org.jikesrvm.compilers.opt.regalloc

Class SpillLocationManager

java.lang.Object

org.jikesrvm.compilers.opt.regalloc.SpillLocationManager

class SpillLocationManager
extends Object

The following class manages allocation and reuse of spill locations.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) HashSet<SpillLocationInterval>	freeIntervals Set of spill locations which were previously allocated, but may be free since the assigned register is no longer live.
private IR	ir The governing IR

Constructor Summary

Constructors

Constructor and Description
SpillLocationManager(IR ir)

Method Summary

Modifier and Type	Method and Description
(package private) SpillLocationInterval	findOrCreateSpillLocation(CompoundInterval ci)
(package private) void	freeInterval(SpillLocationInterval i) Records that a particular interval is potentially available for reuse.
(package private) SpillLocationInterval	getSpillPreference(CompoundInterval ci, int spillSize, int type) Given the current state of the register allocator, compute the available spill location to which ci has the highest preference.

Methods inherited from class java.lang.Object

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

Field Detail

ir

private final IR ir

The governing IR

freeIntervals

final HashSet<SpillLocationInterval> freeIntervals

Set of spill locations which were previously allocated, but may be free since the assigned register is no longer live.

Constructor Detail

SpillLocationManager

SpillLocationManager(IR ir)

Method Detail

findOrCreateSpillLocation

SpillLocationInterval findOrCreateSpillLocation(CompoundInterval ci)

Parameters:

ci - a compound interval that we want to spill

Returns:

a spill location that is valid to hold the contents of the compound interval

freeInterval

void freeInterval(SpillLocationInterval i)

Records that a particular interval is potentially available for reuse.

Parameters:

i - the interval to free

getSpillPreference

SpillLocationInterval getSpillPreference(CompoundInterval ci,
                                         int spillSize,
                                         int type)

Given the current state of the register allocator, compute the available spill location to which ci has the highest preference.

Parameters:

ci - the interval to spill

spillSize - the size of spill location needed

type - the physical register's type

Returns:

the interval to spill to. null if no preference found.