From: Blue Swirl <blauwirbel@gmail.com>
To: Paul Brook <paul@codesourcery.com>
Cc: qemu-devel@nongnu.org, Richard Henderson <rth@twiddle.net>
Subject: Re: [Qemu-devel] TCG: AREG0 removal planning
Date: Wed, 11 May 2011 20:35:47 +0300 [thread overview]
Message-ID: <BANLkTintbUwJAiWwzUkcinJ1a4ZS0JQ4sA@mail.gmail.com> (raw)
In-Reply-To: <201105102357.17637.paul@codesourcery.com>
On Wed, May 11, 2011 at 1:57 AM, Paul Brook <paul@codesourcery.com> wrote:
>> While we're at it, let us change things a bit further to allow guest
>> byte-swap load/store insns to be implemented more efficiently. For
>> instance, currently a sparc load_asr (little-endian), as emulated on
>> an x86 host, does the byte swap twice.
>
> FWIW this also ends up interacting with the device and bus models. This is
> partially implemented by the endian parameter of cpu_register_io_memory et.
> al. This may also be a runtime property, either part of the CPU state (e.g.
> ARM where instruction and data accesses may have different endianness), or
> even a per-page TLB attribute (PPC?).
SuperSparc (Sparc32) MMU had a bit for reversing the endianness of a
page, on Sparc64 there are many levels where this can be done (global
CPU mode flag, MMU page flag and some memory accesses can use byte
swapping ASIs). I don't think they are used though.
next prev parent reply other threads:[~2011-05-11 17:36 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-10 20:54 [Qemu-devel] TCG: AREG0 removal planning Blue Swirl
2011-05-10 21:28 ` Paul Brook
2011-05-11 17:25 ` Blue Swirl
2011-05-11 18:39 ` Lluís
2011-05-11 19:15 ` Blue Swirl
2011-05-12 15:02 ` Avi Kivity
2011-05-16 16:16 ` Paul Brook
2011-05-16 19:18 ` Blue Swirl
2011-05-10 21:31 ` Stefan Weil
2011-05-10 21:58 ` Richard Henderson
2011-05-10 22:57 ` Paul Brook
2011-05-11 17:35 ` Blue Swirl [this message]
2011-05-11 17:32 ` Blue Swirl
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=BANLkTintbUwJAiWwzUkcinJ1a4ZS0JQ4sA@mail.gmail.com \
--to=blauwirbel@gmail.com \
--cc=paul@codesourcery.com \
--cc=qemu-devel@nongnu.org \
--cc=rth@twiddle.net \
/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 NNTP newsgroup(s).