/* Soot - a J*va Optimization Framework
* Copyright (C) 1997-1999 Raja Vallee-Rai
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/*
* Modified by the Sable Research Group and others 1997-1999.
* See the 'credits' file distributed with Soot for the complete list of
* contributors. (Soot is distributed at http://www.sable.mcgill.ca/soot)
*/
package soot.toolkits.scalar;
import soot.options.*;
import soot.toolkits.graph.*;
import soot.*;
import soot.util.*;
import java.util.*;
// FSet version
/**
* Analysis that provides an implementation of the LocalDefs interface.
*/
public class SimpleLocalDefs implements LocalDefs
{
Map<LocalUnitPair, List> localUnitPairToDefs;
/**
* Computes the analysis given a UnitGraph computed from a method body.
* It is recommended that a ExceptionalUnitGraph (or similar) be provided
* for correct results in the case of exceptional control flow.
* @param g a graph on which to compute the analysis.
*
* @see ExceptionalUnitGraph
*/
public SimpleLocalDefs(UnitGraph g)
{
if(Options.v().time())
Timers.v().defsTimer.start();
if(Options.v().verbose())
G.v().out.println("[" + g.getBody().getMethod().getName() +
"] Constructing SimpleLocalDefs...");
LocalDefsFlowAnalysis analysis = new LocalDefsFlowAnalysis(g);
if(Options.v().time())
Timers.v().defsPostTimer.start();
// Build localUnitPairToDefs map
{
Iterator unitIt = g.iterator();
localUnitPairToDefs = new HashMap<LocalUnitPair, List>(g.size() * 2 + 1, 0.7f);
while(unitIt.hasNext())
{
Unit s = (Unit) unitIt.next();
Iterator boxIt = s.getUseBoxes().iterator();
while(boxIt.hasNext())
{
ValueBox box = (ValueBox) boxIt.next();
if(box.getValue() instanceof Local)
{
Local l = (Local) box.getValue();
LocalUnitPair pair = new LocalUnitPair(l, s);
if(!localUnitPairToDefs.containsKey(pair))
{
IntPair intPair = analysis.localToIntPair.get(l);
ArrayPackedSet value = (ArrayPackedSet) analysis.getFlowBefore(s);
List unitLocalDefs = value.toList(intPair.op1, intPair.op2);
localUnitPairToDefs.put(pair, Collections.unmodifiableList(unitLocalDefs));
}
}
}
}
}
if(Options.v().time())
Timers.v().defsPostTimer.end();
if(Options.v().time())
Timers.v().defsTimer.end();
if(Options.v().verbose())
G.v().out.println("[" + g.getBody().getMethod().getName() +
"] SimpleLocalDefs finished.");
}
public boolean hasDefsAt(Local l, Unit s)
{
return localUnitPairToDefs.containsKey( new LocalUnitPair(l,s) );
}
public List<Unit> getDefsOfAt(Local l, Unit s)
{
LocalUnitPair pair = new LocalUnitPair(l, s);
List<Unit> toReturn = localUnitPairToDefs.get(pair);
if(toReturn == null)
throw new RuntimeException("Illegal LocalDefs query; local " + l + " has no definition at " +
s.toString());
return toReturn;
}
/*
public List getDefsOfBefore(Local l, Unit s)
{
IntPair pair = (IntPair) analysis.localToIntPair.get(l);
FSet value = (FSet) analysis.getValueBeforeUnit(s);
List unitLocalDefs = value.toList(pair.op1, pair.op2);
return unitLocalDefs;
}*/
/*
Object[] elements = ((FSet) analysis.getValueBeforeUnit(s)).toArray();
List listOfDefs = new LinkedList();
// Extract those defs which correspond to this local
{
for(int i = 0; i < elements.length; i++)
{
DefinitionUnit d = (DefinitionUnit) elements[i];
if(d.getLeftOp() == l)
listOfDefs.add(d);
}
}
// Convert the array so that it's of an appropriate form
{
Object[] objects = listOfDefs.toArray();
DefinitionUnit[] defs = new DefinitionUnit[objects.length];
for(int i = 0; i < defs.length; i++)
defs[i] = (DefinitionUnit) objects[i];
return defs;
}
}
}
*/
/*
public DefinitionUnit[] getDefsOfAfter(Local l, Unit s)
{
Object[] elements = ((FSet) analysis.getValueAfterUnit(s)).toArray();
List listOfDefs = new LinkedList();
// Extract those defs which correspond to this local
{
for(int i = 0; i < elements.length; i++)
{
DefinitionUnit d = (DefinitionUnit) elements[i];
if(d.getLeftOp() == l)
listOfDefs.add(d);
}
}
// Convert the array so that it's of an appropriate form
{
Object[] objects = listOfDefs.toArray();
DefinitionUnit[] defs = new DefinitionUnit[objects.length];
for(int i = 0; i < defs.length; i++)
defs[i] = (DefinitionUnit) objects[i];
return defs;
}
}
public DefinitionUnit[] getDefsBefore(Unit s)
{
Object[] elements = ((FSet) analysis.getValueBeforeUnit(s)).toArray();
DefinitionUnit[] defs = new DefinitionUnit[elements.length];
for(int i = 0; i < elements.length; i++)
defs[i] = (DefinitionUnit) elements[i];
return defs;
}
public DefinitionUnit[] getDefsAfter(Unit s)
{
Object[] elements = ((FSet) analysis.getValueAfterUnit(s)).toArray();
DefinitionUnit[] defs = new DefinitionUnit[elements.length];
for(int i = 0; i < elements.length; i++)
defs[i] = (DefinitionUnit) elements[i];
return defs;
}
*/
}
class IntPair
{
int op1, op2;
public IntPair(int op1, int op2)
{
this.op1 = op1;
this.op2 = op2;
}
}
class LocalDefsFlowAnalysis extends ForwardFlowAnalysis
{
FlowSet emptySet;
Map<Local, BoundedFlowSet> localToPreserveSet;
Map<Local, IntPair> localToIntPair;
public LocalDefsFlowAnalysis(UnitGraph g)
{
super(g);
Object[] defs;
FlowUniverse defUniverse;
if(Options.v().time())
Timers.v().defsSetupTimer.start();
// Create a list of all the definitions and group defs of the same local together
{
Map<Local, ArrayList> localToDefList = new HashMap<Local, ArrayList>(g.getBody().getLocalCount() * 2 + 1, 0.7f);
// Initialize the set of defs for each local to empty
{
Iterator localIt = g.getBody().getLocals().iterator();
while(localIt.hasNext())
{
Local l = (Local) localIt.next();
localToDefList.put(l, new ArrayList());
}
}
// Fill the sets up
{
Iterator it = g.iterator();
while(it.hasNext())
{
Unit s = (Unit) it.next();
List defBoxes = s.getDefBoxes();
if(!defBoxes.isEmpty()) {
if(!(defBoxes.size() ==1))
throw new RuntimeException("invalid number of def boxes");
if(((ValueBox)defBoxes.get(0)).getValue() instanceof Local) {
Local defLocal = (Local) ((ValueBox)defBoxes.get(0)).getValue();
List<Unit> l = localToDefList.get(defLocal);
if(l == null)
throw new RuntimeException("local " + defLocal + " is used but not declared!");
else
l.add(s);
}
}
}
}
// Generate the list & localToIntPair
{
Iterator it = g.getBody().getLocals().iterator();
List defList = new LinkedList();
int startPos = 0;
localToIntPair = new HashMap<Local, IntPair>(g.getBody().getLocalCount() * 2 + 1, 0.7f);
// For every local, add all its defs
{
while(it.hasNext())
{
Local l = (Local) it.next();
Iterator jt = localToDefList.get(l).iterator();
int endPos = startPos - 1;
while(jt.hasNext())
{
defList.add(jt.next());
endPos++;
}
localToIntPair.put(l, new IntPair(startPos, endPos));
// G.v().out.println(startPos + ":" + endPos);
startPos = endPos + 1;
}
}
defs = defList.toArray();
defUniverse = new ArrayFlowUniverse(defs);
}
}
emptySet = new ArrayPackedSet(defUniverse);
// Create the preserve sets for each local.
{
Map<Local, FlowSet> localToKillSet = new HashMap<Local, FlowSet>(g.getBody().getLocalCount() * 2 + 1, 0.7f);
localToPreserveSet = new HashMap<Local, BoundedFlowSet>(g.getBody().getLocalCount() * 2 + 1, 0.7f);
Chain locals = g.getBody().getLocals();
// Initialize to empty set
{
Iterator localIt = locals.iterator();
while(localIt.hasNext())
{
Local l = (Local) localIt.next();
localToKillSet.put(l, emptySet.clone());
}
}
for (Object element : defs) {
Unit s = (Unit) element;
List defBoxes = s.getDefBoxes();
if(!(defBoxes.size() ==1))
throw new RuntimeException("SimpleLocalDefs: invalid number of def boxes");
if(((ValueBox)defBoxes.get(0)).getValue() instanceof Local) {
Local defLocal = (Local) ((ValueBox)defBoxes.get(0)).getValue();
BoundedFlowSet killSet = (BoundedFlowSet) localToKillSet.get(defLocal);
killSet.add(s, killSet);
}
}
// Store complement
{
Iterator localIt = locals.iterator();
while(localIt.hasNext())
{
Local l = (Local) localIt.next();
BoundedFlowSet killSet = (BoundedFlowSet) localToKillSet.get(l);
killSet.complement(killSet);
localToPreserveSet.put(l, killSet);
}
}
}
if(Options.v().time())
Timers.v().defsSetupTimer.end();
if(Options.v().time())
Timers.v().defsAnalysisTimer.start();
doAnalysis();
if(Options.v().time())
Timers.v().defsAnalysisTimer.end();
}
protected Object newInitialFlow()
{
return emptySet.clone();
}
protected Object entryInitialFlow()
{
return emptySet.clone();
}
protected void flowThrough(Object inValue, Object d, Object outValue)
{
FlowSet in = (FlowSet) inValue, out = (FlowSet) outValue;
Unit unit = (Unit)d;
List defBoxes = unit.getDefBoxes();
if(!defBoxes.isEmpty()) {
if(!(defBoxes.size() ==1))
throw new RuntimeException("SimpleLocalDefs: invalid number of def boxes");
Value value = ((ValueBox)defBoxes.get(0)).getValue();
if(value instanceof Local) {
Local defLocal = (Local) value;
// Perform kill on value
in.intersection(localToPreserveSet.get(defLocal), out);
// Perform generation
out.add(unit, out);
} else {
in.copy(out);
return;
}
}
else
in.copy(out);
}
protected void copy(Object source, Object dest)
{
FlowSet sourceSet = (FlowSet) source,
destSet = (FlowSet) dest;
sourceSet.copy(destSet);
}
protected void merge(Object in1, Object in2, Object out)
{
FlowSet inSet1 = (FlowSet) in1,
inSet2 = (FlowSet) in2;
FlowSet outSet = (FlowSet) out;
inSet1.union(inSet2, outSet);
}
}