Richard Frith-Macdonald schrieb: > > Yes, though ideally it could work ... because > [NSDistantObject-methodForSelector:] could return the address of code > which will forward the message to the other process. This would > actually not be too hard to implement.
Sounds neat! > I'm not to clear on what an NSDistantObject ought to do according to the > documentation though: > The documentation doesn't say it implements -methodForSelector: or > +instanceMethodForSelector: so perhaps it should return the address of > the method in the remote process ... which is kind of odd. If you > accept that interpretation then the common practice of caching method > implementations for optimisation must always be considered unsafe unless > you can guarantee that no proxy object will ever reach that code. Yes... if you take the language by the letter you can implement an object that call arbitrary invocation in forwardInvocation:. Nothing in the the language says that sending the same message twice must invoke the identical implementation. If you take that as a given both -methodForSelector and +instanceMethodForSelector: (and subsequently IMP caching) are only useful for defined methods of defined classes (albeit most classes and methods). > So ... technically the optimisation in NSAutoreleasePool is clearly > unsafe, but in practice it's probably worth keeping it even so (the > person who suggested it to me said it had made a 20% performance boost > to their code). I fully agree that for practicality such optimization are more than useful in benchmarked cases and I'm willing to do what is necessary to have it 'just work'... But that can be hard or sometimes impossible. In this case I think we have decent compromise. And I'd like the get_imp approach even better. I'm not sure whether we need to take special precautions for double release checking wrt EOFault/NSAutoreleasePool and the cached IMP. _______________________________________________ Gnustep-dev mailing list Gnustep-dev@gnu.org http://lists.gnu.org/mailman/listinfo/gnustep-dev
