public override void ExitUnaryExpr(GoParser.UnaryExprContext context)
{
// unaryExpr
// : primaryExpr
// | ('+' | '-' | '!' | '^' | '*' | '&' | '<-') expression
if (PrimaryExpressions.TryGetValue(context.primaryExpr(), out string primaryExpression))
{
UnaryExpressions[context] = primaryExpression;
}
else if (context.expression() != null)
{
string unaryOP = context.children[0].GetText();
if (unaryOP.Equals("^", StringComparison.Ordinal))
{
unaryOP = "~";
}
else if (unaryOP.Equals("<-", StringComparison.Ordinal))
{
// TODO: Handle channel value access (update when channel class is created):
unaryOP = null;
UnaryExpressions[context] = $"{Expressions[context.expression()]}.Receive()";
}
else if (unaryOP.Equals("&", StringComparison.Ordinal))
{
// TODO: Handle pointer acquisition context - may need to augment pre-scan metadata for heap allocation notation
unaryOP = null;
UnaryExpressions[context] = $"ref {Expressions[context.expression()]}";
}
else if (unaryOP.Equals("*", StringComparison.Ordinal))
{
// TODO: Handle pointer dereference context - if this is a ref variable, Deref call is unnecessary
unaryOP = null;
UnaryExpressions[context] = $"{Expressions[context.expression()]}.Deref";
}
if ((object)unaryOP != null)
{
UnaryExpressions[context] = $"{unaryOP}{Expressions[context.expression()]}";
}
}
else if (!UnaryExpressions.ContainsKey(context))
{
AddWarning(context, $"Unexpected unary expression \"{context.GetText()}\"");
}
}
public override void ExitUnaryExpr(GoParser.UnaryExprContext context)
{
base.ExitUnaryExpr(context);
if (!InFunction || !(context.primaryExpr() is null) && PrimaryExpressions.ContainsKey(context.primaryExpr()) ||
context.expression() is null || !Expressions.TryGetValue(context.expression(), out ExpressionInfo expression))
{
return;
}
ParameterInfo[] parameters = CurrentFunction.Signature.Signature.Parameters;
string unaryOP = context.children[0].GetText();
if (!unaryOP.Equals("*", StringComparison.Ordinal))
{
return;
}
ParameterInfo pointerParam = parameters.FirstOrDefault(parameter => parameter.Name.Equals(expression.Text));
if (!(pointerParam is null) && pointerParam.Type is PointerTypeInfo pointer)
{
TypeInfo targetType = pointer.TargetTypeInfo.Clone();
targetType.IsByRefPointer = true;
string derefPointerExpression = expression.Text;
// Handle pointer-to-pointer dereferencing
int derefs = pointer.Name.Count(chr => chr == '*');
if (derefs > 1)
{
for (int i = 1; i < derefs; i++)
{
derefPointerExpression += ".val";
}
}
// Implicitly dereference pointer parameter when dereference operator (*) is used
UnaryExpressions[context] = new ExpressionInfo
{
Text = derefPointerExpression,
Type = targetType
};
}
}
public override void ExitUnaryExpr(GoParser.UnaryExprContext context)
{
base.ExitUnaryExpr(context);
ExpressionInfo expression = null;
if (!(context.primaryExpr() is null) && !PrimaryExpressions.ContainsKey(context.primaryExpr()) ||
!(context.expression() is null) && !Expressions.TryGetValue(context.expression(), out expression) ||
expression is null)
{
return;
}
// Taking the address of a variable means making a stack variable heap allocated
if (context.children[0].GetText().Equals("&", StringComparison.Ordinal) && m_variables.TryGetValue(expression.Text, out VariableInfo variable))
{
variable.HeapAllocated = true;
}
}
