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

Class NullLiteral

java.lang.Object

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

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

it.unive.lisa.program.cfg.statement.literal.Literal<java.lang.Object>

it.unive.lisa.program.cfg.statement.literal.NullLiteral

All Implemented Interfaces:

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

public class NullLiteral
extends Literal<java.lang.Object>

A literal representing the null constant.

Field Summary

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

offset

Constructor Summary

Constructors

Constructor	Description
NullLiteral(CFG cfg, CodeLocation location)	Builds the null literal, happening at the given location in the program.

Method Summary

Modifier and Type	Method	Description
<A extends AbstractState<A,H,V,T>,H extends HeapDomain<H>,V extends ValueDomain<V>,T extends TypeDomain<T>> AnalysisState<A,H,V,T>	semantics(AnalysisState<A,H,V,T> entryState, InterproceduralAnalysis<A,H,V,T> interprocedural, StatementStore<A,H,V,T> expressions)	Computes the semantics of the statement, expressing how semantic information is transformed by the execution of this statement.

Methods inherited from class it.unive.lisa.program.cfg.statement.literal.Literal

accept, equals, getValue, hashCode, setOffset, toString

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

getMetaVariables, getParentStatement, getRootStatement, getStatementEvaluatedBefore, getStaticType, setParentStatement

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

compareTo, getCFG, getEvaluationPredecessor, 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

NullLiteral

public NullLiteral(CFG cfg,
                   CodeLocation location)

Builds the null literal, happening at the given location in the program. The type of a null literal is NullType.

Parameters:

cfg - the cfg that this expression belongs to

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

Method Detail

semantics

public <A extends AbstractState<A,H,V,T>,H extends HeapDomain<H>,V extends ValueDomain<V>,T extends TypeDomain<T>> AnalysisState<A,H,V,T> semantics(AnalysisState<A,H,V,T> entryState,
                                                                                                                                                                                                          InterproceduralAnalysis<A,H,V,T> interprocedural,
                                                                                                                                                                                                          StatementStore<A,H,V,T> expressions)
                                                                                                                                                                                                   throws SemanticException

Description copied from class: Statement

Computes the 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.semantics(AnalysisState, InterproceduralAnalysis, StatementStore) of each nested Expression, saving the result of each call in expressions.

Overrides:

semantics in class Literal<java.lang.Object>

Type Parameters:

A - the type of AbstractState

H - the type of the HeapDomain

V - the type of the ValueDomain

T - the type of TypeDomain

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