patternConstants,
                                   Instruction[] patternInstructions,
                                   Constant[] replacementConstants,
                                   Instruction[] replacementInstructions,
                                   BranchTargetFinder branchTargetFinder,
                                   CodeAttributeEditor codeAttributeEditor,
                                   InstructionVisitor extraInstructionVisitor)

Creates a new InstructionSequenceReplacer.

Parameters:

patternConstants - any constants referenced by the pattern instructions.

patternInstructions - the pattern instruction sequence.

replacementConstants - any constants referenced by the replacement instructions.

replacementInstructions - the replacement instruction sequence.

branchTargetFinder - a branch target finder that has been initialized to indicate branch targets in the visited code.

codeAttributeEditor - a code editor that can be used for accumulating changes to the code.

extraInstructionVisitor - an optional extra visitor for all deleted load instructions.

InstructionSequenceReplacer

@Deprecated
public InstructionSequenceReplacer(InstructionSequenceMatcher instructionSequenceMatcher,
                                               Constant[] patternConstants,
                                               Instruction[] patternInstructions,
                                               Constant[] replacementConstants,
                                               Instruction[] replacementInstructions,
                                               BranchTargetFinder branchTargetFinder,
                                               CodeAttributeEditor codeAttributeEditor,
                                               InstructionVisitor extraInstructionVisitor)

Deprecated. Use InstructionSequenceReplacer(InstructionSequenceMatcher, Constant[], Instruction[], BranchTargetFinder, CodeAttributeEditor, InstructionVisitor) instead.

Creates a new InstructionSequenceReplacer.

Parameters:

instructionSequenceMatcher - a suitable instruction sequence matcher.

patternConstants - any constants referenced by the pattern instructions.

patternInstructions - the pattern instruction sequence.

replacementConstants - any constants referenced by the replacement instructions.

replacementInstructions - the replacement instruction sequence.

branchTargetFinder - a branch target finder that has been initialized to indicate branch targets in the visited code.

codeAttributeEditor - a code editor that can be used for accumulating changes to the code.

extraInstructionVisitor - an optional extra visitor for all deleted load instructions.

InstructionSequenceReplacer

protected InstructionSequenceReplacer(InstructionSequenceMatcher instructionSequenceMatcher,
                                      Constant[] replacementConstants,
                                      Instruction[] replacementInstructions,
                                      BranchTargetFinder branchTargetFinder,
                                      CodeAttributeEditor codeAttributeEditor,
                                      InstructionVisitor extraInstructionVisitor)

Creates a new InstructionSequenceReplacer.

Parameters:

instructionSequenceMatcher - a suitable instruction sequence matcher.

replacementConstants - any constants referenced by the replacement instructions.

replacementInstructions - the replacement instruction sequence.

branchTargetFinder - a branch target finder that has been initialized to indicate branch targets in the visited code.

codeAttributeEditor - a code editor that can be used for accumulating changes to the code.

extraInstructionVisitor - an optional extra visitor for all deleted load instructions.

Method Detail

visitAnyInstruction

public void visitAnyInstruction(Clazz clazz,
                                Method method,
                                CodeAttribute codeAttribute,
                                int offset,
                                Instruction instruction)

Description copied from interface: InstructionVisitor

Visits any Instruction instance. The more specific default implementations of this interface delegate to this method.

Specified by:

visitAnyInstruction in interface InstructionVisitor

matchedArgument

protected int matchedArgument(Clazz clazz,
                              Method method,
                              CodeAttribute codeAttribute,
                              int offset,
                              int argument)

Returns the matched argument for the given pattern argument.

matchedArgument

protected int matchedArgument(Clazz clazz,
                              int argument)

Returns the matched argument for the given pattern argument.

matchedConstantIndex

protected int matchedConstantIndex(ProgramClass programClass,
                                   int constantIndex)

Returns the matched or newly created constant index for the given pattern constant index.

matchedBranchOffset

protected int matchedBranchOffset(int offset,
                                  int branchOffset)

Returns the value of the specified matched branch offset.

matchedJumpOffsets

protected int[] matchedJumpOffsets(int offset,
                                   int[] jumpOffsets)

Returns the values of the specified matched jump offsets.

getInstructionSequenceMatcher

protected InstructionSequenceMatcher getInstructionSequenceMatcher()

wasConstant

protected boolean wasConstant(int argument)

matchedConstant

protected Constant matchedConstant(ProgramClass programClass,
                                   int argument)

matchedArgument

protected int matchedArgument(int argument)

label

public static InstructionSequenceReplacer.Label label()

Creates a new label that can be used as a pseudo-instruction to mark a local offset. Its offset can be used as a branch target in replacement instructions (InstructionSequenceReplacer.Label.offset()).

catch_

public static InstructionSequenceReplacer.Label catch_(int startOffset,
                                                       int endOffset,
                                                       int catchType)

Creates a new catch instance that can be used as a pseudo-instruction to mark the start of an exception handler. Its offset can be used as a branch target in replacement instructions (InstructionSequenceReplacer.Label.offset()).