8013914: Removed explicit LineNumberNodes that were too brittle when code moves around, and also introduced unnecessary footprint. Introduced the Statement node and fixed dead code elimination issues that were discovered by the absense of labels for LineNumberNodes.
Reviewed-by: jlaskey, attila
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package jdk.nashorn.internal.ir;
import jdk.nashorn.internal.ir.annotations.Immutable;
import jdk.nashorn.internal.ir.visitor.NodeVisitor;
/**
* IR representation for {@code break} statements.
*/
@Immutable
public final class BreakNode extends Statement {
private final IdentNode label;
/**
* Constructor
*
* @param lineNumber line number
* @param token token
* @param finish finish
* @param label label for break or null if none
*/
public BreakNode(final int lineNumber, final long token, final int finish, final IdentNode label) {
super(lineNumber, token, finish);
this.label = label;
}
@Override
public boolean hasGoto() {
return true;
}
/**
* Assist in IR navigation.
* @param visitor IR navigating visitor.
*/
@Override
public Node accept(final NodeVisitor visitor) {
if (visitor.enterBreakNode(this)) {
return visitor.leaveBreakNode(this);
}
return this;
}
/**
* Get the label for this break node
* @return label, or null if none
*/
public IdentNode getLabel() {
return label;
}
@Override
public void toString(final StringBuilder sb) {
sb.append("break");
if (label != null) {
sb.append(' ');
label.toString(sb);
}
}
}