[Bug middle-end/112697] [14 Regression] 30-40% exec time regression of 433.milc on zen2 since r14-4972-g8aa47713701b1f

[jamborm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112697

--- Comment #6 from Martin Jambor <jamborm at gcc dot gnu.org> ---
Created attachment 56719
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=56719&action=edit
Perf annotate of milc built with r14-4971-g0beb1611754742

commit r14-4971-g0beb1611754742:

$ perf stat taskset -c 0 specinvoke

 Performance counter stats for 'taskset -c 0 specinvoke':

         216908.59 msec task-clock:u                     #    1.000 CPUs
utilized             
                 0      context-switches:u               #    0.000 /sec        
                 0      cpu-migrations:u                 #    0.000 /sec        
            889694      page-faults:u                    #    4.102 K/sec       
      697007650237      cycles:u                         #    3.213 GHz        
                (83.33%)
       31999772966      stalled-cycles-frontend:u        #    4.59% frontend
cycles idle        (83.33%)
      540485725923      stalled-cycles-backend:u         #   77.54% backend
cycles idle         (83.33%)
     1061256162815      instructions:u                   #    1.52  insn per
cycle            
                                                  #    0.51  stalled cycles per
insn     (83.33%)
       58760648879      branches:u                       #  270.901 M/sec      
                (83.34%)
          11890202      branch-misses:u                  #    0.02% of all
branches             (83.33%)

     216.935387643 seconds time elapsed

     211.436079000 seconds user
       5.472459000 seconds sys

$ perf record taskset -c 0 specinvoke
[ perf record: Woken up 132 times to write data ]
[ perf record: Captured and wrote 32.901 MB perf.data (862286 samples) ]


$ perf report -n --percent-limit=1 --stdio
# To display the perf.data header info, please use --header/--header-only
options.
#
#
# Total Lost Samples: 0
#
# Samples: 862K of event 'cycles:Pu'
# Event count (approx.): 695776598661
#
# Overhead       Samples  Command          Shared Object           Symbol       
# ........  ............  ...............  ...................... 
......................................
#
    22.68%        197003  milc_base.mine-  milc_base.mine-lto-gen  [.]
mult_su3_na
    20.99%        177912  milc_base.mine-  milc_base.mine-lto-gen  [.]
u_shift_fermion
    19.04%        163787  milc_base.mine-  milc_base.mine-lto-gen  [.]
mult_su3_nn
     6.85%         58509  milc_base.mine-  milc_base.mine-lto-gen  [.]
scalar_mult_add_su3_matrix
     5.51%         50953  milc_base.mine-  milc_base.mine-lto-gen  [.]
path_product
     5.40%         46083  milc_base.mine-  milc_base.mine-lto-gen  [.]
mult_su3_an
     4.22%         35853  milc_base.mine-  milc_base.mine-lto-gen  [.]
add_force_to_mom
     3.77%         32446  milc_base.mine-  milc_base.mine-lto-gen  [.]
imp_gauge_force.constprop.0
     1.98%         16848  milc_base.mine-  milc_base.mine-lto-gen  [.]
compute_gen_staple
     1.94%         16462  milc_base.mine-  milc_base.mine-lto-gen  [.]
make_anti_hermitian
     1.73%         14655  milc_base.mine-  milc_base.mine-lto-gen  [.]
mult_su3_mat_vec_sum_4dir
     1.35%         11472  milc_base.mine-  milc_base.mine-lto-gen  [.]
mult_adj_su3_mat_4vec
     1.27%         10801  milc_base.mine-  libc.so.6               [.]
__memset_avx2_unaligned_erms


$ perf annotate -n --percent-limit=1 > ~/tmp/milc-perf-annotate-0beb1611754 
(gzipeped and attached)