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Re: [PATCH] Redesign jump threading profile updates


Ping. Jeff, any update on when you can look at this?
Thanks,
Teresa

On Tue, May 27, 2014 at 7:10 AM, Teresa Johnson <tejohnson@google.com> wrote:
> On Thu, Apr 17, 2014 at 6:23 AM, Teresa Johnson <tejohnson@google.com> wrote:
>> On Wed, Apr 16, 2014 at 10:39 PM, Jeff Law <law@redhat.com> wrote:
>>> On 03/26/14 17:44, Teresa Johnson wrote:
>>>>
>>>> Recently I discovered that the profile updates being performed by jump
>>>> threading were incorrect in many cases, particularly in the case where
>>>> the threading path contains a joiner. Some of the duplicated
>>>> blocks/edges were not getting any counts, leading to incorrect
>>>> function splitting and other downstream optimizations, and there were
>>>> other insanities as well. After making a few attempts to fix the
>>>> handling I ended up completely redesigning the profile update code,
>>>> removing a few places throughout the code where it was attempting to
>>>> do some updates.
>>>
>>> The profile updates in that code is a mess.  It's never really been looked
>>> at in any systematic way, what's there is ad-hoc and usually in response to
>>> someone mentioning the profile data was incorrectly updated.   As we rely
>>> more and more on that data the ad-hoc updating is going to cause us more and
>>> more pain.
>>>
>>> So any work in this space is going to be greatly appreciated.
>>>
>>> I'll have to look at this in some detail.  But I wanted you to know I was
>>> aware of the work and it's in my queue.
>>
>> Great, thanks for the update! I realize that it is not a trivial
>> change so it would take some time to get through. Hopefully it should
>> address the ongoing profile fixup issues.
>> Teresa
>
> Ping.
> Thanks,
> Teresa
>
>>
>>>
>>> Thanks!
>>>
>>> jeff
>>
>>
>>
>> --
>> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413
>
>
>
> --
> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413



-- 
Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413


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