proguard.classfile.instruction

Class VariableInstruction

java.lang.Object

proguard.classfile.instruction.Instruction

proguard.classfile.instruction.VariableInstruction

public class VariableInstruction
extends Instruction

This Instruction represents an instruction that refers to a variable on the local variable stack.

Author:

Eric Lafortune

Field Summary

Fields

Modifier and Type	Field and Description
int	constant
int	variableIndex
boolean	wide

Fields inherited from class proguard.classfile.instruction.Instruction

opcode

Constructor Summary

Constructors

Constructor and Description
VariableInstruction() Creates an uninitialized VariableInstruction.
VariableInstruction(boolean wide)
VariableInstruction(byte opcode)
VariableInstruction(byte opcode, int variableIndex)
VariableInstruction(byte opcode, int variableIndex, int constant)

Method Summary

Methods

Modifier and Type	Method and Description
void	accept(Clazz clazz, Method method, CodeAttribute codeAttribute, int offset, InstructionVisitor instructionVisitor) Accepts the given visitor.
byte	canonicalOpcode() Returns the canonical opcode of this instruction, i.e.
VariableInstruction	copy(VariableInstruction variableInstruction) Copies the given instruction into this instruction.
boolean	isLoad() Returns whether this instruction loads the value of a variable.
boolean	isStore() Returns whether this instruction stores the value of a variable.
protected boolean	isWide() Returns whether the instruction is wide, i.e.
int	length(int offset) Returns the length in bytes of the instruction.
protected void	readInfo(byte[] code, int offset) Reads the data following the instruction opcode.
Instruction	shrink() Shrinks this instruction to its shortest possible form.
String	toString()
protected void	writeInfo(byte[] code, int offset) Writes data following the instruction opcode.

Methods inherited from class proguard.classfile.instruction.Instruction

getName, isCategory2, mayThrowExceptions, readByte, readInt, readShort, readSignedByte, readSignedShort, readSignedValue, readValue, stackPopCount, stackPushCount, toString, write, write, writeByte, writeInt, writeShort, writeSignedByte, writeSignedShort, writeSignedValue, writeValue

Methods inherited from class java.lang.Object

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

Field Detail

wide

public boolean wide

variableIndex

public int variableIndex

constant

public int constant

Constructor Detail

VariableInstruction

public VariableInstruction()

Creates an uninitialized VariableInstruction.

VariableInstruction

public VariableInstruction(boolean wide)

VariableInstruction

public VariableInstruction(byte opcode)

VariableInstruction

public VariableInstruction(byte opcode,
                   int variableIndex)

VariableInstruction

public VariableInstruction(byte opcode,
                   int variableIndex,
                   int constant)

Method Detail

copy

public VariableInstruction copy(VariableInstruction variableInstruction)

Copies the given instruction into this instruction.

Parameters:

variableInstruction - the instruction to be copied.

Returns:

this instruction.

isStore

public boolean isStore()

Returns whether this instruction stores the value of a variable. The value is false for the ret instruction, but true for the iinc instruction.

isLoad

public boolean isLoad()

Returns whether this instruction loads the value of a variable. The value is true for the ret instruction and for the iinc instruction.

canonicalOpcode

public byte canonicalOpcode()

Description copied from class: Instruction

Returns the canonical opcode of this instruction, i.e. typically the opcode whose extension has been removed.

Overrides:

canonicalOpcode in class Instruction

shrink

public Instruction shrink()

Description copied from class: Instruction

Shrinks this instruction to its shortest possible form.

Specified by:

shrink in class Instruction

Returns:

this instruction.

isWide

protected boolean isWide()

Description copied from class: Instruction

Returns whether the instruction is wide, i.e. preceded by a wide opcode. With the current specifications, only variable instructions can be wide.

Overrides:

isWide in class Instruction

readInfo

protected void readInfo(byte[] code,
            int offset)

Description copied from class: Instruction

Reads the data following the instruction opcode.

Specified by:

readInfo in class Instruction

writeInfo

protected void writeInfo(byte[] code,
             int offset)

Description copied from class: Instruction

Writes data following the instruction opcode.

Specified by:

writeInfo in class Instruction

length

public int length(int offset)

Description copied from class: Instruction

Returns the length in bytes of the instruction.

Specified by:

length in class Instruction

accept

public void accept(Clazz clazz,
          Method method,
          CodeAttribute codeAttribute,
          int offset,
          InstructionVisitor instructionVisitor)

Description copied from class: Instruction

Accepts the given visitor.

Specified by:

accept in class Instruction

toString

public String toString()

Overrides:

toString in class Object