From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-patches-return-408260-listarch-gcc-patches=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 111475 invoked by alias); 24 Sep 2015 16:39:05 -0000
Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-patches.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-patches/>
List-Post: <mailto:gcc-patches@gcc.gnu.org>
List-Help: <mailto:gcc-patches-help@gcc.gnu.org>
Sender: gcc-patches-owner@gcc.gnu.org
Received: (qmail 111377 invoked by uid 89); 24 Sep 2015 16:39:04 -0000
Authentication-Results: sourceware.org; auth=none
X-Virus-Found: No
X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL,BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.3.2
X-HELO: gate.crashing.org
Received: from gate.crashing.org (HELO gate.crashing.org) (63.228.1.57) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-SHA encrypted) ESMTPS; Thu, 24 Sep 2015 16:39:03 +0000
Received: from gate.crashing.org (localhost.localdomain [127.0.0.1])	by gate.crashing.org (8.14.1/8.13.8) with ESMTP id t8OGcxol003746;	Thu, 24 Sep 2015 11:38:59 -0500
Received: (from segher@localhost)	by gate.crashing.org (8.14.1/8.14.1/Submit) id t8OGcwPl003745;	Thu, 24 Sep 2015 11:38:58 -0500
Date: Thu, 24 Sep 2015 17:22:00 -0000
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Steven Bosscher <stevenb.gcc@gmail.com>
Cc: GCC Patches <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH 2/4] bb-reorder: Add the "simple" algorithm
Message-ID: <20150924163858.GA3427@gate.crashing.org>
References: <cover.1443028412.git.segher@kernel.crashing.org> <a691f5437e32cec13ab9f9776975e95be67c4811.1443028412.git.segher@kernel.crashing.org> <CABu31nP3JJB8wXpTAbUJyzc23O4x+NcjW6tCE9S0qJ1e7tJRZQ@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CABu31nP3JJB8wXpTAbUJyzc23O4x+NcjW6tCE9S0qJ1e7tJRZQ@mail.gmail.com>
User-Agent: Mutt/1.4.2.3i
X-IsSubscribed: yes
X-SW-Source: 2015-09/txt/msg01885.txt.bz2

On Thu, Sep 24, 2015 at 06:03:33PM +0200, Steven Bosscher wrote:
> On Thu, Sep 24, 2015 at 12:06 AM, Segher Boessenkool wrote:
> > +  /* First, collect all edges that can be optimized by reordering blocks:
> > +     simple jumps and conditional jumps, as well as the function entry edge.  */
> > +
> > +  int n = 0;
> > +  edges[n++] = EDGE_SUCC (ENTRY_BLOCK_PTR_FOR_FN (cfun), 0);
> > +
> > +  basic_block bb;
> > +  FOR_EACH_BB_FN (bb, cfun)
> > +    {
> > +      rtx_insn *end = BB_END (bb);
> > +
> > +      if (computed_jump_p (end) || tablejump_p (end, NULL, NULL))
> > +       continue;
> 
> Should handle ASM jumps.

Right, those are considered as optimisable now, although they are not.
Will fix.

> > +  FOR_ALL_BB_FN (bb, cfun)
> > +    bb->aux = bb;
> 
> Bit tricky for the ENTRY and EXIT blocks, that are not really basic
> blocks. After the pass, EXIT should not end up pointing to itself.

But it doesn't, the next line already takes care of it.


Segher