public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "ebotcazou at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/104356] [12 Regression] divide by zero trap is being removed now when it should not be in some cases
Date: Thu, 03 Feb 2022 11:48:01 +0000 [thread overview]
Message-ID: <bug-104356-4-d1eWGCLNh9@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-104356-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104356
--- Comment #14 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> OK, so a division by zero is not invoking undefined behavior but is
> well-defined and traps. And the idea is that -fnon-call-exceptions alone
> carries this over to middle-end semantics? (I don't think it does that at
> the moment, with or without the rev. in question)
Why? It's exactly like any other trapping operation, see the numerous
predicates in tree-eh.cc, most notably operation_could_trap_helper_p:
switch (op)
{
case TRUNC_DIV_EXPR:
case CEIL_DIV_EXPR:
case FLOOR_DIV_EXPR:
case ROUND_DIV_EXPR:
case EXACT_DIV_EXPR:
case CEIL_MOD_EXPR:
case FLOOR_MOD_EXPR:
case ROUND_MOD_EXPR:
case TRUNC_MOD_EXPR:
if (!TREE_CONSTANT (divisor) || integer_zerop (divisor))
return true;
next prev parent reply other threads:[~2022-02-03 11:48 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-02 22:56 [Bug tree-optimization/104356] New: " pinskia at gcc dot gnu.org
2022-02-02 22:57 ` [Bug tree-optimization/104356] " pinskia at gcc dot gnu.org
2022-02-02 23:08 ` jakub at gcc dot gnu.org
2022-02-03 7:32 ` rguenth at gcc dot gnu.org
2022-02-03 7:42 ` pinskia at gcc dot gnu.org
2022-02-03 7:43 ` pinskia at gcc dot gnu.org
2022-02-03 7:58 ` pinskia at gcc dot gnu.org
2022-02-03 8:34 ` rguenther at suse dot de
2022-02-03 10:40 ` ebotcazou at gcc dot gnu.org
2022-02-03 11:08 ` rguenther at suse dot de
2022-02-03 11:14 ` ebotcazou at gcc dot gnu.org
2022-02-03 11:22 ` jakub at gcc dot gnu.org
2022-02-03 11:41 ` ebotcazou at gcc dot gnu.org
2022-02-03 11:43 ` rguenth at gcc dot gnu.org
2022-02-03 11:45 ` jakub at gcc dot gnu.org
2022-02-03 11:48 ` ebotcazou at gcc dot gnu.org [this message]
2022-02-03 11:50 ` ebotcazou at gcc dot gnu.org
2022-02-03 11:52 ` rguenth at gcc dot gnu.org
2022-02-03 11:56 ` rguenth at gcc dot gnu.org
2022-02-03 12:00 ` rguenth at gcc dot gnu.org
2022-02-03 12:00 ` jakub at gcc dot gnu.org
2022-02-03 12:03 ` jakub at gcc dot gnu.org
2022-02-03 12:03 ` ebotcazou at gcc dot gnu.org
2022-02-03 12:05 ` ebotcazou at gcc dot gnu.org
2022-02-03 12:05 ` rguenther at suse dot de
2022-02-03 12:10 ` rguenth at gcc dot gnu.org
2022-02-03 12:13 ` jakub at gcc dot gnu.org
2022-02-03 12:18 ` ebotcazou at gcc dot gnu.org
2022-02-03 12:21 ` cvs-commit at gcc dot gnu.org
2022-02-03 12:28 ` ebotcazou at gcc dot gnu.org
2022-02-03 12:39 ` jakub at gcc dot gnu.org
2022-02-03 12:49 ` ebotcazou at gcc dot gnu.org
2022-02-03 12:51 ` ebotcazou at gcc dot gnu.org
2022-02-03 13:04 ` jakub at gcc dot gnu.org
2022-02-03 13:09 ` rguenther at suse dot de
2022-02-03 15:41 ` ebotcazou at gcc dot gnu.org
2022-02-03 16:28 ` [Bug tree-optimization/104356] [12 Regression] divide by zero trap incorrectly optimized away jakub at gcc dot gnu.org
2022-02-03 16:41 ` ebotcazou at gcc dot gnu.org
2022-02-03 16:51 ` amacleod at redhat dot com
2022-02-03 16:57 ` jakub at gcc dot gnu.org
2022-02-03 18:35 ` amacleod at redhat dot com
2022-02-04 7:08 ` rguenther at suse dot de
2022-02-04 7:11 ` rguenth at gcc dot gnu.org
2022-02-04 10:05 ` ebotcazou at gcc dot gnu.org
2022-02-04 11:10 ` cvs-commit at gcc dot gnu.org
2022-02-04 11:17 ` ebotcazou at gcc dot gnu.org
2022-02-04 13:46 ` amacleod at redhat dot com
2022-02-04 16:40 ` ebotcazou at gcc dot gnu.org
2022-02-04 16:45 ` cvs-commit 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-104356-4-d1eWGCLNh9@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).