org.apache.flex.abc.semantics

Class Instruction

java.lang.Object

org.apache.flex.abc.semantics.Instruction

Direct Known Subclasses:

ArbitraryOperandsInstruction, ImmediateOperandInstruction, NoOperandsInstruction, OneOperandInstruction

public abstract class Instruction
extends Object

A representation of an ABC instruction. Note that an instance of Instruction may be shared or reused.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	opcode

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Instruction(int opcode) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
static String	decodeOp(int opcode) Get the symbolic name of an opcode.
static int	decodeOpcodeName(String opcodeName) Decode an opcode name into a numeric constant.
int	getImmediate()
int	getOpcode()
Object	getOperand(int index) Get one of the instruction's non-immediate operands.
int	getOperandCount()
Label	getTarget() Get the target of a branch instruction.
boolean	hasOperands()
boolean	isBranch() Is this a branch instruction?
boolean	isExecutable()
boolean	isImmediate() determine if instruction has immediate operands.
boolean	isReturn() Is this one of the return instructions?
boolean	isTargetableInstruction() Test whether this instructions opcode is targetable
boolean	isTransferOfControl() Is this a transfer of control?
void	setImmediate(int immediate) Set the immediate field of a local register access instruction.
void	setOperands(Object[] operands) Set this Instruction's operands.
void	setTarget(Label target) Set the target of a branch instruction.
void	setTempRegisters(Object[] tempregs) Set the temporary register operands of a hasnext2 instruction.
String	toString()
protected void	unsupported(String diagnostic)

Methods inherited from class java.lang.Object

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

Field Detail

opcode

protected int opcode

See Also:

ABCConstants

Constructor Detail

Instruction

protected Instruction(int opcode)

Constructor.

Method Detail

decodeOpcodeName

public static int decodeOpcodeName(String opcodeName)

Decode an opcode name into a numeric constant.

Parameters:

opcodeName - - the name of the opcode.

Returns:

the opcode's value, or -1 if it's not an opcode.

decodeOp

public static String decodeOp(int opcode)

Get the symbolic name of an opcode.

Returns:

the opcode's symbolic name, or a hex representation if none exists.

getOpcode

public int getOpcode()

Returns:

this instruction's opcode.

See Also:

for opcodes.

isImmediate

public boolean isImmediate()

determine if instruction has immediate operands.

Returns:

true if the instruction has an immediate operand.

getImmediate

public int getImmediate()

Returns:

this Instruction's immediate operand.

getTarget

public Label getTarget()

Get the target of a branch instruction.

Returns:

the target label, or null if not present.

setTarget

public void setTarget(Label target)

Set the target of a branch instruction.

Parameters:

target - - the AET Label this instruction targets.

getOperand

public Object getOperand(int index)

Get one of the instruction's non-immediate operands.

Parameters:

index - - the index of the desired operand.

Returns:

the operand at the given index.

Throws:

IllegalStateException - if the instruction has no operands.

getOperandCount

public int getOperandCount()

Returns:

the number of operands this instruction has.

hasOperands

public boolean hasOperands()

Returns:

true if this instruction has operands (it may have zero operands, but it supports them).

setOperands

public void setOperands(Object[] operands)

Set this Instruction's operands.

isBranch

public boolean isBranch()

Is this a branch instruction?

Returns:

true if the instruction is a branch.

isReturn

public boolean isReturn()

Is this one of the return instructions?

Returns:

true if this instruction is one of the return instructions

isTransferOfControl

public boolean isTransferOfControl()

Is this a transfer of control?

Returns:

true if isBranch() or isReturn() is true, or the opcode is OP_throw.

setImmediate

public void setImmediate(int immediate)

Set the immediate field of a local register access instruction.

setTempRegisters

public void setTempRegisters(Object[] tempregs)

Set the temporary register operands of a hasnext2 instruction.

isExecutable

public boolean isExecutable()

Returns:

true if this instruction is an executable (non-debug) instruction.

isTargetableInstruction

public boolean isTargetableInstruction()

Test whether this instructions opcode is targetable

Returns:

true if the instructions opcode is targetable

toString

public String toString()

Overrides:

toString in class Object

Returns:

a string representation of the opcode.

unsupported

protected void unsupported(String diagnostic)