Hello, I'm a little confused about how method calls are transformed by the jitter into native code. I can see clearly now that two different cases are distinguished: non-virtual calls and virtual calls. When dealing with the former, only a method entry point is needed, which is obtained directly from the slot of the class method table in most cases. This entry point is stored in the CALLREG register and the call is done. However, the latter is giving some trouble to me, because now three values are taken into account:
- The method slot, which is obtained directly from an attribute of the MethodDesc class. - A Method Table offset. I assumed that this value was the location of a pointer to the class method table (table that is common to all the class objects), but now I'm not so sure about it. - A third value that the Jitter function buildCall stores in ARG_1 or ARG_2. I wasn't able to find what did it represent (this pointer?). The two first values are added in jitinterface code and the result is later added to the CALLREG register that stores the third, doing the call with that final result. The problem is that, as you can see, I wasn't able to know the meaning of some values so I couldn't fully understand how Rotor accesses virtual methods. I'm also trying to find how can this address be calculated accessing only to the metadata structures (like introspection MethodInfo.Invoke calls should do). I tried to do the following: method->GetAddrofcode(ObjectToOBJECTREF(thisObj)); But I'm not obtaining the same value that is used by the jitter in the virtual calls. ¿Am I forgetting or misunderstanding something? ¿Can anybody give me some help? Thank you very much in advance, Jose M. =================================== This list is hosted by DevelopMentor® http://www.develop.com View archives and manage your subscription(s) at http://discuss.develop.com
