soot.jimple.toolkits.scalar.pre
Class DownSafetyAnalysis

java.lang.Object
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  +--soot.toolkits.scalar.FlowAnalysis
        |
        +--soot.toolkits.scalar.BackwardFlowAnalysis
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              +--soot.jimple.toolkits.scalar.pre.DownSafetyAnalysis

public class DownSafetyAnalysis
extends BackwardFlowAnalysis

Performs an DownSafe-analysis on the given graph. An expression is downsafe, if the computation will occur on every path from the current point down to the END.


Field Summary
 
Fields inherited from class soot.toolkits.scalar.FlowAnalysis
graph, unitToAfterFlow, unitToBeforeFlow
 
Constructor Summary
DownSafetyAnalysis(DirectedGraph dg)
          this constructor should not be used, and will throw a runtime-exception!
DownSafetyAnalysis(DirectedGraph dg, java.util.Map unitToGen, SideEffectTester sideEffect)
          this constructor automaticly performs the DownSafety-analysis.
the result of the analysis is as usual in FlowBefore (getFlowBefore()) and FlowAfter (getFlowAfter()).
DownSafetyAnalysis(DirectedGraph dg, java.util.Map unitToGen, SideEffectTester sideEffect, BoundedFlowSet set)
          this constructor automaticly performs the DownSafety-analysis.
the result of the analysis is as usual in FlowBefore (getFlowBefore()) and FlowAfter (getFlowAfter()).
as sets-operations are usually more efficient, if the original set comes from the same source, this allows to share sets.
 
Method Summary
protected  void copy(java.lang.Object source, java.lang.Object dest)
          Creates a copy of the source flow object in dest.
protected  void customizeInitialFlowGraph()
          Customize the initial flow graph.
protected  void flowThrough(java.lang.Object inValue, java.lang.Object unit, java.lang.Object outValue)
          Given the merge of the out sets, compute the in set for s.
protected  void merge(java.lang.Object in1, java.lang.Object in2, java.lang.Object out)
          Compute the merge of the in1 and in2 sets, putting the result into out.
protected  java.lang.Object newInitialFlow()
          Returns the flow object corresponding to the initial values for each graph node.
 
Methods inherited from class soot.toolkits.scalar.BackwardFlowAnalysis
doAnalysis, isForward
 
Methods inherited from class soot.toolkits.scalar.FlowAnalysis
entryInitialFlow, getFlowAfter, getFlowBefore
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

DownSafetyAnalysis

public DownSafetyAnalysis(DirectedGraph dg)
this constructor should not be used, and will throw a runtime-exception!


DownSafetyAnalysis

public DownSafetyAnalysis(DirectedGraph dg,
                          java.util.Map unitToGen,
                          SideEffectTester sideEffect)
this constructor automaticly performs the DownSafety-analysis.
the result of the analysis is as usual in FlowBefore (getFlowBefore()) and FlowAfter (getFlowAfter()).

Parameters:
dg - a CompleteUnitGraph.
unitToGen - the equivalentValue of each unit.
sideEffect - the SideEffectTester that performs kills.

DownSafetyAnalysis

public DownSafetyAnalysis(DirectedGraph dg,
                          java.util.Map unitToGen,
                          SideEffectTester sideEffect,
                          BoundedFlowSet set)
this constructor automaticly performs the DownSafety-analysis.
the result of the analysis is as usual in FlowBefore (getFlowBefore()) and FlowAfter (getFlowAfter()).
as sets-operations are usually more efficient, if the original set comes from the same source, this allows to share sets.

Parameters:
dg - a CompleteUnitGraph.
unitToGen - the equivalentValue of each unit.
sideEffect - the SideEffectTester that performs kills.
Method Detail

newInitialFlow

protected java.lang.Object newInitialFlow()
Description copied from class: FlowAnalysis
Returns the flow object corresponding to the initial values for each graph node.

Specified by:
newInitialFlow in class FlowAnalysis

customizeInitialFlowGraph

protected void customizeInitialFlowGraph()
Description copied from class: FlowAnalysis
Customize the initial flow graph. May be called from a concrete FlowAnalysis constructor to adjust, for instance, the value for the initial node.

Overrides:
customizeInitialFlowGraph in class FlowAnalysis

flowThrough

protected void flowThrough(java.lang.Object inValue,
                           java.lang.Object unit,
                           java.lang.Object outValue)
Description copied from class: FlowAnalysis
Given the merge of the out sets, compute the in set for s.

Specified by:
flowThrough in class FlowAnalysis

merge

protected void merge(java.lang.Object in1,
                     java.lang.Object in2,
                     java.lang.Object out)
Description copied from class: FlowAnalysis
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.

Specified by:
merge in class FlowAnalysis

copy

protected void copy(java.lang.Object source,
                    java.lang.Object dest)
Description copied from class: FlowAnalysis
Creates a copy of the source flow object in dest.

Specified by:
copy in class FlowAnalysis