Package it.unive.lisa.program.cfg.statement

Class VariableRef

java.lang.Object

it.unive.lisa.program.cfg.statement.Statement

it.unive.lisa.program.cfg.statement.Expression

it.unive.lisa.program.cfg.statement.VariableRef

All Implemented Interfaces:

ProgramPoint, CodeElement, CodeNode<CFG,Statement,Edge>, Node<CFG,Statement,Edge>, java.lang.Comparable<Statement>

public class VariableRef
extends Expression

A reference to a variable of the current CFG, identified by its name.

Field Summary

Fields inherited from class it.unive.lisa.program.cfg.statement.Statement

offset

Constructor Summary

Constructors

Constructor	Description
VariableRef(CFG cfg, CodeLocation location, java.lang.String name)	Builds the untyped variable reference, identified by its name.
VariableRef(CFG cfg, CodeLocation location, java.lang.String name, Type type)	Builds the variable reference, identified by its name, happening at the given location in the program.

Method Summary

Modifier and Type	Method	Description
<V> boolean	accept(GraphVisitor<CFG,Statement,Edge,V> visitor, V tool)	Accepts the given GraphVisitor.
boolean	equals(java.lang.Object obj)
<A extends AbstractState<A>> AnalysisState<A>	forwardSemantics(AnalysisState<A> entryState, InterproceduralAnalysis<A> interprocedural, StatementStore<A> expressions)	Computes the forward semantics of the statement, expressing how semantic information is transformed by the execution of this statement.
Annotations	getAnnotations()	Yields the annotations of this variable, retrieved from the variable table of the cfg this variable belongs to.
java.lang.String	getName()	Yields the name of this variable.
Variable	getVariable()	Yields a Variable representing the referenced variable.
int	hashCode()
int	setOffset(int offset)	Sets the offset of this node to the given value, and then proceeds by setting the one of its nested nodes (if any) to subsequent values.
java.lang.String	toString()

Methods inherited from class it.unive.lisa.program.cfg.statement.Expression

getMetaVariables, getParentStatement, getRootStatement, getStatementEvaluatedAfter, getStatementEvaluatedBefore, getStaticType, setParentStatement

Methods inherited from class it.unive.lisa.program.cfg.statement.Statement

backwardSemantics, compareTo, getCFG, getEvaluationPredecessor, getEvaluationSuccessor, getLocation, getOffset, stopsExecution, throwsError

Methods inherited from class java.lang.Object

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

Methods inherited from interface it.unive.lisa.program.cfg.ProgramPoint

getProgram

Constructor Detail

VariableRef

public VariableRef(CFG cfg,
                   CodeLocation location,
                   java.lang.String name)

Builds the untyped variable reference, identified by its name. The type of this variable reference is Untyped.INSTANCE.

Parameters:

cfg - the cfg that this expression belongs to

location - the location of this variable reference

name - the name of this variable reference

VariableRef

public VariableRef(CFG cfg,
                   CodeLocation location,
                   java.lang.String name,
                   Type type)

Builds the variable reference, identified by its name, happening at the given location in the program.

Parameters:

cfg - the cfg that this expression belongs to

location - the location where the expression is defined within the program

name - the name of this variable

type - the type of this variable

Method Detail

setOffset

public int setOffset(int offset)

Description copied from interface: CodeNode

Sets the offset of this node to the given value, and then proceeds by setting the one of its nested nodes (if any) to subsequent values. The last offset used is returned.

Parameters:

offset - the offset to set

Returns:

the last offset used while setting the offsets of nested nodes

getName

public java.lang.String getName()

Yields the name of this variable.

Returns:

the name of this variable

hashCode

public int hashCode()

Overrides:

hashCode in class Expression

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class Expression

toString

public java.lang.String toString()

Specified by:

toString in class Statement

getVariable

public Variable getVariable()

Yields a Variable representing the referenced variable.

Returns:

the expression representing the variable

forwardSemantics

public <A extends AbstractState<A>> AnalysisState<A> forwardSemantics(AnalysisState<A> entryState,
                                                                      InterproceduralAnalysis<A> interprocedural,
                                                                      StatementStore<A> expressions)
                                                               throws SemanticException

Description copied from class: Statement

Computes the forward semantics of the statement, expressing how semantic information is transformed by the execution of this statement. This method is also responsible for recursively invoking the Statement.forwardSemantics(AnalysisState, InterproceduralAnalysis, StatementStore) of each nested Expression, saving the result of each call in expressions.

Specified by:

forwardSemantics in class Statement

Type Parameters:

A - the type of AbstractState

Parameters:

entryState - the entry state that represents the abstract values of each program variable and memory location when the execution reaches this statement

interprocedural - the interprocedural analysis of the program to analyze

expressions - the cache where analysis states of intermediate expressions must be stored

Returns:

the AnalysisState representing the abstract result of the execution of this statement

Throws:

SemanticException - if something goes wrong during the computation

accept

public <V> boolean accept(GraphVisitor<CFG,Statement,Edge,V> visitor,
                          V tool)

Description copied from interface: Node

Accepts the given GraphVisitor. Implementors of this method are responsible for invoking GraphVisitor.visit(Object, Graph, Node) on this node after Node.accept(GraphVisitor, Object) has been invoked on all nested nodes, if any. The visiting should stop at the first of such calls that return false.

Type Parameters:

V - the type of auxiliary tool that visitor can use

Parameters:

visitor - the visitor that is visiting the Graph containing this node

tool - the auxiliary tool that visitor can use

Returns:

whether or not the visiting should stop when this call returns, as decided by the visitor itself

getAnnotations

public Annotations getAnnotations()

Yields the annotations of this variable, retrieved from the variable table of the cfg this variable belongs to.

Returns:

the annotations of this variable.