public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "rguenther at suse dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/110237] gcc.dg/torture/pr58955-2.c is miscompiled by RTL scheduling after reload
Date: Tue, 20 Jun 2023 12:20:04 +0000 [thread overview]
Message-ID: <bug-110237-4-YoqWO4vwkV@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-110237-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110237
--- Comment #5 from rguenther at suse dot de <rguenther at suse dot de> ---
On Tue, 20 Jun 2023, crazylht at gmail dot com wrote:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110237
>
> --- Comment #4 from Hongtao.liu <crazylht at gmail dot com> ---
> (In reply to Richard Biener from comment #3)
> > This looks like the same issue as PR110309. We have
> >
> > (insn 38 35 39 3 (set (mem:V16SI (plus:DI (reg:DI 40 r12 [orig:90 _22 ] [90])
> > (const:DI (plus:DI (symbol_ref:DI ("b") [flags 0x2]
> > <var_decl 0x7ffff6e28d80 b>)
> > (const_int -4 [0xfffffffffffffffc])))) [1 MEM
> > <vector(16) int> [(int *)vectp_b.12_28]+0 S64 A32])
> > (vec_merge:V16SI (reg:V16SI 20 xmm0 [118])
> > (mem:V16SI (plus:DI (reg:DI 40 r12 [orig:90 _22 ] [90])
> > (const:DI (plus:DI (symbol_ref:DI ("b") [flags 0x2]
> > <var_decl 0x7ffff6e28d80 b>)
> > (const_int -4 [0xfffffffffffffffc])))) [1 MEM
> > <vector(16) int> [(int *)vectp_b.12_28]+0 S64 A32])
> >
> > so instead of a masked load we see a vec_merge with a (mem:V16SI ...)
> > based on the vectp_b.12_28 pointer that has full size but the load of b[1]
> > we try disambiguate against refers to int b[10] which is too small for
> > a load of 64 bytes so we disambiguate based on that.
>
>
> /* If the pointer based access is bigger than the variable they cannot
> alias. This is similar to the check below where we use TBAA to
> increase the size of the pointer based access based on the dynamic
> type of a containing object we can infer from it. */
> poly_int64 dsize2;
> if (known_size_p (size1) --- should be unknown??
> && poly_int_tree_p (DECL_SIZE (base2), &dsize2)
> && known_lt (dsize2, size1))
> return false;
>
> Should we set MEM_SIZE_KNOWN_P to false for maskstore/maskload?
> It seems to me maxsize should be 64bytes, but real size should be unknown.
Yes, you shouldn't have MEM_ATTRs that indicate the size is known.
next prev parent reply other threads:[~2023-06-20 12:20 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-13 13:50 [Bug rtl-optimization/110237] New: " rguenth at gcc dot gnu.org
2023-06-14 11:02 ` [Bug rtl-optimization/110237] " amonakov at gcc dot gnu.org
2023-06-14 12:09 ` rguenth at gcc dot gnu.org
2023-06-20 9:52 ` rguenth at gcc dot gnu.org
2023-06-20 11:35 ` crazylht at gmail dot com
2023-06-20 12:20 ` rguenther at suse dot de [this message]
2023-06-20 16:05 ` crazylht at gmail dot com
2023-06-21 5:48 ` crazylht at gmail dot com
2023-06-21 7:33 ` rguenth at gcc dot gnu.org
2023-06-25 4:06 ` crazylht at gmail dot com
2023-06-26 7:41 ` rguenther at suse dot de
2023-06-26 7:58 ` amonakov at gcc dot gnu.org
2023-06-26 8:07 ` rguenther at suse dot de
2023-06-26 8:22 ` amonakov at gcc dot gnu.org
2023-06-26 8:35 ` rguenther at suse dot de
2023-06-26 8:44 ` crazylht at gmail dot com
2023-06-26 8:54 ` amonakov at gcc dot gnu.org
2023-06-26 11:14 ` rguenther at suse dot de
2023-06-26 18:19 ` amonakov at gcc dot gnu.org
2023-06-27 6:53 ` rguenther at suse dot de
2023-06-27 7:30 ` cvs-commit at gcc dot gnu.org
2023-06-27 9:50 ` amonakov at gcc dot gnu.org
2023-06-27 10:03 ` rguenther at suse dot de
2023-06-29 1:27 ` cvs-commit at gcc dot gnu.org
2023-06-29 1:28 ` cvs-commit at gcc dot gnu.org
2023-06-29 1:29 ` cvs-commit at gcc dot gnu.org
2023-11-27 12:39 ` rdapp at gcc dot gnu.org
2023-11-29 12:26 ` cvs-commit at gcc dot gnu.org
2023-11-29 12:27 ` rguenth at gcc dot gnu.org
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=bug-110237-4-YoqWO4vwkV@http.gcc.gnu.org/bugzilla/ \
--to=gcc-bugzilla@gcc.gnu.org \
--cc=gcc-bugs@gcc.gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).