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From: "petro.karashchenko at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/94387] Excess read instructions are generated in case of writing to fields of volatile + packed type (structure)
Date: Mon, 30 Mar 2020 08:44:07 +0000	[thread overview]
Message-ID: <bug-94387-4-1f8jsLRneW@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-94387-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94387

--- Comment #6 from Petro Karashchenko <petro.karashchenko at gmail dot com> ---
Richard Biener thank you for suggestion, but __attribute__((aligned(..))) is
applied only to the base address of the struct, hence to the first field only,
so if I'm having other fields tightly packed and there are 16, 32 or 64 bit
types I will still get excess read instructions generated. In my case I'm
having uint8_t *p0, uint8_t *p1 as an inputs and can't rely that those pointers
are aligned to 16, 32 or 64, but are byte aligned.

  parent reply	other threads:[~2020-03-30  8:44 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-29 14:23 [Bug middle-end/94387] New: " petro.karashchenko at gmail dot com
2020-03-29 14:28 ` [Bug middle-end/94387] " petro.karashchenko at gmail dot com
2020-03-29 22:41 ` pinskia at gcc dot gnu.org
2020-03-29 22:43 ` pinskia at gcc dot gnu.org
2020-03-30  5:44 ` petro.karashchenko at gmail dot com
2020-03-30  8:17 ` rguenth at gcc dot gnu.org
2020-03-30  8:44 ` petro.karashchenko at gmail dot com [this message]
2020-04-19 20:16 ` petro.karashchenko at gmail dot com

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