https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124536
Bug ID: 124536
Summary: 3-8% slowdown of exchange2_r on Zen* since
r16-8005-g0619a560b9486a
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: jmelcr at gcc dot gnu.org
CC: law at gcc dot gnu.org, pheeck at gcc dot gnu.org
Blocks: 26163
Target Milestone: ---
One of the fixes for PR90036 (r16-7825-gf23a339a686ed6) sped up the exchange2_r
SPEC 2017 benchmark across all of our Zen machines. r16-8005-g0619a560b9486a
reverts the said commit. Is there a way to get that speed up back?
Graphs:
znver2 -O2 -g -flto=128
https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=298.407.0
znver2 -O2 -march=native -g -flto=128
https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=296.407.0
znver3 -O2 -march=native -g -flto=128
https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=462.407.0
znver4 -O2 -g -flto=128 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3
-fstack-protector-strong -funwind-tables -fasynchronous-unwind-tables
-fstack-clash-protection
https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=1103.407.0
znver5 -O2 -march=x86-64-v3 -g -flto=128
https://lnt.opensuse.org/db_default/v4/SPEC/graph?plot.0=1249.407.0
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=26163
[Bug 26163] [meta-bug] missed optimization in SPEC (2k17, 2k and 2k6 and 95)
