From: Richard Biener <richard.guenther@gmail.com>
To: Aldy Hernandez <aldyh@redhat.com>
Cc: Andrew MacLeod <amacleod@redhat.com>,
gcc-patches <gcc-patches@gcc.gnu.org>
Subject: Re: Avoid generating useless range info
Date: Fri, 16 Jun 2017 08:00:00 -0000 [thread overview]
Message-ID: <CAFiYyc1S5-vVEOMGPQ61E2j9Fh37r8z+emNnDwrHXoY0m_G04g@mail.gmail.com> (raw)
In-Reply-To: <85de74ae-9680-1461-a289-42c915b5285a@redhat.com>
On Wed, Jun 14, 2017 at 6:41 PM, Aldy Hernandez <aldyh@redhat.com> wrote:
> Hi!
>
> As discovered in my range class work, we seem to generate a significant
> amount of useless range info out of VRP.
>
> Is there any reason why we can't avoid generating any range info that spans
> the entire domain, and yet contains nothing in the non-zero bitmask?
>
> The attached patch passes bootstrap, and the one regression it causes is
> because now the -Walloca-larger-than= pass is better able to determine that
> there is no range information at all, and the testcase is unbounded.
> So...win, win.
>
> OK for trunk?
Can you please do this in set_range_info itself? Thus, if min ==
wi::min_value && max == wi::max_value
simply return? (do not use TYPE_MIN?MAX_VALUE please)
Thanks,
Richard.
> Aldy
next prev parent reply other threads:[~2017-06-16 8:00 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-06-14 16:41 Aldy Hernandez
2017-06-16 8:00 ` Richard Biener [this message]
2017-06-23 9:02 ` Aldy Hernandez
[not found] ` <CAGm3qMXOYa3Km6FGiji0j2txeZJfyiLTR7V6EDMTDEDQo0RWBA@mail.gmail.com>
2017-06-23 10:24 ` Richard Biener
2017-06-23 10:32 ` Jakub Jelinek
2017-06-23 11:01 ` Richard Biener
2017-06-27 10:26 ` Aldy Hernandez
2017-06-27 10:38 ` Jakub Jelinek
2017-06-28 7:56 ` Aldy Hernandez
2017-06-29 9:53 ` Richard Biener
2017-08-02 13:29 ` [testsuite, committed] Use relative line number in gcc.dg/Walloca-14.c Tom de Vries
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=CAFiYyc1S5-vVEOMGPQ61E2j9Fh37r8z+emNnDwrHXoY0m_G04g@mail.gmail.com \
--to=richard.guenther@gmail.com \
--cc=aldyh@redhat.com \
--cc=amacleod@redhat.com \
--cc=gcc-patches@gcc.gnu.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).