org.jikesrvm.adaptive.database.callgraph

Class WeightedCallTargets

java.lang.Object

org.jikesrvm.adaptive.database.callgraph.WeightedCallTargets

Direct Known Subclasses:

WeightedCallTargets.MultiTarget, WeightedCallTargets.SingleTarget

public abstract class WeightedCallTargets
extends Object

A collection of weighted call targets. Depending on the size of the callee set, we use different subclasses that optimize the time/space tradeoffs.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	WeightedCallTargets.MultiTarget An implementation for storing a call site distribution that has multiple targets.
private static class	WeightedCallTargets.SingleTarget An implementation for storing a call site distribution that has a single target.
static interface	WeightedCallTargets.Visitor Used by visitTargets

Constructor Summary

Constructors

Constructor and Description
WeightedCallTargets()

Method Summary

Modifier and Type	Method and Description
abstract WeightedCallTargets	augmentCount(RVMMethod target, double amount) Augment the weight associated with the argument method by the argument amount.
static WeightedCallTargets	create(RVMMethod target, double weight)
abstract void	decay(double rate) Decay the weights of all call targets by the specified amount
abstract WeightedCallTargets	filter(RVMMethod goal, boolean isPrecise)
WeightedCallTargets	incrementCount(RVMMethod target) Augment the weight associated with the argument method by 1.
abstract double	totalWeight()
abstract void	visitTargets(WeightedCallTargets.Visitor func) Iterate over all of the targets, evaluating the argument function on each edge.

Methods inherited from class java.lang.Object

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

Constructor Detail

WeightedCallTargets

public WeightedCallTargets()

Method Detail

visitTargets

public abstract void visitTargets(WeightedCallTargets.Visitor func)

Iterate over all of the targets, evaluating the argument function on each edge.

NOTE: We guarantee that the targets will be iterated in monotonically decreasing edge weight. This simplifies the coding of the inlining clients that consume this information.

Parameters:

func - the function to evaluate on each target

incrementCount

public final WeightedCallTargets incrementCount(RVMMethod target)

Augment the weight associated with the argument method by 1.

NOTE: This method may change the representation of the target method. The caller must be sure to update their backing store of WeightedCallTargets accordingly to avoid losing the update.

Parameters:

target - the method whose count is to be incremented

Returns:

the object representing the method's targets

augmentCount

public abstract WeightedCallTargets augmentCount(RVMMethod target,
                                                 double amount)

Augment the weight associated with the argument method by the argument amount. NOTE: This method may change the representation of the target method. The caller must be sure to update their backing store of WeightedCallTargets accordingly to avoid losing the update.

Parameters:

target - the method whose count is to be incremented

amount - amount to increment by

Returns:

the object representing the method's targets

decay

public abstract void decay(double rate)

Decay the weights of all call targets by the specified amount

Parameters:

rate - the value to decay by

totalWeight

public abstract double totalWeight()

Returns:

total weight of all call targets

filter

public abstract WeightedCallTargets filter(RVMMethod goal,
                                           boolean isPrecise)

Parameters:

goal - RVMMethod that is the statically possible target

isPrecise - whether or not goal is a precise target, or should be interpreted as being the root of a virtual method family, any of which are statically possible.

Returns:

the filtered call targets or null if no such target exists

create

public static WeightedCallTargets create(RVMMethod target,
                                         double weight)