Package it.unive.lisa.program.cfg.fixpoints

Class OptimizedBackwardFixpoint<A extends AbstractState<A>>

java.lang.Object

it.unive.lisa.util.datastructures.graph.algorithms.BackwardFixpoint<CFG,Statement,Edge,CFGFixpoint.CompoundState<A>>

it.unive.lisa.program.cfg.fixpoints.OptimizedBackwardFixpoint<A>

Type Parameters:

A - the type of AbstractState contained into the analysis state

public class OptimizedBackwardFixpoint<A extends AbstractState<A>>
extends BackwardFixpoint<CFG,Statement,Edge,CFGFixpoint.CompoundState<A>>

A fixpoint algorithm for a Graph, parametric to the Fixpoint.FixpointImplementation that one wants to use to compute the results. This fixpoint algorithms is optimized: it works exploiting the basic blocks of the target graph, and only yields approximations of widening points, stopping statements and user-defined hotspots.

Field Summary

Fields inherited from class it.unive.lisa.util.datastructures.graph.algorithms.BackwardFixpoint

ERROR, forceFullEvaluation, graph

Constructor Summary

Constructors

Constructor	Description
OptimizedBackwardFixpoint(CFG graph, boolean forceFullEvaluation, java.util.function.Predicate<Statement> hotspots)	Builds an optimized fixpoint for the given Graph.

Method Summary

Modifier and Type	Method	Description
java.util.Map<Statement,CFGFixpoint.CompoundState<A>>	fixpoint(java.util.Map<Statement,CFGFixpoint.CompoundState<A>> startingPoints, WorkingSet<Statement> ws, Fixpoint.FixpointImplementation<Statement,Edge,CFGFixpoint.CompoundState<A>> implementation, java.util.Map<Statement,CFGFixpoint.CompoundState<A>> initialResult)	Runs the fixpoint.

Methods inherited from class it.unive.lisa.util.datastructures.graph.algorithms.BackwardFixpoint

fixpoint, getExitState

Methods inherited from class java.lang.Object

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

Constructor Detail

OptimizedBackwardFixpoint

public OptimizedBackwardFixpoint(CFG graph,
                                 boolean forceFullEvaluation,
                                 java.util.function.Predicate<Statement> hotspots)

Builds an optimized fixpoint for the given Graph.

Parameters:

graph - the source graph

forceFullEvaluation - whether or not the fixpoint should evaluate all nodes independently of the fixpoint implementation

hotspots - the predicate to identify additional statements whose approximation must be preserved in the results

Method Detail

fixpoint

public java.util.Map<Statement,CFGFixpoint.CompoundState<A>> fixpoint(java.util.Map<Statement,CFGFixpoint.CompoundState<A>> startingPoints,
                                                                            WorkingSet<Statement> ws,
                                                                            Fixpoint.FixpointImplementation<Statement,Edge,CFGFixpoint.CompoundState<A>> implementation,
                                                                            java.util.Map<Statement,CFGFixpoint.CompoundState<A>> initialResult)
                                                                     throws FixpointException

Description copied from class: BackwardFixpoint

Runs the fixpoint. Invoking this method effectively recomputes the result: no caching on previous runs is executed.

Overrides:

fixpoint in class BackwardFixpoint<CFG,Statement,Edge,CFGFixpoint.CompoundState<A extends AbstractState<A>>>

Parameters:

startingPoints - a map containing all the nodes to start the fixpoint at, each mapped to its entry state.

ws - the instance of WorkingSet to use for the fixpoint

implementation - the Fixpoint.FixpointImplementation to use for running the fixpoint

initialResult - the map of initial result to use for running the fixpoint

Returns:

a mapping from each (reachable) node of the source graph to the fixpoint result computed at that node

Throws:

FixpointException - if something goes wrong during the fixpoint execution