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Re: [PATCH] alternative hirate for builtin_expert

From: Rong Xu <xur at google dot com>
To: Jan Hubicka <hubicka at ucw dot cz>
Cc: GCC Patches <gcc-patches at gcc dot gnu dot org>, David Li <davidxl at google dot com>
Date: Wed, 2 Oct 2013 15:49:25 -0700
Subject: Re: [PATCH] alternative hirate for builtin_expert
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References: <CAF1bQ=TH5+Qfd1MsAUDBJj+F-zizymTTGh7HxyuXUbaPqd-mng at mail dot gmail dot com> <CAF1bQ=Q_eiCz8AYkU-c=Xu7quQ0vy8eP=pi9QZt+QOF4vicnsg at mail dot gmail dot com> <20131002160827 dot GB7181 at kam dot mff dot cuni dot cz> <CAF1bQ=Snvzzmm=AEr-crrKhopRugKbcExH+wFCyCcgZZHz+Uow at mail dot gmail dot com> <20131002213102 dot GE7181 at kam dot mff dot cuni dot cz>

Here is the new patch. Honaz: Could you take a look?

Thanks,

-Rong

On Wed, Oct 2, 2013 at 2:31 PM, Jan Hubicka <hubicka@ucw.cz> wrote:
>> Thanks for the suggestion. This is much cleaner than to use binary parameter.
>>
>> Just want to make sure I understand it correctly about the orginal hitrate:
>> you want to retire the hitrate in PRED_BUILTIN_EXPECT and always use
>> the one specified in the biniltin-expect-probability parameter.
>
> Yes.
>>
>> Should I use 90% as the default? It's hard to fit current value 0.9996
>> in percent form.
>
> Yes, 90% seems fine.  The original value was set quite arbitrarily and no real
> performance study was made as far as I know except yours. I think users that
> are sure they use expect to gueard completely cold edges may just use 100%
> instead of 0.9996, so I would not worry much about the precision.
>
> Honza
>>
>> -Rong
>> >
>> > OK with that change.
>> >
>> > Honza

Attachment: p2_patch_v2
Description: Binary data

Follow-Ups:
- Re: [PATCH] alternative hirate for builtin_expert
  - From: Jan Hubicka
- Re: [PATCH] alternative hirate for builtin_expert
  - From: Ramana Radhakrishnan

References:
- Re: [PATCH] alternative hirate for builtin_expert
  - From: Rong Xu
- Re: [PATCH] alternative hirate for builtin_expert
  - From: Jan Hubicka
- Re: [PATCH] alternative hirate for builtin_expert
  - From: Rong Xu
- Re: [PATCH] alternative hirate for builtin_expert
  - From: Jan Hubicka

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