@Override
public BasicValue merge(BasicValue v, BasicValue w) {
// values are not equal
// BasicValue's equals method is too general
if ((!isTagged(v) && !w.equals(v)) || (isTagged(v) && !v.equals(w))) {
// w is a BasicValue
if (isTagged(v) && !isTagged(w)) {
return new TaggedValue(w.getType());
}
// v is a BasicValue or uninteresting and w is a interesting TaggedValue
else if ((!isTagged(v) || tagged(v).canNotContainInput())
&& isTagged(w)
&& tagged(w).canContainInput()) {
final TaggedValue taggedW = tagged(w);
if (hasImportantDependencies(taggedW) && rightMergePriority) {
// w has a merge priority, its grouped inputs will be returned
final TaggedValue returnValue = removeUngroupedInputs(taggedW.copy());
if (returnValue != null) {
return returnValue;
} else {
return new TaggedValue(v.getType());
}
}
return new TaggedValue(v.getType());
}
// v is a BasicValue and w is a uninteresting TaggedValue
else if (!isTagged(v) && isTagged(w) && tagged(w).canNotContainInput()) {
return v;
}
// merge v and w (both TaggedValues), v is interesting
else if (isTagged(v) && isTagged(w) && tagged(v).canContainInput()) {
final List<TaggedValue> list = Arrays.asList(tagged(v), tagged(w));
final TaggedValue returnValue = mergeReturnValues(list);
if (returnValue != null) {
return returnValue;
}
}
// v is a TaggedValue and uninteresting
else if (isTagged(v) && tagged(v).canNotContainInput()) {
return v;
}
// v and w are BasicValues and not equal
return BasicValue.UNINITIALIZED_VALUE;
}
// v and w are equal, return one of them
return v;
}
@Override
public BasicValue binaryOperation(AbstractInsnNode insn, BasicValue value1, BasicValue value2)
throws AnalyzerException {
switch (insn.getOpcode()) {
case PUTFIELD: // put value2 into value1
// skip untagged values
if (!isTagged(value1)) {
return null;
}
final TaggedValue taggedValue = (TaggedValue) value1;
final FieldInsnNode field = (FieldInsnNode) insn;
final boolean value2HasInputDependency = hasImportantDependencies(value2);
// if value1 is not an input, make value1 a container and add value2 to it
// PUTFIELD on inputs is not allowed
if (!taggedValue.isInput() && value2HasInputDependency) {
if (!taggedValue.canContainFields()) {
taggedValue.setTag(Tag.CONTAINER);
}
taggedValue.addContainerMapping(field.name, tagged(value2), currentFrame);
}
// if value1 is filled with non-input, make it container and mark the field
// PUTFIELD on inputs is not allowed
else if (!taggedValue.isInput() && !value2HasInputDependency) {
if (!taggedValue.canContainFields()) {
taggedValue.setTag(Tag.CONTAINER);
}
taggedValue.addContainerMapping(field.name, null, currentFrame);
}
// PUTFIELD on input leads to input modification
// make input regular
else if (taggedValue.isInput()) {
taggedValue.makeRegular();
}
return null;
default:
return super.binaryOperation(insn, value1, value2);
}
}
@SuppressWarnings({"rawtypes", "unchecked"})
@Override
public BasicValue naryOperation(AbstractInsnNode insn, List rawValues) throws AnalyzerException {
final List<BasicValue> values = (List<BasicValue>) rawValues;
boolean isStatic = false;
switch (insn.getOpcode()) {
case INVOKESTATIC:
isStatic = true;
case INVOKESPECIAL:
case INVOKEVIRTUAL:
case INVOKEINTERFACE:
final MethodInsnNode method = (MethodInsnNode) insn;
String methodOwner = method.owner;
// special case: in case that class is extending tuple we need to find the class
// that contains the actual implementation to determine the tuple size
if (method.name.equals("getField") || method.name.equals("setField")) {
try {
final String newMethodOwner =
(String) findMethodNode(methodOwner, method.name, method.desc)[1];
if (newMethodOwner.startsWith("org/apache/flink/api/java/tuple/Tuple")) {
methodOwner = newMethodOwner;
}
} catch (IllegalStateException e) {
// proceed with the known method owner
}
}
// special case: collect method of Collector
if (method.name.equals("collect")
&& methodOwner.equals("org/apache/flink/util/Collector")
&& isTagged(values.get(0))
&& tagged(values.get(0)).isCollector()) {
// check for invalid return value
if (isTagged(values.get(1)) && tagged(values.get(1)).isNull()) {
analyzer.handleNullReturn();
}
// valid return value with input dependencies
else if (hasImportantDependencies(values.get(1))) {
// add a copy and a reference
// to capture the current state and future changes in alternative paths
analyzer.getCollectorValues().add(tagged(values.get(1)));
analyzer.getCollectorValues().add(tagged(values.get(1)).copy());
}
// valid return value without input dependencies
else {
analyzer.getCollectorValues().add(null);
}
}
// special case: iterator method of Iterable
else if (method.name.equals("iterator")
&& methodOwner.equals("java/lang/Iterable")
&& isTagged(values.get(0))
&& tagged(values.get(0)).isInputIterable()) {
return new TaggedValue(
Type.getObjectType("java/util/Iterator"),
(tagged(values.get(0)).isInput1Iterable())
? Tag.INPUT_1_ITERATOR
: Tag.INPUT_2_ITERATOR);
}
// special case: hasNext method of Iterator
else if (method.name.equals("hasNext")
&& methodOwner.equals("java/util/Iterator")
&& isTagged(values.get(0))
&& tagged(values.get(0)).isInputIterator()
&& !analyzer.isUdfBinary()
&& !analyzer.isIteratorTrueAssumptionApplied()) {
return new TaggedValue(Type.BOOLEAN_TYPE, Tag.ITERATOR_TRUE_ASSUMPTION);
}
// special case: next method of Iterator
else if (method.name.equals("next")
&& methodOwner.equals("java/util/Iterator")
&& isTagged(values.get(0))
&& tagged(values.get(0)).isInputIterator()) {
// after this call it is not possible to assume "TRUE" of "hasNext()" again
analyzer.applyIteratorTrueAssumption();
if (tagged(values.get(0)).isInput1Iterator()) {
return analyzer.getInput1AsTaggedValue();
} else {
return analyzer.getInput2AsTaggedValue();
}
}
// if the UDF class contains instance variables that contain input,
// we need to analyze also methods without input-dependent arguments
// special case: do not follow the getRuntimeContext method of RichFunctions
else if (!isStatic
&& isTagged(values.get(0))
&& tagged(values.get(0)).isThis()
&& hasImportantDependencies(values.get(0))
&& !isGetRuntimeContext(method)) {
TaggedValue tv = invokeNestedMethod(values, method);
if (tv != null) {
return tv;
}
}
// the arguments have input dependencies ("THIS" does not count to the arguments)
// we can assume that method has at least one argument
else if ((!isStatic
&& isTagged(values.get(0))
&& tagged(values.get(0)).isThis()
&& hasImportantDependencies(values, true))
|| (!isStatic
&& (!isTagged(values.get(0)) || !tagged(values.get(0)).isThis())
&& hasImportantDependencies(values, false))
|| (isStatic && hasImportantDependencies(values, false))) {
// special case: Java unboxing/boxing methods on input
Type newType;
if (isTagged(values.get(0))
&& tagged(values.get(0)).isInput()
&& (!isStatic && (newType = checkForUnboxing(method.name, methodOwner)) != null
|| (isStatic
&& (newType = checkForBoxing(method.name, method.desc, methodOwner))
!= null))) {
return tagged(values.get(0)).copy(newType);
}
// special case: setField method of TupleXX
else if (method.name.equals("setField")
&& methodOwner.startsWith("org/apache/flink/api/java/tuple/Tuple")
&& isTagged(values.get(0))) {
final TaggedValue tuple = tagged(values.get(0));
tuple.setTag(Tag.CONTAINER);
// check if fieldPos is constant
// if not, we can not determine a state for the tuple
if (!isTagged(values.get(2)) || !tagged(values.get(2)).isIntConstant()) {
tuple.makeRegular();
} else {
final int constant = tagged(values.get(2)).getIntConstant();
if (constant < 0 || Integer.valueOf(methodOwner.split("Tuple")[1]) <= constant) {
analyzer.handleInvalidTupleAccess();
}
// if it is at least tagged, add it anyways
if (isTagged(values.get(1))) {
tuple.addContainerMapping("f" + constant, tagged(values.get(1)), currentFrame);
}
// mark the field as it has an undefined state
else {
tuple.addContainerMapping("f" + constant, null, currentFrame);
}
}
}
// special case: getField method of TupleXX
else if (method.name.equals("getField")
&& methodOwner.startsWith("org/apache/flink/api/java/tuple/Tuple")) {
final TaggedValue tuple =
tagged(values.get(0)); // we can assume that 0 is an input dependent tuple
// constant field index
if (isTagged(values.get(1)) // constant
&& tagged(values.get(1)).isIntConstant()) {
final int constant = tagged(values.get(1)).getIntConstant();
if (constant < 0 || Integer.valueOf(methodOwner.split("Tuple")[1]) <= constant) {
analyzer.handleInvalidTupleAccess();
}
if (tuple.containerContains("f" + constant)) {
final TaggedValue tupleField = tuple.getContainerMapping().get("f" + constant);
if (tupleField != null) {
return tupleField;
}
}
}
// unknown field index
else {
// we need to make the tuple regular as we cannot track modifications of fields
tuple.makeRegular();
return new TaggedValue(Type.getObjectType("java/lang/Object"));
}
}
// nested method invocation
else {
TaggedValue tv = invokeNestedMethod(values, method);
if (tv != null) {
return tv;
}
}
}
return super.naryOperation(insn, values);
default:
// TODO support for INVOKEDYNAMIC instructions
return super.naryOperation(insn, values);
}
}
@Override
public BasicValue unaryOperation(AbstractInsnNode insn, BasicValue value)
throws AnalyzerException {
switch (insn.getOpcode()) {
// modify jump instructions if we can assume that the hasNext operation will always
// be true at the first call
case IFEQ:
if (isTagged(value) && tagged(value).isIteratorTrueAssumption()) {
modifiedAsmAnalyzer.requestIFEQLoopModification();
}
return super.unaryOperation(insn, value);
case IFNE:
if (isTagged(value) && tagged(value).isIteratorTrueAssumption()) {
modifiedAsmAnalyzer.requestIFNELoopModification();
}
return super.unaryOperation(insn, value);
case CHECKCAST:
return value;
case PUTSTATIC:
analyzer.handlePutStatic();
return super.unaryOperation(insn, value);
case GETFIELD:
final FieldInsnNode field = (FieldInsnNode) insn;
// skip untagged values
if (!isTagged(value)) {
return super.unaryOperation(insn, value);
}
final TaggedValue taggedValue = (TaggedValue) value;
// inputs are atomic, a GETFIELD results in undefined state
if (taggedValue.isInput()) {
return super.unaryOperation(insn, value);
}
// access of input container field
// or access of a KNOWN UDF instance variable
else if (taggedValue.canContainFields() && taggedValue.containerContains(field.name)) {
final TaggedValue tv = taggedValue.getContainerMapping().get(field.name);
if (tv != null) {
return tv;
}
}
// access of a yet UNKNOWN UDF instance variable
else if (taggedValue.isThis() && !taggedValue.containerContains(field.name)) {
final TaggedValue tv = new TaggedValue(Type.getType(field.desc));
taggedValue.addContainerMapping(field.name, tv, currentFrame);
return tv;
}
// access of a yet unknown container, mark it as a container
else if (taggedValue.isRegular()) {
taggedValue.setTag(Tag.CONTAINER);
final TaggedValue tv = new TaggedValue(Type.getType(field.desc));
taggedValue.addContainerMapping(field.name, tv, currentFrame);
return tv;
}
return super.unaryOperation(insn, value);
case IINC:
// modification of a local variable or input
if (isTagged(value) && (tagged(value).isIntConstant() || tagged(value).isInput())) {
tagged(value).makeRegular();
}
return super.unaryOperation(insn, value);
default:
return super.unaryOperation(insn, value);
}
}
