static FieldDefinition GetFieldDefinition(FieldReference field)
{
return(CecilExtensions.ResolveWithinSameModule(field));
}
static MethodDefinition GetMethodDefinition(MethodReference method)
{
return(CecilExtensions.ResolveWithinSameModule(method));
}
public SymbolicValue Eval(ILExpression expr)
{
SymbolicValue left, right;
switch (expr.Code)
{
case ILCode.Sub:
left = Eval(expr.Arguments[0]);
right = Eval(expr.Arguments[1]);
if (left.Type != SymbolicValueType.State && left.Type != SymbolicValueType.IntegerConstant)
{
return(Failed());
}
if (right.Type != SymbolicValueType.IntegerConstant)
{
return(Failed());
}
return(new SymbolicValue(left.Type, unchecked (left.Constant - right.Constant)));
case ILCode.Ldfld:
if (Eval(expr.Arguments[0]).Type != SymbolicValueType.This)
{
return(Failed());
}
if (CecilExtensions.ResolveWithinSameModule(expr.Operand as FieldReference) != stateField)
{
return(Failed());
}
return(new SymbolicValue(SymbolicValueType.State));
case ILCode.Ldloc:
ILVariable loadedVariable = (ILVariable)expr.Operand;
if (stateVariables.Contains(loadedVariable))
{
return(new SymbolicValue(SymbolicValueType.State));
}
else if (loadedVariable.IsParameter && loadedVariable.OriginalParameter.Index < 0)
{
return(new SymbolicValue(SymbolicValueType.This));
}
else
{
return(Failed());
}
case ILCode.Ldc_I4:
return(new SymbolicValue(SymbolicValueType.IntegerConstant, (int)expr.Operand));
case ILCode.Ceq:
case ILCode.Cne:
left = Eval(expr.Arguments[0]);
right = Eval(expr.Arguments[1]);
if (left.Type != SymbolicValueType.State || right.Type != SymbolicValueType.IntegerConstant)
{
return(Failed());
}
// bool: (state + left.Constant == right.Constant)
// bool: (state == right.Constant - left.Constant)
return(new SymbolicValue(expr.Code == ILCode.Ceq ? SymbolicValueType.StateEquals : SymbolicValueType.StateInEquals, unchecked (right.Constant - left.Constant)));
case ILCode.LogicNot:
SymbolicValue val = Eval(expr.Arguments[0]);
if (val.Type == SymbolicValueType.StateEquals)
{
return(new SymbolicValue(SymbolicValueType.StateInEquals, val.Constant));
}
else if (val.Type == SymbolicValueType.StateInEquals)
{
return(new SymbolicValue(SymbolicValueType.StateEquals, val.Constant));
}
else
{
return(Failed());
}
default:
return(Failed());
}
}