soot.toolkits.scalar

Class FlowAnalysis<N,A>

java.lang.Object

soot.toolkits.scalar.AbstractFlowAnalysis<N,A>

soot.toolkits.scalar.FlowAnalysis<N,A>

Direct Known Subclasses:

BackwardFlowAnalysis, ForwardFlowAnalysis

public abstract class FlowAnalysis<N,A>
extends AbstractFlowAnalysis<N,A>

An abstract class providing a framework for carrying out dataflow analysis. Subclassing either BackwardFlowAnalysis or ForwardFlowAnalysis and providing implementations for the abstract methods will allow Soot to compute the corresponding flow analysis.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.Map<N,A>	filterUnitToAfterFlow Filtered: Maps graph nodes to OUT sets.
protected java.util.Map<N,A>	unitToAfterFlow Maps graph nodes to OUT sets.

Fields inherited from class soot.toolkits.scalar.AbstractFlowAnalysis

filterUnitToBeforeFlow, graph, unitToBeforeFlow

Constructor Summary

Constructors

Constructor and Description
FlowAnalysis(DirectedGraph<N> graph) Constructs a flow analysis on the given DirectedGraph.

Method Summary

Modifier and Type	Method and Description
protected Orderer<N>	constructOrderer() Default implementation constructing a PseudoTopologicalOrderer.
protected abstract void	flowThrough(A in, N d, A out) Given the merge of the out sets, compute the in set for s (or in to out, depending on direction).
A	getFlowAfter(N s) Accessor function returning value of OUT set for s.

Methods inherited from class soot.toolkits.scalar.AbstractFlowAnalysis

copy, doAnalysis, entryInitialFlow, getFlowBefore, isForward, merge, merge, mergeInto, newInitialFlow, treatTrapHandlersAsEntries

Methods inherited from class java.lang.Object

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

Field Detail

unitToAfterFlow

protected java.util.Map<N,A> unitToAfterFlow

Maps graph nodes to OUT sets.

filterUnitToAfterFlow

protected java.util.Map<N,A> filterUnitToAfterFlow

Filtered: Maps graph nodes to OUT sets.

Constructor Detail

FlowAnalysis

public FlowAnalysis(DirectedGraph<N> graph)

Constructs a flow analysis on the given DirectedGraph.

Method Detail

flowThrough

protected abstract void flowThrough(A in,
                                    N d,
                                    A out)

Given the merge of the out sets, compute the in set for s (or in to out, depending on direction). This function often causes confusion, because the same interface is used for both forward and backward flow analyses. The first parameter is always the argument to the flow function (i.e. it is the "in" set in a forward analysis and the "out" set in a backward analysis), and the third parameter is always the result of the flow function (i.e. it is the "out" set in a forward analysis and the "in" set in a backward analysis).

getFlowAfter

public A getFlowAfter(N s)

Accessor function returning value of OUT set for s.

constructOrderer

protected Orderer<N> constructOrderer()

Default implementation constructing a PseudoTopologicalOrderer.

Returns:

an Orderer to order the nodes for the fixed-point iteration