public void VisitNode(JSExpressionStatement es)
{
try {
VisitChildren(es);
} catch (Exception exc) {
Console.WriteLine("// Error in statement");
Console.WriteLine("// {0}", es);
throw;
}
}
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 VisitNode(JSExpressionStatement es)
{
var invocationExpression = es.Expression as JSInvocationExpression;
if (invocationExpression != null)
{
var replacement = MaybeReplaceInvocation(invocationExpression);
if (replacement != null)
{
ParentNode.ReplaceChild(es, replacement);
VisitReplacement(replacement);
return;
}
}
VisitChildren(es);
}
public void VisitNode(JSExpressionStatement statement)
{
bool isNull = (statement.IsNull ||
statement.Expression.IsNull) &&
!(statement.Expression is JSUntranslatableExpression) &&
!(statement.Expression is JSIgnoredMemberReference);
Visit(statement.Expression);
if (!isNull &&
((BlockStack.Count == 0) ||
(BlockStack.Peek() != BlockType.ForHeader))
)
{
Output.Semicolon();
}
}
public void BuildLabelGroups()
{
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);
}
}
protected void TransformVariableIntoReference(JSVariable variable, JSVariableDeclarationStatement statement, int declarationIndex, JSBlockStatement enclosingBlock)
{
var oldDeclaration = statement.Declarations[declarationIndex];
var valueType = oldDeclaration.Right.GetActualType(JSIL.TypeSystem);
var newVariable = variable.Reference();
var enclosingFunction = Stack.OfType <JSFunctionExpression>().First();
JSExpression initialValue;
// If the declaration was in function scope originally we can hoist the initial value
// into our new variable declaration. If not, we need to initialize the ref variable
// to the default value for its type. It will get the correct value assigned later.
if (enclosingBlock == enclosingFunction.Body)
{
initialValue = oldDeclaration.Right;
}
else
{
initialValue = new JSDefaultValueLiteral(valueType);
}
var newDeclaration = new JSVariableDeclarationStatement(new JSBinaryOperatorExpression(
JSOperator.Assignment,
// We have to use a constructed ref to the variable here, otherwise
// the declaration will look like 'var x.value = foo'
new JSVariable(variable.Identifier, variable.IdentifierType, variable.Function),
JSIL.NewReference(initialValue),
newVariable.IdentifierType
));
if (Tracing)
{
Console.WriteLine(String.Format("Transformed {0} into {1} in {2}", variable, newVariable, statement));
}
// Insert the new declaration directly before the top-level block containing the original
// declaration. This ensures that if its initial value has a dependency on external state,
// the declaration will not precede the values it depends on.
// Note that for declarations that were hoisted out of inner blocks (conditionals, loops)
// it doesn't actually matter where the insert occurs, since we initialize with a default
// value in that case.
enclosingFunction.Body.InsertNearChildRecursive(
statement, newDeclaration, 0
);
// If the reference is being declared in function scope, it doesn't need a separate assignment
// for its initialization. Otherwise, we need to insert an assignment after the original variable
// declaration statement to ensure that the reference variable is initialized to the right value
// at the exact right point in the function's execution.
if (enclosingBlock != enclosingFunction.Body)
{
var newAssignment = new JSExpressionStatement(
new JSBinaryOperatorExpression(
JSOperator.Assignment, newVariable, oldDeclaration.Right, valueType
)
);
var insertLocation = enclosingBlock.Statements.IndexOf(statement) + 1;
enclosingBlock.Statements.Insert(insertLocation, newAssignment);
}
Variables[variable.Identifier] = newVariable;
statement.Declarations.RemoveAt(declarationIndex);
TransformedVariables.Add(variable.Identifier);
}
public void VisitNode(JSExpressionStatement es)
{
base.VisitNode(es);
}
