private void EmitFlagValue(IILEmitter emitter, IRng rng)
{
if (Constraints != null)
{
Constraints.EmitValue(emitter, rng);
}
else
{
var(signed, bytes) = IntConstraints.GetProps(Flag.Field.FieldType.ElementType);
emitter.Const(Value.Value, bytes, signed);
}
}
public void EmitChecker(IILEmitter emitter, IRng rng, Instruction normalFlowTarget)
{
var fv = Flag.Field;
emitter.Emit(OpCodes.Ldarg_0);
emitter.Emit(OpCodes.Ldfld, emitter.Importer.Import(fv));
if (Constraints != null)
{
emitter.NumericConversion(fv.FieldType.ElementType, Constraints.ElementType, false);
Constraints.EmitChecker(rng, emitter, normalFlowTarget);
}
else
{
var(signed, bytes) = IntConstraints.GetProps(Flag.Field.FieldType.ElementType);
emitter.Const(Value.Value, bytes, signed);
emitter.Emit(OpCodes.Bne_Un, normalFlowTarget);
}
}
protected InjectedFeature(InjectableMethod method, Var output, IRng rng)
{
Method = method;
Output = output;
var maxFlags = 15;
bool overlaps;
do
{
var flag = method.Type.GetOrAddFlag(rng);
var(signed, bytes) = IntConstraints.GetProps(flag.Field.FieldType.ElementType);
var maxOverlaps = 10;
do
{
long? value;
IntConstraints constraints;
if (rng.NextBoolean())
{
value = null;
constraints = IntConstraints.Generate(rng, bytes, signed);
}
else
{
value = IntConstraints.NextInt(rng, bytes, signed);
constraints = null;
}
overlaps = false;
foreach (var feature in flag.Features)
{
if (feature.Value.HasValue)
{
if (value.HasValue && feature.Value.Value == value.Value)
{
overlaps = true;
}
else if (constraints != null && constraints.Contains(feature.Value.Value))
{
overlaps = true;
}
}
else
{
if (value.HasValue && feature.Constraints.Contains(value.Value))
{
overlaps = true;
}
else if (constraints != null && constraints.Overlaps(feature.Constraints))
{
overlaps = true;
}
}
if (overlaps)
{
break;
}
}
if (!overlaps)
{
Value = value;
Constraints = constraints;
flag.AddFeature(this);
Flag = flag;
break;
}
} while (maxOverlaps-- > 0);
} while (overlaps && maxFlags-- > 0);
if (overlaps)
{
throw new Exception("could not create flag for injected feature");
}
}