[LLVMdev] Problems with instruction scheduling

[Hal Finkel]

----- Original Message -----
> From: "Paweł Bylica" <chfast at gmail.com>
> To: "Hal Finkel" <hfinkel at anl.gov>
> Cc: "LLVMdev" <llvmdev at cs.uiuc.edu>, "Jonas Paulsson" <jonas.paulsson at ericsson.com>
> Sent: Friday, May 22, 2015 9:19:14 AM
> Subject: Re: [LLVMdev] Problems with instruction scheduling
> 
> 
> 
> On Fri, May 22, 2015 at 4:09 PM Hal Finkel < hfinkel at anl.gov > wrote:
> 
> 
> ----- Original Message -----
> > From: "Paweł Bylica" < chfast at gmail.com >
> > To: "LLVMdev" < llvmdev at cs.uiuc.edu >
> > Sent: Friday, May 22, 2015 8:45:11 AM
> > Subject: Re: [LLVMdev] Problems with instruction scheduling
> > 
> > 
> > 
> > Any comments?
> 
> Not in particular, but I think we're pretty close to applying a
> rewrite by Jonas Paulsson (cc'd). If you can't find the discussions
> on the mailing list, please let us know.
> 
> -Hal
> 
> 
> 
> Thanks for the response.
> 
> 
> Do you mean "ScheduleDAGInstrs::buildSchedGraph() rewritten"
> http://reviews.llvm.org/D8705 ? If yes it is not the same fragment
> of code.

Ah, I see. That bug deals with ScheduleDAGRRList.

Andy, I thought that with the transition to source-order SDAG scheduling (and using MI scheduling instead), we were going to essentially get rid of that code. Is that right?

 -Hal

> 
> 
> - Paweł
> 
> 
> > 
> > 
> > On Thu, May 21, 2015 at 4:05 PM Paweł Bylica < chfast at gmail.com >
> > wrote:
> > 
> > 
> > 
> > Hi,
> > 
> > 
> > I'm trying to fix PR23405 - assert failure during instruction
> > scheduling in llc. I have related but more generic questions.
> > 
> > 
> > Is there any higher level description of the algorithm used for
> > instruction scheduling in this case? It is new area for me and I
> > would love to see bigger picture.
> > 
> > 
> > My currently smallest test case contains 90 DAG nodes. I got it by
> > manually reducing IR previously reduced by bugpoint. Is there a way
> > to reduce it more, maybe on DAG level? Identifying the part of the
> > DAG that causes the problem could be helpful.
> > 
> > 
> > 
> > - Paweł
> > _______________________________________________
> > LLVM Developers mailing list
> > LLVMdev at cs.uiuc.edu http://llvm.cs.uiuc.edu
> > http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
> > 
> 
> --
> Hal Finkel
> Assistant Computational Scientist
> Leadership Computing Facility
> Argonne National Laboratory
> 

-- 
Hal Finkel
Assistant Computational Scientist
Leadership Computing Facility
Argonne National Laboratory