[LLVMdev] AliasAnalysis tutorial

[Julien Schmitt]

Hi !
I'm writting an AliasAnalysis using the online tutorial 
(http://www.llvm.org/docs/AliasAnalysis.html).
My problem is to chain this pass (function Pass in my case) with the 
basicAA ...
I know that my pass is running (runOnFunction) but the virtual methods  
derived from AliasAnalysis
(alias,  getModRefInfo, etc ... ) are never called  (even in the case 
wherer the basicAA reaches the end of 'getModRefInfo(CallSite CS, Value 
*P, unsigned Size)' virtual function)

Either, i misunderstood the process of AA  (I expect that each virtual 
method of each AA are called if they are defined until
one of them gives a result (and that's why we need the last 'return') ( 
= the chain) ,  but maybe it's not true )
or i have forgotten a special instruction (something like 'registration 
of a new AA' ) , or maybe both :)
Could anybody give me an advice, please ?

Thank you !

Julien