From: Paul Koning <paulkoning@comcast.net>
To: Andreas Schwab <schwab@linux-m68k.org>
Cc: GCC Development <gcc@gcc.gnu.org>
Subject: Re: Signed vs. unsigned compares
Date: Fri, 17 Jun 2022 12:52:10 -0400 [thread overview]
Message-ID: <AA5910BA-7A9E-4F35-8C04-A6A6EDDBF5A7@comcast.net> (raw)
In-Reply-To: <8735g3s2yw.fsf@igel.home>
> On Jun 17, 2022, at 11:51 AM, Andreas Schwab <schwab@linux-m68k.org> wrote:
>
> On Jun 17 2022, Paul Koning via Gcc wrote:
>
>> In expanding a longer-than-word compare, I need to do things differently depending on whether a signed vs. unsigned compare is needed. But it seems the compare operation applies to either. How can I do this in the target code?
>
> There are both signed and unsigned comparison operations, eg. GE
> vs. GEU.
>
> --
> Andreas Schwab, schwab@linux-m68k.org
It looks like what I need is to define additional CCmodes, to describe "cc mode valid for unsigned comparison" vs. "cc mode valid for signed comparison". Right now I don't make that distinction and that reportedly can produce bad code errors.
paul
prev parent reply other threads:[~2022-06-17 16:52 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-17 15:32 Paul Koning
2022-06-17 15:51 ` Andreas Schwab
2022-06-17 16:52 ` Paul Koning [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=AA5910BA-7A9E-4F35-8C04-A6A6EDDBF5A7@comcast.net \
--to=paulkoning@comcast.net \
--cc=gcc@gcc.gnu.org \
--cc=schwab@linux-m68k.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).