public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "andres at anarazel dot de" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/106590] New: x86-64 miscompilation starting with "i386: Improve ix86_expand_int_movcc" w/ mtune=skylake Date: Fri, 12 Aug 2022 04:23:25 +0000 [thread overview] Message-ID: <bug-106590-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106590 Bug ID: 106590 Summary: x86-64 miscompilation starting with "i386: Improve ix86_expand_int_movcc" w/ mtune=skylake Product: gcc Version: 12.1.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: andres at anarazel dot de Target Milestone: --- Hi, The attached reproducer shows a miscompilation I found building postgres. I've bisected postgres' failure to 1ceddd7497e, but it's of course possible it's just surfacing a prior issue. In my reproducer, and in postgres, the problem only occurs with -mtune=skylake or higher, but I'm not sure how related that actually is. $ /home/andres/build/gcc-master/install/bin/gcc --version gcc (GCC) 12.0.1 20220423 (experimental) Copyright (C) 2022 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ gcc-11 --version gcc-11 (Debian 11.3.0-5) 11.3.0 Copyright (C) 2021 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ /home/andres/build/gcc-master/install/bin/gcc -Wall -Wextra -O1 -mtune=skylake /tmp/test.i -o /tmp/test $ /tmp/test wrong results: procform->prorettype: 23, restype: 20 $ /home/andres/build/gcc-master/install/bin/gcc -Wall -Wextra -O1 -mtune=broadwell /tmp/test.i -o /tmp/test $ /tmp/test everything ok: procform->prorettype: 23, restype: 23 $ gcc-11 -Wall -Wextra -O1 -mtune=skylake /tmp/test.i -o /tmp/test $ /tmp/test everything ok: procform->prorettype: 23, restype: 23 I think it's pretty obvious that the code should never be able to result in restype == 20. Regards, Andres
next reply other threads:[~2022-08-12 4:23 UTC|newest] Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-08-12 4:23 andres at anarazel dot de [this message] 2022-08-12 4:23 ` [Bug target/106590] " andres at anarazel dot de 2022-08-12 4:37 ` [Bug target/106590] [12/13 Regression] " pinskia at gcc dot gnu.org 2022-08-12 4:38 ` pinskia at gcc dot gnu.org 2022-08-12 4:52 ` [Bug rtl-optimization/106590] [12/13 Regression] x86-64 miscompilation starting with r12-8233-g1ceddd7497e15d " pinskia at gcc dot gnu.org 2022-08-12 4:53 ` pinskia at gcc dot gnu.org 2022-08-12 4:59 ` pinskia at gcc dot gnu.org 2022-08-12 6:40 ` rguenth at gcc dot gnu.org 2022-08-12 13:47 ` jakub at gcc dot gnu.org 2022-08-12 14:46 ` jakub at gcc dot gnu.org 2022-08-15 11:57 ` cvs-commit at gcc dot gnu.org 2022-08-15 12:00 ` jakub at gcc dot gnu.org 2022-08-29 10:05 ` cvs-commit at gcc dot gnu.org 2022-08-30 9:11 ` jakub 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-106590-4@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: linkBe 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).