/*******************************************************************************
* Copyright (c) 2008 IBM Corporation.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package com.ibm.wala.analysis.reflection;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import com.ibm.wala.cfg.ControlFlowGraph;
import com.ibm.wala.cfg.InducedCFG;
import com.ibm.wala.classLoader.CallSiteReference;
import com.ibm.wala.classLoader.IClass;
import com.ibm.wala.classLoader.IMethod;
import com.ibm.wala.classLoader.NewSiteReference;
import com.ibm.wala.ipa.callgraph.CGNode;
import com.ibm.wala.ipa.callgraph.propagation.SSAContextInterpreter;
import com.ibm.wala.ipa.summaries.SyntheticIR;
import com.ibm.wala.ssa.ConstantValue;
import com.ibm.wala.ssa.DefUse;
import com.ibm.wala.ssa.IR;
import com.ibm.wala.ssa.ISSABasicBlock;
import com.ibm.wala.ssa.SSAArrayStoreInstruction;
import com.ibm.wala.ssa.SSAInstruction;
import com.ibm.wala.ssa.SSAInstructionFactory;
import com.ibm.wala.ssa.SSANewInstruction;
import com.ibm.wala.ssa.SSAOptions;
import com.ibm.wala.ssa.SSAReturnInstruction;
import com.ibm.wala.types.FieldReference;
import com.ibm.wala.types.MethodReference;
import com.ibm.wala.types.TypeReference;
import com.ibm.wala.util.collections.EmptyIterator;
import com.ibm.wala.util.collections.HashMapFactory;
import com.ibm.wala.util.collections.HashSetFactory;
import com.ibm.wala.util.collections.NonNullSingletonIterator;
import com.ibm.wala.util.debug.Assertions;
/**
* An {@link SSAContextInterpreter} specialized to interpret methods on java.lang.Class in a {@link JavaTypeContext} which
* represents the point-type of the class object created by the call.
*
* Currently supported methods:
* <ul>
* <li>getConstructor
* <li>getConstructors
* <li>getMethod
* <li>getMethods
* <li>getDeclaredConstructor
* <li>getDeclaredConstructors
* <li>getDeclaredMethod
* <li>getDeclaredMethods
* </ul>
*/
public class JavaLangClassContextInterpreter implements SSAContextInterpreter {
public final static MethodReference GET_CONSTRUCTOR = MethodReference.findOrCreate(TypeReference.JavaLangClass, "getConstructor",
"([Ljava/lang/Class;)Ljava/lang/reflect/Constructor;");
public final static MethodReference GET_CONSTRUCTORS = MethodReference.findOrCreate(TypeReference.JavaLangClass,
"getConstructors", "()[Ljava/lang/reflect/Constructor;");
public final static MethodReference GET_METHOD = MethodReference.findOrCreate(TypeReference.JavaLangClass, "getMethod",
"(Ljava/lang/String;[Ljava/lang/Class;)Ljava/lang/reflect/Method;");
public final static MethodReference GET_METHODS = MethodReference.findOrCreate(TypeReference.JavaLangClass, "getMethods",
"()[Ljava/lang/reflect/Method;");
public final static MethodReference GET_DECLARED_CONSTRUCTOR = MethodReference.findOrCreate(TypeReference.JavaLangClass,
"getDeclaredConstructor", "([Ljava/lang/Class;)Ljava/lang/reflect/Constructor;");
public final static MethodReference GET_DECLARED_CONSTRUCTORS = MethodReference.findOrCreate(TypeReference.JavaLangClass,
"getDeclaredConstructors", "()[Ljava/lang/reflect/Constructor;");
public final static MethodReference GET_DECLARED_METHOD = MethodReference.findOrCreate(TypeReference.JavaLangClass,
"getDeclaredMethod", "(Ljava/lang/String;[Ljava/lang/Class;)Ljava/lang/reflect/Method;");
public final static MethodReference GET_DECLARED_METHODS = MethodReference.findOrCreate(TypeReference.JavaLangClass,
"getDeclaredMethods", "()[Ljava/lang/reflect/Method;");
private static final boolean DEBUG = false;
/** BEGIN Custom change: caching */
private final Map<String, IR> cache = HashMapFactory.make();
/** END Custom change: caching */
/*
* @see com.ibm.wala.ipa.callgraph.propagation.SSAContextInterpreter#getIR(com.ibm.wala.ipa.callgraph.CGNode)
*/
@Override
public IR getIR(CGNode node) {
if (node == null) {
throw new IllegalArgumentException("node is null");
}
assert understands(node);
if (DEBUG) {
System.err.println("generating IR for " + node);
}
/** BEGIN Custom change: caching */
final JavaTypeContext context = (JavaTypeContext) node.getContext();
final IMethod method = node.getMethod();
final String hashKey = method.toString() + "@" + context.toString();
IR result = cache.get(hashKey);
if (result == null) {
result = makeIR(method, context);
if (result == null) {
Assertions.UNREACHABLE("Unexpected method " + node);
}
cache.put(hashKey, result);
}
return result;
}
private IR makeIR(IMethod method, JavaTypeContext context) {
Map<Integer, ConstantValue> constants = HashMapFactory.make();
if (method.getReference().equals(GET_CONSTRUCTOR)) {
SSAInstruction instrs[] = makeGetCtorStatements(context, constants);
return new SyntheticIR(method, context, new InducedCFG(instrs, method, context), instrs, SSAOptions.defaultOptions(),
constants);
}
if (method.getReference().equals(GET_CONSTRUCTORS)) {
SSAInstruction instrs[] = makeGetCtorsStatements(context, constants);
return new SyntheticIR(method, context, new InducedCFG(instrs, method, context), instrs, SSAOptions.defaultOptions(),
constants);
}
if (method.getReference().equals(GET_METHOD)) {
SSAInstruction instrs[] = makeGetMethodStatements(context, constants);
return new SyntheticIR(method, context, new InducedCFG(instrs, method, context), instrs, SSAOptions.defaultOptions(),
constants);
}
if (method.getReference().equals(GET_METHODS)) {
SSAInstruction instrs[] = makeGetMethodsStatments(context, constants);
return new SyntheticIR(method, context, new InducedCFG(instrs, method, context), instrs, SSAOptions.defaultOptions(),
constants);
}
if (method.getReference().equals(GET_DECLARED_CONSTRUCTOR)) {
SSAInstruction instrs[] = makeGetDeclCtorStatements(context, constants);
return new SyntheticIR(method, context, new InducedCFG(instrs, method, context), instrs, SSAOptions.defaultOptions(),
constants);
}
if (method.getReference().equals(GET_DECLARED_CONSTRUCTORS)) {
SSAInstruction instrs[] = makeGetDeclCtorsStatements(context, constants);
return new SyntheticIR(method, context, new InducedCFG(instrs, method, context), instrs, SSAOptions.defaultOptions(),
constants);
}
if (method.getReference().equals(GET_DECLARED_METHOD)) {
SSAInstruction instrs[] = makeGetDeclaredMethodStatements(context, constants);
return new SyntheticIR(method, context, new InducedCFG(instrs, method, context), instrs, SSAOptions.defaultOptions(),
constants);
}
if (method.getReference().equals(GET_DECLARED_METHODS)) {
SSAInstruction instrs[] = makeGetDeclaredMethodsStatements(context, constants);
return new SyntheticIR(method, context, new InducedCFG(instrs, method, context), instrs, SSAOptions.defaultOptions(),
constants);
}
Assertions.UNREACHABLE("Unexpected method " + method);
return null;
}
/** END Custom change: caching */
/*
* @see com.ibm.wala.ipa.callgraph.propagation.SSAContextInterpreter#getNumberOfStatements(com.ibm.wala.ipa.callgraph.CGNode)
*/
@Override
public int getNumberOfStatements(CGNode node) {
assert understands(node);
return getIR(node).getInstructions().length;
}
/*
* @see com.ibm.wala.ipa.callgraph.propagation.rta.RTAContextInterpreter#understands(com.ibm.wala.ipa.callgraph.CGNode)
*/
@Override
public boolean understands(CGNode node) {
if (node == null) {
throw new IllegalArgumentException("node is null");
}
if (!(node.getContext() instanceof JavaTypeContext)) {
return false;
}
MethodReference mRef = node.getMethod().getReference();
return mRef.equals(GET_CONSTRUCTOR) || mRef.equals(GET_CONSTRUCTORS) || mRef.equals(GET_METHOD) || mRef.equals(GET_METHODS)
|| mRef.equals(GET_DECLARED_CONSTRUCTOR) || mRef.equals(GET_DECLARED_CONSTRUCTORS) || mRef.equals(GET_DECLARED_METHOD)
|| mRef.equals(GET_DECLARED_METHODS);
}
@Override
public Iterator<NewSiteReference> iterateNewSites(CGNode node) {
if (node == null) {
throw new IllegalArgumentException("node is null");
}
assert understands(node);
JavaTypeContext context = (JavaTypeContext) node.getContext();
TypeReference tr = context.getType().getTypeReference();
if (tr != null) {
return new NonNullSingletonIterator<NewSiteReference>(NewSiteReference.make(0, tr));
}
return EmptyIterator.instance();
}
@Override
public Iterator<CallSiteReference> iterateCallSites(CGNode node) {
assert understands(node);
return EmptyIterator.instance();
}
/**
* Get all non-constructor, non-class-initializer methods declared by a class
*/
private Collection<IMethod> getDeclaredNormalMethods(IClass cls) {
Collection<IMethod> result = HashSetFactory.make();
for (IMethod m : cls.getDeclaredMethods()) {
if (!m.isInit() && !m.isClinit()) {
result.add(m);
}
}
return result;
}
/**
* Get all non-constructor, non-class-initializer methods declared by a class and all its superclasses
*/
private Collection<IMethod> getAllNormalPublicMethods(IClass cls) {
Collection<IMethod> result = HashSetFactory.make();
Collection<IMethod> allMethods = null;
allMethods = cls.getAllMethods();
for (IMethod m : allMethods) {
if (!m.isInit() && !m.isClinit() && m.isPublic()) {
result.add(m);
}
}
return result;
}
/**
* Get all the constructors of a class
*/
private Collection<IMethod> getConstructors(IClass cls) {
Collection<IMethod> result = HashSetFactory.make();
for (IMethod m : cls.getDeclaredMethods()) {
if (m.isInit()) {
result.add(m);
}
}
return result;
}
/**
* Get all the public constructors of a class
*/
private Collection<IMethod> getPublicConstructors(IClass cls) {
Collection<IMethod> result = HashSetFactory.make();
for (IMethod m : cls.getDeclaredMethods()) {
if (m.isInit() && m.isPublic()) {
result.add(m);
}
}
return result;
}
/**
* create statements for methods like getConstructors() and getMethods(), which return an array of methods.
*
* @param returnValues the possible return values for this method.
*/
private SSAInstruction[] getMethodArrayStatements(MethodReference ref, Collection<IMethod> returnValues, JavaTypeContext context,
Map<Integer, ConstantValue> constants) {
ArrayList<SSAInstruction> statements = new ArrayList<SSAInstruction>();
int nextLocal = ref.getNumberOfParameters() + 2;
int retValue = nextLocal++;
IClass cls = context.getType().getType();
SSAInstructionFactory insts = context.getType().getType().getClassLoader().getInstructionFactory();
if (cls != null) {
TypeReference arrType = ref.getReturnType();
NewSiteReference site = new NewSiteReference(retValue, arrType);
int sizeVn = nextLocal++;
constants.put(sizeVn, new ConstantValue(returnValues.size()));
SSANewInstruction allocArr = insts.NewInstruction(statements.size(), retValue, site, new int[] { sizeVn });
statements.add(allocArr);
int i = 0;
for (IMethod m : returnValues) {
int c = nextLocal++;
constants.put(c, new ConstantValue(m));
int index = i++;
int indexVn = nextLocal++;
constants.put(indexVn, new ConstantValue(index));
SSAArrayStoreInstruction store = insts
.ArrayStoreInstruction(statements.size(), retValue, indexVn, c, TypeReference.JavaLangReflectConstructor);
statements.add(store);
}
SSAReturnInstruction R = insts.ReturnInstruction(statements.size(), retValue, false);
statements.add(R);
} else {
// SJF: This is incorrect. TODO: fix and enable.
// SSAThrowInstruction t = insts.ThrowInstruction(retValue);
// statements.add(t);
}
SSAInstruction[] result = new SSAInstruction[statements.size()];
Iterator<SSAInstruction> it = statements.iterator();
for (int i = 0; i < result.length; i++) {
result[i] = it.next();
}
return result;
}
/**
* create statements for methods like getConstructor() and getDeclaredMethod(), which return a single method. This creates a
* return statement for each possible return value, each of which is a {@link ConstantValue} for an {@link IMethod}.
*
* @param returnValues the possible return values for this method.
*/
private SSAInstruction[] getParticularMethodStatements(MethodReference ref, Collection<IMethod> returnValues,
JavaTypeContext context, Map<Integer, ConstantValue> constants) {
ArrayList<SSAInstruction> statements = new ArrayList<SSAInstruction>();
int nextLocal = ref.getNumberOfParameters() + 2;
IClass cls = context.getType().getType();
SSAInstructionFactory insts = context.getType().getType().getClassLoader().getInstructionFactory();
if (cls != null) {
for (IMethod m : returnValues) {
int c = nextLocal++;
constants.put(c, new ConstantValue(m));
SSAReturnInstruction R = insts.ReturnInstruction(statements.size(), c, false);
statements.add(R);
}
} else {
// SJF: This is incorrect. TODO: fix and enable.
// SSAThrowInstruction t = insts.ThrowInstruction(retValue);
// statements.add(t);
}
SSAInstruction[] result = new SSAInstruction[statements.size()];
Iterator<SSAInstruction> it = statements.iterator();
for (int i = 0; i < result.length; i++) {
result[i] = it.next();
}
return result;
}
/**
* create statements for getConstructor()
*/
private SSAInstruction[] makeGetCtorStatements(JavaTypeContext context, Map<Integer, ConstantValue> constants) {
IClass cls = context.getType().getType();
if (cls == null) {
return getParticularMethodStatements(GET_CONSTRUCTOR, null, context, constants);
} else {
return getParticularMethodStatements(GET_CONSTRUCTOR, getPublicConstructors(cls), context, constants);
}
}
// TODO
private SSAInstruction[] makeGetCtorsStatements(JavaTypeContext context, Map<Integer, ConstantValue> constants) {
IClass cls = context.getType().getType();
if (cls == null) {
return getMethodArrayStatements(GET_DECLARED_CONSTRUCTORS, null, context, constants);
} else {
return getMethodArrayStatements(GET_DECLARED_CONSTRUCTORS, getPublicConstructors(cls), context, constants);
}
}
private SSAInstruction[] makeGetMethodStatements(JavaTypeContext context, Map<Integer, ConstantValue> constants) {
IClass cls = context.getType().getType();
if (cls == null) {
return getParticularMethodStatements(GET_METHOD, null, context, constants);
} else {
return getParticularMethodStatements(GET_METHOD, getAllNormalPublicMethods(cls), context, constants);
}
}
private SSAInstruction[] makeGetMethodsStatments(JavaTypeContext context, Map<Integer, ConstantValue> constants) {
IClass cls = context.getType().getType();
if (cls == null) {
return getMethodArrayStatements(GET_METHODS, null, context, constants);
} else {
return getMethodArrayStatements(GET_METHODS, getAllNormalPublicMethods(cls), context, constants);
}
}
/**
* create statements for getConstructor()
*/
private SSAInstruction[] makeGetDeclCtorStatements(JavaTypeContext context, Map<Integer, ConstantValue> constants) {
IClass cls = context.getType().getType();
if (cls == null) {
return getParticularMethodStatements(GET_DECLARED_CONSTRUCTOR, null, context, constants);
} else {
return getParticularMethodStatements(GET_DECLARED_CONSTRUCTOR, getConstructors(cls), context, constants);
}
}
private SSAInstruction[] makeGetDeclCtorsStatements(JavaTypeContext context, Map<Integer, ConstantValue> constants) {
IClass cls = context.getType().getType();
if (cls == null) {
return getMethodArrayStatements(GET_DECLARED_CONSTRUCTORS, null, context, constants);
} else {
return getMethodArrayStatements(GET_DECLARED_CONSTRUCTORS, getConstructors(cls), context, constants);
}
}
/**
* create statements for getDeclaredMethod()
*/
private SSAInstruction[] makeGetDeclaredMethodStatements(JavaTypeContext context, Map<Integer, ConstantValue> constants) {
IClass cls = context.getType().getType();
if (cls == null) {
return getParticularMethodStatements(GET_DECLARED_METHOD, null, context, constants);
} else {
return getParticularMethodStatements(GET_DECLARED_METHOD, getDeclaredNormalMethods(cls), context, constants);
}
}
/**
* create statements for getDeclaredMethod()
*/
private SSAInstruction[] makeGetDeclaredMethodsStatements(JavaTypeContext context, Map<Integer, ConstantValue> constants) {
IClass cls = context.getType().getType();
if (cls == null) {
return getMethodArrayStatements(GET_DECLARED_METHODS, null, context, constants);
} else {
return getMethodArrayStatements(GET_DECLARED_METHODS, getDeclaredNormalMethods(cls), context, constants);
}
}
@Override
public boolean recordFactoryType(CGNode node, IClass klass) {
return false;
}
@Override
public Iterator<FieldReference> iterateFieldsRead(CGNode node) {
return EmptyIterator.instance();
}
@Override
public Iterator<FieldReference> iterateFieldsWritten(CGNode node) {
return EmptyIterator.instance();
}
@Override
public ControlFlowGraph<SSAInstruction, ISSABasicBlock> getCFG(CGNode N) {
return getIR(N).getControlFlowGraph();
}
@Override
public DefUse getDU(CGNode node) {
return new DefUse(getIR(node));
}
}