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Re: [PATCH, 4.9/4.10] Profile based option tuning

On Wed, Jul 23, 2014 at 1:04 PM, Pengfei Yuan <> wrote:
> I guess some optimizations are controlled only by "optimize_size", not
> by the profile.

I only see tree-inline.c:estimate_move_cost which we should indeed fix,
it could make a significant difference.

One other use in tree-ssa-phiopt.c, but probably doesn't really matter.


> Other optimizations are controlled by the profile.
> So this patch does not have very much effectiveness (only 0.9% size reduction).
> 2014-07-23 17:26 GMT+08:00 Richard Biener <>:
>> On Wed, Jul 23, 2014 at 2:39 AM, Pengfei Yuan <> wrote:
>>> In the experiment, about 60% (1019/1699) profile data files are empty
>>> (all counters are zero).
>> Well, but you are globally overriding options even for the parts with
>> profile.  The whole point of profile-feedback is to get at the interesting
>> parts (those with non-zero counters).
>> What you say is that not enough parts of the compiler care for
>> the actual profiles and thus portions with all-zero counters are
>> treated as if they were hot?  Then better fix that.
>> Richard.
>>> 2014-07-22 21:39 GMT+08:00 Richard Biener <>:
>>>> On Mon, Jul 21, 2014 at 7:13 AM, Pengfei Yuan <> wrote:
>>>>> Hi,
>>>>> This patch tunes optimization options based on profile data:
>>>>> * Disable PGO options if profile is not available or empty.
>>>>> * Optimize for size if profile is available but empty.
>>>> Err ... these don't seem interesting cases to "optimize" for?
>>>> Richard.

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