public inbox for
 help / color / mirror / Atom feed
From: Richard Biener <>
To: Segher Boessenkool <>
Cc: Hongyu Wang <>,,
Subject: Re: [PATCH] rs6000: Adjust loop_unroll_adjust to match middle-end change [PR 107692]
Date: Tue, 22 Nov 2022 10:00:28 +0100	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

On Fri, Nov 18, 2022 at 3:47 PM Segher Boessenkool
<> wrote:
> [ Please cc: me and Ke Wen on rs6000 patches ]
> On Thu, Nov 17, 2022 at 07:54:29AM +0800, Hongyu Wang wrote:
> > r13-3950-g071e428c24ee8c enables O2 small loop unrolling, but it breaks
> > -fno-unroll-loops for rs6000 with loop_unroll_adjust hook. Adjust the
> > option handling and target hook accordingly.
> NAK.
> This is wrong.  -munroll-only-small-loops does not enable loop
> unrolling; doing that with a machine flag is completely unmaintainable,
> also for people using different targets.

I suggested that because doing it fully in the backend by twiddling
-funroll-loops is unmaintainable as well.

> Something in your patch was wrong, please fix that (or revert the
> patch).  You should not have to touch config/rs6000/ at all.

Sure something is wrong, but I think there's the opportunity to
simplify rs6000/ and s390x/, the only other two implementors of
the hook used.


> Segher

  reply	other threads:[~2022-11-22  9:00 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-16 23:54 Hongyu Wang
2022-11-18 14:46 ` Segher Boessenkool
2022-11-22  9:00   ` Richard Biener [this message]
2022-11-23  1:53     ` Hongyu Wang
2022-11-23 20:02       ` Richard Biener

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:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='' \ \ \ \ \ \

* 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).