public inbox for gcc-bugs@sourceware.org help / color / mirror / Atom feed
From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug tree-optimization/111694] [13/14 Regression] Wrong behavior for signbit of negative zero when optimizing Date: Wed, 04 Oct 2023 19:09:25 +0000 [thread overview] Message-ID: <bug-111694-4-8CSeoEgzgo@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-111694-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111694 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target Milestone|--- |13.3 Ever confirmed|0 |1 Last reconfirmed| |2023-10-04 Status|UNCONFIRMED |NEW --- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Confirmed. EVRP removes the second __bultin_signbit incorrectly. Most likely due to: ``` Folding statement: if (_3 != 0) Registering value_relation (l_11(D) == r_12(D)) on (2->3) ``` which then we get: ``` Predicate evaluates to: DON'T KNOW Matching expression match.pd:2679, gimple-match-2.cc:35 Matching expression match.pd:2682, gimple-match-1.cc:66 Matching expression match.pd:2689, gimple-match-2.cc:96 Not folded Folding statement: _20 = __builtin_signbit (r_12(D)); Queued stmt for removal. Folds to: 0 Folding statement: if (_20 != 0) gimple_simplified to if (0 != 0) gimple_simplified to if (0 != 0) Folded into: if (0 != 0) ``` For -O1 DOM does: ``` 1>>> STMT 1 = _8 le_expr 0 1>>> STMT 1 = _8 ge_expr 0 1>>> STMT 1 = _8 eq_expr 0 1>>> STMT 0 = _8 ne_expr 0 0>>> COPY _8 = 0 Optimizing statement _10 = __builtin_signbit (r_6(D)); Replaced 'r_6(D)' with constant '0.0' gimple_simplified to _10 = 0; Folded to: _10 = 0; LKUP STMT _10 = 0 ==== ASGN _10 = 0 Optimizing statement if (_10 != 0) Replaced '_10' with constant '0' gimple_simplified to if (0 != 0) Folded to: if (0 != 0) LKUP STMT 0 ne_expr 0 <<<< STMT 0 = _8 ne_expr 0 <<<< STMT 1 = _8 eq_expr 0 <<<< STMT 1 = _8 ge_expr 0 <<<< STMT 1 = _8 le_expr 0 <<<< COPY _8 = 0 ``` Which is wrong too.
next prev parent reply other threads:[~2023-10-04 19:09 UTC|newest] Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-10-04 17:09 [Bug web/111694] New: " alonzakai at gmail dot com 2023-10-04 18:31 ` [Bug tree-optimization/111694] [13/14 Regression] " amonakov at gcc dot gnu.org 2023-10-04 19:09 ` pinskia at gcc dot gnu.org [this message] 2023-10-05 7:37 ` rguenth at gcc dot gnu.org 2023-10-06 17:30 ` amacleod at redhat dot com 2023-10-09 17:10 ` cvs-commit at gcc dot gnu.org 2023-10-09 17:11 ` amacleod at redhat dot com 2023-10-09 17:18 ` amonakov at gcc dot gnu.org 2023-10-09 17:36 ` amacleod at redhat dot com 2023-10-09 19:37 ` amacleod at redhat dot com 2023-10-11 20:45 ` cvs-commit at gcc dot gnu.org 2023-10-11 20:48 ` amacleod at redhat dot com
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-111694-4-8CSeoEgzgo@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).