From: Richard Guenther <rguenther@suse.de>
To: Sebastian Pop <sebpop@gmail.com>
Cc: GCC Patches <gcc-patches@gcc.gnu.org>
Subject: Re: [patch] Fix PR44483: incrementally gimplify BB predicates to avoid redundant computations.
Date: Fri, 11 Jun 2010 09:32:00 -0000 [thread overview]
Message-ID: <alpine.LNX.2.00.1006111105470.1429@zhemvz.fhfr.qr> (raw)
In-Reply-To: <AANLkTinGpk3FyNKkdiLn7hh2Ovp3_JuzRVevvOGm_L5h@mail.gmail.com>
On Thu, 10 Jun 2010, Sebastian Pop wrote:
> Hi,
>
> The attached patch fixes PR44483 by early gimplifying the expressions
> that are used in the predicates of basic blocks: in the testcase,
> these expressions are redundant and if not gimplified in time, they
> end up to form an exponential tree of conditions.
>
> With this patch we gimplify the predicates, and collect the gimple
> sequences during the analysis phase. Because we now force the
> predicate of a BB to be an SSA_NAME, this is what is used further on
> for the next basic block, avoiding the full expression to be
> recomputed. When the if-conversion analysis fails, the SSA_NAMEs used
> in the gimple sequences are released using free_stmt_operands.
> Otherwise the gimple sequences are inserted in the end of each basic
> block that is predicated by these computations. These computations
> are then used in the if-conversion of the PHI nodes following the BB.
>
> The patch passed make -k check RUNTESTFLAGS=tree-ssa.exp and vect.exp
> and is right now under regstrap on amd64-linux. Ok for trunk after regstrap?
Ok.
Thanks,
Richard.
next prev parent reply other threads:[~2010-06-11 9:06 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-06-10 23:45 Sebastian Pop
2010-06-11 9:32 ` Richard Guenther [this message]
2010-06-11 19:21 ` Sebastian Pop
2010-06-29 9:46 ` Ira Rosen
2010-06-29 10:27 ` 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=alpine.LNX.2.00.1006111105470.1429@zhemvz.fhfr.qr \
--to=rguenther@suse.de \
--cc=gcc-patches@gcc.gnu.org \
--cc=sebpop@gmail.com \
/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).