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

Class Length

  • All Implemented Interfaces:
    it.unive.lisa.program.cfg.ProgramPoint, it.unive.lisa.program.CodeElement, it.unive.lisa.util.datastructures.graph.code.CodeNode<it.unive.lisa.program.cfg.CFG,​it.unive.lisa.program.cfg.statement.Statement,​it.unive.lisa.program.cfg.edge.Edge>, it.unive.lisa.util.datastructures.graph.Node<it.unive.lisa.program.cfg.CFG,​it.unive.lisa.program.cfg.statement.Statement,​it.unive.lisa.program.cfg.edge.Edge>, java.lang.Comparable<it.unive.lisa.program.cfg.statement.Statement>
    public class Length
extends it.unive.lisa.program.cfg.statement.UnaryExpression
    An expression modeling the string length operation. The type of the operand must be StringType. The type of this expression is the NumericType.

    Since in most languages string operations are provided through calls to library functions, this class contains a field whose purpose is to optionally store a Statement that is rewritten to an instance of this class (i.e., a call to a NativeCFG modeling the library function). If present, such statement will be used as ProgramPoint for semantics computations. This allows subclasses to implement PluggableStatement easily without redefining the semantics provided by this class.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected it.unive.lisa.program.cfg.statement.Statement originating
      Statement that has been rewritten to this operation, if any.

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

        offset

    • Constructor Summary

      Constructors 
      Constructor Description
      Length​(it.unive.lisa.program.cfg.CFG cfg, it.unive.lisa.program.cfg.CodeLocation location, it.unive.lisa.program.cfg.statement.Expression parameter)
      Builds the length.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      <A extends it.unive.lisa.analysis.AbstractState<A>>
      it.unive.lisa.analysis.AnalysisState<A>      		 fwdUnarySemantics​(it.unive.lisa.interprocedural.InterproceduralAnalysis<A> interprocedural, it.unive.lisa.analysis.AnalysisState<A> state, it.unive.lisa.symbolic.SymbolicExpression expr, it.unive.lisa.analysis.StatementStore<A> expressions)  

      • Methods inherited from class it.unive.lisa.program.cfg.statement.UnaryExpression

        backwardSemanticsAux, bwdUnarySemantics, forwardSemanticsAux, getSubExpression

      • Methods inherited from class it.unive.lisa.program.cfg.statement.NaryExpression

        accept, backwardSemantics, equals, forwardSemantics, getConstructName, getOrder, getStatementEvaluatedAfter, getStatementEvaluatedBefore, getSubExpressions, hashCode, setOffset, toString

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

        getMetaVariables, getParentStatement, getRootStatement, getStaticType, setParentStatement

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

        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

    • Field Detail

      • originating

        protected it.unive.lisa.program.cfg.statement.Statement originating
        Statement that has been rewritten to this operation, if any. This is to accomodate the fact that, in most languages, string operations are performed through calls, and one might want to provide the semantics of those calls through NativeCFG that rewrites to instances of this class.

    • Constructor Detail

      • Length

        public Length​(it.unive.lisa.program.cfg.CFG cfg,
              it.unive.lisa.program.cfg.CodeLocation location,
              it.unive.lisa.program.cfg.statement.Expression parameter)
        Builds the length.
        Parameters:
        cfg - the CFG where this operation lies
        location - the code location where this operation is defined
        parameter - the operand of this operation

    • Method Detail

      • fwdUnarySemantics

        public <A extends it.unive.lisa.analysis.AbstractState<A>> it.unive.lisa.analysis.AnalysisState<A> fwdUnarySemantics​(it.unive.lisa.interprocedural.InterproceduralAnalysis<A> interprocedural,
                                                                                                                     it.unive.lisa.analysis.AnalysisState<A> state,
                                                                                                                     it.unive.lisa.symbolic.SymbolicExpression expr,
                                                                                                                     it.unive.lisa.analysis.StatementStore<A> expressions)
                                                                                                              throws it.unive.lisa.analysis.SemanticException
        Specified by:
        fwdUnarySemantics in class it.unive.lisa.program.cfg.statement.UnaryExpression
        Throws:
        it.unive.lisa.analysis.SemanticException