@Override
public void visit(BinaryExpr expr) {
switch (expr.getOperation()) {
case AND:
case OR:
resultExpr = expr;
return;
default:
break;
}
expr.getSecondOperand().acceptVisitor(this);
Expr b = resultExpr;
if (b instanceof ConstantExpr && expr.getOperation() == BinaryOperation.SUBTRACT) {
if (tryMakePositive((ConstantExpr) b)) {
expr.setOperation(BinaryOperation.ADD);
}
}
expr.getFirstOperand().acceptVisitor(this);
Expr a = resultExpr;
Expr p = a;
Expr q = b;
boolean invert = false;
if (isZero(p)) {
Expr tmp = p;
p = q;
q = tmp;
invert = true;
}
if (isComparison(p) && isZero(q)) {
switch (expr.getOperation()) {
case EQUALS:
case NOT_EQUALS:
case LESS:
case LESS_OR_EQUALS:
case GREATER:
case GREATER_OR_EQUALS:
{
BinaryExpr comparison = (BinaryExpr) p;
Expr result =
BinaryExpr.binary(
expr.getOperation(),
comparison.getFirstOperand(),
comparison.getSecondOperand());
result.setLocation(comparison.getLocation());
if (invert) {
result = ExprOptimizer.invert(result);
}
resultExpr = result;
return;
}
default:
break;
}
}
expr.setFirstOperand(a);
expr.setSecondOperand(b);
resultExpr = expr;
}
@Override
public void visit(WhileStatement statement) {
if (statement.getBody().size() == 1 && statement.getBody().get(0) instanceof WhileStatement) {
WhileStatement innerLoop = (WhileStatement) statement.getBody().get(0);
BreakToContinueReplacer replacer = new BreakToContinueReplacer(innerLoop, statement);
replacer.visitSequence(innerLoop.getBody());
statement.getBody().clear();
statement.getBody().addAll(innerLoop.getBody());
}
List<Statement> statements = processSequence(statement.getBody());
for (int i = 0; i < statements.size(); ++i) {
if (statements.get(i) instanceof ContinueStatement) {
ContinueStatement continueStmt = (ContinueStatement) statements.get(i);
if (continueStmt.getTarget() == statement) {
statements.subList(i, statements.size()).clear();
break;
}
}
}
statement.getBody().clear();
statement.getBody().addAll(statements);
if (statement.getCondition() != null) {
List<Statement> sequenceBackup = resultSequence;
resultSequence = new ArrayList<>();
statement.getCondition().acceptVisitor(this);
statement.setCondition(resultExpr);
resultSequence = sequenceBackup;
}
while (true) {
if (!statement.getBody().isEmpty()
&& statement.getBody().get(0) instanceof ConditionalStatement) {
ConditionalStatement cond = (ConditionalStatement) statement.getBody().get(0);
if (cond.getConsequent().size() == 1
&& cond.getConsequent().get(0) instanceof BreakStatement) {
BreakStatement breakStmt = (BreakStatement) cond.getConsequent().get(0);
if (breakStmt.getTarget() == statement) {
statement.getBody().remove(0);
if (statement.getCondition() != null) {
Expr newCondition =
Expr.binary(
BinaryOperation.AND,
statement.getCondition(),
ExprOptimizer.invert(cond.getCondition()));
newCondition.setLocation(statement.getCondition().getLocation());
statement.setCondition(newCondition);
} else {
statement.setCondition(ExprOptimizer.invert(cond.getCondition()));
}
continue;
}
}
}
break;
}
resultStmt = statement;
}
private Expr compare(BinaryOperation op, Variable value) {
Expr expr = Expr.binary(op, Expr.var(value.getIndex()), Expr.constant(0));
expr.setLocation(currentLocation);
return expr;
}
private Expr withLocation(Expr expr) {
expr.setLocation(currentLocation);
return expr;
}