/*
* Copyright 2000-2017 JetBrains s.r.o.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jetbrains.java.decompiler.modules.decompiler.vars;
import org.jetbrains.java.decompiler.code.CodeConstants;
import org.jetbrains.java.decompiler.main.DecompilerContext;
import org.jetbrains.java.decompiler.modules.decompiler.exps.*;
import org.jetbrains.java.decompiler.modules.decompiler.sforms.DirectGraph;
import org.jetbrains.java.decompiler.modules.decompiler.stats.CatchAllStatement;
import org.jetbrains.java.decompiler.modules.decompiler.stats.CatchStatement;
import org.jetbrains.java.decompiler.modules.decompiler.stats.RootStatement;
import org.jetbrains.java.decompiler.modules.decompiler.stats.Statement;
import org.jetbrains.java.decompiler.struct.StructClass;
import org.jetbrains.java.decompiler.struct.StructMethod;
import org.jetbrains.java.decompiler.struct.gen.MethodDescriptor;
import org.jetbrains.java.decompiler.struct.gen.VarType;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
public class VarTypeProcessor {
public static final int VAR_NON_FINAL = 1;
public static final int VAR_EXPLICIT_FINAL = 2;
public static final int VAR_FINAL = 3;
private final StructMethod method;
private final MethodDescriptor methodDescriptor;
private final Map<VarVersionPair, VarType> mapExprentMinTypes = new HashMap<>();
private final Map<VarVersionPair, VarType> mapExprentMaxTypes = new HashMap<>();
private final Map<VarVersionPair, Integer> mapFinalVars = new HashMap<>();
public VarTypeProcessor(StructMethod mt, MethodDescriptor md) {
method = mt;
methodDescriptor = md;
}
public void calculateVarTypes(RootStatement root, DirectGraph graph) {
setInitVars(root);
resetExprentTypes(graph);
//noinspection StatementWithEmptyBody
while (!processVarTypes(graph)) ;
}
private void setInitVars(RootStatement root) {
boolean thisVar = !method.hasModifier(CodeConstants.ACC_STATIC);
MethodDescriptor md = methodDescriptor;
if (thisVar) {
StructClass cl = (StructClass)DecompilerContext.getProperty(DecompilerContext.CURRENT_CLASS);
VarType clType = new VarType(CodeConstants.TYPE_OBJECT, 0, cl.qualifiedName);
mapExprentMinTypes.put(new VarVersionPair(0, 1), clType);
mapExprentMaxTypes.put(new VarVersionPair(0, 1), clType);
}
int varIndex = 0;
for (int i = 0; i < md.params.length; i++) {
mapExprentMinTypes.put(new VarVersionPair(varIndex + (thisVar ? 1 : 0), 1), md.params[i]);
mapExprentMaxTypes.put(new VarVersionPair(varIndex + (thisVar ? 1 : 0), 1), md.params[i]);
varIndex += md.params[i].stackSize;
}
// catch variables
LinkedList<Statement> stack = new LinkedList<>();
stack.add(root);
while (!stack.isEmpty()) {
Statement stat = stack.removeFirst();
List<VarExprent> lstVars = null;
if (stat.type == Statement.TYPE_CATCHALL) {
lstVars = ((CatchAllStatement)stat).getVars();
}
else if (stat.type == Statement.TYPE_TRYCATCH) {
lstVars = ((CatchStatement)stat).getVars();
}
if (lstVars != null) {
for (VarExprent var : lstVars) {
mapExprentMinTypes.put(new VarVersionPair(var.getIndex(), 1), var.getVarType());
mapExprentMaxTypes.put(new VarVersionPair(var.getIndex(), 1), var.getVarType());
}
}
stack.addAll(stat.getStats());
}
}
private static void resetExprentTypes(DirectGraph graph) {
graph.iterateExprents(new DirectGraph.ExprentIterator() {
@Override
public int processExprent(Exprent exprent) {
List<Exprent> lst = exprent.getAllExprents(true);
lst.add(exprent);
for (Exprent expr : lst) {
if (expr.type == Exprent.EXPRENT_VAR) {
((VarExprent)expr).setVarType(VarType.VARTYPE_UNKNOWN);
}
else if (expr.type == Exprent.EXPRENT_CONST) {
ConstExprent constExpr = (ConstExprent)expr;
if (constExpr.getConstType().typeFamily == CodeConstants.TYPE_FAMILY_INTEGER) {
constExpr.setConstType(new ConstExprent(constExpr.getIntValue(), constExpr.isBoolPermitted(), null).getConstType());
}
}
}
return 0;
}
});
}
private boolean processVarTypes(DirectGraph graph) {
return graph.iterateExprents(new DirectGraph.ExprentIterator() {
@Override
public int processExprent(Exprent exprent) {
return checkTypeExprent(exprent) ? 0 : 1;
}
});
}
private boolean checkTypeExprent(Exprent exprent) {
for (Exprent expr : exprent.getAllExprents()) {
if (!checkTypeExprent(expr)) {
return false;
}
}
if (exprent.type == Exprent.EXPRENT_CONST) {
ConstExprent constExpr = (ConstExprent)exprent;
if (constExpr.getConstType().typeFamily <= CodeConstants.TYPE_FAMILY_INTEGER) { // boolean or integer
VarVersionPair pair = new VarVersionPair(constExpr.id, -1);
if (!mapExprentMinTypes.containsKey(pair)) {
mapExprentMinTypes.put(pair, constExpr.getConstType());
}
}
}
CheckTypesResult result = exprent.checkExprTypeBounds();
boolean res = true;
if (result != null) {
for (CheckTypesResult.ExprentTypePair entry : result.getLstMaxTypeExprents()) {
if (entry.type.typeFamily != CodeConstants.TYPE_FAMILY_OBJECT) {
changeExprentType(entry.exprent, entry.type, 1);
}
}
for (CheckTypesResult.ExprentTypePair entry : result.getLstMinTypeExprents()) {
res &= changeExprentType(entry.exprent, entry.type, 0);
}
}
return res;
}
private boolean changeExprentType(Exprent exprent, VarType newType, int minMax) {
boolean res = true;
switch (exprent.type) {
case Exprent.EXPRENT_CONST:
ConstExprent constExpr = (ConstExprent)exprent;
VarType constType = constExpr.getConstType();
if (newType.typeFamily > CodeConstants.TYPE_FAMILY_INTEGER || constType.typeFamily > CodeConstants.TYPE_FAMILY_INTEGER) {
return true;
}
else if (newType.typeFamily == CodeConstants.TYPE_FAMILY_INTEGER) {
VarType minInteger = new ConstExprent((Integer)constExpr.getValue(), false, null).getConstType();
if (minInteger.isStrictSuperset(newType)) {
newType = minInteger;
}
}
case Exprent.EXPRENT_VAR:
VarVersionPair pair = null;
if (exprent.type == Exprent.EXPRENT_CONST) {
pair = new VarVersionPair(((ConstExprent)exprent).id, -1);
}
else if (exprent.type == Exprent.EXPRENT_VAR) {
//noinspection ConstantConditions
pair = new VarVersionPair((VarExprent)exprent);
}
if (minMax == 0) { // min
VarType currentMinType = mapExprentMinTypes.get(pair);
VarType newMinType;
if (currentMinType == null || newType.typeFamily > currentMinType.typeFamily) {
newMinType = newType;
}
else if (newType.typeFamily < currentMinType.typeFamily) {
return true;
}
else {
newMinType = VarType.getCommonSupertype(currentMinType, newType);
}
mapExprentMinTypes.put(pair, newMinType);
if (exprent.type == Exprent.EXPRENT_CONST) {
//noinspection ConstantConditions
((ConstExprent)exprent).setConstType(newMinType);
}
if (currentMinType != null && (newMinType.typeFamily > currentMinType.typeFamily || newMinType.isStrictSuperset(currentMinType))) {
return false;
}
}
else { // max
VarType currentMaxType = mapExprentMaxTypes.get(pair);
VarType newMaxType;
if (currentMaxType == null || newType.typeFamily < currentMaxType.typeFamily) {
newMaxType = newType;
}
else if (newType.typeFamily > currentMaxType.typeFamily) {
return true;
}
else {
newMaxType = VarType.getCommonMinType(currentMaxType, newType);
}
mapExprentMaxTypes.put(pair, newMaxType);
}
break;
case Exprent.EXPRENT_ASSIGNMENT:
return changeExprentType(((AssignmentExprent)exprent).getRight(), newType, minMax);
case Exprent.EXPRENT_FUNCTION:
FunctionExprent func = (FunctionExprent)exprent;
switch (func.getFuncType()) {
case FunctionExprent.FUNCTION_IIF: // FIXME:
res = changeExprentType(func.getLstOperands().get(1), newType, minMax) &
changeExprentType(func.getLstOperands().get(2), newType, minMax);
break;
case FunctionExprent.FUNCTION_AND:
case FunctionExprent.FUNCTION_OR:
case FunctionExprent.FUNCTION_XOR:
res = changeExprentType(func.getLstOperands().get(0), newType, minMax) &
changeExprentType(func.getLstOperands().get(1), newType, minMax);
break;
}
}
return res;
}
public Map<VarVersionPair, VarType> getMapExprentMaxTypes() {
return mapExprentMaxTypes;
}
public Map<VarVersionPair, VarType> getMapExprentMinTypes() {
return mapExprentMinTypes;
}
public Map<VarVersionPair, Integer> getMapFinalVars() {
return mapFinalVars;
}
public void setVarType(VarVersionPair pair, VarType type) {
mapExprentMinTypes.put(pair, type);
}
public VarType getVarType(VarVersionPair pair) {
return mapExprentMinTypes.get(pair);
}
}