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 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);
}
}
public void VisitNode(JSFunctionExpression fn)
{
Function = fn;
FirstPass = GetFirstPass(Function.Method.QualifiedIdentifier);
VisitChildren(fn);
if (ToDeclare.Count > 0) {
int i = 0;
foreach (var pd in ToDeclare) {
var es = new JSExpressionStatement(
new JSBinaryOperatorExpression(
JSOperator.Assignment, pd.Expression,
new JSDefaultValueLiteral(pd.Type),
pd.Type
));
fn.Body.Statements.Insert(i++, es);
}
}
}
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);
}
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)
Debug.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);
}
protected JSStatement TranslateStatement(ILNode node)
{
var translated = TranslateNode(node as dynamic);
var statement = translated as JSStatement;
if (statement == null) {
var expression = (JSExpression)translated;
if (expression != null)
statement = new JSExpressionStatement(expression);
else
Console.Error.WriteLine("Warning: Null statement: {0}", node);
}
return statement;
}
public void VisitNode(JSExpressionStatement node)
{
VisitChildren(node);
}
protected void TranslateTypeStaticConstructor(DecompilerContext context, JavascriptFormatter output, TypeDefinition typedef, MethodDefinition cctor, bool stubbed)
{
var typeSystem = context.CurrentModule.TypeSystem;
var fieldsToEmit =
(from f in typedef.Fields
where f.IsStatic && NeedsStaticConstructor(f.FieldType)
select f).ToArray();
// We initialize all static fields in the cctor to avoid ordering issues
Action<JSFunctionExpression> fixupCctor = (f) => {
int insertPosition = 0;
foreach (var field in fieldsToEmit) {
var expr = TranslateField(field);
if (expr != null) {
var stmt = new JSExpressionStatement(expr);
f.Body.Statements.Insert(insertPosition++, stmt);
}
}
};
// Default values for instance fields of struct types are handled
// by the instance constructor.
// Default values for static fields of struct types are handled
// by the cctor.
// Everything else is emitted inline.
foreach (var f in typedef.Fields) {
if (f.IsStatic && NeedsStaticConstructor(f.FieldType))
continue;
if (EmulateStructAssignment.IsStruct(f.FieldType))
continue;
var expr = TranslateField(f);
if (expr != null)
AstEmitter.Visit(new JSExpressionStatement(expr));
}
if ((cctor != null) && !stubbed) {
TranslateMethod(context, output, cctor, cctor, false, null, null, fixupCctor);
} else if (fieldsToEmit.Length > 0) {
var fakeCctor = new MethodDefinition(".cctor", Mono.Cecil.MethodAttributes.Static, typeSystem.Void);
fakeCctor.DeclaringType = typedef;
var typeInfo = TypeInfoProvider.GetTypeInformation(typedef);
typeInfo.StaticConstructor = fakeCctor;
var identifier = MemberIdentifier.New(fakeCctor);
typeInfo.Members[identifier] = new Internal.MethodInfo(
typeInfo, identifier, fakeCctor, new ProxyInfo[0], false
);
// Generate the fake constructor, since it wasn't created during the analysis pass
TranslateMethodExpression(context, fakeCctor, fakeCctor);
TranslateMethod(context, output, fakeCctor, fakeCctor, false, null, null, fixupCctor);
}
}
