/* Soot - a J*va Optimization Framework
* Copyright (C) 2005 Nomair A. Naeem
*
* 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.
*/
package soot.dava.toolkits.base.AST.transformations;
import soot.*;
import java.util.*;
import soot.dava.internal.AST.*;
import soot.dava.toolkits.base.AST.analysis.*;
/*
Nomair A. Naeem 21-FEB-2005
In the depthFirstAdaptor children of a ASTNode
are gotten in three ways
a, ASTStatementSequenceNode uses one way see caseASTStatementSequenceNode in DepthFirstAdapter
b, ASTTryNode uses another way see caseASTTryNode in DepthFirstAdapter
c, All other nodes use normalRetrieving method to retrieve the children
TO MAKE CODE EFFECIENT BLOCK THE ANALYSIS TO GOING INTO STATEMENTS
this is done by overriding the caseASTStatementSequenceNode
Current tasks of the cleaner:
*/
public class LoopStrengthener extends DepthFirstAdapter{
public LoopStrengthener(){
}
public LoopStrengthener(boolean verbose){
super(verbose);
}
public void caseASTStatementSequenceNode(ASTStatementSequenceNode node){
}
/*
Note the ASTNode in this case can be any of the following:
ASTMethodNode
ASTSwitchNode
ASTIfNode
ASTIfElseNode
ASTUnconditionalWhileNode
ASTWhileNode
ASTDoWhileNode
ASTForLoopNode
ASTLabeledBlockNode
ASTSynchronizedBlockNode
*/
public void normalRetrieving(ASTNode node){
if(node instanceof ASTSwitchNode){
dealWithSwitchNode((ASTSwitchNode)node);
return;
}
//from the Node get the subBodes
Iterator<Object> sbit = node.get_SubBodies().iterator();
//onlyASTIfElseNode has 2 subBodies but we need to deal with that
int subBodyNumber=0;
while (sbit.hasNext()) {
Object subBody = sbit.next();
Iterator it = ((List) subBody).iterator();
int nodeNumber=0;
//go over the ASTNodes in this subBody and apply
while (it.hasNext()){
ASTNode temp = (ASTNode) it.next();
if(temp instanceof ASTWhileNode || temp instanceof ASTUnconditionalLoopNode ||
temp instanceof ASTDoWhileNode){
ASTNode oneNode=getOnlySubNode(temp);
if(oneNode !=null){
List<ASTNode> newNode=null;
if(oneNode instanceof ASTIfNode){
newNode=StrengthenByIf.getNewNode(temp,(ASTIfNode)oneNode);
}
else if (oneNode instanceof ASTIfElseNode){
newNode=StrengthenByIfElse.getNewNode(temp,(ASTIfElseNode)oneNode);
}
if(newNode!=null){
//some pattern was matched
//replace the temp node with the newNode
replaceNode(node,subBodyNumber,nodeNumber,temp,newNode);
UselessLabelFinder.v().findAndKill(node);
}
}
}
temp.apply(this);
nodeNumber++;
}
subBodyNumber++;
}//end of going over subBodies
}
public void caseASTTryNode(ASTTryNode node){
inASTTryNode(node);
//get try body
List<Object> tryBody = node.get_TryBody();
Iterator<Object> it = tryBody.iterator();
int nodeNumber=0;
//go over the ASTNodes and apply
while (it.hasNext()){
ASTNode temp = (ASTNode) it.next();
if(temp instanceof ASTWhileNode || temp instanceof ASTUnconditionalLoopNode ||
temp instanceof ASTDoWhileNode){
ASTNode oneNode=getOnlySubNode(temp);
if(oneNode !=null){
List<ASTNode> newNode=null;
if(oneNode instanceof ASTIfNode){
newNode=StrengthenByIf.getNewNode(temp,(ASTIfNode)oneNode);
}
else if (oneNode instanceof ASTIfElseNode){
newNode=StrengthenByIfElse.getNewNode(temp,(ASTIfElseNode)oneNode);
}
if(newNode!=null){
//some pattern was matched
//replace the temp node with the newNode
List<Object> newBody=createNewSubBody(tryBody,nodeNumber,temp,newNode);
if(newBody!=null){
//something did not go wrong
node.replaceTryBody(newBody);
G.v().ASTTransformations_modified = true;
//System.out.println("strengthened loop within trybody");
}
UselessLabelFinder.v().findAndKill(node);
}
}
}//it was a loop node
temp.apply(this);
nodeNumber++;
}
Map<Object, Object> exceptionMap = node.get_ExceptionMap();
Map<Object, Object> paramMap = node.get_ParamMap();
//get catch list and apply on the following
// a, type of exception caught
// b, local of exception
// c, catchBody
List<Object> catchList = node.get_CatchList();
Iterator<Object> itBody=null;
it = catchList.iterator();
while (it.hasNext()) {
ASTTryNode.container catchBody = (ASTTryNode.container)it.next();
SootClass sootClass = ((SootClass)exceptionMap.get(catchBody));
Type type = sootClass.getType();
//apply on type of exception
caseType(type);
//apply on local of exception
Local local = (Local)paramMap.get(catchBody);
decideCaseExprOrRef(local);
//apply on catchBody
List<Object> body = (List<Object>)catchBody.o;
itBody = body.iterator();
nodeNumber=0;
//go over the ASTNodes and apply
while (itBody.hasNext()){
ASTNode temp = (ASTNode) itBody.next();
if(temp instanceof ASTWhileNode || temp instanceof ASTUnconditionalLoopNode ||
temp instanceof ASTDoWhileNode){
ASTNode oneNode=getOnlySubNode(temp);
if(oneNode !=null){
List<ASTNode> newNode=null;
if(oneNode instanceof ASTIfNode){
newNode=StrengthenByIf.getNewNode(temp,(ASTIfNode)oneNode);
}
else if (oneNode instanceof ASTIfElseNode){
newNode=StrengthenByIfElse.getNewNode(temp,(ASTIfElseNode)oneNode);
}
if(newNode!=null){
//some pattern was matched
//replace the temp node with the newNode
List<Object> newBody=createNewSubBody(body,nodeNumber,temp,newNode);
if(newBody!=null){
//something did not go wrong
catchBody.replaceBody(newBody);
G.v().ASTTransformations_modified = true;
//System.out.println("strengthened loop within catchbody");
}
UselessLabelFinder.v().findAndKill(node);
}
}
}//it was a loop node
temp.apply(this);
nodeNumber++;
}
}
outASTTryNode(node);
}
private void dealWithSwitchNode(ASTSwitchNode node){
//do a depthfirst on elements of the switchNode
List<Object> indexList = node.getIndexList();
Map<Object, List<Object>> index2BodyList = node.getIndex2BodyList();
Iterator<Object> it = indexList.iterator();
while (it.hasNext()) {//going through all the cases of the switch statement
Object currentIndex = it.next();
List<Object> body = index2BodyList.get( currentIndex);
if (body != null){
//this body is a list of ASTNodes
Iterator<Object> itBody = body.iterator();
int nodeNumber=0;
//go over the ASTNodes and apply
while (itBody.hasNext()){
ASTNode temp = (ASTNode) itBody.next();
if(temp instanceof ASTWhileNode || temp instanceof ASTUnconditionalLoopNode ||
temp instanceof ASTDoWhileNode){
ASTNode oneNode=getOnlySubNode(temp);
if(oneNode !=null){
List<ASTNode> newNode=null;
if(oneNode instanceof ASTIfNode){
newNode=StrengthenByIf.getNewNode(temp,(ASTIfNode)oneNode);
}
else if (oneNode instanceof ASTIfElseNode){
newNode=StrengthenByIfElse.getNewNode(temp,(ASTIfElseNode)oneNode);
}
if(newNode!=null){
//some pattern was matched
//replace the temp node with the newNode
List<Object> newBody=createNewSubBody(body,nodeNumber,temp,newNode);
if(newBody!=null){
//something did not go wrong put this body in the Map
index2BodyList.put(currentIndex,newBody);
//replace in actual switchNode
node.replaceIndex2BodyList(index2BodyList);
G.v().ASTTransformations_modified = true;
//System.out.println("strengthened loop within switch body");
}
UselessLabelFinder.v().findAndKill(node);
}
}
}//it was a loop node
temp.apply(this);
nodeNumber++;
}
}
}
}
/*
Given an ASTNode as input this method checks the following:
1, The node is either ASTWhile, ASTDoWhile or ASTUnconditionalLoop
2, The node has one subBody
3, The onlySubBody has one node
it returns the only node in the only SubBody
*/
private ASTNode getOnlySubNode(ASTNode node){
if(!(node instanceof ASTWhileNode || node instanceof ASTDoWhileNode ||
node instanceof ASTUnconditionalLoopNode)){
//not one of these loops
return null;
}
List<Object> subBodies = node.get_SubBodies();
if(subBodies.size()!=1){
//we are coming from loop nodes so subBodies should always be one
return null;
}
List subBody = (List)subBodies.get(0);
if(subBody.size()!=1){
//only want the case which the subBody has a single node
return null;
}
return (ASTNode)subBody.get(0);
}
/*
- Go through the node bodies till you find subBodyNumber
- Go through this subBody until you find nodeNumber
- This is the temp node Replace it with the newNodes
Node is the node which contains the loop node
subBodyNumber is the subBody which of the node which contains the loopNode
nodeNumber is the location of the loopNode in the subBody
newNode is the loopNode which will replace the old loopNode
*/
private void replaceNode(ASTNode node,int subBodyNumber,int nodeNumber,ASTNode loopNode,List<ASTNode> newNode){
if(!(node instanceof ASTIfElseNode)){
//these are the nodes which always have one subBody
List<Object> subBodies = node.get_SubBodies();
if(subBodies.size()!=1){
//there is something wrong
throw new RuntimeException("Please report this benchmark to the programmer");
}
List<Object> onlySubBody = (List<Object>)subBodies.get(0);
/*
The onlySubBody contains the loopNode to be replaced
at location given by the nodeNumber variable
*/
List<Object> newBody = createNewSubBody(onlySubBody,nodeNumber,loopNode,newNode);
if(newBody==null){
//something went wrong
return;
}
if(node instanceof ASTMethodNode){
((ASTMethodNode)node).replaceBody(newBody);
G.v().ASTTransformations_modified = true;
//System.out.println("Stenghtened Loop");
}
else if(node instanceof ASTSynchronizedBlockNode){
((ASTSynchronizedBlockNode)node).replaceBody(newBody);
G.v().ASTTransformations_modified = true;
//System.out.println("Stenghtened Loop in synchblock");
}
else if(node instanceof ASTLabeledBlockNode){
((ASTLabeledBlockNode)node).replaceBody(newBody);
G.v().ASTTransformations_modified = true;
//System.out.println("Stenghtened Loop in labeledblock node");
}
else if(node instanceof ASTUnconditionalLoopNode){
((ASTUnconditionalLoopNode)node).replaceBody(newBody);
G.v().ASTTransformations_modified = true;
//System.out.println("Stenghtened Loop in unconditionalloopNode");
}
else if(node instanceof ASTIfNode){
((ASTIfNode)node).replaceBody(newBody);
G.v().ASTTransformations_modified = true;
//System.out.println("Stenghtened Loop in ifnode");
}
else if(node instanceof ASTWhileNode){
((ASTWhileNode)node).replaceBody(newBody);
G.v().ASTTransformations_modified = true;
//System.out.println("Stenghtened Loop in whilenode");
}
else if(node instanceof ASTDoWhileNode){
((ASTDoWhileNode)node).replaceBody(newBody);
G.v().ASTTransformations_modified = true;
//System.out.println("Stenghtened Loop in dowhile node");
}
else {
//there is no other case something is wrong if we get here
return;
}
}
else{//its an ASTIfElseNode
//if its an ASIfElseNode then check which Subbody has the labeledBlock
if(subBodyNumber!=0 && subBodyNumber!=1){
//something bad is happening dont do nothin
//System.out.println("Error-------not modifying AST");
return;
}
List<Object> subBodies = node.get_SubBodies();
if(subBodies.size()!=2){
//there is something wrong
throw new RuntimeException("Please report this benchmark to the programmer");
}
List<Object> toModifySubBody = (List<Object>)subBodies.get(subBodyNumber);
/*
The toModifySubBody contains the labeledBlockNode to be removed
at location given by the nodeNumber variable
*/
List<Object> newBody = createNewSubBody(toModifySubBody,nodeNumber,loopNode,newNode);
if(newBody==null){
//something went wrong
return;
}
if(subBodyNumber==0){
//the if body was modified
//System.out.println("Stenghtened Loop");
G.v().ASTTransformations_modified = true;
((ASTIfElseNode)node).replaceBody(newBody,(List<Object>)subBodies.get(1));
}
else if(subBodyNumber==1){
//else body was modified
//System.out.println("Stenghtened Loop");
G.v().ASTTransformations_modified = true;
((ASTIfElseNode)node).replaceBody((List<Object>)subBodies.get(0),newBody);
}
else{//realllly shouldnt come here
//something bad is happening dont do nothin
//System.out.println("Error-------not modifying AST");
return;
}
}//end of ASTIfElseNode
}
public static List<Object> createNewSubBody(List<Object> oldSubBody,int nodeNumber,ASTNode oldNode,List<ASTNode> newNode){
//create a new SubBody
List<Object> newSubBody = new ArrayList<Object>();
//this is an iterator of ASTNodes
Iterator<Object> it = oldSubBody.iterator();
//copy to newSubBody all nodes until you get to nodeNumber
int index=0;
while(index!=nodeNumber ){
if(!it.hasNext()){
return null;
}
newSubBody.add(it.next());
index++;
}
//at this point the iterator is pointing to the ASTNode to be removed
//just to make sure check this
ASTNode toRemove = (ASTNode)it.next();
if(toRemove.toString().compareTo(oldNode.toString())!=0){
System.out.println("The replace nodes dont match please report benchmark to developer");
return null;
}
else{
//not adding the oldNode into the newSubBody but adding its replacement
newSubBody.addAll(newNode);
}
//add any remaining nodes in the oldSubBody to the new one
while(it.hasNext()){
newSubBody.add(it.next());
}
//newSubBody is ready return it
return newSubBody;
}
}