From: Chris Lattner <sabre@nondot.org>
To: Zdenek Dvorak <rakdver@atrey.karlin.mff.cuni.cz>
Cc: Andrew MacLeod <amacleod@redhat.com>, Jeff Law <law@redhat.com>,
Diego Novillo <dnovillo@redhat.com>,
gcc mailing list <gcc@gcc.gnu.org>
Subject: Re: [tree-ssa] Lazy updating of stmt operands
Date: Mon, 15 Dec 2003 20:47:00 -0000 [thread overview]
Message-ID: <Pine.LNX.4.44.0312151410580.27073-100000@nondot.org> (raw)
Zdenek Dvorak wrote:
> suppose a statement is changed. To update the immediate uses of this
> statement, you would need to go to the defining statement for each
> variable, find yourself in a (possibly very long) list of uses and
> make the update. This would be a disaster for the performance.
This is exactly what I was talking about here:
http://gcc.gnu.org/ml/gcc/2003-12/msg00691.html
Imagine if the value you are using is the constant "0". If you represent
use chains of the 0, there may be "several" instructions on the list. The
lists can get large. In LLVM, this is a constant time operation.
-Chris
--
http://llvm.cs.uiuc.edu/
http://www.nondot.org/~sabre/Projects/
next reply other threads:[~2003-12-15 20:29 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-12-15 20:47 Chris Lattner [this message]
-- strict thread matches above, loose matches on Subject: below --
2003-12-11 22:31 Chris Lattner
2003-12-12 3:14 ` law
2003-12-12 3:58 ` Chris Lattner
2003-12-12 19:25 ` Andrew MacLeod
2003-12-12 19:42 ` Zdenek Dvorak
2003-12-12 19:45 ` Andrew MacLeod
2003-12-12 19:54 ` Chris Lattner
2003-12-12 19:55 ` Andrew MacLeod
2003-12-12 21:26 ` Diego Novillo
2003-12-12 19:57 ` Chris Lattner
2003-12-13 16:02 ` Andrew MacLeod
2003-12-14 3:39 ` Chris Lattner
2003-12-15 23:41 ` law
2003-12-16 6:02 ` Andrew MacLeod
2003-12-07 16:22 Zdenek Dvorak
2003-12-07 17:14 ` Diego Novillo
2003-12-07 17:28 ` Zdenek Dvorak
2003-12-07 17:36 ` Diego Novillo
2003-12-07 18:09 ` Zdenek Dvorak
2003-12-11 19:39 ` law
2003-12-07 22:20 ` Steven Bosscher
2003-12-09 14:30 ` Andrew MacLeod
2003-12-09 20:40 ` Zdenek Dvorak
2003-12-11 19:41 ` law
2003-12-11 19:38 ` law
2003-12-11 19:52 ` Zdenek Dvorak
2003-12-11 22:36 ` Zdenek Dvorak
2003-12-11 23:34 ` Andrew MacLeod
2003-12-15 19:10 ` Andrew MacLeod
2003-12-15 19:19 ` Zdenek Dvorak
2003-12-15 20:55 ` Andrew MacLeod
2003-12-15 21:06 ` Zdenek Dvorak
2003-12-15 21:39 ` Andrew MacLeod
2003-12-15 21:49 ` Zdenek Dvorak
2003-12-15 22:04 ` Andrew MacLeod
2003-12-15 22:39 ` law
2003-12-17 4:56 ` law
2003-12-16 23:32 ` Andrew MacLeod
2003-12-17 0:09 ` Zdenek Dvorak
2003-12-17 0:21 ` Andrew MacLeod
2003-12-17 3:28 ` law
2003-12-15 19:28 ` Diego Novillo
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=Pine.LNX.4.44.0312151410580.27073-100000@nondot.org \
--to=sabre@nondot.org \
--cc=amacleod@redhat.com \
--cc=dnovillo@redhat.com \
--cc=gcc@gcc.gnu.org \
--cc=law@redhat.com \
--cc=rakdver@atrey.karlin.mff.cuni.cz \
/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).