public inbox for
 help / color / mirror / Atom feed
From: Hongyu Wang <>
To: Richard Biener <>
Cc: Segher Boessenkool <>,
	Hongyu Wang <>,,
Subject: Re: [PATCH] rs6000: Adjust loop_unroll_adjust to match middle-end change [PR 107692]
Date: Wed, 23 Nov 2022 09:53:20 +0800	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

Hi, Segher and Richard

> > 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.

If I understand correctly, the wrong part is we should not break the
logic of -funroll-loops and check OPTION_SET_P in
targetm.loop_unroll_adjust to pretend the loop-unrolling is disabled
with -fno-unroll-loops.
I don't have a good idea to resolve this, perhaps add another hook and
check OPTION_SET_P (flag_unroll_loops) && munroll_only_small_loops
there and use that hook in rtl_loop_unroll::gate (), but still it
doesn't work if we want to strictly follow the logic that
-munroll-only-small-loops should not enable loop unrolling.
IMHO the middle-end part with target hook looks quite tricky (and of
course the OPTION_SET_P in the target hook). So Richard if you agree,
I'd like to install the reversion patch posted in
and move all them to the backend first.


Hongyu, Wang

  reply	other threads:[~2022-11-23  1:53 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
2022-11-23  1:53     ` Hongyu Wang [this message]
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).