https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79534
James Greenhalgh <jgreenhalgh at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2017-03-29
Ever confirmed|0 |1
--- Comment #5 from James Greenhalgh <jgreenhalgh at gcc dot gnu.org> ---
It is always helpful to provide the full command line and configuration used,
along with rough details of the platform you are using.
Compiling with:
gcc -O3 -mcpu=cortex-a57
I can see the performance difference reported here when running on Cortex-A57,
Cortex-A72 and Cortex-A53 based systems, while with:
gcc -O3
(i.e. using the generic tuning structures) I see no meaningful performance
differences across multiple microarchitectures.
So, confirmed. Though this is more likely to be a deficiency in the heuristics
in the back-end ifcvt cost model than a regression directly introduced by
Honza's patch.
