From: Andrew Burgess <andrew.burgess@embecosm.com>
To: Stafford Horne <shorne@gmail.com>
Cc: GDB patches <gdb-patches@sourceware.org>,
GNU Binutils <binutils@sourceware.org>,
Andrey Bacherov <bandvig@mail.ru>,
Openrisc <openrisc@lists.librecores.org>
Subject: Re: [PATCH v2 6/6] sim/common: Fix issue with wrong byte order on BE targets
Date: Sat, 13 Apr 2019 21:30:00 -0000 [thread overview]
Message-ID: <20190413213027.GH2737@embecosm.com> (raw)
In-Reply-To: <20190412202145.GA32284@lianli.shorne-pla.net>
* Stafford Horne <shorne@gmail.com> [2019-04-13 05:21:45 +0900]:
> Hi Andrew,
>
> On Thu, Apr 11, 2019 at 11:27:49PM +0100, Andrew Burgess wrote:
> > * Stafford Horne <shorne@gmail.com> [2019-04-10 06:39:25 +0900]:
> >
> > > Currently only the OpenRISC sim uses this JOINSIDF() function to compose a
> > > double float from 2 registers. The old code doesn't seem to work as the
> > > work order gets swapped when running on a x86_64 host. This change
> > > fixes that, but I am not sure if its the best thing to do.
> > >
> > > On mips they do similar reg pair floating point operations composing
> > > doubles from 2 32-bit registers in sim/mips/cp1.c value_fpr().
> > >
> > > sim/common/ChangeLog:
> > >
> > > * cgen-ops.h (JOINSIDF): Fix big endian check.
> > > ---
> > > sim/common/cgen-ops.h | 8 ++------
> > > 1 file changed, 2 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/sim/common/cgen-ops.h b/sim/common/cgen-ops.h
> > > index 841552066f..d718394723 100644
> > > --- a/sim/common/cgen-ops.h
> > > +++ b/sim/common/cgen-ops.h
> > > @@ -431,12 +431,8 @@ JOINSIDI (SI x0, SI x1)
> > > SEMOPS_INLINE DF
> > > JOINSIDF (SI x0, SI x1)
> > > {
> > > - union { SI in[2]; DF out; } x;
> > > - if (CURRENT_TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
> >
> > I think this is the problem with the existing code, we're using memory
> > on the HOST to perform packing / unpacking, and so its the byte
> > ordering of the HOST that we care about here, not the target.
> >
> > If I change the above line to instead be:
> >
> > if (HOST_BYTE_ORDER == BFD_ENDIAN_BIG)
> >
> > then everything works fine.
> >
> > On inspection I believe all of the uses of CURRENT_TARGET_BYTE_ORDER
> > in this file should be similarly replaced.
> >
> > I've attached a patch for this change. If you agree I'll go ahead and
> > push it.
>
> I tested this with the or1k testsuite and it does seem to work fine, thank you.
> Please go ahead.
>
> I thought I had tried this fix as well, I guess not.
Thanks for testing this.
I've pushed this patch now.
Andrew
prev parent reply other threads:[~2019-04-13 21:30 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-09 21:39 [PATCH v2 0/6] OpenRISC orfpx64a32 support Stafford Horne
2019-04-09 21:39 ` [PATCH v2 1/6] cpu: Add support for orfp64a32 spec Stafford Horne
2019-04-09 21:39 ` [PATCH v2 4/6] sim/common: Wire in df/di conversion Stafford Horne
2019-04-13 21:59 ` Andrew Burgess
2019-04-09 21:40 ` [PATCH v2 3/6] sim/or1k: Regenerate sim for orfp64a32 spec Stafford Horne
2019-04-13 21:40 ` Andrew Burgess
2019-04-14 6:44 ` Stafford Horne
2019-04-09 21:40 ` [PATCH v2 5/6] sim/or1k: Add test for 64-bit fpu operations Stafford Horne
2019-04-13 21:36 ` Andrew Burgess
2019-04-09 21:40 ` [PATCH v2 2/6] opcodes: Regenerate opcodes for orfp64a32 spec Stafford Horne
2019-04-11 8:45 ` Nick Clifton
2019-04-09 21:40 ` [PATCH v2 6/6] sim/common: Fix issue with wrong byte order on BE targets Stafford Horne
2019-04-11 22:27 ` Andrew Burgess
2019-04-12 20:21 ` Stafford Horne
2019-04-13 21:30 ` Andrew Burgess [this message]
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=20190413213027.GH2737@embecosm.com \
--to=andrew.burgess@embecosm.com \
--cc=bandvig@mail.ru \
--cc=binutils@sourceware.org \
--cc=gdb-patches@sourceware.org \
--cc=openrisc@lists.librecores.org \
--cc=shorne@gmail.com \
/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).