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* [Bug middle-end/18045] New: Wrong code for signed integer remainder
@ 2004-10-18 12:06 ebotcazou at gcc dot gnu dot org
2004-10-18 12:48 ` [Bug middle-end/18045] [4.0 Regression] signed integer remainder for power of 2 broken pinskia at gcc dot gnu dot org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2004-10-18 12:06 UTC (permalink / raw)
To: gcc-bugs
The following testcase:
extern void abort(void);
long long smod16(long long x)
{
return x % 16;
}
int main(void)
{
if (smod16 (0xFFFFFFFF) != 0xF)
abort ();
return 0;
}
distilled from ada/uintp.adb:UI_From_Dint is miscompiled on i486 because of
2004-06-27 Roger Sayle <roger@eyesopen.com>
* expmed.c (expand_smod_pow2): New function to expand signed
remainder by a constant power of 2, such as "x % 16".
(expand_divmod): Call new expand_smod_pow2 when appropriate.
Minor corrections to comments, e.g. splitting long lines.
The second part of expand_smod_pow2 cannot handle modes whose size is greater
than that of HOST_WIDE_INT.
--
Summary: Wrong code for signed integer remainder
Product: gcc
Version: 4.0.0
Status: UNCONFIRMED
Severity: critical
Priority: P2
Component: middle-end
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: ebotcazou at gcc dot gnu dot org
CC: gcc-bugs at gcc dot gnu dot org
GCC build triplet: i486-*-*
GCC host triplet: i486-*-*
GCC target triplet: i486-*-*
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18045
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/18045] [4.0 Regression] signed integer remainder for power of 2 broken
2004-10-18 12:06 [Bug middle-end/18045] New: Wrong code for signed integer remainder ebotcazou at gcc dot gnu dot org
@ 2004-10-18 12:48 ` pinskia at gcc dot gnu dot org
2004-10-18 12:56 ` pinskia at gcc dot gnu dot org
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-10-18 12:48 UTC (permalink / raw)
To: gcc-bugs
--
What |Removed |Added
----------------------------------------------------------------------------
CC| |roger at eyesopen dot com
Keywords| |wrong-code
Summary|Wrong code for signed |[4.0 Regression] signed
|integer remainder |integer remainder for power
| |of 2 broken
Target Milestone|--- |4.0.0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18045
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/18045] [4.0 Regression] signed integer remainder for power of 2 broken
2004-10-18 12:06 [Bug middle-end/18045] New: Wrong code for signed integer remainder ebotcazou at gcc dot gnu dot org
2004-10-18 12:48 ` [Bug middle-end/18045] [4.0 Regression] signed integer remainder for power of 2 broken pinskia at gcc dot gnu dot org
@ 2004-10-18 12:56 ` pinskia at gcc dot gnu dot org
2004-10-18 13:45 ` ebotcazou at gcc dot gnu dot org
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2004-10-18 12:56 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From pinskia at gcc dot gnu dot org 2004-10-18 12:56 -------
Confirmed (-march=i486 will show the bug on i686-*).
--
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed| |1
Known to fail| |4.0.0
Known to work| |3.4.0
Last reconfirmed|0000-00-00 00:00:00 |2004-10-18 12:56:35
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18045
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/18045] [4.0 Regression] signed integer remainder for power of 2 broken
2004-10-18 12:06 [Bug middle-end/18045] New: Wrong code for signed integer remainder ebotcazou at gcc dot gnu dot org
2004-10-18 12:48 ` [Bug middle-end/18045] [4.0 Regression] signed integer remainder for power of 2 broken pinskia at gcc dot gnu dot org
2004-10-18 12:56 ` pinskia at gcc dot gnu dot org
@ 2004-10-18 13:45 ` ebotcazou at gcc dot gnu dot org
2004-10-18 22:45 ` cvs-commit at gcc dot gnu dot org
2004-10-18 22:47 ` ebotcazou at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2004-10-18 13:45 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From ebotcazou at gcc dot gnu dot org 2004-10-18 13:44 -------
Thanks for confirming (I think -mtune=i486 is sufficient). Patch in testing.
--
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |ebotcazou at gcc dot gnu dot
|dot org |org
Status|NEW |ASSIGNED
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18045
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/18045] [4.0 Regression] signed integer remainder for power of 2 broken
2004-10-18 12:06 [Bug middle-end/18045] New: Wrong code for signed integer remainder ebotcazou at gcc dot gnu dot org
` (2 preceding siblings ...)
2004-10-18 13:45 ` ebotcazou at gcc dot gnu dot org
@ 2004-10-18 22:45 ` cvs-commit at gcc dot gnu dot org
2004-10-18 22:47 ` ebotcazou at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: cvs-commit at gcc dot gnu dot org @ 2004-10-18 22:45 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From cvs-commit at gcc dot gnu dot org 2004-10-18 22:45 -------
Subject: Bug 18045
CVSROOT: /cvs/gcc
Module name: gcc
Changes by: ebotcazou@gcc.gnu.org 2004-10-18 22:45:01
Modified files:
gcc : ChangeLog expmed.c
gcc/testsuite : ChangeLog
Added files:
gcc/testsuite/gcc.dg: smod-1.c
Log message:
PR middle-end/18045
* expmed.c (expand_smod_pow2): Handle modes whose size
is greater than that of HOST_WIDE_INT.
Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/ChangeLog.diff?cvsroot=gcc&r1=2.5940&r2=2.5941
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/expmed.c.diff?cvsroot=gcc&r1=1.198&r2=1.199
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.4472&r2=1.4473
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.dg/smod-1.c.diff?cvsroot=gcc&r1=NONE&r2=1.1
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18045
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/18045] [4.0 Regression] signed integer remainder for power of 2 broken
2004-10-18 12:06 [Bug middle-end/18045] New: Wrong code for signed integer remainder ebotcazou at gcc dot gnu dot org
` (3 preceding siblings ...)
2004-10-18 22:45 ` cvs-commit at gcc dot gnu dot org
@ 2004-10-18 22:47 ` ebotcazou at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: ebotcazou at gcc dot gnu dot org @ 2004-10-18 22:47 UTC (permalink / raw)
To: gcc-bugs
------- Additional Comments From ebotcazou at gcc dot gnu dot org 2004-10-18 22:47 -------
See http://gcc.gnu.org/ml/gcc-patches/2004-10/msg01571.html
--
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Resolution| |FIXED
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18045
^ permalink raw reply [flat|nested] 6+ messages in thread
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2004-10-18 12:06 [Bug middle-end/18045] New: Wrong code for signed integer remainder ebotcazou at gcc dot gnu dot org
2004-10-18 12:48 ` [Bug middle-end/18045] [4.0 Regression] signed integer remainder for power of 2 broken pinskia at gcc dot gnu dot org
2004-10-18 12:56 ` pinskia at gcc dot gnu dot org
2004-10-18 13:45 ` ebotcazou at gcc dot gnu dot org
2004-10-18 22:45 ` cvs-commit at gcc dot gnu dot org
2004-10-18 22:47 ` ebotcazou at gcc dot gnu dot org
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