public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "rearnsha at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/42509] [4.5 Regression] bootstrap failure in stage3 (integer overflow in preprocessor expression)
Date: Thu, 01 Apr 2010 15:03:00 -0000 [thread overview]
Message-ID: <20100401150236.820.qmail@sourceware.org> (raw)
In-Reply-To: <bug-42509-11764@http.gcc.gnu.org/bugzilla/>
------- Comment #9 from rearnsha at gcc dot gnu dot org 2010-04-01 15:02 -------
This is a miscompilation during stage2. The file libcpp/expr.c is miscompiled.
The problem is occurring in num_positive, which ends up generating a shift of a
long long right by 63. The code generated is creating spills that are of
SImode variables for the shift output, but then the result is being loaded back
as a DImode object.
Due to scheduling, one of the stores is being moved incorrectly after the load
and we get the following assembly fragment:
342c: fa2b fb02 lsr.w fp, fp, r2
3430: fa0c f003 lsl.w r0, ip, r3
3434: fa2c f301 lsr.w r3, ip, r1
3438: fa2c f202 lsr.w r2, ip, r2
343c: ea40 000b orr.w r0, r0, fp
3440: 9245 str r2, [sp, #276] ; 0x114 <- first part
of store
3442: 4686 mov lr, r0
3444: 2201 movs r2, #1
3446: ea1e 0e21 ands.w lr, lr, r1, asr #32
344a: bf38 it cc
344c: 469e movcc lr, r3
344e: a944 add r1, sp, #272 ; 0x110
3450: e9d1 0100 ldrd r0, r1, [r1] <- Load back
3454: 2300 movs r3, #0
3456: f8cd e110 str.w lr, [sp, #272] ; 0x110 <- Second part
(oops, too late).
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42509
next prev parent reply other threads:[~2010-04-01 15:03 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-12-26 12:03 [Bug target/42509] New: " doko at ubuntu dot com
2009-12-29 10:09 ` [Bug target/42509] " ramana at gcc dot gnu dot org
2009-12-30 23:55 ` ramana at gcc dot gnu dot org
2009-12-31 15:21 ` [Bug target/42509] [4.5 Regression] " rguenth at gcc dot gnu dot org
2010-01-06 12:26 ` ramana at gcc dot gnu dot org
2010-01-07 13:53 ` debian-gcc at lists dot debian dot org
2010-03-15 13:23 ` rguenth at gcc dot gnu dot org
2010-03-15 17:36 ` laurent at guerby dot net
2010-03-16 8:57 ` ramana at gcc dot gnu dot org
2010-03-16 13:56 ` rguenth at gcc dot gnu dot org
2010-04-01 15:03 ` rearnsha at gcc dot gnu dot org [this message]
2010-04-01 15:11 ` rearnsha at gcc dot gnu dot org
2010-04-01 15:32 ` rearnsha at gcc dot gnu dot org
2010-04-01 15:55 ` ramana at gcc dot gnu dot org
2010-04-01 17:11 ` ramana at gcc dot gnu dot org
2010-04-01 19:31 ` rearnsha at gcc dot gnu dot org
2010-04-01 22:04 ` rearnsha at gcc dot gnu dot org
2010-04-01 22:44 ` rearnsha at gcc dot gnu dot org
2010-04-01 23:34 ` [Bug middle-end/42509] " rearnsha at gcc dot gnu dot org
2010-04-02 0:02 ` ramana at gcc dot gnu dot org
2010-04-02 8:08 ` ramana at gcc dot gnu dot org
2010-04-02 12:09 ` rguenth at gcc dot gnu dot org
2010-04-02 12:15 ` rguenth at gcc dot gnu dot org
2010-04-02 12:33 ` rguenth at gcc dot gnu dot org
2010-04-02 13:54 ` rguenth at gcc dot gnu dot org
2010-04-02 15:20 ` rguenth at gcc dot gnu dot org
2010-04-02 16:15 ` rguenth at gcc dot gnu dot org
2010-04-03 17:15 ` rguenth at gcc dot gnu dot org
2010-04-03 17:15 ` rguenth at gcc dot gnu dot org
2010-04-12 19:56 ` [Bug middle-end/42509] [4.4 " steven at gcc dot gnu dot org
2010-04-12 19:58 ` [Bug middle-end/42509] [4.4 Regression] nonoverlapping_memrefs_p misinterprets NULL MEM_OFFSET as const0_rtx steven at gcc dot gnu dot org
2010-04-30 8:58 ` jakub at gcc dot gnu dot org
2010-07-28 18:00 ` uweigand at gcc dot gnu dot org
2010-07-28 18:01 ` uweigand at gcc dot gnu dot 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=20100401150236.820.qmail@sourceware.org \
--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).