public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug tree-optimization/22630] New: vrp produces wrong code
@ 2005-07-23 16:35 belyshev at depni dot sinp dot msu dot ru
2005-07-23 16:36 ` [Bug tree-optimization/22630] " belyshev at depni dot sinp dot msu dot ru
` (7 more replies)
0 siblings, 8 replies; 9+ messages in thread
From: belyshev at depni dot sinp dot msu dot ru @ 2005-07-23 16:35 UTC (permalink / raw)
To: gcc-bugs
// C testcase, compile with -O2
// reduced from mozilla crashes in javascript library
void abort (void);
int j;
void bla (int *r)
{
int *p, *q;
p = q = r;
if (!p)
p = &j;
if (p != q)
j = 1;
}
int main (void)
{
bla (0);
if (!j)
abort ();
return 0;
}
--
Summary: vrp produces wrong code
Product: gcc
Version: 4.1.0
Status: UNCONFIRMED
Keywords: wrong-code
Severity: critical
Priority: P2
Component: tree-optimization
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: belyshev at depni dot sinp dot msu dot ru
CC: dnovillo at gcc dot gnu dot org,gcc-bugs at gcc dot gnu
dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22630
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/22630] vrp produces wrong code
2005-07-23 16:35 [Bug tree-optimization/22630] New: vrp produces wrong code belyshev at depni dot sinp dot msu dot ru
@ 2005-07-23 16:36 ` belyshev at depni dot sinp dot msu dot ru
2005-07-23 16:38 ` [Bug tree-optimization/22630] [4.1 Regression] " pinskia at gcc dot gnu dot org
` (6 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: belyshev at depni dot sinp dot msu dot ru @ 2005-07-23 16:36 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From belyshev at depni dot sinp dot msu dot ru 2005-07-23 16:35 -------
started to fail between "2005-06-02 00:20 UTC" and "2005-06-03 00:20 UTC"
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22630
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/22630] [4.1 Regression] vrp produces wrong code
2005-07-23 16:35 [Bug tree-optimization/22630] New: vrp produces wrong code belyshev at depni dot sinp dot msu dot ru
2005-07-23 16:36 ` [Bug tree-optimization/22630] " belyshev at depni dot sinp dot msu dot ru
@ 2005-07-23 16:38 ` pinskia at gcc dot gnu dot org
2005-07-23 17:07 ` pinskia at gcc dot gnu dot org
` (5 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-07-23 16:38 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2005-07-23 16:36 -------
Confirmed.
For some reason we fold:
Folding predicate p_1 != r_2 to 0
Folded statement: if (p_1 != r_2) goto <L2>; else goto <L3>;
into: if (0) goto <L2>; else goto <L3>;
p_1: ~[0B, 0B] EQUIVALENCES: { r_2 } (1 elements)
r_2: VARYING
q_3: [r_2, r_2] EQUIVALENCES: { r_2 } (1 elements)
p_4: [r_2, r_2] EQUIVALENCES: { r_2 } (1 elements)
r_7: ~[0B, 0B] EQUIVALENCES: { r_2 } (1 elements)
# p_1 = PHI <r_7(5), &j(1)>;
<L1>:;
--
What |Removed |Added
----------------------------------------------------------------------------
CC| |pinskia at gcc dot gnu dot
| |org
Status|UNCONFIRMED |NEW
Ever Confirmed| |1
Last reconfirmed|0000-00-00 00:00:00 |2005-07-23 16:36:51
date| |
Summary|vrp produces wrong code |[4.1 Regression] vrp
| |produces wrong code
Target Milestone|--- |4.1.0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22630
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/22630] [4.1 Regression] vrp produces wrong code
2005-07-23 16:35 [Bug tree-optimization/22630] New: vrp produces wrong code belyshev at depni dot sinp dot msu dot ru
2005-07-23 16:36 ` [Bug tree-optimization/22630] " belyshev at depni dot sinp dot msu dot ru
2005-07-23 16:38 ` [Bug tree-optimization/22630] [4.1 Regression] " pinskia at gcc dot gnu dot org
@ 2005-07-23 17:07 ` pinskia at gcc dot gnu dot org
2005-07-25 0:43 ` phython at gcc dot gnu dot org
` (4 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2005-07-23 17:07 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2005-07-23 16:38 -------
Caused almost likely by:
+2005-06-01 Diego Novillo <dnovillo@redhat.com>
+
+ PR 14341, PR 21332, PR 20701, PR 21029, PR 21086, PR 21090
+ PR 21289, PR 21348, PR 21367, PR 21368, PR 21458.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22630
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/22630] [4.1 Regression] vrp produces wrong code
2005-07-23 16:35 [Bug tree-optimization/22630] New: vrp produces wrong code belyshev at depni dot sinp dot msu dot ru
` (2 preceding siblings ...)
2005-07-23 17:07 ` pinskia at gcc dot gnu dot org
@ 2005-07-25 0:43 ` phython at gcc dot gnu dot org
2005-07-26 20:06 ` law at redhat dot com
` (3 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: phython at gcc dot gnu dot org @ 2005-07-25 0:43 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From phython at gcc dot gnu dot org 2005-07-25 00:35 -------
Calling vrp_evaluate_condition with use_equiv_p = false in tree-ssa-propagate.c
could fix this problem.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22630
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/22630] [4.1 Regression] vrp produces wrong code
2005-07-23 16:35 [Bug tree-optimization/22630] New: vrp produces wrong code belyshev at depni dot sinp dot msu dot ru
` (3 preceding siblings ...)
2005-07-25 0:43 ` phython at gcc dot gnu dot org
@ 2005-07-26 20:06 ` law at redhat dot com
2005-07-27 16:22 ` law at redhat dot com
` (2 subsequent siblings)
7 siblings, 0 replies; 9+ messages in thread
From: law at redhat dot com @ 2005-07-26 20:06 UTC (permalink / raw)
To: gcc-bugs
--
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |law at gcc dot gnu dot org
|dot org |
Status|NEW |ASSIGNED
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22630
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/22630] [4.1 Regression] vrp produces wrong code
2005-07-23 16:35 [Bug tree-optimization/22630] New: vrp produces wrong code belyshev at depni dot sinp dot msu dot ru
` (4 preceding siblings ...)
2005-07-26 20:06 ` law at redhat dot com
@ 2005-07-27 16:22 ` law at redhat dot com
2005-07-27 16:36 ` ja2morri at csclub dot uwaterloo dot ca
2005-07-27 17:06 ` law at redhat dot com
7 siblings, 0 replies; 9+ messages in thread
From: law at redhat dot com @ 2005-07-27 16:22 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From law at redhat dot com 2005-07-27 16:21 -------
Fixed by the attached patch.
--
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution| |FIXED
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22630
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/22630] [4.1 Regression] vrp produces wrong code
2005-07-23 16:35 [Bug tree-optimization/22630] New: vrp produces wrong code belyshev at depni dot sinp dot msu dot ru
` (5 preceding siblings ...)
2005-07-27 16:22 ` law at redhat dot com
@ 2005-07-27 16:36 ` ja2morri at csclub dot uwaterloo dot ca
2005-07-27 17:06 ` law at redhat dot com
7 siblings, 0 replies; 9+ messages in thread
From: ja2morri at csclub dot uwaterloo dot ca @ 2005-07-27 16:36 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From ja2morri at csclub dot uwaterloo dot ca 2005-07-27 16:34 -------
Subject: Re: [4.1 Regression] vrp produces
wrong code
Jeffrey A Law <law@redhat.com> writes:
> The underlying problem here is the code to meet a VR_ANTI_RANGE and
> a VR_RANGE does not intersect the equivalence sets. This in turn
> causes the VRP code to incorrectly evaluate a conditional. It's
> all downhill after that.
>
> While investigating this problem I also noticed that the vrp_meet
> code does not properly handle intersecting the equivalence sets
> when vr0 has a set, but vr1 does not (their intersection is the
> null set of course). This patch fixes that oversight as well.
>
> Bootstrapped and regression tested on i686-pc-linux-gnu.
>
> jeff
You added 3 bitmap_clear calls here, do you have any testcases that
exercise this code?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22630
^ permalink raw reply [flat|nested] 9+ messages in thread
* [Bug tree-optimization/22630] [4.1 Regression] vrp produces wrong code
2005-07-23 16:35 [Bug tree-optimization/22630] New: vrp produces wrong code belyshev at depni dot sinp dot msu dot ru
` (6 preceding siblings ...)
2005-07-27 16:36 ` ja2morri at csclub dot uwaterloo dot ca
@ 2005-07-27 17:06 ` law at redhat dot com
7 siblings, 0 replies; 9+ messages in thread
From: law at redhat dot com @ 2005-07-27 17:06 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From law at redhat dot com 2005-07-27 16:55 -------
Subject: Re: [4.1 Regression] vrp produces
wrong code
On Wed, 2005-07-27 at 16:34 +0000, ja2morri at csclub dot uwaterloo dot
ca wrote:
> ------- Additional Comments From ja2morri at csclub dot uwaterloo dot ca 2005-07-27 16:34 -------
> Subject: Re: [4.1 Regression] vrp produces
> wrong code
>
>
> Jeffrey A Law <law@redhat.com> writes:
>
> > The underlying problem here is the code to meet a VR_ANTI_RANGE and
> > a VR_RANGE does not intersect the equivalence sets. This in turn
> > causes the VRP code to incorrectly evaluate a conditional. It's
> > all downhill after that.
> >
> > While investigating this problem I also noticed that the vrp_meet
> > code does not properly handle intersecting the equivalence sets
> > when vr0 has a set, but vr1 does not (their intersection is the
> > null set of course). This patch fixes that oversight as well.
> >
> > Bootstrapped and regression tested on i686-pc-linux-gnu.
> >
> > jeff
>
> You added 3 bitmap_clear calls here, do you have any testcases that
> exercise this code?
No, but the code is clearly wrong by inspection.
jeff
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22630
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2005-07-27 16:56 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2005-07-23 16:35 [Bug tree-optimization/22630] New: vrp produces wrong code belyshev at depni dot sinp dot msu dot ru
2005-07-23 16:36 ` [Bug tree-optimization/22630] " belyshev at depni dot sinp dot msu dot ru
2005-07-23 16:38 ` [Bug tree-optimization/22630] [4.1 Regression] " pinskia at gcc dot gnu dot org
2005-07-23 17:07 ` pinskia at gcc dot gnu dot org
2005-07-25 0:43 ` phython at gcc dot gnu dot org
2005-07-26 20:06 ` law at redhat dot com
2005-07-27 16:22 ` law at redhat dot com
2005-07-27 16:36 ` ja2morri at csclub dot uwaterloo dot ca
2005-07-27 17:06 ` law at redhat dot com
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).