[LLVMdev] DSA getNodeForValue() Returning NULL Sometimes

[Patrick Alexander Simmons]

Andrew Lenharth wrote:
> On Fri, Aug 7, 2009 at 4:45 PM, Patrick Alexander
> Simmons<simmon12 at cs.uiuc.edu> wrote:
>   
>> I'm iterating over all LoadInst and StoreInst-type Instructions in a
>> Function, and getNodeForValue() is sometimes returning NULL.  Why is
>> this happening?  Shouldn't every load from or store to memory correspond
>> to some DSNode?
>>     
>
>
> Not if the pointer is null or the pointer contains no information in
> the pass you are querying.
>
> Andrew
>
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>   

The program I'm analyzing is not dereferencing NULL pointers.  I'm 
querying the EquivBUDataStructures pass; what instances would cause the 
DSGraph not to have any information about the pointer (and I thought 
Unknown DSNodes were created for when we couldn't figure out the pointer 
value?).

Thanks,
--Patrick