* [Bug tree-optimization/106513] bswap is incorrectly generated
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
@ 2022-08-03 12:12 ` schwab@linux-m68k.org
2022-08-03 12:41 ` kristerw at gcc dot gnu.org
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From: schwab@linux-m68k.org @ 2022-08-03 12:12 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
--- Comment #1 from Andreas Schwab <schwab@linux-m68k.org> ---
This subexpression has undefined behaviour: (((int64_t) 0xff) << 56).
^ permalink raw reply [flat|nested] 11+ messages in thread
* [Bug tree-optimization/106513] bswap is incorrectly generated
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
2022-08-03 12:12 ` [Bug tree-optimization/106513] " schwab@linux-m68k.org
@ 2022-08-03 12:41 ` kristerw at gcc dot gnu.org
2022-08-05 22:15 ` [Bug tree-optimization/106513] [10/11/12/13 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit pinskia at gcc dot gnu.org
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From: kristerw at gcc dot gnu.org @ 2022-08-03 12:41 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
--- Comment #2 from Krister Walfridsson <kristerw at gcc dot gnu.org> ---
(In reply to Andreas Schwab from comment #1)
> This subexpression has undefined behaviour: (((int64_t) 0xff) << 56).
I thought that was allowed in GCC as the manual says
(https://gcc.gnu.org/onlinedocs/gcc-12.1.0/gcc/Integers-implementation.html#Integers-implementation)
"As an extension to the C language, GCC does not use the latitude given in C99
and C11 only to treat certain aspects of signed ‘<<’ as undefined."
If not, what behavior does the manual refer to?
^ permalink raw reply [flat|nested] 11+ messages in thread
* [Bug tree-optimization/106513] [10/11/12/13 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
2022-08-03 12:12 ` [Bug tree-optimization/106513] " schwab@linux-m68k.org
2022-08-03 12:41 ` kristerw at gcc dot gnu.org
@ 2022-08-05 22:15 ` pinskia at gcc dot gnu.org
2022-08-10 13:43 ` rguenth at gcc dot gnu.org
` (6 subsequent siblings)
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From: pinskia at gcc dot gnu.org @ 2022-08-05 22:15 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Known to fail| |4.5.3, 4.6.4
Summary|bswap is incorrectly |[10/11/12/13 Regression]
|generated |bswap pass misses that >>56
| |for signed types can be
| |replicate the sign bit
Known to work| |4.4.7
Target Milestone|--- |10.5
Status|UNCONFIRMED |NEW
Last reconfirmed| |2022-08-05
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed.
Better testcase (without the questionable undefined behavior):
typedef long long int int64_t;
__attribute__((noinline)) int64_t
swap64 (int64_t n)
{
return (((n & (((int64_t) 0xff) )) << 56) |
((n & (((int64_t) 0xff) << 8)) << 40) |
((n & (((int64_t) 0xff) << 16)) << 24) |
((n & (((int64_t) 0xff) << 24)) << 8) |
((n & (((int64_t) 0xff) << 32)) >> 8) |
((n & (((int64_t) 0xff) << 40)) >> 24) |
((n & (((int64_t) 0xff) << 48)) >> 40) |
((n & ((int64_t)(0xffull << 56))) >> 56));
}
int main (void)
{
volatile int64_t n = 0x8000000000000000l;
if (swap64(n) != 0xffffffffffffff80l)
__builtin_abort ();
return 0;
}
^ permalink raw reply [flat|nested] 11+ messages in thread
* [Bug tree-optimization/106513] [10/11/12/13 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
` (2 preceding siblings ...)
2022-08-05 22:15 ` [Bug tree-optimization/106513] [10/11/12/13 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit pinskia at gcc dot gnu.org
@ 2022-08-10 13:43 ` rguenth at gcc dot gnu.org
2022-08-10 13:51 ` rguenth at gcc dot gnu.org
` (5 subsequent siblings)
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From: rguenth at gcc dot gnu.org @ 2022-08-10 13:43 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |ASSIGNED
--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> ---
Mine.
diff --git a/gcc/gimple-ssa-store-merging.cc b/gcc/gimple-ssa-store-merging.cc
index 0640168bcc4..b80b8eac444 100644
--- a/gcc/gimple-ssa-store-merging.cc
+++ b/gcc/gimple-ssa-store-merging.cc
@@ -263,7 +263,7 @@ do_shift_rotate (enum tree_code code,
int count)
{
int i, size = TYPE_PRECISION (n->type) / BITS_PER_UNIT;
- unsigned head_marker;
+ uint64_t head_marker;
if (count < 0
|| count >= TYPE_PRECISION (n->type)
^ permalink raw reply [flat|nested] 11+ messages in thread
* [Bug tree-optimization/106513] [10/11/12/13 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
` (3 preceding siblings ...)
2022-08-10 13:43 ` rguenth at gcc dot gnu.org
@ 2022-08-10 13:51 ` rguenth at gcc dot gnu.org
2022-08-10 14:39 ` cvs-commit at gcc dot gnu.org
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From: rguenth at gcc dot gnu.org @ 2022-08-10 13:51 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Priority|P3 |P2
Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot gnu.org
^ permalink raw reply [flat|nested] 11+ messages in thread
* [Bug tree-optimization/106513] [10/11/12/13 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
` (4 preceding siblings ...)
2022-08-10 13:51 ` rguenth at gcc dot gnu.org
@ 2022-08-10 14:39 ` cvs-commit at gcc dot gnu.org
2022-08-10 14:40 ` cvs-commit at gcc dot gnu.org
` (3 subsequent siblings)
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From: cvs-commit at gcc dot gnu.org @ 2022-08-10 14:39 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:
https://gcc.gnu.org/g:f675afa4eeac9910a2c085a95aa04d6d9f2fd8d6
commit r13-2013-gf675afa4eeac9910a2c085a95aa04d6d9f2fd8d6
Author: Richard Biener <rguenther@suse.de>
Date: Wed Aug 10 15:45:22 2022 +0200
tree-optimization/106513 - fix mistake in bswap symbolic number shifts
This fixes a mistake in typing a local variable in the symbolic
shift routine.
PR tree-optimization/106513
* gimple-ssa-store-merging.cc (do_shift_rotate): Use uint64_t
for head_marker.
* gcc.dg/torture/pr106513.c: New testcase.
^ permalink raw reply [flat|nested] 11+ messages in thread
* [Bug tree-optimization/106513] [10/11/12/13 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
` (5 preceding siblings ...)
2022-08-10 14:39 ` cvs-commit at gcc dot gnu.org
@ 2022-08-10 14:40 ` cvs-commit at gcc dot gnu.org
2022-10-11 13:04 ` [Bug tree-optimization/106513] [10/11 " cvs-commit at gcc dot gnu.org
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From: cvs-commit at gcc dot gnu.org @ 2022-08-10 14:40 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Richard Biener
<rguenth@gcc.gnu.org>:
https://gcc.gnu.org/g:ab2ca2dbd528f0564b80fa0e6eda96e0237742bc
commit r12-8677-gab2ca2dbd528f0564b80fa0e6eda96e0237742bc
Author: Richard Biener <rguenther@suse.de>
Date: Wed Aug 10 15:45:22 2022 +0200
tree-optimization/106513 - fix mistake in bswap symbolic number shifts
This fixes a mistake in typing a local variable in the symbolic
shift routine.
PR tree-optimization/106513
* gimple-ssa-store-merging.cc (do_shift_rotate): Use uint64_t
for head_marker.
* gcc.dg/torture/pr106513.c: New testcase.
(cherry picked from commit f675afa4eeac9910a2c085a95aa04d6d9f2fd8d6)
^ permalink raw reply [flat|nested] 11+ messages in thread
* [Bug tree-optimization/106513] [10/11 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
` (6 preceding siblings ...)
2022-08-10 14:40 ` cvs-commit at gcc dot gnu.org
@ 2022-10-11 13:04 ` cvs-commit at gcc dot gnu.org
2022-10-14 10:47 ` [Bug tree-optimization/106513] [10 " cvs-commit at gcc dot gnu.org
2022-10-14 10:48 ` rguenth at gcc dot gnu.org
9 siblings, 0 replies; 11+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2022-10-11 13:04 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Richard Biener
<rguenth@gcc.gnu.org>:
https://gcc.gnu.org/g:ec718fb7a3a58955017cd80f6a8927afbe340fc4
commit r11-10306-gec718fb7a3a58955017cd80f6a8927afbe340fc4
Author: Richard Biener <rguenther@suse.de>
Date: Wed Aug 10 15:45:22 2022 +0200
tree-optimization/106513 - fix mistake in bswap symbolic number shifts
This fixes a mistake in typing a local variable in the symbolic
shift routine.
PR tree-optimization/106513
* gimple-ssa-store-merging.c (do_shift_rotate): Use uint64_t
for head_marker.
* gcc.dg/torture/pr106513.c: New testcase.
(cherry picked from commit f675afa4eeac9910a2c085a95aa04d6d9f2fd8d6)
^ permalink raw reply [flat|nested] 11+ messages in thread
* [Bug tree-optimization/106513] [10 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
` (7 preceding siblings ...)
2022-10-11 13:04 ` [Bug tree-optimization/106513] [10/11 " cvs-commit at gcc dot gnu.org
@ 2022-10-14 10:47 ` cvs-commit at gcc dot gnu.org
2022-10-14 10:48 ` rguenth at gcc dot gnu.org
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From: cvs-commit at gcc dot gnu.org @ 2022-10-14 10:47 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
--- Comment #8 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-10 branch has been updated by Richard Biener
<rguenth@gcc.gnu.org>:
https://gcc.gnu.org/g:29ad829c93d530e75dee88d2550350c14fcaf8f6
commit r10-11038-g29ad829c93d530e75dee88d2550350c14fcaf8f6
Author: Richard Biener <rguenther@suse.de>
Date: Wed Aug 10 15:45:22 2022 +0200
tree-optimization/106513 - fix mistake in bswap symbolic number shifts
This fixes a mistake in typing a local variable in the symbolic
shift routine.
PR tree-optimization/106513
* gimple-ssa-store-merging.c (do_shift_rotate): Use uint64_t
for head_marker.
* gcc.dg/torture/pr106513.c: New testcase.
(cherry picked from commit f675afa4eeac9910a2c085a95aa04d6d9f2fd8d6)
^ permalink raw reply [flat|nested] 11+ messages in thread
* [Bug tree-optimization/106513] [10 Regression] bswap pass misses that >>56 for signed types can be replicate the sign bit
2022-08-03 11:56 [Bug tree-optimization/106513] New: bswap is incorrectly generated kristerw at gcc dot gnu.org
` (8 preceding siblings ...)
2022-10-14 10:47 ` [Bug tree-optimization/106513] [10 " cvs-commit at gcc dot gnu.org
@ 2022-10-14 10:48 ` rguenth at gcc dot gnu.org
9 siblings, 0 replies; 11+ messages in thread
From: rguenth at gcc dot gnu.org @ 2022-10-14 10:48 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106513
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Known to work| |10.4.1
Resolution|--- |FIXED
Known to fail| |10.4.0
Status|ASSIGNED |RESOLVED
--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
Fixed.
^ permalink raw reply [flat|nested] 11+ messages in thread