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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/59615] "asm goto" output or at least clobbered operands
Date: Sat, 28 Dec 2013 08:42:00 -0000 [thread overview]
Message-ID: <bug-59615-4-WVy1LlJi5w@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-59615-4@http.gcc.gnu.org/bugzilla/>
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59615
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jakub at gcc dot gnu.org
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
The reason for the limitation is that any needed reload out can't be then
inserted after the asm goto, but all the other edges would need to be split and
the reload outs inserted on all the edges.
Looking at your example though, can you explain why you want to use asm goto
then? I'd say that for addition, two conditional jumps and one comparison you
definitely don't want to use asm goto, the compiler can't see through it thus
can't optimize it. Why isn't what GCC generates sufficient? Do you have a
testcase?
next prev parent reply other threads:[~2013-12-28 8:42 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-28 0:23 [Bug c/59615] New: " hpa at zytor dot com
2013-12-28 8:42 ` jakub at gcc dot gnu.org [this message]
2013-12-28 10:29 ` [Bug c/59615] " ubizjak at gmail dot com
2013-12-28 16:28 ` jakub at gcc dot gnu.org
2013-12-30 1:37 ` hpa at zytor dot com
2013-12-30 17:53 ` glisse at gcc dot gnu.org
2013-12-30 17:56 ` jakub at gcc dot gnu.org
2013-12-30 18:17 ` glisse at gcc dot gnu.org
2021-09-01 1:05 ` [Bug inline-asm/59615] " pinskia at gcc dot gnu.org
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