[llvm-dev] Reversion of rL292621 caused about 7% performance regressions on Cortex-M

[Wei Mi via llvm-dev]

Sure. Will keep you posted.

Thanks,
Wei.

On Fri, Jan 27, 2017 at 10:31 AM, Evgeny Astigeevich
<Evgeny.Astigeevich at arm.com> wrote:
> Hi Wei,
>
> Thank you for information.
> Please let me know about any progress in fixing the failures.
> I can help with checking that the final patch gives the same level of performance improvements.
>
> Kind regards,
> Evgeny Astigeevich
> Senior Compiler Engineer
> Compilation Tools
> ARM
>
>
>> -----Original Message-----
>> From: Wei Mi [mailto:wmi at google.com]
>> Sent: Friday, January 27, 2017 6:20 PM
>> To: Evgeny Astigeevich
>> Cc: llvm-dev; nd
>> Subject: Re: Reversion of rL292621 caused about 7% performance
>> regressions on Cortex-M
>>
>> Hi Evgeny,
>>
>> The failure is a compiler crash on an out-of-tree target in apple.
>> Quentin is helping to find a reproducible but havn't succeeded yet.
>> Once I get a reproducible, I will fix it. Thanks for the interest on the work.
>> Details about the crash can be found here:
>> http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-
>> 20170123/422853.html
>>
>> Thanks,
>> Wei.
>>
>>
>> On Fri, Jan 27, 2017 at 10:11 AM, Evgeny Astigeevich
>> <Evgeny.Astigeevich at arm.com> wrote:
>> > Hi Wei,
>> >
>> >
>> >
>> > Your reversion of rL292621 caused about 7% performance regressions in
>> > our benchmark on Cortex-M7/M4.
>> >
>> > In your commit comment I see it causes build bot failures.
>> >
>> > What kind are the failures? Compiler crashes or incorrect code generation?
>> > Will you fix them?
>> >
>> > We are interested in the changes because of performance improvements
>> > they give.
>> >
>> >
>> >
>> > Kind regards,
>> >
>> > Evgeny Astigeevich
>> >
>> > Senior Compiler Engineer
>> > Compilation Tools
>> > ARM
>> >
>> >