@Override
public void visit(VariableExpr expr) {
int index = expr.getIndex();
resultExpr = expr;
if (readFrequencies[index] != 1 || preservedVars[index]) {
return;
}
if (resultSequence.isEmpty()) {
return;
}
Statement last = resultSequence.get(resultSequence.size() - 1);
if (!(last instanceof AssignmentStatement)) {
return;
}
AssignmentStatement assignment = (AssignmentStatement) last;
if (assignment.isAsync()) {
return;
}
if (!(assignment.getLeftValue() instanceof VariableExpr)) {
return;
}
VariableExpr var = (VariableExpr) assignment.getLeftValue();
if (var.getLocation() != null
&& assignment.getLocation() != null
&& !assignment.getLocation().equals(var.getLocation())) {
return;
}
if (var.getIndex() == index) {
resultSequence.remove(resultSequence.size() - 1);
assignment.getRightValue().setLocation(assignment.getLocation());
assignment.getRightValue().acceptVisitor(this);
}
}
private void wieldTryCatch(List<Statement> statements) {
for (int i = 0; i < statements.size() - 1; ++i) {
if (statements.get(i) instanceof TryCatchStatement
&& statements.get(i + 1) instanceof TryCatchStatement) {
TryCatchStatement first = (TryCatchStatement) statements.get(i);
TryCatchStatement second = (TryCatchStatement) statements.get(i + 1);
if (Objects.equals(first.getExceptionType(), second.getExceptionType())
&& Objects.equals(first.getExceptionVariable(), second.getExceptionVariable())
&& briefStatementComparison(first.getHandler(), second.getHandler())) {
first.getProtectedBody().addAll(second.getProtectedBody());
statements.remove(i + 1);
wieldTryCatch(first.getProtectedBody());
--i;
}
}
}
}
private void eliminateRedundantBreaks(List<Statement> statements, IdentifiedStatement exit) {
if (statements.isEmpty()) {
return;
}
Statement last = statements.get(statements.size() - 1);
if (last instanceof BreakStatement && exit != null) {
IdentifiedStatement target = ((BreakStatement) last).getTarget();
if (exit == target) {
statements.remove(statements.size() - 1);
}
}
if (statements.isEmpty()) {
return;
}
for (int i = 0; i < statements.size(); ++i) {
Statement stmt = statements.get(i);
if (stmt instanceof ConditionalStatement) {
ConditionalStatement cond = (ConditionalStatement) stmt;
check_conditional:
{
last =
cond.getConsequent().isEmpty()
? null
: cond.getConsequent().get(cond.getConsequent().size() - 1);
if (last instanceof BreakStatement) {
BreakStatement breakStmt = (BreakStatement) last;
if (exit != null && exit == breakStmt.getTarget()) {
cond.getConsequent().remove(cond.getConsequent().size() - 1);
List<Statement> remaining = statements.subList(i + 1, statements.size());
cond.getAlternative().addAll(remaining);
remaining.clear();
break check_conditional;
}
}
last =
cond.getAlternative().isEmpty()
? null
: cond.getAlternative().get(cond.getAlternative().size() - 1);
if (last instanceof BreakStatement) {
BreakStatement breakStmt = (BreakStatement) last;
if (exit != null && exit == breakStmt.getTarget()) {
cond.getAlternative().remove(cond.getAlternative().size() - 1);
List<Statement> remaining = statements.subList(i + 1, statements.size());
cond.getConsequent().addAll(remaining);
remaining.clear();
}
}
}
if (i == statements.size() - 1) {
eliminateRedundantBreaks(cond.getConsequent(), exit);
eliminateRedundantBreaks(cond.getAlternative(), exit);
}
normalizeConditional(cond);
if (cond.getConsequent().size() == 1
&& cond.getConsequent().get(0) instanceof ConditionalStatement) {
ConditionalStatement innerCond = (ConditionalStatement) cond.getConsequent().get(0);
if (innerCond.getAlternative().isEmpty()) {
if (cond.getAlternative().isEmpty()) {
cond.getConsequent().clear();
cond.getConsequent().addAll(innerCond.getConsequent());
cond.setCondition(
Expr.binary(
BinaryOperation.AND,
cond.getCondition(),
innerCond.getCondition(),
cond.getCondition().getLocation()));
--i;
} else if (cond.getAlternative().size() != 1
|| !(cond.getAlternative().get(0) instanceof ConditionalStatement)) {
cond.setCondition(ExprOptimizer.invert(cond.getCondition()));
cond.getConsequent().clear();
cond.getConsequent().addAll(cond.getAlternative());
cond.getAlternative().clear();
cond.getAlternative().add(innerCond);
--i;
}
}
}
} else if (stmt instanceof BlockStatement) {
BlockStatement nestedBlock = (BlockStatement) stmt;
eliminateRedundantBreaks(nestedBlock.getBody(), nestedBlock);
} else if (stmt instanceof WhileStatement) {
WhileStatement whileStmt = (WhileStatement) stmt;
eliminateRedundantBreaks(whileStmt.getBody(), null);
} else if (stmt instanceof SwitchStatement) {
SwitchStatement switchStmt = (SwitchStatement) stmt;
for (SwitchClause clause : switchStmt.getClauses()) {
eliminateRedundantBreaks(clause.getBody(), null);
}
eliminateRedundantBreaks(switchStmt.getDefaultClause(), null);
}
}
}
