Class NullPointerSolver<B extends ISSABasicBlock>

java.lang.Object

com.ibm.wala.fixedpoint.impl.AbstractFixedPointSolver<NullPointerState>

com.ibm.wala.fixedpoint.impl.DefaultFixedPointSolver<NullPointerState>

com.ibm.wala.dataflow.graph.DataflowSolver<B, NullPointerState>

com.ibm.wala.cfg.exc.intra.NullPointerSolver<B>

All Implemented Interfaces:

FixedPointConstants, IFixedPointSolver<NullPointerState>, VerboseAction

public class NullPointerSolver<B extends ISSABasicBlock>
extends DataflowSolver<B, NullPointerState>

Intraprocedural dataflow analysis to detect impossible NullPointerExceptions.

Author:

Juergen Graf <graf@kit.edu>

Nested Class Summary

Nested classes/interfaces inherited from class AbstractFixedPointSolver

AbstractFixedPointSolver.Statement

Field Summary

Fields inherited from class AbstractFixedPointSolver

DEFAULT_PERIODIC_MAINTENANCE_INTERVAL, DEFAULT_VERBOSE_INTERVAL, verbose, workList

Fields inherited from interface FixedPointConstants

CHANGED, CHANGED_AND_FIXED, CHANGED_MASK, FIXED_MASK, NOT_CHANGED, NOT_CHANGED_AND_FIXED, SIDE_EFFECT_MASK

Constructor Summary

Constructors

Constructor	Description
NullPointerSolver(NullPointerFrameWork<B> problem, int maxVarNum, B entry, IR ir, ParameterState initialState)
NullPointerSolver(NullPointerFrameWork<B> problem, int maxVarNum, IR ir, B entry)

Method Summary

Modifier and Type	Method	Description
protected NullPointerState	makeEdgeVariable(B src, B dst)
protected NullPointerState	makeNodeVariable(B n, boolean IN)
protected NullPointerState[]	makeStmtRHS(int size)

Methods inherited from class DataflowSolver

buildEquations, getEdge, getEdge, getIn, getOut, getProblem, initializeVariables, initializeWorkList

Methods inherited from class DefaultFixedPointSolver

getFixedPointSystem

Methods inherited from class AbstractFixedPointSolver

addAllStatementsToWorkList, addToWorkList, changedVariable, emptyWorkList, getMaxEvalBetweenTopo, getMinSizeForTopSort, getNumberOfEvaluations, getPeriodicMaintainInterval, getStatements, getTopologicalGrowthFactor, getVerboseInterval, incNumberOfEvaluations, initForFirstSolve, isChanged, isFixed, isSideEffect, lineBreak, newStatement, newStatement, newStatement, newStatement, newStatement, orderStatements, performVerboseAction, periodicMaintenance, removeStatement, setMaxEvalBetweenTopo, setMinEquationsForTopSort, setTopologicalGrowthFactor, solve, toString

Methods inherited from class Object

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

Constructor Details

NullPointerSolver

public NullPointerSolver(NullPointerFrameWork<B> problem,
 int maxVarNum,
 IR ir,
 B entry)

NullPointerSolver

public NullPointerSolver(NullPointerFrameWork<B> problem,
 int maxVarNum,
 B entry,
 IR ir,
 ParameterState initialState)

Method Details

makeEdgeVariable

protected NullPointerState makeEdgeVariable(B src,
 B dst)

Specified by:

makeEdgeVariable in class DataflowSolver<B extends ISSABasicBlock, NullPointerState>

makeNodeVariable

protected NullPointerState makeNodeVariable(B n,
 boolean IN)

Specified by:

makeNodeVariable in class DataflowSolver<B extends ISSABasicBlock, NullPointerState>

Parameters:

n - a node

Returns:

a fresh variable to represent the lattice value at the IN or OUT of n

makeStmtRHS

protected NullPointerState[] makeStmtRHS(int size)

Specified by:

makeStmtRHS in class AbstractFixedPointSolver<NullPointerState>