Re: sparse-llvm issue with handling of phisrc instruction

[Luc Van Oostenryck <luc.vanoostenryck@gmail.com>]

On Wed, Mar 22, 2017 at 8:46 PM, Dibyendu Majumdar
<mobile@majumdar.org.uk> wrote:
> Hi Luc,
>
> On 22 March 2017 at 19:29, Luc Van Oostenryck
> <luc.vanoostenryck@gmail.com> wrote:
>>> >>>> I am trying to see if sparse-llvm can handle unsimplified IR output
>>> >>>> from linearizer. I think there is a problem in how it handles phisrc.
>>> >>>
>>> >>> Does your non-simplified sparse IR contain the liveness information?
>>> >>> I think those are needed for the handling of OP_PHI & OP_PHISOURCE
>>> >>> in sparse-llvm.
>>> >>>
>>> >>
>>> >> Probably not - I commented out everything in linearize_fn() from
>>> >> simplify_symbol_usage() and downwards. Please tell me if this is
>>> >> incorrect.
>>> >
>>> > As far as I understand, sparse-llvm needs track_pseudo_liveness().
>>> >
>>>
>>> Tried that - it made no difference.
>>
>> I'm not sure liveness info has much sense without simplification,
>> at least part of it.
>>
>
> You were right - I needed to retain following line:
>
> track_pseudo_death(C, ep);
>
> I mistakenly thought (going by name) that I had to call:
>
> track_pseudo_liveness(C, ep);

It's what I thought too :)

> Anyway it appears that this now populates the phi_users list so that
> the code works correctly.
>
> Thanks for your help.

Great.
You're welcome.