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* [Bug target/55218] New: armv6 doesn't use unaligned access for packed structures
@ 2012-11-05 22:00 michael.hope at linaro dot org
2012-11-05 22:04 ` [Bug target/55218] " michael.hope at linaro dot org
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: michael.hope at linaro dot org @ 2012-11-05 22:00 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55218
Bug #: 55218
Summary: armv6 doesn't use unaligned access for packed
structures
Classification: Unclassified
Product: gcc
Version: 4.7.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
AssignedTo: unassigned@gcc.gnu.org
ReportedBy: michael.hope@linaro.org
Created attachment 28622
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28622
Test case
The GCC ARM target uses the armv6 and above unaligned loads for packed
structures and block copies. This works correctly for -march=armv7-a and
-march=armv6t2, but generates the old byte-by-byte field access for
-march=armv6.
The block copy is fine. readelf -A shows that the compiler intended to use
unaligned access. I'm suspicious that GCC is using the extv pattern to extract
the field, and this pattern is only available on cores with Thumb-2 support.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug target/55218] armv6 doesn't use unaligned access for packed structures
2012-11-05 22:00 [Bug target/55218] New: armv6 doesn't use unaligned access for packed structures michael.hope at linaro dot org
@ 2012-11-05 22:04 ` michael.hope at linaro dot org
2012-11-07 2:13 ` hp at gcc dot gnu.org
2023-02-25 6:50 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: michael.hope at linaro dot org @ 2012-11-05 22:04 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55218
Michael Hope <michael.hope at linaro dot org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target| |arm
--- Comment #1 from Michael Hope <michael.hope at linaro dot org> 2012-11-05 22:04:03 UTC ---
See also:
http://lists.linaro.org/pipermail/linaro-toolchain/2012-November/002921.html
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug target/55218] armv6 doesn't use unaligned access for packed structures
2012-11-05 22:00 [Bug target/55218] New: armv6 doesn't use unaligned access for packed structures michael.hope at linaro dot org
2012-11-05 22:04 ` [Bug target/55218] " michael.hope at linaro dot org
@ 2012-11-07 2:13 ` hp at gcc dot gnu.org
2023-02-25 6:50 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: hp at gcc dot gnu.org @ 2012-11-07 2:13 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55218
--- Comment #2 from Hans-Peter Nilsson <hp at gcc dot gnu.org> 2012-11-07 02:13:32 UTC ---
(After reading the linked post.) Somewhat related: maybe the changes.html text
should say "bootloader" or "startup code" instead of kernel because everyone
just thinks it just means "Linux". Patches welcome.
^ permalink raw reply [flat|nested] 4+ messages in thread
* [Bug target/55218] armv6 doesn't use unaligned access for packed structures
2012-11-05 22:00 [Bug target/55218] New: armv6 doesn't use unaligned access for packed structures michael.hope at linaro dot org
2012-11-05 22:04 ` [Bug target/55218] " michael.hope at linaro dot org
2012-11-07 2:13 ` hp at gcc dot gnu.org
@ 2023-02-25 6:50 ` pinskia at gcc dot gnu.org
2 siblings, 0 replies; 4+ messages in thread
From: pinskia at gcc dot gnu.org @ 2023-02-25 6:50 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55218
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2023-02-25
Ever confirmed|0 |1
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed. very similar to PR 51709 if not the same.
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2023-02-25 6:50 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2012-11-05 22:00 [Bug target/55218] New: armv6 doesn't use unaligned access for packed structures michael.hope at linaro dot org
2012-11-05 22:04 ` [Bug target/55218] " michael.hope at linaro dot org
2012-11-07 2:13 ` hp at gcc dot gnu.org
2023-02-25 6:50 ` pinskia at gcc dot gnu.org
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