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Re: Drop frequencies from basic blocks
On 2017.11.05 at 11:55 +0100, Jan Hubicka wrote:
> > On 2017.11.03 at 16:48 +0100, Jan Hubicka wrote:
> > > this is updated patch which I have comitted after profiledbootstrapping x86-64
> >
> > Unfortunately, compiling tramp3d-v4.cpp is 6-7% slower after this patch.
> > This happens with an LTO/PGO bootstrapped gcc using --enable-checking=release.
>
> our periodic testers has also picked up the change and there is no compile time
> regression reported for tramp3d.
> https://gcc.opensuse.org/gcc-old/c++bench-czerny/tramp3d/
> so I would conclude that it is regression in LTO+PGO bootstrap. I am fixing one checking
> bug that may cause it (where we mix local and global profiles) so perhaps it will go away
> afterwards.
Just to confirm: pure PGO bootstrap is fine, e.g. on Ryzen:
(LTO/PGO) 17.65 sec ( +- 0.68% )
(PGO) 15.74 sec ( +- 0.27% )
--
Markus