[llvm-dev] NPM and code-size

[Xinliang David Li via llvm-dev]

Extracting some test cases to demonstrate the issue would be helpful for
triaging purposes.

David

On Wed, Jul 22, 2020 at 9:00 AM Arthur Eubanks <aeubanks at google.com> wrote:

> There's no official timeline for switching to the NPM, but I am trying to
> get it ready ASAP.
> What flags are you using for code size? I'm not familiar with the
> internals of the NPM optimization passes especially in regards to code
> size, adding some people who may be more familiar.
>
> On Wed, Jul 22, 2020 at 7:51 AM Sjoerd Meijer via llvm-dev <
> llvm-dev at lists.llvm.org> wrote:
>
>> (NPM: new pass manager;  LPM: legacy pass manager)
>>
>> In a first quick experiment today I compared code-size of the LMP vs. the
>> NMP for the CSiBE benchmark (and some other), and this shows code-size
>> increases with the NPM that would probably be unacceptable for us. So, now
>> I am wondering how/if we need to mitigate this, and have a bunch of
>> questions.
>>
>> As I've noticed quite some activity around the NPM recently, I am first
>> of all curious if there's an idea or estimate when the NPM will be enabled?
>> And sorry if I missed this. That would give us an idea how much time we
>> have to tune the NMP and the pipeline for code-size, which I think would be
>> the obvious mitigation. Other questions would be if the NPM is mostly tuned
>> for performance at the moment, if others have observed code-size increases
>> too, and if flipping the switch from the LPM to NPM would be for all
>> optimisation levels at the same time, or if we e.g. will fall back to the
>> old one for some?
>>
>> Thanks,
>> Sjoerd.
>> _______________________________________________
>> LLVM Developers mailing list
>> llvm-dev at lists.llvm.org
>> https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20200722/fd417a96/attachment.html>