[Bug tree-optimization/72517] [7 Regression] 436.cactusADM: More than 40% regression in O3 and Ofast on AMD bdver4 m/c.

["rguenth at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72517

--- Comment #13 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to rguenther@suse.de from comment #12)
> On July 27, 2016 7:02:07 PM GMT+02:00, "Amit.Pawar at amd dot com"
> <gcc-bugzilla@gcc.gnu.org> wrote:
> >https://gcc.gnu.org/bugzilla/show_bug.cgi?id=72517
> >
> >--- Comment #11 from Amit Pawar <Amit.Pawar at amd dot com> ---
> >Improvement is seen but not same as best one. 
> >
> >
> >Current scores are
> >Flags           Latest trunk
> >O3                  :31.4
> >O3 -march=bdver4    :31.1
> >Ofast               :32.1
> >Ofast -march=bdver4 :31.2
> >
> >but good one.
> >Flags           Good Trunk
> >O3              37.69           
> >O3 bdver4       36.55           
> >Ofast           40.36
> >Ofast bdver4    38.31
> >
> >Can you please check at your end?
> 
> I checked r237473 plus the patch against r237472 and the regression was
> fully fixed.  I did not yet check current trunk but if there is any
> regression it is a new one caused by sth else.  Bisection with the fix for
> this regression might tell.

Double-checking against trunk, thus base is r237472 and peak is r238807 I get

436.cactusADM   11950        320       37.3 *   11950        318       37.5 *  

for -Ofast -march=native (three-run result).  This is FAM 21 Model 96 Stepping
1 detected as bdver4 by GCC.