org.checkerframework.dataflow.livevariable

Class LiveVarStore

java.lang.Object

org.checkerframework.dataflow.livevariable.LiveVarStore

All Implemented Interfaces:

Store<LiveVarStore>

public class LiveVarStore
extends Object
implements Store<LiveVarStore>

A live variable store contains a set of live variables represented by nodes.

Nested Class Summary

Nested classes/interfaces inherited from interface org.checkerframework.dataflow.analysis.Store

Store.FlowRule, Store.Kind

Constructor Summary

Constructors

Constructor and Description
LiveVarStore() Create a new LiveVarStore.
LiveVarStore(Set<LiveVarValue> liveVarValueSet) Create a new LiveVarStore.

Method Summary

Modifier and Type	Method and Description
void	addUseInExpression(Node expression) Add the information of live variables in an expression to the live variable set.
boolean	canAlias(JavaExpression a, JavaExpression b) Can the objects a and b be aliases? Returns a conservative answer (i.e., returns true if not enough information is available to determine aliasing).
LiveVarStore	copy() Returns an exact copy of this store.
boolean	equals(@Nullable Object obj)
int	hashCode()
void	killLiveVar(LiveVarValue variable) Remove the information of a live variable from the live variable set.
LiveVarStore	leastUpperBound(LiveVarStore other) Compute the least upper bound of two stores.
void	putLiveVar(LiveVarValue variable) Add the information of a live variable into the live variable set.
String	toString()
String	visualize(CFGVisualizer<?,LiveVarStore,?> viz) Delegate visualization responsibility to a visualizer.
LiveVarStore	widenedUpperBound(LiveVarStore previous) It should not be called since it is not used by the backward analysis.

Methods inherited from class java.lang.Object

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

Constructor Detail

LiveVarStore

public LiveVarStore()

Create a new LiveVarStore.

LiveVarStore

public LiveVarStore(Set<LiveVarValue> liveVarValueSet)

Create a new LiveVarStore.

Parameters:

liveVarValueSet - a set of live variable abstract values

Method Detail

putLiveVar

public void putLiveVar(LiveVarValue variable)

Add the information of a live variable into the live variable set.

Parameters:

variable - a live variable

killLiveVar

public void killLiveVar(LiveVarValue variable)

Remove the information of a live variable from the live variable set.

Parameters:

variable - a live variable

addUseInExpression

public void addUseInExpression(Node expression)

Add the information of live variables in an expression to the live variable set.

Parameters:

expression - a node

equals

public boolean equals(@Nullable Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

copy

public LiveVarStore copy()

Description copied from interface: Store

Returns an exact copy of this store.

Specified by:

copy in interface Store<LiveVarStore>

Returns:

an exact copy of this store

leastUpperBound

public LiveVarStore leastUpperBound(LiveVarStore other)

Description copied from interface: Store

Compute the least upper bound of two stores.

Important: This method must fulfill the following contract:

• Does not change this.
• Does not change other.
• Returns a fresh object which is not aliased yet.
• Returns an object of the same (dynamic) type as this, even if the signature is more permissive.
• Is commutative.

Specified by:

leastUpperBound in interface Store<LiveVarStore>

widenedUpperBound

public LiveVarStore widenedUpperBound(LiveVarStore previous)

It should not be called since it is not used by the backward analysis.

Specified by:

widenedUpperBound in interface Store<LiveVarStore>

Parameters:

previous - must be the previous store

canAlias

public boolean canAlias(JavaExpression a,
                        JavaExpression b)

Description copied from interface: Store

Can the objects a and b be aliases? Returns a conservative answer (i.e., returns true if not enough information is available to determine aliasing).

Specified by:

canAlias in interface Store<LiveVarStore>

visualize

public String visualize(CFGVisualizer<?,LiveVarStore,?> viz)

Description copied from interface: Store

Delegate visualization responsibility to a visualizer.

Specified by:

visualize in interface Store<LiveVarStore>

Parameters:

viz - the visualizer to visualize this store

Returns:

the String representation of this store

toString

public String toString()

Overrides:

toString in class Object