On Tue, Oct 5, 2010 at 11:20 AM, Mariano Martinez Peck < marianopeck@gmail.com> wrote:
On Tue, Oct 5, 2010 at 7:50 PM, Eliot Miranda eliot.miranda@gmail.comwrote:
On Tue, Oct 5, 2010 at 9:23 AM, Mariano Martinez Peck < marianopeck@gmail.com> wrote:
Hi. So....if I want to intercept ALL message sends....going to #normalSend is not enough since I have #class, #==, Float>>#+ etc that are executed directly like bytecodes. So...my questions are now:
- Those special selectors are those that are in "Smalltalk
specialSelectors" ? are there more? all from there are special?
- All those "Smalltalk specialSelectors" have their associated bytecode
primitive in Interpreter?? If true, then I should modify all bytecodePrim* in Interpreter. I am right? If I do that, that's all ? I am intercepting everything?
Right. Just modify all of them to eliminate the optimized code and to revert to normalSend.
Thanks Eliot. I didn't understand. What is the optimized code? I checked all bytecodePrim* and the ones that DO NOT send "self normalSend" at the end, are very few. The problem is that some return before returning "self normalSend". So...I should modify all those who DO NOT call "self normalSend" at the end and those which return before.
Change them all so they do a normalSend and nothing else, e.g.
bytecodePrimAdd messageSelector := self specialSelector: 0. argumentCount := 1. self normalSend
Or change the part of the bytecode table that specifies the special selector primitives to read (176 207 sendSpecialSelectorBytecode)
sendSpecialSelectorBytecode | selectorIndex specialSelectors | selectorIndex := (currentBytecode - 176) * 2. specialSelectors := self splObj: SpecialSelectors. messageSelector := self fetchPointer: selectorIndex ofObject: specialSelectors. argumentCount := self fetchInteger: selectorIndex + 1 ofObject: specialSelectors. self normalSend
But most of all try and slow down and understand what is going on; then you will be able to answer your own questions. Reading the blue bookhttp://www.mirandabanda.org/bluebook/bluebook_imp_toc.htmlwill help.
Providing you also look at the perform and method evaluation primitives I think you'll get all sends.
#primitivePerform* and #primitiveExecuteMethod* ???
There is another way. Modify the Smalltalk compiler to to use the special selector sends.
Thanks Eliot for the idea. Can you explain me a little more (sorry, newbie here!). You mean that with the Compiler I can do that all method sends use the normal send instead of special bytecodes or primitives?
Yes. If you modify the compiler not to use the StdSelectors then the compiler will emit normal sends for all the special selectors. Again I think if you slowed down and started playing ore you would discover this for yourself and in the end be more productive. I know its hard and frustrating initially. But my own competence comes directly from having played around in this way.
best, Eliot
Thank you very much.
Mariano
Thanks a lot in advance,
Mariano
On Sun, Oct 3, 2010 at 11:09 PM, Craig Latta craig@netjam.org wrote:
Craig Latta has done all this work, talk to him.
Sure, I'd be happy to discuss it.-C
-- Craig Latta www.netjam.org
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