https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116397
Bug ID: 116397
Summary: [15 Regression] slp-reduc-3.c fails on
aarch64-linux-gnu
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Keywords: testsuite-fail
Severity: normal
Priority: P3
Component: testsuite
Assignee: unassigned at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
Target: aarch64-linux-gnu
>From https://gcc.gnu.org/pipermail/gcc-patches/2024-May/652829.html:
On aarch64 and arm there's
FAIL: gcc.dg/vect/slp-reduc-3.c scan-tree-dump-times vect "VEC_PERM_EXPR"
0
which is a testism, I _think_ due to a bogus vect_load_lanes check
in that line. The code is as expected not using a SLP reduction of
two lanes due to the widen-sum pattern used. It might be that we
somehow fail to use load-lanes when vectorizing the load with SLP
which means that for SLP reductions we fail to consider
load-lanes as override. I think we should leave this FAIL, we need to
work to get load-lanes vectorization from SLP anyway. To fix this
the load-permutation followup I have in the works will be necessary.
