/**
* implements the visitor to reset the stack
*
* @param obj the context object of the currently parsed code block
*/
@Override
public void visitCode(Code obj) {
stack.resetForMethodEntry(this);
super.visitCode(obj);
for (Map.Entry<Integer, CollectionRegInfo> entry : syncRegs.entrySet()) {
CollectionRegInfo cri = entry.getValue();
if (!cri.getIgnore()) {
bugReporter.reportBug(
new BugInstance(this, "LSYC_LOCAL_SYNCHRONIZED_COLLECTION", cri.getPriority())
.addClass(this)
.addMethod(this)
.addSourceLine(cri.getSourceLineAnnotation()));
}
}
}
/**
* implements the visitor to find stores to locals of synchronized collections
*
* @param seen the opcode of the currently parsed instruction
*/
@Override
public void sawOpcode(int seen) {
Integer tosIsSyncColReg = null;
try {
stack.mergeJumps(this);
if (seen == INVOKESPECIAL) {
if ("<init>".equals(getNameConstantOperand())) {
Integer minVersion = syncCtors.get(getClassConstantOperand());
if ((minVersion != null) && (classVersion >= minVersion.intValue())) {
tosIsSyncColReg = Integer.valueOf(-1);
}
}
} else if (seen == INVOKESTATIC) {
if ("java/util/Collections".equals(getClassConstantOperand())) {
if (syncMethods.contains(getNameConstantOperand())) {
tosIsSyncColReg = Integer.valueOf(-1);
}
}
} else if ((seen == ASTORE) || ((seen >= ASTORE_0) && (seen <= ASTORE_3))) {
if (stack.getStackDepth() > 0) {
OpcodeStack.Item item = stack.getStackItem(0);
int reg = RegisterUtils.getAStoreReg(this, seen);
if (item.getUserValue() != null) {
if (!syncRegs.containsKey(Integer.valueOf(reg))) {
CollectionRegInfo cri =
new CollectionRegInfo(
SourceLineAnnotation.fromVisitedInstruction(this),
RegisterUtils.getLocalVariableEndRange(
getMethod().getLocalVariableTable(), reg, getNextPC()));
syncRegs.put(Integer.valueOf(reg), cri);
}
} else {
CollectionRegInfo cri = syncRegs.get(Integer.valueOf(reg));
if (cri == null) {
cri =
new CollectionRegInfo(
RegisterUtils.getLocalVariableEndRange(
getMethod().getLocalVariableTable(), reg, getNextPC()));
syncRegs.put(Integer.valueOf(reg), cri);
}
cri.setIgnore();
}
}
} else if ((seen == ALOAD) || ((seen >= ALOAD_0) && (seen <= ALOAD_3))) {
int reg = RegisterUtils.getALoadReg(this, seen);
CollectionRegInfo cri = syncRegs.get(Integer.valueOf(reg));
if ((cri != null) && !cri.getIgnore()) tosIsSyncColReg = Integer.valueOf(reg);
} else if ((seen == PUTFIELD) || (seen == ARETURN)) {
if (stack.getStackDepth() > 0) {
OpcodeStack.Item item = stack.getStackItem(0);
syncRegs.remove(item.getUserValue());
}
}
if (syncRegs.size() > 0) {
if ((seen == INVOKESPECIAL)
|| (seen == INVOKEINTERFACE)
|| (seen == INVOKEVIRTUAL)
|| (seen == INVOKESTATIC)) {
String sig = getSigConstantOperand();
int argCount = Type.getArgumentTypes(sig).length;
if (stack.getStackDepth() >= argCount) {
for (int i = 0; i < argCount; i++) {
OpcodeStack.Item item = stack.getStackItem(i);
CollectionRegInfo cri = syncRegs.get(item.getUserValue());
if (cri != null) cri.setPriority(LOW_PRIORITY);
}
}
} else if (seen == MONITORENTER) {
// Assume if synchronized blocks are used then something tricky is going on.
// There is really no valid reason for this, other than folks who use
// synchronized blocks tend to know what's going on.
if (stack.getStackDepth() > 0) {
OpcodeStack.Item item = stack.getStackItem(0);
syncRegs.remove(item.getUserValue());
}
} else if (seen == AASTORE) {
if (stack.getStackDepth() > 0) {
OpcodeStack.Item item = stack.getStackItem(0);
syncRegs.remove(item.getUserValue());
}
}
}
int curPC = getPC();
Iterator<CollectionRegInfo> it = syncRegs.values().iterator();
while (it.hasNext()) {
CollectionRegInfo cri = it.next();
if (cri.getEndPCRange() < curPC) {
if (!cri.getIgnore()) {
bugReporter.reportBug(
new BugInstance(this, "LSYC_LOCAL_SYNCHRONIZED_COLLECTION", cri.getPriority())
.addClass(this)
.addMethod(this)
.addSourceLine(cri.getSourceLineAnnotation()));
}
it.remove();
}
}
} finally {
TernaryPatcher.pre(stack, seen);
stack.sawOpcode(this, seen);
TernaryPatcher.post(stack, seen);
if (tosIsSyncColReg != null) {
if (stack.getStackDepth() > 0) {
OpcodeStack.Item item = stack.getStackItem(0);
item.setUserValue(tosIsSyncColReg);
}
}
}
}