[LLVMdev] Post-RA Def/Use Information

[Joshua Cranmer]

On 6/15/2012 6:00 PM, Owen Anderson wrote:
> On Jun 15, 2012, at 2:54 PM, dag at cray.com wrote:
>
>> Looking through TOT sources, I don't see anything that would provide
>> def/use chains (or equivalent information) post register allocation.  I
>> would like to write some peeps to clean up various target-specific
>> things but for safety I will need such information.
>>
>> Is such an analysis pass available somewhere that I've missed?  If not,
>> is there a better way to find all uses of a defined value post register
>> allocation?  Writing a def/use chain pass would not be hard but if the
>> information is already there I'd rather avoid that cost.  :)
> Do the MachineRegisterInfo::def_begin/def_end/use_begin/use_end iterators not work on physical registers?
>

I seem to recall, the last time I used those, that they ended up being a 
fairly flat list of all definitions and all uses of a physical 
registers, not all the uses of a particular definition (or vice versa).

-- 
Joshua Cranmer
News submodule owner
DXR coauthor