Re: [GOOGLE] Report the difference between profiled and guessed or annotated branch probabilities.

[Yi Yang <ahyangyi at google dot com>]

Fixed. (outputting only the integer percentage)

On Mon, Jun 30, 2014 at 2:20 PM, Yi Yang <ahyangyi@google.com> wrote:
> This is intermediate result, which is meant to be consumed by further
> post-processing. For this reason I'd prefer to put a number without
> that percentage sign.
>
> I'd just output (int)(probability*100000000+0.5). Does this look good
> for you? Or maybe change that to 1000000 since six digits are more
> than enough. I don't see a reason to intentionally drop precision
> though.
>
> Note that for the actual probability, the best way to store it is to
> store the edge count, since the probability is just
> edge_count/bb_count. But this causes disparity in the formats of the
> two probabilities.
>
> On Mon, Jun 30, 2014 at 2:12 PM, Dehao Chen <dehao@google.com> wrote:
>> Let's use %d to replace %f (manual conversion, let's do xx%).
>>
>> Dehao
>>
>> On Mon, Jun 30, 2014 at 2:06 PM, Yi Yang <ahyangyi@google.com> wrote:
>>> Fixed.
>>>
>>> Also, I spotted some warnings caused by me using "%lf"s in snprintf().
>>> I changed these to "%f" and tested.
>>>
>>>
>>> On Mon, Jun 30, 2014 at 1:49 PM, Dehao Chen <dehao@google.com> wrote:
>>>> You don't need extra space to store file name in locus_information_t.
>>>> Use pointer instead.
>>>>
>>>> Dehao
>>>>
>>>>
>>>> On Mon, Jun 30, 2014 at 1:36 PM, Yi Yang <ahyangyi@google.com> wrote:
>>>>>
>>>>> I refactored the code and added comments. A bug (prematurely breaking
>>>>> from a loop) was fixed during the refactoring.
>>>>>
>>>>> (My last mail was wrongly set to HTML instead of plain text. I
>>>>> apologize for that.)
>>>>>
>>>>> 2014-06-30  Yi Yang  <ahyangyi@google.com>
>>>>>
>>>>>     * auto-profile.c (get_locus_information)
>>>>>     (fill_invalid_locus_information, record_branch_prediction_results)
>>>>>     (afdo_calculate_branch_prob, afdo_annotate_cfg): Main comparison and
>>>>>     reporting logic.
>>>>>     * cfg-flags.def (PREDICTED_BY_EXPECT): Add an extra flag representing
>>>>>     an edge's probability is predicted by annotations.
>>>>>     * predict.c (combine_predictions_for_bb): Set up the extra flag on an
>>>>>     edge when appropriate.
>>>>>     * common.opt (fcheck-branch-annotation)
>>>>>     (fcheck-branch-annotation-threshold=): Add an extra GCC option to turn
>>>>>     on report
>>>>>
>>>>> On Fri, Jun 27, 2014 at 3:20 PM, Xinliang David Li <davidxl@google.com> wrote:
>>>>> > Hi Yi,
>>>>> >
>>>>> > 1) please add comments before new functions as documentation -- follow
>>>>> > the coding style guideline
>>>>> > 2) missing documenation on the new flags (pointed out by Gerald)
>>>>> > 3) Please refactor the check code in afdo_calculate_branch_prob into a
>>>>> > helper function
>>>>> >
>>>>> > 4) the change log is not needed for google branches, but if provided,
>>>>> > the format should follow the style guide (e.g, function name in () ).
>>>>> >
>>>>> > David
>>>>> >
>>>>> >
>>>>> > On Fri, Jun 27, 2014 at 11:07 AM, Yi Yang <ahyangyi@google.com> wrote:
>>>>> >> Hi,
>>>>> >>
>>>>> >> This patch adds an option. When the option is enabled, GCC will add a
>>>>> >> record about it in an elf section called
>>>>> >> ".gnu.switches.text.branch.annotation" for every branch.
>>>>> >>
>>>>> >> gcc/
>>>>> >>
>>>>> >> 2014-06-27 Yi Yang <ahyangyi@google.com>
>>>>> >>
>>>>> >>         * auto-profile.c: Main comparison and reporting logic.
>>>>> >>         * cfg-flags.def: Add an extra flag representing an edge's
>>>>> >> probability is predicted by annotations.
>>>>> >>         * predict.c: Set up the extra flag on an edge when appropriate.
>>>>> >>         * common.opt: Add an extra GCC option to turn on this report mechanism

Attachment: 0001-Report-the-difference-between-profiled-and-guessed-o.patch.txt
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