/* Soot - a J*va Optimization Framework
* Copyright (C) 1997-2000 Etienne Gagnon. All rights reserved.
*
* 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.jimple.toolkits.typing.integer;
import soot.*;
import soot.jimple.*;
import java.util.*;
import java.io.*;
/**
* This class resolves the type of local variables.
**/
public class TypeResolver
{
/** All type variable instances **/
private final List<TypeVariable> typeVariableList = new ArrayList<TypeVariable>();
/** Hashtable: [TypeNode or Local] -> TypeVariable **/
private final Map<Object, TypeVariable> typeVariableMap = new HashMap<Object, TypeVariable>();
private final JimpleBody stmtBody;
final TypeVariable BOOLEAN = typeVariable(ClassHierarchy.v().BOOLEAN);
final TypeVariable BYTE = typeVariable(ClassHierarchy.v().BYTE);
final TypeVariable SHORT = typeVariable(ClassHierarchy.v().SHORT);
final TypeVariable CHAR = typeVariable(ClassHierarchy.v().CHAR);
final TypeVariable INT = typeVariable(ClassHierarchy.v().INT);
final TypeVariable TOP = typeVariable(ClassHierarchy.v().TOP);
final TypeVariable R0_1 = typeVariable(ClassHierarchy.v().R0_1);
final TypeVariable R0_127 = typeVariable(ClassHierarchy.v().R0_127);
final TypeVariable R0_32767 = typeVariable(ClassHierarchy.v().R0_32767);
private static final boolean DEBUG = false;
// categories for type variables (solved = hard, unsolved = soft)
private List<TypeVariable> unsolved;
private List<TypeVariable> solved;
/** Get type variable for the given local. **/
TypeVariable typeVariable(Local local)
{
TypeVariable result = typeVariableMap.get(local);
if(result == null)
{
int id = typeVariableList.size();
typeVariableList.add(null);
result = new TypeVariable(id, this);
typeVariableList.set(id, result);
typeVariableMap.put(local, result);
if(DEBUG)
{
G.v().out.println("[LOCAL VARIABLE \"" + local + "\" -> " + id + "]");
}
}
return result;
}
/** Get type variable for the given type node. **/
public TypeVariable typeVariable(TypeNode typeNode)
{
TypeVariable result = typeVariableMap.get(typeNode);
if(result == null)
{
int id = typeVariableList.size();
typeVariableList.add(null);
result = new TypeVariable(id, this, typeNode);
typeVariableList.set(id, result);
typeVariableMap.put(typeNode, result);
}
return result;
}
/** Get type variable for the given type. **/
public TypeVariable typeVariable(Type type)
{
return typeVariable(ClassHierarchy.v().typeNode(type));
}
/** Get new type variable **/
public TypeVariable typeVariable()
{
int id = typeVariableList.size();
typeVariableList.add(null);
TypeVariable result = new TypeVariable(id, this);
typeVariableList.set(id, result);
return result;
}
private TypeResolver(JimpleBody stmtBody)
{
this.stmtBody = stmtBody;
}
public static void resolve(JimpleBody stmtBody)
{
if(DEBUG)
{
G.v().out.println(stmtBody.getMethod());
}
try
{
TypeResolver resolver = new TypeResolver(stmtBody);
resolver.resolve_step_1();
}
catch(TypeException e1)
{
if(DEBUG)
{
G.v().out.println("[integer] Step 1 Exception-->" + e1.getMessage());
}
try
{
TypeResolver resolver = new TypeResolver(stmtBody);
resolver.resolve_step_2();
}
catch(TypeException e2)
{
StringWriter st = new StringWriter();
PrintWriter pw = new PrintWriter(st);
e2.printStackTrace(pw);
pw.close();
throw new RuntimeException(st.toString());
}
}
}
private void debug_vars(String message)
{
if(DEBUG)
{
int count = 0;
G.v().out.println("**** START:" + message);
for (TypeVariable var : typeVariableList) {
G.v().out.println(count++ + " " + var);
}
G.v().out.println("**** END:" + message);
}
}
private void resolve_step_1() throws TypeException
{
collect_constraints_1();
debug_vars("constraints");
compute_approximate_types();
merge_connected_components();
debug_vars("components");
merge_single_constraints();
debug_vars("single");
assign_types_1();
debug_vars("assign");
try
{
check_constraints();
}
catch(TypeException e)
{
if(DEBUG)
{
G.v().out.println("[integer] Step 1(check) Exception [" + stmtBody.getMethod() + "]-->" + e.getMessage());
}
check_and_fix_constraints();
}
}
private void resolve_step_2() throws TypeException
{
collect_constraints_2();
compute_approximate_types();
assign_types_2();
check_and_fix_constraints();
}
private void collect_constraints_1()
{
ConstraintCollector collector = new ConstraintCollector(this, true);
for( Iterator stmtIt = stmtBody.getUnits().iterator(); stmtIt.hasNext(); ) {
final Stmt stmt = (Stmt) stmtIt.next();
if(DEBUG)
{
G.v().out.print("stmt: ");
}
collector.collect(stmt, stmtBody);
if(DEBUG)
{
G.v().out.println(stmt);
}
}
}
private void collect_constraints_2()
{
ConstraintCollector collector = new ConstraintCollector(this, false);
for( Iterator stmtIt = stmtBody.getUnits().iterator(); stmtIt.hasNext(); ) {
final Stmt stmt = (Stmt) stmtIt.next();
if(DEBUG)
{
G.v().out.print("stmt: ");
}
collector.collect(stmt, stmtBody);
if(DEBUG)
{
G.v().out.println(stmt);
}
}
}
private void merge_connected_components() throws TypeException
{
compute_solved();
List<TypeVariable> list = new LinkedList<TypeVariable>();
list.addAll(solved);
list.addAll(unsolved);
StronglyConnectedComponents.merge(list);
}
private void merge_single_constraints() throws TypeException
{
boolean modified = true;
while(modified)
{
modified = false;
refresh_solved();
for (TypeVariable var : unsolved) {
List<TypeVariable> children_to_remove = new LinkedList<TypeVariable>();
TypeNode lca = null;
var.fixChildren();
for (TypeVariable child : var.children()) {
TypeNode type = child.type();
if(type != null)
{
children_to_remove.add(child);
if(lca == null)
{
lca = type;
}
else
{
lca = lca.lca_1(type);
}
}
}
if(lca != null)
{
if(DEBUG)
{
if(lca == ClassHierarchy.v().TOP)
{
G.v().out.println("*** TOP *** " + var);
for (TypeVariable typeVariable : children_to_remove) {
G.v().out.println("-- " + typeVariable);
}
}
}
for (TypeVariable child : children_to_remove) {
var.removeChild(child);
}
var.addChild(typeVariable(lca));
}
if(var.children().size() == 1)
{
TypeVariable child = var.children().get(0);
TypeNode type = child.type();
if(type == null || type.type() != null)
{
var.union(child);
modified = true;
}
}
}
if(!modified)
{
for (TypeVariable var : unsolved) {
List<TypeVariable> parents_to_remove = new LinkedList<TypeVariable>();
TypeNode gcd = null;
var.fixParents();
for (TypeVariable parent : var.parents()) {
TypeNode type = parent.type();
if(type != null)
{
parents_to_remove.add(parent);
if(gcd == null)
{
gcd = type;
}
else
{
gcd = gcd.gcd_1(type);
}
}
}
if(gcd != null)
{
for (TypeVariable parent : parents_to_remove) {
var.removeParent(parent);
}
var.addParent(typeVariable(gcd));
}
if(var.parents().size() == 1)
{
TypeVariable parent = var.parents().get(0);
TypeNode type = parent.type();
if(type == null || type.type() != null)
{
var.union(parent);
modified = true;
}
}
}
}
if(!modified)
{
for (TypeVariable var : unsolved) {
if(var.type() == null && var.inv_approx() != null && var.inv_approx().type() != null)
{
if(DEBUG)
{
G.v().out.println("*** I->" + var.inv_approx().type() + " *** " + var);
}
var.union(typeVariable(var.inv_approx()));
modified = true;
}
}
}
if(!modified)
{
for (TypeVariable var : unsolved) {
if(var.type() == null && var.approx() != null && var.approx().type() != null)
{
if(DEBUG)
{
G.v().out.println("*** A->" + var.approx().type() + " *** " + var);
}
var.union(typeVariable(var.approx()));
modified = true;
}
}
}
if(!modified)
{
for (TypeVariable var : unsolved) {
if(var.type() == null && var.approx() == ClassHierarchy.v().R0_32767)
{
if(DEBUG)
{
G.v().out.println("*** R->SHORT *** " + var);
}
var.union(SHORT);
modified = true;
}
}
}
if(!modified)
{
for (TypeVariable var : unsolved) {
if(var.type() == null && var.approx() == ClassHierarchy.v().R0_127)
{
if(DEBUG)
{
G.v().out.println("*** R->BYTE *** " + var);
}
var.union(BYTE);
modified = true;
}
}
}
if(!modified)
{
for (TypeVariable var : R0_1.parents()) {
if(var.type() == null && var.approx() == ClassHierarchy.v().R0_1)
{
if(DEBUG)
{
G.v().out.println("*** R->BOOLEAN *** " + var);
}
var.union(BOOLEAN);
modified = true;
}
}
}
}
}
private void assign_types_1() throws TypeException
{
for( Iterator localIt = stmtBody.getLocals().iterator(); localIt.hasNext(); ) {
final Local local = (Local) localIt.next();
if(local.getType() instanceof IntegerType)
{
TypeVariable var = typeVariable(local);
if(var.type() == null || var.type().type() == null)
{
TypeVariable.error("Type Error(21): Variable without type");
}
else
{
local.setType(var.type().type());
}
if(DEBUG)
{
if((var != null) &&
(var.approx() != null) &&
(var.approx().type() != null) &&
(local != null) &&
(local.getType() != null) &&
!local.getType().equals(var.approx().type()))
{
G.v().out.println("local: " + local + ", type: " + local.getType() + ", approx: " + var.approx().type());
}
}
}
}
}
private void assign_types_2() throws TypeException
{
for( Iterator localIt = stmtBody.getLocals().iterator(); localIt.hasNext(); ) {
final Local local = (Local) localIt.next();
if(local.getType() instanceof IntegerType)
{
TypeVariable var = typeVariable(local);
if(var.inv_approx() != null && var.inv_approx().type() != null)
{
local.setType(var.inv_approx().type());
}
else if(var.approx().type() != null)
{
local.setType(var.approx().type());
}
else if(var.approx() == ClassHierarchy.v().R0_1)
{
local.setType(BooleanType.v());
}
else if(var.approx() == ClassHierarchy.v().R0_127)
{
local.setType(ByteType.v());
}
else
{
local.setType(ShortType.v());
}
}
}
}
private void check_constraints() throws TypeException
{
ConstraintChecker checker = new ConstraintChecker(this, false);
StringBuffer s = null;
if(DEBUG)
{
s = new StringBuffer("Checking:\n");
}
for( Iterator stmtIt = stmtBody.getUnits().iterator(); stmtIt.hasNext(); ) {
final Stmt stmt = (Stmt) stmtIt.next();
if(DEBUG)
{
s.append(" " + stmt + "\n");
}
try
{
checker.check(stmt, stmtBody);
}
catch(TypeException e)
{
if(DEBUG)
{
G.v().out.println(s);
}
throw e;
}
}
}
private void check_and_fix_constraints() throws TypeException
{
ConstraintChecker checker = new ConstraintChecker(this, true);
StringBuffer s = null;
PatchingChain units = stmtBody.getUnits();
Stmt[] stmts = new Stmt[units.size()];
units.toArray(stmts);
if(DEBUG)
{
s = new StringBuffer("Checking:\n");
}
for (Stmt stmt : stmts) {
if(DEBUG)
{
s.append(" " + stmt + "\n");
}
try
{
checker.check(stmt, stmtBody);
}
catch(TypeException e)
{
if(DEBUG)
{
G.v().out.println(s);
}
throw e;
}
}
}
private void compute_approximate_types() throws TypeException
{
TreeSet<TypeVariable> workList = new TreeSet<TypeVariable>();
for (TypeVariable var : typeVariableList) {
if(var.type() != null)
{
workList.add(var);
}
}
TypeVariable.computeApprox(workList);
workList = new TreeSet<TypeVariable>();
for (TypeVariable var : typeVariableList) {
if(var.type() != null)
{
workList.add(var);
}
}
TypeVariable.computeInvApprox(workList);
for (TypeVariable var : typeVariableList) {
if (var.approx() == null)
{
var.union(INT);
}
}
}
private void compute_solved()
{
Set<TypeVariable> unsolved_set = new TreeSet<TypeVariable>();
Set<TypeVariable> solved_set = new TreeSet<TypeVariable>();
for (TypeVariable var : typeVariableList) {
if(var.type() == null)
{
unsolved_set.add(var);
}
else
{
solved_set.add(var);
}
}
solved = new LinkedList<TypeVariable>(solved_set);
unsolved = new LinkedList<TypeVariable>(unsolved_set);
}
private void refresh_solved() throws TypeException
{
Set<TypeVariable> unsolved_set = new TreeSet<TypeVariable>();
Set<TypeVariable> solved_set = new TreeSet<TypeVariable>(solved);
for (TypeVariable var : unsolved) {
if(var.type() == null)
{
unsolved_set.add(var);
}
else
{
solved_set.add(var);
}
}
solved = new LinkedList<TypeVariable>(solved_set);
unsolved = new LinkedList<TypeVariable>(unsolved_set);
}
}