private void EnqueueStartNode()
{
var initialProgramState = new ProgramState();
foreach (var parameter in declarationParameters)
{
var sv = SymbolicValue.Create(parameter.Type);
initialProgramState = initialProgramState.StoreSymbolicValue(parameter, sv);
initialProgramState = SetNonNullConstraintIfValueType(parameter, sv, initialProgramState);
}
EnqueueNewNode(new ProgramPoint(cfg.EntryBlock), initialProgramState);
}
private ProgramState VisitVariableDesignation(VariableDesignationSyntaxWrapper variableDesignation, ProgramState programState, bool singleVariable)
{
var newProgramState = programState;
if (DiscardDesignationSyntaxWrapper.IsInstance(variableDesignation))
{
// Push value for the discard, it will be popped when visiting the block for the
// corresponding case statement.
newProgramState = newProgramState.PushValue(SymbolicValue.Create());
}
else if (SingleVariableDesignationSyntaxWrapper.IsInstance(variableDesignation))
{
// "x is string s" is equivalent to "s = x"; both symbolic values should remain on stack
var singleVariableDesignation = (SingleVariableDesignationSyntaxWrapper)variableDesignation;
// associate variable with new SV
var variableSymbol = SemanticModel.GetDeclaredSymbol(singleVariableDesignation);
var newSymbolicValue = SymbolicValue.Create();
newProgramState = SetNewSymbolicValueIfTracked(variableSymbol, newSymbolicValue, newProgramState);
if (singleVariable)
{
// When the pattern is "x is Type t" we know that "t != null", hence (SV != null)
newProgramState = newProgramState.PushValue(new ValueNotEqualsSymbolicValue(newSymbolicValue, SymbolicValue.Null));
}
}
else if (ParenthesizedVariableDesignationSyntaxWrapper.IsInstance(variableDesignation))
{
var parenthesizedVariableDesignation = (ParenthesizedVariableDesignationSyntaxWrapper)variableDesignation;
foreach (var variable in parenthesizedVariableDesignation.Variables)
{
// the variables in the deconstruction should not receive "Not Null" constraint
newProgramState = VisitVariableDesignation(variable, newProgramState, singleVariable: false);
}
}
else
{
throw new NotSupportedException($"{variableDesignation.SyntaxNode.Kind()}");
}
return(newProgramState);
}
private ProgramState VisitIdentifier(IdentifierNameSyntax identifier, ProgramState programState)
{
var newProgramState = programState;
var symbol = SemanticModel.GetSymbolInfo(identifier).Symbol;
var typeSymbol = SemanticModel.GetTypeInfo(identifier).Type;
var sv = newProgramState.GetSymbolValue(symbol);
if (sv == null)
{
var fieldSymbol = symbol as IFieldSymbol;
if (fieldSymbol != null) // TODO: Fix me when implementing SLVS-1130
{
sv = fieldSymbol.CreateFieldSymbolicValue();
newProgramState = newProgramState.StoreSymbolicValue(symbol, sv);
}
else
{
sv = SymbolicValue.Create(typeSymbol);
}
}
newProgramState = newProgramState.PushValue(sv);
var parenthesized = identifier.GetSelfOrTopParenthesizedExpression();
var argument = parenthesized.Parent as ArgumentSyntax;
if (argument == null ||
argument.RefOrOutKeyword.IsKind(SyntaxKind.None))
{
return(SetNonNullConstraintIfValueType(symbol, sv, newProgramState));
}
newProgramState = newProgramState.PopValue();
sv = SymbolicValue.Create(typeSymbol);
newProgramState = newProgramState.PushValue(sv);
newProgramState = SetNonNullConstraintIfValueType(symbol, sv, newProgramState);
return(SetNewSymbolicValueIfTracked(symbol, sv, newProgramState));
}