org.jikesrvm.compilers.opt.ir

Class GCIRMapElement

java.lang.Object

org.jikesrvm.compilers.opt.ir.GCIRMapElement

public final class GCIRMapElement
extends Object

This class holds each element in the GCIRMap

Field Summary

Fields

Modifier and Type	Field and Description
private Instruction	inst The instruction, i.e., GC point
private List<RegSpillListElement>	regSpillList The list of references (either symbolic regs or physical regs & spills)

Constructor Summary

Constructors

Constructor and Description
GCIRMapElement(Instruction inst, List<RegSpillListElement> regSpillList)

Method Summary

Modifier and Type	Method and Description
void	addRegSpillElement(RegSpillListElement e)
int	countNumElements() Counts and returns the number of references for this map
int	countNumRegElements() Counts and returns the number of register elements (not spills) for this entry
int	countNumSpillElements() Counts and returns the number of spill for this entry
GCIRMapElement	createTwin(Instruction inst) Creates a twin entry: required when the same MIR GC point is split into two instructions, both of which are PEIs after register allocation/GCIRMap creation.
void	deleteRegSpillElement(RegSpillListElement e)
Instruction	getInstruction()
List<RegSpillListElement>	regSpillList() returns an enumerator to access the registers/spills for this entry
String	toString() Return a string version of this object

Methods inherited from class java.lang.Object

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

Field Detail

inst

private final Instruction inst

The instruction, i.e., GC point

regSpillList

private final List<RegSpillListElement> regSpillList

The list of references (either symbolic regs or physical regs & spills)

Constructor Detail

GCIRMapElement

public GCIRMapElement(Instruction inst,
                      List<RegSpillListElement> regSpillList)

Parameters:

inst - the instruction of interest

regSpillList - the list of references either symbolic (before regalloc) or physical/spill location (after regalloc)

Method Detail

createTwin

public GCIRMapElement createTwin(Instruction inst)

Creates a twin entry: required when the same MIR GC point is split into two instructions, both of which are PEIs after register allocation/GCIRMap creation.

Parameters:

inst - the instruction which needs a twin element

Returns:

the twin entry

getInstruction

public Instruction getInstruction()

Returns:

the instruction with this entry

regSpillList

public List<RegSpillListElement> regSpillList()

returns an enumerator to access the registers/spills for this entry

Returns:

an enumerator to access the registers/spills for this entry

addRegSpillElement

public void addRegSpillElement(RegSpillListElement e)

deleteRegSpillElement

public void deleteRegSpillElement(RegSpillListElement e)

countNumElements

public int countNumElements()

Counts and returns the number of references for this map

Returns:

the number of references, either regs or spills for this map

countNumRegElements

public int countNumRegElements()

Counts and returns the number of register elements (not spills) for this entry

Returns:

the number of register elements for this entry

countNumSpillElements

public int countNumSpillElements()

Counts and returns the number of spill for this entry

Returns:

the number of spill for this entry

toString

public String toString()

Return a string version of this object

Overrides:

toString in class Object

Returns:

a string version of this object