public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/59644] [4.9 Regression] r206243 miscompiles Linux kernel
Date: Mon, 06 Jan 2014 11:55:00 -0000 [thread overview]
Message-ID: <bug-59644-4-zqpbY4QMg3@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-59644-4@http.gcc.gnu.org/bugzilla/>
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59644
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |vmakarov at gcc dot gnu.org
--- Comment #22 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
So, supposedly the:
10432 /* If drap has been set, but it actually isn't live at the
start
10433 of the function and !stack_realign, there is no reason to
set it up. */
10434 if (crtl->drap_reg && !stack_realign)
10435 {
10436 basic_block bb = ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb;
10437 if (! REGNO_REG_SET_P (DF_LR_IN (bb), REGNO
(crtl->drap_reg)))
10438 {
10439 crtl->drap_reg = NULL_RTX;
10440 crtl->need_drap = false;
10441 }
10442 }
hunk needs to be performed somewhere else (at the start of ira function, or
during reload/LRA (reload_in_progress/lra_in_progress) or not at all.
Supposedly the second crtl->drap_reg = NULL_RTX hunk in that function is fine,
because that is done only if there are no %rsp/%rbp accesses in the function.
And the ix86_save_reg change would need guarding by some other flag (a bit in *
cfun->machine ?) that would be set when ix86_finalize_stack_realign_flags
performed the optimization (but couldn't clear drap_reg because it was needed,
but wasn't needed to be preserved).
next prev parent reply other threads:[~2014-01-06 11:55 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-30 23:03 [Bug tree-optimization/59644] New: " trippels at gcc dot gnu.org
2013-12-30 23:43 ` [Bug tree-optimization/59644] " jakub at gcc dot gnu.org
2013-12-31 8:17 ` trippels at gcc dot gnu.org
2013-12-31 8:18 ` trippels at gcc dot gnu.org
2013-12-31 8:19 ` trippels at gcc dot gnu.org
2013-12-31 8:20 ` trippels at gcc dot gnu.org
2013-12-31 8:26 ` trippels at gcc dot gnu.org
2013-12-31 11:47 ` jakub at gcc dot gnu.org
2013-12-31 13:03 ` trippels at gcc dot gnu.org
2014-01-06 8:21 ` trippels at gcc dot gnu.org
2014-01-06 8:48 ` trippels at gcc dot gnu.org
2014-01-06 9:08 ` jakub at gcc dot gnu.org
2014-01-06 9:17 ` trippels at gcc dot gnu.org
2014-01-06 9:26 ` jakub at gcc dot gnu.org
2014-01-06 9:36 ` trippels at gcc dot gnu.org
2014-01-06 10:00 ` trippels at gcc dot gnu.org
2014-01-06 10:04 ` trippels at gcc dot gnu.org
2014-01-06 10:09 ` hjl.tools at gmail dot com
2014-01-06 10:12 ` jakub at gcc dot gnu.org
2014-01-06 10:21 ` trippels at gcc dot gnu.org
2014-01-06 11:28 ` jakub at gcc dot gnu.org
2014-01-06 11:55 ` jakub at gcc dot gnu.org [this message]
2014-01-06 13:39 ` [Bug target/59644] " jakub at gcc dot gnu.org
2014-01-06 21:38 ` jakub at gcc dot gnu.org
2014-01-06 21:39 ` 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-59644-4-zqpbY4QMg3@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).