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* [Bug middle-end/34971] New: bitfield rotates are folded and expanded wrong
@ 2008-01-25 15:25 rguenth at gcc dot gnu dot org
2008-01-25 15:34 ` [Bug middle-end/34971] " rguenth at gcc dot gnu dot org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2008-01-25 15:25 UTC (permalink / raw)
To: gcc-bugs
struct foo
{
unsigned long long b:40;
} x;
extern void abort (void);
void test1(unsigned long long res)
{
/* Build a rotate expression on a 40 bit argument. */
if ((x.b<<8) + (x.b>>32) != res)
abort ();
}
int main()
{
x.b = 0x0100000001;
test1(0x0000000101);
x.b = 0x0100000000;
test1(0x0000000001);
return 0;
}
Patch to fix the most obvious problems:
http://gcc.gnu.org/ml/gcc-patches/2008-01/msg01224.html
the (maybe better) alternative is to not allow ROTATE_EXPRs that
operate on entities whose precision doesn't match their modes bitsize.
--
Summary: bitfield rotates are folded and expanded wrong
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Keywords: wrong-code
Severity: normal
Priority: P3
Component: middle-end
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: rguenth at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34971
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/34971] bitfield rotates are folded and expanded wrong
2008-01-25 15:25 [Bug middle-end/34971] New: bitfield rotates are folded and expanded wrong rguenth at gcc dot gnu dot org
@ 2008-01-25 15:34 ` rguenth at gcc dot gnu dot org
2008-02-27 9:51 ` rguenth at gcc dot gnu dot org
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2008-01-25 15:34 UTC (permalink / raw)
To: gcc-bugs
------- Comment #1 from rguenth at gcc dot gnu dot org 2008-01-25 14:21 -------
Mine.
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
AssignedTo|unassigned at gcc dot gnu |rguenth at gcc dot gnu dot
|dot org |org
Status|UNCONFIRMED |ASSIGNED
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2008-01-25 14:21:13
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34971
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/34971] bitfield rotates are folded and expanded wrong
2008-01-25 15:25 [Bug middle-end/34971] New: bitfield rotates are folded and expanded wrong rguenth at gcc dot gnu dot org
2008-01-25 15:34 ` [Bug middle-end/34971] " rguenth at gcc dot gnu dot org
2008-02-27 9:51 ` rguenth at gcc dot gnu dot org
@ 2008-02-27 9:51 ` rguenth at gcc dot gnu dot org
2008-02-27 14:14 ` rguenth at gcc dot gnu dot org
2008-02-27 14:15 ` rguenth at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2008-02-27 9:51 UTC (permalink / raw)
To: gcc-bugs
------- Comment #3 from rguenth at gcc dot gnu dot org 2008-02-27 09:50 -------
Subject: Bug 34971
Author: rguenth
Date: Wed Feb 27 09:50:04 2008
New Revision: 132706
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=132706
Log:
2008-02-27 Richard Guenther <rguenther@suse.de>
PR middle-end/34971
* expr.c (expand_expr_real_1): Assert on rotates that operate
on partial modes.
* fold-const.c (fold_binary): Use the types precision, not the
bitsize of the mode if folding rotate expressions. Build rotates
only for full modes.
* gcc.c-torture/execute/pr34971.c: New testcase.
Added:
trunk/gcc/testsuite/gcc.c-torture/execute/pr34971.c
Modified:
trunk/gcc/ChangeLog
trunk/gcc/expr.c
trunk/gcc/fold-const.c
trunk/gcc/testsuite/ChangeLog
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34971
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/34971] bitfield rotates are folded and expanded wrong
2008-01-25 15:25 [Bug middle-end/34971] New: bitfield rotates are folded and expanded wrong rguenth at gcc dot gnu dot org
2008-01-25 15:34 ` [Bug middle-end/34971] " rguenth at gcc dot gnu dot org
@ 2008-02-27 9:51 ` rguenth at gcc dot gnu dot org
2008-02-27 9:51 ` rguenth at gcc dot gnu dot org
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2008-02-27 9:51 UTC (permalink / raw)
To: gcc-bugs
------- Comment #2 from rguenth at gcc dot gnu dot org 2008-02-27 09:50 -------
I'll apply this for 4.3.1 as well.
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Known to work| |4.4.0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34971
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/34971] bitfield rotates are folded and expanded wrong
2008-01-25 15:25 [Bug middle-end/34971] New: bitfield rotates are folded and expanded wrong rguenth at gcc dot gnu dot org
` (2 preceding siblings ...)
2008-02-27 9:51 ` rguenth at gcc dot gnu dot org
@ 2008-02-27 14:14 ` rguenth at gcc dot gnu dot org
2008-02-27 14:15 ` rguenth at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2008-02-27 14:14 UTC (permalink / raw)
To: gcc-bugs
------- Comment #4 from rguenth at gcc dot gnu dot org 2008-02-27 14:13 -------
Subject: Bug 34971
Author: rguenth
Date: Wed Feb 27 14:12:33 2008
New Revision: 132712
URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=132712
Log:
2008-02-27 Richard Guenther <rguenther@suse.de>
PR middle-end/35390
* fold-const.c (fold_unary): Return the correct argument,
converted to the result type.
* gcc.c-torture/execute/pr35390.c: New testcase.
PR middle-end/34971
* fold-const.c (fold_binary): Use the types precision, not the
bitsize of the mode if folding rotate expressions. Build rotates
only for full modes.
* gcc.c-torture/execute/pr34971.c: New testcase.
Added:
branches/gcc-4_3-branch/gcc/testsuite/gcc.c-torture/execute/pr34971.c
branches/gcc-4_3-branch/gcc/testsuite/gcc.c-torture/execute/pr35390.c
Modified:
branches/gcc-4_3-branch/gcc/ChangeLog
branches/gcc-4_3-branch/gcc/fold-const.c
branches/gcc-4_3-branch/gcc/testsuite/ChangeLog
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34971
^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/34971] bitfield rotates are folded and expanded wrong
2008-01-25 15:25 [Bug middle-end/34971] New: bitfield rotates are folded and expanded wrong rguenth at gcc dot gnu dot org
` (3 preceding siblings ...)
2008-02-27 14:14 ` rguenth at gcc dot gnu dot org
@ 2008-02-27 14:15 ` rguenth at gcc dot gnu dot org
4 siblings, 0 replies; 6+ messages in thread
From: rguenth at gcc dot gnu dot org @ 2008-02-27 14:15 UTC (permalink / raw)
To: gcc-bugs
------- Comment #5 from rguenth at gcc dot gnu dot org 2008-02-27 14:14 -------
Fixed for 4.3.0.
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|ASSIGNED |RESOLVED
Known to work|4.4.0 |4.3.0 4.4.0
Resolution| |FIXED
Target Milestone|--- |4.3.0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34971
^ permalink raw reply [flat|nested] 6+ messages in thread
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Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2008-01-25 15:25 [Bug middle-end/34971] New: bitfield rotates are folded and expanded wrong rguenth at gcc dot gnu dot org
2008-01-25 15:34 ` [Bug middle-end/34971] " rguenth at gcc dot gnu dot org
2008-02-27 9:51 ` rguenth at gcc dot gnu dot org
2008-02-27 9:51 ` rguenth at gcc dot gnu dot org
2008-02-27 14:14 ` rguenth at gcc dot gnu dot org
2008-02-27 14:15 ` rguenth at gcc dot gnu dot org
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