public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug target/107259] New: Vectorize VxHF _Float16 modes using partial vectors without -mavx512vl
@ 2022-10-14 9:06 ubizjak at gmail dot com
2022-10-14 9:24 ` [Bug target/107259] " rguenth at gcc dot gnu.org
0 siblings, 1 reply; 2+ messages in thread
From: ubizjak at gmail dot com @ 2022-10-14 9:06 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107259
Bug ID: 107259
Summary: Vectorize VxHF _Float16 modes using partial vectors
without -mavx512vl
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: ubizjak at gmail dot com
Target Milestone: ---
The following testcase:
--cut here--
#define N 16
_Float16 r[N], a[N], b[N];
void foo (void)
{
for (int i = 0; i < N; i++)
r[i] = a[i] + b[i];
}
--cut here--
can be vectorized with -O2 -mavx512fp16 -mavx512vl, but not when -mavx512vl is
omitted. However, the test can still be vectorized using partial vectors.
The testcase should be vectorized for all N < 32, even without -mavx512vl.
^ permalink raw reply [flat|nested] 2+ messages in thread
* [Bug target/107259] Vectorize VxHF _Float16 modes using partial vectors without -mavx512vl
2022-10-14 9:06 [Bug target/107259] New: Vectorize VxHF _Float16 modes using partial vectors without -mavx512vl ubizjak at gmail dot com
@ 2022-10-14 9:24 ` rguenth at gcc dot gnu.org
0 siblings, 0 replies; 2+ messages in thread
From: rguenth at gcc dot gnu.org @ 2022-10-14 9:24 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107259
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target| |x86_64-*-*
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
The question is whether the backend should announce "VL" support and fixup
using masks transparently?
The vectorizer at the moment would require a fully masked loop (it doesn't
support the special case of loop vectorizing just the "last" iteration as
masked). The SLP vectorizer does not consider using masked larger vectors
either.
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2022-10-14 9:24 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-10-14 9:06 [Bug target/107259] New: Vectorize VxHF _Float16 modes using partial vectors without -mavx512vl ubizjak at gmail dot com
2022-10-14 9:24 ` [Bug target/107259] " rguenth at gcc dot gnu.org
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).