public RuleResult CheckMethod(MethodDefinition method)
{
if (!method.HasBody)
{
return(RuleResult.DoesNotApply);
}
// exclude methods that don't have calls
if (!OpCodeBitmask.Calls.Intersect(OpCodeEngine.GetBitmask(method)))
{
return(RuleResult.DoesNotApply);
}
foreach (Instruction ins in method.Body.Instructions)
{
MethodReference mr = ins.GetMethod();
if ((mr == null) || !mr.DeclaringType.IsNamed("System", "Math"))
{
continue;
}
Instruction value = null;
string name = mr.Name;
switch (name)
{
case "Ceiling":
case "Floor":
case "Truncate":
value = ins.Previous;
break;
case "Round":
// variable number of arguments for different overloads
int n = ins.GetPopCount(method);
value = ins.Previous;
while (value != null)
{
// stop before first parameter
if (n == 1)
{
break;
}
n += value.GetPopCount(method) - value.GetPushCount();
value = value.Previous;
}
break;
}
if (value == null)
{
continue;
}
TypeReference type = GetArgumentType(value, method);
if (type == null)
{
continue;
}
string msg = String.Format(CultureInfo.InvariantCulture, "Math.{0} called on a {1}.",
name, type.GetFullName());
Runner.Report(method, ins, Severity.Medium, Confidence.Normal, msg);
}
return(Runner.CurrentRuleResult);
}
