From: Andrew Haley <aph@redhat.com>
To: gcc-patches@gcc.gnu.org
Subject: Re: [PATCH] [AArch64] support -mfentry feature for arm64
Date: Mon, 18 Apr 2016 14:32:00 -0000 [thread overview]
Message-ID: <5714F001.8090408@redhat.com> (raw)
In-Reply-To: <alpine.LNX.2.20.1604152026570.26109@monopod.intra.ispras.ru>
On 04/15/2016 06:29 PM, Alexander Monakov wrote:
> Alternatively: replace first nop with a short forward branch that
> jumps over the rest of the pad, patch rest of the pad, patch the
> initial forward branch.
That may not be safe. Consider an implementation which looks ahead in
the instruction stream and decodes the instructions speculatively. I
suppse you could begin the block of instructions after the branch with
an ISB. On balance, the trap sounds like the best plan. We do this
in Java all the time: every method begins with a NOP, and we patch it
either to a trap or to a call to the replacement code.
Andrew.
next prev parent reply other threads:[~2016-04-18 14:32 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-14 8:13 Li Bin
2016-03-14 8:12 ` Li Bin
2016-04-14 13:08 ` Maxim Kuvyrkov
2016-04-14 13:15 ` Andrew Pinski
2016-04-14 15:58 ` Szabolcs Nagy
2016-04-18 13:26 ` Alexander Monakov
2016-04-18 13:34 ` Ramana Radhakrishnan
2016-04-18 13:44 ` Alexander Monakov
2016-04-18 13:57 ` Ramana Radhakrishnan
2016-04-18 14:03 ` Alexander Monakov
2016-04-18 14:31 ` Szabolcs Nagy
2016-04-18 15:54 ` Alexander Monakov
2016-04-19 6:46 ` AKASHI Takahiro
2016-04-19 6:13 ` AKASHI Takahiro
2016-04-19 6:44 ` Alexander Monakov
2016-04-20 0:33 ` AKASHI Takahiro
2016-04-20 10:02 ` Szabolcs Nagy
2016-04-15 15:40 ` Michael Matz
2016-04-15 17:29 ` Alexander Monakov
2016-04-17 15:06 ` Alexander Monakov
2016-04-18 12:12 ` Michael Matz
2016-04-19 6:26 ` AKASHI Takahiro
2016-04-19 6:39 ` Alexander Monakov
2016-04-20 1:23 ` AKASHI Takahiro
2016-04-20 16:45 ` Szabolcs Nagy
2016-04-19 16:03 ` Torsten Duwe
2016-04-18 14:32 ` Andrew Haley [this message]
2016-04-18 17:13 ` Michael Matz
2016-04-18 17:17 ` Andrew Haley
2016-04-18 17:34 ` Michael Matz
2016-04-19 8:00 ` Andrew Haley
2016-04-19 13:19 ` Michael Matz
2016-04-19 13:25 ` Andrew Haley
2016-04-19 14:38 ` Pedro Alves
2016-04-19 15:02 ` Andrew Haley
2016-04-19 6:08 ` AKASHI Takahiro
-- strict thread matches above, loose matches on Subject: below --
2015-10-22 13:24 Li Bin
2015-10-22 13:53 ` Marcus Shawcroft
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5714F001.8090408@redhat.com \
--to=aph@redhat.com \
--cc=gcc-patches@gcc.gnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).