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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/109484] [Wrong Code][inline-asm] output operands overlap with output
Date: Wed, 12 Apr 2023 13:03:40 +0000	[thread overview]
Message-ID: <bug-109484-4-qL7NzDYf1D@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-109484-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109484

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |INVALID
             Status|UNCONFIRMED                 |RESOLVED
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Similar bug.  The basic GCC expectations for inline-asm is that the whole
assembly template after substitutions (which is for GCC mostly intentionally a
black box) works as a single instruction which reads all its inputs (and that
obviously doesn't mean just  the input themselves, but also any other
register/memory used in the input) and then stores all its outputs.
Early clobbers are the way to tell the compiler that it is not the case and
some output is written before all the inputs are used.

  parent reply	other threads:[~2023-04-12 13:03 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-04-12  9:49 [Bug middle-end/109484] New: " 570070308 at qq dot com
2023-04-12 10:51 ` [Bug middle-end/109484] " rguenth at gcc dot gnu.org
2023-04-12 11:03 ` 570070308 at qq dot com
2023-04-12 11:07 ` rguenth at gcc dot gnu.org
2023-04-12 11:09 ` rguenth at gcc dot gnu.org
2023-04-12 11:13 ` 570070308 at qq dot com
2023-04-12 12:48 ` 570070308 at qq dot com
2023-04-12 13:03 ` jakub at gcc dot gnu.org [this message]
2023-04-13 11:51 ` xry111 at gcc dot gnu.org
2023-04-13 11:55 ` jakub at gcc dot gnu.org

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