On Thu, Nov 19, 2015 at 04:04:41PM -0600, Evandro Menezes wrote:
On 11/05/2015 02:51 PM, Evandro Menezes wrote:
2015-11-05 Evandro Menezes <e.menezes@samsung.com>
gcc/
* config/aarch64/aarch64.c (aarch64_override_options_internal):
Increase loop peeling limit.
This patch increases the limit for the number of peeled insns.
With this change, I noticed no major regression in either
Geekbench v3 or SPEC CPU2000 while some benchmarks, typically FP
ones, improved significantly.
I tested this tuning on Exynos M1 and on A57. ThunderX seems to
benefit from this tuning too. However, I'd appreciate comments
>from other stakeholders.
Ping.
I'd like to leave this for a call from the port maintainers. I can see why
this leads to more opportunities for vectorization, but I'm concerned about
the wider impact on code size. Certainly I wouldn't expect this to be our
default at -O2 and below.
My gut feeling is that this doesn't really belong in the back-end (there are
presumably good reasons why the default for this parameter across GCC has
fluctuated from 400 to 100 to 200 over recent years), but as I say, I'd
like Marcus or Richard to make the call as to whether or not we take this
patch.