llvm dev - Oct 2006 - [LLVMdev] alias analysis

Since Data Structure alias analysis inherits from ModulePass rather than 
FunctionPass, does that mean that it performs interprocedural alias 
analysis?  Further, if I compare pointers from two different functions, 
will I sometimes get a NoAlias response.

Regards,
Ryan

-- 
Ryan M. Lefever  [http://www.ews.uiuc.edu/~lefever]

Ryan's second question should be more generally phrased for the  
entire AliasAnalysis interface, not just DSA:  will it work to ask  
alias queries or mod/ref queries for a pair of pointers or a pair of  
instructions in two different functions?

--Vikram
http://www.cs.uiuc.edu/~vadve
http://llvm.cs.uiuc.edu/


On Oct 16, 2006, at 1:45 PM, Chris Lattner wrote:
> On Mon, 16 Oct 2006, Ryan M. Lefever wrote:
>> Since Data Structure alias analysis inherits from ModulePass  
>> rather than
>> FunctionPass, does that mean that it performs interprocedural alias
>> analysis?
>
> yes.
>
>> Further, if I compare pointers from two different functions,
>> will I sometimes get a NoAlias response.
>
> Don't do that :).  That's probably a bug in DSA, but fixing it  
> would be
> impractical.
>
> -Chris
>
> -- 
> http://nondot.org/sabre/
> http://llvm.org/
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> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
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On Mon, 16 Oct 2006, Ryan M. Lefever wrote:
> Since Data Structure alias analysis inherits from ModulePass rather than
> FunctionPass, does that mean that it performs interprocedural alias
> analysis?
yes.
> Further, if I compare pointers from two different functions,
> will I sometimes get a NoAlias response.
Don't do that :).  That's probably a bug in DSA, but fixing it would be 
impractical.

-Chris

-- 
http://nondot.org/sabre/
http://llvm.org/