org.jikesrvm.compilers.opt.regalloc

Class LiveIntervalElement

java.lang.Object

org.jikesrvm.compilers.opt.regalloc.LiveIntervalElement

public final class LiveIntervalElement
extends Object

This class defines a LiveInterval node created by Live Variable analysis and used in Linear Scan.

See Also:

LinearScan

Field Summary

Fields

Modifier and Type	Field and Description
private BasicBlock	bb The basic block holding this live interval element
private Instruction	begin instruction where the live interval begins (null if alive at basic block entry)
private Instruction	end instruction where the live interval ends (null if alive at basic block exit)
(package private) LiveIntervalElement	next LiveIntervalElements are linked in a singly-linked list; this is the next pointer.
private Register	register register that this live interval is for

Constructor Summary

Constructors

Constructor and Description
LiveIntervalElement(Register reg) Use this constructor when the live interval spans a basic block boundary.
LiveIntervalElement(Register reg, Instruction begin, Instruction end) Use this constructur when the live interval is within a basic block

Method Summary

Modifier and Type	Method and Description
BasicBlock	getBasicBlock()
Instruction	getBegin()
Instruction	getEnd()
LiveIntervalElement	getNext()
Register	getRegister()
int	hashCode()
void	setBasicBlock(BasicBlock bb)
void	setBegin(Instruction begin)
void	setNext(LiveIntervalElement Next)
void	setRegister(Register r)
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

register

private Register register

register that this live interval is for

begin

private Instruction begin

instruction where the live interval begins (null if alive at basic block entry)

end

private final Instruction end

instruction where the live interval ends (null if alive at basic block exit)

bb

private BasicBlock bb

The basic block holding this live interval element

next

LiveIntervalElement next

LiveIntervalElements are linked in a singly-linked list; this is the next pointer.

Constructor Detail

LiveIntervalElement

public LiveIntervalElement(Register reg)

Use this constructor when the live interval spans a basic block boundary.

Parameters:

reg - The Register whose live interval we are representing

LiveIntervalElement

public LiveIntervalElement(Register reg,
                           Instruction begin,
                           Instruction end)

Use this constructur when the live interval is within a basic block

Parameters:

reg - the Register whose live interval we are representing

begin - the definition of the register

end - the last use of the register

Method Detail

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

getBegin

public Instruction getBegin()

setBegin

public void setBegin(Instruction begin)

getEnd

public Instruction getEnd()

getRegister

public Register getRegister()

setRegister

public void setRegister(Register r)

getNext

public LiveIntervalElement getNext()

setNext

public void setNext(LiveIntervalElement Next)

getBasicBlock

public BasicBlock getBasicBlock()

setBasicBlock

public void setBasicBlock(BasicBlock bb)