Automatic PGO - Initial implementation (1/N)

[Eric Christopher]

On Tue, Sep 24, 2013 at 1:38 PM, Renato Golin <renato.golin at linaro.org> wrote:
> On 24 September 2013 19:38, Eric Christopher <echristo at gmail.com> wrote:
>>
>> -gline-tables-only (or -gmlt in gcc parlance). This will give you
>> accurate call stack information for each sample. Or at least as
>> accurate as I can get it.
>
>
> FWIW, I'm using perf with "-O3 -g" and LLVM has retained the line
> information quite well throughout all the inlining and optimizations that
> happened.
>

Excellent. That's what I would expect.

> I assume it's easier to keep line information than variable location ranges
> and types. The biggest problem is to separate the two emissions, I guess,
> not the quality of the resulting information.
>

Yep. That's precisely it.

-eric