[LLVMdev] Alias analysis and instruction level parallelism

[Pertti Kellomäki]

Florian Brandner wrote:
> an other option would be to save the GEP instructions and provide a mapping 
> between them and the lowered arithmetic. it's not very clean but it would be 
> safe, and probably work well.

In my opinion this seems like the obvious way to go. The information
is already there, so reverse engineering it back does not sound too
clever. Of course if the reverse engineering would provide useful
information about pointers that do not originate from GEP instructions,
then it might be worthwhile. But my feeling is that at least for our
purposes, GEPs really are the interesting stuff. My understanding is
that parallelizing C compilers try to convert pointer arithmetic back
to array access in order to make sense of them, so essentially turning
them into GEPs. Certainly the dependence literature is heavily array
based.
-- 
Pertti