From: David Malcolm <dmalcolm@redhat.com>
To: Arnaldo <arnaldo.cruz@upr.edu>
Cc: gcc@gcc.gnu.org
Subject: Re: Iterating over RTL in Graphite
Date: Fri, 17 Feb 2012 22:52:00 -0000 [thread overview]
Message-ID: <1329507251.15787.25.camel@surprise> (raw)
In-Reply-To: <CAB=90XDwy+H3q4BfMVOeVb7BRHHD=_Ju4iV-k6E7hsqaNWzxZg@mail.gmail.com>
On Thu, 2012-02-16 at 19:17 -0400, Arnaldo wrote:
> Hello everyone,
>
> I'm working on an extension to the Graphite pass of GCC 4.4.0. My
> intention is to associate costs to RTL instructions by adding them as
> RTX attributes to a machine description file, and to read them back
> during the Graphite pass by iterating through each basic block.
>
> Is the RTL available during this optimization pass? I'm not sure this
> is the case as I get a segfault when trying to iterate over the RTL
> with the code below ("internal compiler error: Segmentation fault"). I
> don't need the fully resolved RTL, just to be able to read the
> attribute given an RTL instruction.
>
> I've tried debugging the compiler with gdb but it can't find the
> debugging symbols even though they're there. I'll keep trying to get
> gdb to work but any leads on reading these attributes from within
> Graphite is greatly appreciated.
I don't know about GCC 4.4, but a while back I wrote a script using my
GCC Python plugin to draw a "subway map" of GCC 4.6's passes:
http://gcc.gnu.org/ml/gcc/2011-07/msg00157.html
which you can see here:
http://gcc-python-plugin.readthedocs.org/en/latest/tables-of-passes.html
If I reading things correctly, the graphite passes happen whilst the
code is still in gimple form: the blocks are converted to RTL form in
the "expand" pass, which happens about 20 or so passes later.
Caveat: I'm not familiar with the insides of the graphite, and am
relatively new to gcc's insides, so I could be wrong; also the script
relies on the pass flags, and they're not necessarily correct either...
Hope this is helpful
Dave
next prev parent reply other threads:[~2012-02-17 19:35 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-17 9:53 Arnaldo
2012-02-17 22:52 ` David Malcolm [this message]
2012-02-18 10:37 ` Tobias Grosser
2012-02-18 22:54 ` Arnaldo
2012-03-05 13:51 ` Arnaldo
2012-03-05 13:58 ` Richard Guenther
2012-03-05 14:00 ` Michael Matz
2012-03-05 14:52 ` Arnaldo
2012-03-05 14:58 ` Richard Guenther
2012-03-05 15:24 ` David Edelsohn
2012-03-05 15:31 ` Arnaldo
2012-03-05 15:37 ` Richard Guenther
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=1329507251.15787.25.camel@surprise \
--to=dmalcolm@redhat.com \
--cc=arnaldo.cruz@upr.edu \
--cc=gcc@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).