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* [Bug regression/26128] New: Regression vs 4.1.0cvs20051015 - Trivial operation not vectorized
@ 2006-02-06 14:55 hurbain at cri dot ensmp dot fr
2006-02-06 15:00 ` [Bug tree-optimization/26128] Trivial operation not vectorized on char pinskia at gcc dot gnu dot org
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: hurbain at cri dot ensmp dot fr @ 2006-02-06 14:55 UTC (permalink / raw)
To: gcc-bugs
char a[16] __attribute__((aligned)) = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
13, 14, 15, 16};
char b[16] __attribute__((aligned)) = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
13, 14, 15, 16};
char c[16] __attribute__((aligned));
int i;
for(i = 0; i<16; i++)
{
c[i] = a[i] + b[i];
}
for(i = 0; i<16; i++)
{
printf("%i ", c[i]);
}
This code is not vectorized anymore in GCC 4.2.0 (svn checkout on Feb, 06
2006). The vectorizer tells that :
paddb4bugreport.c:14: note: vect_is_simple_use: operand (unsigned char)
D.1872_47
paddb4bugreport.c:14: note: not ssa-name.
paddb4bugreport.c:14: note: use not simple.
paddb4bugreport.c:14: note: not vectorized: relevant stmt not supported:
D.1873_48 = (unsigned char) D.1872_47
paddb4bugreport.c:14: note: bad operation or unsupported loop
bound.(get_loop_exit_condition
if (ivtmp.52_2 != 0) goto <L13>; else goto <L5>;)
Seems to be a problem before the autovectorizer as the (unsigned char) cast
should not happen IMHO.
--
Summary: Regression vs 4.1.0cvs20051015 - Trivial operation not
vectorized
Product: gcc
Version: 4.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: regression
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: hurbain at cri dot ensmp dot fr
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26128
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug tree-optimization/26128] Trivial operation not vectorized on char
2006-02-06 14:55 [Bug regression/26128] New: Regression vs 4.1.0cvs20051015 - Trivial operation not vectorized hurbain at cri dot ensmp dot fr
@ 2006-02-06 15:00 ` pinskia at gcc dot gnu dot org
2006-09-21 17:12 ` pinskia at gcc dot gnu dot org
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-02-06 15:00 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from pinskia at gcc dot gnu dot org 2006-02-06 15:00 -------
Actually this is a known regression and a missed optimization regression caused
by fixing up wrong code.
The work around is to use -fwrapv.
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Severity|normal |enhancement
Status|UNCONFIRMED |NEW
Component|regression |tree-optimization
Ever Confirmed|0 |1
Keywords| |missed-optimization
Last reconfirmed|0000-00-00 00:00:00 |2006-02-06 15:00:36
date| |
Summary|Regression vs |Trivial operation not
|4.1.0cvs20051015 - Trivial |vectorized on char
|operation not vectorized |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26128
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug tree-optimization/26128] Trivial operation not vectorized on char
2006-02-06 14:55 [Bug regression/26128] New: Regression vs 4.1.0cvs20051015 - Trivial operation not vectorized hurbain at cri dot ensmp dot fr
2006-02-06 15:00 ` [Bug tree-optimization/26128] Trivial operation not vectorized on char pinskia at gcc dot gnu dot org
@ 2006-09-21 17:12 ` pinskia at gcc dot gnu dot org
2007-06-12 17:37 ` [Bug tree-optimization/26128] Trivial operation not vectorized on char/short pinskia at gcc dot gnu dot org
2009-02-06 1:45 ` pinskia at gcc dot gnu dot org
3 siblings, 0 replies; 5+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2006-09-21 17:12 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from pinskia at gcc dot gnu dot org 2006-09-21 17:11 -------
*** Bug 29170 has been marked as a duplicate of this bug. ***
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |eplondke at gmail dot com
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26128
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug tree-optimization/26128] Trivial operation not vectorized on char/short
2006-02-06 14:55 [Bug regression/26128] New: Regression vs 4.1.0cvs20051015 - Trivial operation not vectorized hurbain at cri dot ensmp dot fr
2006-02-06 15:00 ` [Bug tree-optimization/26128] Trivial operation not vectorized on char pinskia at gcc dot gnu dot org
2006-09-21 17:12 ` pinskia at gcc dot gnu dot org
@ 2007-06-12 17:37 ` pinskia at gcc dot gnu dot org
2009-02-06 1:45 ` pinskia at gcc dot gnu dot org
3 siblings, 0 replies; 5+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2007-06-12 17:37 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from pinskia at gcc dot gnu dot org 2007-06-12 17:36 -------
*** Bug 32309 has been marked as a duplicate of this bug. ***
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |gangren at google dot com
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26128
^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug tree-optimization/26128] Trivial operation not vectorized on char/short
2006-02-06 14:55 [Bug regression/26128] New: Regression vs 4.1.0cvs20051015 - Trivial operation not vectorized hurbain at cri dot ensmp dot fr
` (2 preceding siblings ...)
2007-06-12 17:37 ` [Bug tree-optimization/26128] Trivial operation not vectorized on char/short pinskia at gcc dot gnu dot org
@ 2009-02-06 1:45 ` pinskia at gcc dot gnu dot org
3 siblings, 0 replies; 5+ messages in thread
From: pinskia at gcc dot gnu dot org @ 2009-02-06 1:45 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from pinskia at gcc dot gnu dot org 2009-02-06 01:45 -------
*** Bug 39068 has been marked as a duplicate of this bug. ***
--
pinskia at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |dann at godzilla dot ics dot
| |uci dot edu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26128
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2009-02-06 1:45 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
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2006-02-06 14:55 [Bug regression/26128] New: Regression vs 4.1.0cvs20051015 - Trivial operation not vectorized hurbain at cri dot ensmp dot fr
2006-02-06 15:00 ` [Bug tree-optimization/26128] Trivial operation not vectorized on char pinskia at gcc dot gnu dot org
2006-09-21 17:12 ` pinskia at gcc dot gnu dot org
2007-06-12 17:37 ` [Bug tree-optimization/26128] Trivial operation not vectorized on char/short pinskia at gcc dot gnu dot org
2009-02-06 1:45 ` pinskia at gcc dot gnu dot org
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