@Nullable
private DfaInstructionState[] handleRelationBinop(
BinopInstruction instruction,
DataFlowRunner runner,
DfaMemoryState memState,
DfaValue dfaRight,
DfaValue dfaLeft) {
DfaValueFactory factory = runner.getFactory();
final Instruction next = runner.getInstruction(instruction.getIndex() + 1);
DfaRelationValue dfaRelation =
factory
.getRelationFactory()
.createRelation(dfaLeft, dfaRight, instruction.getOperationSign(), false);
if (dfaRelation == null) {
return null;
}
myCanBeNullInInstanceof.add(instruction);
ArrayList<DfaInstructionState> states = new ArrayList<DfaInstructionState>();
final DfaMemoryState trueCopy = memState.createCopy();
if (trueCopy.applyCondition(dfaRelation)) {
trueCopy.push(factory.getConstFactory().getTrue());
instruction.setTrueReachable();
states.add(new DfaInstructionState(next, trueCopy));
}
//noinspection UnnecessaryLocalVariable
DfaMemoryState falseCopy = memState;
if (falseCopy.applyCondition(dfaRelation.createNegated())) {
falseCopy.push(factory.getConstFactory().getFalse());
instruction.setFalseReachable();
states.add(new DfaInstructionState(next, falseCopy));
if (instruction instanceof InstanceofInstruction && !falseCopy.isNull(dfaLeft)) {
myUsefulInstanceofs.add((InstanceofInstruction) instruction);
}
}
return states.toArray(new DfaInstructionState[states.size()]);
}
@Override
public DfaInstructionState[] visitBinop(
BinopInstruction instruction, DataFlowRunner runner, DfaMemoryState memState) {
myReachable.add(instruction);
DfaValue dfaRight = memState.pop();
DfaValue dfaLeft = memState.pop();
final IElementType opSign = instruction.getOperationSign();
if (opSign != null) {
DfaInstructionState[] states =
handleConstantComparison(instruction, runner, memState, dfaRight, dfaLeft, opSign);
if (states == null) {
states = handleRelationBinop(instruction, runner, memState, dfaRight, dfaLeft);
}
if (states != null) {
return states;
}
if (PLUS == opSign) {
memState.push(instruction.getNonNullStringValue(runner.getFactory()));
} else {
if (instruction instanceof InstanceofInstruction) {
handleInstanceof((InstanceofInstruction) instruction, dfaRight, dfaLeft);
}
memState.push(DfaUnknownValue.getInstance());
}
} else {
memState.push(DfaUnknownValue.getInstance());
}
instruction.setTrueReachable(); // Not a branching instruction actually.
instruction.setFalseReachable();
return nextInstruction(instruction, runner, memState);
}