This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug tree-optimization/81303] New: [8 Regression] 410.bwaves regression caused by r249919
- From: "rguenth at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: Tue, 04 Jul 2017 08:06:00 +0000
- Subject: [Bug tree-optimization/81303] New: [8 Regression] 410.bwaves regression caused by r249919
- Auto-submitted: auto-generated
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81303
Bug ID: 81303
Summary: [8 Regression] 410.bwaves regression caused by r249919
Product: gcc
Version: 8.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: rguenth at gcc dot gnu.org
Target Milestone: ---
I see on Haswell with -march=native -Ofast a runtime increase from 177s to
254s.
This is caused by us vectorizing the innermost reduction loop in
block_solver.f:mat_times_vec using strided loads (and with -mprefer-avx128 even
peeling for alignment).