public void BuildLabelGroups(JSFunctionExpression function)
{
// If a label is applied to the first statement in a block, hoist it upward
// onto the parent block.
var lh = new LabelHoister();
do
{
lh.HoistedALabel = false;
lh.Visit(function);
} while (lh.HoistedALabel);
// Walk the function to build our list of labels and gotos.
Visit(function);
// When a goto crosses block boundaries, we need to move the target label
// upwards so that the goto can reach it.
foreach (var g in Gotos)
{
var targetLabel = Labels[g.TargetLabel];
if (targetLabel.EnclosingBlock.Depth > g.EnclosingBlock.Depth)
{
targetLabel.EnclosingBlock = g.EnclosingBlock;
}
}
foreach (var l in Labels.Values)
{
l.EnsureLabelGroupExists(LabelGroups);
var replacementGoto = new JSExpressionStatement(
new JSGotoExpression(l.LabelledStatement.Label)
);
l.EnclosingBlock.Block.ReplaceChildRecursive(l.LabelledStatement, replacementGoto);
l.LabelGroup.Add(l.LabelledStatement);
}
// If a label group only contains one label (plus an entry label),
// and it has a parent label group, hoist the label up.
var lgs = new LabelGroupFlattener();
do
{
lgs.FlattenedAGroup = false;
lgs.Visit(function);
} while (lgs.FlattenedAGroup);
// Remove any labels within a label group that contain no statements (as long
// as no goto targets that label directly). This will prune empty entry/exit labels.
var elr = new EmptyLabelRemover(UsedLabels);
elr.Visit(function);
}
public void BuildLabelGroups(JSFunctionExpression function)
{
// If a label is applied to the first statement in a block, hoist it upward
// onto the parent block.
var lh = new LabelHoister();
do {
lh.HoistedALabel = false;
lh.Visit(function);
} while (lh.HoistedALabel);
// Walk the function to build our list of labels and gotos.
Visit(function);
// When a goto crosses block boundaries, we need to move the target label
// upwards so that the goto can reach it.
foreach (var g in Gotos) {
var targetLabel = Labels[g.TargetLabel];
if (targetLabel.EnclosingBlock.Depth > g.EnclosingBlock.Depth)
targetLabel.EnclosingBlock = g.EnclosingBlock;
}
foreach (var l in Labels.Values) {
l.EnsureLabelGroupExists(LabelGroups);
var replacementGoto = new JSExpressionStatement(
new JSGotoExpression(l.LabelledStatement.Label)
);
l.EnclosingBlock.Block.ReplaceChildRecursive(l.LabelledStatement, replacementGoto);
l.LabelGroup.Add(l.LabelledStatement);
}
// If a label group only contains one label (plus an entry label),
// and it has a parent label group, hoist the label up.
var lgs = new LabelGroupFlattener();
do {
lgs.FlattenedAGroup = false;
lgs.Visit(function);
} while (lgs.FlattenedAGroup);
// Remove any labels within a label group that contain no statements (as long
// as no goto targets that label directly). This will prune empty entry/exit labels.
var elr = new EmptyLabelRemover(UsedLabels);
elr.Visit(function);
}