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

java.lang.Object
  soot.toolkits.scalar.AbstractFlowAnalysis<N,A>

Type Parameters:

N - node type of the directed graph

A - abstraction type

Direct Known Subclasses:

BranchedFlowAnalysis, FlowAnalysis

public abstract class AbstractFlowAnalysis<N,A>
extends Object

An abstract class providing a metaframework for carrying out dataflow analysis. This class provides common methods and fields required by the BranchedFlowAnalysis and FlowAnalysis abstract classes.

Field Summary

protected Map<Stmt,A>	filterUnitToBeforeFlow Filtered: Maps graph nodes to IN sets.
protected DirectedGraph<N>	graph The graph being analysed.
protected Map<N,A>	unitToBeforeFlow Maps graph nodes to IN sets.

Constructor Summary

AbstractFlowAnalysis(DirectedGraph<N> graph)
Constructs a flow analysis on the given DirectedGraph.

Method Summary

protected abstract void	copy(A source, A dest) Creates a copy of the source flow object in dest.
protected abstract void	doAnalysis() Carries out the actual flow analysis.
protected abstract A	entryInitialFlow() Returns the initial flow value for entry/exit graph nodes.
A	getFlowBefore(N s) Accessor function returning value of IN set for s.
protected abstract boolean	isForward() Returns true if this analysis is forwards.
protected abstract void	merge(A in1, A in2, A out) Compute the merge of the in1 and in2 sets, putting the result into out.
protected void	merge(N succNode, A in1, A in2, A out) Merges in1 and in2 into out, just before node succNode.
protected void	mergeInto(N succNode, A inout, A in) Merges in into inout, just before node succNode.
protected abstract A	newInitialFlow() Returns the flow object corresponding to the initial values for each graph node.
protected boolean	treatTrapHandlersAsEntries() Determines whether entryInitialFlow() is applied to trap handlers.

Methods inherited from class java.lang.Object

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

Field Detail

unitToBeforeFlow

protected Map<N,A> unitToBeforeFlow

Maps graph nodes to IN sets.

filterUnitToBeforeFlow

protected Map<Stmt,A> filterUnitToBeforeFlow

Filtered: Maps graph nodes to IN sets.

graph

protected DirectedGraph<N> graph

The graph being analysed.

Constructor Detail

AbstractFlowAnalysis

public AbstractFlowAnalysis(DirectedGraph<N> graph)

Constructs a flow analysis on the given DirectedGraph.

Method Detail

newInitialFlow

protected abstract A newInitialFlow()

Returns the flow object corresponding to the initial values for each graph node.

entryInitialFlow

protected abstract A entryInitialFlow()

Returns the initial flow value for entry/exit graph nodes.

treatTrapHandlersAsEntries

protected boolean treatTrapHandlersAsEntries()

Determines whether entryInitialFlow() is applied to trap handlers.

isForward

protected abstract boolean isForward()

Returns true if this analysis is forwards.

merge

protected abstract void merge(A in1,
                              A in2,
                              A out)

Compute the merge of the in1 and in2 sets, putting the result into out. The behavior of this function depends on the implementation ( it may be necessary to check whether in1 and in2 are equal or aliased ). Used by the doAnalysis method.

merge

protected void merge(N succNode,
                     A in1,
                     A in2,
                     A out)

Merges in1 and in2 into out, just before node succNode. By default, this method just calls merge(A,A,A), ignoring the node.

copy

protected abstract void copy(A source,
                             A dest)

Creates a copy of the source flow object in dest.

doAnalysis

protected abstract void doAnalysis()

Carries out the actual flow analysis. Typically called from a concrete FlowAnalysis's constructor.

getFlowBefore

public A getFlowBefore(N s)

Accessor function returning value of IN set for s.

mergeInto

protected void mergeInto(N succNode,
                         A inout,
                         A in)

Merges in into inout, just before node succNode.